TWI671796B - Exposure device - Google Patents

Abstract

確認在曝光裝置中簡單且精確地檢出聚焦狀態。 Confirm that the focus state is easily and accurately detected in the exposure device.

在移動平台12的同時，藉由將由桿狀圖案PL1~PL4所構成的圖案列PT投影至形成有狹縫ST1~ST6的遮光單元40，從光感測器PD輸出光量訊號。然後，根據自光量訊號求得的振幅比M，判斷是否維持聚焦狀態。 While moving the platform 12, a pattern line PT composed of rod-shaped patterns PL1 to PL4 is projected onto the light shielding unit 40 formed with the slits ST1 to ST6, and a light quantity signal is output from the light sensor PD. Then, based on the amplitude ratio M obtained from the light amount signal, it is determined whether or not the focus state is maintained.

Description

曝光裝置 Exposure device

本發明係關於用光學調變單元陣列等形成圖案的曝光裝置，且特別有關於焦點檢出。 The present invention relates to an exposure device that is patterned using an optical modulation unit array or the like, and particularly relates to focus detection.

無光罩曝光裝置中，沿著掃描方向移動搭載基板的平台(stage)時，藉由DMD(Digital Micro-mirror Device)等的光學調變單元陣列將圖案光投影至基板上。其中，為了以對應至搭載於平台之基板上的投影區域(曝光區域)位置的方式投影圖案光，控制2維排列的光學調變單元(微鏡等)。 In a maskless exposure apparatus, when a stage on which a substrate is mounted is moved in the scanning direction, a pattern light is projected onto the substrate by an optical modulation unit array such as a DMD (Digital Micro-mirror Device). Among them, in order to project the pattern light so as to correspond to the position of the projection area (exposure area) on the substrate mounted on the platform, the two-dimensional array of optical modulation units (micromirrors, etc.) is controlled.

為了將圖案光的焦點位置校準至塗佈或黏附感光材料的基板上面，在曝光前會進行焦點調整。舉例而言，在焦點調整時，當在光軸方向上移動聚焦透鏡的時候，以接近投影光學系統之解析度界限的週期，將線與間隙圖案(line & space pattern，L/S pattern)的光藉由DMD投影。在投影光學系統的下方設置有CCD相機，當CCD相機接受圖案光時，藉由影像處理算出L/S圖案的對比相關值。然後，將峰值檢出位置定為聚焦位置，調整基板位置(參照專利文獻1)。 In order to align the focal position of the pattern light on the substrate coated or adhered with the photosensitive material, the focus adjustment is performed before the exposure. For example, during focus adjustment, when the focus lens is moved in the direction of the optical axis, the line and space pattern (L / S pattern) is changed at a period close to the resolution limit of the projection optical system. Light is projected by DMD. A CCD camera is provided below the projection optical system. When the CCD camera receives the pattern light, it calculates the contrast correlation value of the L / S pattern by image processing. Then, the peak detection position is set as the focus position, and the substrate position is adjusted (see Patent Document 1).

曝光裝置的光學系統的焦點位置有隨時間變化的情況。因此，即使曾進行焦點調整，仍有焦點位置在聚焦位置以外的可能。特別是，近年來，隨著圖案的細微化，焦點深度 有變淺的傾向，因此容易在聚焦位置以外。為此，藉由觀察用相機，觀察投影至虛擬基板上的光束，在設定使對比最大的聚焦透鏡位置的同時，進行隨時間變化校準調整此位置上的基板與光學系統之間的距離(標準距離)的校正操作(參照專利文獻2)。 The focal position of the optical system of the exposure device may change with time. Therefore, even if the focus adjustment is performed, there is still a possibility that the focus position is outside the focus position. In particular, in recent years, with the miniaturization of patterns, the depth of focus There is a tendency to become shallow, so it is easy to be out of focus. Therefore, the observation camera observes the light beam projected onto the virtual substrate, and sets the focus lens position that maximizes the contrast, and performs time-varying calibration to adjust the distance between the substrate and the optical system at this position (standard Distance) (refer to Patent Document 2).

另一方面，曝光裝置中，若因為光源壽命而造成輸出下降，會無法得到所需的曝光量。此外，會有因為DMD的微鏡操作不良等而造成局部光量不均的情況。為了判斷光量是否滿足規格條件等，在曝光裝置中設置光量感測器，在曝光前投影量測用的圖案光以進行光量檢出(參照專利文獻3)。 On the other hand, in the exposure device, if the output is reduced due to the life of the light source, the required exposure cannot be obtained. In addition, there may be cases in which the local light amount is uneven due to poor operation of the micromirror of the DMD. In order to determine whether the amount of light meets the specifications or the like, a light amount sensor is provided in the exposure device, and pattern light for measurement is projected before the exposure to detect the amount of light (see Patent Document 3).

其中，在曝光裝置中設置直接量測光源光量的光感測器、量測照射至基板之光的光量的光量感測器以及量測DMD的反射光的光感測器。在調整光源的輸出特性的情況下，藉由配置於光源與DMD之間的光感測器檢出光量。另一方面，在調整DMD的光學特性、投影光學系統的光學特性的情況下，設置於繪圖工作台的光感測器在各微鏡為ON狀態的時候接受圖案光。 The exposure device is provided with a light sensor that directly measures the light quantity of the light source, a light quantity sensor that measures the light quantity of the light irradiated to the substrate, and a light sensor that measures the reflected light of the DMD. When adjusting the output characteristics of the light source, the light amount is detected by a light sensor disposed between the light source and the DMD. On the other hand, when adjusting the optical characteristics of the DMD and the optical characteristics of the projection optical system, the light sensor provided on the drawing table receives pattern light when each micromirror is in an ON state.

【先前技術文獻】[Previous Technical Literature]

【專利文獻】[Patent Literature]

專利文獻1 日本特開2009-246165號公報 Patent Document 1 Japanese Patent Laid-Open No. 2009-246165

專利文獻2 日本特開2013-77677號公報 Patent Document 2 Japanese Patent Application Publication No. 2013-77677

專利文獻3 日本特開2008-242173號公報 Patent Document 3 Japanese Patent Laid-Open No. 2008-242173

若曝光裝置的平台機構或者投影光學系統的配置構造等中發生任何阻礙(變化)，曝光面的位置會在聚焦(焦點)範圍以外。特別是，由於圖案變得細微而使焦點深度變淺，若長時間使用曝光裝置，造成焦點移位的可能性變高 If any obstacle (change) occurs in the platform mechanism of the exposure device or the arrangement structure of the projection optical system, the position of the exposure surface will be outside the focus (focus) range. In particular, the depth of the focus becomes shallower due to the finer pattern. If the exposure device is used for a long time, the possibility of focus shift will increase.

因此，在曝光開始前等的時機下，希望確認基板的位置在聚焦範圍內。舉例而言，可以在試驗用的基板上形成圖案並用目視或者用相機拍照以確認圖案精確度。 Therefore, it is desirable to confirm that the position of the substrate is within the focus range at a timing such as before the start of exposure. For example, a pattern can be formed on a substrate for testing and photographed visually or with a camera to confirm the accuracy of the pattern.

然而，若隨著光源輸出的變動而造成光量變化，圖案像的視覺性能會改變。因此，在只確認是否在聚焦狀態以外的作業中，也需要進行基板的光軸(z軸)方向的移動或者光學系統的驅動等與焦點調整類似的作業。此伴隨著聚焦確認的長作業時間會妨礙基板製造的吞吐量(throughput)改善。 However, if the amount of light is changed as the output of the light source changes, the visual performance of the pattern image will change. Therefore, it is also necessary to perform operations similar to focus adjustment, such as moving the substrate in the optical axis (z-axis) direction or driving the optical system, in operations that only confirm whether or not they are out of focus. This long operation time accompanied by focus confirmation hinders improvement in throughput of substrate manufacturing.

因此，在曝光裝置中，需要可簡單且精確地檢出聚焦狀態的監測。 Therefore, in the exposure apparatus, monitoring that can detect the in-focus state simply and accurately is required.

另一方面，根據曝光裝置的設置狀況，隨著長時間的使用，塵埃或者水蒸氣等會附著於透鏡表面。此外，由於將高亮度的光照射至由樹脂等形成的基板以形成圖案，樹脂成分等汽化而附著於透鏡表面。若因為塵埃等附著於透鏡表面而使光學系統的成像性能降低，圖案解析度會在所要求的解析度程度以外。 On the other hand, depending on the installation condition of the exposure device, dust or water vapor may adhere to the lens surface with long-term use. In addition, since a substrate of a resin or the like is irradiated with high-brightness light to form a pattern, a resin component or the like vaporizes and adheres to the lens surface. If the imaging performance of the optical system is lowered due to the adhesion of dust or the like to the lens surface, the pattern resolution will be outside the required resolution.

在水蒸氣等透明附著物的情況下，由於光量沒有降低僅成像性能降低，藉由監測光源的光量仍無法檢出解析度降低。因此，需要在曝光前確認是否發生解析度降低。然而， 在試驗用基板上形成圖案並根據此形成的圖案判斷解析度，為此將伴隨著長作業時間，妨礙基板製造的吞吐量改善。 In the case of transparent adherends such as water vapor, since the light amount is not reduced, only the imaging performance is reduced, and the decrease in resolution cannot be detected by monitoring the light amount of the light source. Therefore, it is necessary to confirm whether a decrease in resolution has occurred before exposure. however, Forming a pattern on a test substrate and judging the resolution based on the pattern thus formed will cause a long operation time and prevent improvement in throughput of substrate manufacturing.

因此，在曝光裝置中，需要簡單且精確地監測光學系統的解析性能。 Therefore, in the exposure apparatus, it is necessary to monitor the analysis performance of the optical system simply and accurately.

另一方面，在因運行中的熱等而使DMD、例如光學系統之部件劣化的情況下，剛開始會在曝光區域的小範圍內部分造成光量降低，並漸漸地往周邊擴散。舉例而言，在因熱而造成部件性能劣化的情況下，光量降低最一開始在中心部分發生然後往周邊擴散。在歸因為大氣中例如灰塵之異物而造成性能劣化的情況下，光量降低在周邊部分發生並朝中心部分擴散。 On the other hand, when the DMD, such as a component of an optical system, is deteriorated due to heat during operation, the amount of light is initially reduced in a small area of the exposure area and gradually diffuses to the periphery. For example, in the case where the performance of a component is deteriorated due to heat, a decrease in the amount of light first occurs at the center portion and then diffuses to the periphery. In the case where the performance is deteriorated due to foreign matter such as dust in the atmosphere, a decrease in the amount of light occurs in the peripheral portion and diffuses toward the central portion.

然而，僅設置光感測器而只進行光量檢出，由於無法檢查曝光區域整體的光量分佈，因此難以判別是起因於部件劣化等的局部光量降低還是起因於燈輸出降低等的整體光量降低。此外，由於量測間隔受限於光量感測器的單元尺寸，所檢出的量測值係階段式地變化，難以正確檢知光量降低區域。 However, only the light sensor is provided and only the light amount is detected. Since the light amount distribution of the entire exposed area cannot be checked, it is difficult to discriminate whether the local light amount is reduced due to deterioration of a component or the like, or the total light amount is reduced due to a reduction in lamp output. In addition, since the measurement interval is limited by the unit size of the light amount sensor, the detected measurement value changes step by step, and it is difficult to accurately detect the light amount reduction region.

因此，在曝光裝置中，需要簡單且精確地監測起因於部件劣化等的光量降低。 Therefore, in the exposure apparatus, it is necessary to simply and accurately monitor the decrease in the amount of light due to deterioration of the components and the like.

本發明之曝光裝置，包括：複數個光學調變單元排列成矩陣形狀的光學調變單元陣列、將光學調變單元陣列的曝光區域相對於被描繪體沿著主掃描方向相對移動的掃描單元、根據對應於曝光區域之相對位置的圖案資料控制複數個光 學調變單元的曝光控制單元、將來自光學調變單元陣列的圖案光成像至被描繪體的描繪面的成像光學系統、沿著上述描繪面形成至少1個狹縫的遮光單元、接受透過狹縫的光的測光單元以及根據測光單元的輸出檢出聚焦狀態的聚焦檢出單元。 The exposure device of the present invention includes an optical modulation unit array in which a plurality of optical modulation units are arranged in a matrix shape, a scanning unit that relatively moves an exposure area of the optical modulation unit array in a main scanning direction with respect to a subject, and Controlling multiple lights based on pattern data corresponding to the relative position of the exposed area An exposure control unit that learns a modulation unit, an imaging optical system that images pattern light from an optical modulation unit array onto a drawing surface of a subject, a light-shielding unit that forms at least one slit along the drawing surface, and receives a transmission slit. A photometric unit for slit light and a focus detection unit that detects a focus state based on an output of the photometry unit.

本發明之曝光控制單元，在上述曝光區域對上述遮光單元相對移動的時候，投影線與間隙(L/S)圖案光。藉由L/S圖案光在相對移動的同時通過狹縫，根據測光單元的輸出檢出波形狀光量。在此，「波形狀光量」係表示沿著掃描方向之光量變化成為週期性波形狀的空間光量分佈。雖然測光單元的輸出為具有時間序列週期性的波形輸出(稱時間序列波形狀光量)，但得到光量變化的特性與時間序列波形狀光量相應的空間光量分佈。 In the exposure control unit of the present invention, when the exposure area is relatively moved to the light shielding unit, the projection line and the gap (L / S) pattern light. The L / S pattern light passes through the slit while moving relatively, and the wave-shaped light amount is detected based on the output of the photometric unit. Here, the "wave shape light quantity" means a spatial light quantity distribution in which the light quantity change along the scanning direction becomes a periodic wave shape. Although the output of the photometric unit is a waveform output having a time series periodicity (called a time series wave shape light amount), a spatial light amount distribution corresponding to a characteristic of a change in light amount and a time series wave shape light amount is obtained.

然後，聚焦檢出單元，根據藉由L/S圖案光的投影所檢出的波形狀光量的振幅(也就是光量變化的幅度)以及在聚焦範圍中時的標準振幅，檢出描繪面是否在聚焦範圍中。在此，「在聚焦範圍中時的標準振幅」係表示基於焦點深度判斷為聚焦的狀態下所檢出的波形狀光量的振幅。藉由根據振幅的聚焦判斷，在不驅動基板或光學系統下可確認聚焦狀態。另外，藉由觀察相對於標準振幅的振幅變化而非對比度，可經由較簡單的演算處理進行聚焦判斷。 Then, the focus detection unit detects whether the drawing surface is in accordance with the amplitude of the wave shape light amount (that is, the amplitude of the light amount change) detected by the projection of the L / S pattern light and the standard amplitude when it is in the focus range. Focusing range. Here, the "standard amplitude when in focus range" means the amplitude of the wave-shaped light amount detected in a state where it is determined to be in focus based on the depth of focus. By the focus judgment based on the amplitude, the focus state can be confirmed without driving the substrate or the optical system. In addition, by observing the amplitude change with respect to the standard amplitude instead of the contrast, the focus judgment can be performed through a simpler calculation process.

