201118366 六、發明說明： 【發明所屬之技術領域】 本發明係關於可用於（例如）藉由微影技術的器件之製造 中的檢測方法，且係關於使用微影技術來製造器件之方 法。詳言之，本發明係關於散射計方法及裝置。 【先前技術】 微影裝置為將所要圖案施加至基板上（通常施加至基板 之目標部分上）的機器。微影裝置可用於（例如）積體電路 (ic)之製造中。在彼情況下，圖案化器件（其或者被稱作光 罩或主光罩）可用以產生待形成於1C之個別層上的電路圖 案可將此圖案轉印至基板（例如，矽晶圓）上之目標部分 (例如，包含晶粒之一部分、一個晶粒或若干晶粒）上。圖 案之轉印通常係經由成像至提供於基板上之輻射敏感材料 (抗蝕劑）層上。一般而言，單一基板將含有經順次圖案化 之鄰近目標部分的網路。已知微影裝置包括：所謂的步進 器，其中藉由一次性將整個圖案曝光至目標部分上來照射 每—目標部分；及所謂的掃描器，其令藉由在給定方向 (「掃描」方向）上經由輻射光束而掃描圖案同時平行或反 平行於此方向而同步地掃描基板來照射每一目標部分。亦 有可能藉由將圖案壓印至基板上而將圖案自圖案化器件轉 印至基板。 為了監視微影處理程序，有必要量測經圖案化基板之參 數’例如’形成於基板中或基板上之順次層之間的疊對誤 差。存在用於進行在微影處理程序中所形成之顯微結構之 145019.doc 201118366 直測的各種技術，包括掃描電子顯微鏡及各種專門工具之 使用。-種形式之專門檢測工具為散射計，其令將輻射光 束引導至基板之表面上之目標上’且量測經散射光束或铿 反射光束之屬Ή由比較光束在其已藉由基板反射或散 射之前與之後的輕，可判定基板之屬性。此可（例如）藉 由比較經反射光束與儲存於與已知基板屬性相關聯之已二 量測庫中的資料而進行。吾人已知兩種主要類型之散射 計。分光散射計將寬頻帶輻射光束引導至基板上，且量測 經散射成特定窄角範圍之輻射的光譜（料波長之函數的 強度）。㈣析散射計使料色輻射光束且量測經散射輻 射之作為角度之函數的強度。 為了量測光譜，必須將經反射輻射光束聚焦於散射計偵 測器上。由於難以使用用於散射計量測之寬頻帶輻射光束 來判定接物鏡在目標上方之最佳高度以達成最佳焦點故 已知的係使用具有自有窄頻帶輻射源之專門焦點感測器來 執行必要量測。接著使用經量測值來控制接物鏡之位置以 使目標保持於最佳焦點巾’且判定散射計中用於參考及校 準之基準的高度。然、而’本巾請案之發明人已認識到在該 配f中存在以下問題：如藉由焦點感測器所量測的接物鏡 之最佳位置可能不精確地匹配於用於散射計偵測器之最佳 焦點位置。 【發明内容】 需要提供一種使用散射計之檢測方法，其中至少減輕此 問題。 145019.doc 201118366 根據本發明之第—態樣，提供一種經組態以量測基板之 屬性的散射計，其包含： 聚焦配置； 焦點感測器； 焦點控制器，其係回應於該焦點感測器以提供有效於使 致動器配置在調整程序㈣調整為$焦輻#光束所需要的 该聚焦配置與該基板之相對位置的控制信號；及 焦點偏移配置，其經調適以將偏移提供至由該聚焦配置 所產生之焦點，以補償在該調整程序期間該散射計之聚焦 與在使用該散射計期間該散射計之聚焦之間的差。 根據本發明H樣，提供—種用於使用散射計來量 測基板之屬性的散射量測方法，其包含： 調整程序，其包含： 判定為聚焦輕射光束所需要的該聚焦配置與該基板之相 對位置； 提供表示該聚焦配置與該基板之該等相對位置的控制信 號；及 取决於③等控制信號而調整該聚焦配置與該基板之該等 相對位置以引起該聚焦； 及 將偏移提供至由該聚焦配置所產生之焦點，以補償在該 調整程序期間該散射計之聚焦與在使用該散射計期間該散 射計之聚焦之間的差。 根據本發明之第三態樣，提供一種器件製造方法，其包 145019.doc 201118366 含： 使用微影裝置以在基板上形成圖案；及 使用散射計來判定與由該微影裝置所印刷之該圖案之參 數相關的值，其包括’· 調整程序，其包含： 判定為聚焦輻射光束所需要的該聚焦配置與該基板之相 對位置； 提供表示該聚焦配置與該基板之該等相對位置的控制信 號；及 取決於該等控制信號而調整該聚焦配置與該基板之該等 相對位置以引起該聚焦； 及 將偏移提供至由該聚焦配置所產生之焦點，以補償在該 調整程序期間該散射計之聚焦與在使用該散射計期間該散 射計之聚焦之間的差。 【實施方式】 現將參看隨附示意性圖式而僅藉由實例來描述本發明之 貫施例’在該等圖式t，對應參考符號指示對應部分。 圖1不意性地描繪微影裝置。裝置包含： -照明系統(照明器)比，其經組態以調節輻射光束B(例 如，UV輪射或輻射）； ^支撐結構（例如，光罩台）MT，其經建構以支樓圖案化 如’光罩）MA，且連接至經組態以根據某些參數來 ,丨定位圖案化器件之第一***PM; 145019.doc 201118366 -基板台（例如，晶圓台）WT，其經建構以固持基板（例 如，塗布抗且連接至肋態以根據某些參 數來準確地定位基板之第二***PW;及201118366 VI. Description of the Invention: TECHNICAL FIELD OF THE INVENTION The present invention relates to a detection method that can be used, for example, in the manufacture of devices by lithography, and is directed to a method of fabricating a device using lithography. In particular, the present invention relates to scatterometer methods and apparatus. [Prior Art] A lithography apparatus is a machine that applies a desired pattern onto a substrate (usually applied to a target portion of the substrate). The lithography apparatus can be used, for example, in the manufacture of integrated circuits (ic). In this case, a patterned device (which may be referred to as a reticle or main reticle) may be used to create a circuit pattern to be formed on individual layers of 1C to transfer the pattern to a substrate (eg, a germanium wafer) The upper target portion (for example, including a portion of the crystal grains, one crystal grain or several crystal grains). The transfer of the pattern is typically via imaging onto a layer of radiation-sensitive material (resist) provided on the substrate. In general, a single substrate will contain a network of sequentially patterned adjacent target portions. Known lithography apparatus includes a so-called stepper in which each target portion is illuminated by exposing the entire pattern to a target portion at a time; and a so-called scanner that is made in a given direction ("scanning") Each of the target portions is illuminated by scanning the pattern via the radiation beam while scanning the substrate in parallel or anti-parallel in this direction. It is also possible to transfer the pattern from the patterned device to the substrate by imprinting the pattern onto the substrate. In order to monitor the lithography process, it is necessary to measure the misalignment between the parameters of the patterned substrate, e.g., between successive layers formed in or on the substrate. There are various techniques for direct measurement of the 145019.doc 201118366 for the microstructure formed in the lithography process, including the use of scanning electron microscopes and various specialized tools. a special type of detection tool is a scatterometer that directs a beam of radiation onto a target on the surface of the substrate and measures the scattered or reflected beam of light that is reflected by the comparison beam or The lightness of the substrate before and after the scattering can determine the properties of the substrate. This can be done, for example, by comparing the reflected beam to data stored in a library of measurements associated with known substrate properties. Two main types of scatterometers are known. A spectroradiometer directs the broadband radiation beam onto the substrate and measures the spectrum of the radiation (which is a function of the wavelength of the material) that is scattered into a particular narrow range of angles. (d) The scatterometer is used to illuminate the beam of light and measure the intensity of the scattered radiation as a function of angle. In order to measure the spectrum, the reflected radiation beam must be focused on the scatterometer detector. Since it is difficult to use the broadband radiation beam for scatterometry to determine the optimum height of the objective above the target to achieve the best focus, it is known to use a dedicated focus sensor with its own narrowband radiation source. Perform the necessary measurements. The measured values are then used to control the position of the objective lens to maintain the target at the best focus' and to determine the height of the reference in the scatterometer for reference and calibration. However, the inventor of the present invention has recognized that there is a problem in the configuration f that the optimal position of the objective lens as measured by the focus sensor may not be accurately matched to the scatterometer. The best focus position of the detector. SUMMARY OF THE INVENTION It is desirable to provide a detection method using a scatterometer in which at least this problem is alleviated. 