587200 A7 -—-.____ B7 _ __ 五、發明説明（） 發明領域： 本發明係有關於一種改善曝光區域内（Intrafield)之疊 對精度（Overlay Accuracy)的方法，特別是有關於一種以臨 場（In-situ)方式修正曝光區域内之疊對精度的方法。 發明背景： • 在積體電路（IC)之製作過程中，微影技術是影響線寬之 臨界尺寸的關鍵技術，而疊對精度則是控制微影技術的關 鍵準則之一。在微影過程中，疊對誤差的產生乃係由於晶 圓在製程中，因上下圖案層對準產生偏移所導致。由於， 叠對誤差會導致晶胞面積增加。因此，若能有效提高疊對 精度’即可縮小晶胞面積，如此一來便可在同一片晶圓上 製造出數量更多之晶胞，不僅可降低晶胞製造成本，更可 提高晶胞之產能。 疊對誤差主要可分成兩類，其一為曝光區域間 (InterHeld)之誤差，另一則為曝光區域内之誤差。曝光區 域間之疊對誤差屬局部，同一晶圓上的每一晶片並不一定 都會有曝光區域間之疊對誤差產生。而曝光區域内之叠對 誤差則屬於較全面性的，同一晶圓上的每一晶片皆可能會 •產生曝光區域内之疊對誤差。目前，對於微影製程之昼對 誤差的控制’大致上係以掃瞒機（Scanner)之對準系統來進 行曝光區域間之疊對誤差的修正，以及利用先前一批晶圓 運用光罩四周的交互框（Box-in-box)對準記號所得之叠對 結果來進行曝光區域間與曝光區域内的 本紙張尺度適用中國國家標準(CNS)A4規格(210X297公釐) (請先閲讀背面之注意事項再填寫本頁) 訂· § 經濟部智慧財產局員工消費合作社印製 587200 A7 B7 五、發明説明（） 疊對修正。 (請先閲讀背面之注意事項再填寫本頁) 然而，曝光區域内之疊對誤差的修正係採用前授的方 式’為一種消極的方式。因而，常使得晶圓之上下層間之 疊對誤差過大不符製程需求，除了導致產品良率不佳外， 更會使得重做率（Rework Rate)提高，進而造成人力與材 料資源的浪費，增加製程成本負擔。 發明目的及概述： 鑒於上述之發明背景中，缺乏臨場監控以修正曝光區 域内之疊對誤差的有效方法，而造成產品良率不佳，導致 高重做率，耗費更多的人力資源與成本。 因此’本發明的主要目的之一就是在提供一種以臨場 方式即時修正曝光區域内之疊對誤差的方法，其係在光罩 上與切割巷對應處額外加入1至3組對準標記圖案。藉由 這些額外增加之對準標記圖案，可在利用此光罩進行曝光 前，先行完成精確的對準。因此，可大幅改善曝光區域内 之疊對精度，提高產品良率。 本發明之再一目的就是因為可臨場監控並即時修正曝 光區域内之疊對誤差，而獲得極佳之疊對精度。因此，可 大幅降低重做率，進而減少材料及人力資源的浪費，有效 降低製程成本。 經濟部智慧財產局員工消費合作社印製 根據以上所述之目的，本發明更提供了 一種改善曝光 區域内之疊對精度的方法，適用於一晶圓上製作複數個晶 胞，且此改善曝光區域内之疊對精度的方法至少包括：提 本紙張尺度適用中國國家標準(CNS)A4規格(210X 297公釐) 587200 、發明說明（） (請先閱讀背面之注意事項再填寫本頁) 供一第一光罩，其中此第一光罩至少包括一結構圖案以及 複數個對準標記圖案，且這些對準標記圖案的數量成一預 °又組數，且此預設組數介於2至4之間。再利用上述之第 光罩於晶圓上形成晶胞之一結構層以及複數個對準標 其中此結構層之位置對應於第一光罩之結構圖案的位 置且對準標記之位置對應於第一光罩之對準標記圖案的 位置。接著，利用一曝光機台之一對準系統對上述之晶圓 上的對準標記進行一臨場對準步驟，藉以獲得一曝光區域 内叠對參數。然後，利用所獲得之曝光區域内叠對參數對 一第二光罩進行_臨場校正步驟。完成第三光罩之臨場校 正步驟後，即可透過上述之曝光冑台進行另一結構層的製 作。如此-來，利用臨場對準透過第一晶圓形成於晶圓上 之對準標記，可臨場校正後續所使用之光罩，而確保後續 製作之各結構層皆可正確地曝準。 由於，上述之第一光罩上之對準標記圈案比習知&少 多一組，最多增加3組，因此可在_帛_ 了弟一先罩進行曝光前， 使對準系統精確地對準晶圓上之對準 了半铩圮，而獲得高準確 度之曝光區域内疊對參數。如此一來， 采’即可根據此高準確 度之曝光區域内疊對參數對第二光罩推 車進仃臨場校正，精確 經濟部智慧財產局員工消費合作社印製 地完成曝光區域内之各層疊對動作。 於疋’便可臨場監控 曝光區域内之疊對誤差，以利即時修 ’而使曝光區域内 之疊對精度獲得有效改善。 發明詳1«說明： 本紙張尺度適用中國國家標準(CNS)A4規格(210x297公楚) 587200587200 A7 -—-.____ B7 _ __ 5. Description of the invention () Field of the invention: The present invention relates to a method for improving the overlay accuracy (Overlay Accuracy) in the exposure area (Intrafield), and in particular to a method of using the presence (In-situ) method to correct the overlap accuracy in the exposure area. Background of the Invention: • During the fabrication of integrated circuits (ICs), lithography is a key technology that affects the critical dimension of line width, and overlay accuracy is one of the key criteria for controlling lithography. During the lithography process, the stacking error is caused by the deviation of the crystal circle in the manufacturing process and the alignment of the upper and lower pattern layers. Due to the overlap error, the cell area increases. Therefore, if the stacking accuracy can be effectively improved, the cell area can be reduced, so that more cell units can be manufactured on the same wafer, which can not only reduce the cell manufacturing cost, but also increase the unit cell. Capacity. Overlay errors can be divided into two categories, one is the error between the exposed areas (InterHeld), and the other is the error within the exposed areas. The overlap error between the exposure areas is local, and each wafer on the same wafer does not necessarily have the overlap error between the exposure areas. The overlap error in the exposure area is more comprehensive, and each wafer on the same wafer may produce a