舉例而言，聚焦檢出單元，根據相當於光量振幅與標準振幅之比的振幅比，判斷是否在聚焦範圍中。藉由振幅比的簡單演算處理，可進行聚焦判斷。特別是，在聚焦狀態與非聚焦狀態下的波形狀光量的中心光量(平均光量)相等的情況 下，聚焦檢出單元根據L/S圖案光的平均光量以及沒投影L/S圖案光時的基本光量可算出標準振幅。對於波形狀光量振幅，可檢出最大光量與最小光量(Peak to Peak)。 For example, the focus detection unit determines whether or not it is in the focus range based on an amplitude ratio corresponding to the ratio of the light amount amplitude to the standard amplitude. With simple calculation of the amplitude ratio, focus judgment can be performed. In particular, when the center light amount (average light amount) of the wave shape light amount in the focused state and the unfocused state is equal Next, the focus detection unit can calculate a standard amplitude based on the average light amount of the L / S pattern light and the basic light amount when the L / S pattern light is not projected. For the wave shape light quantity amplitude, the maximum light quantity and the minimum light quantity (Peak to Peak) can be detected.

聚焦檢出單元，可在預先驅動光學系統與基板的焦點調整時，量測各焦點位置的振幅比，作為焦點檢出用資料而保存於記憶體。在此情況下，根據資料所決定的聚焦範圍，聚焦檢出單元可判斷是否在聚焦範圍中。聚焦範圍可根據感光材料的感光特性、所要求的圖案精確度其中至少一者而定。 The focus detection unit can measure the amplitude ratio of each focus position when the focus adjustment of the optical system and the substrate is driven in advance, and stores it in the memory as the focus detection data. In this case, the focus detection unit can determine whether it is in the focus range based on the focus range determined by the data. The focusing range can be determined according to at least one of the photosensitive characteristics of the photosensitive material and the required pattern accuracy.

在算出平均光量的情況下，可設置專用的開口單元以及受光單元。舉例而言，遮光單元具有平均光量量測用開口單元，而測光單元具有接受通過平均光量量測用開口單元的L/S圖案光的平均光量量測用受光單元。 When calculating the average light amount, a dedicated opening unit and a light receiving unit can be provided. For example, the light shielding unit has an opening unit for average light quantity measurement, and the light measuring unit has a light receiving unit for average light quantity measurement that receives L / S pattern light passing through the opening unit for average light quantity measurement.

若考慮到迅速將不在聚焦範圍通知給操作者，在聚焦範圍以外的情況下，可設置通知在聚焦範圍以外之事的通知單元。 In consideration of promptly notifying the operator of the out-of-focus range, a notification unit for notifying the out-of-focus range may be provided in the case of out-of-focus range.

曝光裝置可設置在曝光區域對遮光單元相對移動的時候，根據藉由投影曝光位置檢出用的L/S圖案光而從測光單元輸出的光量，檢出曝光位置的曝光位置檢出單元。在此情況下，可藉由相同機構進行曝光位置檢出與焦點檢出兩者。 The exposure device may be provided when the exposure area is relatively moved to the light shielding unit, and the exposure position detection unit that detects the exposure position is based on the amount of light output from the photometry unit by projecting the exposure position detection L / S pattern light. In this case, both the exposure position detection and the focus detection can be performed by the same mechanism.

本發明其他態樣的曝光裝置的焦點檢出裝置，包括：接受線與間隙(L/S)圖案光的測光單元，根據藉由L/S圖案光的投影所檢出的波形狀光量的振幅以及對應於聚焦範圍的標準振幅檢出被描繪面是否在聚焦範圍中的聚焦檢出單元。另外，本發明其他態樣的曝光裝置的焦點檢出方法，接受線與間 隙(L/S)圖案光，根據藉由L/S圖案光的投影所檢出的波形狀光量的振幅以及對應於聚焦範圍的標準振幅檢出被描繪面是否在聚焦範圍中。 A focus detection device of an exposure device according to another aspect of the present invention includes a photometric unit that receives line and gap (L / S) pattern light, and an amplitude of a wave shape light amount detected by projection of the L / S pattern light. And a focus detection unit that detects whether the imaged surface is in the focus range with a standard amplitude corresponding to the focus range. In addition, the focus detection method of the exposure apparatus of another aspect of the present invention accepts line-to-line The gap (L / S) pattern light detects whether or not the surface being drawn is in the focus range based on the amplitude of the wave-shaped light amount detected by the projection of the L / S pattern light and the standard amplitude corresponding to the focus range.

另一方面，本發明其他態樣的曝光裝置，包括：複數個光學調變單元排列成矩陣形狀的光學調變單元陣列、將光學調變單元陣列的曝光區域相對於被描繪體沿著主掃描方向相對移動的掃描單元、根據對應於上述曝光區域之相對位置的圖案資料控制複數個光學調變單元的曝光控制單元、將來自光學調變單元陣列的圖案光成像至上述被描繪體的描繪面的成像光學系統、沿著描繪面形成至少1個狹縫的遮光單元、接受透過狹縫的光的測光單元以及根據來自測光單元的輸出檢出成像光學系統的解析能力的解析能力檢出單元。 On the other hand, an exposure apparatus according to another aspect of the present invention includes an optical modulation unit array in which a plurality of optical modulation units are arranged in a matrix shape, and an exposure area of the optical modulation unit array is scanned along a main scan with respect to the object to be drawn. A scanning unit that moves relatively in a direction, an exposure control unit that controls a plurality of optical modulation units based on pattern data corresponding to the relative positions of the exposure areas, and image the pattern light from the optical modulation unit array onto the drawing surface of the object to be drawn Imaging optical system, a light shielding unit forming at least one slit along the drawing surface, a photometric unit that receives light passing through the slit, and an analysis capability detection unit that detects the analysis capability of the imaging optical system based on the output from the photometric unit.

本發明之曝光控制單元，在曝光區域對遮光單元相對移動的時候，投影線與間隙(L/S)圖案光。藉由L/S圖案光在相對移動的同時通過狹縫，根據測光單元的輸出檢出波形狀光量。在此，「波形狀光量」係表示沿著掃描方向之光量變化成為週期性波形狀的空間光量分佈。雖然測光單元的輸出為具有時間序列週期性的波形輸出(稱時間序列波形狀光量)，但得到光量變化的特性與時間序列波形狀光量相應的空間光量分佈。 In the exposure control unit of the present invention, when the exposure area is relatively moved to the light shielding unit, the projection line and the gap (L / S) pattern light. The L / S pattern light passes through the slit while moving relatively, and the wave-shaped light amount is detected based on the output of the photometric unit. Here, the "wave shape light quantity" means a spatial light quantity distribution in which the light quantity change along the scanning direction becomes a periodic wave shape. Although the output of the photometric unit is a waveform output having a time series periodicity (called a time series wave shape light amount), a spatial light amount distribution corresponding to a characteristic of a change in light amount and a time series wave shape light amount is obtained.

然後，解析能力檢出單元，根據藉由L/S圖案光的投影所檢出的波形狀光量的振幅(也就是光量變化的幅度)以及具有預定的界限解析能力以上的解析能力時的標準振幅，檢出解析能力是否比界限解析能力低。 Then, the resolution detection unit detects the amplitude of the wave-shaped light amount (that is, the amplitude of the change in light amount) detected by the projection of the L / S pattern light and the standard amplitude when the resolution is greater than a predetermined limit resolution. , Check if the resolution is lower than the limit resolution.

舉例而言，解析能力檢出單元，根據相當於所檢出之振幅與標準振幅之比的振幅比，可判斷解析能力是否比界限解析能力低。藉由振幅比算出的簡單演算處理，可監測解析能力。 For example, the analysis capability detection unit can determine whether the analysis capability is lower than the limit analysis capability based on an amplitude ratio corresponding to the ratio of the detected amplitude to the standard amplitude. With simple calculation processing for calculating the amplitude ratio, the analytical capability can be monitored.

特別是，在具有解析能力時與解析能力降低時兩者的波形狀光量的中心光量(平均光量)相等的情況下，解析能力檢出單元根據L/S圖案光的平均光量以及沒投影L/S圖案光時的基本光量可算出標準振幅。對於波形狀光量振幅，可檢出最大光量與最小光量(Peak to Peak)。 In particular, when the center light amount (average light amount) of the wave-shaped light amount is equal when the analysis ability is reduced and when the analysis ability is reduced, the analysis ability detection unit is based on the average light quantity of the L / S pattern light and the L / S is not projected. The basic amount of light in the S-pattern light can be used to calculate the standard amplitude. For the wave shape light quantity amplitude, the maximum light quantity and the minimum light quantity (Peak to Peak) can be detected.

解析能力檢出單元，根據振幅比與成像光學系統的解析能力之間的對應關係，可判斷解析能力是否比界限解析能力低。舉例而言，在焦點調整時，或者在出貨等時，將表示成像光學系統的解析能力與振幅比之間的關係的資料儲存於記憶體，在解析能力檢出時，根據資料可進行判斷。成像光學系統的界限解析能力，可根據成像光學系統的光學性能而定。 The analysis capability detection unit can determine whether the analysis capability is lower than the limit analysis capability based on the correspondence between the amplitude ratio and the analysis capability of the imaging optical system. For example, at the time of focus adjustment, or at the time of shipment, data indicating the relationship between the resolution capability of the imaging optical system and the amplitude ratio is stored in the memory. When the resolution capability is detected, it can be judged based on the data. . The resolution capability of the imaging optical system can be determined according to the optical performance of the imaging optical system.

在算出平均光量的情況下，可設置專用的開口單元以及受光單元。舉例而言，遮光單元具有平均光量量測用開口單元，而測光單元具有接受通過平均光量量測用開口單元的L/S圖案光的平均光量量測用受光單元。 When calculating the average light amount, a dedicated opening unit and a light receiving unit can be provided. For example, the light shielding unit has an opening unit for average light quantity measurement, and the light measuring unit has a light receiving unit for average light quantity measurement that receives L / S pattern light passing through the average light quantity measurement opening unit.

若考慮到迅速將不在聚焦範圍通知給操作者，在聚焦範圍以外的情況下，可設置通知在聚焦範圍以外之事的通知單元。 In consideration of promptly notifying the operator of the out-of-focus range, a notification unit for notifying the out-of-focus range may be provided in the case of out-of-focus range.

曝光裝置可設置在曝光區域對遮光單元相對移動的時候，根據藉由投影曝光位置檢出用的L/S圖案光而從測光 單元輸出的光量，檢出曝光位置的曝光位置檢出單元。在此情況下，可藉由相同機構進行曝光位置檢出與焦點檢出兩者。 The exposure device can be set to measure light based on the L / S pattern light for detection by projecting the exposure position when the exposure area moves relative to the light-shielding unit. The amount of light output by the unit is an exposure position detection unit that detects the exposure position. In this case, both the exposure position detection and the focus detection can be performed by the same mechanism.

本發明其他態樣的曝光裝置的解析能力檢出裝置，包括：接受透過狹縫的線與間隙(L/S)圖案光的測光單元，根據藉由L/S圖案光的投影所檢出的波形狀光量的振幅以及具有預定的界限解析能力以上的解析能力時的標準振幅檢出所檢出之解析能力是否比界限解析能力低的解析能力檢出單元。另外，本發明其他態樣的曝光裝置的曝光方法，接受透過狹縫的線與間隙(L/S)圖案光，根據藉由L/S圖案光的投影所檢出的波形狀光量的振幅以及具有預定的界限解析能力以上的解析能力時的標準振幅，檢出解析能力是否比界限解析能力低。 An analysis capability detection device for an exposure device according to another aspect of the present invention includes a photometric unit that receives line and gap (L / S) pattern light passing through a slit, and detects the light based on the projection of the L / S pattern light. The amplitude of the wave shape light amount and a standard amplitude detection unit that has a resolution capability equal to or greater than a predetermined limit resolution capability, and a resolution capability detection unit that detects whether the resolution capability detected is lower than the limit resolution capability. In addition, the exposure method of another aspect of the exposure device of the present invention accepts line and gap (L / S) pattern light passing through a slit, and according to the amplitude of the wave shape light amount detected by projection of the L / S pattern light and The standard amplitude when the analysis capability is greater than or equal to the predetermined limit analysis capability, and it is detected whether the analysis capability is lower than the limit analysis capability.

另一方面，本發明其他態樣的本發明的曝光裝置，包括：複數個光學調變單元排列成矩陣形狀的光學調變單元陣列、將光學調變單元陣列的曝光區域相對於被描繪體沿著主掃描方向相對移動的掃描單元、控制複數個光學調變單元並將沿著主掃描方向排列的線與間隙(L/S)圖案的光投影至被描繪體的曝光控制單元、接受通過相對於L/S圖案之線方向傾斜的細長的測光區域的光的測光單元以及根據L/S圖案對測光區域相對移動時來自測光單元的輸出檢出曝光區域的光量分佈的光量檢出單元。舉例而言，測光單元包括形成具有對應於測光區域之尺寸的狹縫的遮光單元。 On the other hand, the exposure apparatus of the present invention in another aspect of the present invention includes an optical modulation unit array in which a plurality of optical modulation units are arranged in a matrix shape, and the exposure area of the optical modulation unit array is aligned with respect to the subject. A scanning unit moving relatively in the main scanning direction, controlling a plurality of optical modulation units, and projecting light of a line and a gap (L / S) pattern aligned along the main scanning direction to an exposure control unit of the subject, receiving A light metering unit for light in an elongated metering area inclined in the direction of the line of the L / S pattern and a light quantity detection unit for detecting a light quantity distribution of the exposure area from the output of the light metering unit when the light metering area is relatively moved according to the L / S pattern. For example, the photometric unit includes a light-shielding unit formed with a slit having a size corresponding to a photometric area.

在本發明中，L/S圖案的間距係決定為使L/S圖案的各線狀圖案的光量依序被量測。也就是說，決定使用於與其 間距一致的線狀圖案光投影的光學調變元件。在此，「光量依序被量測」係表示，某線狀圖案通過測光區域時下一個線狀圖案不會前進至測光區域，各線狀圖案各自通過時的光量變化係表示一個接一個依序量測。 In the present invention, the pitch of the L / S pattern is determined so that the light amount of each linear pattern of the L / S pattern is sequentially measured. That is, the decision to use Optical modulation element for projecting linear pattern light with uniform pitch. Here, "the light quantity is sequentially measured" means that when a linear pattern passes through the light metering area, the next linear pattern will not advance to the light metering area, and the light quantity change when each linear pattern passes each other means one by one in order. Measure.

舉例而言，測光區域相對於線方向傾斜的角度可滿足下列式子：Lytanθ<PP，其中，Ly表示L/S圖案沿著副掃描方向的長度，θ表示傾斜角度，PP表示L/S圖案的間距。 For example, the angle of the metering area relative to the line direction can satisfy the following formula: Lytanθ <PP, where Ly represents the length of the L / S pattern along the sub-scanning direction, θ represents the tilt angle, and PP represents the L / S pattern Pitch.

另外，測光區域相對於線方向傾斜的角度，對應光學調變單元陣列的垂直水平尺寸，可將此傾斜角度定為37°或者30°以下。舉例而言，可將傾斜角度θ定為1.2°<θ<2.8°。 In addition, the tilt angle of the photometric area with respect to the line direction corresponds to the vertical and horizontal size of the optical modulation unit array. This tilt angle can be set to 37 ° or less than 30 °. For example, the inclination angle θ can be set to 1.2 ° <θ <2.8 °.