145019.doc 201118366 In accordance with a first aspect of the present invention, a scatterometer configured to measure properties of a substrate is provided, comprising: a focus configuration; a focus sensor; a focus controller responsive to the focus sense The detector provides a control signal effective to cause the actuator to be disposed in the adjustment program (4) to adjust the relative position of the focus configuration to the substrate; and a focus offset configuration that is adapted to bias The shift is provided to the focus produced by the focus configuration to compensate for the difference between the focus of the scatterometer during the adjustment procedure and the focus of the scatterometer during use of the scatterometer. According to a second aspect of the present invention, there is provided a scattering measurement method for measuring a property of a substrate using a scatterometer, comprising: an adjustment program comprising: determining the focus configuration required for focusing a light beam and the substrate a relative position; providing a control signal indicating the relative position of the focus configuration and the substrate; and adjusting the relative positions of the focus configuration and the substrate to cause the focus depending on a control signal such as 3; A focus is generated by the focus configuration to compensate for the difference between the focus of the scatterometer during the adjustment procedure and the focus of the scatterometer during use of the scatterometer. According to a third aspect of the present invention, there is provided a device manufacturing method, the package of 145019.doc 201118366 comprising: using a lithography device to form a pattern on a substrate; and using a scatterometer to determine the color printed by the lithography device a parameter-related value of the pattern, comprising: an adjustment procedure comprising: determining a relative position of the focus configuration and the substrate required to focus the radiation beam; providing control indicating the relative position of the focus configuration and the substrate And adjusting the relative position of the focus configuration to the substrate to cause the focus based on the control signals; and providing an offset to a focus generated by the focus configuration to compensate for the adjustment procedure during the adjustment procedure The difference between the focus of the scatterometer and the focus of the scatterometer during use of the scatterometer. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described by way of example only with reference to the accompanying drawings, in which FIG. Figure 1 unintentionally depicts a lithography apparatus. The apparatus comprises: - a lighting system (illuminator) ratio configured to adjust a radiation beam B (eg, UV radiation or radiation); a support structure (eg, a reticle stage) MT constructed in a branch pattern Such as a 'mask' MA, and connected to a first locator PM configured to position the patterned device according to certain parameters; 145019.doc 201118366 - substrate table (eg, wafer table) WT, Constructed to hold the substrate (eg, a second locator PW that is coated against the ribs to accurately position the substrate according to certain parameters; and
-投影系統（例如，折射投影透鏡系統）pL，其經組態以 將藉由圖案化器件MA賦予至輻射光束B w之目標部分c(例如，包含一或多個晶粒)上。和至基板 照明系統可包括用於引導、成形或控制輻射的各種類型 之光學組件，諸如折射、反射、磁性、電磁 '靜電或其他 類型之光學組件，或其任何組合。 支撐結構支揮（亦即，承載）圖案化器件。支樓結構以取 決於圖案化器件之定向、微影裝置之設計及其他條件（諸 如圖案化器件是否固持於真空環境中)的方式來固持圖案 化器件。支撐結構可使用機械、真空、靜電或其他夾持技 術來固持圖案化器件。支I结構可為（例如）框架或台，其 可根據需要而係固线可移動的。支撐結構可確保圖案化 器件(例如)相對於投影系統處於所要位置。可認為本文對 術-主光罩」或「光罩」之任何使用均與更通用之術語 「圖案化器件」同義。 本文所使用之術語「圖案化器件」應被廣泛地解釋為指 代可用以在輻射光束之橫截面中向輻射光束賦予圖案以便 在基板之目標部分中形成圖案的任何器件。應注意，例 如’若被料至輻射光束之圖案包括相移特徵或所謂的輔 助特徵’貝刚可能不會精確地對應於基板之目標部分中 的所要圖案。通常’被賦予至輕射光束之圖案將對應於目 1450l9.doc 201118366 標部分中所形成之器件（諸如積體電路）中的特定功能層。 圖案化器件可係透射或反射的。圖案化器件之實例包括 光罩、可程式化鏡面陣列，及可程式化LCD面板。光罩在 微影中係熟知的，且包括諸如二元、交變相移及衰減相移 之光罩類型，以及各種混合光罩類型。可程式化鏡面陣列 之一實例使科鏡面之料配置，料小鏡面巾之每一者 可個別地傾斜，以便在不同方向上反射入射輕射光束。傾 斜鏡面將圖案賦予於由鏡面矩陣所反射之輻射光束令。 本文所使用之術語「投影系統」應被廣泛地解釋為涵蓋 任何類型之投影系統’包括折射、反射、反射折射、磁 性、電磁及靜電光學系統或其任何組合，其適合於所使用 之曝光輻射’或適合於諸如浸沒液體之使用或真空之使用 的其他因素。可認為本文對術語「投影透鏡」之任何使用 均與更通用之術語「投影系統」同義。 匕處所插繪’ I置為透射類型(例如，使用透射光 罩）°或者’裝置可為反射類型（例如，使用如以上所提及 之:員型的可程式化鏡面陣列，或使用反射光罩)。 微影裝置可為具有兩個（雙平台）或兩個以上基板台（及/ ^兩個或兩個以上光罩台)的類型。在該等「多平台」機 器中’可並行地使用額外台’或可在一或多個台上進行預 備步驟，同時將一或多個其他台用於曝光。 微影裝置亦可為如下類型：其中基板之至少一部分可藉 2有相對較高折射率之液體(例如，水)覆蓋，以便填二 u統與基板之間的空間。亦可將浸沒液體施加至微影 145019.doc 201118366 裝置中之其他空間’例如，光罩與投影系統之間。浸沒技 術在此項技術中被熟知用於增加投影系統之數值孔徑。如 本文所使用之術語「浸沒」+意謂諸如基板之結構:須浸 潰於液體中，而是僅意謂液體在曝光期間位於投影系統與 基板之間。 參看圖1，照明器IL自輻射源S0接收輻射光束。舉例而 言，當輻射源為準分子雷射時，輻射源與微影裝置可為單 獨貫體纟„玄等情况了，不認為輕射源开）&微影裝置之一 部分，且輻射光束係藉助於包含（例如）適當引導鏡面及/或 光束擴展益之光束傳送系統BD而自輻射源s〇傳遞至照明 器IL。在其他情況下，例如，當輻射源為汞燈時，賴射源 可為微影裝置之整體部分。輻射源犯及照明器几連同光束 傳送系統BD(在需要時）可被稱作輻射系統。 。照明器IL可包含用於調整輻射光束之角強度分布的調整 °° 通$，可調整照明器之光曈平面中之強度分布的 ^少外部徑向範圍及/或内部徑向範圍（通常分別被稱作〇外 部及σ内部）。此外，照明器IL可包含各種其他組件，諸如 積光态IN及聚光器c〇。照明器可用以調節輻射光束，以 在其橫截面中具有所要均一性及強度分布。 輻射光束B入射於被固持於支撐結構（例如，光罩台河丁） 上之圖案化器件（例如，光罩MA)上，且係藉由圖案化器件 而圖案化。在橫穿光罩!^八後，輻射光束B傳遞通過投影系 統pL，投影系統PL將光束聚焦至基板w之目標部分匚上。 藉助於第二***PW及位置感測器IF(例如，干涉量測器 1450l9.doc 201118366 件、線性編碼器、2D編碼器或電容性感測器），基板台WT 可準確地移動’例如，以便在輻射光束B之路徑中定位不 同目標部分C。類似地，第—***pM及另一位置感測器 (其未在圖1中被明確地描繪）可用以（例如）在自光罩庫之機 械擷取之後或在掃描期間相對於輻射光束B之路徑來準確 地定位光罩MA。-般而言，可藉助於形成第__***pM 之一部分的長衝程模組（粗略定位）及短衝程模組（精細定 位）來實現光罩台MT之移動。類似地，可使用形成第二定 位器PW之一部分的長衝程模組及短衝程模組來實現基板 台WT之移動。在步進器（與掃描器相反）之情況下，光罩台 MT可僅連接至短衝程致動器，或可係固定的。可使用光 罩對準標記Ml、M2及基板對準標記ρι、以對準光罩心 與基板W。儘管如所說明之基板對準標記佔用專用目標部 分’但其W目標部分之間的空間中（此等被稱為切割 道對準標記）。類似地，在—個以上晶粒提供於光罩MA上 之情形中，光罩對準標記可位於該等晶粒之間。. 所描繪裝置可用於以下模式中之至少一者中： 1.在步進模式中，在將被贼予至輻射光束之整個圖案一 次性投影至目標部分C上時’使光罩台财及基板台WT保a projection system (e.g., a refractive projection lens system) pL configured to be applied to the target portion c (e.g., comprising one or more dies) of the radiation beam Bw by the patterned device MA. And to the substrate illumination system can include various types of optical components for guiding, shaping, or controlling radiation, such as refractive, reflective, magnetic, electromagnetic 'electrostatic or other types of optical components, or any combination thereof. The support structure supports (ie, carries) the patterned device. The fulcrum structure holds the patterned device in a manner that depends on the orientation of the patterned device, the design of the lithography device, and other conditions, such as whether the patterned device is held in a vacuum environment. The support structure can hold the patterned device using mechanical, vacuum, electrostatic or other clamping techniques. The support I structure can be, for example, a frame or table that can be secured by a securing line as desired. The support structure ensures that the patterned device is, for example, in a desired position relative to the projection system. Any use of the "master-mask" or "reticle" herein is considered synonymous with the more general term "patterned device." The term "patterned device" as used herein shall be interpreted broadly to refer to any device that can be used to impart a pattern to a radiation beam in a cross-section of a radiation beam to form a pattern in a target portion of the substrate. It should be noted that, for example, if the pattern of the radiation beam is included to include a phase shifting feature or a so-called auxiliary feature, it may not exactly correspond to the desired pattern in the target portion of the substrate. Typically, the pattern imparted to the light beam will correspond to a particular functional layer in a device (such as an integrated circuit) formed in the section of the reference numeral 1450l.doc 201118366. The patterned device can be transmissive or reflective. Examples of patterned devices include photomasks, programmable mirror arrays, and programmable LCD panels. Photomasks are well known in lithography and include reticle types such as binary, alternating phase shift and attenuated phase shift, as well as various hybrid reticle types. An example of a programmable mirror array allows the mirror surface material to be configured so that each of the small mirror towels can be individually tilted to reflect the incident light beam in different directions. The oblique mirror imparts a pattern to the radiation beam that is reflected by the mirror matrix. The term "projection system" as used herein shall be interpreted broadly to encompass any type of projection system 'including refractive, reflective, catadioptric, magnetic, electromagnetic, and electrostatic optical systems, or any combination thereof, suitable for the exposure radiation used. 