stack error in the exposure area. At present, the control of the error during the lithography process is generally based on the alignment system of the scanner to correct the overlap error between the exposure areas, and to use the previous batch of wafers around the photomask. The box-in-box alignment results obtained by aligning the mark of the box-in-box are used to measure the paper size between the exposure areas and within the exposure area. This paper applies the Chinese National Standard (CNS) A4 specification (210X297 mm) Please pay attention to this page before filling in this page) § § Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 587200 A7 B7 V. Description of the invention () Overlap correction. (Please read the precautions on the back before filling out this page) However, the correction of the stacking error in the exposure area is a negative method using the pre-determined method. Therefore, the stack error between the upper and lower layers of the wafer is often too large to meet the requirements of the process. In addition to the poor product yield, the rework rate will be increased, which will cause a waste of human and material resources and increase the process. Cost burden. Object and summary of the invention: In view of the above background of the invention, there is a lack of effective methods of on-site monitoring to correct overlapping errors in the exposure area, resulting in poor product yields, resulting in high redo rates, which consume more human resources and costs . Therefore, one of the main objects of the present invention is to provide a method for correcting the overlap error in the exposure area in a real-time manner, which is to add 1 to 3 sets of alignment mark patterns on the mask corresponding to the cutting lanes. With these additional alignment mark patterns, precise alignment can be completed before exposure with this mask. As a result, the overlap accuracy in the exposed area can be greatly improved, and the product yield can be improved. Yet another object of the present invention is to obtain excellent overlay accuracy because the overlay error within the exposure area can be monitored and corrected in real time. Therefore, the redo rate can be greatly reduced, thereby reducing the waste of materials and human resources, and effectively reducing the process cost. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs According to the above-mentioned purpose, the present invention further provides a method for improving the overlap accuracy in the exposure area, which is suitable for making a plurality of cells on a wafer, and this improves the exposure The method of overlapping accuracy in the area at least includes: the paper size of the paper is applicable to the Chinese National Standard (CNS) A4 specification (210X 297 mm) 587200, the description of the invention () (please read the precautions on the back before filling this page) for A first photomask, wherein the first photomask includes at least a structural pattern and a plurality of alignment mark patterns, and the number of the alignment mark patterns is a pre-degree and a group number, and the preset group number is from 2 to Between 4. Then, the first photomask is used to form a structural layer of the unit cell on the wafer and a plurality of alignment marks. The position of this structural layer corresponds to the position of the structural pattern of the first photomask and