TW202420434A - Aging condition evaluation device and setting method - Google Patents

Abstract

本發明提供一種老化條件評估裝置，其係評估製程裝置的老化處理的設定條件亦即老化條件的老化條件評估裝置，其係具備：試料台，其係支持在前述製程裝置被處理的試料；照明光學系統，其係對載置於前述試料台的試料照射照明光；複數檢測光學系統，其係將來自前述試料的光聚光而轉換為電訊號且輸出檢測訊號；及訊號處理裝置，其係處理前述複數檢測光學系統的檢測訊號，前述訊號處理裝置係掃描在前述製程裝置中伴隨老化處理所處理的1批次的試料之中初期被處理的初期試料來抽出前述初期試料的霧度訊號，藉由將前述初期試料的前述霧度訊號與基準霧度訊號作比較時的差，來判定老化條件的適當與否。The present invention provides an aging condition evaluation device, which is an aging condition evaluation device for evaluating the setting conditions of the aging treatment of a process device, that is, the aging condition, and is equipped with: a sample stage, which supports the sample to be processed in the aforementioned process device; an illumination optical system, which irradiates the sample placed on the aforementioned sample stage with illumination light; a plurality of detection optical systems, which focus the light from the aforementioned sample and convert it into an electrical signal and output the detection signal; A detection signal; and a signal processing device, which processes the detection signals of the aforementioned multiple detection optical systems, wherein the aforementioned signal processing device scans an initial sample that is initially processed among a batch of samples that are processed with an aging treatment in the aforementioned process device to extract a haze signal of the aforementioned initial sample, and determines whether the aging conditions are appropriate by comparing the aforementioned haze signal of the aforementioned initial sample with a reference haze signal.

Description

老化條件的評估裝置及設定方法Aging condition evaluation device and setting method

本發明係關於評估例如半導體製造工程所使用的電漿蝕刻裝置等製程裝置的老化條件的老化條件評估裝置及老化條件設定方法。The present invention relates to an aging condition evaluation device and an aging condition setting method for evaluating the aging conditions of a process device such as a plasma etching device used in a semiconductor manufacturing process.

在處理半導體晶圓的製程裝置中，有例如安置收納有N片(複數片)晶圓的殼體，且殼體內的N片晶圓作為1批次被處理的情形。例如在電漿蝕刻裝置中，將晶圓安置(set)在腔室內，供給預定的氣體來進行放電，藉此將氣體電漿化，以所生成的電漿將晶圓進行蝕刻處理(專利文獻1等)。 [先前技術文獻] [專利文獻] In a process device for processing semiconductor wafers, for example, a housing containing N (plural) wafers is placed, and the N wafers in the housing are processed as one batch. For example, in a plasma etching device, the wafer is placed (set) in a chamber, and a predetermined gas is supplied to discharge, thereby plasmatizing the gas, and etching the wafer with the generated plasma (Patent Document 1, etc.). [Prior Technical Document] [Patent Document]

[專利文獻1]日本特開2011-100865號公報[Patent Document 1] Japanese Patent Application Publication No. 2011-100865

(發明所欲解決之問題)(Invent the problem you want to solve)

例如在電漿蝕刻裝置中，為了實施安定的處理，較宜為在處理晶圓時，腔室處於預定的狀況(condition)。但是，晶圓的批次被供給至電漿蝕刻裝置的間隔各式各樣，並非為一定，若等待接下來的批次的到達的待機時間變長，腔室的溫度會降低。假設在腔室冷卻的狀態下處理之後到達的批次，第N片晶圓處理時，腔室的狀況可整頓，但是最初的幾片，尤其第1片晶圓係在腔室的狀況未整頓之前被處理。如上所示之狀況不均係即使腔室內的氣體充滿度不同亦可能發生。如該電漿蝕刻裝置之例所示，在製程裝置中，在批次的第1片與第N片晶圓處理時的腔室的狀況可能產生差異。此時，在第1片與第N片晶圓的處理結果產生差異，若差異甚大，有第1片或最初的幾片晶圓成為不良的情形。For example, in a plasma etching device, in order to implement stable processing, it is preferable that the chamber is in a predetermined condition when processing wafers. However, the intervals at which batches of wafers are supplied to the plasma etching device vary and are not constant. If the waiting time for the next batch to arrive becomes longer, the temperature of the chamber will decrease. Assuming that the batch that arrives later is processed in a cooled state of the chamber, the condition of the chamber can be rectified when the Nth wafer is processed, but the first few wafers, especially the first wafer, are processed before the condition of the chamber is rectified. The uneven condition shown above may occur even if the gas fullness in the chamber is different. As shown in the example of the plasma etching device, in the process device, the chamber conditions may differ when processing the first and Nth wafers of a batch. In this case, the processing results of the first and Nth wafers differ, and if the difference is large, the first or first few wafers may become defective.

因此，一般而言，在製程裝置中係視需要執行處理批次的第1片晶圓之前整頓腔室的狀況的處理(在本案說明書中記載為老化處理)。例如在電漿蝕刻裝置中，一邊對腔室供給預定的氣體一邊執行“校正放電”，藉此嘗試抑制第1片晶圓與第N片晶圓處理時的電漿發光狀態的差。Therefore, generally speaking, in a process device, a process is performed as needed to adjust the state of the chamber before processing the first wafer of a batch (described as an aging process in the specification of this case). For example, in a plasma etching device, a "calibration discharge" is performed while supplying a predetermined gas to the chamber, thereby attempting to suppress the difference in plasma luminescence state when processing the first wafer and the Nth wafer.

但是，在製程裝置中適用於晶圓處理的製程條件係按每個工程，甚至按每個晶圓的種類(按每個晶圓的製造階段、或再生晶圓、新品晶圓等晶圓的種類)在製程裝置製造商或使用者的製程部門中作初期設定。例如藉由調整電漿蝕刻裝置的微波輸出或電漿放電時間、氣體流量等參數來進行設定。在製程裝置中係除了製程條件之外，亦設定前述之在待機時間進行校正放電的老化處理的條件(以下為老化條件)。老化條件係必須按每個製程條件進行設定。將製程條件的一部分參數，調整為校正放電用來進行設定。此外，用以將製程裝置的狀況整頓為必要且充分的程度的老化條件係即使對應的製程條件相同，亦依之前所述的待機時間而異。如上所示，與製程條件同樣地，老化條件亦按照工程或晶圓的種類由涉及多方面的參數作選擇/調整，因此需要極大的勞力及時間。However, the process conditions applied to wafer processing in the process equipment are initially set in the process department of the process equipment manufacturer or user for each process or even for each type of wafer (according to the manufacturing stage of each wafer, or the type of wafer such as recycled wafer, new wafer, etc.). For example, the setting is performed by adjusting the microwave output of the plasma etching device or the plasma discharge time, gas flow rate and other parameters. In addition to the process conditions, the process equipment also sets the aforementioned aging treatment conditions for correcting the discharge during the standby time (hereinafter referred to as aging conditions). The aging conditions must be set for each process condition. Some parameters of the process conditions are adjusted for the correction discharge for setting. In addition, the aging conditions used to adjust the conditions of the process equipment to the necessary and sufficient level vary according to the standby time described above, even if the corresponding process conditions are the same. As shown above, like the process conditions, the aging conditions are also selected/adjusted based on various parameters according to the type of process or wafer, so it requires a lot of effort and time.

老化條件係藉由比較例如同一批次的第1片與第N片晶圓的結果來評估好壞。在該晶圓的完成結果的比較檢查中，係有使用例如OCD(Optical Critical Dimension，光學臨界尺度)的情形。在使用OCD的檢查中，由於檢查對象為CD(Critical Dimension，臨界尺度)，因此無法藉由未形成有圖案的晶圓來評估老化條件。因此，例如若在半導體的研究開發階段準備晶圓供老化條件的評估用，係必須製造附圖案晶圓，耗費成本。此外，CD值的測定若為使用電子線的CD-SEM的情形，僅針對晶圓內一小部分，若為OCD的情形，亦僅針對晶圓表面的幾十程度的測定部位來進行，藉此無法沒有遺漏地確認晶圓全面的處理狀態，亦有無法藉由檢查部位的選擇來感測老化條件的不完備的情形。The aging condition is evaluated by comparing the results of the first and Nth wafers in the same batch. In the comparative inspection of the finished results of the wafer, for example, OCD (Optical Critical Dimension) is used. In the inspection using OCD, since the inspection object is CD (Critical Dimension), the aging condition cannot be evaluated by a wafer without a pattern. Therefore, if a wafer is prepared for the evaluation of aging conditions in the research and development stage of semiconductors, it is necessary to manufacture a wafer with a pattern, which is costly. In addition, when CD values are measured using CD-SEM using electron beams, they are only measured on a small part of the wafer, and when OCD is used, they are only measured on a few dozen areas on the wafer surface. This makes it impossible to fully confirm the overall processing status of the wafer, and it is also impossible to detect the incompleteness of aging conditions by selecting the inspection area.

本發明之目的在提供可在短時間精度佳地評估適用於製程裝置的老化條件的老化條件的評估裝置及設定方法。 (解決問題之技術手段) The purpose of the present invention is to provide an evaluation device and a setting method for aging conditions that can evaluate aging conditions applicable to process equipment with high accuracy in a short time. (Technical means for solving the problem)

為達成上述目的，本發明係提供一種老化條件評估裝置，其係評估製程裝置的老化處理的設定條件亦即老化條件的老化條件評估裝置，其係具備：試料台，其係支持在前述製程裝置被處理的試料；照明光學系統，其係對載置於前述試料台的試料照射照明光；複數檢測光學系統，其係將來自前述試料的光聚光而轉換為電訊號且輸出檢測訊號；及訊號處理裝置，其係處理前述複數檢測光學系統的檢測訊號，前述訊號處理裝置係掃描在前述製程裝置中伴隨老化處理所處理的1批次的試料之中初期被處理的初期試料來抽出前述初期試料的霧度訊號，藉由將前述初期試料的前述霧度訊號與基準霧度訊號作比較時的差，來判定老化條件的適當與否。 (發明效果) To achieve the above-mentioned purpose, the present invention provides an aging condition evaluation device, which is an aging condition evaluation device for evaluating the setting conditions of the aging treatment of a process device, that is, the aging condition, and is equipped with: a sample table, which supports the sample to be processed in the aforementioned process device; an illumination optical system, which irradiates the sample placed on the aforementioned sample table with illumination light; and a plurality of detection optical systems, which focus the light from the aforementioned sample and convert it into an electrical signal. and outputs a detection signal; and a signal processing device, which processes the detection signals of the aforementioned multiple detection optical systems, the aforementioned signal processing device scans the initial sample that is initially processed among a batch of samples that are processed in the aforementioned process device along with the aging treatment to extract the haze signal of the aforementioned initial sample, and determines whether the aging conditions are appropriate or not by comparing the difference between the aforementioned haze signal of the aforementioned initial sample and the reference haze signal. (Effect of the invention)

藉由本發明，可在短時間精度佳地評估適用於製程裝置的老化條件。By means of the present invention, the aging conditions applicable to the process equipment can be evaluated with high accuracy in a short time.

以下使用圖面，說明本發明之實施例。 以下各實施例中所說明的老化條件評估裝置(以下適當簡記為評估裝置)係在半導體製造製程的過程中掃描試料，在此為晶圓(裸晶圓、附膜晶圓、附圖案晶圓等)，由該晶圓狀態來評估老化條件。以該評估裝置之一例而言，使用檢查試料的缺陷的光學缺陷檢查裝置。光學缺陷檢查裝置係以根據掃描試料而得的反射光或散射光的訊號，輸出通常附著或形成在晶圓的缺陷的數量或座標、種類等。與將電子線或X線等作為光源的診斷裝置相比，光學缺陷檢查裝置係掃描速度非常快。因此，在將電子線或X線等作為能量源的診斷裝置中，由於時間制約，僅可測定試料的極數點，在光學缺陷檢查裝置，尤其使用散射光的暗視野式檢查裝置中係可掃描試料全面且由試料全面的狀態來評估老化條件。在該光學缺陷檢查裝置中根據掃描試料而得的光的訊號係不僅被使用在供缺陷檢測用的缺陷訊號，有被稱為霧度訊號的訊號。若將變動頻率(訊號強度的時間變動)比預定值高的訊號設為高頻、比預定值低的訊號設為低頻時，缺陷訊號係在根據由試料所得的光的訊號之中相當於高頻成分。相反地，霧度訊號係相當於低頻成分。例如異物般，起因於附著在試料之相對較大的凹凸的訊號係容易被檢測為高頻成分，起因於試料上的膜的厚度、或試料表面的極微小凹凸(粗糙度(roughness))等晶圓本身的特性的訊號容易被檢測為低頻成分。 The following uses drawings to illustrate embodiments of the present invention. The aging condition evaluation device (hereinafter referred to as the evaluation device) described in the following embodiments scans a sample, in this case a wafer (bare wafer, film-attached wafer, patterned wafer, etc.) during the semiconductor manufacturing process, and evaluates the aging condition based on the state of the wafer. As an example of the evaluation device, an optical defect inspection device for inspecting defects in the sample is used. The optical defect inspection device outputs the number, coordinates, type, etc. of defects usually attached to or formed on the wafer based on the signal of reflected light or scattered light obtained by scanning the sample. Compared with diagnostic devices that use electron beams or X-rays as light sources, the optical defect inspection device has a very fast scanning speed. Therefore, in diagnostic devices that use electron beams or X-rays as energy sources, only the extreme points of the sample can be measured due to time constraints. In optical defect inspection devices, especially dark field inspection devices that use scattered light, the entire sample can be scanned and the aging condition can be evaluated based on the state of the entire sample. In this optical defect inspection device, the light signal obtained by scanning the sample is not only used as a defect signal for defect detection, but also a signal called a haze signal. If the signal with a variation frequency (temporal variation of signal intensity) higher than a predetermined value is set to a high frequency, and the signal lower than the predetermined value is set to a low frequency, the defect signal is equivalent to a high-frequency component in the light signal obtained from the sample. Conversely, the haze signal is equivalent to a low-frequency component. For example, signals caused by relatively large bumps and depressions attached to the sample, such as foreign matter, are easily detected as high-frequency components, while signals caused by the characteristics of the wafer itself, such as the thickness of the film on the sample or the extremely small bumps and depressions (roughness) on the sample surface, are easily detected as low-frequency components.

各實施例的評估裝置係具有根據將在製程裝置中伴隨老化處理所處理的試料全面掃描而得的霧度訊號，評估適用於處理所檢查的試料的製程裝置的老化處理的條件(老化條件)的特異的功能。評估裝置係活用在試料的缺陷檢查中一般未被使用(被去除)的霧度訊號，根據針對試料所得的霧度訊號，評估處理了該試料的製程裝置的老化條件。The evaluation device of each embodiment has a unique function of evaluating the conditions (aging conditions) of the aging treatment applied to the process device that processes the sample to be inspected based on the haze signal obtained by scanning the sample in the process device along with the aging treatment. The evaluation device utilizes the haze signal that is generally not used (removed) in the defect inspection of the sample, and evaluates the aging conditions of the process device that processes the sample based on the haze signal obtained for the sample.

在評估裝置中，考慮針對伴隨老化處理而在製程裝置被處理的1批次(N片)的試料，取得霧度訊號的情形。「伴隨老化處理」意指在老化處理後，未夾著其他批次的處理而接連老化處理進行該批次的處理。N為2以上的自然數，以一例而言，為25左右。此時，若在第1片試料與最後的第N片試料，在霧度訊號的值或分布產生差異，推定製程裝置中的腔室的狀況在第1片與第N片為不同。更言之，若製程裝置中的老化條件欠缺妥當性，在伴隨老化處理所進行的批次的處理中，可在製程裝置的狀況(腔室的溫度或氣體的充滿度等)未整頓之前處理第1片。在該情形下，亦在第1片處理時，腔室雖未形成為所希望的狀況，但是處理接續如第2片、第3片之前，腔室係成為所希望的狀況。但是，結果批次的大部分試料係被良好處理，但是最初的1、2片試料係有處理不充分的情形。若處理狀態低於容許水準，該試料會成為不良。如此之製程裝置中的腔室的狀況的差若為處理後的試料的結果，例如若為在電漿蝕刻裝置所處理的試料，若該差明顯，即出現在試料的CD值、表面粗糙度或表面膜厚。但是，計測CD值、表面粗糙度或表面膜厚的裝置，以使用者的運用而言，尤其在掃描速度慢的測定裝置中基於測定成本的關係，大多為以取樣來測定1批次內的1~數片，未測定多數晶圓而轉至接下來的製程的情形。此外，因不適當的老化條件所致之對處理試料的影響亦有形成為未被捕捉為CD值、表面粗糙度或表面膜厚的微小、複合或別的狀態差所表示的情形。此時，在製程裝置處理之後，無法確認老化條件的好壞。在各實施例的評估裝置中，活用可高速全面掃描的優點，根據霧度訊號，評估出現在試料的老化條件的好壞。In the evaluation device, consider the case where a mist signal is obtained for a batch (N pieces) of samples that are processed in a process device following an aging treatment. "Accompanying the aging treatment" means that the aging treatment is performed on the batch without intervening other batches after the aging treatment. N is a natural number greater than 2, and is approximately 25 as an example. At this time, if there is a difference in the value or distribution of the mist signal between the first sample and the last N-th sample, it is estimated that the condition of the chamber in the process device is different between the first sample and the N-th sample. In other words, if the aging conditions in the process device are not appropriate, in the processing of the batch following the aging treatment, the first piece may be processed before the condition of the process device (such as the temperature of the chamber or the fullness of the gas) is rectified. In this case, although the chamber was not in the desired state when the first piece was processed, the chamber was in the desired state before the second and third pieces were processed. However, most of the samples in the batch were processed well, but the first 1 or 2 samples were not processed sufficiently. If the processing state is lower than the allowable level, the sample will become defective. If the difference in the state of the chamber in such a process device is the result of the sample after processing, for example, if it is a sample processed in a plasma etching device, if the difference is obvious, it will appear in the CD value, surface roughness or surface film thickness of the sample. However, in terms of user operation, especially in measuring devices with slow scanning speeds, most users measure 1 to 2 wafers in a batch by sampling, and do not measure the majority of wafers before moving on to the next process due to the measurement cost. In addition, the impact of inappropriate aging conditions on the processed samples may not be captured as a small, complex or other state difference in CD value, surface roughness or surface film thickness. In this case, the quality of the aging conditions cannot be confirmed after the process device is processed. In the evaluation device of each embodiment, the advantage of high-speed full scanning is utilized to evaluate the quality of the aging conditions appearing in the sample based on the haze signal.

其中，形成為所希望的狀況的是從第1片、或從第2片、第3片或第5片，係取決於所設定的老化條件。因此，附記將在因不適當的老化條件而未形成為所希望的狀況的腔室被處理的1批次的最初1或數片設為「初期晶圓」，實際上並非僅限於第1、2片。Among them, whether the desired state is formed from the first wafer, the second wafer, the third wafer, or the fifth wafer depends on the set aging conditions. Therefore, the first one or more wafers of a batch processed in a chamber that did not form the desired state due to inappropriate aging conditions are referred to as "initial wafers", but in fact, they are not limited to the first and second wafers.

以下說明評估裝置的具體例。A specific example of the evaluation device is described below.

(第1實施例) -老化條件評估裝置- 圖1係本發明之第1實施例之老化條件評估裝置之一構成例的模式圖。將Z軸朝鉛直方向延伸的XYZ正交座標系定義如圖1所示。評估裝置100係將試料W作為檢查對象，且檢測該試料W的表面的異物的附著或成膜異常等缺陷。評估裝置100係一邊使試料W朝周方向(θ方向)旋轉一邊朝徑方向(r方向)移動來作掃描的旋轉掃描方式的裝置。 (First embodiment) -Aging condition evaluation device- Figure 1 is a schematic diagram of one configuration example of the aging condition evaluation device of the first embodiment of the present invention. The XYZ orthogonal coordinate system extending the Z axis in the vertical direction is defined as shown in Figure 1. The evaluation device 100 takes the sample W as the inspection object and detects defects such as adhesion of foreign matter or film formation abnormality on the surface of the sample W. The evaluation device 100 is a rotation scanning device that scans the sample W while rotating it in the circumferential direction (θ direction) and moving it in the radial direction (r direction).

評估裝置100係包含有：載台ST、照明光學系統A、複數檢測光學系統Bn(n=1,2…)、感測器Cn、Cn’(n=1,2…)、訊號處理裝置D、記憶裝置DB、控制裝置E1、輸入裝置E2、監視器E3。The evaluation device 100 includes: a carrier ST, an illumination optical system A, a plurality of detection optical systems Bn (n=1, 2...), sensors Cn, Cn' (n=1, 2...), a signal processing device D, a memory device DB, a control device E1, an input device E2, and a monitor E3.