'Or suitable for other factors such as the use of immersion liquid or the use of vacuum. Any use of the term "projection lens" herein is considered synonymous with the more general term "projection system."匕 插 ' I I I I I I I I I I I I I I I I I I I I I I I I I I 或者 或者 ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' cover). The lithography device can be of the type having two (dual platforms) or more than two substrate stages (and /^ two or more reticle stages). In such "multi-platform" machines, 'additional stations can be used in parallel' or a preparatory step can be performed on one or more stations while one or more other stations are used for exposure. The lithography apparatus can also be of the type wherein at least a portion of the substrate can be covered by a liquid having a relatively high refractive index (e.g., water) to fill the space between the substrate and the substrate. The immersion liquid can also be applied to the lithography 145019.doc 201118366 Other spaces in the device', for example, between the reticle and the projection system. Immersion techniques are well known in the art for increasing the numerical aperture of a projection system. The term "immersion" as used herein means a structure such as a substrate that must be impregnated into a liquid, but rather only means that the liquid is located between the projection system and the substrate during exposure. Referring to Figure 1, illuminator IL receives a radiation beam from radiation source S0. For example, when the radiation source is a quasi-molecular laser, the radiation source and the lithography device may be a single body, and the light source is not considered to be a part of the lithography device, and the radiation beam is It is transmitted from the radiation source s to the illuminator IL by means of a beam delivery system BD comprising, for example, a suitable guiding mirror and/or beam extending benefit. In other cases, for example, when the radiation source is a mercury lamp, The source may be an integral part of the lithography apparatus. The radiation source illuminator and the illuminator together with the beam delivery system BD (when needed) may be referred to as a radiation system. The illuminator IL may comprise an angular intensity distribution for adjusting the radiation beam. Adjust ° ° to $, to adjust the intensity distribution of the illuminator in the pupil plane, the outer radial range and / or the inner radial range (usually referred to as the outer and inner σ, respectively). In addition, the illuminator IL Various other components may be included, such as a built-in state IN and a concentrator c. The illuminator may be used to adjust the radiation beam to have a desired uniformity and intensity distribution in its cross section. The radiation beam B is incident on the support junction. On a patterned device (eg, reticle MA) on a structure (eg, reticle), patterned by a patterned device. After traversing the reticle, the radiation beam B passes through Projection system pL, the projection system PL focuses the beam onto the target portion of the substrate w. By means of the second positioner PW and the position sensor IF (for example, interference measure 1450l9.doc 201118366 pieces, linear encoder, 2D Encoder or capacitive sensor), the substrate table WT can be accurately moved 'for example, to locate different target portions C in the path of the radiation beam B. Similarly, the first positioner pM and another position sensor (which Not explicitly depicted in Figure 1) can be used to accurately position the reticle MA, for example, after a mechanical extraction from a reticle library or during a scan relative to the path of the radiation beam B. The movement of the reticle stage MT is achieved by means of a long stroke module (rough positioning) and a short stroke module (fine positioning) forming part of the __ locator pM. Similarly, the formation of the second locator PW can be used. Part of the long stroke module and short stroke The group is used to effect the movement of the substrate table WT. In the case of a stepper (as opposed to a scanner), the reticle stage MT can be connected only to a short-stroke actuator, or can be fixed. A reticle alignment mark can be used. Ml, M2 and substrate alignment marks ρι to align the reticle with the substrate W. Although the substrate alignment marks occupy a dedicated target portion as illustrated, but in the space between their target portions (this is referred to as The scribe line alignment mark). Similarly, in the case where more than one die is provided on the reticle MA, the reticle alignment mark may be located between the dies. The device depicted may be used in the following modes In at least one of the following: 1. In the step mode, when the entire pattern of the thief to the radiation beam is projected onto the target portion C at a time, the reticle and the substrate WT are protected.
持基本上靜止（亦即，單次靜態曝光）。接著，使基板台WT 在X及/或γ方向上移位’使得可曝光不同目標部分C。在 :進模式中，曝光場之最大尺寸限制單次靜態曝 像之目標部分C的尺寸。 取 2.在掃描模式中，在將被賦Μ㈣光束之圖案投影至 145019.doc 201118366 目標部分c上時，同步地掃描光罩台Μτ與基板台WT(亦 即，單次動態曝光）。可藉由投影系統PL之放大率（縮小率） 及影像反轉特性來判定基板台WT相對於光罩台Μτ之速度 及方向。在掃描模式中，曝光場之最大尺寸限制單次動態 曝光中之目標部分的寬度（在非掃描方向上），而掃描運動 之長度判定目標部分之高度（在掃描方向上）。 3.在另一模式中，在將被賦予至輻射光束之圖案投影至 目標部分C上時，使光罩台肘丁保持基本上靜止，從而固持 可程式化圖案化器且移動或掃描基板台WT。在此模 式中，通常使用脈衝式輻射源，且在基板台WT2每一移 動之後或在掃描期間的順次輻射脈衝之間根據需要而更新 可程式化圖案化器件。此操作模式可易於應用於利用可程 式化圖案化器件（諸如以上所提及之類型的可程式化鏡面 陣列）之無光罩微影。 亦可使用對以上所描述之使用模式之組合及/或變化或 完全不同的使用模式。 如圖2所不，微影裝置LA形成微影單元lc(有時亦被賴 作微影單元或叢集）之料，其亦包括心對基板執行畴 光前及曝光後處理程序之|置。通常，此等裝置包括用〇 沈積抗㈣層之旋塗說、用以顯影經曝光抗㈣之顯最 器DE、冷卻板CH’及烘烤㈣艮。基板處置器或機器人以 自輸入/輸出槔職、1/02拾取基板、在不同處理程序裝f 之間移動基板，且接菩將其此# 者將基板傳送至微影裝置之裝載盘 LB。通常被集體地稱作塗布顯影系統(track)之此等器件^ 145019.doc 12 201118366 在=布顯影系、统控制單元Tcu之控制下，、塗布顯影系統控 制單元TCU自身係藉由監督控制系統scs控制，監督控制 系統SCS亦經由微影控制單元LACU而控制微影裝置。因 此，不同裝置可經操作以最大化產出率及處理效率。 為了使由微影裝置所曝光之基板正確地且—致地曝光， 需要檢測經曝光基板以量測諸如後續層之間的疊對誤差、 線厚度、臨界尺寸（CD)等等之屬m貞測到誤差，則可 對後續基板之曝光進行調整，尤其係在檢測可被^夠迅速 且快速地進行以使得同-批之其他基板仍待曝光的情況 下。又，已經曝光之基板可經剝離及重做（以改良良率或 廢除）藉此避免對已知為有缺陷之基板執行曝光。在基板 之僅-些目標部分有缺陷的情況下，可僅對良好之彼等目 標部分執行另外曝光。 使用檢測裝置以判定基板之屬性，且特別係判定不同基 板或同-基板之不同層的屬性如何在層與層之間變化。檢 測裝置可經整合至微影裝置LA或微影單元LC中或可為獨 立為了實現最快量測，需要使檢測裝置在曝光之後 立即量測經曝光抗蝕劑層中之屬纟。然而，抗蝕劑中之潛 影具有極低對比度（在已曝光至輻射的抗㈣彳之部分與尚 未曝先至輻射的抗#劑之部分之間僅存在極小的折射率 所有檢測裝置均具有對進行潛影之有用量測的 θ f±因此，可在曝光後烘烤步驟（PEB)之後採取 u:後供烤步驟_)通常為對經曝光基板所進行 之V驟且其增加抗鞋劑之經曝光部分與未經曝光部分 145019.doc 201118366 之間的對比度。在此階段’抗钮劑中之影像可被稱作半潛 伏的。亦有可能進行經顯影抗#劑影像之量測（此時，抗 钱劑之經曝光部分或未經曝光部分已被移除），或在諸如 ㈣之圖案轉印步驟之後進行經顯影抗㈣影像之量測。 後者可能性限制重做有缺陷基板之可能性，但仍可提供有 用資訊。 圖3U用於本發明中之散射計。散射計可包括寬頻 帶（白光）輕射投影儀2,其將輻射投影至基板W。經反射 輻射傳遞至分光計偵測器4，其量測鏡面經反射輻射之光 譜10(作為波長之函數的強度）。