the position of the alignment mark corresponds to the first The position of the alignment mark pattern of a photomask. Then, an alignment system on an exposure machine is used to perform an on-site alignment step on the above-mentioned alignment marks on the wafer, so as to obtain an overlapped parameter in the exposure area. Then, a _field correction step is performed on a second photomask by using the obtained overlapped parameters of the exposure area. After completing the on-the-spot correction step of the third photomask, another structural layer can be produced through the exposure platform described above. In this way, the alignment mark formed on the wafer through the first wafer by using the in-situ alignment can be used to correct the subsequent masks in the field and ensure that the subsequent fabrication layers can be correctly exposed. Because the alignment mark circle on the first photomask mentioned above is one set less than the conventional one, and up to 3 sets can be added, the alignment system can be made precise before the first mask is exposed. The alignment on the wafer has been aligned for a half a while, and superimposed parameters in the exposed area with high accuracy are obtained. In this way, according to this high-accuracy overlay parameter in the exposure area, the second mask cart can be corrected on the spot, and the consumer goods cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs can print and complete each of the exposure areas. Cascading pair action. In 疋 ’, you can monitor the overlap error in the exposure area on the spot to facilitate real-time repair, and effectively improve the overlay accuracy in the exposure area. Invention Details 1 «Explanation: This paper size is applicable to China National Standard (CNS) A4 (210x297 Gongchu) 587200
五、發明説明（ 本發明揭露一種改善曝光區域内之疊對精度的方 法’其係在光罩上額外增加數組對準標記圖案。藉由這些 (請先閲讀背面之注意事項再填寫本頁) 對準標記圖案，可在進行曝光步驟前，使光罩與晶圓精確 對準。如此一來，即可臨場修正曝光區域内之疊對誤差。 因此’不僅可達到提高曝光區域内之疊對精度的目的，更 可提同製程可靠度以及產品良率。為了使本發明之敘n 加詳盡與元備，可參照下列描述並配合第1圖至第3圖之 圖示。 經濟部智慧財產局員工消費合作社印製 请參照第1圖，第1圖係繪示本發明之一較佳實施例 之光罩的上視圖。光罩100上至少包括元件圖案區1〇2, 在此元件圖案區102中設置有元件之結構層佈局圖案（未繪 示）。另外，在元件圖案區102外圍之光罩1〇〇上則設置有 一組對準標記圖案104、一組對準標記圖案1〇6、一組對準 標記圖案108、以及一組對準標記圖案11〇，如第i圖所示。 其中，對準標記圖案1〇4、對準標記圖案1〇6、對準標記圖 案108、以及對準標記圖案11〇可例如為位置對應於晶圓 之切割巷的㈣巷料標記圖案。此外，對準標記圖案 104、對準標記囷案1〇6、對準標記圊案1〇8、以及對準標 記圖案110可例如採用由艾司摩爾股份有限公司（asml)所 提供之SSPMs型對準標記圖案、sspM8〇型對準標記圖 案、SSPM8.8型對準標記㈣、或者隨型對準標記圖案。 在本發明之較佳實施例中，光罩1〇〇包括4組對準標記圖 案’較習知光罩多3組對準標記圖案。V. Description of the Invention (The present invention discloses a method for improving the overlay accuracy in the exposure area, which is to add an additional array of alignment mark patterns on the photomask. By these (please read the precautions on the back before filling this page) The alignment mark pattern can accurately align the photomask and the wafer before the exposure step. In this way, the overlap error in the exposed area can be corrected on the spot. Therefore, not only can the overlap in the exposed area be improved The purpose of accuracy can also refer to the reliability of the process and the yield of the product. In order to make the description of the present invention more detailed and prepared, you can refer to the following description and cooperate with the diagrams in Figures 1 to 3. Intellectual Property of the Ministry of Economic Affairs Printed by the Bureau ’s consumer cooperative, please refer to FIG. 1, which is a top view showing a photomask according to a preferred embodiment of the present invention. The photomask 100 includes at least a component pattern area 102, where the component pattern The structure layer layout pattern (not shown) of the component is set in the area 102. In addition, a set of alignment mark patterns 104 and a set of alignment mark patterns 1 are provided on the mask 100 on the periphery of the component pattern area 102. 