光量檢出單元，根據光量分佈，可判斷曝光區域中的光量比是否在預定的閾值以下。在光量為閾值以下的情況下，可設置通知此結果的通知單元。另外，光量檢出單元可作成曝光區域的光量分佈圖。 The light amount detection unit can determine whether the light amount ratio in the exposure area is below a predetermined threshold based on the light amount distribution. In the case where the amount of light is below the threshold, a notification unit that notifies this result may be provided. In addition, the light amount detection unit can create a light amount distribution map of the exposure area.

本發明其他態樣中的曝光方法，將複數個光學調變單元排列成矩陣形狀的光學調變單元陣列的曝光區域相對於被描繪體沿著主掃描方向相對移動的掃描單元，控制複數個光學調變單元，將沿著主掃描方向排列的線與間隙(L/S)圖案的光投影至被描繪體，接受通過相對於L/S圖案之線方向傾斜的細長的測光區域的光，根據L/S圖案對測光區域相對移動時來自測光單元的輸出，檢出曝光區域的光量分佈。L/S圖案的間距係決定為使L/S圖案的各線狀圖案的光量依序被量測。 In the exposure method in another aspect of the present invention, a plurality of optical modulation units are arranged in a matrix shape, and an exposure area of an optical modulation unit array is moved relative to a scanning unit in a main scanning direction of the object to be controlled. The modulation unit projects the light of the line and gap (L / S) pattern arranged along the main scanning direction onto the object, and receives the light passing through the elongated light metering area inclined with respect to the line direction of the L / S pattern. The L / S pattern detects the light quantity distribution of the exposure area based on the output from the photometry unit when the photometry area is relatively moved. The pitch of the L / S pattern is determined so that the light amount of each linear pattern of the L / S pattern is sequentially measured.

本發明其他態樣中的曝光裝置用測光裝置，包括：設置於搭載包括複數個光學調變單元排列成矩陣形狀的光學調變單元陣列的曝光裝置的被描繪體的平台，並且具有相對於規定至平台的副掃描方向傾斜的狹縫的遮光單元，以及接受通過狹縫的光的測光單元，其中，狹縫相對副掃描方向的傾斜角度定為37°以下。另外，與此測光裝置連動動作曝光裝置，包括：複數個光學調變單元排列成矩陣形狀的光學調變單元陣列、將光學調變單元陣列的曝光區域相對於被描繪體沿著主掃描方向相對移動的掃描單元、控制複數個光學調變單元並且將沿著主掃描方向排列的間距定為使各線狀圖案光量依序被量測的線與間隙(L/S)圖案的光投影至上述被描繪體的曝光控制單元、根據來自測光單元的輸出檢出曝光區域的光量分佈的光量檢出單元。 A light metering device for an exposure device according to another aspect of the present invention includes: a platform provided on a subject to be drawn, which is provided with an exposure device including an array of optical modulation units arranged in a matrix shape; The shading unit of the slit inclined to the sub-scanning direction to the platform and the photometric unit receiving light passing through the slit, wherein the tilt angle of the slit with respect to the sub-scanning direction is set to 37 ° or less. In addition, the exposure device that operates in conjunction with this photometric device includes an optical modulation unit array in which a plurality of optical modulation units are arranged in a matrix shape, and an exposure area of the optical modulation unit array is opposed to the subject in the main scanning direction. The moving scanning unit, the plurality of optical modulation units are controlled, and the pitch arranged along the main scanning direction is set so that the light of the line and gap (L / S) pattern in which the light amount of each linear pattern is sequentially measured is projected onto the above-mentioned object. The exposure control unit of the drawing body and the light quantity detection unit that detects the light quantity distribution of the exposure area based on the output from the photometry unit.

根據本發明，在曝光裝置中，可以簡單且精確地檢出或確認聚焦狀態。 According to the present invention, in the exposure apparatus, the in-focus state can be easily detected and confirmed.

另外，根據本發明，可以簡單且精確地監測光學系統的解析性能。 In addition, according to the present invention, the analysis performance of the optical system can be simply and accurately monitored.

再者，根據本發明，可以簡單且精確地監測光學系統性能。 Furthermore, according to the present invention, the performance of the optical system can be simply and accurately monitored.

10‧‧‧曝光裝置 10‧‧‧Exposure device

12‧‧‧平台 12‧‧‧ platform

15‧‧‧平台驅動機構 15‧‧‧Platform-driven mechanism

18‧‧‧曝光頭 18‧‧‧ exposure head

20‧‧‧光源 20‧‧‧ light source

21‧‧‧光源驅動單元 21‧‧‧light source drive unit

22‧‧‧DMD(光學調變單元陣列) 22‧‧‧DMD (Optical Modulation Unit Array)

23‧‧‧成像光學系統 23‧‧‧ Imaging Optical System

24‧‧‧DMD驅動電路 24‧‧‧DMD driving circuit

25‧‧‧稜鏡 25‧‧‧ 稜鏡

26‧‧‧光柵轉換電路 26‧‧‧Grating conversion circuit

27‧‧‧演算單元(光量檢出單元) 27‧‧‧Calculation unit (light quantity detection unit)

28‧‧‧光檢出單元(測光單元) 28‧‧‧light detection unit (photometry unit)

29‧‧‧脈衝訊號產生單元 29‧‧‧ Pulse signal generating unit

30‧‧‧控制器(曝光控制單元、光量檢出單元、通知單元) 30‧‧‧ controller (exposure control unit, light amount detection unit, notification unit)

32‧‧‧記憶體 32‧‧‧Memory

33‧‧‧稜鏡驅動單元 33‧‧‧ 稜鏡 Drive unit

40‧‧‧遮光單元 40‧‧‧ Shading Unit

50‧‧‧支持機構 50‧‧‧ Supporting Organizations

60‧‧‧支持機構 60‧‧‧ Supporting Organizations

A‧‧‧振幅 A‧‧‧amplitude

AL‧‧‧光量訊號分佈 AL‧‧‧Light quantity signal distribution

AR‧‧‧聚焦範圍 AR‧‧‧Focus range

AR0‧‧‧振幅比最大之聚焦範圍 AR0‧‧‧Focus range with maximum amplitude ratio

B‧‧‧標準振幅 B‧‧‧Standard amplitude

BE‧‧‧有效範圍 BE‧‧‧ Effective range

C‧‧‧中心位置 C‧‧‧Central location

CG‧‧‧曲線 CG‧‧‧ Curve

d‧‧‧移動間距 d‧‧‧moving distance

DPL、DPL1、DPLm‧‧‧光量分佈 DPL, DPL1, DPLm‧‧‧ Light distribution

D0‧‧‧界限振幅比 D0‧‧‧ Limit amplitude ratio

EL‧‧‧端部 EL‧‧‧End

FP‧‧‧聚焦位置 FP‧‧‧Focus position

GD、GD’、GD1、GD2‧‧‧光量分佈 GD, GD ’, GD1, GD2‧‧‧light distribution

K‧‧‧圖案寬度 K‧‧‧Pattern width

L‧‧‧量測長度 L‧‧‧Measured length

LG‧‧‧光量分佈 LG‧‧‧ Light Distribution

LT1、LT2‧‧‧長度方向側 LT1, LT2‧‧‧length side

Lx‧‧‧寬度 Lx‧‧‧Width

Ly‧‧‧圖案長度 Ly‧‧‧ pattern length

M‧‧‧振幅比 M‧‧‧ amplitude ratio

ML‧‧‧最小光量 ML‧‧‧Minimum amount of light

MM‧‧‧最大光量 MM‧‧‧Maximum amount of light

P、P’‧‧‧光量峰值 P, P’‧‧‧ peak light

PD‧‧‧光感測器 PD‧‧‧light sensor

PDS‧‧‧測光區域 PDS‧‧‧ Metering area

PDW‧‧‧光感測器寬度 PDW‧‧‧Light sensor width

PL1、PL2、PL3、PL4‧‧‧桿狀圖案 PL1, PL2, PL3, PL4 ‧‧‧ rod pattern

PP‧‧‧間距 PP‧‧‧Pitch

PS‧‧‧受光面 PS‧‧‧ light receiving surface

PT‧‧‧圖案列 PT‧‧‧Pattern Bar

PW‧‧‧整體寬度 PW‧‧‧Overall width

R‧‧‧相交範圍 R‧‧‧ Intersection range

S‧‧‧振幅 S‧‧‧amplitude

SB‧‧‧長度 SB‧‧‧length

SL‧‧‧狹縫(測光區域) SL‧‧‧Slit (metering area)

SLB‧‧‧狹縫寬度 SLB‧‧‧Slit width

SLL‧‧‧長度 SLL‧‧‧length

SP‧‧‧狹縫間距 SP‧‧‧Slit pitch

ST、ST1、ST2、ST3、ST4、ST5、ST6‧‧‧狹縫 ST, ST1, ST2, ST3, ST4, ST5, ST6

S101、S102、...、S104、S201、S202、...、S204‧‧‧步驟 S101, S102, ..., S104, S201, S202, ..., S204‧‧‧ steps

T‧‧‧厚度 T‧‧‧thickness

T1、T2‧‧‧點 T1, T2‧‧‧‧ points

W‧‧‧基板 W‧‧‧ substrate

X‧‧‧主掃描方向 X‧‧‧Main scanning direction

Y‧‧‧副掃描方向 Y‧‧‧ sub-scanning direction

Z‧‧‧狹縫寬度 Z‧‧‧Slit width

第1圖係第1實施形態之曝光裝置的示意圖。 FIG. 1 is a schematic diagram of an exposure apparatus according to the first embodiment.

第2圖係表示遮光單元與焦點調整以及焦點檢出用的圖案 列的圖。 Fig. 2 shows a pattern for shading unit, focus adjustment and focus detection Column diagram.

第3圖係表示光感測器與遮光單元之配置的概略側視圖。 Fig. 3 is a schematic side view showing the arrangement of a light sensor and a light shielding unit.

第4圖係表示1個桿狀圖案的光通過1個狹縫時的空間光量分佈以及時間序列光量分佈的圖形的示意圖。 FIG. 4 is a schematic diagram showing a spatial light quantity distribution and a time-series light quantity distribution when light of one rod-shaped pattern passes through one slit.

第5圖係1個桿狀圖案的光通過1個狹縫時的空間光量分佈的圖形的示意圖。 FIG. 5 is a schematic diagram of a spatial light amount distribution pattern when light of one rod-shaped pattern passes through one slit.

第6圖係表示對應至桿狀圖案列的空間光量分佈的圖。 FIG. 6 is a diagram showing a spatial light amount distribution corresponding to a bar-shaped pattern row.

第7圖係表示不同振幅比的空間光量分佈的圖。 Fig. 7 is a diagram showing spatial light quantity distributions with different amplitude ratios.

第8圖係表示焦點移動量與振幅比的相關關係的圖形的示意圖。 FIG. 8 is a diagram showing a graph showing the correlation between the amount of focus movement and the amplitude ratio.

第9圖係表示聚焦狀態監測處理的流程的圖。 FIG. 9 is a diagram showing a flow of focus state monitoring processing.

第10圖係表示維持解析性能的情況下的光量分佈與解析性能降低的情況下的光量分佈的圖。 Fig. 10 is a diagram showing a light amount distribution when the analysis performance is maintained and a light amount distribution when the analysis performance is reduced.

第11圖係表示解析能力與振幅比之間的相關關係的圖形的示意圖。 FIG. 11 is a diagram showing a graph showing a correlation between an analysis capability and an amplitude ratio.

第12圖係表示標準振幅的空間光量分佈的圖。 Fig. 12 is a diagram showing a spatial light quantity distribution with a standard amplitude.

第13圖係表示解析性能的監測處理的流程的圖。 FIG. 13 is a diagram showing a flow of monitoring processing of analysis performance.

第14圖係表示遮光單元與光量分佈量測用的圖案列的圖。 Fig. 14 is a diagram showing a light-shielding unit and a pattern row for measuring a light amount distribution.

第15A圖係表示1個桿狀圖案PL1通過狹縫SL之過程的圖。 FIG. 15A is a diagram showing a process in which one rod-shaped pattern PL1 passes through the slit SL.

第15B圖係表示1個桿狀圖案PL1通過狹縫SL之過程的圖。 FIG. 15B is a diagram showing a process in which one rod-shaped pattern PL1 passes through the slit SL.

第15C圖係表示1個桿狀圖案PL1通過狹縫SL之過程的圖。 FIG. 15C is a diagram showing a process in which one rod-shaped pattern PL1 passes through the slit SL.

第15D圖係表示1個桿狀圖案PL1通過狹縫SL之過程的圖。 FIG. 15D is a diagram showing a process in which one rod pattern PL1 passes through the slit SL.

第16圖係1個桿狀圖案PL1通過狹縫SL時所取得的沿著副掃描方向的光量分佈。 FIG. 16 is a light amount distribution along the sub-scanning direction obtained when one rod pattern PL1 passes through the slit SL.

第17圖係表示與光感測器的光量檢出時間間隔一致的狹縫的移動間距的圖。 FIG. 17 is a diagram showing a moving pitch of a slit in accordance with a light amount detection time interval of a photo sensor.

第18圖係表示重疊對應各桿狀圖案的光量分佈的圖。 Fig. 18 is a diagram showing light quantity distributions corresponding to respective rod-shaped patterns superimposed.

第19圖係3維表示對應曝光區域整體的光量分佈的圖。 FIG. 19 is a three-dimensional view showing a light amount distribution corresponding to the entire exposed area.

第20圖係表示光量分佈量測與警告處理的流程圖。 Fig. 20 is a flowchart showing light quantity distribution measurement and warning processing.

以下參照圖式說明本發明的實施型態。 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

第1圖係第1實施形態之曝光裝置的示意圖。 FIG. 1 is a schematic diagram of an exposure apparatus according to the first embodiment.

曝光裝置10為藉由向塗佈或貼附光阻等感光材料之基板W照射光以形成圖案的無光罩曝光裝置，搭載基板W的平台12設置為可沿著掃描方向移動。平台驅動機構15可沿著主掃描方向X、副掃描方向Y移動平台12。 The exposure device 10 is a maskless exposure device that irradiates light onto a substrate W to which a photosensitive material such as a photoresist is applied or attached to form a pattern. The stage 12 on which the substrate W is mounted is provided to be movable in the scanning direction. The platform driving mechanism 15 can move the platform 12 along the main scanning direction X and the sub scanning direction Y.

曝光裝置10包括投影圖案光的複數個曝光頭(此處僅圖示1個曝光頭18)，曝光頭18包括DMD 22、照明光學系統(未圖示)、成像光學系統23。光源20由例如放電燈(未圖示)所構成，由光源驅動單元21驅動。 The exposure device 10 includes a plurality of exposure heads (only one exposure head 18 is shown here) that project pattern light. The exposure head 18 includes a DMD 22, an illumination optical system (not shown), and an imaging optical system 23. The light source 20 is composed of, for example, a discharge lamp (not shown), and is driven by a light source driving unit 21.