-載台- 載台ST係包含試料台ST1及掃描裝置ST2所構成的裝置。試料台ST1係支持在電漿蝕刻裝置等製程裝置中所處理的試料W的台。掃描裝置ST2係驅動試料台ST1而使試料W與照明光學系統A的相對位置發生變化的裝置，雖省略詳細圖示，構成為包含平移載台、旋轉載台、及Z載台。旋轉載台透過Z載台而被裝載在平移載台，試料台ST1被支持在旋轉載台。平移載台係連同旋轉載台一起朝水平方向平移移動。旋轉載台係將朝上下延伸的旋轉軸作為中心而作旋轉(自轉)。Z載台係發揮調整試料W的表面的高度的功能。 -Stage- Stage ST is a device composed of a sample stage ST1 and a scanning device ST2. Sample stage ST1 is a stage that supports sample W processed in a process device such as a plasma etching device. Scanning device ST2 is a device that drives sample stage ST1 to change the relative position of sample W and illumination optical system A. Although detailed illustrations are omitted, it is composed of a translation stage, a rotation stage, and a Z stage. The rotation stage is mounted on the translation stage through the Z stage, and sample stage ST1 is supported on the rotation stage. The translation stage translates horizontally together with the rotation stage. The rotation stage rotates (rotates) around a rotation axis extending upward and downward. The Z stage has the function of adjusting the height of the surface of sample W.

圖2係表示藉由掃描裝置ST2所得之試料W的掃描軌道的模式圖。容後敘述，由照明光學系統A被出射的照明光對試料W的表面的入射區域亦即射束點BS係如該圖所示具有朝一方向為較長的照明強度分布的微小的點。將射束點BS的長軸方向設為s2、與長軸相交的方向(例如與長軸呈正交的短軸方向)設為s1。試料W伴隨旋轉載台的旋轉作旋轉，射束點BS相對試料W的表面朝s1方向掃描，伴隨平移載台的平移，試料W朝水平方向移動，射束點BS相對試料W的表面朝s2方向掃描。射束點BS係在試料W作1旋轉的期間，以射束點BS的s2方向的長度以下的距離朝s2方向移動。藉由如上所示之掃描裝置ST2的動作，試料W一邊旋轉一邊平移，藉此，如圖2所示，射束點BS由試料W的中心至外緣或其附近描繪螺旋狀的軌跡進行移動，且掃描試料W的表面的全體。FIG. 2 is a schematic diagram showing the scanning trajectory of the sample W obtained by the scanning device ST2. As will be described later, the incident area of the illumination light emitted from the illumination optical system A on the surface of the sample W, that is, the beam spot BS, is a tiny spot having an illumination intensity distribution that is relatively long in one direction as shown in the figure. The long axis direction of the beam spot BS is set as s2, and the direction intersecting the long axis (for example, the short axis direction that is orthogonal to the long axis) is set as s1. The sample W rotates with the rotation of the rotating stage, and the beam spot BS scans the surface of the sample W in the s1 direction. With the translation of the translation stage, the sample W moves in the horizontal direction, and the beam spot BS scans the surface of the sample W in the s2 direction. The beam spot BS moves in the s2 direction by a distance less than the length of the beam spot BS in the s2 direction during one rotation of the sample W. By the operation of the scanning device ST2 as described above, the sample W is rotated and translated, thereby, as shown in FIG. 2 , the beam spot BS moves along a spiral trajectory from the center of the sample W to the outer edge or its vicinity, and scans the entire surface of the sample W.

其中，載台ST亦可採用取代旋轉載台(或除此之外)，具備朝與平移載台的移動軸在水平面內相交的方向將移動軸延長的另1個平移載台的構成。此時，如圖3所示，射束點BS並非為螺旋軌道，而是在直線軌道折返掃描試料W的表面。在同圖之例中，將第1平移載台朝s1方向以定速進行平移驅動，將第2平移載台以預定距離(例如射束點BS的s2方向的長度以下的距離)朝s2方向進行驅動之後，再次將第1平移載台朝s1方向折返進行平移驅動。藉此反覆射束點BS朝s1方向的直線掃描與朝s2方向的移動，掃描試料W的全表面。與該XY掃描方式相比，圖2的旋轉掃描方式係未伴隨反覆加減速的往返動作，因此可短縮試料W的檢查時間。The stage ST may be replaced with (or in addition to) the rotating stage and may have another translation stage whose moving axis is extended in a direction intersecting with the moving axis of the translation stage in a horizontal plane. In this case, as shown in FIG3 , the beam spot BS does not follow a spiral track but scans the surface of the sample W by turning back on a straight track. In the example of the same figure, the first translation stage is translationally driven in the s1 direction at a constant speed, the second translation stage is driven in the s2 direction at a predetermined distance (e.g., a distance less than the length of the beam spot BS in the s2 direction), and then the first translation stage is turned back and translationally driven in the s1 direction again. In this way, the entire surface of the sample W is scanned by repeating the straight line scanning of the beam spot BS in the s1 direction and the movement in the s2 direction. Compared with the XY scanning method, the rotation scanning method of FIG. 2 is not accompanied by a reciprocating motion of repeated acceleration and deceleration, so the inspection time of the sample W can be shortened.

-照明光學系統- 圖1所示之照明光學系統A係構成為包含光學元件群，俾以對載置於試料台ST1的試料W照射所希望的照明光。如圖1所示，該照明光學系統A係具備有：雷射光源A1、衰減器A2、出射光調整單元A3、擴束器A4、偏光控制單元A5、聚光光學單元A6、反射鏡A7-A9等。 -Illumination optical system- The illumination optical system A shown in FIG1 is configured to include an optical element group so as to irradiate the desired illumination light to the sample W placed on the sample stage ST1. As shown in FIG1, the illumination optical system A includes: a laser light source A1, an attenuator A2, an output light adjustment unit A3, a beam expander A4, a polarization control unit A5, a focusing optical unit A6, and reflectors A7-A9, etc.

・雷射光源 雷射光源A1係出射雷射射束作為照明光的單元。若在評估裝置100檢測試料W的表面近旁的微小缺陷，使用以不易浸透至試料W的內部的短波長(波長355nm以下)的紫外或真空紫外將輸出2W以上的高輸出的雷射射束進行振盪者作為雷射光源A1。若在評估裝置100檢測試料W的內部的缺陷，使用將波長長且容易浸透至試料W的內部的可見或紅外的雷射射束進行振盪者作為雷射光源A1。 ・Laser light source The laser light source A1 is a unit that emits a laser beam as illumination light. When the evaluation device 100 detects minute defects near the surface of the sample W, a laser light source A1 that oscillates a high-output laser beam of 2W or more with short-wavelength (wavelength below 355nm) ultraviolet or vacuum ultraviolet light that does not easily penetrate into the inside of the sample W is used. When the evaluation device 100 detects defects inside the sample W, a laser light source A1 that oscillates a visible or infrared laser beam with a long wavelength that easily penetrates into the inside of the sample W is used.

・衰減器 圖4係將衰減器A2抽出表示的模式圖。衰減器A2係使來自雷射光源A1的照明光的光強度衰減的單元，在本實施例中係例示將第1偏光板A2a、1/2波長板A2b、第2偏光板A2c加以組合的構成。1/2波長板A2b係構成為可繞照明光的光軸旋轉。入射至衰減器A2的照明光係在以第1偏光板A2a轉換為直線偏光之後，偏光方向被調整為1/2波長板A2b的慢軸方位角而通過第2偏光板A2c。藉由1/2波長板A2b的方位角調整，照明光的光強度以任意比率作衰減。若入射至衰減器A2的照明光的直線偏光度十分高，第1偏光板A2a係可省略。在衰減器A2係使用所入射的照明光與減光率的關係被事前校準者。其中，衰減器A2並非限定於圖4所例示的構成，亦可使用具有梯度濃度分布的ND濾波器所構成，可形成為可藉由濃度不同的複數ND濾波器的組合來調整衰減效果的構成。 ・Attenuator FIG4 is a schematic diagram showing an extracted attenuator A2. The attenuator A2 is a unit that attenuates the light intensity of the illumination light from the laser light source A1. In this embodiment, the attenuator A2 is a structure in which the first polarizer A2a, the 1/2 wavelength plate A2b, and the second polarizer A2c are combined. The 1/2 wavelength plate A2b is configured to be rotatable around the optical axis of the illumination light. The illumination light incident on the attenuator A2 is converted into linear polarization by the first polarizer A2a, and then the polarization direction is adjusted to the slow axis azimuth of the 1/2 wavelength plate A2b and passes through the second polarizer A2c. By adjusting the azimuth of the 1/2 wavelength plate A2b, the light intensity of the illumination light is attenuated at an arbitrary ratio. If the linear polarization degree of the illumination light incident on the attenuator A2 is very high, the first polarizer A2a can be omitted. The attenuator A2 is calibrated in advance using the relationship between the incident illumination light and the attenuation rate. The attenuator A2 is not limited to the structure shown in FIG. 4, but can also be composed of an ND filter with a gradient concentration distribution, and can be formed into a structure that can adjust the attenuation effect by combining multiple ND filters with different concentrations.

・出射光調整單元 圖1所示之出射光調整單元A3係調整在衰減器A2作衰減的照明光的光軸的角度的單元，在本實施例中係構成為包含複數反射鏡A3a、A3b。為在反射鏡A3a、A3b依序反射照明光的構成，在本實施例中係構成為對反射鏡A3a的照明光的入射/出射面與對反射鏡A3b的照明光的入射/出射面呈正交。入射/出射面係指包含入射至反射鏡的光的光軸、及由反射鏡被出射的光的光軸的面。若形成為照明光朝+X方向入射至反射鏡A3a的構成，與模式圖1不同，惟例如照明光係在反射鏡A3a朝+Y方向，之後在反射鏡A3b朝+Z方向改變行進方向。為將對反射鏡A3a的照明光的入射/出射面設為XY平面、對反射鏡A3b的入射/出射面設為YZ平面之例。接著，在反射鏡A3a、A3b係配備有使反射鏡A3a、A3b分別作平移移動的機構(未圖示)及作傾斜(tilt)的機構(未圖示)。反射鏡A3a、A3b係例如朝對自己的照明光的入射方向或出射方向作平行移動，此外在與入射/出射面的法線周圍呈傾斜。藉此，針對例如由出射光調整單元A3朝+Z方向出射的照明光的光軸，可獨立調整XZ平面內的偏移量及角度、與YZ面內的偏移(offset)量及角度。在本實施例中係例示使用了2片反射鏡A3a、A3b的構成，惟亦可形成為使用了3片以上的反射鏡的構成。 ・Outgoing light adjustment unit The outgoing light adjustment unit A3 shown in FIG1 is a unit for adjusting the angle of the optical axis of the illumination light attenuated by the attenuator A2, and in this embodiment, it is configured to include a plurality of reflectors A3a and A3b. It is a configuration in which the illumination light is sequentially reflected by the reflectors A3a and A3b, and in this embodiment, it is configured so that the incident/exit surface of the illumination light for the reflector A3a is orthogonal to the incident/exit surface of the illumination light for the reflector A3b. The incident/exit surface refers to a surface including the optical axis of the light incident on the reflector and the optical axis of the light emitted by the reflector. If the structure is formed so that the illumination light is incident on the reflector A3a in the +X direction, it is different from the model figure 1, but for example, the illumination light changes its direction in the +Y direction at the reflector A3a, and then changes its direction in the +Z direction at the reflector A3b. This is an example in which the incident/exit surface of the illumination light for the reflector A3a is set to the XY plane, and the incident/exit surface of the reflector A3b is set to the YZ plane. Then, the reflectors A3a and A3b are equipped with a mechanism (not shown) for making the reflectors A3a and A3b translate and tilt respectively. The reflectors A3a and A3b move parallel to the incident direction or the exit direction of the illumination light for themselves, for example, and are also tilted around the normal to the incident/exit surface. Thus, for example, the optical axis of the illumination light emitted from the emission light adjustment unit A3 in the +Z direction can be independently adjusted in the XZ plane and the offset (offset) and angle in the YZ plane. In this embodiment, a configuration using two reflectors A3a and A3b is illustrated, but a configuration using more than three reflectors can also be used.

・擴束器 擴束器A4係將所入射的照明光的光束直徑放大的單元，具有複數透鏡A4a、A4b。列舉使用凹透鏡作為透鏡A4a且使用凸透鏡作為透鏡A4b的伽利略型作為擴束器A4之一例。在擴束器A4係配備有透鏡A4a、A4b的間隔調整機構(變焦機構)，光束直徑的放大率藉由調整透鏡A4a、A4b的間隔而改變。若入射至擴束器A4的照明光非為平行光束，亦可藉由透鏡A4a、A4b的間隔調整，與光束直徑一併進行準直(光束的準平行光化)。但是，關於光束的準直，亦可形成為以在擴束器A4的上游設置為與擴束器A4為另一個的準直透鏡來進行的構成。 ・Beam expander The beam expander A4 is a unit that amplifies the beam diameter of the incident illumination light, and has a plurality of lenses A4a and A4b. An example of the beam expander A4 is a Galilean type that uses a concave lens as lens A4a and a convex lens as lens A4b. The beam expander A4 is equipped with a spacing adjustment mechanism (zoom mechanism) for lenses A4a and A4b, and the magnification of the beam diameter is changed by adjusting the spacing between lenses A4a and A4b. If the illumination light incident on the beam expander A4 is not a parallel beam, it can be collimated (quasi-parallelized) together with the beam diameter by adjusting the spacing between lenses A4a and A4b. However, the collimation of the light beam may be performed by providing a collimating lens separate from the beam expander A4 upstream of the beam expander A4.

其中，擴束器A4係構成為設置在2軸(2自由度)以上的平移載台，且可以中心與所入射的照明光相一致的方式調整位置。此外，在擴束器A4亦配備有2軸(2自由度)以上的傾角調整功能，俾使光軸與所入射的照明光相一致。The beam expander A4 is configured as a translation stage set on more than 2 axes (2 degrees of freedom), and can be adjusted in such a way that the center is consistent with the incident illumination light. In addition, the beam expander A4 is also equipped with a tilt adjustment function on more than 2 axes (2 degrees of freedom) to make the optical axis consistent with the incident illumination light.

此外，雖未特別圖示，在照明光學系統A的光路途中，入射至擴束器A4的照明光的狀態藉由射束監視器予以計測。Although not particularly shown, in the optical path of the illumination optical system A, the state of the illumination light incident on the beam expander A4 is measured by a beam monitor.

・偏光控制單元 偏光控制單元A5係控制照明光的偏光狀態的光學系統，構成為包含1/2波長板A5a及1/4波長板A5b。例如，若將後述的反射鏡A7放入光路而斜向照明試料W時，藉由偏光控制單元A5將照明光形成為P偏光，藉此與P偏光以外的偏光相比，可使來自試料W的表面的散射光量增加。若在試料W的表面有氧化膜，依膜的材質與厚度，可藉由使用S偏光來使來自試料表面的散射光量比P偏光更為增加。對應試料W來選擇偏光，藉此切換容易發生霧度光的條件與不易發生的條件，可使缺陷檢查的感度提升、或使霧度光對試料特性的感度提升。例如若以藉由霧度光所為之輸出來評估試料W的狀態時，將照明光形成為S偏光較為有利。亦可藉由偏光控制單元A5而將照明光形成為圓偏光或形成為P偏光與S偏光的中間的45度偏光。 ・Polarization control unit The polarization control unit A5 is an optical system that controls the polarization state of the illumination light, and is configured to include a 1/2 wavelength plate A5a and a 1/4 wavelength plate A5b. For example, when the reflector A7 described later is placed in the optical path and the sample W is illuminated obliquely, the illumination light is formed into P polarization by the polarization control unit A5, thereby increasing the amount of scattered light from the surface of the sample W compared to polarizations other than P polarization. If there is an oxide film on the surface of the sample W, the amount of scattered light from the sample surface can be increased by using S polarization compared to P polarization, depending on the material and thickness of the film. By selecting the polarization according to the sample W, the conditions where haze light is easy to occur and the conditions where it is not easy to occur are switched, which can improve the sensitivity of defect inspection or improve the sensitivity of haze light to sample characteristics. For example, when evaluating the state of the sample W by the output of the haze light, it is more advantageous to form the illumination light into S polarization. The illumination light can also be formed into circular polarization or 45-degree polarization between P polarization and S polarization by the polarization control unit A5.

・反射鏡 如圖1所示，反射鏡A7係藉由驅動機構(未圖示)朝箭號方向平行移動，對朝向試料W的照明光的光路進行出入。藉此，切換對試料W的照明光的入射路徑。藉由將反射鏡A7***至光路，如上所述由偏光控制單元A5出射的照明光係在反射鏡A7作反射，透過聚光光學單元A6及反射鏡A8且斜向入射至試料W。如上所示使照明光由相對試料W的表面的法線呈傾斜的方向入射至試料W，在本案說明書中記載為「斜入射照明」。另一方面，若將反射鏡A7由光路除外，由偏光控制單元A5出射的照明光係透過反射鏡A9、偏光分光器B’3、偏光控制單元B’2、反射鏡B’1、檢測光學系統B3，垂直入射至試料W。如上所示相對試料W的表面呈垂直使照明光入射，在本案說明書中記載為「垂直照明」。 ・Reflecting mirror As shown in FIG1, the reflecting mirror A7 is moved parallel to the arrow direction by a driving mechanism (not shown) to enter and exit the optical path of the illumination light toward the sample W. In this way, the incident path of the illumination light to the sample W is switched. By inserting the reflecting mirror A7 into the optical path, the illumination light emitted by the polarization control unit A5 as described above is reflected by the reflecting mirror A7, passes through the focusing optical unit A6 and the reflecting mirror A8, and is obliquely incident on the sample W. As shown above, the illumination light is incident on the sample W in an oblique direction relative to the normal line of the surface of the sample W, which is described as "oblique incident illumination" in the specification of this case. On the other hand, if the reflector A7 is excluded from the optical path, the illumination light emitted by the polarization control unit A5 passes through the reflector A9, the polarization beam splitter B'3, the polarization control unit B'2, the reflector B'1, and the detection optical system B3, and is vertically incident on the sample W. As shown above, the illumination light is vertically incident on the surface of the sample W, which is described as "vertical illumination" in the description of this case.

圖5及圖6係表示藉由照明光學系統A由斜方被導至試料W的表面的照明光的光軸與照明強度分布形狀的位置關係的模式圖。圖5係模式表示以入射至試料W的照明光的入射面將試料W切斷的剖面。圖6係模式表示以與入射至試料W的照明光的入射面呈正交且包含試料W的表面的法線的面將試料W切斷的剖面。入射面係指包含入射至試料W的照明光的光軸OA與試料W的表面的法線的面。其中，在圖5及圖6中係將照明光學系統A的一部分抽出表示，例如出射光調整單元A3或反射鏡A7、A8係省略圖示。Fig. 5 and Fig. 6 are schematic diagrams showing the positional relationship between the optical axis of the illumination light guided to the surface of the sample W from the oblique direction by the illumination optical system A and the shape of the illumination intensity distribution. Fig. 5 is a schematic diagram showing a cross section of the sample W cut by the incident plane of the illumination light incident on the sample W. Fig. 6 is a schematic diagram showing a cross section of the sample W cut by a plane that is orthogonal to the incident plane of the illumination light incident on the sample W and includes the normal to the surface of the sample W. The incident plane refers to a plane including the optical axis OA of the illumination light incident on the sample W and the normal to the surface of the sample W. In Fig. 5 and Fig. 6, a part of the illumination optical system A is extracted and shown, and for example, the output light adjustment unit A3 or the reflectors A7 and A8 are omitted from the illustration.

如前述，若將反射鏡A7***至光路，由雷射光源A1被射出的照明光係在聚光光學單元A6被聚光，在反射鏡A8作反射而斜向入射至試料W。如上所示，照明光學系統A係構成為使照明光斜向入射至試料W的表面。該斜入射照明係分別以衰減器A2調整光強度、以擴束器A4調整光束直徑、以偏光控制單元A5調整偏光，在入射面內使照明強度分布均一化。如圖5所示之照明強度分布(照明輪廓)LD1般，形成在試料W的射束點係朝s2方向具有高斯分布狀的光強度分布。As mentioned above, if the reflector A7 is inserted into the optical path, the illumination light emitted by the laser light source A1 is focused by the focusing optical unit A6, reflected by the reflector A8 and incident obliquely on the sample W. As shown above, the illumination optical system A is configured to make the illumination light incident obliquely on the surface of the sample W. The oblique incident illumination is respectively adjusted by the attenuator A2 for light intensity, the beam diameter by the beam expander A4, and the polarization by the polarization control unit A5, so that the illumination intensity distribution is uniform within the incident plane. As shown in the illumination intensity distribution (illumination profile) LD1 in FIG5 , the beam spot on the sample W is formed to have a light intensity distribution with a Gaussian distribution in the direction of s2.

在與入射面及試料表面呈正交的面內，如圖6所示之照明強度分布(照明輪廓)LD2般，射束點係具有相對光軸OA的中心，周邊的強度較弱的光強度分布。該光強度分布係成為例如反映出入射至聚光光學單元A6的光的強度分布的高斯分布、或反映出聚光光學單元A6的開口形狀的類似第一種第一次貝索函數(Bessel function)或sinc函數的強度分布。In the plane orthogonal to the incident plane and the sample surface, the beam spot has a light intensity distribution with weaker intensity at the periphery relative to the center of the optical axis OA, as shown in the illumination intensity distribution (illumination profile) LD2 in Fig. 6. This light intensity distribution is, for example, a Gaussian distribution reflecting the intensity distribution of light incident on the focusing optical unit A6, or an intensity distribution similar to the first order Bessel function or sinc function reflecting the opening shape of the focusing optical unit A6.