6, one A set of alignment mark patterns 108 and a set of alignment mark patterns 11 are shown in Fig. I. Among them, the alignment mark pattern 104, the alignment mark pattern 106, the alignment mark pattern 108, and the alignment mark pattern 108 The quasi-mark pattern 11 may be, for example, a mark pattern of a material in a position corresponding to a cut lane of a wafer. In addition, the alignment mark pattern 104, the alignment mark pattern 106, the alignment mark pattern 108, and The alignment mark pattern 110 may be, for example, an SSPMs type alignment mark pattern, an sspM80 type alignment mark pattern, an SSPM8.8 type alignment mark 提供, or a random alignment provided by Asml Corporation (asml). Marking Patterns In a preferred embodiment of the present invention, the photomask 100 includes 4 sets of alignment mark patterns, which are 3 more sets of alignment mark patterns than conventional photomasks.
587200 A7 B7 五、發明説明（） 接著’請參照第2圖，第2圖係繪示本發明之一較佳 實施例之另一光罩的上視圖。光罩200上至少包括元件圖 (請先閲讀背面之注意事項再填寫本頁) 案區202 ,且在此元件圖案區2〇2中設置有元件之結構層 佈局圖案（未緣示）。 i 經濟部智慧財產局員工消費合作社印製 本發明之進行請參照第3圖所繪示本發明較佳實施例 之改善曝光區域内之疊對精度的流程圖。首先，如同步驟 3 00所述，提供第一光罩，以利於晶圓上製作記憶晶胞 (Memory Cell)，例如框型（Frame)晶胞，其中第一光罩可採 用例如第1圖所示之光罩丨〇〇。接著，如同步驟3 所述， 於晶圓上先以例如沉積方式形成一層第一材料層，再以例 如塗佈方式於所沉積之第一材料層上覆蓋一層光阻層。此 光阻層形成後，於一曝光機台上透過光罩1〇〇對晶圓上之 光阻層進行曝光，藉以將光罩100上之元件圖案區1〇2上 之佈局圖案以及元件圖案區i 〇2外圍之對準標記圖案 104、對準標記圖案1〇6、對準標記圖案1〇8、以及對準標 記圖案110轉移至光阻層上。曝光後之光阻層，經例如顯 影以及蚀刻#步驟|，而纟晶圓丨之第一材料層中形成第 一結構層以及多個對準標記，並暴露出部分之晶圓。第一 .結構層以及對準標記形成後，將剩餘之光阻層去除。其中， 第一結構層係由元件圖案區102上之佈局圖案所轉移而 成，對準標記則包括由對準標記圖案1〇4所轉移而成之對 準標記、對準標記圖案106所轉移而成之對準標記、對準 標記囷案108所轉移而成之對準標記 '以及對準標記圖案 6 本紙張尺度適用中國國家標準(CNS)A4規格(210X297公釐) 587200 A7 B7 五、 發明説明（ 110所轉移而成之對準標記。在本發明之一實施例中，所 ^用之曝光機台係由艾司摩爾股份有限公司所提供，且曝 光機台所使用之對準系統係為艾司摩爾股份有限公司所提 供之雅典娜（ATHENA)系統。 於第一結構層以及對準標記形成後，如同步驟3〇4所 述’利用例如上述之曝光機台中的對準系統，以臨場方式， 對形成於晶圓上之曝光區域内對準標記進行對準步驟，而 獲得臨場曝光區域内疊對參數，以供後續之光罩的疊對校 正用。 完成晶圓上之對準標記的對準步驟後，提供第二光 罩’用以在第一結構層上製作另一結構層。其中，第二光 罩可例如採用第2圖所示之光罩2〇〇。此另一結構層之製 作係先以例如沉積的方式形成第二材料層覆蓋在上述之第 一結構層以及對準標記上，再利用例如塗佈的方式形成一 層光阻層覆蓋在所沉積之第二材料層上。接著，在透過光 罩200進行曝光步驟前，先行利用之前藉由對準第一材料 層上之對準標記所獲得之曝光區域内疊對參數對此光罩 200進行臨場校正步驟，藉以校正光罩2〇〇之放大倍率、 旋轉角度、移動等曝光區域内之疊對參數，使光罩2〇〇之 圖案經轉移後可準確地疊合在第一結構層上，如同步驟3〇6 所述。 完成疊對校正之光罩200後，即可用以進行曝光步驟， 包括使用上述之曝光機台，並透過光罩2〇〇對第二材料層 .................訂.........Φ (%.先閲讀背面之注意事項再填寫本頁} 經濟部智慧財產局員工消費合作社印製587200 A7 B7 V. Description of the invention () Next, please refer to FIG. 2, which is a top view showing another photomask according to a preferred embodiment of the present invention. The photomask 200 includes at least a component diagram (please read the precautions on the back before filling out this page) in the project area 202, and a component layer layout pattern (not shown) is set in this component pattern area 202. i Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. Please refer to Figure 3 for the implementation of the present invention. First, as described in step 300, a first photomask is provided to facilitate the fabrication of a memory cell, such as a frame cell, on the wafer. The first photomask can be, for example, as shown in FIG. 1. Shown the