當由向量資料構成的CAD/CAM資料輸入至曝光裝置10時，向量資料送至光柵(raster)轉換電路26，向量資料被轉換為光柵資料。所生成的光柵資料在暫時儲存於緩衝記憶體(未圖示)之後送至DMD驅動電路24。 When CAD / CAM data composed of vector data is input to the exposure device 10, the vector data is sent to a raster conversion circuit 26, and the vector data is converted into raster data. The generated raster data is temporarily stored in a buffer memory (not shown) and sent to the DMD driving circuit 24.

DMD 22為2維排列微小微鏡的光學調變單元陣列(光調變器)，各微鏡藉由變化姿勢選擇性地切換光的反射方向。由DMD驅動電路24對各微鏡進行姿勢控制，藉此，將對應至圖案的光透過成像光學系統23投影(成像)至基板W的表面。據此，形成圖案像於基板W。 DMD 22 is an optical modulation unit array (light modulator) in which two-dimensional micro-mirrors are arranged. Each micro-mirror selectively switches the direction of light reflection by changing the posture. The DMD driving circuit 24 controls the posture of each micromirror, thereby projecting (imaging) the light corresponding to the pattern onto the surface of the substrate W through the imaging optical system 23. Accordingly, a pattern image is formed on the substrate W.

平台驅動機構15根據來自控制器30的訊號移動平台12。平台驅動機構15中包括未圖示的線性編碼器，其量測平台12的位置並回饋至控制器30。控制器30控制曝光裝置10的動作，輸出控制訊號至平台驅動機構15、DMD驅動電路24。另外，執行用於將功能表畫面等顯示至未圖示的螢幕的顯示控制處理。與曝光動作有關的程式係預先儲存於記憶體32。 The platform driving mechanism 15 moves the platform 12 based on a signal from the controller 30. The platform driving mechanism 15 includes a linear encoder (not shown), which measures the position of the platform 12 and feeds it back to the controller 30. The controller 30 controls the operation of the exposure device 10 and outputs a control signal to the platform driving mechanism 15 and the DMD driving circuit 24. A display control process for displaying a menu screen or the like on a screen (not shown) is also executed. The program related to the exposure operation is stored in the memory 32 in advance.

光檢出單元28係設置於平台12的端部附近，包括光感測器PD以及脈衝訊號產生單元29。在光檢出單元28的上方，設置通過部分光的遮光單元40。光檢出單元28係在焦點調整以及校準調整時使用。演算單元27，基於送自光檢出單元28的訊號，算出作為用於監測聚焦狀態之參數的光量振幅比。另外演算單元27可算出曝光位置，即相對於曝光頭的基板W(平台12)的位置。 The light detection unit 28 is disposed near the end of the platform 12 and includes a light sensor PD and a pulse signal generating unit 29. Above the light detection unit 28, a light blocking unit 40 that passes a part of the light is provided. The light detection unit 28 is used for focus adjustment and calibration adjustment. The calculation unit 27 calculates a light amount amplitude ratio as a parameter for monitoring a focus state based on a signal sent from the light detection unit 28. In addition, the calculation unit 27 can calculate an exposure position, that is, a position with respect to the substrate W (stage 12) of the exposure head.

在成像光學系統23與遮光單元40之間的光路上設置的焦點調整用稜鏡25為對向配置2個楔型稜鏡以互相用斜面相接而成的光學系統，稜鏡驅動單元33互相相對移動2個稜鏡以使光軸方向厚度改變。成像光學系統23的焦點位置，藉由驅動稜鏡25，沿著基板垂直方向(z軸方向)移動。 The focus adjustment 稜鏡 25 provided on the optical path between the imaging optical system 23 and the light-shielding unit 40 is an optical system in which two wedge-shaped 稜鏡 s are arranged opposite to each other so as to be connected to each other with inclined surfaces, and the drive units 33 are mutually Relatively move 2 稜鏡 to change the thickness in the optical axis direction. The focus position of the imaging optical system 23 is moved along the substrate vertical direction (z-axis direction) by driving the 稜鏡 25.

曝光動作中，平台12沿著掃描方向X以一定速度 移動。DMD 22整體的投影區域(以下稱為曝光區域)，伴隨著基板W的移動，在基板W上相對地移動。曝光動作根據預定的曝光間距進行，控制微鏡與曝光間距一致地投影圖案光。 During the exposure operation, the stage 12 moves along the scanning direction X at a constant speed mobile. The entire projection area of the DMD 22 (hereinafter referred to as an exposure area) moves relatively on the substrate W along with the movement of the substrate W. The exposure operation is performed according to a predetermined exposure pitch, and the micromirror is controlled to project the pattern light in accordance with the exposure pitch.

根據曝光區域的相對位置調整DMD 22的各微鏡的控制時機，藉此依序投影待描繪至曝光區域之位置的圖案光。然後，經由包括曝光頭18的複數個曝光頭描繪基板W整體，藉此，在基板W整體形成圖案。 The control timing of each micromirror of the DMD 22 is adjusted according to the relative position of the exposure area, thereby sequentially projecting the pattern light to be drawn to the position of the exposure area. Then, the entire substrate W is drawn through the plurality of exposure heads including the exposure heads 18, whereby a pattern is formed on the entire substrate W.

另外，關於曝光方式，不只是以一定速度移動的連續移動方式，也可以是間歇移動的步進重複(step and repeat)。再者，也可以是部分重疊微鏡之像並曝光的多重曝光(重疊曝光)。 In addition, the exposure method is not only a continuous movement method that moves at a constant speed, but also a step and repeat method of intermittent movement. Furthermore, multiple exposure (overlap exposure) may be used in which a micromirror image is partially overlapped and exposed.

在進行基板種類變更等情況下，在曝光前使用焦點調整用稜鏡25進行焦點調整。具體而言，對應基板W或光阻厚度的變更計算焦點調整量，對應焦點調整量驅動焦點調整用稜鏡25，使成像光學系統23的焦點位置與基板W的繪圖面一致。 When the substrate type is changed, focus adjustment is performed using the focus adjustment lens 25 before exposure. Specifically, the focus adjustment amount is calculated according to the change of the substrate W or the thickness of the photoresist, and the focus adjustment 稜鏡 25 is driven according to the change of the focus adjustment amount, so that the focus position of the imaging optical system 23 matches the drawing surface of the substrate W.

進行焦點調整時，在對各基板進行曝光動作前，或者曝光作業時間每經過預定時間的時候，檢出/監測是否維持聚焦狀態。具體而言，以一定速度移動平台12的同時，投影焦點檢出用的圖案光。控制器30基於來自光檢出單元28的輸出訊號，判斷是否在聚焦狀態。 When performing focus adjustment, it is detected / monitored whether or not the focus state is maintained before an exposure operation is performed on each substrate, or every time a predetermined period of exposure operation time elapses. Specifically, while moving the stage 12 at a constant speed, the pattern light for focus detection is projected. The controller 30 determines whether it is in a focused state based on an output signal from the light detection unit 28.

另外，為了在正確位置上形成圖案，在曝光動作開始前進行與曝光開始位置有關的校正處理。具體而言，以一定速度移動平台12的同時投影位置檢出用的圖案光。此處的 位置檢出用的圖案光為與焦點檢出用的圖案光不同的圖案列。控制器30根據送自演算單元27的位置資訊，校正曝光開始位置。 In addition, in order to form a pattern at a correct position, a correction process related to the exposure start position is performed before the exposure operation is started. Specifically, the pattern light for position detection is projected while moving the stage 12 at a constant speed. Here The pattern light for position detection is a pattern row different from the pattern light for focus detection. The controller 30 corrects the exposure start position based on the position information sent from the calculation unit 27.

以下，使用第2~6圖，說明聚焦狀態的檢出、監測。 Hereinafter, the detection and monitoring of the focus state will be described using FIGS. 2 to 6.

第2圖係表示遮光單元、焦點調整以及焦點檢出用的圖案列的圖。第3圖係表示光感測器與遮光單元之配置的概略側視圖。 FIG. 2 is a diagram showing a pattern line for a light shielding unit, focus adjustment, and focus detection. Fig. 3 is a schematic side view showing the arrangement of a light sensor and a light shielding unit.

遮光單元40係配置於光感測器PD的光源側上方，狹縫ST係沿著主掃描方向X形成。在此，垂直於主掃描方向X，即，平行於副掃描方向Y的6個桿狀狹縫ST1~ST6係以狹縫間距SP等間隔形成。遮光單元40的尺寸，比光感測器PD整體的尺寸大，配置於遮光單元40正下方的光感測器PD僅接受通過狹縫ST的光。 The light shielding unit 40 is disposed above the light source side of the photo sensor PD, and the slit ST is formed along the main scanning direction X. Here, six rod-shaped slits ST1 to ST6 that are perpendicular to the main scanning direction X, that is, parallel to the sub-scanning direction Y are formed at regular intervals of the slit pitch SP. The size of the light shielding unit 40 is larger than the overall size of the light sensor PD. The light sensor PD disposed directly below the light shielding unit 40 receives only light passing through the slit ST.

如第3圖所示，檢知光強度/光量的光感測器PD係由支持機構60保持，支持機構60係安裝於平台12。支持機構50支持平行於光感測器之受光面PS與基板W之描繪面的遮光單元40的兩端，並藉由支持機構60保持。 As shown in FIG. 3, the light sensor PD that detects the light intensity / light amount is held by the support mechanism 60, and the support mechanism 60 is mounted on the platform 12. The support mechanism 50 supports both ends of the light shielding unit 40 parallel to the light receiving surface PS of the light sensor and the drawing surface of the substrate W, and is held by the support mechanism 60.

焦點調整以及檢出聚焦狀態的時候，隨著平台12的移動曝光區域通過遮光單元40。此時，向遮光單元40投影第2圖所示的圖案列PT的光。圖案列PT，即所謂的線與間隙(L/S)圖案，為複數並列垂直於主掃描方向X也就是平行於副掃描方向Y之桿狀圖案的圖案列。在此，藉由以圖案間距PP等間隔並排4個桿狀圖案PL1、PL2、PL3、PL4所構成。在此， 圖案列PT的圖案寬度K與線之間間隙的寬度相等。也就是說，圖案間距PP為圖案寬度K的2倍。 When the focus is adjusted and the focus state is detected, the exposure area passes through the light shielding unit 40 as the stage 12 moves. At this time, the light of the pattern row PT shown in FIG. 2 is projected onto the light shielding unit 40. The pattern line PT, a so-called line and gap (L / S) pattern, is a pattern line of a plurality of rod-shaped patterns juxtaposed to the main scanning direction X, that is, parallel to the sub-scanning direction Y. Here, four rod-shaped patterns PL1, PL2, PL3, and PL4 are arranged side by side at equal intervals in the pattern pitch PP. here, The pattern width K of the pattern row PT is equal to the width of the gap between the lines. That is, the pattern pitch PP is twice the pattern width K.

桿狀圖案PL1、PL2、PL3、PL4的各圖案寬度K比形成於遮光單元40的各狹縫ST1~ST6的狹縫寬度Z寬。並且，圖案間距PP也比狹縫寬度Z寬。因此，1個桿狀圖案以預定速度完全通過1個狹縫之後，下一個桿狀圖案開始通過狹縫。此外，桿狀圖案PL1、PL2、PL3、PL4的各圖案寬度K係設定為接近成像光學系統23之解析性能上限的寬度。舉例而言，圖案列PT的圖案寬度K係設定為2個鄰接的2個微鏡像(2單元)的寬度。 The pattern width K of each of the rod patterns PL1, PL2, PL3, and PL4 is wider than the slit width Z of each of the slits ST1 to ST6 formed in the light shielding unit 40. The pattern pitch PP is also wider than the slit width Z. Therefore, after one rod-shaped pattern completely passes through one slit at a predetermined speed, the next rod-shaped pattern starts to pass through the slit. The width K of each pattern of the rod-shaped patterns PL1, PL2, PL3, and PL4 is set to a width close to the upper limit of the analysis performance of the imaging optical system 23. For example, the pattern width K of the pattern row PT is set to the width of two adjacent two micro-mirrors (two cells).

如第2圖所示，圖案列PT沿著主掃描方向X的整體寬度PW比狹縫間距SP小。因此，當圖案列PT的最後端桿狀圖案PL4以一定速度完成通過1個狹縫時，前頭的桿狀圖案PL1開始通過下一個狹縫。 As shown in FIG. 2, the entire width PW of the pattern row PT along the main scanning direction X is smaller than the slit pitch SP. Therefore, when the rod-shaped pattern PL4 at the rear end of the pattern row PT finishes passing through one slit at a certain speed, the rod-shaped pattern PL1 at the front starts to pass through the next slit.

當圖案列PT的光以一定速度通過遮光單元40時，桿狀圖案PL1透過狹縫ST6時從光感測器PD輸出的訊號(以下稱為光量訊號)在時間序列上連續變化。此起因於如上所述的狹縫寬度Z比桿狀圖案PL1的圖案寬度K短。因此，其他桿狀圖案PL2、PL3、PL4依序通過狹縫SL6時也是在時間序列上連續變化。 When the light of the pattern row PT passes the light blocking unit 40 at a certain speed, the signal (hereinafter referred to as a light amount signal) output from the light sensor PD when the rod pattern PL1 passes through the slit ST6 continuously changes in time series. This is because the slit width Z as described above is shorter than the pattern width K of the rod-shaped pattern PL1. Therefore, when the other rod patterns PL2, PL3, and PL4 pass through the slit SL6 in sequence, they also continuously change in time series.

第4圖、第5圖係分別表示1個桿狀圖案的光通過1個狹縫時的空間光量分佈以及時間序列光量分佈為聚焦狀態、失焦狀態的圖形。但是，此處的「空間光量分佈」係表示沿著X方向的光量變化的樣子，並不包括沿著Y方向的光量。 4 and 5 are graphs showing the spatial light quantity distribution and the time-series light quantity distribution when the light of a rod-shaped pattern passes through a slit, respectively, in a focused state and a defocused state. However, the "spatial light quantity distribution" here indicates how the light quantity changes along the X direction, and does not include the light quantity along the Y direction.

接近成像光學系統23的解析度界限的桿狀圖案PL1的沿著主掃描方向X的光強度分佈/光量分佈大致為高斯分佈，以峰值為中心光量往前往後地減少。其結果，藉由光感測器PD檢出的光量的時間序列分佈(以下稱為光量訊號分佈)AL也大致為高斯分佈，時間序列的光量訊號分佈AL與空間的光量分佈GD具有互相相似的相關關係(參照第4圖)。但是，此處的光量訊號分佈AL係表示相對於平台12的移動根據狹縫寬度Z連續繪製所檢出的光量訊號而成的軌跡。 The light intensity distribution / light quantity distribution of the rod pattern PL1 near the resolution limit of the imaging optical system 23 along the main scanning direction X is approximately a Gaussian distribution, and the light quantity decreases toward the rear with the peak as the center. As a result, the time series distribution (hereinafter referred to as the light amount signal distribution) AL of the light amount detected by the light sensor PD is also roughly Gaussian, and the time series light amount signal distribution AL and the spatial light amount distribution GD are similar to each other. Correlation (see Figure 4). However, the light amount signal distribution AL here indicates a trajectory obtained by continuously drawing the detected light amount signal based on the slit width Z with respect to the movement of the stage 12.