此外，斜入射照明對試料W的入射角(相對試料表面的法線的入射光軸的傾斜角)係以反射鏡A7、A8的位置及角度被調整為適於檢測微小缺陷的角度。反射鏡A8的角度係以調整機構A8a予以調整。例如對試料W的照明光的入射角愈大(試料表面與入射光軸所成的照明仰角愈小)，相對於來自試料表面的微小缺陷的散射光成為雜訊的霧度光愈弱。In addition, the incident angle of the oblique incident illumination on the sample W (the inclination angle of the incident light axis relative to the normal line of the sample surface) is adjusted to an angle suitable for detecting micro defects by the position and angle of the reflectors A7 and A8. The angle of the reflector A8 is adjusted by the adjustment mechanism A8a. For example, the larger the incident angle of the illumination light on the sample W (the smaller the illumination elevation angle between the sample surface and the incident light axis), the weaker the haze light that becomes noise relative to the scattered light from the micro defects on the sample surface.

-檢測光學系統- 檢測光學系統Bn(n=1,2…)係將來自試料表面的散射光聚光的單元，構成為包含包括聚光透鏡(接物鏡)的複數光學元件。檢測光學系統Bn的n係檢測光學系統的數量，在本實施例之評估裝置100中係配備有13的檢測光學系統(n=13)。以下若未特別限制而記載為檢測光學系統Bn時，意指檢測光學系統B1-B13之中的任意檢測光學系統。關於感測器Cn、Cn’亦同。但是，檢測光學系統Bn的數量並非限定於13，可適當增減。此外，檢測光學系統Bn的開口(接物鏡)的佈局(layout)亦可適當變更。 -Detection optical system- Detection optical system Bn (n=1,2...) is a unit that focuses scattered light from the sample surface and is composed of multiple optical elements including a focusing lens (objective lens). n in the detection optical system Bn is the number of detection optical systems. In the evaluation device 100 of this embodiment, 13 detection optical systems (n=13) are equipped. When the detection optical system Bn is recorded below without special restrictions, it means any detection optical system among the detection optical systems B1-B13. The same applies to sensors Cn and Cn'. However, the number of detection optical systems Bn is not limited to 13 and can be appropriately increased or decreased. In addition, the layout of the opening (objective lens) of the detection optical system Bn can also be appropriately changed.

圖7係表示由上方觀看，檢測光學系統Bn捕集散射光的區域的圖，對應檢測光學系統Bn的各接物鏡的配置。圖8係模式表示檢測光學系統Bn之中低角及高角的光學系統的天頂角的圖，圖9係表示低角的檢測光學系統的方位角的平面圖，圖10係表示高角的檢測光學系統的方位角的平面圖。Fig. 7 is a diagram showing the area where the detection optical system Bn captures scattered light when viewed from above, corresponding to the arrangement of each objective lens of the detection optical system Bn. Fig. 8 is a diagram schematically showing the zenith angles of the low-angle and high-angle optical systems of the detection optical system Bn, Fig. 9 is a plan view showing the azimuth angle of the low-angle detection optical system, and Fig. 10 is a plan view showing the azimuth angle of the high-angle detection optical system.

在以下說明中，將對試料W的斜入射照明的入射方向作為基準，由上觀看相對試料W的表面上的射束點BS，將入射光的行進方向(圖7中的右方向)設為前方，將相反方向(同左方向)設為後方。相對射束點BS，同圖中的下側為右側，上側為左側。此外，將相對通過射束點BS的試料W的法線N(圖8)，各檢測光學系統Bn的入射光軸(開口的中心線)所成的角ϕ2(圖8)記載為天頂角。此外，將在平面視下相對斜入射照明的入射面，各檢測光學系統Bn的入射光軸(開口的中心線)所成的角ϕ1(圖9、圖10)記載為方位角。In the following description, the incident direction of the oblique incident illumination on the sample W is used as a reference, and the direction of the incident light (right direction in FIG. 7) is set as the front, and the opposite direction (left direction) is set as the rear, relative to the beam point BS on the surface of the sample W viewed from above. Relative to the beam point BS, the lower side in the same figure is the right side, and the upper side is the left side. In addition, the angle φ2 (FIG. 8) formed by the incident light axis (center line of the opening) of each detection optical system Bn relative to the normal N (FIG. 8) of the sample W passing through the beam point BS is recorded as the zenith angle. In addition, the angle φ1 (FIG. 9, FIG. 10) formed by the incident light axis (center line of the opening) of each detection optical system Bn relative to the incident surface of the oblique incident illumination in a plan view is recorded as the azimuth angle.

如圖7-圖10所示，檢測光學系統Bn係配置成對射束點BS的方向(方位角ϕ1或天頂角ϕ2)分別不同。在本實施例中，檢測光學系統Bn的各接物鏡(開口α1-α6、β1-β6、γ)係沿著以對試料W的射束點BS為中心的球(天球)的上半的半球面作配置。入射至開口α1-α6、β1-β6、γ的光在各個所對應的檢測光學系統Bn予以聚光。As shown in Fig. 7 to Fig. 10, the detection optical system Bn is arranged so that the directions (azimuth angle φ1 or zenith angle φ2) of the beam spot BS are different. In this embodiment, each objective lens (opening α1-α6, β1-β6, γ) of the detection optical system Bn is arranged along the upper hemispherical surface of the sphere (celestial sphere) centered on the beam spot BS of the sample W. The light incident on the openings α1-α6, β1-β6, γ is focused by each corresponding detection optical system Bn.

開口γ係與天頂重疊(與法線N相交)，位於形成在試料W的表面的射束點BS的正上方。The opening γ overlaps with the zenith (intersects with the normal N) and is located directly above the beam spot BS formed on the surface of the sample W.

開口α1-α6係將以低角包圍射束點BS的周圍360度的環狀區域進行等分而形成有開口。開口α1-α6係在平面視下由斜入射照明的入射方向以逆時針依開口α1、α2、α3、α4、α5、α6的順序排列。此外，開口α1-α6係避開斜入射照明的入射光路及正反射光路來作佈局。開口α1-α3係相對射束點BS配置在右側，開口α1係位於射束點BS的右後方，開口α2係位於右側方，開口α3係位於右前方。開口α4-α6係相對射束點BS配置在左側，開口α4係位於射束點BS的左前方，開口α5係位於左側方，開口α6係位於左後方。開口α4、α5、α6的配置係針對斜入射照明的入射面，與開口α3、α2、α1呈左右對稱。The openings α1-α6 are formed by equally dividing a 360-degree annular area surrounding the beam spot BS at a low angle. The openings α1-α6 are arranged in the order of openings α1, α2, α3, α4, α5, and α6 in a counterclockwise direction from the incident direction of the oblique incident illumination in a plan view. In addition, the openings α1-α6 are arranged to avoid the incident light path and the regular reflection light path of the oblique incident illumination. The openings α1-α3 are arranged on the right side relative to the beam spot BS, the opening α1 is located at the right rear of the beam spot BS, the opening α2 is located at the right side, and the opening α3 is located at the right front. The openings α4-α6 are arranged on the left side relative to the beam spot BS, the opening α4 is located at the left front of the beam spot BS, the opening α5 is located at the left side, and the opening α6 is located at the left rear. The openings α4, α5, and α6 are arranged with respect to the incident surface of oblique incident illumination, and are bilaterally symmetrical with the openings α3, α2, and α1.

開口β1-β6係將在高角(開口α1-α6與開口γ之間)包圍射束點BS的周圍360度的環狀區域進行等分而形成有開口。開口β1-β6係在平面視下由斜入射照明的入射方向以逆時針依開口β1、β2、β3、β4、β5、β6的順序排列。開口β1-β6之中，開口β1、β4係佈局在與入射面呈交叉的位置，開口β1係相對射束點BS位於後方，開口β4係位於前方。開口β2、β3係相對射束點BS配置在右側，開口β2係位於射束點BS的右後方，開口β3係位於右前方。開口β5、β6係相對射束點BS配置在左側，開口β5係位於射束點BS的左前方，開口β6係位於左後方。The openings β1-β6 are formed by equally dividing the 360-degree annular area surrounding the beam spot BS at a high angle (between the openings α1-α6 and the opening γ). The openings β1-β6 are arranged in the order of openings β1, β2, β3, β4, β5, and β6 in a counterclockwise direction from the incident direction of the oblique incident illumination in a plan view. Among the openings β1-β6, the openings β1 and β4 are arranged at a position intersecting the incident surface, the opening β1 is located at the rear relative to the beam spot BS, and the opening β4 is located at the front. The openings β2 and β3 are arranged on the right side relative to the beam spot BS, the opening β2 is located at the right rear of the beam spot BS, and the opening β3 is located at the right front. The openings β5 and β6 are arranged on the left side relative to the beam spot BS. The opening β5 is located in the left front of the beam spot BS, and the opening β6 is located in the left rear.

由射束點BS朝各種方向散射的散射光入射至開口α1-α6、β1-β6、γ，分別在檢測光學系統Bn被聚光，且被導至相對應的感測器Cn、Cn’。The scattered light scattered in various directions by the beam spot BS is incident on the openings α1-α6, β1-β6, γ, is respectively focused in the detection optical system Bn, and is guided to the corresponding sensors Cn, Cn’.

圖11係將檢測光學系統的構成圖之例抽出表示的模式圖。本實施例之評估裝置100係各檢測光學系統Bn(或一部分檢測光學系統)構成如圖11所示，可以偏光板Bb控制所透過的散射光的偏光方向。具體而言，檢測光學系統Bn係構成為包含：接物鏡(聚光透鏡)Ba、偏光板Bb、偏光分光器Bc、成像透鏡(鏡筒透鏡)Bd、Bd’、視野光圈Be、Be’、感測器Cn、Cn’。FIG11 is a schematic diagram showing an example of the structure of the detection optical system. The evaluation device 100 of this embodiment is that each detection optical system Bn (or a part of the detection optical system) is configured as shown in FIG11, and the polarization direction of the scattered light passing through can be controlled by the polarizer Bb. Specifically, the detection optical system Bn is configured to include: an objective lens (condensing lens) Ba, a polarizer Bb, a polarizing beam splitter Bc, an imaging lens (barrel lens) Bd, Bd', a field aperture Be, Be', and sensors Cn, Cn'.

由試料W入射至檢測光學系統Bn的散射光係在接物鏡Ba被聚光予以準直，且在偏光板Bb控制其偏光方向。偏光板Bb係1/2波長板，可藉由驅動機構(未圖示)作旋轉。藉由控制裝置E1控制驅動機構，且調整偏光板Bb的旋轉角，藉此控制入射至感測器的散射光的偏光方向。The scattered light incident on the detection optical system Bn from the sample W is focused and collimated by the objective lens Ba, and its polarization direction is controlled by the polarizing plate Bb. The polarizing plate Bb is a 1/2 wavelength plate that can be rotated by a driving mechanism (not shown). The driving mechanism is controlled by the control device E1, and the rotation angle of the polarizing plate Bb is adjusted to control the polarization direction of the scattered light incident on the sensor.

在偏光板Bb經偏光控制的散射光係按照偏光方向在偏光分光器Bc分歧光路而入射至成像透鏡Bd、Bd’。藉由偏光板Bb與偏光分光器Bc的組合，任意方向的直線偏光成分被截斷(cut)。若將包含橢圓偏光的任意偏光成分截斷，以可彼此獨立旋轉的1/4波長板與1/2波長板來構成偏光板Bb。The scattered light controlled by polarization on the polarizing plate Bb is incident on the imaging lenses Bd and Bd' after the light paths are divided according to the polarization direction at the polarizing beam splitter Bc. By combining the polarizing plate Bb and the polarizing beam splitter Bc, the linear polarization components in any direction are cut. If any polarization components including elliptical polarization are cut, the polarizing plate Bb is composed of a 1/4 wavelength plate and a 1/2 wavelength plate that can rotate independently of each other.

通過成像透鏡Bd而被聚光的散射照明光係透過視野光圈Be而在感測器Cn予以光電轉換，且其檢測訊號被輸入至訊號處理裝置D。通過成像透鏡Bd’而被聚光的散射照明光係透過視野光圈Be’而在感測器Cn’予以光電轉換，且其檢測訊號被輸入至訊號處理裝置D。視野光圈Be、Be’係配置成其中心與檢測光學系統Bn的光軸相對合，將由遠離試料W的射束點BS的中心的位置所發生的光、在檢測光學系統Bn的內部所發生的迷光等由檢查目的的位置以外所發生的光截斷。藉此具有抑制成為缺陷檢測之妨礙的雜訊的效果。The scattered illumination light collected by the imaging lens Bd is photoelectrically converted by the sensor Cn through the field aperture Be, and its detection signal is input to the signal processing device D. The scattered illumination light collected by the imaging lens Bd' is photoelectrically converted by the sensor Cn' through the field aperture Be', and its detection signal is input to the signal processing device D. The field apertures Be and Be' are arranged so that their centers coincide with the optical axis of the detection optical system Bn, and light generated from a position far from the center of the beam spot BS of the sample W, stray light generated inside the detection optical system Bn, and other light generated from positions other than the inspection target are cut off. This has the effect of suppressing noise that hinders defect detection.

藉由上述構成，針對在同一座標所發生的散射光，可同時檢測彼此正交的2個偏光成分，且在檢測偏光特性不同的複數種類的缺陷或霧度光時為有效。With the above configuration, two polarization components orthogonal to each other can be detected simultaneously for scattered light generated at the same coordinate, and this is effective in detecting multiple types of defects or haze light with different polarization characteristics.

以密集配置的複數透鏡構成接物鏡Ba時，低減因透鏡間的間隙所致之檢測光量的損失，因此如圖11之例所示有將接物鏡Ba的外周部以不會干擾試料W或其他接物鏡的方式形成切口的情形。When the objective lens Ba is composed of a plurality of lenses arranged densely, the loss of the detection light amount due to the gaps between the lenses can be reduced. Therefore, as shown in the example of FIG. 11 , the outer periphery of the objective lens Ba is notched in a manner that does not interfere with the sample W or other objective lenses.

-感測器- 感測器Cn、Cn’係將在相對應的檢測光學系統被聚光的散射光轉換為電訊號而輸出檢測訊號的感測器。感測器C1(C1’)、C2(C2’)、C3(C3’)…係對應檢測光學系統B1、B2、B3…。在該等感測器Cn、Cn’，可使用以高增益將微弱訊號進行光電轉換的例如光電子倍增管、SiPM(矽光電倍增管)等單像素的點感測器。此外，亦有將CCD感測器、CMOS感測器、PSD(位置感測器，Position Sensing Detector)等將複數像素以一微或二微作配列的感測器使用在感測器Cn、Cn’的情形。由感測器Cn、Cn’被輸出的檢測訊號係隨時被輸入至訊號處理裝置D。 -Sensor- Sensors Cn and Cn’ are sensors that convert scattered light focused by the corresponding detection optical system into electrical signals and output detection signals. Sensors C1 (C1’), C2 (C2’), C3 (C3’)… correspond to detection optical systems B1, B2, B3…. For these sensors Cn and Cn’, single-pixel point sensors such as photomultipliers and SiPMs (silicon photomultipliers) that convert weak signals into electricity with high gain can be used. In addition, there are also cases where sensors such as CCD sensors, CMOS sensors, PSDs (position sensors) that arrange multiple pixels in one or two micros are used in sensors Cn and Cn’. The detection signals output by sensors Cn and Cn’ are input to the signal processing device D at any time.

-控制裝置- 控制裝置E1係統括控制評估裝置100的電腦，除了ROM、RAM、其他記憶裝置之外，構成為包含CPU或GPU、FPGA等處理裝置(運算控制裝置)。控制裝置E1係與輸入裝置E2或監視器E3、訊號處理裝置D以有線或無線相連接。輸入裝置E2係使用者將檢查條件的設定等輸入至控制裝置E1的裝置，可適當採用鍵盤或滑鼠、觸控面板等各種輸入裝置。在控制裝置E1係被輸入旋轉載台或平移載台的編碼器的輸出(射束點BS的試料上的rθ座標)、或藉由操作人員透過輸入裝置E2被輸入的檢查條件等。除了試料W的種類或大小、形狀、材質、照明條件、檢測條件等之外，檢查條件係包含例如各感測器Cn、Cn’的感度設定、使用在缺陷判定或老化條件評估(製程裝置的老化條件的評估)的增益值或臨限值。 -Control device- The control device E1 is a computer that controls the evaluation device 100 in an overall manner. In addition to ROM, RAM, and other memory devices, it is configured as a processing device (computation control device) including a CPU, GPU, FPGA, etc. The control device E1 is connected to the input device E2 or the monitor E3, and the signal processing device D by wire or wireless. The input device E2 is a device for the user to input the settings of the inspection conditions, etc. to the control device E1, and various input devices such as a keyboard, a mouse, and a touch panel can be appropriately used. The output of the encoder of the rotating stage or the translation stage (rθ coordinates on the sample of the beam spot BS) or the inspection conditions input by the operator through the input device E2 is input to the control device E1. In addition to the type or size, shape, material, lighting conditions, and detection conditions of the sample W, the inspection conditions include, for example, the sensitivity settings of each sensor Cn, Cn', the gain value or threshold value used in defect determination or aging condition evaluation (evaluation of aging conditions of process equipment).

此外，控制裝置E1係輸出按照檢查條件而對載台ST或照明光學系統A等的動作發出指令的指令訊號、或將與缺陷的檢測訊號同步的射束點BS的座標資料輸出至訊號處理裝置D。控制裝置E1係另外將檢查條件的設定畫面、或試料的檢查資料(檢查畫像等)顯示輸出至監視器E3。檢查資料係除了將各感測器Cn、Cn’的訊號統合而得的最終檢查結果之外，亦可顯示藉由該等感測器Cn、Cn’所得之個別的檢查結果。In addition, the control device E1 outputs a command signal for instructing the operation of the stage ST or the illumination optical system A according to the inspection conditions, or outputs the coordinate data of the beam spot BS synchronized with the defect detection signal to the signal processing device D. The control device E1 also outputs a setting screen for the inspection conditions or a display of the inspection data of the sample (inspection image, etc.) to the monitor E3. The inspection data is not only the final inspection result obtained by integrating the signals of each sensor Cn, Cn', but also the individual inspection results obtained by these sensors Cn, Cn'.

此外，如圖1所示，亦有在控制裝置E1連接缺陷檢查用的電子顯微鏡亦即Review SEM(Review Scanning Electron Microscope)的情形。此時，亦可在控制裝置E1收訊來自Review SEM的缺陷檢查結果的資料，且送訊至訊號處理裝置D。In addition, as shown in FIG1 , there is also a case where the control device E1 is connected to an electron microscope for defect inspection, namely Review SEM (Review Scanning Electron Microscope). In this case, the control device E1 can also receive data of defect inspection results from Review SEM and send the signal to the signal processing device D.

其中，該控制裝置E1係可由與評估裝置100的裝置本體(載台或照明光學系統、檢測光學系統、感測器等)形成單元的單一電腦所構成，亦可由以網路相連接的複數電腦所構成。例如，可形成為在以網路所連接的電腦輸入檢查條件，以附屬於裝置本體的電腦來執行裝置本體或訊號處理裝置D的控制的構成。The control device E1 may be composed of a single computer that forms a unit with the device body (stage or illumination optical system, detection optical system, sensor, etc.) of the evaluation device 100, or may be composed of a plurality of computers connected via a network. For example, a configuration may be formed in which the inspection conditions are input to a computer connected via a network, and the control of the device body or the signal processing device D is executed by a computer attached to the device body.

-訊號處理裝置- 訊號處理裝置D係具有處理由檢測光學系統Bn的感測器Cn、Cn’被輸入的檢測訊號來檢測試料W的缺陷的功能的電腦。訊號處理裝置D係與控制裝置E1相同，除了包含RAM、ROM、HDD、SSD其他記憶裝置的至少1個的記憶體D1(圖12)之外，包含CPU或GPU、FPGA等處理裝置所構成。該訊號處理裝置D係可由與評估裝置100的裝置本體(載台或照明光學系統、檢測光學系統、感測器等)形成單元的單一電腦所構成，亦可由以網路相連接的複數電腦所構成。例如，可形成為以附屬於裝置本體的電腦取得來自裝置本體的缺陷的檢測訊號，視需要將檢測資料加工而送訊至伺服器，在伺服器執行缺陷的檢測或分類等處理的構成。亦考慮形成為以1個電腦兼作訊號處理裝置D與控制裝置E1的構成。 -Signal processing device- The signal processing device D is a computer that has the function of processing the detection signal input by the sensors Cn and Cn' of the detection optical system Bn to detect defects in the sample W. The signal processing device D is the same as the control device E1, and is composed of a processing device such as a CPU or GPU, FPGA, etc. in addition to a memory D1 (Figure 12) including at least one of other memory devices such as RAM, ROM, HDD, and SSD. The signal processing device D can be composed of a single computer that forms a unit with the device body (carrier or illumination optical system, detection optical system, sensor, etc.) of the evaluation device 100, or it can be composed of a plurality of computers connected by a network. For example, a computer attached to the device body can be used to obtain a defect detection signal from the device body, process the detection data as needed, and send it to a server, where the server performs defect detection or classification. It is also possible to use a single computer as both a signal processing device D and a control device E1.