自此資料，可藉由處理單 元PU來重新建構引起經偵測光譜之結構或資料檔 (P “e)例如’藉由嚴密耦合波分析及非線性回歸或藉 由與如圓3之底部處所示之模擬光譜庫相比較。一般而 言’為了重新建構，吾人已知結構之通用形式，且根據對 製造結構所採用之處理程序的認識來假卜些參數，從而 僅留下結構之少許參數以自散射量測資料加以判定。該散 射計可經組態為正入射散射計或斜入射散射計。 圖4中展示可用於本發明之另一散射計。在此器件中， 由輻射源2所發射之輻射係使用透鏡系統12而聚焦通過干 涉遽光器13及偏振器17、藉由部分反射表面16反射且經由 顯微鏡接物鏡15而聚焦至基板W上，顯微鏡接物鏡15具有 高數值孔徑（NA)，較佳地為至少0.9且更佳地為至少〇.95。 浸沒散射計可甚至具有數值孔徑超過丨之透鏡。經反射輻 射接著通過部分反射表面16而透射至彳貞測H 18中，以便偵 145019.doc 201118366 測散射光譜。偵測器可位於處於透鏡系統15之焦距的背部 投影式光瞳平面11中，然而，光曈平面可代替地藉由輔助 光學儀器（未圖示）而再成像至偵測器上。光瞳平面為輻射 之徑向位置界定入射角且角位界定輻射之方位角的平面。 偵測器較佳地為二維偵測器，使得可量測基板目標30之二 維角散射光譜。偵測器18可為（例如）CCD或CM〇s感測器 陣列，且可使用為（例如）每圖框40毫秒之積分時間。 舉例而言，通常使用參考光束以量測入射輻射之強度。 為了進行此過程，當輻射光束入射於光束***器16上時， 使輻射光束之一部分透射通過光束***器以作為朝向參考 鏡面14之參考光束。接著將參考光束投影至同一偵測器18 之不同部分上。 干涉濾光器13之集合可用以選擇在（比如）4〇5奈米至79〇 奈米或甚至更低（諸如200奈米至300奈米）之範圍内的所關 注波長。干涉濾光器可係可調諧的，而非包含不同滤光器 之集合。可使用光柵以代替干涉濾光器。 偵測器18可量測經散射光在單一波長（或窄波長範圍）下 之強度、單獨地在多個波長下之強度’或在—波長範圍内 所積分之強度。此外’ m可單獨地量測橫向磁偏振光 及橫向電偏振光之強度’及/或橫向磁偏振光與橫向電偏 振光之間的相位差。 使用寬頻帶光源(亦即’具有寬光頻率或波長範圍且因 此具有寬顏色範圍之光源）係可能的，其給出較大光展量 (etendue)，從而允許多個波長之混合。在寬頻帶中之複數 145019.doc 201118366 個波長較佳地各自具有為*8之頻寬及為至少2*8(亦即，為 頻寬之兩倍）之間隔。若干輻射「源」可為已使用光纖束 而***的延伸式輻射源之不同部分。以此方式，可在多個 波長下並行地量測角度解析散射光譜。可量測3D光譜（波 長及兩個不同角度），其與2D光譜相比較含有更多資訊。 此允s午量測更多資訊，其增加度量衡處理程序穩固性。此 在£卩1，628，164八中得以更詳細地描述。 基板W上之目標30可為光柵，其經印刷，使得在顯影之 後，條狀物（bar)係由固體抗蝕劑線形成。條狀物可或者經 蝕刻至基板中。此圖案對微影投影裝置（特別係投影系統 PL)中之色像差敏感，且照明對稱性及該等像差之存在將 使其自身表現為經印刷光柵之變化。因此，使用經印刷光 柵之散射量測資料來重新建構光柵。根據對印刷步驟及/ 或其他散射量測處理程序之認識，可將光柵之參數（諸如 線寬及形狀）輸入至由處理單元pu所執行之重新建構處理 程序。 現亦參看圖5，此圖展示圖4所說明之散射計之結構。散 射计係藉由基底框架5 1支撐，基底框架5丨支撐經支撐以用 於在由箭頭所展示之方向上移動的線性γ平台53及經支撐 以用於在圖式之平面中移動的線性χ平台55。線性γ平台 53載運旋轉平台57,旋轉平台57又載運將在使用裝置時載 運晶圓W之晶圓台59。提供圖4所指示之散射計感測器 18，其係藉由線性χ平台55支撐，以便可沿著χ方向移 動。 145019.doc -16- 201118366 為了藉由接物鏡系統15而在基板上提供輻射光束之線上 聚’、、:散射a十包括焦點感測配置。詳言之，提供藉由散射 。十感測器18所載運且可隨著散射計感測器丨8而移動之焦點 感測器61，焦點感測器61又載運控制圖4所指示之接物鏡 系統15之位置的接物鏡平台63。焦點照明系統&經配置以 將在该圖中指示為箭頭之輻射光束引導至焦點感測器幻 上:此光束將通過接物鏡系統15而傳遞至晶圓〜上。在處 單元PU之控制下，焦點控制器67有效於將控制信號提供 物鏡平口 63中之致動器(未圖示），以便控制在z方向 上接物鏡配置之移動（如由該圖中之箭頭所指示），以便將 由焦點照明线所提供之輻射聚焦至晶Hi，且將由晶圓 台59上之晶gjw所反射之輻射聚焦回至焦點感測㈣上。 然而’如由發明人所瞭解，以上所描述之配置仍然存在 以下問題：在量測自晶圓所反射之輕射光譜以便監視(例 如)田臨界尺寸（CD)或疊對（〇v)時，由焦點感測器Η所量測 之最佳焦點量測未必匹配於為ώ 於马由政射叶感測器18所進行之 量測所需要的最佳焦點。此可歸 孓以下各項：歸因於輻 射中之不同波長的或歸因 、个丨j屌理（诸如電容性相 光學對比度）之不同光擧却_呌沾a 、 子°又6十的由散射計感測器18及焦點 感測器61所使用之不同量測技 议1丨了，日日111台59上之晶圓之不 同日日圓相互作用；或用於不同岸 曰、， 个U應用（例如，在CD量測與〇v ϊ測之間）之最佳焦點之不同定義。 疋我知因於時間限制，不 可能在藉由裝置之散射計量彳 一 £认旦^ T里劂期間藉由焦點感測器6!來進 仃另卜里測。詳言之，由焦點控制 J系統所使用之取樣將通 I450l9.doc • 17· 201118366 常具有通常為2 KHz之頻寬， 頻寬小得多》 其比用於散射量測之輻射之 根據本發明之一實施例，在散射計量測期間調整在Z方 向上焦點感測器之位置’以補償焦點感測器與散射量測感 測益1 8之焦點之間的偏移’而無需線性化焦點感測器。 現參看目6，此說明用於以上大體上所描述之焦點感 測配置之光學配置中-些光學組件之位置，其可用於根據 本發明之一貫施例之散射計中。應瞭解，在圖6中，晶圓 W為圖5所描繪之散射計中所展示之晶圓w，而透鏡的構成 圖5所描繪之接物鏡配置15，透鏡71為用於焦點感測配置 之聚焦透鏡。亦應瞭解一些光學組件（尤其係光束***配 置）係用於***由晶圓所反射之輻射，使得僅來自焦點照 明系統65之輻射傳遞通過聚焦透鏡71。 自晶圓W所反射的傳遞通過透鏡69、7丨之輻射係藉由鏡 面73***以產生兩個光束（光束1及光束2)。提供各別偵測 器75及77以偵測光束1及光束2 ^光束1通過孔徑79而傳遞 至偵測器75上，而光束2在自鏡面83反射之後通過孔徑8 j 而傳遞至偵測器77上，偵測器75、77、孔徑79、8 1及鏡面 73、83均形成圖5之焦點感測器6 1之一部分。圖6亦說明用 於每一光束（光束1及光束2)之各別焦平面85、87之位置。 晶圓W與用於光束1之焦平面85之間的光徑長度將等於晶 圓W與光束2之焦平面87之間的光徑長度。孔徑79、81與 各別焦平面85、87之間的距離針對光束1及光束2將相同。 兩個光束（光束1及光束2)之使用實現光束與晶圓W上之 145019.doc -18 · 201118366 實'點：：之任何偏差的感測’以及待偵測之任何散焦的事 曰j 5之，在最佳焦點處，傳遞通過孔徑79、S1之光的 :相$等1 ’因此’偵測器75、77之輸出S1、以亦相等。換言 S2/ 且Sl-S2=〇。若晶圓W不處於最佳焦‘點，則“與 得不同且此可被偵測到。接著使用圖5所示之接物鏡 平口 63來移動接物鏡配置15中接物鏡69之位置，直至^與 S2再次變得相等為止’晶圓W接著處於最佳焦點，其中接 物鏡69針對散射量測及對準量測兩者均處於晶DW上方之 最佳高度。如以上所解釋，關於先前技術，先前技術配置 :在以下問題：在散射量測感測器之焦點與焦點感測器之 “、、之間可存在差，其可係基於機器、產品及/或處理程 序。 =亦參看圖7’根據本發明之第一實施例，線外執行參 考1測，以判定如藉由焦點感測配置所判定之焦點與為特 定散射量測㈣中所使用之特定輕射光束所需要之焦點之 間的偏移。此指示為圖7中之步驟S7丨。在步驟奶中，可 在政射计之線上操作期間在進行中之基礎上校正如藉由焦 點感測器61及散射計感測器18所量測的入射於晶圓w上之 光束之焦點量測之間的偏移，而無需以其他方式再調整 統。 ’、 針對偏移之校正可在焦點感測配置中或在散射計感測器 18中進行。在此特定實施例中，在圖6所說明之光學配置 中，可調整聚焦透鏡71之位置（其在先前技術配置中通常 保持靜態）以改變焦平面85、87相對於各別孔徑79、“之 U5019.doc • 19- 201118366 位置。此位置調整可藉由調整接物鏡69之位置的同一致動 器執行或藉由單獨致動器執行。在使焦平面85移位成更接 近光束1中之針孔79的情況下’相對於由偵測器77所產生 之k號，偵測器75將產生更大信號。因此，S1將大於S2。 信號之差S1-S2可藉由控制器67用於焦點控制迴路中，以 調整接物鏡69之位置，其將又影響焦平面85之位置。控制 迴路將再次移動接物鏡69直至S1與S2相等為止，且焦平面 85返回至其原始位置。將看出，#由此程序，與不存在偏 移之施加相比較，相對於晶圓w不同地定位接物鏡69。此 將影響散射計感測器18及藉由焦點感測器61所進行之量測 所實現之對準功能兩者的焦點。 或者，可調整孔徑79、81之位置。—旦已校正偏移，焦 點控制器67便藉由移動接物鏡平台63而確保使用經校正焦 點位置來採取藉由散射計感測器系統18中之偵測器75、77 所進行之量測。雖然聚焦系統摘測最佳焦點位置（亦即， ㈣)，但在焦點感測器外部針對量測系統而引入偏移。 現參看圖8,在根據本發明之_#代實施射，代替如 在第-實施例中調整光學組件，可對藉由焦點控制器⑺施 加至接物鏡平台63中之致動器之信號進行軟體校正。如在 第-實施例I在步驟S81中’料執行參考量測，以判 定如藉由焦點感測配置所判;^之焦點與為特^散射量測操 作中所使用之特定輕射光束所需要㈣移。在 後續線上散射量測操作中’如步驟如中所指#，在處理 器PU之控制下 焦點控制 器67接著經配置以提供經修改控 145019.doc -20- 201118366 制信號，亦即，代替使，使sms2且有等於一 偏移值之差。此接著係用以在考慮到偏移之情況下控制接 物鏡平台63中之致動器以將接物鏡系統之位置調整至㈣ 由焦點控制器所判定之最佳焦點位置。然而，應瞭解，此 實施例之實施要求在焦點感測器61之輸出與接物鏡系統之 實際線性位移之間存在已知關係，理想地為線性關係、。此 將取決於許多因素，包括經量測之晶圓w之結構。 。應瞭解，與特定應用或聚焦系統無關，對於散射計感測 器18或焦點感測器61 ’針對焦點感測器與散射量測感測器 之，、、、點^間的偏移的校正將允許獲得㈣於最佳焦點之更 小焦點^差。此將弓丨扭益山 子5丨起糟由以上所描述之晶圓定位系統的 散射計之組件之更佳對準，其將引起更準確的CD及/戍0V 量測。此外’用於量測經散射輻射之更佳焦點亦將引起更 準確的CD及/或OV量測。更佳焦點將引起用於藉由以上所 描述之晶圓定位系統的晶圓之對準的更清晰影像，從而引 起更J對準決差。在0V量測之情況下，將有可能遍及晶 圓而選擇在何處進行量測，因為最佳焦點將不取決於晶 圓。 外亦應瞭解’針對偏移之調整的可能性允許焦點感測器之 十中之更夕靈居性。同樣地，不要求感測器提供最佳可 能焦點，因為其可陆你丄 、 、^後加以校正。此外，可改良散射量測 & t t H從而藉由使有可能變化入射輪射之強 度而使有可能(例如)量測自不良反射表面所產生之光譜。 偏移校正亦將使县μ杳 ;貫施以上所描述之光學感測器的替代 145019.doc -21 · 201118366 焦點感測ϋ(例如，電容性感測器），但其接著將有必要提 供不同控制系統。在使用該電容性感測器時，在調整程序 中判定接物鏡之最佳焦點位置，電容性感測器係用以判定 晶圓w與接物鏡69之相對位置。將偏移施加至由電容性感 測器所產生之信號，以補償調整程序與散射計之操作之間 的量測特性之改變。 儘管在本文中可特定地參考微影裝置在1C製造中之使 用，但應理解，本文所描述之微影裝置可具有其他應用， 諸如製造整合光學系統、用於磁疇記憶體之導引及偵測圖 案、平板顯示器、液晶顯示器(LCD)、薄膜磁頭等等。 熟習此項技術者應瞭解，在該等替代應用之情境中，可認 為本文對術浯「晶圓」#「晶粒」之任何使用分別與更通 用之術語「基板」《「目標部分」同義。可在曝光之前或 之後在（例如）塗布顯影系統（通常將抗蝕劑層施加至基板且 顯影經曝光抗蝕劑之工具）、度量衡工具及/或檢測工具中 處理本文所提及之基板。適用時，可將本文之揭示内容應 用於6亥等及其他基板處理工纟。另夕卜，可將基板處理一次 以上（例如）以便形成多層1C，使得本文所使用之術語基 板亦可指代已經含有多個經處理層之基板。 儘官以上可特定地參考在光學微影之情境中對本發明之 實施例的使用，但應瞭解，本發明可用於其他應用（例 如，壓印微影）中，且在情境允許時 不限於光學微影。在 壓印微影中，圖案化器件中之構形界定形成於基板上之圖 案可將圖案化器件之構形壓人被供應至基板之抗g劑層 145019.doc -22· 201118366 中，在基板上，抗蝕劑係藉由施加電磁輻射、熱、壓力或 其組合而固化。在抗蝕劑固化之後，將圖案化器件移出抗 钮劑’從而在其中留下圖案。 本文所使用之術語「輕射」及「光束」；函蓋所有類型之 電磁輕射’包括紫外線（uv)輻射（例如，具有為或為約祕 奈米、355奈米、248奈米、193奈米、157奈米或I%奈米 之波長）及極紫外線（贿)輻射（例如，具有在為5奈米至2〇 奈米之範圍内的波長）；以及粒子束（諸如離子束或 束）。 術語「透鏡」在情境允許時可指代各種類型之光學組件 中之任一者或其組合，包括折射、反射、磁性、電磁及靜It is essentially stationary (ie, a single static exposure). Next, the substrate stage WT is displaced in the X and/or γ directions so that different target portions C can be exposed. In the advance mode, the maximum size of the exposure field limits the size of the target portion C of a single static exposure. 2. In the scan mode, when the pattern of the assigned (four) beam is projected onto the target portion c of 145019.doc 201118366, the mask stage τ and the substrate stage WT (i.e., single dynamic exposure) are synchronously scanned. The speed and direction of the substrate stage WT with respect to the mask stage τ can be determined by the magnification (reduction ratio) and the image inversion characteristic of the projection system PL. In the scan mode, the maximum size of the exposure field limits the width of the target portion in a single dynamic exposure (in the non-scanning direction), and the length of the scanning motion determines the height of the target portion (in the scanning direction). 