光量訊號分佈AL與光量分佈GD具有相似的關係，若狹縫寬度Z比圖案寬度K短，藉由足夠短的狹縫寬度Z，光量訊號分佈AL的山形形狀會變得更接近光量分佈GD的山形形狀。在此，狹縫寬度Z係設定為相對於圖案寬度K的0.1~0.5倍。為了變成此種比率，調整投影桿狀圖案PL1之光的微鏡的區域設定或者狹縫寬度Z的調整其中任一者，或者進行兩者。 The light quantity signal distribution AL has a similar relationship with the light quantity distribution GD. If the slit width Z is shorter than the pattern width K, with a sufficiently short slit width Z, the mountain shape of the light quantity signal distribution AL will become closer to the mountain shape of the light quantity distribution GD. shape. Here, the slit width Z is set to 0.1 to 0.5 times the pattern width K. In order to achieve such a ratio, either one of the area setting of the micromirror of the light projected by the rod-shaped pattern PL1 or the adjustment of the slit width Z, or both are performed.

另一方面，在第5圖中，係表示失焦狀態下的空間光量分佈。在此情況下，雖然光量分佈是緩緩增加的同時經過光量峰值P’後緩緩減少的分佈形狀，但光量峰值P’與聚焦狀態的光量峰值P相比之下較小。這是因為焦點位置與遮光單元40的表面，即，基板W的表面不一致，光量分佈的範圍擴大，因此中心附近的光強度降低。 On the other hand, FIG. 5 shows the spatial light amount distribution in the defocused state. In this case, although the light quantity distribution is a distribution shape that gradually increases while passing through the light quantity peak P 'and then gradually decreases, the light quantity peak P' is smaller than the focused light quantity peak P. This is because the focal position does not coincide with the surface of the light shielding unit 40, that is, the surface of the substrate W, and the range of the light amount distribution is widened, so that the light intensity near the center decreases.

第6圖係表示對應至圖案列PT的空間光量分佈的圖。 FIG. 6 is a diagram showing a spatial light quantity distribution corresponding to the pattern row PT.

在第6圖中，表示連接4個桿狀圖案PL1~PL4 的狹縫通過後的空間光量分佈而成的光量分佈。儘管如此，此分佈是在狹縫形成為與各桿狀圖案位置一致的情況下得到的光量分佈，實際上，是與各桿狀圖案通過一致且依序得到的空間光量分佈。 In Fig. 6, four rod patterns PL1 to PL4 are connected. The light quantity distribution obtained by the spatial light quantity distribution after passing through the slit. However, this distribution is a light quantity distribution obtained when the slits are formed to coincide with the positions of the respective rod-like patterns, and in fact, it is a spatial light quantity distribution obtained in accordance with and sequentially passing through the respective rod-like patterns.

如此所示的一系列光量分佈，係以週期性的波形(波狀)表示，具有自中心的振幅S。在焦點位置得到的振幅S，比失焦時的振幅S’大。儘管如此，如上所述，由於圖案列PT的線/間隙寬度相同(=K)，焦點位置與失焦位置兩者波形的中心皆一致。因此，空間光量分佈的振幅大小，成為表示是否在焦點位置也就是聚焦位置的參數。 The series of light quantity distributions shown in this manner are represented by a periodic waveform (wave shape) and have an amplitude S from the center. The amplitude S obtained at the focus position is larger than the amplitude S 'at the time of defocusing. However, as described above, since the line / gap width of the pattern row PT is the same (= K), the centers of the waveforms of both the focus position and the defocus position are the same. Therefore, the amplitude of the spatial light quantity distribution becomes a parameter indicating whether or not the focal position is the focal position.

第7圖係表示具有不同振幅比的空間光量分佈的圖。 Fig. 7 is a diagram showing spatial light quantity distributions having different amplitude ratios.

如第7圖所示，在聚焦狀態之情況與在聚焦狀態以外之情況下，波形AM的振幅上產生差異。另外，根據焦點深度的範圍，在聚焦狀態中也會得到不同的振幅。另一方面，如上所述，即使振幅不同波形中心位置C實質上沒有變化。這是因為，在光量峰值附近(波形的山部分)發生光量減少部分的同時，光量底部附近(波形的其他部分)發生互補的光量增加部分。 As shown in FIG. 7, a difference occurs in the amplitude of the waveform AM between the case of focusing and the case of being out of focus. In addition, depending on the range of the depth of focus, different amplitudes are obtained in the focused state. On the other hand, as described above, the waveform center position C does not change substantially even if the amplitude is different. This is because, while a light amount decrease portion occurs near the peak of the light amount (the mountain portion of the waveform), a complementary light amount increase portion occurs near the bottom of the light amount (the other portion of the waveform).

因此，將聚焦狀態下的振幅設定為標準，藉由比較作為標準的振幅以及所檢出的空間光量分佈的振幅，即使沒有進行隨著焦點位置變動的焦點調整作業，也可監測是否在聚焦狀態。舉例而言，求出標準振幅與所檢出的振幅的比，決定落在聚焦狀態也就是焦點深度範圍內的振幅比，藉此可監測聚 焦狀態。 Therefore, by setting the amplitude in the focus state as a standard, and comparing the amplitude used as the standard and the amplitude of the detected spatial light quantity distribution, it is possible to monitor whether or not the focus is in place even if the focus adjustment operation that varies with the focus position is not performed. . For example, find the ratio of the standard amplitude to the detected amplitude, and determine the amplitude ratio that falls in the focus state, that is, in the depth range of the focus. Focused state.

順帶一提，如第4圖所示，由於空間光量分佈與時間序列光量分佈有相似關係，藉由在移動平台12的同時將位置檢出用的圖案列PT的光投影至遮光單元40，可得到與第7圖相同的時間序列光量分佈。另外，由於光感測器PD所檢出的時間序列光量分佈的振幅大小係對應至空間光量分佈的振幅大小，時間序列光量分佈的振幅比相當於空間光量分佈的振幅比。因此，根據時間序列光量分佈中的振幅比判斷聚焦狀態成為可能。 Incidentally, as shown in FIG. 4, since the spatial light quantity distribution has a similar relationship with the time series light quantity distribution, by moving the platform 12 while projecting the light of the pattern row PT for position detection to the light-shielding unit 40, The same time-series light quantity distribution as in FIG. 7 is obtained. In addition, since the amplitude of the time-series light quantity distribution detected by the light sensor PD corresponds to the amplitude of the spatial light quantity distribution, the amplitude ratio of the time-series light quantity distribution corresponds to the amplitude ratio of the spatial light quantity distribution. Therefore, it is possible to determine the focus state based on the amplitude ratio in the time-series light quantity distribution.

位置檢出用的圖案列PT的光量為一定時，由於空間光量分佈的中心位置C不論聚焦狀態、非聚焦狀態皆為一定，藉由檢出中心位置與最小或最大光量算出振幅A是可能的。中心位置C，舉例而言，可從空間分佈的峰值光量(最大光量)與底部光量(最小光量)算出。 When the light amount of the pattern line PT for position detection is constant, since the center position C of the spatial light amount distribution is constant regardless of the focused state or the unfocused state, it is possible to calculate the amplitude A by detecting the center position and the minimum or maximum light amount. . The center position C can be calculated from the peak light amount (maximum light amount) and the bottom light amount (minimum light amount) of the spatial distribution, for example.

或者，由於中心位置C等於圖案列PT的1週期(1個線與1個間隙的對)的平均光量，也可設置光感測器等的測光單元以量測光量並求出所量測的圖案列PT的光量的平均值以算出中心位置C。在此，藉由將根據透過各狹縫的光所得到的時間序列光量值對週期積分或平均化，求出中心位置C。 Or, since the center position C is equal to the average light amount of one period (the pair of one line and one gap) of the pattern row PT, a light measuring unit such as a light sensor may be provided to measure the light amount and obtain the measured amount. The average value of the light amount in the pattern row PT is used to calculate the center position C. Here, the center position C is obtained by integrating or averaging the time-series light quantity values obtained from the light passing through the slits to the period.

另一方面，關於成像光學系統23的焦點位置與基板W的表面一致時的振幅(標準振幅)B，藉由檢出沒有投影圖案時所檢出的光量訊號位準(基本光量)，可得到中心位置C與所檢出的光量訊號位準之間的振幅B以作為標準振幅。 On the other hand, regarding the amplitude (standard amplitude) B when the focal position of the imaging optical system 23 coincides with the surface of the substrate W, the light level signal level (basic light level) detected when no projection pattern is detected can be obtained. The amplitude B between the center position C and the detected light quantity signal level is taken as the standard amplitude.

另外，在設置用於算出平均光量的測光單元的情 況中，可設置與上述遮光單元和光感測器不同的獨立的測光部，或者，可由上述遮光單元和/或光感測器兼用測光單元而構成。在此情況下，也可在遮光單元中與上述狹縫不同的位置上另外設置開口單元，以量測通過開口單元的光的光量。開口單元至少比圖案列PT的圖案寬度K寬，較佳可提供具有比圖案列PT整體寬度PW寬之透光部分的開口單元。再者，可另外設置用於量測光量的光感測器，或者，也可藉由上述光感測器測光。 In the case where a photometric unit for calculating an average light amount is provided, In this case, a separate light-measuring unit different from the light-shielding unit and the light sensor may be provided, or the light-shielding unit and / or the light sensor may be used as a light-measuring unit. In this case, an opening unit may be additionally provided at a position different from the slit in the light shielding unit to measure the light amount of light passing through the opening unit. The opening unit is at least wider than the pattern width K of the pattern row PT, and it is preferable to provide an opening unit having a light transmitting portion wider than the entire width PW of the pattern row PT. Furthermore, a light sensor for measuring the light quantity may be separately provided, or light may be measured by the light sensor.

第8圖係表示焦點移動量與振幅比的相關關係的圖形的示意圖。 FIG. 8 is a diagram showing a graph showing the correlation between the amount of focus movement and the amplitude ratio.

在第8圖中，表示在改變焦點位置的同時畫出根據所檢出的光量分佈算出的振幅比。振幅比A/B越大，也就是所檢出的振幅A越接近最大振幅B，越接近聚焦位置，而焦點位置越遠離成像光學系統23的焦點深度，則振幅比A/B越小。 FIG. 8 shows the amplitude ratio calculated from the detected light quantity distribution while changing the focus position. The larger the amplitude ratio A / B, that is, the closer the detected amplitude A is to the maximum amplitude B, the closer it is to the focus position, and the farther the focal position is from the focal depth of the imaging optical system 23, the smaller the amplitude ratio A / B.

因此，在例如出貨時，預先算出焦點移動可能的全部範圍內的振幅比，並將對應至振幅比以及當時成像光學系統23的焦點位置的資料(主資料)儲存至記憶體32。具體而言，以一定速度移動平台12的同時，投影焦點調整用圖案的光。然後，驅動焦點調整用稜鏡25以在移動可能的距離範圍內改變焦點位置的同時，重複進行此操作。 Therefore, for example, at the time of shipment, the amplitude ratio in the entire range where the focus can move is calculated in advance, and data (master data) corresponding to the amplitude ratio and the focal position of the imaging optical system 23 at that time are stored in the memory 32. Specifically, while moving the stage 12 at a constant speed, the light of the focus adjustment pattern is projected. Then, the focus adjustment 稜鏡 25 is driven to repeat the operation while changing the focus position within a possible distance range.

控制器30根據自光檢出單元28輸出的訊號算出振幅比，並建立主資料。並且，基板W的聚焦位置FP係儲存至記憶體32。然後，以聚焦位置FP為中心定義聚焦範圍AR。 The controller 30 calculates an amplitude ratio based on a signal output from the light detection unit 28 and establishes master data. The focus position FP of the substrate W is stored in the memory 32. Then, the focus range AR is defined with the focus position FP as the center.

聚焦位置FP係定義為自振幅比最大之聚焦範圍 AR0偏移的位置。這是因為，遮光單元40的位置與基板W的繪圖面位置僅相差基板W的厚度T(參照第1圖)，並且，遮光單元40的光入射面係設置於比基板W的搭載面(平台表面)稍微低的位置。聚焦範圍AR的寬度(上限、下限)係根據成像光學系統23的焦點深度連同基板W的厚度T、形成於基板W表面的感光材料的種類、所要求的圖案等級等。 The focus position FP is defined as the focus range with the largest amplitude ratio AR0 offset position. This is because the position of the light shielding unit 40 differs from the position of the drawing surface of the substrate W only by the thickness T of the substrate W (see FIG. 1), and the light incident surface of the light shielding unit 40 is provided on the mounting surface (stage) of the substrate W Surface) slightly lower position. The width (upper limit, lower limit) of the focus range AR is based on the depth of focus of the imaging optical system 23 together with the thickness T of the substrate W, the type of photosensitive material formed on the surface of the substrate W, the required pattern level, and the like.

第9圖係表示聚焦狀態監測處理的流程的圖。在此，調整焦點調整用稜鏡25至匹配使用的基板W等而算出的焦點位置之後，各基板的曝光動作開始之前，或者，每經過預定時間時，進行處理。 FIG. 9 is a diagram showing a flow of focus state monitoring processing. Here, the processing is performed after the focus position 稜鏡 25 is adjusted to the focus position calculated by matching the substrate W and the like, before the exposure operation of each substrate is started, or every predetermined time elapses.

控制器30，在移動平台12的同時，為了向遮光單元40照射圖案列PT，控制DMD驅動電路24(S101)。然後，根據自光感測器PD輸出的光量訊號，算出振幅比M(S102)，並判斷來自儲存於記憶體32之主資料中的振幅比M所對應的焦點位置是否包含於聚焦範圍AR(S103)。另外，關於振幅比的演算，也可在控制器30處執行。 The controller 30 controls the DMD driving circuit 24 in order to irradiate the pattern row PT to the light shielding unit 40 while moving the stage 12 (S101). Then, based on the light quantity signal output from the light sensor PD, the amplitude ratio M is calculated (S102), and it is determined whether the focal position corresponding to the amplitude ratio M from the master data stored in the memory 32 is included in the focus range AR ( S103). The calculation of the amplitude ratio may be performed by the controller 30.

若所檢出的振幅比M所對應的焦點位置在聚焦範圍AR以外，控制器30執行用於對顯示器警告顯示的顯示控制處理(S104)。藉此，使用者可知道焦點位置係在聚焦範圍AR以外。另外，也可藉由警告顯示以外的蜂鳴聲產生等其他告知手段通知操作者。 If the focus position corresponding to the detected amplitude ratio M is outside the focus range AR, the controller 30 executes a display control process for warning display on the monitor (S104). Thereby, the user can know that the focus position is outside the focus range AR. In addition, the operator may be notified by other notification means such as beep generation other than the warning display.

因此，根據第1實施形態，在移動平台12的同時，藉由將桿狀圖案PL1~PL4所構成的圖案列PT投影至狹縫ST1~ST6形成的遮光單元40，自光感測器PD輸出光量訊號。然 後，根據自光量訊號求得的振幅比M，判斷是否維持在聚焦狀態。 Therefore, according to the first embodiment, while the platform 12 is moved, the pattern row PT formed by the rod patterns PL1 to PL4 is projected onto the light shielding unit 40 formed by the slits ST1 to ST6, and is output from the light sensor PD. Light signal. Of course Then, based on the amplitude ratio M obtained from the light amount signal, it is determined whether or not the focus state is maintained.