圖12係本發明之第1實施例之老化條件評估裝置所具備的訊號處理裝置D的主要部分的功能區塊圖之一例。如圖12所示，在訊號處理裝置D係配備有：記憶體D1、缺陷判定電路D2、低通濾波器電路D3、老化條件評估電路D4。Fig. 12 is an example of a functional block diagram of the main parts of the signal processing device D of the aging condition evaluation device of the first embodiment of the present invention. As shown in Fig. 12, the signal processing device D is equipped with: a memory D1, a defect judgment circuit D2, a low-pass filter circuit D3, and an aging condition evaluation circuit D4.

掃描試料W中，在訊號處理裝置D，由感測器Cn、Cn’被輸入檢測訊號(散射光強度訊號)，由控制裝置E1被輸入載台ST的編碼器輸出(射束點BS的試料上的rθ座標)。在訊號處理裝置D中，該等檢測訊號與編碼器輸出建立對應，且記錄在記憶體D1。When scanning the sample W, the detection signal (scattered light intensity signal) is input from the sensors Cn and Cn' to the signal processing device D, and is input from the control device E1 to the encoder output of the stage ST (rθ coordinate of the beam spot BS on the sample). In the signal processing device D, the detection signal is associated with the encoder output and recorded in the memory D1.

缺陷判定電路D2係以時間序列順序由記憶體D1讀出由感測器Cn、Cn’被輸入的檢測訊號，依序判定該等檢測訊號是否為檢測到缺陷的缺陷訊號，將判定結果記錄在記憶體D1或記憶裝置DB，而且輸出至控制裝置E1。在缺陷判定電路D2中，抽出例如檢測訊號的高頻成分作為關於異物等缺陷的缺陷訊號。高頻成分係指變動頻率高的成分，具體而言為值的時間變動超過預先設定的設定值的成分。控制裝置E1係按照伴隨操作人員的操作所輸入的來自輸入裝置E2的操作訊號或自動地在監視器E3顯示輸出判定結果。The defect judgment circuit D2 reads the detection signals input by the sensors Cn and Cn' from the memory D1 in a time series order, and judges in sequence whether the detection signals are defect signals of detected defects, records the judgment results in the memory D1 or the memory device DB, and outputs them to the control device E1. In the defect judgment circuit D2, for example, high-frequency components of the detection signal are extracted as defect signals related to defects such as foreign matter. High-frequency components refer to components with high frequency of variation, specifically, components whose time variation of values exceeds a preset set value. The control device E1 outputs the judgment results according to the operation signal from the input device E2 input by the accompanying operator's operation or automatically displays them on the monitor E3.

低通濾波器電路D3係以時間序列順序由記憶體D1讀出來自感測器Cn、Cn’的檢測訊號，針對試料W的各區域抽出除了缺陷訊號之外的霧度訊號，作成在試料W的表面的霧度訊號加上座標資訊的全面的光強度分布亦即霧度圖(haze map)。霧度訊號係在由試料所得的光的訊號之中主要指低頻成分，主要為起因於試料的特性的訊號。在此，例如抽出檢測訊號的低頻成分，亦即變動頻率(訊號強度的時間變動)低於預先設定的設定值的成分作為霧度訊號。光學缺陷檢查裝置係可高速掃描，因此可抽出對試料全面的霧度訊號、或根據此的霧度圖。但是，亦可考慮並非試料全面，而欲部分診斷試料的情形。此時，以抽出霧度訊號的區域而言，亦可為取樣點，亦可分為以任意網格大小的網格狀的篩網(mesh)作區劃的區域來抽出霧度訊號。The low-pass filter circuit D3 reads the detection signals from the sensors Cn and Cn' from the memory D1 in a time series order, extracts the haze signal except the defect signal for each area of the sample W, and creates a haze map, which is a comprehensive light intensity distribution including the haze signal on the surface of the sample W and the coordinate information. The haze signal mainly refers to the low-frequency component in the light signal obtained from the sample, and is mainly a signal caused by the characteristics of the sample. Here, for example, the low-frequency component of the detection signal, that is, the component with a variation frequency (temporal variation of the signal intensity) lower than a preset setting value, is extracted as the haze signal. The optical defect inspection device can scan at high speed, so it can extract the haze signal of the entire sample, or a haze map based on it. However, it is also possible to consider the case where the sample is not fully tested, but a partial test is required. In this case, the area from which the haze signal is extracted may be a sampling point, or the area may be divided into areas demarcated by a mesh of any mesh size to extract the haze signal.

若分為以網格狀的篩網作區劃的區域來抽出霧度訊號時，針對1個區域取得複數霧度訊號。可將該等複數霧度訊號的統計值(平均值、中央值等)作為該區域的霧度訊號。區劃區域的篩網的1邊係可設定為例如1mm-數mm程度。亦取決於篩網的大小，若為例如1mm篩網，試料表面係被分割為超過6萬的區域，生成精細的霧度圖。因此，在霧度圖係包含按試料W的每個區域的霧度光的強度資料。但是，篩網的大小並不一定愈小愈好，以所需充分範圍將篩網設定較大，藉此可按照試料表面的區域數的減少來抑制訊號處理裝置D的運算負荷。When extracting the haze signal by dividing the area into zones with a grid-shaped screen, multiple haze signals are obtained for one area. The statistical values (average value, median value, etc.) of these multiple haze signals can be used as the haze signal of the area. One side of the screen that divides the area can be set to, for example, 1mm to several mm. It also depends on the size of the screen. If it is, for example, a 1mm screen, the sample surface is divided into more than 60,000 areas to generate a detailed haze map. Therefore, the haze map contains the intensity data of the haze light for each area of the sample W. However, the size of the screen is not necessarily the smaller the better. By setting the screen larger within the required sufficient range, the computational load of the signal processing device D can be suppressed according to the reduction in the number of areas on the sample surface.

老化條件評估電路D4係根據在低通濾波器電路D3被抽出的霧度訊號，評估處理了試料W的製程裝置的老化條件。老化條件係將在製程裝置中伴隨老化處理被處理的1批次的試料之中至少第1片被處理的試料W的全面或每個區域的霧度訊號與對應的區域的基準霧度訊號作比較予以評估。亦可以霧度圖的形式來作比較。亦即，訊號處理裝置D係根據霧度訊號及基準霧度訊號的差，來感測形成為第1片試料W的微觀表面形狀所表現的製程裝置的腔室的狀況的變化。但是，並不需要將第2片之後被處理的試料W的霧度訊號與基準霧度訊號的比較處理排除。The aging condition evaluation circuit D4 evaluates the aging condition of the process device that processes the sample W based on the haze signal extracted in the low-pass filter circuit D3. The aging condition is evaluated by comparing the haze signal of the entirety or each region of at least the first sample W processed in a batch of samples processed with the aging treatment in the process device with the reference haze signal of the corresponding region. The comparison can also be made in the form of a haze map. That is, the signal processing device D senses the change in the condition of the chamber of the process device represented by the microscopic surface shape of the first sample W based on the difference between the haze signal and the reference haze signal. However, it is not necessary to exclude the comparison process of the haze signal of the sample W processed after the second sheet and the reference haze signal.

具體而言，針對第1片試料W的全面或經分割的各區域，將霧度訊號與對應區域的基準霧度訊號作比較，若霧度訊號及基準霧度訊號的差分超過預先設定的設定值、或區域數超過容許值時，推定老化條件的不完備。亦可採用生成有關在試料W所得的霧度訊號的霧度圖與有關基準霧度訊號的霧度圖的差分畫像，以霧度訊號及基準霧度訊號的差(亮度差)進行同樣的判定的演算法。Specifically, the haze signal is compared with the reference haze signal of the corresponding area for the entire or divided area of the first sample W. If the difference between the haze signal and the reference haze signal exceeds a preset setting value or the number of areas exceeds an allowable value, it is estimated that the aging condition is incomplete. Alternatively, an algorithm may be used to generate a difference image between a haze map related to the haze signal obtained on the sample W and a haze map related to the reference haze signal, and perform the same judgment based on the difference (brightness difference) between the haze signal and the reference haze signal.

其中，老化條件評估電路D4係針對被適用在製程裝置的老化條件的評估結果，在監視器E3顯示輸出資訊。例如，老化條件的評估結果係被記錄在記憶體D1或記憶裝置DB，並且被輸出至控制裝置E1。控制裝置E1係按照伴隨操作人員的操作所輸入的來自輸入裝置E2的操作訊號或自動地在監視器E3顯示輸出評估結果。The aging condition evaluation circuit D4 displays output information on the monitor E3 for the evaluation result of the aging condition applied to the process device. For example, the evaluation result of the aging condition is recorded in the memory D1 or the memory device DB, and is output to the control device E1. The control device E1 displays the output evaluation result on the monitor E3 according to the operation signal from the input device E2 input by the accompanying operator's operation or automatically.

此外，在製程裝置的老化條件不完備的早期掌握的觀點中，較宜為以訊號處理裝置D逐次處理伴隨試料W的缺陷檢查而由感測器Cn、Cn’被輸入的檢測訊號來評估老化條件。但是，亦可形成為將以試料W的全面的掃描所取得的檢測訊號暫時保存在記憶裝置DB，以所希望的時序(例如每天定時)事後處理所保存的資料來評估老化條件的構成。Furthermore, from the perspective of early understanding of the aging conditions of the process equipment, which are not complete, it is preferable to evaluate the aging conditions by sequentially processing the detection signals inputted from the sensors Cn and Cn' accompanying the defect inspection of the sample W with the signal processing device D. However, it is also possible to temporarily store the detection signals obtained by the overall scanning of the sample W in the memory device DB, and then process the stored data at a desired time sequence (for example, at a fixed time every day) to evaluate the aging conditions.

此外，老化條件評估電路D4係具有設定任意製程裝置的適當老化條件且進行提示的功能。該功能係若在例如新設計半導體晶圓的製造線時、在既有的製造線導入新的製程裝置時、在既有的製造線製造新的半導體時等，有用於重新決定適當的老化條件時。若設定適當老化條件，老化條件評估電路D4係進行複數老化條件的評估及比較。具體而言，若新決定老化條件，老化條件評估電路D4係將在製程裝置伴隨條件分別不同的老化處理所處理的複數批次的各第1片試料W的霧度訊號分別與基準霧度訊號作比較。分別適用在該等複數批次的老化條件成為最終設定的適當老化條件的候補。成為適當老化條件的候補的係在例如設定目標為妥當的基礎條件，加上適當調整基礎條件的各參數所設定的變化的條件的複數老化條件。接著，老化條件評估電路D4係將霧度訊號與基準霧度訊號的差在容許值內而且適用於最小試料W所屬批次的老化條件設定為適當老化條件，且顯示輸出在例如監視器E3。In addition, the aging condition evaluation circuit D4 has the function of setting appropriate aging conditions for any process device and providing prompts. This function is useful for re-determining appropriate aging conditions, for example, when a new semiconductor wafer manufacturing line is newly designed, when a new process device is introduced into an existing manufacturing line, when a new semiconductor is manufactured in an existing manufacturing line, etc. If appropriate aging conditions are set, the aging condition evaluation circuit D4 evaluates and compares multiple aging conditions. Specifically, if the aging conditions are newly determined, the aging condition evaluation circuit D4 compares the mist signal of each first sample W of multiple batches processed by aging treatments with different conditions in the process device with the reference mist signal. The aging conditions applied to these multiple batches become candidates for the appropriate aging conditions that are finally set. The candidate for the appropriate aging condition is a plurality of aging conditions that are set as appropriate basic conditions, for example, and the conditions for changes set by appropriately adjusting the parameters of the basic conditions. Then, the aging condition evaluation circuit D4 sets the aging condition that is applicable to the batch to which the minimum sample W belongs and the difference between the mist signal and the reference mist signal is within the allowable value as the appropriate aging condition, and displays the output on, for example, the monitor E3.

-基準霧度訊號- 在本實施例中，使用在老化條件的評估的基準霧度訊號係針對感測器Cn、Cn’的各個，按試料W的表面的全面或每個預定的區域(在本實施例中為rθ座標)作規定，且儲存在例如記憶裝置DB。亦即，針對感測器C、C’的各個，準備成為基準的霧度圖。針對同一感測器所規定的基準霧度訊號亦可按每個試料W的區域不同。 - Reference haze signal - In this embodiment, the reference haze signal used in the evaluation of aging conditions is specified for each of the sensors Cn and Cn' according to the entire surface of the sample W or each predetermined area (rθ coordinates in this embodiment), and is stored in, for example, a memory device DB. That is, a reference haze map is prepared for each of the sensors C and C'. The reference haze signal specified for the same sensor may also be different for each area of the sample W.

在基準霧度訊號係可使用掃描例如以作為評估對象的老化條件被老化處理的1批次的試料W之中最後被處理的試料W(第N片試料W)而得的實測值。此外，不限於最後被處理的試料W，亦可將對製程裝置的狀況呈安定的批次後半的任意的試料W進行實測後的值、或後半(包含最後)被處理的複數試料W的實測值的統計值(平均值或中央值等)，作為基準霧度訊號。此外，基準霧度訊號亦可為例如掃描基準試料而得者。基準試料係在品質檢查中適合基準的試料，較佳為與試料W為同一種類且與試料W為相同工程的試料。此外，基準霧度訊號並非為基準試料的測定，亦可藉由天天運算針對作良品判定的試料(製品或半製品)在半導體製造製程中以評估裝置100所得的霧度訊號的統計資料(例如平均值、中央值)來進行設定。此外，亦可模擬根據試料W的設計資料而按每個檢測光學系統Bn所得的霧度訊號來設定基準霧度訊號。亦即，亦可採用實績值或理論值作為基準霧度訊號。The reference mist signal may be a measured value obtained by scanning, for example, the last processed sample W (Nth sample W) among a batch of samples W that have been aged under the aging conditions to be evaluated. In addition, not limited to the last processed sample W, the value after measuring any sample W in the second half of the batch where the condition of the process device is stable, or the statistical value (average value or median value, etc.) of the measured values of multiple samples W processed in the second half (including the last) may be used as the reference mist signal. In addition, the reference mist signal may be obtained, for example, by scanning a reference sample. The reference sample is a sample that is suitable for the reference in quality inspection, preferably a sample of the same type as the sample W and of the same process as the sample W. In addition, the reference haze signal is not a measurement of the reference sample, but can also be set by calculating the statistical data (such as the average value, the median value) of the haze signal obtained by the evaluation device 100 in the semiconductor manufacturing process for the sample (finished product or semi-finished product) for daily judgment of good products. In addition, the reference haze signal can also be set according to the haze signal obtained by each detection optical system Bn based on the design data of the sample W. That is, the actual value or the theoretical value can also be used as the reference haze signal.

此外，試料W的霧度圖(包含所實測的基準霧度訊號)係可以利用在評估裝置100中的試料W的缺陷檢查時的掃描所得的霧度訊號來作成。但是，一般而言，由於在缺陷檢查適用不易發生霧度光的檢查條件，因此亦假想無法充分檢測評估老化條件所需強度的霧度光的情形。此時，亦可針對尤其使用在老化條件的評估的試料W，例如第1片與第N片試料W，有別於缺陷檢查，以容易發生霧度光的條件掃描試料W來取得霧度圖。In addition, the haze map of the sample W (including the measured reference haze signal) can be prepared using the haze signal obtained by scanning the sample W in the evaluation device 100 during the defect inspection. However, in general, since the inspection conditions in which haze light is not easy to be generated are applied in the defect inspection, it is also assumed that the haze light of the intensity required for the evaluation of the aging condition cannot be fully detected. In this case, for the sample W used in the evaluation of the aging condition, for example, the first and Nth samples W, the haze map can be obtained by scanning the sample W under the condition in which haze light is easy to be generated, which is different from the defect inspection.

-相關資料- 此外，在記憶裝置DB，連同基準霧度訊號一起預先儲存有檢測光學系統Bn(換言之為霧度光的出射方向)與霧度訊號的變動要因的相關。 -Related information- In addition, the memory device DB stores the correlation between the detection optical system Bn (in other words, the emission direction of the haze light) and the factors causing the haze signal to change, along with the reference haze signal.

在半導體製造工程中，進行電漿處理的工程係有幾十個工程。材料(試料的膜質、或在腔室內所使用的氣體等的種類等)或處理條件按每個該工程而異。在經蝕刻處理之後的試料W中，若有在表面粗糙度容易出現變化的工程，亦有在表面膜厚容易出現變化的工程。或者，亦有配合在製程裝置的腔室內的氣體流動的方向而容易出現具特徵的傾向的情形。「容易變動的參數」按每個工程而異。因此，評估裝置100較宜為按照容易變動的參數，使用容易捕捉該變化的檢測器的訊號來評估老化條件。In the semiconductor manufacturing process, there are dozens of processes that perform plasma treatment. The materials (film quality of the sample, or the type of gas used in the chamber, etc.) or processing conditions vary for each process. In the sample W after the etching process, there are processes in which the surface roughness is prone to change, and there are also processes in which the surface film thickness is prone to change. Alternatively, there are also situations in which a characteristic inclination is prone to appear in accordance with the direction of gas flow in the chamber of the process device. "Parameters that are prone to change" vary for each process. Therefore, the evaluation device 100 is preferably used to evaluate the aging conditions according to the parameters that are prone to change, using the signal of a detector that is easy to capture the change.

例如，若試料W的表面粗糙度容易在某範圍內變動，有形成為主要入射至相對射束點BS位於照明光的正反射方向的開口α3、α4的散射光強度的變化而出現的傾向。此外，若試料W的表面膜厚容易在某範圍內變動，有形成為主要入射至相對射束點BS位於與正反射方向為相反側的開口α1、α6的散射光強度的變化而出現的傾向。根據如上所示之關係，對應工程的變動要因、與對該變動要因為感度高的檢測光學系統建立關連，作為相關資料而儲存在記憶裝置DB。藉由訊號處理裝置D，根據該相關資料，選擇特定的檢測光學系統Bn，且監視針對伴隨老化處理的批次的第1片試料W所選擇出的檢測光學系統Bn的霧度訊號，藉此精度佳地評估製程裝置的老化條件。For example, if the surface roughness of the sample W is prone to change within a certain range, there is a tendency to appear as a change in the intensity of scattered light mainly incident on the openings α3 and α4 located in the direction of regular reflection of the illumination light at the relative beam point BS. In addition, if the surface film thickness of the sample W is prone to change within a certain range, there is a tendency to appear as a change in the intensity of scattered light mainly incident on the openings α1 and α6 located on the opposite side of the relative beam point BS to the regular reflection direction. Based on the relationship shown above, the variation factor of the corresponding process is associated with the detection optical system that is highly sensitive to the variation factor, and is stored as related data in the storage device DB. By using the signal processing device D, a specific detection optical system Bn is selected based on the relevant data, and the haze signal of the detection optical system Bn selected for the first sample W of the batch accompanied by aging treatment is monitored, thereby accurately evaluating the aging conditions of the process equipment.

其中，上述相關資料僅為霧度訊號的變動要因與檢測光學系統Bn的相關之一例。若在例如在對應開口α3、α4、α1、α6的檢測光學系統Bn以外的檢測光學系統所取得的霧度訊號出現製程裝置的狀況的變化有卓見時，亦可根據該卓見來設定相關資料。此外，亦有不限於在檢測光學系統Bn被個別檢測的霧度訊號，而在複數檢測光學系統Bn被檢測的霧度訊號的差分或合計，出現製程裝置的狀況的變化的可能性。此時，規定根據該相關的相關資料，將在複數檢測光學系統Bn被檢測的霧度訊號的差分或合計作為霧度訊號的一形態，與有關相同檢測光學系統Bn的組的基準霧度訊號的差分或合計相比較，可使用在老化條件的評估。The above-mentioned related data is only one example of the correlation between the change factor of the haze signal and the detection optical system Bn. If there is a good understanding of the change of the state of the process device in the haze signal obtained by the detection optical system other than the detection optical system Bn corresponding to the openings α3, α4, α1, and α6, the related data can also be set based on the good understanding. In addition, there is also the possibility that the change of the state of the process device occurs not only in the haze signal detected individually by the detection optical system Bn, but also in the difference or sum of the haze signals detected by the multiple detection optical systems Bn. At this time, it is stipulated that based on the relevant relevant data, the difference or sum of the haze signals detected in the multiple detection optical systems Bn is used as a form of haze signal, and compared with the difference or sum of the reference haze signals of the group related to the same detection optical system Bn, which can be used for evaluation under aging conditions.

