2663TWF.DOC/005 經濟部中央標準局舅工消費合作社印裝 A7 B7 五、發明説明（f ) 本發明是有關於一種監測晶圓對準方法，且特別是有 關於一種以游標(venier)監測晶圓的對準方法。 微影(Photolithography)可以說是整個半導體製程中，最 舉足輕重的步驟之一，凡是與金氧半導體（Metal-Oxide-Semiconductor)元件的結構相關的，例如：各層薄膜的圖案 (Pattern)，及雜質（Dopants)的區域，都是由微影這個步驟來 決定的，因此通常以一個製程所需要經過的微影次數，或 是所需要的光罩數量，來表示這個製程的難易程度。此外， 整個半導體工業元件的積集度（Integration),是否能繼續的 往〇.25μιη以下更小的線寬進行，也端賴微影製程的發展， 所以微影的技術是很重要的。 而微影的技術係在曝光的步驟中，將光罩上的圖案，透 過光束傳遞到晶片表面的感光材料上。其中，光罩的目的 是在作圖案的轉移，所以若是光罩在置放上有任何偏移的 情況發生，都會使得圖案無法完整以及正確的轉移到晶片 表面的感光材料上。 請參照第1圖，習知技藝中，係在一晶圓100上形成一 或二個對準標記(alignment mark) 102，之後的第一光罩係利 用對準標記102進行對準晶圓1〇〇的工作，但在第一光罩 曝光後，並未有監測技術可以測知第一光罩曝光後之圖案 是否確實對準晶圓。而若是第一光罩形成的圖案已偏移晶 圓，則後續曝光之光罩圖案業已偏移，反而造成製程時間 上的浪費，更增加晶圓的耗損率。 有鑑於此，本發明的主要目的，就是在進行圖案曝光的 3 (請先閲讀背面之注意事項再填寫本頁)2663TWF.DOC / 005 Printed by A7 B7, Masonry Consumer Cooperatives, Central Standards Bureau, Ministry of Economic Affairs 5. Description of the Invention (f) The present invention relates to a method for monitoring wafer alignment, and in particular, to a method for monitoring with a venier Wafer alignment method. Photolithography can be said to be one of the most important steps in the entire semiconductor process. It is related to the structure of Metal-Oxide-Semiconductor elements, such as the pattern of each layer of thin film and impurities The area of (Dopants) is determined by this step of lithography. Therefore, the difficulty of this process is usually expressed by the number of lithography that a process needs to pass, or the number of photomasks required. In addition, whether the integration of the entire semiconductor industry components can be continued to a smaller line width of less than 0.25 μm depends on the development of the lithography process, so the technology of lithography is very important. In the lithography technology, the pattern on the photomask is transmitted to the photosensitive material on the wafer surface through the light beam during the exposure step. Among them, the purpose of the photomask is to transfer the pattern, so if any deviation in the placement of the photomask occurs, the pattern cannot be completely and correctly transferred to the photosensitive material on the wafer surface. Please refer to FIG. 1. In the conventional art, one or two alignment marks 102 are formed on a wafer 100, and the subsequent first photomask uses the alignment marks 102 to align the wafer 1. 〇〇 work, but after the first photomask exposure, there is no monitoring technology to determine whether the pattern after the first photomask exposure is indeed aligned with the wafer. If the pattern formed by the first mask has shifted from the wafer, the mask pattern of subsequent exposures has shifted, which will cause a waste of process time and increase the wear rate of the wafer. In view of this, the main purpose of the present invention is to perform pattern exposure 3 (Please read the precautions on the back before filling this page)
本紙張尺度適用中國國家標準（CNS) A4規格（21〇X?97公釐） 經濟部中央標率局貝工消費合作社印奴 2663TWF.DOC/005 六了 一 _—__ — 五、發明说明（> ) ~~~" 前後’在晶圓上各提供一游標，而藉由曝光前後二游標的 對準與否’判定圖案是否與晶圓或上一圖案對準，作爲製 程是否繼續進行的依據。 爲達上述之目的，本發明提供一種監測晶圓對準的方 法，係在未進行任何圖案曝光前，在晶圓上且與形成對準 標記同時’在對準標記旁形成一第一游標。之後，利用— 微影製程，在晶圓上形成一圖案，再於晶圓上形成一第二 游標。在此，圖案與第二游標經不同曝光步驟形成，因之， 若是第一游標與第二游標對齊，未有偏移，則可知以光罩 定義形成之圖案對準晶圓。反之，若是第一游標與第二游 標有偏移的情況產生，則可知圖案與晶圓亦發生偏移，故 可作爲製程是否繼續進行的判斷方式。 爲讓本發明之上述和其他目的、特徵、和優點能更明顯 易懂，下文特舉一較佳實施例，並配合所附圖式，作詳細 說明如下： 圖式之簡單說明： 第1圖係顯示一種習知技藝晶圓對準標記之示意圖； 第2A圖至第2C圖係顯示根據本發明較佳實施例監測 晶圓對準方法之示意圖； 第3圖爲第2B圖晶粒之局部放大圖；以及 第4圖爲第2C圖晶粒之局部放大圖。 其中，各圖標號之簡單說明如下： 100、200 :晶圓 102、202 :對準標記 4 本紙張尺度適用中國國家標準（CNS〉A4規格（210 X 297公釐） (請先閲讀背面之注意事項再填寫本頁) i^------------ο裝------，玎------®-------.—.--- 2663TWF.DOC/005 ^ B7 _ 五、發明説明（今） 204、208、212 :第一游標、第二游標、第三游標 205 :晶粒 (請先閱讀背面之注意事項再填寫本頁) 206、210 :第一圖案、第二圖案 207 :主要電路區 實施例 第2A圖至第2C圖係顯示根據本發明較佳實施例監測 晶圓對準方法之示意圖。 請參照第2A圖，在一晶圓200上形成對準標記202 ’ 且同時在離對準標記202 —距離d處形成第一游標204’而 對準標記202與第一游標204的距離係固定的，至少相距1 釐米。