由於不使用解析度受像素尺寸等限制的CCD，而是藉由對基板W掃描焦點檢出用的圖案光以判斷成像光學系統23的聚焦或失焦，可精確檢出聚焦狀態。並且，相對於儲存在記憶體的主資料所決定的聚焦範圍AR，由於振幅比的變化率係單調減少，在發生失焦的情況下，可確實檢出焦點偏離聚焦範圍AR的方向。另一方面，由於光檢出單元28係與曝光位置檢出共同使用，不需要設置焦點檢出專用的CCD，而可降低成本。 Since the CCD whose resolution is limited by pixel size is not used, the pattern light for focus detection is scanned on the substrate W to determine the focus or defocus of the imaging optical system 23, and the focus state can be accurately detected. In addition, since the rate of change of the amplitude ratio monotonically decreases with respect to the focus range AR determined by the master data stored in the memory, the direction of the focus deviation from the focus range AR can be reliably detected in the event of out-of-focus. On the other hand, since the light detection unit 28 is used in common with the exposure position detection, it is not necessary to provide a CCD dedicated for focus detection, and the cost can be reduced.

另外，圖案光通過複數個狹縫，並根據其相對移動量算出平均中心值，藉此，即使在發生光源振動和光感測器敏感度不均的情況中，仍可抑制其影響。此外，藉由複數個桿狀圖案通過複數個狹縫，擴大平均值的母數，更精確地量測振幅比。 In addition, the pattern light passes through a plurality of slits, and an average center value is calculated based on the relative movement amount, whereby the influence of the pattern light can be suppressed even when the vibration of the light source and the uneven sensitivity of the light sensor occur. In addition, a plurality of rod-shaped patterns are passed through a plurality of slits to expand the mother of the average value and more accurately measure the amplitude ratio.

焦點檢出用圖案列的桿狀圖案可不垂直於主掃描方向，與狹縫形成方向一致地決定圖案形狀，也可決定狹縫的主掃描方向寬度、圖案光的主掃描方向寬度以得到上述的連續光量分佈。關於光感測器，可對各掃描帶皆設置光感測器。 The rod pattern of the focus detection pattern row may not be perpendicular to the main scanning direction, and the pattern shape may be determined in accordance with the slit formation direction. The main scanning direction width of the slit and the main scanning direction width of the pattern light may be determined to obtain the above Continuous light distribution. As for the light sensor, a light sensor may be provided for each scanning band.

接著，用第10~13圖說明第2實施形態。在第2實施形態中，監測成像光學系統的解析性能。其以外的構成係與第1實施形態實質相同。 Next, a second embodiment will be described with reference to Figs. 10 to 13. In the second embodiment, the analysis performance of the imaging optical system is monitored. The other components are substantially the same as those of the first embodiment.

第10圖係表示維持解析性能的情況下的光量分佈與解析性能降低的情況下的光量分佈的圖。 Fig. 10 is a diagram showing a light amount distribution when the analysis performance is maintained and a light amount distribution when the analysis performance is reduced.

在成像光學系統23的解析性能高(沒有問題)情況下，如第1實施形態中所說明，接近解析性能上限的桿狀圖案光通過1個狹縫所得到的空間光量分佈GD是以其峰值為中心的高斯分佈，桿狀圖案邊緣部分的光量變化(傾斜)相對地大。儘管如此，若解析性能降低，空間光亮分佈GD1中，桿狀圖案邊緣部分的光量變化變緩和，並且，峰值光量降低，成為平緩的波形狀光量分佈。 When the analysis performance of the imaging optical system 23 is high (no problem), as explained in the first embodiment, the spatial light amount distribution GD obtained by passing the rod-shaped pattern light near the upper limit of the analysis performance through one slit is the peak value. The Gaussian distribution at the center has a relatively large change (inclination) in the amount of light at the edge portion of the rod-shaped pattern. However, if the analysis performance is degraded, the light amount change at the edge portion of the rod-shaped pattern in the spatial light distribution GD1 is reduced, and the peak light amount is reduced to a gentle wave-shaped light amount distribution.

結果，根據圖案列PT的連續空間光量分佈中，波形的山(峰值光量)與谷(底部光量)兩者與中心位置之間的距離變小。也就是說，空間光量分佈的振幅變小。因此，將所要求的最低解析性能所對應的振幅定義為作為標準之振幅，與第1實施形態一樣，藉由檢出空間光量分佈的振幅以計算振幅比，可監控解析性能。 As a result, in the continuous spatial light quantity distribution according to the pattern row PT, the distance between the mountain (peak light quantity) and valley (bottom light quantity) of the waveform and the center position becomes small. That is, the amplitude of the spatial light quantity distribution becomes small. Therefore, the amplitude corresponding to the required minimum analysis performance is defined as the standard amplitude. As in the first embodiment, the analysis performance can be monitored by detecting the amplitude of the spatial light quantity distribution to calculate the amplitude ratio.

第11圖係表示解析能力與振幅比之間的關係的圖形的示意圖。第12圖係表示作為標準之振幅的空間光量分佈的圖。 FIG. 11 is a schematic diagram showing a relationship between the analysis ability and the amplitude ratio. Fig. 12 is a diagram showing a spatial light quantity distribution with a standard amplitude.

第11圖中描繪表示解析能力與振幅比之間的對應關係的曲線CG。但是，表示第11圖的圖形橫軸的解析能力，係表示對於成像光學系統23每單位長度(1mm)可成像的直線數目。由於若解析性能降低則振幅減少，隨著振幅比的值變小則解析能力降低。因此，若所量測的振幅比大於作為界限(下限)的振幅比D0，則維持所要求的解析性能。 In FIG. 11, a curve CG showing a correspondence relationship between the analysis ability and the amplitude ratio is drawn. However, the analysis capability of the horizontal axis of the graph in FIG. 11 indicates the number of straight lines that can be imaged per unit length (1 mm) of the imaging optical system 23. When the analysis performance decreases, the amplitude decreases, and as the value of the amplitude ratio decreases, the analysis ability decreases. Therefore, if the measured amplitude ratio is larger than the amplitude ratio D0 as a limit (lower limit), the required analysis performance is maintained.

第12圖所示的空間光量分佈GD’表示連接所要求的解析性能界限所對應的1個桿狀圖案的空間光量分佈GD1、 GD2時所得到的光量分佈。對應至解析性能界限的空間光量分佈GD1、GD2的波形係根據曝光裝置的規格、成像光學系統23等的光學性能而定。 The spatial light quantity distribution GD 'shown in FIG. 12 represents the spatial light quantity distribution GD1 of a rod-shaped pattern corresponding to the required analytical performance limit. The amount of light distribution obtained at GD2. The waveforms of the spatial light quantity distributions GD1 and GD2 corresponding to the analysis performance limit are determined according to the specifications of the exposure device, the optical performance of the imaging optical system 23, and the like.

空間光量分佈GD’的振幅A0與解析性能為最高時的最大振幅B的比(A0/B)係定義為界限振幅比D0，若所檢出的振幅A與標準振幅B的比A/B為D0以上，可判斷為滿足所必須的解析性能。與界限振幅比D0以及曲線CG相關的資料係預先儲存於記憶體32。 The ratio (A0 / B) of the amplitude A0 of the spatial light distribution GD 'to the maximum amplitude B when the analytical performance is the highest is defined as the limit amplitude ratio D0. If the ratio A / B of the detected amplitude A to the standard amplitude B is Above D0, it can be judged that the required analysis performance is satisfied. Data related to the limit amplitude ratio D0 and the curve CG are stored in the memory 32 in advance.

第13圖係表示解析性能的監測處理的流程的圖。與第1實施形態一樣，在任意的時機(批次生產開始時，或者每經過預定時間時等等)進行處理。 FIG. 13 is a diagram showing a flow of monitoring processing of analysis performance. As in the first embodiment, processing is performed at an arbitrary timing (at the start of batch production, or every predetermined time, etc.).

控制器30，在移動平台12的同時，為了向遮光單元40照射圖案列PT，控制DMD驅動電路24(S201)。然後，根據自光感測器PD輸出的光量訊號，算出振幅比M(S202)，並判斷振幅比M是否為界限振幅比D0以上(S203)。當振幅比M未滿界限振幅比D0時，藉由警告音蜂鳴等將解析性能降低通知給操作者(S204)。 The controller 30 controls the DMD driving circuit 24 in order to irradiate the pattern row PT to the light shielding unit 40 while moving the stage 12 (S201). Then, the amplitude ratio M is calculated based on the light amount signal output from the light sensor PD (S202), and it is determined whether the amplitude ratio M is equal to or greater than the limit amplitude ratio D0 (S203). When the amplitude ratio M is less than the limit amplitude ratio D0, the operator is notified of a reduction in the analysis performance by a warning sound or the like (S204).

根據上述第2實施形態，在移動平台12的同時，藉由將桿狀圖案PL1~PL4所構成的圖案列PT投影至狹縫ST1~ST6形成的遮光單元40，自光感測器PD輸出光量訊號。然後，根據自光量訊號求得的振幅比M，判斷解析力是否低於界限解析力。 According to the second embodiment described above, when the platform 12 is moved, the pattern row PT formed by the rod patterns PL1 to PL4 is projected onto the light shielding unit 40 formed by the slits ST1 to ST6, and the light quantity is output from the light sensor PD. Signal. Then, based on the amplitude ratio M obtained from the light amount signal, it is determined whether the resolution is lower than the limit resolution.

在第1、第2實施形態中，藉由使圖案列的線/間隙寬度相等而將光量振幅的中心位置(平均光量)視為一定，雖 然聚焦狀態下的標準振幅係從平均光量與圖案非投影狀態的光量算出，但也可藉由此外的方法算出標準振幅，另外，即使在圖案列的線/間隙寬度不相等的情況下，也可求得振幅比。舉例而言，也可在移動光學系統或者基板的同時所進行的焦點調整中，算出聚焦狀態下或者具有解析力之狀態下的波形狀光量，並在基於光源輸出變動等的同時決定焦點檢出時的標準振幅。 In the first and second embodiments, the center position (average light amount) of the light amount amplitude is considered constant by making the line / gap widths of the pattern rows equal. Although the standard amplitude in the focused state is calculated from the average light amount and the light amount in the non-projected state of the pattern, the standard amplitude can also be calculated by other methods. In addition, even when the line / gap width of the pattern rows are not equal, The amplitude ratio can be obtained. For example, in the focus adjustment performed while moving the optical system or the substrate, the amount of wave-shaped light in the focused state or in the state with analytical power can be calculated, and the focus detection can be determined based on the fluctuation of the light source output, etc. Standard amplitude at time.

另外，也可在移動平台的同時不投影桿狀圖案列，而對CCD等影像感測器投影L/S圖案光，並從其空間光量分佈判斷聚焦狀態或解析性能的狀態。 In addition, it is also possible to project the L / S pattern light on an image sensor such as a CCD without moving the platform while projecting a rod-shaped pattern column, and judge the focus state or the analysis performance state from the spatial light quantity distribution.

接著，用第14~20圖說明第3實施形態。在第3實施形態中，檢出曝光區域整體的光量分佈，監測是否光量降低。 Next, a third embodiment will be described with reference to Figs. 14 to 20. In the third embodiment, the light amount distribution of the entire exposed area is detected, and it is monitored whether the light amount is decreased.

第3實施形態之曝光裝置，採用與如第1圖所示之第1實施形態相同的構成。但是，不設置稜鏡以及稜鏡驅動單元。 The exposure apparatus of the third embodiment has the same configuration as that of the first embodiment shown in FIG. However, 稜鏡 and 稜鏡 drive units are not provided.

為檢查是否沒有光學系統的劣化，在批次的間隔或曝光作業時間每經過預定時間時，進行光量量測。具體而言，在以一定速度移動平台12的同時，投影光量分佈檢出用的圖案光。控制器30，根據來自光檢出單元28的輸出訊號，判斷是否發生光量降低。 In order to check whether there is no deterioration of the optical system, light quantity measurement is performed every time a predetermined time elapses between the batch interval or the exposure operation time. Specifically, while moving the stage 12 at a constant speed, the pattern light for detecting the light amount distribution is projected. The controller 30 determines whether a reduction in light amount occurs based on an output signal from the light detection unit 28.

另外，為在正確的位置形成圖案，在曝光動作開始前進行與曝光開始位置相關的校正處理。具體而言，在以一定速度移動平台12的同時，投影位置檢出用的圖案光。控制 器30，根據傳送自演算單元27的位置資訊，校正曝光開始位置。 In addition, in order to form a pattern at a correct position, a correction process related to the exposure start position is performed before the exposure operation is started. Specifically, while moving the stage 12 at a constant speed, the pattern light for detecting the projection position is projected. control The controller 30 corrects the exposure start position according to the position information transmitted from the calculation unit 27.

以下，用第14~15圖說明聚焦狀態的檢出、監測。 The detection and monitoring of the focus state will be described below with reference to FIGS. 14 to 15.

第14圖係表示光量分佈量測用的圖案列與遮光單元的圖。 FIG. 14 is a diagram showing a pattern row and a light-shielding unit for measuring the light amount distribution.

光量分佈量測用的圖案列PT為分別具有圖案長度Ly的複數個桿狀圖案PL1、PL2、...沿著主掃描方向等間隔並排的圖案列(以下也稱為線與間隙(L/S)圖案)，平行於副掃描方向的各桿狀圖案係以間距PP等間隔並排。每個此處的桿狀圖案的寬度相當於沿著副掃描方向的1行微鏡的微小投影區域寬度。 The pattern rows PT for light quantity distribution measurement are a plurality of rod patterns PL1, PL2, ... each having a pattern length Ly, which are arranged side by side at regular intervals in the main scanning direction (hereinafter also referred to as lines and gaps (L / S) Patterns). The rod-shaped patterns parallel to the sub-scanning direction are arranged side by side at equal intervals PP. The width of each of the rod-shaped patterns here corresponds to the width of the micro-projection area of one row of micromirrors along the sub-scanning direction.

形成於遮光單元40的狹縫SL，具有比圖案列PT沿著副掃描方向的圖案長度Ly大的沿著副掃描方向的長度SLL。另外，狹縫SL，相對於圖案列PT的線方向(長度方向)，僅傾斜微小角度θ。在此，圖案列PT，係形成為相對於規定至上述平台12之X-Y座標系統的Y方向(副掃描方向)僅傾斜微小角度θ0(第3圖中未表示)。因此，狹縫SL相對於副掃描方向Y係僅傾斜θ±θ0。 The slit SL formed in the light shielding unit 40 has a length SLL in the sub-scanning direction that is larger than a pattern length Ly of the pattern row PT in the sub-scanning direction. The slit SL is inclined by a slight angle θ with respect to the line direction (longitudinal direction) of the pattern row PT. Here, the pattern row PT is formed so as to be inclined by a slight angle θ0 (not shown in FIG. 3) with respect to the Y direction (sub-scanning direction) of the X-Y coordinate system defined to the platform 12. Therefore, the slit SL is inclined with respect to the sub-scanning direction Y by only θ ± θ0.