訊號處理裝置D係在老化條件評估時，由記憶裝置DB讀入上述相關資料，且自動選擇與製程裝置的老化條件的評估相關的檢測光學系統。但是，訊號處理裝置D亦可按照操作人員透過輸入裝置E2所進行的指定來選擇檢測光學系統。接著，訊號處理裝置D係根據由所選擇出的檢測光學系統被輸出的霧度訊號，評估製程裝置的老化條件。例如，若仿效前述例，訊號處理裝置D係選擇對應相對射束點BS位於照明光的正反射方向的開口α3、α4、α1、α6的檢測光學系統Bn。由在對應開口α3、α4的檢測光學系統Bn被檢測的霧度訊號與其基準霧度訊號的差分，感測試料W的表面粗糙度的預定範圍的變化、進而有關該預定範圍的表面粗糙度的變化的製程裝置的狀況的變化。由對應開口α1、α6的檢測光學系統Bn的霧度訊號與其基準霧度訊號的差分，感測試料W的表面膜厚的預定範圍的變化，進而有關該表面膜厚的預定範圍的變化的製程裝置的狀況的變化。When evaluating the aging condition, the signal processing device D reads the above-mentioned related data from the memory device DB and automatically selects the detection optical system related to the evaluation of the aging condition of the process device. However, the signal processing device D can also select the detection optical system according to the designation made by the operator through the input device E2. Then, the signal processing device D evaluates the aging condition of the process device based on the haze signal output by the selected detection optical system. For example, if following the above example, the signal processing device D selects the detection optical system Bn corresponding to the openings α3, α4, α1, α6 located in the regular reflection direction of the illumination light relative to the beam point BS. By the difference between the haze signal detected by the detection optical system Bn corresponding to the openings α3 and α4 and its reference haze signal, the change in the predetermined range of the surface roughness of the sample W and the change in the state of the process device related to the change in the predetermined range of the surface roughness are sensed. By the difference between the haze signal of the detection optical system Bn corresponding to the openings α1 and α6 and its reference haze signal, the change in the predetermined range of the surface film thickness of the sample W and the change in the state of the process device related to the change in the predetermined range of the surface film thickness are sensed.

此外，即使為入射至同一檢測光學系統Bn的霧度光，亦有依偏光方向，伴隨老化條件不完備的狀況變動的出現方式不同的可能性。此點，在本實施例中，檢測光學系統Bn係具備有：分別對應偏光方向將光分離的偏光分光器Bc；及分別檢測在偏光分光器Bc被分離的偏光方向不同的光的複數感測器Cn、Cn’(圖11)。因此，若為本實施例之情形，在各檢測光學系統Bn中，針對試料上的同一座標，可取得偏光方向不同的2個霧度訊號。因此，可加上霧度光的偏光方向，作為前述霧度訊號的變動要因與檢測光學系統Bn的相關資料的參數，規定更精細的霧度訊號及其變動要因的關係，且儲存在記憶裝置DB。如此因相關資料的參數增加，可由霧度訊號更精彩地感測製程裝置的狀況的變化。針對伴隨老化條件被處理的批次的第1片試料W，精度佳地感測製程裝置的狀況的變化，藉此可精彩地評估老化條件。In addition, even if the haze light is incident on the same detection optical system Bn, there is a possibility that the appearance is different depending on the polarization direction, accompanying the change of the aging conditions. In this regard, in this embodiment, the detection optical system Bn is equipped with: a polarization beam splitter Bc that separates the light corresponding to the polarization direction; and a plurality of sensors Cn, Cn' (Figure 11) that detect the light with different polarization directions separated by the polarization beam splitter Bc. Therefore, in the case of this embodiment, in each detection optical system Bn, two haze signals with different polarization directions can be obtained for the same coordinate on the sample. Therefore, the polarization direction of the haze light can be added as a parameter of the above-mentioned change factor of the haze signal and the related data of the detection optical system Bn, and a more precise relationship between the haze signal and its change factor can be specified and stored in the memory device DB. In this way, due to the increase in the parameters of the related data, the change of the condition of the process device can be more accurately sensed by the haze signal. For the first sample W of the batch processed with aging conditions, the change of the condition of the process device can be accurately sensed, thereby accurately evaluating the aging conditions.

此外，在製程裝置的狀況與試料W上的位置之間亦可能存在相關。在電漿製程裝置經處理的試料W上，可以霧度圖來特定對使用在取得基準霧度訊號的試料為變化大的區域(某些發生完成結果不良的可能性高的區域)。若檢測到老化條件的不完備，可著重在試料上的該區域，以該區域的霧度訊號與基準霧度訊號的差分消失的方式，重新研究老化條件參數。亦考慮特定霧度訊號與參數的相關，且在評估裝置100中，按照不良區域的霧度訊號與基準霧度訊號的差分，自動運算所被推薦的老化條件的參數調整，且提示給監視器E3。In addition, there may be a correlation between the condition of the process device and the position on the sample W. On the sample W processed by the plasma process device, the haze map can be used to identify the areas where the sample used to obtain the reference haze signal has a large change (certain areas with a high probability of poor completion results). If the aging condition is detected to be incomplete, the area on the sample can be focused on, and the aging condition parameters can be re-examined in a way that the difference between the haze signal in the area and the reference haze signal disappears. The correlation between the specific haze signal and the parameter is also considered, and in the evaluation device 100, the parameter adjustment of the recommended aging condition is automatically calculated according to the difference between the haze signal in the bad area and the reference haze signal, and the monitor E3 is prompted.

-老化條件的決定及運用- 在此，圖13係表示由半導體的研究開發至製造(High Volume Manufacturing)的工程中評估製程裝置的老化條件的典型場面的流程圖。在圖13所示之步驟S100-S600之中，步驟S100-S300為半導體的研究開發線的工程，步驟S400-S600為半導體製造線的工程。 -Determination and application of aging conditions- Here, FIG. 13 is a flowchart showing a typical scenario of evaluating the aging conditions of process equipment in the process from semiconductor research and development to manufacturing (High Volume Manufacturing). Among the steps S100-S600 shown in FIG. 13, steps S100-S300 are the processes of the semiconductor research and development line, and steps S400-S600 are the processes of the semiconductor manufacturing line.

步驟S100 在步驟S100中，在製程裝置的製造商中，針對製程裝置，抽出成為最終老化條件的候補的候補條件。即使為同型的製程裝置，老化條件係依所使用的工程或所處理的試料W的種類等而異。在該階段，首先按照預定的工程或試料W的種類，設定用以在製程裝置將試料W進行加工處理(例如蝕刻、成膜、研磨等)的製程條件。老化條件係按照先行設定的製程條件來作設定。亦即，在目的的製程裝置中，以所設定的製程條件，由最初或前次的處理隔著預定時間以上的間隔來處理複數片試料W時，以在該等複數片試料W的處理狀態不發生不均的方式，設定老化條件。在此，為了設定老化條件，試行複數候補條件。以候補條件而言，如前述，除了對應使用製程裝置的工程或所處理的試料W的種類等的基礎條件之外，準備將基礎條件的各參數微細變更的複數變化的條件。以參數之例而言，有微波或電漿放電時間、氣體流量等。接著，在製程裝置伴隨各候補條件的老化處理以預定的製程條件處理試料W，且將第1片試料W與基準試料(例如第N片試料W)的處理狀態作比較。結果，以處理狀態的差在容許值內為前提，處理狀態的不均最少的候補條件被設定作為目的的製程裝置的老化條件，且提示給半導體的製造商。若無取得良好結果的老化條件，另外試行不同的老化條件。 Step S100 In step S100, the manufacturer of the process device extracts candidate conditions that become candidates for the final aging conditions for the process device. Even for the same type of process device, the aging conditions vary depending on the process used or the type of sample W processed. In this stage, first, according to the predetermined process or type of sample W, the process conditions for processing the sample W in the process device (such as etching, film formation, grinding, etc.) are set. The aging conditions are set according to the previously set process conditions. That is, in the target process device, when a plurality of samples W are processed at intervals of a predetermined time or more from the initial or previous processing under the set process conditions, the aging conditions are set in such a way that the processing states of the plurality of samples W do not vary. Here, in order to set the aging conditions, a plurality of candidate conditions are tried. As for the candidate conditions, as mentioned above, in addition to the basic conditions corresponding to the process in which the process device is used or the type of sample W to be processed, a plurality of changed conditions are prepared by slightly changing the parameters of the basic conditions. Examples of the parameters include microwave or plasma discharge time, gas flow rate, etc. Next, the sample W is processed with the predetermined process conditions in the process device along with the aging treatment of each candidate condition, and the processing state of the first sample W is compared with that of the reference sample (e.g., the Nth sample W). As a result, the candidate condition with the least uneven processing state is set as the aging condition of the target process device, provided that the difference in processing state is within the allowable value, and is prompted to the semiconductor manufacturer. If no aging condition obtains good results, a different aging condition is tried.

步驟S200 在接續的步驟S200中，在使用製程裝置的半導體的製造商中，由製程裝置的製造商所提示的老化條件在適用於半導體的製造線之前予以調整。在該工程中，以由製程裝置的製造商所提示的老化條件為基本，除了對應實際上流至製造線的批次間的間隔(製程裝置的待機時間)的調整之外，設定老化條件。接著，對應製程裝置的待機時間，以在製程裝置中被設定的條件進行老化處理及試料W的批次的處理，與步驟S100同樣地將各第1片試料W與基準試料的處理狀態作比較來確認差在容許值內。若有差不在容許值內的批次，調整針對有關該批次之待機時間的老化條件，反覆試行至設定差在容許值內的老化條件為止。批次係指作為N=最小2的複數片試料的套組(set)。使用在條件設定/調整的試料宜少即可。 Step S200 In the subsequent step S200, in the semiconductor manufacturer using the process device, the aging conditions suggested by the manufacturer of the process device are adjusted before being applied to the semiconductor manufacturing line. In this process, the aging conditions are set based on the aging conditions suggested by the manufacturer of the process device, in addition to the adjustment corresponding to the interval between batches actually flowing to the manufacturing line (the waiting time of the process device). Then, according to the waiting time of the process device, the aging treatment and the batch treatment of the sample W are performed under the conditions set in the process device, and the processing status of each first sample W is compared with the reference sample in the same way as step S100 to confirm that the difference is within the allowable value. If there are batches whose differences are not within the allowable value, adjust the aging conditions for the standby time of the batch, and repeat the test until the aging conditions with differences within the allowable value are set. A batch refers to a set of multiple samples with N = minimum 2. It is better to use fewer samples in condition setting/adjustment.

步驟S300 步驟S300係適用於在步驟S200所設定的老化條件的製造線之前的最終確認試驗。在製造線或模擬製造線的設備試行所設定的各老化條件，以與步驟S100、S200相同的要領將處理後的試料W的處理狀態進行比較。若可確認各第1片試料W與基準試料的處理狀態的差在容許值內，決定在此試行的老化條件(套組)作為針對目的的製程裝置的最終老化條件。假設差不在容許值內時，返回至步驟S200，再設定老化條件的套組(set)。 Step S300 Step S300 is the final confirmation test before the manufacturing line for the aging conditions set in step S200. The aging conditions set in the equipment trial of the manufacturing line or the simulated manufacturing line are compared with the processing status of the processed samples W in the same way as steps S100 and S200. If it can be confirmed that the difference between the processing status of each first sample W and the reference sample is within the allowable value, the aging conditions (set) tested here are determined as the final aging conditions for the target process equipment. If the difference is not within the allowable value, return to step S200 and set the set of aging conditions again.

步驟S400 步驟S400係將在研究開發線所決定的老化條件適用在半導體的製造線，且開始運用的工程。此之後，在製造線中，必要時在製程裝置執行對應待機時間的條件的老化處理。在製程裝置被處理的試料W係在線內(In-line)進行缺陷檢查。此外，視需要，供作老化處理的適當與否等的檢查。 Step S400 Step S400 is a process to apply the aging conditions determined in the research and development line to the semiconductor manufacturing line and start the operation. After that, in the manufacturing line, if necessary, the process equipment performs aging treatment under conditions corresponding to the standby time. The sample W processed in the process equipment is inspected for defects in-line. In addition, if necessary, the appropriateness of the aging treatment is checked.

步驟S500、S600 適用於半導體的製造線的老化條件的適當與否係在半導體的製造過程中亦適當(例如定期或適時)檢查(步驟S500)。若試料W的處理狀態良好，製造線係繼續運轉，若由試料W的處理狀態懷疑老化條件的不完備時，調整老化條件(步驟S600)。調整老化條件時，必要的情形下係停止進行調整的該製程裝置，且若可調整老化條件，即重新進行運轉。 Steps S500, S600 The suitability of the aging conditions for the semiconductor manufacturing line is also appropriately (e.g., regularly or timely) checked during the semiconductor manufacturing process (step S500). If the processing status of the sample W is good, the manufacturing line continues to operate. If the processing status of the sample W suspects that the aging conditions are incomplete, the aging conditions are adjusted (step S600). When adjusting the aging conditions, the process device for adjustment is stopped if necessary, and if the aging conditions can be adjusted, the operation is resumed.

-老化條件評估的流程- 在此，圖14係表示製程裝置的老化條件評估的流程之例的模式流程圖。圖14的流程係以在例如圖13的步驟S100-S300的半導體的研究開發階段所進行的老化條件的評估、及在步驟S500、S600的半導體的製造階段所進行的老化條件的評估來適當實施。在此，列舉電漿蝕刻裝置作為製程裝置的具體例來作說明。 -Aging condition evaluation process- Here, FIG. 14 is a schematic flow chart showing an example of the process of aging condition evaluation of a process device. The process of FIG. 14 is appropriately implemented by evaluating aging conditions in the research and development stage of semiconductors, such as steps S100-S300 of FIG. 13, and evaluating aging conditions in the manufacturing stage of semiconductors, such as steps S500 and S600. Here, a plasma etching device is cited as a specific example of a process device for explanation.

在圖14的流程中，首先在電漿蝕刻裝置中，伴隨作為評估對象的老化條件的老化處理，試料W的批次被電漿蝕刻處理(步驟S10)。In the flow of FIG. 14 , first, in a plasma etching apparatus, a batch of samples W are subjected to a plasma etching process accompanied by an aging process under an aging condition to be evaluated (step S10 ).

本實施例之情形下，使用亦為光學式缺陷檢查裝置的評估裝置100，在線內實施在電漿蝕刻裝置被處理的試料W的批次的缺陷檢查。「在線內」意指“作為半導體製造的一工程”、或“在半導體研究開發/製造線的過程”。此時，藉由前述之訊號處理裝置D(圖12)，根據在該批次之中至少在電漿蝕刻裝置處理為第1片的試料W所得的霧度訊號，評估適用於電漿蝕刻裝置的老化條件的妥當性(步驟S21)。使用在該老化條件的評估的霧度訊號亦可使用在試料W的缺陷檢查時所得的霧度訊號，亦可使用在缺陷檢查之前或之後以容易檢測霧度光的條件掃描試料W而得的霧度訊號。接著，在評估裝置100中，在試料W所得的霧度訊號與基準霧度訊號作比較，且判定兩者的差分是否在基準範圍(步驟S22)。容後敘述有關步驟S21、S22之藉由評估裝置100所為之老化條件評估的詳細例。In the case of this embodiment, the evaluation device 100, which is also an optical defect inspection device, is used to perform defect inspection of a batch of samples W processed in a plasma etching device in-line. "In-line" means "as a process of semiconductor manufacturing" or "in a process of a semiconductor research and development/manufacturing line". At this time, the appropriateness of the aging conditions applied to the plasma etching device is evaluated based on the haze signal obtained from at least the first sample W processed in the plasma etching device in the batch by the aforementioned signal processing device D (FIG. 12) (step S21). The haze signal used in the evaluation of the aging condition may be a haze signal obtained during defect inspection of the sample W, or a haze signal obtained by scanning the sample W under conditions where haze light is easily detected before or after defect inspection. Next, in the evaluation device 100, the haze signal obtained from the sample W is compared with the reference haze signal, and it is determined whether the difference between the two is within the reference range (step S22). The detailed example of the aging condition evaluation by the evaluation device 100 in steps S21 and S22 will be described later.

若在步驟S22中藉由評估裝置100判定出差分為基準範圍時，推定第1片試料W處理時的腔室為所希望的狀況，亦即老化處理為必要且充分。此時，由評估裝置100透過監視器E3通知該要旨而結束圖14的流程。例如若在製造線執行圖14的流程，若未感測老化條件的不完備，即直接繼續製造線的運轉狀態。但是，若在圖13的步驟S100中執行圖14的流程，由於有留下比其他更好的老化條件的候補的可能性，因此之後針對未試行的老化條件實施圖14的流程。If the difference is determined to be within the reference range by the evaluation device 100 in step S22, it is presumed that the chamber is in the desired state when the first sample W is processed, that is, the aging treatment is necessary and sufficient. At this time, the evaluation device 100 notifies this through the monitor E3 and ends the process of Figure 14. For example, if the process of Figure 14 is executed in the manufacturing line, if the incompleteness of the aging condition is not detected, the operation state of the manufacturing line is directly continued. However, if the process of Figure 14 is executed in step S100 of Figure 13, since there is a possibility that a candidate for a better aging condition than others is left, the process of Figure 14 is implemented for the aging condition that has not been tried.

若在步驟S22中，差分在基準範圍外時，推定第1片試料W處理時的腔室非為所希望的狀況，亦即老化處理不充分，由評估裝置100對監視器E3輸出警報(步驟S30)。If the difference is outside the reference range in step S22, it is estimated that the chamber condition during the processing of the first sample W is not the desired condition, that is, the aging treatment is insufficient, and the evaluation device 100 outputs an alarm to the monitor E3 (step S30).

確認到警報的操作人員等係針對有關該警報的老化條件，採取按照場面的對應(步驟S40)。按照場面的對應係指例如若為圖13的步驟S200、S300、S600的工程，為有不完備的老化條件的調整，若為步驟S100的工程，則將有不完備的老化條件由候補除外。若在製造線執行圖14的流程，在步驟S40中，必須依情況使電漿蝕刻裝置停止。老化條件的調整係依情況而需要製程裝置的狀況的變動要因的分析等。在製程裝置的狀況的變動要因的分析中，係進行例如將發生在試料W的不良部位以FIB (Focused Ion Beam，聚焦離子束)切取而以TEM(Transmission Electron Microscope，透射電子顯微鏡)進行觀察等。The operator who has confirmed the alarm takes corresponding actions according to the scene for the aging condition related to the alarm (step S40). The corresponding actions according to the scene refer to, for example, adjusting the incomplete aging conditions in the process of steps S200, S300, and S600 of FIG. 13, and removing the incomplete aging conditions from the reserve in the process of step S100. If the process of FIG. 14 is executed in the manufacturing line, the plasma etching device must be stopped in step S40 according to the situation. The adjustment of the aging conditions requires the analysis of the factors of change of the state of the process device according to the situation. In the analysis of the factors of variation in the condition of the process device, for example, a defective portion of the sample W is cut out with FIB (Focused Ion Beam) and observed with TEM (Transmission Electron Microscope).

-習知例- 在此，在圖14中與本實施例之以上的老化條件的評估工程一併以虛線顯示以一般製程裝置所處理的試料的完成結果的評估工程。以典型例而言，步驟S10的工程之後，以電漿蝕刻裝置所處理的批次的第1片及第N片試料W係例如藉由OCD對CD值以取樣測定1~數片(步驟S26)。此外，例如以橢圓偏振光譜儀等以取樣亦測定1~數片晶圓表面的蝕刻率(表面膜厚)(步驟S28)。CD值、蝕刻率的測定的順序係可任意變更。接著，判定最初測定到的第1片與第N片試料W的CD值或蝕刻率的差是否在基準範圍內(步驟S27、S29)。若測定結果的差不在基準範圍，懷疑第1片試料W處理時的腔室非為所希望的狀況，順序移至步驟S30。若檢查結果的差為基準範圍內，推定第1片試料W處理時的腔室為所希望的狀況，圖14的流程即結束。其中，如前所述，任何測定裝置亦非定常性測定批次內全試料，大多為取樣測定的情形，因此最初測定的第1片並不一定為在該批次中最初在製程裝置被處理的試料。 -Known Example- Here, in FIG. 14, the evaluation process of the completion result of the sample processed by the general process device is shown with a dotted line together with the evaluation process of the aging condition above in the present embodiment. For a typical example, after the process of step S10, the 1st and Nth samples W of the batch processed by the plasma etching device are sampled and measured for CD values by, for example, OCD (step S26). In addition, the etching rate (surface film thickness) of the surface of 1 to several wafers is also measured by sampling, for example, using an elliptical polarization spectrometer (step S28). The order of measuring CD value and etching rate can be changed arbitrarily. Next, determine whether the difference in CD value or etching rate between the first and Nth samples W is within the reference range (steps S27, S29). If the difference in the measurement results is not within the reference range, it is suspected that the chamber when processing the first sample W is not in the desired state, and the sequence moves to step S30. If the difference in the inspection results is within the reference range, it is inferred that the chamber when processing the first sample W is in the desired state, and the process of Figure 14 ends. Among them, as mentioned above, any measuring device does not measure all samples in the batch in a steady state, and most of them are sampling measurements. Therefore, the first piece measured initially is not necessarily the first sample processed in the process device in the batch.