其中，對準標記202與第一游標204係在晶圓200 上同時曝光形成。 •經濟部中央標準局貝工消费合作社印絮 接著，請參照第2B圖，對準標記202與第一游標204 位於晶粒205a中，而主要電路區207位於與對準標記202 和第一游標204不同的晶粒205b中。以一第一光罩(未繪 示)進行一第一圖案206之微影製程而定義晶圓200,之後， 曝光第一圖案206,接著再進行另一微影製程曝光第二游標 208，因此第二游標208獨立於第一圖案206之形成。第3 圖爲第2B圖晶粒205a、205b之局部放大圖，第二游標208 與第一光罩之第一圖案206係在不同曝光步驟形成，由於 光罩並非在進行每一次的微影製程時均重新對準，故以第 一游標204與第二游標208之對齊程度判斷圖案與晶圓之 對準與否。因之若是第二游標208如第3圖所示與第一游 標2〇4對準，則可知第一光罩曝光之第一圖案206對準晶 5 本紙張尺度適用中國國家標準（CNS ) A4規格（210χ297公釐） 經濟部中央標準局貝工消費合作社印裝 2663TWF.DOC/005 A7 B7________ 五、發明説明（) — 圓200，而未引起偏移（Shift)的現象，因之可繼續進行後續 的製程。若是發現第二游標208與第一游標204有偏移的 狀況產生，而可及早得知第一圖案206與晶圓200亦偏移， 因之減少晶圓損失的機率。 之後，請參照第2C圖，利用一第二光罩(未繪不)進行 一第二圖案210之微影而定義晶圓200，在曝光第二圖案 210後，再以另一微影製程曝光第三游標212 ’而第二圖案 210與第三游標212係獨立曝光形成。其中’第4圖爲第 2C圖晶粒205a、2〇5b之局部放大圖，則若是第三游標212 如第4圖所示與第二游標208重疊，可知第二光罩曝光之 第二圖案210對準第一光罩之第一圖案206,而未引起偏移 (Shift)的現象，因之可繼續進行後續的製程。若是發現第三 游標212與第二游標208有偏移的狀況產生，同時即知第 二圖案210與晶圓200亦偏移。 重複上述步驟，則可經由不同層游標的對準與否，監測 得各層圖案是否偏移，因之可及早發現對準誤差，降低晶 圓報廢機率，亦可縮短製程時間。 雖然本發明已以一較佳實施例揭露如上，然其並非用以 限定本發明，任何熟習此技藝者，在不脫離本發明之精神 和範圍內·，當可作各種之更動與潤飾，因此本發明之保護 範圍當視後附之申請專利範圍所界定者爲準。 6 本紙張尺度適用中國國家標準（CNS ) A4規格（210X29*7公釐） ---------裝------訂-------K) (請先閲讀背面之注意事項再填寫本頁)This paper size applies the Chinese National Standard (CNS) A4 specification (21 × 97 mm). The Central Standards Bureau of the Ministry of Economic Affairs, Shellfish Consumer Cooperative, India, 2663TWF.DOC / 005. >) ~~~ " Before and after 'provide a vernier on the wafer, and determine whether the pattern is aligned with the wafer or the previous pattern by the alignment of the two verniers before and after exposure' as the process continues Basis. To achieve the above object, the present invention provides a method for monitoring wafer alignment by forming a first vernier on the wafer at the same time as the formation of the alignment mark 'before the pattern exposure. After that, a pattern is formed on the wafer by using a lithography process, and then a second cursor is formed on the wafer. Here, the pattern and the second cursor are formed through different exposure steps. Therefore, if the first cursor is aligned with the second cursor without offset, it can be known that the pattern formed by the mask definition is aligned with the wafer. Conversely, if the first cursor and the second cursor are offset, it can be known that the pattern and the wafer are also offset, so it can be used as a method of judging whether the process continues. In order to make the above and other objects, features, and advantages of the present invention more comprehensible, a preferred embodiment is given below in conjunction with the accompanying drawings for detailed description as follows: Brief description of the drawings: FIG. 1 FIG. 2A to 2C are schematic diagrams illustrating a method for monitoring wafer alignment according to a preferred embodiment of the present invention; FIG. 3 is a part of a die in FIG. 2B Enlarged view; and FIG. 4 is a partial enlarged view of the grains of FIG. 2C. Among them, the brief description of each icon number is as follows: 100, 200: Wafer 102, 202: Alignment mark 4 This paper size applies to Chinese national standards (CNS> A4 specification (210 X 297 mm)) (Please read the note on the back first Please fill in this page for more information) i ^ ------------ ο Install ------, 玎 ------ ® -------.--.