在此，配置於狹縫SL下方的光感測器PD，係由具有1個受光面PS的1個光二極體所構成，僅接受通過具有桿狀細長區域(測光區域)PDS的狹縫SL的光。也就是說，在光感測器PD的受光面PS的整體區域之中，透過狹縫SL的光係入射至一部分的區域。另外，光感測器PD，為使透過狹縫SL的光全部到達光感測器PD，其沿著副掃描方向的長度SB 比圖案長度Ly長，並具有比狹縫SL之寬度大的光感測器寬度PDW。另一方面，如下所述，狹縫寬度SLB比各桿狀圖案的寬度小。 Here, the photo sensor PD disposed below the slit SL is composed of one photodiode having one light-receiving surface PS, and only passes through the slit SL having a rod-shaped elongated region (photometric region) PDS. Light. That is, in the entire area of the light-receiving surface PS of the photo sensor PD, the light passing through the slit SL enters a part of the area. In addition, the photo sensor PD has a length SB along the sub-scanning direction so that all the light transmitted through the slit SL reaches the photo sensor PD. The photo sensor width PDW is longer than the pattern length Ly and has a width larger than the width of the slit SL. On the other hand, as described below, the slit width SLB is smaller than the width of each bar-shaped pattern.

圖案列PT的間距PP係定為比狹縫SL沿著主掃描方向的佔有長度B大。在此，佔有長度B表示狹縫SL的任意點T1(在此為與圖案列PT一致的狹縫位置)與在副掃描方向上距離Ly之點T2之間沿著主掃描方向所佔據的長度(投射時的長度)，由於傾斜角度θ微小，可表示為主掃描方向佔有長度B≒Lytanθ。 The pitch PP of the pattern row PT is set to be longer than the occupation length B of the slit SL in the main scanning direction. Here, the occupation length B indicates the length occupied by an arbitrary point T1 of the slit SL (here, the slit position corresponding to the pattern row PT) and a point T2 at a distance Ly in the sub-scanning direction along the main scanning direction. (Length in projection) Since the tilt angle θ is small, the length B 表示 Lytanθ in the main scanning direction can be represented.

如此一來，藉由將圖案間距PP定為比狹縫SL主掃描方向的佔有長度B大，圖案列PT通過狹縫SL時，從1個桿狀圖案開始通過狹縫SL，在通過完成之前，下一個桿狀圖案不會開始通過狹縫SL，也就是說，線感測器之光感測器PD係時序地一個接一個依序接受桿狀圖案光。 In this way, by setting the pattern pitch PP to be larger than the occupation length B in the main scanning direction of the slit SL, when the pattern row PT passes through the slit SL, the pattern SL starts to pass through the slit SL from one rod pattern, and before the passage is completed , The next rod pattern will not start to pass through the slit SL, that is, the light sensor PD of the line sensor sequentially receives the rod pattern light one by one in sequence.

第15A~15D圖係表示1個桿狀圖案PL1通過狹縫SL之過程的圖。第16圖係1個桿狀圖案PL1通過狹縫SL時所取得的沿著副掃描方向的光量分佈。另外，為說明起見，係誇張地描繪狹縫SL相對於圖案列PT的傾斜角度。 15A to 15D are diagrams showing a process in which one rod pattern PL1 passes through the slit SL. FIG. 16 is a light amount distribution along the sub-scanning direction obtained when one rod pattern PL1 passes through the slit SL. In addition, for the sake of explanation, the inclination angle of the slit SL with respect to the pattern row PT is exaggeratedly depicted.

由於狹縫SL相對於桿狀圖案PL1傾斜，桿狀圖案PL1其中一長度方向側LT1在其端部EL開始與狹縫SL相交(參照第15A圖)。隨著桿狀圖案PL1相對移動，桿狀圖案PL1與狹縫SL的相交範圍R變大(參照第15B圖)，變成狹縫SL與桿狀圖案PL1的長度方向側LT1、LT2相交。 Since the slit SL is inclined with respect to the rod-shaped pattern PL1, one of the longitudinal sides LT1 of the rod-shaped pattern PL1 starts to intersect with the slit SL at its end EL (see FIG. 15A). As the rod pattern PL1 moves relatively, the intersection range R between the rod pattern PL1 and the slit SL becomes larger (see FIG. 15B), and the slit SL intersects with the longitudinal sides LT1 and LT2 of the rod pattern PL1.

持續狹縫SL與桿狀圖案PL1的長度方向側LT1、 LT2相交的狀態之後(參照第15C圖)，移轉至僅長度方向側LT2與桿狀圖案PL相交的階段，最後，桿狀圖案PL1整體超出狹縫SL(參照第15D圖)。 Lengthwise sides LT1 of the continuous slit SL and the rod pattern PL1 After the state where LT2 intersects (refer to FIG. 15C), it moves to a stage where only the longitudinal side LT2 intersects with the rod pattern PL, and finally, the rod pattern PL1 as a whole exceeds the slit SL (refer to FIG. 15D).

第16圖中係表示桿狀圖案PL1通過狹縫SL時所檢出的沿著副掃描方向的光量分佈。線感測器之光感測器PD，雖然時序地檢出光量，但如上所述，在1個桿狀圖案PL1與狹縫SL的相交開始與相交結束之間，相鄰的桿狀圖案PL2不會與狹縫SL相交。 FIG. 16 shows the light amount distribution in the sub-scanning direction detected when the rod-shaped pattern PL1 passes through the slit SL. Although the light sensor PD of the line sensor sequentially detects the light amount, as described above, between the beginning and end of the intersection of one rod pattern PL1 and the slit SL, the adjacent rod pattern PL2 Does not intersect the slit SL.

因此，光感測器PD時序地檢出的1個桿狀圖案的光量分佈，相當於沿著副掃描方向的光量分佈。第16圖的(A)~(D)分別表示第15A~15D圖所示的位置下桿狀圖案PL1當時的光量。 Therefore, the light amount distribution of one rod-shaped pattern detected by the light sensor PD in a time series corresponds to the light amount distribution along the sub-scanning direction. (A)-(D) of FIG. 16 show the light amount at the time of the rod pattern PL1 at the positions shown in FIGS. 15A-D.

第17圖係表示與光感測器的光量檢出時間間隔一致的狹縫的移動間距的圖。 FIG. 17 is a diagram showing a moving pitch of a slit in accordance with a light amount detection time interval of a photo sensor.

若每次狹縫SL沿著主掃描方向移動移動間距d時光量在光感測器PD中檢出，則量測長度L(=Lx/tanθ)沿著副掃描方向移動間距P(=d/tanθ)。但是，量測長度L係表示光量在光感測器PD中檢出所沿著副掃描方向的狹縫長。 If the light amount is detected in the light sensor PD each time the slit SL moves along the main scanning direction by the moving distance d, the measurement length L (= Lx / tanθ) moves along the sub-scanning direction by the distance P (= d / tanθ). However, the measurement length L indicates the length of the slit along the sub-scanning direction in which the light amount is detected in the photo sensor PD.

在此，桿狀圖案PL1的寬度Lx相較於沿著主掃描方向的移動間距d越充分大，則量測長度L相對於沿著副掃描方向的間距P越充分長(L>>P)。由於間距P表示沿著副掃描方向的解析能力，間距P比1個微鏡微小投影區域尺寸(單元尺寸)小。 Here, as the width Lx of the rod pattern PL1 is sufficiently larger than the moving pitch d in the main scanning direction, the measurement length L is sufficiently longer than the pitch P in the sub-scanning direction (L >> P) . Since the pitch P represents the resolution in the sub-scanning direction, the pitch P is smaller than the size (unit size) of the microprojection area of one micromirror.

結果，當每移動間距d檢出的光量分佈被視為沿 著副掃描方向的光量分佈時，其光量變化係以單元尺寸以下的變化表示，光量分佈曲線變得平滑。也就是說，可得到第16圖所示的沒有階差的光量分佈曲線。每次桿狀圖案依序通過狹縫SL時檢出沿著副掃描方向的光量分佈的結果，可得到對應曝光區域EA整體的光量分佈。 As a result, the light quantity distribution detected at each moving interval d is considered along the When the light quantity distribution in the sub-scanning direction is changed, the light quantity change is expressed as a change below the cell size, and the light quantity distribution curve becomes smooth. That is, a light quantity distribution curve without a step difference as shown in FIG. 16 can be obtained. As a result of detecting the light amount distribution along the sub-scanning direction each time the rod-shaped pattern sequentially passes through the slit SL, the light amount distribution corresponding to the entire exposure area EA can be obtained.

第18圖係表示重疊對應各桿狀圖案的光量分佈的圖。第19圖係3維表示對應曝光區域整體的光量分佈的圖。 Fig. 18 is a diagram showing light quantity distributions corresponding to respective rod-shaped patterns superimposed. FIG. 19 is a three-dimensional view showing a light amount distribution corresponding to the entire exposed area.

在第19圖中表示對應曝光區域整體的光量分佈LG。在此，周圍附近沒有發生光量減少，但在中心部分光量減少。如第18圖所示，在曝光區域周圍的光量分佈DPL1中檢出最大光量MM而中心附近的光量分佈DPLm中檢出最小光量ML的情況下，可根據其光量比(ML/MM)檢知光學系統等的劣化。但是，對於光量檢出，係以檢出中的有效範圍BE為對象算出光量比。 FIG. 19 shows a light amount distribution LG corresponding to the entire exposed area. Here, no decrease in light amount occurred in the vicinity, but a decrease in light amount in the center portion. As shown in FIG. 18, when the maximum light amount MM is detected in the light amount distribution DPL1 around the exposure area and the minimum light amount ML is detected in the light amount distribution DPLm near the center, it can be detected based on the light amount ratio (ML / MM). Deterioration of optical systems and the like. However, for the light amount detection, the light amount ratio is calculated by using the effective range BE during detection as an object.

第20圖係表示光量分佈量測與警告處理的流程圖。在此，每預定的操作時間即執行。 Fig. 20 is a flowchart showing light quantity distribution measurement and warning processing. Here, it is executed every predetermined operation time.

在對狹縫SL相對移動曝光區域的同時，投影圖案列PT，並藉由光感測器PD檢出光量(S301)。然後，根據來自光感測器PD的輸出訊號，算出光量比。並且，連同光量比的算出，作成3維的光量分佈資料，並保存於未圖示的記憶體等之中(S302)。 While the exposure area is relatively moved to the slit SL, the pattern line PT is projected, and the light amount is detected by the light sensor PD (S301). Then, the light quantity ratio is calculated based on the output signal from the light sensor PD. In addition to the calculation of the light amount ratio, three-dimensional light amount distribution data is created and stored in a memory (not shown) (S302).

若光量比在預先設定的閾值以下，在例如操作畫面上藉由警告顯示等通知光量降低(S303、S304)。此時，也可在生產管理用的檔案中紀錄表明此結果的情報。另外，將藉由 演算處理所取得的3維光量分佈資料與部件沒有劣化的初期光量分佈資料相比較，也可判斷是否發生光量降低。 If the light amount ratio is below a preset threshold, the light amount is notified to be reduced, for example, by a warning display on the operation screen (S303, S304). At this time, information indicating this result may be recorded in a file for production management. In addition, by It is also possible to determine whether or not a reduction in light amount has occurred by comparing the three-dimensional light amount distribution data obtained by the calculation process with the initial light amount distribution data in which the component has not deteriorated.

因此，根據第3實施形態，曝光裝置10的平台12中，在光感測器PD上方設置形成狹縫SL的光檢出單元28。然後，在相對於副掃描方向傾斜狹縫SL的狀態下投影圖案列PT，並通過狹縫SL。此時，圖案列PT的間距PP係定為比狹縫SL沿著主掃描方向的佔有長度B小。 Therefore, according to the third embodiment, the stage 12 of the exposure apparatus 10 is provided with a light detection unit 28 forming a slit SL above the photo sensor PD. Then, the pattern row PT is projected while the slit SL is inclined with respect to the sub-scanning direction, and passes through the slit SL. At this time, the pitch PP of the pattern row PT is set smaller than the occupation length B of the slit SL in the main scanning direction.

圖案列PT通過狹縫SL期間，各桿狀圖案PL1、PL2...一個一個依序替換的同時被投影至光感測器PD。1個桿狀圖案通過狹縫SL期間，下一個圖案不會開始通過狹縫SL。然後，藉由在光感測器PD中依微小角度θ移動其投影區域，可檢出沿著副掃描方向的光量分佈，而可獲得曝光區域整體的光量分佈。 While the pattern row PT passes through the slit SL, each of the rod-shaped patterns PL1, PL2, ... is sequentially replaced while being projected onto the light sensor PD. While one rod-shaped pattern passes through the slit SL, the next pattern does not start to pass through the slit SL. Then, by moving the projection area of the light sensor PD by a slight angle θ, the light quantity distribution along the sub-scanning direction can be detected, and the light quantity distribution of the entire exposed area can be obtained.

為形成曝光區域的光量分佈，由於曝光區域的狹縫通過時各桿狀圖案的光全部受光為必要，藉由將傾斜角度定為曝光區域的對角線角度以下，可實現曝光區域的光量分佈量測。舉例而言，若根據視頻規格等光學調變單元陣列(微鏡陣列)的垂直水平尺寸為4：3，傾斜角度θ可定為37°以下。另外，若光學調變單元陣列的垂直水平尺寸為16：9，傾斜角度θ可定為30°以下。 In order to form the light amount distribution of the exposed area, it is necessary to receive all the light of each rod pattern when the slits of the exposed area pass. By setting the tilt angle to be below the diagonal angle of the exposed area, the light amount distribution of the exposed area can be realized. Measure. For example, if the vertical and horizontal size of the optical modulation unit array (micromirror array) is 4: 3 according to the video specifications and the like, the tilt angle θ can be set to 37 ° or less. In addition, if the vertical and horizontal size of the optical modulation unit array is 16: 9, the tilt angle θ can be set to 30 ° or less.

此外，若以微小角度傾斜地相對移動曝光區域，其角度為微小。因此，藉由將相對於描繪工作台所規定之副掃描方向的狹縫傾斜角度定為37°以下，可求得類似的光量分佈。 In addition, if the exposure area is relatively moved obliquely at a slight angle, the angle is small. Therefore, by setting the tilt angle of the slit with respect to the sub-scanning direction prescribed by the drawing table to be 37 ° or less, a similar light amount distribution can be obtained.

雖然相對於圖案列PT的狹縫SL傾斜角度θ可設 定為不同的角度，但當考慮精確度層面時，希望盡可能地增加L/S圖案的圖案陣列數目。此意味著，希望以微鏡的1行投影各桿狀圖案。在此情況下，由於圖案列PT的寬度等受微鏡的微小投影區域(單元尺寸)等影響，為了滿足B<PP，可定為預定的傾斜角度以下。 Although the inclination angle θ of the slit SL with respect to the pattern row PT can be set Different angles are set, but when considering the level of accuracy, it is desirable to increase the number of pattern arrays of the L / S pattern as much as possible. This means that it is desirable to project each rod pattern in one line of the micromirror. In this case, since the width of the pattern row PT and the like are affected by the micro-projection area (cell size) of the micromirror, etc., in order to satisfy B <PP, it may be set to a predetermined tilt angle or less.