3. In another mode, when the pattern to be imparted to the radiation beam is projected onto the target portion C, the reticle elbow is kept substantially stationary, thereby holding the programmable patterner and moving or scanning the substrate table WT. In this mode, a pulsed source of radiation is typically used, and the programmable patterning device is updated as needed between each movement of substrate table WT2 or between successive pulses of radiation during the scan. This mode of operation can be readily applied to reticle lithography utilizing a programmable patterning device, such as a programmable mirror array of the type mentioned above. Combinations of the modes of use described above and/or variations or completely different modes of use may also be used. As shown in Fig. 2, the lithography apparatus LA forms a material of the lithography unit lc (sometimes also referred to as a lithography unit or cluster), which also includes the center-to-substrate execution of the pre-domain and post-exposure processing. Typically, such devices include a spin coating for depositing an anti-(four) layer, a developing device DE for developing an exposure (4), a cooling plate CH', and a baking (four) crucible. The substrate handler or the robot picks up the substrate from the input/output, picks up the substrate in 1/02, moves the substrate between different processing programs, and transmits the substrate to the loading tray LB of the lithography apparatus. These devices, which are collectively referred to collectively as coating development systems, 145019.doc 12 201118366 Under the control of the control system, the control unit TCU, the coating development system control unit TCU itself is controlled by the supervisory control system. The scs control, supervisory control system SCS also controls the lithography device via the lithography control unit LACU. Therefore, different devices can be operated to maximize yield and processing efficiency. In order to properly and uniformly expose the substrate exposed by the lithography apparatus, it is necessary to detect the exposed substrate to measure the misalignment error such as the subsequent layer, the line thickness, the critical dimension (CD), and the like. When an error is detected, the exposure of the subsequent substrate can be adjusted, especially if the detection can be performed quickly and quickly so that the other substrates of the same batch are still to be exposed. Also, the exposed substrate can be peeled and reworked (to improve yield or abolish) thereby avoiding exposure to a substrate that is known to be defective. In the case where only some of the target portions of the substrate are defective, additional exposure may be performed only for the good target portions. A detection device is used to determine the properties of the substrate, and in particular to determine how the properties of different substrates or different layers of the same substrate vary between layers. The detection device can be integrated into the lithography device LA or the lithography unit LC or can be independent for the fastest measurement, and the detection device needs to measure the defects in the exposed resist layer immediately after exposure. However, the latent image in the resist has a very low contrast ratio (there is only a very small refractive index between the portion of the anti-radiation (four) 已 that has been exposed to radiation and the portion of the anti-reagent that has not been exposed to the radiation. θ f± for the measured amount of the latent image, therefore, after the post-exposure bake step (PEB), the u: post-bake step _) is usually performed on the exposed substrate and the anti-shoe is added The contrast between the exposed portion of the agent and the unexposed portion 145019.doc 201118366. The image in the anti-button agent at this stage can be referred to as semi-latent. It is also possible to perform a measurement of the developed anti-drug image (at this time, the exposed portion or the unexposed portion of the anti-money agent has been removed), or after the pattern transfer step such as (4), the development is resistant (4) Measurement of images. The latter possibility limits the possibility of redoing defective substrates, but still provides useful information. Figure 3U is used in the scatterometer of the present invention. The scatterometer can include a wide band (white light) light projector 2 that projects radiation onto the substrate W. The reflected radiation is transmitted to a spectrometer detector 4 which measures the spectrum 10 of the specularly reflected radiation (intensity as a function of wavelength). From this data, the processing unit PU can be used to reconstruct the structure or data file causing the detected spectrum (P “e) such as 'by tightly coupled wave analysis and nonlinear regression or by the bottom of the circle 3 Comparison of the simulated spectral libraries shown. In general, 'for re-construction, we know the general form of the structure, and based on the knowledge of the processing procedures used to fabricate the structure, to abandon some parameters, leaving only a little structure The parameters are determined from self-scattering measurements. The scatterometer can be configured as a normal incidence scatterometer or an oblique incidence scatterometer. Another scatterometer useful in the present invention is shown in Figure 4. In this device, by the radiation source The emitted radiation is focused by the lens system 12 through the interfering chopper 13 and the polarizer 17, reflected by the partially reflective surface 16 and focused onto the substrate W via the microscope objective lens 15, the microscope objective 15 having a high value The aperture (NA), preferably at least 0.9 and more preferably at least 〇.95. The immersion scatterometer may even have a lens with a numerical aperture exceeding 丨. The reflected radiation then passes through the partially reflective surface. 16 is transmitted to the measured H 18 to detect the scatter spectrum of 145019.doc 201118366. The detector may be located in the back projection pupil plane 11 at the focal length of the lens system 15, however, the pupil plane may instead Re-imaging onto the detector by an auxiliary optical instrument (not shown). The pupil plane defines the angle of incidence for the radial position of the radiation and the angular position defines the plane of the azimuth of the radiation. The detector is preferably two The dimension detector enables measurement of the two-dimensional angular scatter spectrum of the substrate target 30. The detector 18 can be, for example, a CCD or CM 〇 sensor array and can be used, for example, for 40 milliseconds per frame. Integral time. For example, a reference beam is typically used to measure the intensity of the incident radiation. To perform this process, when the radiation beam is incident on the beam splitter 16, one of the radiation beams is partially transmitted through the beam splitter as an orientation. Reference beam of reference mirror 14. The reference beam is then projected onto different portions of the same detector 18. The set of interference filters 13 can be selected to be, for example, 4 to 5 nm to 79 nm or even The wavelength of interest in the range of low (such as 200 nm to 