此外，在步驟S26的CD測定中，由於測定對象為CD，因此無法藉由未形成有圖案的試料W來評估老化條件。因此，為了在研究開發線評估且決定老化條件，為了測定，必須準備附圖案的晶圓，耗費成本。此外，CD值的測定係僅針對試料W的一部分區域進行，無法沒有遺漏地確認試料W的全面的處理狀態，亦有無法感測老化條件不完備的情形。In addition, in the CD measurement of step S26, since the measurement object is CD, the aging condition cannot be evaluated by the sample W without a pattern. Therefore, in order to evaluate and determine the aging condition in the research and development line, a wafer with a pattern must be prepared for the measurement, which is costly. In addition, the CD value is measured only for a part of the sample W, and the overall processing status of the sample W cannot be confirmed without omission, and there is also a possibility that the aging condition is not complete.

以測定CD值的裝置而言，除了OCD之外，亦有使用CD-SEM(Critical Dimension-Scanning Electron Microscope)的情形。但是，使用CD-SEM時，亦衍生與使用OCD時相同的課題。In addition to OCD, CD-SEM (Critical Dimension-Scanning Electron Microscope) is also used to measure CD values. However, the same issues arise when using CD-SEM as when using OCD.

此外，步驟S28的蝕刻率的測定並不需要在試料W形成有圖案，但是與CD值的測定相同，因僅針對試料W的一部分區域進行，測定部位為局部性，有在不完備的感測發生遺漏的可能性。The etching rate measurement in step S28 does not require a pattern to be formed on the sample W, but like the CD value measurement, it is performed only on a part of the sample W, and the measurement site is local, so there is a possibility of omission due to incomplete sensing.

以上的CD值或蝕刻率係與試料W的形狀(處理狀態)的相關高，相對較容易測定，因此在半導體的製造工程等中，在評估中主要測定製程裝置的老化條件。但是，除了CD值或蝕刻率的檢查之外，亦被利用在老化條件的評估的檢查係自以往即存在。例如，藉由TEM所為之缺陷觀察。The CD value or etching rate mentioned above is highly correlated with the shape (processing state) of the sample W and is relatively easy to measure. Therefore, in semiconductor manufacturing engineering, the aging conditions of the process equipment are mainly measured in the evaluation. However, in addition to the inspection of the CD value or etching rate, inspections that are also used in the evaluation of aging conditions have existed since ancient times. For example, defect observation by TEM.

TEM係可仔細觀察在試料W所產生的缺陷，因此對老化條件的分析為有效。可仔細觀察的另一面，與OCD或CD-SEM相比，測定所花時間非常耗時。此外，TEM一般而言被稱為破壞檢查，必須將用以利用TEM進行觀察的試驗片以例如FIB等由晶圓切出，一部分被切取的晶圓係失去製品價值，無法再度送回至製造線。此外，必須由製造線將試料W帶出至FIB裝置等、或將所切出的試料片由FIB裝置搬送至TEM，若僅為了評估老化條件而使用TEM，耗費所需以上更多精力及時間。此外，以TEM所觀察的試驗片係試料W的微小一部分，因此老化條件的評估精度係大幅影響試驗片的摘出部位。TEM can carefully observe the defects generated in the sample W, so it is effective for analyzing the aging conditions. On the other hand, compared with OCD or CD-SEM, the time spent on measurement is very time-consuming. In addition, TEM is generally called destructive inspection, and the test piece used for observation with TEM must be cut out from the wafer by, for example, FIB, and a part of the cut wafer loses the product value and cannot be sent back to the manufacturing line. In addition, the sample W must be taken out from the manufacturing line to the FIB device, or the cut sample piece must be transported from the FIB device to the TEM. If TEM is used only to evaluate the aging conditions, it will take more energy and time than necessary. In addition, the test piece observed by TEM is a tiny part of the sample W, so the evaluation accuracy of the aging conditions greatly affects the removal location of the test piece.

此外，在製程裝置係有可藉由OES(Optical Emission Spectrometer)或溫度感測器，採用處理中的腔室內的狀態作為資料者。藉由OES，可監視腔室內的電漿發光狀態。此外，可藉由溫度感測器來測定處理中的試料W或腔室內的溫度。但是，OES雖可觀察電漿發光狀態，但是並無法將腔室的空間全體的狀態區分為微細區域而按每個區域監視狀態。此外，藉由溫度感測器所為之試料W的溫度測定亦為局部性。因此，在以電漿蝕刻裝置所取得的該等資料中，以用以驗證試料W的處理狀態與老化條件的相關的資料而言，粗略而無法謂為充分乃為實際情形。In addition, the process equipment can use the state of the chamber being processed as data through OES (Optical Emission Spectrometer) or temperature sensor. The plasma luminescence state in the chamber can be monitored by OES. In addition, the temperature of the sample W being processed or in the chamber can be measured by a temperature sensor. However, although OES can observe the plasma luminescence state, it cannot divide the state of the entire space of the chamber into micro areas and monitor the state of each area. In addition, the temperature measurement of the sample W by the temperature sensor is also local. Therefore, among the data obtained by the plasma etching device, the data related to the processing state and aging conditions of the sample W are rough and cannot be called sufficient, which is the actual situation.

-因老化條件不完備所致之對試料的影響- 圖15係表示製程裝置的腔室的溫度的歷時變化的模式圖，圖16係表示伴隨製程裝置的腔室的溫度的歷時變化而在晶圓所出現的影響的模式圖。圖15的橫軸表示時間、縱軸表示腔室內的溫度。在此亦列舉電漿蝕刻裝置作為製程裝置的具體例來作說明。其中，為方便起見，將在圖15及圖16之例中所處理的試料W的批次記載為「批次F」。 - Impact on samples due to incomplete aging conditions- Figure 15 is a schematic diagram showing the temporal change of the temperature of the chamber of the process device, and Figure 16 is a schematic diagram showing the impact on the wafer caused by the temporal change of the temperature of the chamber of the process device. The horizontal axis of Figure 15 represents time, and the vertical axis represents the temperature in the chamber. A plasma etching device is also cited as a specific example of a process device for explanation. For convenience, the batch of sample W processed in the examples of Figures 15 and 16 is recorded as "Batch F".

若電漿蝕刻裝置的待機(閒置(idling))狀態持續，腔室冷卻，腔室的溫度係低於若在被設定的製程條件下進行電漿蝕刻處理即可良好處理試料W的安定溫度。若持續了超過一定時間的待機狀態之後處理試料W的批次F時，在進行批次F的第1片的處理之前在電漿蝕刻裝置中進行校正放電等老化處理。但是，如圖15所示，電漿蝕刻處理後，若在腔室的溫度未上昇至安定溫度之前即開始第1片試料W的處理，有在第1片試料W處理時，腔室未成為所希望的狀況的情形。If the standby (idling) state of the plasma etching device continues, the chamber cools down, and the temperature of the chamber is lower than the stable temperature at which the sample W can be well processed if the plasma etching process is performed under the set process conditions. If the batch F of the sample W is processed after the standby state continues for more than a certain period of time, the plasma etching device is subjected to aging treatment such as calibration discharge before the first piece of the batch F is processed. However, as shown in FIG15, after the plasma etching process, if the processing of the first sample W is started before the temperature of the chamber rises to the stable temperature, there is a case where the chamber does not become the desired state when the first sample W is processed.

如前述，電漿蝕刻裝置中的狀況的變化係表現在試料W的處理狀態。在圖16中表示針對在如圖15所示之溫度環境下經電漿蝕刻處理之第1片、第2片、…第N片試料W，由評估裝置100所得的霧度圖(試料面上的霧度分布)之例。在圖15及圖16之例中，設為第2片之後的試料W處理時，腔室的溫度到達安定溫度，且亦包含腔室內的氣體的充滿度等而腔室的狀況整頓者。此時，如圖16所例示，在未滿安定溫度的狀態下被處理的第1片試料W，與在之後達至安定溫度的狀態下被處理的第2片之後的試料W相比較，在例如邊緣(外緣部)X1或局部X2等任意部位出現霧度訊號的強度差。As mentioned above, the change of the state in the plasma etching device is reflected in the processing state of the sample W. FIG16 shows an example of the haze diagram (haze distribution on the sample surface) obtained by the evaluation device 100 for the first, second, ... Nth sample W processed by plasma etching in the temperature environment shown in FIG15. In the examples of FIG15 and FIG16, it is assumed that when the second and subsequent samples W are processed, the temperature of the chamber reaches a stable temperature, and the state of the chamber including the fullness of the gas in the chamber is regulated. At this time, as shown in Figure 16, the first sample W processed before the stable temperature is reached has a difference in the intensity of the fog signal at any location such as the edge (outer edge) X1 or the local X2, compared with the second and subsequent samples W processed after the stable temperature is reached.

在本實施例中，根據藉由評估裝置100掃描批次F的第1片試料W所取得的霧度訊號，如前所述藉由訊號處理裝置D，評估在電漿蝕刻裝置中適用於批次F的老化處理的老化條件。In this embodiment, based on the haze signal obtained by scanning the first sample W of the batch F by the evaluation device 100, the aging conditions applied to the aging treatment of the batch F in the plasma etching device are evaluated by the signal processing device D as described above.

其中，作為習知例而之前所說明之藉由OCD等所為之CD測定、藉由橢圓偏振光譜儀等所為之蝕刻率的測定、藉由OES所為之電漿狀態的監視、藉由TEM所為之試料的局部詳細觀察等均可與藉由霧度光所為之檢查並存。採取與該等測定合作，可進行藉由霧度光所為之老化條件的評估，自不待言。Among them, as a known example, CD measurement by OCD, etc., measurement of etching rate by elliptical polarization spectrometer, etc., monitoring of plasma state by OES, and local detailed observation of samples by TEM can all be performed in conjunction with inspection by haze light. It goes without saying that evaluation of aging conditions by haze light can be performed in conjunction with these measurements.

-老化條件評估的詳細順序- 圖17係表示藉由本實施例之評估裝置100所為之老化條件的評估處理的順序的流程圖。同圖的處理係在圖14的流程圖的步驟S21、S22中執行。在此，例示使用在圖15的說明中所使用的批次F(試料W的片數N)來評估老化條件的情形。此外，在以下說明中列舉在圖17的流程開始時點，批次F的掃描完成，至少針對第1片與第N片試料W，霧度訊號被儲存在記憶裝置DB(圖1)的情形為例。接著，列舉將在第N片試料W所得的霧度訊號設為基準霧度訊號時為例來作說明。但是，亦可形成為若在第1片試料W的掃描時點既已存在基準霧度訊號時，與第1片試料W的掃描並行來執行圖17的流程的構成。此時，後述步驟S202的順序係成為迴圈的最初順序。 -Detailed sequence of aging condition evaluation- FIG. 17 is a flowchart showing the sequence of aging condition evaluation processing performed by the evaluation device 100 of the present embodiment. The processing of the same figure is executed in steps S21 and S22 of the flowchart of FIG. 14. Here, the case of evaluating aging conditions using batch F (N number of samples W) used in the description of FIG. 15 is exemplified. In addition, in the following description, the case where the scanning of batch F is completed at the start point of the process of FIG. 17, and the haze signal is stored in the memory device DB (FIG. 1) for at least the 1st and Nth samples W is taken as an example. Next, the case where the haze signal obtained from the Nth sample W is set as the reference haze signal is taken as an example for explanation. However, if the reference fog signal already exists at the time of scanning the first sample W, the process of FIG. 17 may be executed in parallel with the scanning of the first sample W. In this case, the sequence of step S202 described later becomes the initial sequence of the loop.

若開始圖17的流程，評估裝置100的訊號處理裝置D係由記憶裝置DB讀入基準霧度訊號，亦即在第N片試料W所得的霧度訊號(步驟S201)。此外，訊號處理裝置D係由記憶裝置DB讀入在第1片試料W所得的霧度訊號(步驟S202)。步驟S201、S202的順序亦可相反。When the process of FIG. 17 is started, the signal processing device D of the evaluation device 100 reads the reference haze signal from the memory device DB, that is, the haze signal obtained from the Nth sample W (step S201). In addition, the signal processing device D reads the haze signal obtained from the first sample W from the memory device DB (step S202). The order of steps S201 and S202 may also be reversed.

接著，訊號處理裝置D係針對試料W的任意區域，將在第1片試料W所得的霧度訊號與基準霧度作比較(步驟S203)，判定兩者的差分是否為預先設定的設定值以內(步驟S204)。任意區域亦可為試料W的全面，亦可僅限定於試料W內的特定的區域。或者，亦可將試料W分為複數區域，按每個區域依序進行。訊號處理裝置D係若霧度訊號與基準霧度的差分為設定值以內，將該區域記錄為在霧度訊號與基準霧度之間無顯著性差異的(差分為設定值以內的)均等區域(步驟S205)。相反地，訊號處理裝置D係若霧度訊號與基準霧度的差分超過設定值，將該區域記錄為在霧度訊號與基準霧度之間有顯著性差異的(差分超過設定值的)差分區域(步驟S206)。在該例中係將基準試料設為第N片試料W，因此並不一定為全面正常的處理狀態，惟若假定第N片試料W全面正常形成，差分區域係發生某些異常的可能性高的區域。Next, the signal processing device D compares the haze signal obtained from the first sample W with the reference haze for any area of the sample W (step S203), and determines whether the difference between the two is within a preset setting value (step S204). The arbitrary area may be the entire sample W, or may be limited to a specific area within the sample W. Alternatively, the sample W may be divided into a plurality of areas, and the process may be performed sequentially for each area. If the difference between the haze signal and the reference haze is within a setting value, the signal processing device D records the area as an equal area with no significant difference (the difference is within the setting value) between the haze signal and the reference haze (step S205). On the contrary, if the difference between the haze signal and the reference haze exceeds the set value, the signal processing device D records the area as a difference area where there is a significant difference between the haze signal and the reference haze (the difference exceeds the set value) (step S206). In this example, the reference sample is set to the Nth sample W, so it is not necessarily a completely normal processing state. However, if it is assumed that the Nth sample W is formed completely normally, the difference area is an area with a high possibility of some abnormality.

訊號處理裝置D係若將試料W分為複數區域來進行時，按每個區域反覆步驟S203-S206的處理，針對試料W的全區域一執行處理，即判定評估結果是否在基準範圍內，具體而言差分區域數是否為預先設定的容許值以下(步驟S207)。If the signal processing device D divides the sample W into multiple regions, it repeats steps S203-S206 for each region, and once the processing is performed on the entire region of the sample W, it determines whether the evaluation result is within the reference range, specifically whether the number of differential regions is below a preset allowable value (step S207).

訊號處理裝置D係若在試料W全面與基準霧度的差分為設定值以下、或差分區域數為容許值以下，推定在作為批次F的前處理所進行的老化處理的老化條件並無問題。此時，訊號處理裝置D係生成表示在老化條件製程裝置無問題的資料，例如記錄在記憶裝置DB，並且透過控制裝置E1而顯示在監視器E3而結束順序(步驟S208)。相反地，若與基準霧度的差分超過設定值、或差分區域數超過容許值時，懷疑老化條件不完備。此時，訊號處理裝置D係生成表示懷疑作為批次F的前處理所進行的老化處理不完備的警報資料，例如記錄在記憶裝置DB，並且輸出至監視器E3而結束順序(步驟S209)。If the difference between the whole sample W and the reference mist is less than the set value or the number of difference zones is less than the allowable value, the signal processing device D presumes that there is no problem with the aging condition of the aging treatment performed as the pre-treatment of the batch F. At this time, the signal processing device D generates data indicating that there is no problem with the process device under the aging condition, for example, records it in the memory device DB, and displays it on the monitor E3 through the control device E1 to end the sequence (step S208). On the contrary, if the difference from the reference mist exceeds the set value or the number of difference zones exceeds the allowable value, it is suspected that the aging condition is not complete. At this time, the signal processing device D generates alarm data indicating that the aging process performed as a pre-processing of the batch F is suspected to be incomplete, for example, records it in the memory device DB, and outputs it to the monitor E3 to end the sequence (step S209).

亦可為例如生成有關第1片試料W的霧度圖與基準霧度訊號的霧度圖的差分畫像，且將該等作比較的演算法。此外，亦可採用在試料W與基準霧度訊號的霧度圖的差分畫像上對差分區域數進行計數的演算法。For example, an algorithm may be used to generate a difference image between the haze map of the first sample W and the haze map of the reference haze signal and compare them. In addition, an algorithm may be used to count the number of difference areas on the difference image between the haze map of the sample W and the reference haze signal.

此外，亦可在判定基準加上霧度圖的分布。例如，亦可適用將試料W的表面分為圓形的中央部及包圍其的環狀的外周部，著重在中央部與外周部之中的特定的部分，例如外周部的霧度訊號的變化，若在外周部有一定以上的變化時即推定為在老化條件有某些不完備的演算法。此外，亦可考慮將在中央部及外周部的雙方有一定以上的霧度訊號的變化作為判定條件、或將僅在中央部或僅在外周部有一定以上的霧度訊號的變化作為判定條件。In addition, the distribution of the haze diagram can also be added to the judgment criteria. For example, it is also possible to divide the surface of the sample W into a circular central part and a ring-shaped peripheral part surrounding it, and focus on a specific part between the central part and the peripheral part, such as the change of the haze signal in the peripheral part. If there is a certain change in the peripheral part, it is inferred that there are some incomplete algorithms under the aging conditions. In addition, it is also possible to consider using the change of the haze signal in both the central part and the peripheral part as a judgment condition, or using the change of the haze signal in only the central part or only the peripheral part as a judgment condition.

此外，步驟S208、S209對監視器E3的輸出亦可為未透過監視器的輸出。此外，輸出形式係除了藉由聲音或本文(text)所得之訊息之外，亦可一併顯示針對試料W的霧度圖。例如，若輸出至監視器E3，亦可將出現在試料W的特性變化(例如表面的表面粗糙度變化、表面膜厚變化)的資料作為附加資訊而連同警報一起輸出。In addition, the output of steps S208 and S209 to the monitor E3 may also be output without passing through the monitor. In addition, the output form is not only the information obtained by sound or text, but also the haze diagram for the sample W can be displayed at the same time. For example, if the output is to the monitor E3, the data of the characteristic change of the sample W (such as the surface roughness change, the surface film thickness change) can also be output together with the alarm as additional information.

-效果- (1)在本實施例中，光學式掃描被處理為在製程裝置中伴隨老化處理被處理的1批次的第1片的試料W，將由該試料W所得的霧度訊號分別與基準霧度訊號作比較來評估老化條件。在亦為試料W的缺陷檢查裝置的評估裝置100中，可評估缺陷以外的老化條件。相較於被使用在用以符合老化條件的詳細觀察的TEM，可遠遠高速取得結果，因此可大幅短縮老化條件評估所需時間。若在評估裝置100中以缺陷檢查的掃描條件取得在老化條件的評估中為充分的霧度訊號，亦不需要在評估裝置100中有別於缺陷檢查而另外以老化條件評估目的另外掃描試料W，可期待更進一步的時間短縮效果。 -Effects- (1) In this embodiment, optical scanning is performed on the first sample W of a batch that is processed in a process device along with an aging process, and the haze signal obtained from the sample W is compared with the reference haze signal to evaluate the aging condition. In the evaluation device 100, which is also a defect inspection device for the sample W, aging conditions other than defects can be evaluated. Compared with a TEM used for detailed observation of aging conditions, the results can be obtained at a much higher speed, so the time required for aging condition evaluation can be greatly shortened. If a sufficient haze signal is obtained in the evaluation device 100 under the scanning conditions for defect inspection in the evaluation device 100 for the evaluation of aging conditions, there is no need to scan the sample W separately for the purpose of aging condition evaluation in the evaluation device 100 other than defect inspection, and further time reduction effect can be expected.

此外，可針對試料W的全面，沒有遺漏地檢查對應製程裝置的狀況的變動而在試料W出現的變化。尤其電漿蝕刻裝置等電漿處理裝置的狀況變動的影響係局部出現在試料W的面內，因此可沒有遺漏地檢查試料W的全面，藉此在抑制檢查遺漏的觀點中可針對老化條件的評估確保高可靠性。此外，藉由使用試料W的全面的霧度訊號的分布，亦即霧度圖，可將藉由製程裝置所致之處理狀態、進而製程裝置的腔室內的狀況可視化。若為例如電漿處理裝置的情形，若可根據霧度圖，掌握氣體的濃淡或自由基密度等電漿氣相狀態，不限於老化條件，亦可達成製程條件的設定的平順化。與如OCD或橢圓偏振光譜儀般僅測定試料的取樣點的裝置相比，在此點具有優勢。Furthermore, the changes in the sample W that occur in response to changes in the status of the process device can be checked without omission for the entire sample W. In particular, the influence of changes in the status of plasma processing devices such as plasma etching devices is partially reflected in the surface of the sample W, so the entire sample W can be checked without omission, thereby ensuring high reliability for the evaluation of aging conditions while suppressing omissions in inspection. In addition, by using the distribution of the haze signal of the entire sample W, that is, the haze map, the processing status caused by the process device and the status in the chamber of the process device can be visualized. For example, in the case of a plasma processing device, if the gas concentration or radical density of the plasma gas phase can be understood based on the haze diagram, the setting of process conditions can be smoothed, not limited to aging conditions. Compared with devices such as OCD or elliptical polarization spectrometers that only measure the sampling point of the sample, this is an advantage.