--- 2663TWF.DOC / 005 ^ B7 _ V. Description of the invention (today) 204, 208, 212: First cursor, second cursor, third cursor 205: Grain (Please read the precautions on the back before filling this page) 206 , 210: first pattern, second pattern 207: Embodiments of the main circuit area Figs. 2A to 2C are schematic diagrams showing a method for monitoring wafer alignment according to a preferred embodiment of the present invention. Please refer to Fig. 2A. An alignment mark 202 'is formed on the wafer 200 and a first cursor 204' is formed at a distance d from the alignment mark 202. The distance between the alignment mark 202 and the first cursor 204 is fixed, at least 1 cm away. The alignment mark 202 and the first cursor 204 are formed on the wafer 200 at the same time by exposure. • Printed by the Shellfish Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs. Please refer to Figure 2B. The alignment mark 202 and the first vernier 204 are located in the die 205a, and the main circuit area 207 is located in a different die 205b than the alignment mark 202 and the first vernier 204. It is performed with a first photomask (not shown). A wafer 200 is defined by a lithography process of a first pattern 206. After that, the first pattern 206 is exposed, and then another lithography process is performed to expose the second cursor 208. Therefore, the second cursor 208 is independent of the formation of the first pattern 206. Figure 3 is a partial enlarged view of the grains 205a and 205b in Figure 2B. The second cursor 208 and the first pattern 206 of the first photomask are formed in different exposure steps. Since the photomask is not performing each lithography During the process, they are realigned. Therefore, the alignment between the first cursor 204 and the second cursor 208 is used to determine whether the pattern is aligned with the wafer. Therefore, as shown in FIG. 〇4 alignment, it can be known that the first pattern 206 exposed by the first photomask is aligned with the crystal. 5 This paper size applies the Chinese National Standard (CNS) A4 specification (210x297 mm). Printed by the Bayer Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs. 2663TWF .DOC / 005 A7 B7________ V. Description of Invention () Circle 200 without causing a shift (Shift) phenomenon, so the subsequent processes can continue. If it is found that the second cursor 208 and the first cursor 204 are offset, the first pattern 206 can be known early It is also offset from the wafer 200, thereby reducing the chance of wafer loss. After that, please refer to FIG. 2C, and use a second photomask (not shown) to perform a lithography of a second pattern 210 to define the wafer 200. After exposing the second pattern 210, the third cursor 212 'is exposed by another lithography process, and the second pattern 210 and the third cursor 212 are formed by independent exposure. Among them, the “4th image” is a partial enlarged view of the grains 205a and 20b in FIG. 2C. If the third cursor 212 overlaps with the second cursor 208 as shown in FIG. 4, it can be seen that the second pattern of the second photomask is exposed. 210 is aligned with the first pattern 206 of the first photomask without causing a shift (Shift) phenomenon, so that subsequent processes can be continued. If it is found that the third cursor 212 is offset from the second cursor 208, it is known that the second pattern 210 and the wafer 200 are also offset. By repeating the above steps, the alignment of the cursors in different layers can be used to monitor whether the pattern of each layer is shifted, so that alignment errors can be detected early, the probability of wafer scrapping can be reduced, and the process time can be shortened. Although the present invention has been disclosed as above with a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make various changes and decorations without departing from the spirit and scope of the present invention. The protection scope of the present invention shall be determined by the scope of the attached patent application. 6 This paper size is applicable to China National Standard (CNS) A4 specification (210X29 * 7mm) --------- Installation ------ Order ------- K) (Please read first (Notes on the back then fill out this page)