300 nm). The interference filter can be tunable rather than containing a collection of different filters. A grating can be used instead of the interference filter. The detector 18 can measure the intensity of the scattered light at a single wavelength (or a narrow wavelength range), the intensity at a plurality of wavelengths alone or the intensity integrated over the wavelength range. Measuring the intensity of the transverse magnetically polarized light and the transversely polarized light and/or the phase difference between the transversely polarized light and the transversely polarized light. Using a broadband light source (ie, 'having a wide optical frequency or wavelength range and therefore having a width A source of color range is possible, which gives a large etendue, allowing mixing of multiple wavelengths. The complex number 145019.doc 201118366 wavelengths in the wide frequency band preferably each have a bandwidth of *8 and an interval of at least 2*8 (i.e., twice the bandwidth). A number of "sources" of radiation may be different portions of an extended source of radiation that has been split using a bundle of fibers. In this way, the angular resolution scattering spectra can be measured in parallel at multiple wavelengths. The 3D spectrum (wavelength and two different angles) can be measured, which contains more information than the 2D spectrum. This allows for more information to be measured in the afternoon, which increases the robustness of the weights and measures handler. This is described in more detail in pp. 1,628,164. The target 30 on the substrate W may be a grating that is printed such that after development, the bars are formed from solid resist lines. The strips can either be etched into the substrate. This pattern is sensitive to chromatic aberrations in lithographic projection devices, particularly projection system PL, and the illumination symmetry and the presence of such aberrations will manifest themselves as changes in the printed raster. Therefore, the grating is reconstructed using the scattering measurement data of the printed grating. Depending on the printing steps and/or other scatterometry processing procedures, the parameters of the raster, such as line width and shape, can be input to the reconstructed processing program executed by processing unit pu. Referring now also to Figure 5, this figure shows the construction of the scatterometer illustrated in Figure 4. The scatterometer is supported by a base frame 5 1 that supports a linear gamma platform 53 that is supported for movement in the direction shown by the arrow and a linear support that is supported for movement in the plane of the drawing χ Platform 55. The linear gamma platform 53 carries a rotating platform 57 which in turn carries a wafer table 59 that will carry the wafer W while the device is in use. A scatterometer sensor 18, as indicated in Figure 4, is provided which is supported by a linear helium platform 55 so as to be movable in the x-direction. 145019.doc -16- 201118366 In order to provide a beam of radiation beam on the substrate by the objective lens system 15, the convergence, a: includes a focus sensing configuration. In detail, it is provided by scattering. The focus sensor 61 carried by the ten sensor 18 and movable along with the scatterometer sensor 丨8, the focus sensor 61 in turn carries the objective mirror platform controlling the position of the objective lens system 15 indicated in FIG. 63. The focus illumination system & is configured to direct the radiation beam indicated as an arrow in the figure to the focus sensor illusion: this beam will be transmitted to the wafer through the objective system 15. Under the control of the unit PU, the focus controller 67 is effective to provide a control signal to an actuator (not shown) in the objective aperture 63 to control the movement of the objective lens configuration in the z-direction (as illustrated by the figure) The arrow is directed to focus the radiation provided by the focus illumination line to the crystal Hi and to focus the radiation reflected by the crystal gjw on the wafer table 59 back onto the focus sensing (4). However, as understood by the inventors, the configuration described above still has the problem of measuring the light-emitting spectrum reflected from the wafer in order to monitor, for example, a critical dimension (CD) or a stack (〇v). The best focus measurement measured by the focus sensor 未 does not necessarily match the best focus required for the measurement by the Ma Yizheng leaf sensor 18. This can be attributed to the following: different light effects due to different wavelengths or attributions in the radiation, such as capacitive phase optical contrast, _ 呌 a, ° ° and 60 The different measurement techniques used by the scatterometer sensor 18 and the focus sensor 61 are different, and the different day yen interactions of the 111 wafers on the 59th day; or for different shores, Different definitions of the best focus of U applications (for example, between CD measurements and 〇v guesses).疋 I know that due to time constraints, it is not possible to use the focus sensor 6! during the measurement of the scattering by the device. In particular, the sampling used by the focus control J system will pass I450l9.doc • 17· 201118366 often has a bandwidth of usually 2 KHz, and the bandwidth is much smaller than the radiation used for the scattering measurement. In one embodiment of the invention, the position of the focus sensor in the Z direction is adjusted during the scatterometry to compensate for the offset between the focus sensor and the focus of the scatter sensory measure 1 8 without linearity Focus sensor. Referring now to Figure 6, this description illustrates the position of some of the optical components used in the optical configuration of the focus sensing configuration described generally above, which can be used in a scatterometer in accordance with a consistent embodiment of the present invention. It should be understood that in FIG. 6, the wafer W is the wafer w shown in the scatterometer depicted in FIG. 5, and the lens constitutes the objective lens configuration 15 depicted in FIG. 5, and the lens 71 is used for the focus sensing configuration. Focusing lens. It will also be appreciated that some optical components, particularly beam splitting configurations, are used to split the radiation reflected by the wafer such that only radiation from the focus illumination system 65 passes through the focusing lens 71. The radiation transmitted from the wafer W through the lenses 69, 7 is split by the mirror 73 to produce two beams (beam 1 and beam 2). The respective detectors 75 and 77 are provided to detect the beam 1 and the beam 2. The beam 1 is transmitted to the detector 75 through the aperture 79, and the beam 2 is transmitted to the detection through the aperture 8j after being reflected from the mirror 83. On the detector 77, the detectors 75, 77, the apertures 79, 81 and the mirrors 73, 83 each form part of the focus sensor 61 of FIG. Figure 6 also illustrates the locations of the respective focal planes 85, 87 for each beam (beam 1 and beam 2). The length of the optical path between the wafer W and the focal plane 85 for the beam 1 will be equal to the length of the optical path between the wafer W and the focal plane 87 of the beam 2. The distance between the apertures 79, 81 and the respective focal planes 85, 87 will be the same for beam 1 and beam 2. The use of two beams (beam 1 and beam 2) achieves the sensing of the beam and the wafer W on the 145019.doc -18 · 201118366 real 'point:: any deviation from the deviation' and any defocusing to be detected j 5, at the best focus, the light passing through the apertures 79, S1: phase $1, etc. 