此外，若在半導體的製造線適用藉由霧度光所為之老化條件的評估，藉由評估裝置100，可伴隨在線內天天進行的試料W的缺陷檢查而適時感測製程裝置的老化條件的不完備。根據該霧度光的老化條件的評估結果係可伴隨缺陷檢查而得，因此亦不會有對操作人員強使作業負擔或檢查成本增加的情形。利用天天進行的缺陷檢查而迅速地感測製程裝置的老化條件的不完備，因此亦抑制試料W的不良發生，亦抑制供作藉由TEM等所為之缺陷的原因解析的試料W的發生。此外，亦可假想防止試料W不良發生於未然或提升製程裝置的運轉率的效果，亦可期待成品率提升。Furthermore, if the evaluation of aging conditions by haze light is applied to the semiconductor manufacturing line, the evaluation device 100 can be used to timely detect the imperfection of the aging conditions of the process equipment along with the defect inspection of the sample W performed every day in the line. The evaluation result of the aging condition by haze light can be obtained along with the defect inspection, so there is no situation of forcing the operator to bear the work burden or increasing the inspection cost. By using the defect inspection performed every day to quickly detect the imperfection of the aging conditions of the process equipment, the occurrence of sample W defects is suppressed, and the occurrence of sample W for defect cause analysis by TEM, etc. is also suppressed. In addition, it is also possible to imagine the effect of preventing sample W defects from occurring before they occur or improving the operation rate of the process equipment, and it is also possible to expect an increase in the yield rate.

此外，與使用OCD或CD-SEM來計測CD值時不同，即使為未形成有圖案的試料W，亦可進行老化條件的評估。若為半導體的研究開發階段，若準備未形成有圖案的試料W(例如裸晶圓)作為評估用晶圓即足夠，因此無須僅為了評估而準備平均每1片的成本遠遠很高的形成有圖案的試料即可。此外，可未經由用以形成圖案的複數工程，因此可短期進行老化條件的決定。此外，由於不需要使用TEM時的破壞檢查，因此可刪減藉由FIB等所致之加工時間。由於為使用高速的光學式缺陷檢查裝置所進行的評估，因此原本的測定時間亦短。藉由根據霧度訊號來評估老化條件，亦可使藉由OCD或CD-SEM所為之CD測定或藉由TEM所為之檢查的頻度降低。Furthermore, unlike when the CD value is measured using OCD or CD-SEM, the aging condition can be evaluated even for a sample W that has not been patterned. In the research and development stage of semiconductors, it is sufficient to prepare a sample W that has not been patterned (e.g., a bare wafer) as an evaluation wafer, so there is no need to prepare a sample with a pattern, which has a much higher cost per wafer, just for the evaluation. In addition, since the multiple processes for forming the pattern are not required, the aging condition can be determined in a short time. In addition, since the destructive inspection when using TEM is not required, the processing time caused by FIB, etc. can be eliminated. Since the evaluation is performed using a high-speed optical defect inspection device, the original measurement time is also short. By evaluating the aging condition based on the haze signal, the frequency of CD measurements by OCD or CD-SEM or inspections by TEM can also be reduced.

(2)在評估裝置100中，複數檢測光學系統Bn相對射束點BS分別改變方向來作配置。藉此，可選擇有效於捕捉霧度光的強度變化的一或複數檢測光學系統Bn，且僅使用複數檢測光學系統Bn之中所選擇者來評估老化條件。若假設形成為與對霧度光的感度無關係而將複數檢測光學系統Bn的訊號合併輸出的構成時，以特定的檢測光學系統Bn被高感度檢測的變化被稀釋而反而檢查感度降低。相對於此，在本實施例中，可活用具有方向不同的複數檢測光學系統Bn的構成來高感度地進行老化條件評估。(2) In the evaluation device 100, the plurality of detection optical systems Bn are configured to change their directions relative to the beam spot BS. In this way, one or more detection optical systems Bn that are effective in capturing intensity changes of haze light can be selected, and only the selected one among the plurality of detection optical systems Bn is used to evaluate the aging condition. If a configuration is assumed in which the signals of the plurality of detection optical systems Bn are combined and outputted regardless of the sensitivity to haze light, the changes detected with high sensitivity by a specific detection optical system Bn are diluted, and the detection sensitivity is reduced. In contrast, in this embodiment, the configuration of the plurality of detection optical systems Bn with different directions can be utilized to perform aging condition evaluation with high sensitivity.

在本實施例中，尤其可針對檢測光學系統Bn，分別將霧度訊號與其變動要因的相關記憶在記憶裝置DB，根據該相關，將特定的方位角ϕ1的檢測光學系統Bn選擇性地使用在老化條件評估。藉此，可按照試料表面的表面膜厚或表面粗糙度等霧度光強度的變動要因來評估老化條件。在本實施例中係說明由入射至相對射束點BS位於照明光的正反射方向的開口α3、α4的霧度訊號與其基準霧度訊號的差分，來感測有關試料W的表面粗糙度的預定範圍的變化的製程裝置的狀況變動之例。此外，亦說明了由入射至相對射束點BS位於與照明光的正反射方向為相反方向的開口α1、α6的霧度訊號與其基準霧度訊號的差分，來感測有關試料W的表面膜厚的預定範圍的變化的製程裝置的狀況變動之例。In this embodiment, the correlation between the haze signal and its variation factor can be stored in the memory device DB for the detection optical system Bn, and based on the correlation, the detection optical system Bn of a specific azimuth angle φ1 can be selectively used in the aging condition evaluation. In this way, the aging condition can be evaluated according to the variation factor of the haze light intensity such as the surface film thickness or surface roughness of the sample surface. In this embodiment, an example of sensing the state change of the process device related to the variation of the surface roughness of the sample W within a predetermined range by the difference between the haze signal of the openings α3 and α4 incident on the relative beam point BS in the regular reflection direction of the illumination light and its reference haze signal is described. In addition, an example is described of sensing the change in the state of a process device related to the change within a predetermined range of the surface film thickness of the sample W by the difference between the haze signal of the openings α1 and α6 incident on the relative beam point BS in the opposite direction to the regular reflection direction of the illumination light and its reference haze signal.

此外，若為本實施例，檢測光學系統Bn係可以偏光分光器Bc將霧度光按照偏光方向進行分離，且針對由試料W上的同一座標朝同一方向出射的霧度光，檢測偏光方向不同的2個光。藉由該構成，按每個檢測光學系統Bn，亦即按每個霧度光的出射方向，根據針對霧度訊號的強度、偏光方向、及霧度訊號的變動要因所規定的相關資料，可執行在參數亦包含有霧度光的偏光方向的更精彩的老化條件評估。Furthermore, in this embodiment, the detection optical system Bn can separate the haze light according to the polarization direction by the polarization beam splitter Bc, and detect two lights with different polarization directions for the haze light emitted in the same direction from the same coordinate on the sample W. With this configuration, according to the relevant data specified for the intensity, polarization direction, and change factor of the haze signal, for each detection optical system Bn, that is, for each emission direction of the haze light, a more sophisticated aging condition evaluation can be performed in which the parameter also includes the polarization direction of the haze light.

(第2實施例) 在第1實施例中係說明了將試料W的各區域的霧度訊號與基準霧度訊號作比較來評估老化條件之例。在半導體製造線中，如上所示關於天天執行的評估，若蓄積資料來進行機械學習，亦可根據學習完畢模型，來評估老化條件。 (Second embodiment) In the first embodiment, an example of evaluating aging conditions by comparing the mist signal of each area of the sample W with the reference mist signal was described. In a semiconductor manufacturing line, if the evaluation is performed daily as shown above and data is accumulated for machine learning, the aging conditions can also be evaluated based on the learned model.

學習完畢模型係藉由學習用資料的機械學習被組入學習完畢參數的推論程式，對關於所被輸入的霧度訊號的資料輸出老化條件的評估結果。該學習完畢模型係在訊號處理裝置D或控制裝置E1中作成，且被儲存在例如記憶裝置DB。訊號處理裝置D係使用該學習完畢模型，根據伴隨老化處理被處理的試料W的缺陷檢查時所取得的霧度訊號，來評估老化條件。The learned model is an inference program of a learned parameter incorporated by mechanical learning of learning data, and outputs an evaluation result of the aging condition for data related to the inputted mist signal. The learned model is created in the signal processing device D or the control device E1 and stored in, for example, the memory device DB. The signal processing device D uses the learned model to evaluate the aging condition based on the mist signal obtained during the defect inspection of the sample W processed with the aging treatment.

學習用資料之一例係試料W的霧度圖、霧度光的偏光方向、製程裝置的待機時間、老化條件的評估結果、老化條件的調整履歷、評估結果的好壞等天天在半導體製造製程所蓄積的實績資料。製程裝置的待機時間係藉由例如由製程裝置收訊、或操作人員等的輸入等，在記憶裝置DB蓄積資料。老化條件的調整履歷或評估結果的好壞等係一種回饋資料，例如可按照預先備妥的輸入畫面，藉由輸入裝置E2來輸入調整了老化條件者。評估結果的好壞係指例如調整了老化條件者的判斷，由評估裝置100被通知的警報是否為真的通知老化條件不完備者等事項。One example of learning data is the haze diagram of sample W, the polarization direction of haze light, the standby time of the process equipment, the evaluation results of the aging conditions, the adjustment history of the aging conditions, the quality of the evaluation results, and other performance data accumulated every day in the semiconductor manufacturing process. The standby time of the process equipment is data accumulated in the memory device DB by, for example, receiving a signal from the process equipment or input from an operator. The adjustment history of the aging conditions or the quality of the evaluation results is a kind of feedback data, and for example, the person who adjusted the aging conditions can be input through the input device E2 according to a pre-prepared input screen. The quality of the evaluation results refers to, for example, the judgment of the person who adjusted the aging conditions, whether the alarm notified by the evaluation device 100 is true, and whether the person who notified the aging conditions is incomplete.

圖18係機械學習的概念圖。在此係說明在訊號處理裝置D中執行機械學習而生成學習完畢模型之例。訊號處理裝置D係檢索前述試料W的霧度圖、製程裝置的待機時間、老化條件的評估結果或調整履歷等實績資料而由記憶裝置DB讀入，且生成學習用資料。訊號處理裝置D係使神經網路D9讀入該學習用資料，且使輸入層、中間層、輸出層的神經元彼此的相連的加權最適化。藉此，由散射方向、光強度、偏光方向、座標等針對試料W所得的霧度訊號的資料，生成評估老化條件的學習完畢模型。其中，學習完畢模型亦可由其他電腦所生成，而非侷限於訊號處理裝置D。FIG18 is a conceptual diagram of mechanical learning. Here, an example of executing mechanical learning in a signal processing device D to generate a learned model is described. The signal processing device D retrieves the haze map of the sample W, the standby time of the process device, the evaluation results of the aging conditions, or the adjustment history and other performance data from the memory device DB, and generates learning data. The signal processing device D causes the neural network D9 to read the learning data, and optimizes the weighted connections between the neurons of the input layer, the intermediate layer, and the output layer. In this way, a learned model for evaluating the aging conditions is generated based on the data of the haze signal obtained for the sample W, such as the scattering direction, light intensity, polarization direction, and coordinates. The learned model can also be generated by other computers, rather than being limited to the signal processing device D.

此外，亦考慮可藉由訊號處理裝置D或控制裝置E1，將霧度圖與老化條件的調整履歷作為輸入來進行機械學習，且按每個老化條件的參數，特定與霧度圖的相關且提示老化條件的調整案。In addition, it is also considered that the signal processing device D or the control device E1 can use the adjustment history of the haze map and the aging condition as input to perform mechanical learning, and according to the parameters of each aging condition, the correlation with the haze map is specific and the adjustment plan of the aging condition is prompted.

關於其他點，本實施例係與第1實施例相同。在本實施例中，係伴隨根據霧度訊號及基準霧度訊號的差的比較的評估資料的蓄積，生成亦加上老化條件的調整履歷或評估結果的好壞等回饋資料的學習完畢模型，可期待老化條件的評估精度的提升。此外，如上所述在需要調整老化條件的場面中，藉由利用評估裝置100所得之調整案，亦可期待操作人員的條件調整的支援。In other respects, this embodiment is the same as the first embodiment. In this embodiment, a learning model is generated that also includes feedback data such as the adjustment history of the aging condition or the quality of the evaluation result, along with the accumulation of evaluation data based on the comparison of the difference between the fog signal and the reference fog signal, so that the evaluation accuracy of the aging condition can be expected to be improved. In addition, in the scene where the aging condition needs to be adjusted as described above, by using the adjustment plan obtained by the evaluation device 100, it can also be expected that the operator can be supported in adjusting the condition.

(第3實施例) 圖19係將本發明之一變形例之老化條件評估裝置的主要部分抽出的模式圖。對於圖19中與在第1實施例及第2實施例中所說明的要素相同或對應的要素，標註與前述圖面相同符號且省略說明。 (Third embodiment) FIG. 19 is a schematic diagram showing the main parts of an aging condition evaluation device according to a variation of the present invention. Elements in FIG. 19 that are the same as or correspond to those described in the first and second embodiments are marked with the same symbols as those in the aforementioned drawings and their description is omitted.

本實施例係在前述基準霧度訊號(第1實施例)或學習完畢模型(第2實施例)的基礎資料，包含在複數評估裝置所得的資料之例。在本實施例中，評估裝置100係適當透過網路(未圖示)而連接於資料伺服器DS。在該資料伺服器DS係適當透過網路，連接有與評估裝置100不同的其他評估裝置100’、100”。 評估裝置100、100’、100”係以同一種類或同等種類(同一系列、同一製造商等)為宜，亦可為不同種類的裝置。在圖19中係圖示2個其他評估裝置100’、100”，惟連接於資料伺服器DS的其他評估裝置可為1個，亦可為3個以上。The present embodiment is an example in which the basic data of the aforementioned reference haze signal (first embodiment) or the learned model (second embodiment) includes data obtained from a plurality of evaluation devices. In the present embodiment, the evaluation device 100 is appropriately connected to the data server DS via a network (not shown). The data server DS is appropriately connected via a network to other evaluation devices 100', 100". The evaluation devices 100, 100', 100" are preferably of the same type or equivalent type (same series, same manufacturer, etc.), but may also be different types of devices. FIG. 19 illustrates two other evaluation devices 100', 100", but the number of other evaluation devices connected to the data server DS may be one, or may be three or more.

在資料伺服器DS，由評估裝置100、100’、100”被輸入評估資料等，且蓄積該等資料。在該蓄積資料，除了例如按每個評估裝置的包含霧度訊號或評估結果等的老化條件的評估資料之外，可包含試料W的設計資料、老化條件的調整履歷、評估結果的好壞、試料W的檢查資料等。此外，關於試料W的缺陷檢查，亦可使檢查條件(檢查配方(recipe))、缺陷覆核(review)資料、缺陷材料分析資料等，一併蓄積在資料伺服器DS。缺陷材料分析資料係指有例如在能量分散型X線分析所得的資訊。此亦有為獨立型的裝置的情形，惟亦有裝載在缺陷覆核裝置的情形，亦可在連同缺陷覆核資訊一起取得時一併取得。在資料伺服器DS中，根據如此之蓄積資料，關於老化條件的評估，運算基準霧度訊號或學習完畢模型。基準霧度訊號或學習完畢模型的運算亦可在資料伺服器DS中，每隔一定期間執行，亦可新資料一蓄積一定以上即被執行。各評估裝置100、100’、100”係在老化條件的評估的機會中，由資料伺服器DS收訊最新的基準霧度訊號或學習完畢模型來執行老化條件的評估。Evaluation data and the like are inputted from the evaluation devices 100, 100', 100" and stored in the data server DS. The stored data may include, in addition to evaluation data of aging conditions such as fog signals or evaluation results for each evaluation device, design data of the sample W, adjustment history of aging conditions, quality of evaluation results, inspection data of the sample W, and the like. In addition, regarding defect inspection of the sample W, inspection conditions (inspection recipes), defect review data, defect material analysis data, and the like may also be stored in the data server DS. Defect material analysis data refers to, for example, information obtained by energy dispersive X-ray analysis. The information obtained. This may be a stand-alone device, but it may also be installed in a defect review device, and it may be obtained together with the defect review information. In the data server DS, based on the accumulated data, the benchmark fog signal or the learned model is calculated for the evaluation of the aging condition. The calculation of the benchmark fog signal or the learned model may also be executed in the data server DS at regular intervals, or it may be executed as soon as new data is accumulated above a certain amount. Each evaluation device 100, 100', 100" receives the latest benchmark fog signal or learned model from the data server DS during the opportunity of evaluating the aging condition to perform the evaluation of the aging condition.

藉由本實施例，除了評估裝置100的自己的資料之外，將藉由其他評估裝置100、100’所得之多數資料作為基礎資料，來運算基準霧度訊號或學習完畢模型。因此，短期蓄積更多的基礎資料，且可歷時地提升老化條件的評估精度。In this embodiment, in addition to the data of the evaluation device 100 itself, most of the data obtained by other evaluation devices 100, 100' are used as basic data to calculate the reference fog signal or learn the complete model. Therefore, more basic data can be accumulated in the short term, and the evaluation accuracy of the aging condition can be improved over time.

(第4實施例) 圖20係用以說明本發明之第4實施例之老化條件評估裝置的功能的主要部分的模式圖。對於圖20中與在第1實施例-第3實施例中所說明的要素相同或對應的要素，標註與前述圖面相同符號且省略說明。 (Fourth embodiment) FIG. 20 is a schematic diagram of the main parts for explaining the functions of the aging condition evaluation device of the fourth embodiment of the present invention. For the elements in FIG. 20 that are the same as or correspond to the elements described in the first to third embodiments, the same symbols as those in the aforementioned figures are marked and the description is omitted.

本實施例係霧度訊號的取得方法的變化。在載台ST的平移載台的移動軸上係設定有試料收授位置Pa、檢查開始位置Pb，藉由驅動平移載台，載台ST沿著通過該等位置的直線移動。檢查開始位置Pb係對試料W照射照明光而開始試料W的檢查的位置，且為試料W的中心與照明光學系統A的射束點BS相一致的位置。試料收授位置Pa係對載台ST藉由臂Am將試料W安裝卸下(裝載及卸載)的位置，收取到試料W的載台ST由試料收授位置Pa移動至檢查開始位置Pb。This embodiment is a variation of the method of obtaining the haze signal. A sample receiving and accepting position Pa and an inspection starting position Pb are set on the moving axis of the translation stage of the stage ST. By driving the translation stage, the stage ST moves along a straight line passing through these positions. The inspection starting position Pb is the position where the sample W is irradiated with illumination light to start the inspection of the sample W, and is the position where the center of the sample W coincides with the beam spot BS of the illumination optical system A. The sample receiving and accepting position Pa is the position where the sample W is mounted and unmounted (loaded and unloaded) on the stage ST by the arm Am. The stage ST that has received the sample W moves from the sample receiving and accepting position Pa to the inspection starting position Pb.

依近年來更高感度檢查的要求，檢測光學系統Bn係接近試料W作配置。載台ST位於檢測光學系統Bn的正下方時的載台ST與檢測光學系統Bn的間隙G係幾mm左右或其以下。由於難以在檢查開始位置Pb以臂Am將試料W***至間隙G而置放在載台ST，因此採用在遠離檢查開始位置Pb的試料收授位置Pa收授試料W的構成。In accordance with the requirements of higher sensitivity inspection in recent years, the detection optical system Bn is arranged close to the sample W. When the stage ST is located directly below the detection optical system Bn, the gap G between the stage ST and the detection optical system Bn is about several mm or less. Since it is difficult to insert the sample W into the gap G with the arm Am at the inspection start position Pb and place it on the stage ST, a configuration is adopted in which the sample W is received and delivered at the sample receiving and delivering position Pa far from the inspection start position Pb.

在缺陷檢查中，載台ST由檢查開始位置Pb移動的期間一般對試料W掃描P偏光的照明光，惟在本實施例中係在載台ST由試料收授位置Pa移動至檢查開始位置Pb的期間實施預備掃描。在預備掃描中，照明光設定為S偏光，試料W係以由外周側朝向中心的螺旋軌道作掃描。接著，根據在該預備掃描所得的霧度訊號，執行老化條件的評估處理。In defect inspection, the sample W is generally scanned with P-polarized illumination light while the stage ST moves from the inspection start position Pb. However, in this embodiment, a preliminary scan is performed while the stage ST moves from the sample receiving position Pa to the inspection start position Pb. In the preliminary scan, the illumination light is set to S-polarized light, and the sample W is scanned in a spiral track from the periphery to the center. Then, based on the haze signal obtained in the preliminary scan, an evaluation process of the aging condition is performed.

關於其他點，本實施例係與第1實施例、第2實施例或第3實施例相同。Regarding other points, this embodiment is the same as the first embodiment, the second embodiment or the third embodiment.