另一方面，在滿足B<PP的範圍內，使θ盡可能大者可提高解析能力。另外，若隨著量測長度L變長而光量上升/下降區域的長度變長，則對應地檢出有效範圍BE會變窄。為了盡可能使有效範圍BE變廣，較佳為使θ盡可能大。 On the other hand, in the range satisfying B <PP, making θ as large as possible can improve the analysis ability. In addition, if the length of the light amount rising / falling area becomes longer as the measurement length L becomes longer, the detection effective range BE becomes narrower accordingly. In order to make the effective range BE as wide as possible, it is preferable to make θ as large as possible.

作為一例，若使用由根據XGA規格的1024×768的微鏡組成的DMD(線方向(line direction)上1024像素)，線間距PP可藉由L/S圖案的線數目決定。考慮到光量分佈資料的精確度層面，當設定16條以上的線數目時，線16條時的間距PP為768/15=51像素，由於必須要滿足B(=1024tanθ)<PP(=51)，傾斜角度θ定為比2.8°小。由於Y方向的解析能力P係以d/tanθ表示，當移動間距d=1μm時，θ=2.8°時解析能力P=20μm。 As an example, if a DMD (1024 pixels in the line direction) composed of 1024 × 768 micromirrors according to the XGA standard is used, the line pitch PP can be determined by the number of lines of the L / S pattern. Considering the accuracy level of the light quantity distribution data, when setting more than 16 lines, the pitch PP at 16 lines is 768/15 = 51 pixels, because it must meet B (= 1024tanθ) <PP (= 51) , The inclination angle θ is set to be smaller than 2.8 °. Since the resolution P in the Y direction is expressed as d / tanθ, when the moving distance d = 1 μm, the resolution P = 20 μm when θ = 2.8 °.

另一方面，在使檢出有效範圍BE超過圖案長度Ly的90%(換句話說，使L為Ly的5%以下)的情況下，當圖案光的線的寬度Lx為1像素，由於L=Lx/tanθ<Ly×0.05，導出tanθ>1/51.2。也就是說，傾斜角度θ定為比1.2°大的角度。在此情況下，θ=1.2°下分解能力P=48μm。 On the other hand, when the detection effective range BE exceeds 90% of the pattern length Ly (in other words, L is 5% or less of Ly), when the width Lx of the line of the pattern light is 1 pixel, since L = Lx / tanθ <Ly × 0.05, and tanθ> 1 / 51.2 is derived. That is, the inclination angle θ is set to an angle larger than 1.2 °. In this case, the resolution P = 48 μm at θ = 1.2 °.

根據上述，可在1.2°<θ<2.8°的範圍中決定狹縫SL與圖案列PT之間的角度θ，更佳為在2.0°<θ<2.8°的範圍中決 定θ。另外，在具有曝光區域的傾斜角度θ0的情況下，若傾斜至與狹縫相同側則減算其量，若與傾斜至與狹縫相反側則可加算其量。 According to the above, the angle θ between the slit SL and the pattern row PT can be determined in the range of 1.2 ° <θ <2.8 °, and more preferably in the range of 2.0 ° <θ <2.8 ° 定 θ. In the case where there is an inclination angle θ0 of the exposure area, the amount is subtracted if it is inclined to the same side as the slit, and the amount is added if it is inclined to the opposite side to the slit.

此外，關於光感測器PD，也可由上述沿著長度方向的細長光二極體以外的感測器構成，可為具有桿狀圖案受光可能之受光面感測器的光感測器。藉由以光感測器PD形狀設置狹縫的遮光單元以外的構成，也可檢出光量分佈。另外，投影圖案也可適用上述圖案以外的L/S圖案。為依序量測L/S圖案的各線狀圖案的光量，藉由決定L/S圖案光的間距，可量測曝光區域整體的光量分佈。另外，在曝光頭為複數的情況下，可對各曝光頭形成狹縫。 In addition, the photo sensor PD may be constituted by a sensor other than the above-mentioned elongated photodiode in the longitudinal direction, and may be a photo sensor having a light-receiving surface sensor capable of receiving light in a rod-like pattern. The light quantity distribution can also be detected by a configuration other than the light shielding unit in which the slit is formed in the shape of the light sensor PD. In addition, the projection pattern may be applied to an L / S pattern other than the above pattern. In order to sequentially measure the light amount of each linear pattern of the L / S pattern, the light amount distribution of the entire exposed area can be measured by determining the interval of the L / S pattern light. When the number of exposure heads is plural, a slit may be formed in each exposure head.

測光單元的構成並不限定於上述構成，舉例而言，可構成為遮光單元和與光感測器一體成形的測光單元可拆卸地安裝至曝光裝置或者一體設置。設置具有可接受通過相對於線圖案傾斜的細長(於長度方向延伸)測光區域的光的受光區域的光感測器，可構成為圖案光通過時光入射至受光區域整體中對應至測光區域的區域。 The configuration of the photometric unit is not limited to the above-mentioned configuration. For example, the photometric unit may be configured such that the light-shielding unit and the photometric unit integrally formed with the light sensor are detachably attached to the exposure device or provided integrally. A light sensor having a light-receiving area that can receive light passing through an elongated (lengthwise) light-measuring area inclined with respect to a line pattern can be configured so that the pattern light passes through the entire light-receiving area and corresponds to the light-measuring area when the light passes therethrough. .

另外，也可求得光量差而非光量比，在差為預定閾值以上時判斷發生光學系統的劣化。也可藉由光量比、光量差以外的參數檢出光量變化。 In addition, it is also possible to obtain a light amount difference instead of a light amount ratio, and it may be determined that degradation of the optical system occurs when the difference is equal to or more than a predetermined threshold. Changes in the amount of light can also be detected using parameters other than the light amount ratio and the light amount difference.

Claims (13)

一種曝光裝置，其特徵為包括：複數個光學調變單元排列成矩陣形狀的光學調變單元陣列；將上述光學調變單元陣列的曝光區域相對於被描繪體沿著主掃描方向相對移動的掃描單元；根據對應於上述曝光區域之相對位置的圖案資料控制上述複數個光學調變單元的曝光控制單元；將來自上述光學調變單元陣列的圖案光成像至上述被描繪體的描繪面的成像光學系統；沿著上述描繪面形成至少1個狹縫的遮光單元；接受透過上述狹縫的光的測光單元；以及根據上述測光單元的輸出檢出聚焦狀態的聚焦檢出單元；其中，上述曝光控制單元，在上述曝光區域對上述遮光單元相對移動的時候，投影線與間隙(L/S)圖案光；其中，上述聚焦檢出單元，根據藉由L/S圖案光的投影所檢出的波形狀光量的振幅以及在聚焦範圍中時的標準振幅，檢出上述描繪面是否在聚焦範圍中。An exposure device, comprising: an array of optical modulation units in which a plurality of optical modulation units are arranged in a matrix shape; and scanning in which the exposure area of the above-mentioned optical modulation unit array is relatively moved in the main scanning direction with respect to the object being drawn An exposure control unit that controls the plurality of optical modulation units according to the pattern data corresponding to the relative positions of the exposure areas; an imaging optic that images the pattern light from the optical modulation unit array onto the drawing surface of the object to be drawn A system; a light-shielding unit that forms at least one slit along the drawing surface; a photometry unit that receives light passing through the slit; and a focus detection unit that detects a focus state based on the output of the photometry unit; wherein the exposure control A unit that projects the line and the gap (L / S) pattern light when the exposure area moves relative to the light-shielding unit; wherein the focus detection unit detects the wave based on the wave detected by the projection of the L / S pattern light The amplitude of the shape light amount and the standard amplitude when it is in the focus range, and it is detected whether the drawing surface is in the focus range . 如申請專利範圍第1項所述之曝光裝置，其中，上述聚焦檢出單元，根據相當於光量振幅與標準振幅之比的振幅比，判斷是否在聚焦範圍中。The exposure apparatus according to item 1 of the patent application range, wherein the focus detection unit determines whether or not it is in the focus range based on an amplitude ratio corresponding to a ratio of a light amount amplitude to a standard amplitude. 如申請專利範圍第2項所述之曝光裝置，其中，上述聚焦檢出單元，根據上述振幅比與上述成像光學系統的焦點位置之間的對應關係，判斷是否在聚焦範圍內。The exposure device according to item 2 of the scope of patent application, wherein the focus detection unit determines whether it is within a focus range based on a correspondence relationship between the amplitude ratio and a focal position of the imaging optical system. 如申請專利範圍第1至3項中任一項所述之曝光裝置，其中，上述聚焦檢出單元，根據L/S圖案光的平均光量與沒投影L/S圖案光時的基本光量，算出標準振幅。The exposure device according to any one of claims 1 to 3, wherein the focus detection unit calculates based on the average light amount of the L / S pattern light and the basic light amount when the L / S pattern light is not projected. Standard amplitude. 如申請專利範圍第4項所述之曝光裝置，其中，上述遮光單元具有平均光量量測用之開口單元，上述測光單元具有接受通過上述平均光量量測用之開口單元L/S圖案光的平均光量量測用受光單元。The exposure device according to item 4 of the scope of patent application, wherein the light shielding unit has an opening unit for measuring the average light amount, and the light measuring unit has an average of receiving the L / S pattern light passing through the opening unit for the average light amount measurement. Light receiving unit for light quantity measurement. 一種曝光裝置，其特徵為包括：複數個光學調變單元排列成矩陣形狀的光學調變單元陣列；將上述光學調變單元陣列的曝光區域相對於被描繪體沿著主掃描方向相對移動的掃描單元；根據對應於上述曝光區域之相對位置的圖案資料控制上述複數個光學調變單元的曝光控制單元；將來自上述光學調變單元陣列的圖案光成像至上述被描繪體的描繪面的成像光學系統；沿著上述描繪面形成至少1個狹縫的遮光單元；接受透過上述狹縫的光的測光單元；以及根據來自上述測光單元的輸出檢出上述成像光學系統的解析能力的解析能力檢出單元；其中，上述曝光控制單元，在上述曝光區域對上述遮光單元相對移動的時候，投影線與間隙(L/S)圖案光；其中，上述解析能力檢出單元，根據藉由L/S圖案光的投影所檢出的波形狀光量的振幅以及具有預定的界限解析能力以上的解析能力時的標準振幅，檢出解析能力是否比界限解析能力低。An exposure device, comprising: an array of optical modulation units in which a plurality of optical modulation units are arranged in a matrix shape; and scanning in which the exposure area of the above-mentioned optical modulation unit array is relatively moved in the main scanning direction with respect to the object being drawn An exposure control unit that controls the plurality of optical modulation units according to the pattern data corresponding to the relative positions of the exposure areas; an imaging optic that images the pattern light from the optical modulation unit array onto the drawing surface of the object to be drawn A light-shielding unit that forms at least one slit along the drawing surface; a light-measuring unit that receives light passing through the slit; and an analysis capability detection that detects an analysis capability of the imaging optical system based on an output from the light-measurement unit Unit; wherein, the exposure control unit, when the exposure area is relatively moved to the light-shielding unit, projects a line of light and a gap (L / S) pattern light; wherein the resolution detection unit is based on the L / S pattern The amplitude of the wave shape light amount detected by the projection of the light and has a predetermined limit analysis ability to Standard amplitude at the time resolving power, the resolving power of detection capability is lower than the limit resolution. 如申請專利範圍第6項所述之曝光裝置，其中，上述解析能力檢出單元，根據相當於所檢出之振幅與標準振幅之比的振幅比，判斷解析能力是否比界限解析能力低。The exposure apparatus according to item 6 of the scope of patent application, wherein the analysis capability detection unit determines whether the analysis capability is lower than the limit analysis capability based on an amplitude ratio corresponding to a ratio of a detected amplitude to a standard amplitude. 如申請專利範圍第7項所述之曝光裝置，其中，上述解析能力檢出單元，根據振幅比與上述成像光學系統的解析能力之間的對應關係，判斷解析能力是否比界限解析能力低。The exposure apparatus according to item 7 of the scope of patent application, wherein the resolution detection unit determines whether the resolution is lower than the limit resolution based on a correspondence between an amplitude ratio and the resolution of the imaging optical system. 一種曝光裝置，其特徵為包括：複數個光學調變單元排列成矩陣形狀的光學調變單元陣列；將上述光學調變單元陣列的曝光區域相對於被描繪體沿著主掃描方向相對移動的掃描單元；控制上述複數個光學調變單元，將沿著主掃描方向排列的線與間隙(L/S)圖案的光投影至上述被描繪體的曝光控制單元；接受通過相對於L/S圖案之線方向傾斜的細長的測光區域的光的測光單元；以及根據L/S圖案對上述測光區域相對移動時來自上述測光單元的輸出，檢出曝光區域的光量分佈的光量檢出單元；其中，L/S圖案的間距係決定為使L/S圖案的各線狀圖案的光量依序被量測。An exposure device, comprising: an array of optical modulation units in which a plurality of optical modulation units are arranged in a matrix shape; and scanning in which the exposure area of the above-mentioned optical modulation unit array is relatively moved in the main scanning direction with respect to the object being drawn Unit; controls the plurality of optical modulation units to project light of lines and gaps (L / S) patterns aligned along the main scanning direction onto the exposure control unit of the subject; A light metering unit for light in an elongated metering area inclined in a line direction; and a light amount detection unit that detects a light amount distribution of an exposure area when an output from the light metering unit is relatively moved according to an L / S pattern to the light metering area; The pitch of the / S pattern is determined such that the light amount of each linear pattern of the L / S pattern is sequentially measured. 如申請專利範圍第9項所述之曝光裝置，其中，上述測光區域相對於線方向傾斜的角度滿足下列式子：Lytanθ<PP，其中，Ly表示L/S圖案沿著副掃描方向的長度，θ表示相對於上述測光區域的線方向的傾斜角度，PP表示L/S圖案的間距。The exposure device according to item 9 of the scope of patent application, wherein the angle at which the photometric area is inclined with respect to the line direction satisfies the following formula: Lytanθ <PP, where Ly represents the length of the L / S pattern along the sub-scanning direction, θ represents the inclination angle with respect to the line direction of the photometric area, and PP represents the pitch of the L / S pattern. 如申請專利範圍第10項所述之曝光裝置，其中，上述測光區域相對於線方向傾斜的角度滿足下列式子：θ≦37°。The exposure apparatus according to item 10 of the scope of application for a patent, wherein the angle at which the photometric region is inclined with respect to the line direction satisfies the following formula: θ ≦ 37 °. 如申請專利範圍第11項所述之曝光裝置，其中，上述測光區域相對於線方向傾斜的角度滿足下列式子：1.2°<θ<2.8°。The exposure device according to item 11 of the scope of patent application, wherein the angle of the above-mentioned photometric area inclined with respect to the line direction satisfies the following formula: 1.2 ° <θ <2.8 °. 如申請專利範圍第9至12項中任一項所述之曝光裝置，其中，上述光量檢出單元作成曝光區域的光量分佈圖。The exposure device according to any one of claims 9 to 12, in which the above-mentioned light quantity detection unit creates a light quantity distribution map of the exposure area.