'Therefore the outputs S1 of the detectors 75, 77 are also equal. In other words S2/ and Sl-S2=〇. If the wafer W is not at the optimum focus point, then "the difference is different and this can be detected. Then use the objective lens flat 63 shown in FIG. 5 to move the position of the objective lens 69 in the objective lens configuration 15 until ^ and S2 become equal again until the wafer W is then in the best focus, wherein the objective lens 69 is at the optimum height above the crystal DW for both the scattering measurement and the alignment measurement. As explained above, regarding the previous Technique, prior art configuration: In the following problem: there may be a difference between the focus of the scatterometry sensor and the focus sensor, which may be based on machine, product, and/or processing. Referring also to Figure 7', in accordance with a first embodiment of the present invention, the reference 1 measurement is performed off-line to determine the focus as determined by the focus sensing configuration and the particular light beam used in the particular scattering measurement (4). The offset between the required focus. This indication is step S7 in FIG. In the step milk, the amount of focus of the light beam incident on the wafer w as measured by the focus sensor 61 and the scatterometer sensor 18 can be corrected on an ongoing basis during the line operation of the cyberometer. Measure the offset between them without having to adjust the system in other ways. Correction for offset can be performed in a focus sensing configuration or in scatterometer sensor 18. In this particular embodiment, in the optical configuration illustrated in FIG. 6, the position of the focus lens 71 (which typically remains static in prior art configurations) can be adjusted to change the focal planes 85, 87 relative to the respective apertures 79, " U5019.doc • 19- 201118366 Position. This position adjustment can be performed by the same actuator that adjusts the position of the objective lens 69 or by a separate actuator. The focal plane 85 is displaced closer to the beam 1 In the case of the pinhole 79, the detector 75 will generate a larger signal with respect to the k number generated by the detector 77. Therefore, S1 will be greater than S2. The signal difference S1-S2 can be controlled by the controller 67. It is used in the focus control loop to adjust the position of the objective lens 69, which in turn affects the position of the focal plane 85. The control loop will again move the objective mirror 69 until S1 and S2 are equal, and the focal plane 85 returns to its original position. It will be seen that # this procedure, in contrast to the application of the offset, the objective lens 69 is positioned differently relative to the wafer w. This will affect the scatterometer sensor 18 and by the focus sensor 61. Measure the achieved alignment function Alternatively, the position of the apertures 79, 81 can be adjusted. Once the offset has been corrected, the focus controller 67 ensures that the corrected focus position is used to take the scatterometer sensor system 18 by moving the objective platform 63. The measurement is performed by the detectors 75, 77. Although the focus system extracts the best focus position (i.e., (4)), an offset is introduced outside the focus sensor for the measurement system. Referring now to Figure 8 In the _# generation according to the present invention, instead of adjusting the optical component as in the first embodiment, software correction can be performed on the signal applied to the actuator in the objective lens stage 63 by the focus controller (7). In the first embodiment, in step S81, the reference measurement is performed to determine that the focus is determined by the focus sensing configuration; the focus is required for the specific light beam used in the special measurement operation. (4) Shift. In the subsequent on-line scattering measurement operation, as indicated in step #, under the control of the processor PU, the focus controller 67 is then configured to provide a modified control signal 145019.doc -20-201118366, also That is, instead of making sms2 and so on, The difference between the offset values. This is used to control the actuator in the objective lens platform 63 to adjust the position of the objective lens system to (4) the best focus determined by the focus controller, taking into account the offset. It should be understood, however, that implementation of this embodiment requires a known relationship between the output of the focus sensor 61 and the actual linear displacement of the objective system, ideally a linear relationship, which will depend on a number of factors. Including the structure of the measured wafer w. It should be understood that regardless of the particular application or focus system, for the scatterometer sensor 18 or focus sensor 61 'for focus sensor and scatterometry sensor The correction of the offset between , , , and the dots will allow the (four) smaller focus of the best focus to be obtained. This will result in better alignment of the components of the scatterometer of the wafer positioning system described above, which will result in more accurate CD and /戍0V measurements. In addition, the better focus for measuring scattered radiation will also result in more accurate CD and/or OV measurements. A better focus will result in a sharper image for the alignment of the wafers by the wafer positioning system described above, resulting in a more J alignment. In the case of a 0V measurement, it is possible to choose where to measure throughout the crystal because the best focus will not depend on the crystal. It should also be understood that the possibility of adjustment for the offset allows for a better of the tenth of the focus sensor. Similarly, the sensor is not required to provide the best possible focus because it can be corrected afterwards. In addition, the scatterometry & t t H can be modified to make it possible, for example, to measure the spectrum produced by the poorly reflective surface by making it possible to vary the intensity of the incident shot. Offset correction will also enable the county to implement an alternative to the optical sensor described above 145019.doc -21 · 201118366 Focus Sensing ϋ (eg, Capacitive Sensor), but it will then be necessary to provide different Control