在此，試料W的缺陷檢查係一般以抑制在缺陷檢查中成為雜訊的霧度光的發生的方式設定檢查條件(例如照明光被設定為P偏光)。因此，依其他條件，亦可假想以試料W的缺陷檢查並無法充分檢測霧度光，難以進行根據霧度訊號的老化條件的評估。Here, the defect inspection of sample W is generally performed by setting the inspection conditions in a manner to suppress the generation of haze light that becomes noise during the defect inspection (for example, the illumination light is set to P polarization). Therefore, according to other conditions, it can be assumed that the defect inspection of sample W cannot fully detect haze light, and it is difficult to evaluate the aging condition based on the haze signal.

相對於此，在本實施例中，可利用試料W由試料收授位置Pa移動至檢查開始位置Pb的機會，以與缺陷檢查不同的條件執行預備檢查來收集霧度訊號。藉由如上所示將試料W的搬送動作利用在霧度訊號的收集，無須變更缺陷檢查時的一連串機械動作，可兼顧缺陷檢查與老化條件評估。In contrast, in this embodiment, the opportunity of sample W moving from the sample receiving position Pa to the inspection start position Pb can be used to perform a preliminary inspection under conditions different from the defect inspection to collect the mist signal. By utilizing the transport action of the sample W in the collection of the mist signal as shown above, there is no need to change the series of mechanical actions during the defect inspection, and both the defect inspection and the aging condition evaluation can be taken into account.

其中，在本實施例中係說明了在缺陷檢查前，試料W由試料收授位置Pa移動至檢查開始位置Pb時取得霧度訊號之例，惟亦考慮在缺陷檢查後，試料W移動至試料收授位置Pa時取得霧度訊號的構成。Among them, in this embodiment, an example of obtaining a mist signal when the sample W moves from the sample receiving position Pa to the inspection start position Pb before defect inspection is explained, but the structure of obtaining a mist signal when the sample W moves to the sample receiving position Pa after defect inspection is also considered.

(變形例) 例如，亦假想如圖2所示若使試料W旋轉來進行掃描時，即使為同一檢測光學系統Bn，霧度光的強度亦依試料W的旋轉角而變化的情形。此時，亦可形成為在有關同一試料W的老化條件評估中，檢測光學系統Bn的選擇按照試料W的旋轉角而周期性作切換的構成。例如若將附圖案晶圓作為試料W進行旋轉掃描時，有因在縱橫周期性形成的微細線狀的圖案所發生的繞射的影響，霧度光的散射方向規則性發生變化的情形。如上所示之情形下，預先規定試料W的旋轉角與檢測光學系統Bn的選擇的關係資料而記憶在例如記憶裝置DB，在老化條件評估中，檢測光學系統Bn的選擇依試料W的旋轉角作切換的構成可成為有效。 (Variation) For example, it is also assumed that if the sample W is rotated and scanned as shown in FIG2, the intensity of the haze light changes depending on the rotation angle of the sample W even if the same detection optical system Bn is used. In this case, it is also possible to form a configuration in which the selection of the detection optical system Bn is periodically switched according to the rotation angle of the sample W in the aging condition evaluation of the same sample W. For example, if a patterned wafer is used as the sample W for rotational scanning, there is a situation in which the scattering direction of the haze light changes regularly due to the influence of diffraction caused by the fine linear pattern formed periodically in the vertical and horizontal directions. In the case shown above, the relationship data between the rotation angle of the sample W and the selection of the detection optical system Bn is predetermined and stored in, for example, a storage device DB. In the aging condition evaluation, the selection of the detection optical system Bn is switched according to the rotation angle of the sample W, which can be effective.

此外，亦考慮不僅霧度訊號，針對同一試料W，針對霧度訊號與缺陷訊號的資料集，將與老化條件等的相關進行解析或機械學習，根據霧度訊號及缺陷訊號評估老化條件。亦考慮起因於老化條件的不完備而在第1片試料W發生缺陷的可能性、或該缺陷影響霧度光，與霧度訊號一併監視缺陷訊號，藉此有老化條件評估的精度提升的可能性。In addition, not only the haze signal, but also the data set of the haze signal and the defect signal for the same sample W is analyzed or machine-learned in relation to the aging conditions, and the aging conditions are evaluated based on the haze signal and the defect signal. The possibility of a defect occurring in the first sample W due to the imperfection of the aging conditions, or the defect affecting the haze light, is also considered, and the defect signal is monitored together with the haze signal, thereby having the possibility of improving the accuracy of the aging condition evaluation.

此外，如前所述，在電漿蝕刻裝置係有在電漿放電狀態的監視用裝載OES的情形。亦考慮將藉由該OES所為之電漿蝕刻中的監視資料與霧度訊號一併在訊號處理裝置D或伺服器等進行解析或機械學習。若可特定電漿放電狀態與監視資料霧度訊號的相關，可期待更進一步的老化條件評估的精度提升。In addition, as mentioned above, in the plasma etching device, there is a case where an OES is installed for monitoring the plasma discharge state. It is also considered that the monitoring data and the mist signal during plasma etching by the OES are analyzed or machine-learned together in the signal processing device D or server. If the correlation between the plasma discharge state and the monitoring data mist signal can be determined, it is expected that the accuracy of aging condition evaluation can be further improved.

此外，缺陷檢查係在半導體製造製程的過程中每逢經由1個或幾個工程即被執行，可取得藉由診斷對象的製程裝置所為之製程的前後的缺陷檢查時的霧度訊號。亦考慮針對同一試料W，運算製程的前後的霧度訊號的差分，藉由該差分，來評估製程裝置的處理的程度。亦即，針對基準試料，將在製程的前後的檢查中所得的霧度訊號的差分作為有關製程裝置的處理的程度的基準霧度訊號來進行運算，將有關試料W的同樣差分與基準霧度訊號作比較，亦考慮作為老化條件評估的一形態。In addition, defect inspection is performed every time one or more processes are passed through the semiconductor manufacturing process, and the haze signal before and after the process can be obtained by the process device of the diagnostic object. It is also considered to calculate the difference of the haze signal before and after the process for the same sample W, and evaluate the degree of processing of the process device by the difference. That is, for the reference sample, the difference of the haze signal obtained in the inspection before and after the process is used as the reference haze signal of the degree of processing of the process device for calculation, and the same difference related to the sample W is compared with the reference haze signal, which is also considered as a form of aging condition evaluation.

此外，在第4實施例中說明了有別於缺陷檢查，以容易發生霧度光的條件掃描試料W來取得霧度訊號之例。此時，缺陷檢查時亦取得霧度光，對以容易發生霧度光的條件與不易發生的條件所取樣到的霧度訊號作比較或解析差分，藉此可掌握霧度訊號與老化條件的新相關。In addition, in the fourth embodiment, an example is described in which a haze signal is obtained by scanning a sample W under a condition where haze light is easily generated, which is different from defect inspection. In this case, haze light is also obtained during defect inspection, and the haze signals sampled under the condition where haze light is easily generated and the condition where haze light is not easily generated are compared or analyzed for difference, thereby grasping a new correlation between the haze signal and the aging condition.

此外，在各實施例中係說明了如前述將入射至開口α3、α4、α1、α6的霧度訊號使用在老化條件評估之例。但是，入射至其他開口的霧度訊號亦可利用在老化條件評估。針對例如入射至位於射束點BS的左右的開口α2、α5、β2、β3、β5、β6的霧度訊號、與入射至開口α3、α4、α1、α6的霧度訊號的加算訊號或差分訊號，可找出與老化條件的相關。In addition, in each embodiment, the haze signal incident to the openings α3, α4, α1, and α6 is used in the aging condition evaluation as described above. However, the haze signal incident to other openings can also be used in the aging condition evaluation. For example, the haze signal incident to the openings α2, α5, β2, β3, β5, and β6 located on the left and right of the beam spot BS and the added signal or the differential signal of the haze signal incident to the openings α3, α4, α1, and α6 can be used to find the correlation with the aging condition.

100,100’,100”:老化條件評估裝置 A:照明光學系統 A1:雷射光源 A2:衰減器 A2a:第1偏光板 A2b:1/2波長板 A2c:第2偏光板 A3:出射光調整單元 A3a,A3b:反射鏡 A4:擴束器 A4a,A4b:透鏡 A5:偏光控制單元 A5a:1/2波長板 A5b:1/4波長板 A6:聚光光學單元 A7-A9:反射鏡 A8a:調整機構 Am:臂 Ba:接物鏡(聚光透鏡) Bb:偏光板 Bc:偏光分光器 Bd,Bd’:成像透鏡(鏡筒透鏡) Be,Be’:視野光圈 Bn(n=1,2…):檢測光學系統 BS:射束點 B’1:反射鏡 B’2:偏光控制單元 B’3:偏光分光器 Cn(n=1,2…):感測器 D:訊號處理裝置 D1:記憶體 D2:缺陷判定電路 D3:低通濾波器電路 D4:老化條件評估電路 D9:神經網路 DB:記憶裝置 DS:資料伺服器 E1:控制裝置 E2:輸入裝置 E3:監視器 F:批次 G:間隙 LD1:照明強度分布(照明輪廓) LD2:照明強度分布(照明輪廓) N:法線 OA:光軸 Pa:試料收授位置 Pb:檢查開始位置 s1,s2:方向 ST:載台 ST1:試料台 ST2:掃描裝置 W:試料 α1-α6,β1-β6,γ:開口 ϕ1,ϕ2:角 100,100’,100”: Aging condition evaluation device A: Illumination optical system A1: Laser light source A2: Attenuator A2a: 1st polarizer A2b: 1/2 wavelength plate A2c: 2nd polarizer A3: Output light adjustment unit A3a,A3b: Reflector A4: Beam expander A4a,A4b: Lens A5: Polarization control unit A5a: 1/2 wavelength plate A5b: 1/4 wavelength plate A6: Focusing optical unit A7-A9: Reflector A8a: Adjustment mechanism Am: Arm Ba: Mirror (focusing lens) Bb: Polarizer Bc: Polarizing beam splitter Bd,Bd’: Imaging lens (tube lens) Be, Be’: field of view aperture Bn (n=1, 2…): detection optical system BS: beam spot B’1: reflector B’2: polarization control unit B’3: polarization beam splitter Cn (n=1, 2…): sensor D: signal processing device D1: memory D2: defect judgment circuit D3: low-pass filter circuit D4: aging condition evaluation circuit D9: neural network DB: memory device DS: data server E1: control device E2: input device E3: monitor F: batch G: gap LD1: illumination intensity distribution (illumination profile) LD2: illumination intensity distribution (illumination profile) N: normal OA: optical axis Pa: sample receiving and sending position Pb: inspection start position s1,s2:direction ST:carrier ST1:sample stage ST2:scanning device W:sample α1-α6,β1-β6,γ:opening ϕ1,ϕ2:angle

[圖1]係本發明之第1實施例之老化條件評估裝置之一構成例的模式圖 [圖2]係表示試料的掃描軌道的模式圖 [圖3]係表示試料的掃描軌道的模式圖 [圖4]係將衰減器抽出表示的模式圖 [圖5]係表示由斜方被導至試料的表面的照明光的光軸與照明強度分布形狀的位置關係的模式圖 [圖6]係表示由斜方被導至試料的表面的照明光的光軸與照明強度分布形狀的位置關係的模式圖 [圖7]係表示由上方觀看，檢測光學系統捕集散射光的區域的圖 [圖8]係模式表示低角及高角的檢測光學系統的天頂角的圖 [圖9]係表示低角的檢測光學系統的方位角的平面圖 [圖10]係表示高角的檢測光學系統的方位角的平面圖 [圖11]係將檢測光學系統的構成圖之例抽出表示的模式圖 [圖12]係本發明之第1實施例之老化條件評估裝置所具備的訊號處理裝置的主要部分的功能區塊圖之一例 [圖13]係表示由半導體的研究開發至製造的工程中評估製程裝置的老化條件的典型場面的流程圖 [圖14]係表示製程裝置的老化條件評估的流程之例的模式流程圖 [圖15]係表示製程裝置的腔室的溫度的歷時變化的模式圖 [圖16]係表示伴隨製程裝置的腔室的溫度的歷時變化而在試料出現的影響的模式圖 [圖17]係表示藉由本發明之第1實施例之老化條件評估裝置所為之老化條件的評估處理的順序的流程圖 [圖18]係本發明之第2實施例之機械學習的概念圖 [圖19]係將本發明之第3實施例之老化條件評估裝置的主要部分抽出表示的模式圖 [圖20]係用以說明本發明之第4實施例之老化條件評估裝置的功能的主要部分的模式圖 [Figure 1] is a schematic diagram of one configuration example of the aging condition evaluation device of the first embodiment of the present invention [Figure 2] is a schematic diagram showing the scanning trajectory of the sample [Figure 3] is a schematic diagram showing the scanning trajectory of the sample [Figure 4] is a schematic diagram showing the attenuator extracted [Figure 5] is a schematic diagram showing the positional relationship between the optical axis of the illumination light guided to the surface of the sample from an oblique angle and the shape of the illumination intensity distribution [Figure 6] is a schematic diagram showing the positional relationship between the optical axis of the illumination light guided to the surface of the sample from an oblique angle and the shape of the illumination intensity distribution [Figure 7] is a diagram showing the area where the detection optical system captures scattered light when viewed from above [Figure 8] is a diagram schematically showing the zenith angles of the low-angle and high-angle detection optical systems [Figure 9] is a plan view showing the azimuth angle of the low-angle detection optical system [Figure 10] is a plan view showing the azimuth angle of the high-angle detection optical system [Figure 11] is a schematic diagram showing an example of the structure diagram of the detection optical system [Figure 12] is an example of a functional block diagram of the main part of the signal processing device of the aging condition evaluation device of the first embodiment of the present invention [Figure 13] is a flow chart showing a typical scene of evaluating the aging condition of a process device in the process from semiconductor research and development to manufacturing [Figure 14] is a schematic flow chart showing an example of the process of evaluating the aging condition of a process device [Figure 15] is a schematic diagram showing the time-varying temperature of the chamber of the process device [Figure 16] is a schematic diagram showing the influence on the sample accompanying the time-varying temperature of the chamber of the process device [Figure 17] is a flow chart showing the order of the evaluation process of the aging condition by the aging condition evaluation device of the first embodiment of the present invention [Figure 18] is a conceptual diagram of the mechanical learning of the second embodiment of the present invention [Figure 19] is a schematic diagram showing the main parts of the aging condition evaluation device of the third embodiment of the present invention [Figure 20] is a schematic diagram of the main parts used to illustrate the functions of the aging condition evaluation device of the fourth embodiment of the present invention

Claims (10)

一種老化條件評估裝置，其係評估製程裝置的老化處理的設定條件亦即老化條件的老化條件評估裝置，其特徵為： 具備： 試料台，其係支持在前述製程裝置被處理的試料； 照明光學系統，其係對載置於前述試料台的試料照射照明光； 複數檢測光學系統，其係將來自前述試料的光聚光而轉換為電訊號且輸出檢測訊號；及 訊號處理裝置，其係處理前述複數檢測光學系統的檢測訊號， 前述訊號處理裝置係掃描在前述製程裝置中伴隨老化處理所處理的1批次的試料之中初期被處理的初期試料來抽出前述初期試料的霧度訊號， 藉由將前述初期試料的前述霧度訊號與基準霧度訊號作比較時的差，來判定老化條件的適當與否。 An aging condition evaluation device is an aging condition evaluation device for evaluating the setting conditions of the aging treatment of a process device, namely, the aging conditions, and is characterized by: It is equipped with: A sample table, which supports the sample to be processed in the aforementioned process device; An illumination optical system, which irradiates the sample placed on the aforementioned sample table with illumination light; A plurality of detection optical systems, which focus the light from the aforementioned sample and convert it into an electrical signal and output the detection signal; and A signal processing device, which processes the detection signal of the aforementioned plurality of detection optical systems, The aforementioned signal processing device scans an initial sample that is initially processed among a batch of samples processed in the aforementioned process device accompanying the aging treatment to extract the haze signal of the aforementioned initial sample, The appropriateness of the aging conditions is determined by comparing the difference between the aforementioned fog signal of the initial sample and the reference fog signal. 如請求項1之老化條件評估裝置，其中，前述訊號處理裝置係將被儲存在記憶裝置的前述初期試料的霧度訊號、與藉由從在前述製程裝置處理前述初期試料之後經過了預定時間後被處理的試料被抽出的霧度訊號所得之基準霧度訊號作比較。An aging condition evaluation device as claimed in claim 1, wherein the signal processing device compares the mist signal of the initial sample stored in the memory device with a reference mist signal obtained by extracting a mist signal from a sample processed a predetermined time after the initial sample is processed by the process device. 如請求項2之老化條件評估裝置，其中，前述訊號處理裝置係在前述檢測光學系統的檢測訊號之中，將頻率大於預定值者作為缺陷訊號、將小於前述預定值者作為霧度訊號來進行處理， 針對前述1批次內的試料，輸出缺陷檢查結果與前述老化條件的適當與否之雙方。 As in claim 2, the aging condition evaluation device, wherein the signal processing device processes the detection signal of the detection optical system as a defect signal if the frequency is greater than a predetermined value and as a haze signal if the frequency is less than the predetermined value, and outputs both the defect inspection result and the suitability of the aging condition for the samples in the batch. 如請求項1之老化條件評估裝置，其中，前述基準霧度訊號係掃描前述1批次的試料之中最後被處理的試料或後半被處理的試料所被實測到的實測值、或實績值或理論值。As in claim 1, the aging condition evaluation device, wherein the reference fog signal is an actual value, an actual value or a theoretical value measured by scanning the last processed sample or the second half processed sample among the samples of the batch. 如請求項1之老化條件評估裝置，其中，前述訊號處理裝置係根據前述霧度訊號及前述基準霧度訊號的差，感測作為前述初期試料的微視表面形狀而出現的前述製程裝置的狀況的變化。As in claim 1, the aging condition evaluation device, wherein the signal processing device senses changes in the condition of the process device caused by the microscopic surface shape of the initial sample based on the difference between the haze signal and the reference haze signal. 如請求項1之老化條件評估裝置，其中，前述複數檢測光學系統係以對前述照明光的射束點的方位角分別不同的方式作配置。As in claim 1, the aging condition evaluation device, wherein the plurality of detection optical systems are configured in a manner such that the azimuth angles of the beam points of the illumination light are respectively different. 如請求項6之老化條件評估裝置，其中，前述訊號處理裝置係根據關於預先儲存在記憶裝置的複數檢測光學系統與霧度訊號的變動要因的相關資料，在前述複數檢測光學系統之中，根據與前述變動要因為相關更強出現的檢測光學系統的霧度訊號，評估老化條件的適當與否。An aging condition evaluation device as claimed in claim 6, wherein the signal processing device evaluates the appropriateness of the aging condition based on relevant data about a plurality of detection optical systems and variation factors of a haze signal pre-stored in a memory device, and, among the plurality of detection optical systems, based on the haze signal of the detection optical system that appears more strongly correlated with the variation factors, evaluates the appropriateness of the aging condition. 如請求項1之老化條件評估裝置，其中，前述訊號處理裝置係針對前述試料，作成前述霧度訊號的強度分布亦即霧度圖， 將前述霧度圖與前述基準霧度訊號的強度分布亦即霧度圖作比較，以前述霧度訊號及前述基準霧度訊號的差是否超過設定值來評估前述老化條件。 As in claim 1, the aging condition evaluation device, wherein the signal processing device generates the intensity distribution of the mist signal, i.e., a mist map, for the sample, and compares the mist map with the intensity distribution of the reference mist signal, i.e., a mist map, to evaluate the aging condition by determining whether the difference between the mist signal and the reference mist signal exceeds a set value. 如請求項1之老化條件評估裝置，其中，前述訊號處理裝置係蓄積關於前述老化條件的評估的資料進行機械學習，根據在機械學習所得的學習完畢模型來評估前述老化條件。As in claim 1, the aging condition evaluation device, wherein the signal processing device accumulates data related to the evaluation of the aging condition to perform machine learning, and evaluates the aging condition based on the learning model obtained in the machine learning. 一種老化條件設定方法，其係將半導體製程裝置所具備的腔室調整至預定的狀況的老化條件的設定方法， 對前述腔室施行第1老化條件之後，在該腔室內設置試料， 在前述腔室內依序處理為複數試料， 即使為與前述第1老化條件不同的參數的第2老化條件亦同樣地依序處理複數試料，以老化條件評估裝置測定該試料，且取得複數霧度訊號， 若由前述試料所得的霧度訊號與基準霧度訊號的差，相較於第1老化條件，以第2老化條件為較小時，即選擇第2老化條件。 A method for setting aging conditions, which is a method for setting aging conditions for adjusting a chamber of a semiconductor process device to a predetermined state, After applying a first aging condition to the chamber, a sample is set in the chamber, A plurality of samples are processed sequentially in the chamber, Even if a second aging condition having parameters different from those of the first aging condition is applied, the plurality of samples are processed sequentially in the same manner, the samples are measured by an aging condition evaluation device, and a plurality of fog signals are obtained, If the difference between the fog signal obtained from the sample and the reference fog signal is smaller than that of the first aging condition, the second aging condition is selected.

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