System. When the capacitance sensor is used, the optimum focus position of the objective lens is determined in the adjustment procedure, and the capacitance sensor is used to determine the relative position of the wafer w and the objective lens 69. An offset is applied to the signal produced by the capacitive sensor to compensate for changes in the measurement characteristics between the adjustment procedure and the operation of the scatterometer. Although reference may be made specifically to the use of lithographic apparatus in 1C fabrication herein, it should be understood that the lithographic apparatus described herein may have other applications, such as manufacturing integrated optical systems, guidance for magnetic domain memory, and Detection patterns, flat panel displays, liquid crystal displays (LCDs), thin film heads, and the like. Those skilled in the art should understand that in the context of such alternative applications, any use of the "wafer" #"grain" in this document may be considered synonymous with the more general terms "substrate" and "target". . The substrates referred to herein may be processed before or after exposure, for example, in a coating development system (a tool that typically applies a layer of resist to the substrate and develops the exposed resist), a metrology tool, and/or a testing tool. Where applicable, the disclosures herein may be applied to 6Hai and other substrate processing facilities. In addition, the substrate can be treated more than once (for example) to form a multilayer 1C, such that the term substrate as used herein may also refer to a substrate that already contains a plurality of treated layers. The use of embodiments of the invention in the context of optical lithography may be specifically referenced above, but it should be understood that the invention may be used in other applications (eg, embossing lithography) and is not limited to optical when context permits Lithography. In imprint lithography, the configuration in the patterned device defines a pattern formed on the substrate that can be applied to the anti-g agent layer of the substrate by the patterning of the patterned device 145019.doc -22·201118366, On the substrate, the resist is cured by application of electromagnetic radiation, heat, pressure, or a combination thereof. After the resist is cured, the patterned device is removed from the photoresist ' to leave a pattern therein. As used herein, the terms "light shot" and "beam" are used to cover all types of electromagnetic light shots 'including ultraviolet (uv) radiation (for example, having or being about Naimi, 355 nm, 248 nm, 193) Nano, 157 nm or I% nanometer wavelengths) and extreme ultraviolet (bribet) radiation (for example, having a wavelength in the range of 5 nm to 2 nm); and particle beams (such as ion beams or bundle). The term "lens", when the context permits, may refer to any or a combination of various types of optical components, including refraction, reflection, magnetism, electromagnetic, and static.
電光學組件。 W u rr田邋奉發明之特定實施例 -，二你％解，可以 與所描述之方式不同的其他方式來實踐本發 言，本發明可採取如下形式：電腦程式，其含有描述如: 上所揭不之方法之機器可讀指令的一或多個序 儲存媒體（例如，半導體記憶 甘取貧料 存於其中之該電腦程式。 其具有儲 以上描述意欲係說明性而非限制性的。因此，Electro-optical components. W u rr 邋 邋 特定 特定 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明One or more sequential storage media of the machine readable instructions of the method (eg, the semiconductor memory is stored in the computer program. The storage of the above description is intended to be illustrative and not limiting. ,
此項技術者將顯而易見，可在不脫離 子於熟I 你个貺雕以下所闌明 利範圍之範缚的情況下對如所描述之本發 π專 【圖式簡單說明】 π修改。 圖1描繪微影裝置； 圖2描繪微影單元或叢集； 145019.doc -23- 201118366 圖3描繪第 一散射計； 圖4描繪第 二散射計； 圖5描繚展 計； 不感測胃平台及晶圓纟之細節#第三散射 圖6福繪併入於圖5所示之散射計中的示意性光學配置， 其係用於根據本發明之散射計之第—實施例中； ▲圖7為展示根據本發明之第一實施例的圖5及圖6之散射 計之操作的流程圖； 圖8為展示根據本發明之第二貫施例的圖5及圖6之散射 計之操作的流程圖。 【主要元件符號說明】 2 寬頻帶（白光）輻射投影儀/輻射源 4 分光計彳貞測器 10 光譜 11 背部投影式光瞳平面 12 透鏡系統 13 干涉滤光器 14 參考鏡面 15 顯微鏡接物鏡/透鏡系統/接物鏡系統/接物鏡 配置 16 部分反射表面/光束***器 17 偏振器 18 偵測器/散射計感測器/散射量測感測器/散射 計感測器系統 145019.doc 201118366 30 基板目標 51 基底框架 53 線性Υ平台 55 線性X平台 57 旋轉平台 59 晶圓台 61 焦點感測器 63 接物鏡平台 65 焦點照明系統 67 焦點控制器 69 透鏡/接物鏡 71 聚焦透鏡 73 鏡面 75 偵測器 77 偵測器 79 孔徑/針孔 81 孔徑 83 鏡面 85 焦平面 87 焦平面 AD 調整器 Β 輻射光束 BD 光束傳送系統 ΒΚ 烘烤板 145019.doc ·25· 201118366 c 目標部分 CH 冷卻板 CO 聚光器 DE 顯影器 IF 位置感測器 IL 照明系統/照明器 IN 積光器 I/Ol 輸入/輸出埠 1/02 輸入/輸出璋 LA 微影裝置 LACU 微影控制單元 LB 裝載盤 LC 微影單元 Ml 光罩對準標記 M2 · 光罩對準標記 MA 圖案化器件/光罩 MT 支撐結構/光罩台 PI 基板對準標記 P2 基板對準標記 PL 投影系統 PM 第一*** PU 處理單元/處理器 PW 第二*** RO 機器人 145019.doc -26- 201118366 sc 旋塗器 scs 監督控制系統 so 輻射源 TCU 塗布顯影系統控制單元 w 基板 WT 基板台 145019.doc -27-It will be apparent to those skilled in the art that the present invention can be modified as described above without departing from the scope of the invention. Figure 1 depicts a lithography apparatus; Figure 2 depicts a lithography unit or cluster; 145019.doc -23- 201118366 Figure 3 depicts a first scatterometer; Figure 4 depicts a second scatterometer; Figure 5 depicts a spirometer; And the details of the wafer crucible #third scattering diagram 6 is a schematic optical configuration incorporated in the scatterometer shown in FIG. 5, which is used in the first embodiment of the scatterometer according to the present invention; 7 is a flow chart showing the operation of the scatterometer of FIGS. 5 and 6 according to the first embodiment of the present invention; FIG. 8 is a view showing the operation of the scatterometer of FIGS. 5 and 6 according to the second embodiment of the present invention. Flow chart. [Main component symbol description] 2 Broadband (white light) radiation projector / radiation source 4 Spectrometer detector 10 Spectrum 11 Back projection diaphragm plane 12 Lens system 13 Interference filter 14 Reference mirror 15 Microscope objective lens / Lens System / Mirror System / Mirror Configuration 16 Partial Reflective Surface / Beam Splitter 17 Polarizer 18 Detector / Scatterometer Sensor / Scattering Measurer / Scatterometer Sensor System 145019.doc 201118366 30 Substrate target 51 Base frame 53 Linear Υ platform 55 Linear X platform 57 Rotary platform 59 Wafer table 61 Focus sensor 63 Mirror platform 65 Focus illumination system 67 Focus controller 69 Lens / objective lens 71 Focus lens 73 Mirror 75 Detection 77 Detector 79 Aperture / Pinhole 81 Aperture 83 Mirror 85 Focal plane 87 Focal plane AD adjuster 辐射 Radiated beam BD Beam transfer system 烘烤 Baking plate 145019.doc ·25· 201118366 c Target part CH Cooling plate CO Spotlight DE Developer IF Position Sensor IL Illumination System / Illuminator IN Accumulator I/Ol Input / Output埠1/02 Input/Output 璋LA lithography device LACU lithography control unit LB loading plate LC lithography unit Ml reticle alignment mark M2 · reticle alignment mark MA patterning device / reticle MT support structure / reticle stage PI substrate alignment mark P2 substrate alignment mark PL projection system PM first positioner PU processing unit / processor PW second positioner RO robot 145019.doc -26- 201118366 sc spin coater scs supervisory control system so radiation source TCU Coating development system control unit w substrate WT substrate stage 145019.doc -27-