mask 丨 〇〇. Next, as described in step 3, a first material layer is first formed on the wafer by, for example, deposition, and then a photoresist layer is covered on the first material layer by, for example, coating. After the photoresist layer is formed, the photoresist layer on the wafer is exposed through a mask 100 on an exposure machine, so that the layout pattern and the element pattern on the element pattern area 102 on the mask 100 are exposed. The alignment mark pattern 104, the alignment mark pattern 106, the alignment mark pattern 108, and the alignment mark pattern 110 on the periphery of the area 〇2 are transferred to the photoresist layer. After the exposed photoresist layer, for example, development and etching steps, a first structure layer and a plurality of alignment marks are formed in the first material layer of the wafer, and a part of the wafer is exposed. First, after the structure layer and the alignment mark are formed, the remaining photoresist layer is removed. The first structure layer is transferred from the layout pattern on the element pattern area 102, and the alignment mark includes the alignment mark transferred from the alignment mark pattern 104 and the transfer mark pattern 106. Alignment mark formed by alignment mark, alignment mark transferred from alignment mark case 108, and alignment mark pattern 6 This paper size applies to China National Standard (CNS) A4 specification (210X297 mm) 587200 A7 B7 V. DESCRIPTION OF THE INVENTION The alignment mark transferred from 110. In one embodiment of the present invention, the exposure machine used is provided by Esmol, and the alignment system used by the exposure machine is Athena system provided by Esmol. Co., Ltd. After the first structure layer and the alignment mark are formed, use the alignment system in the exposure machine as described in step 304 to The on-site method performs an alignment step on the alignment marks formed in the exposure area on the wafer to obtain the overlay parameters in the on-site exposure area for subsequent overlay correction of the photomask. Alignment on the wafer is completed After the noted alignment step, a second photomask is provided to make another structural layer on the first structural layer. Among them, the second photomask can be, for example, the photomask 200 shown in FIG. 2. A structure layer is produced by first depositing a second material layer over the first structure layer and the alignment mark, for example, by deposition, and then forming a photoresist layer over the deposited second layer by, for example, coating. On the material layer. Then, before performing the exposure step through the mask 200, the on-site correction step of the mask 200 is performed using the overlapping parameters in the exposure area obtained by aligning the alignment marks on the first material layer. By correcting the overlay parameters in the exposure area such as the magnification, rotation angle, and movement of the mask 200, the pattern of the mask 200 can be accurately superimposed on the first structure layer after the transfer, as in the steps As described in 30.6. After completing the pair of correction masks 200, it can be used to perform the exposure step, including using the above-mentioned exposure machine, and passing the mask 200 to the second material layer ... .......... Order ......... Φ (%. Notes on the page and then fill in} Ministry of Economic Affairs Intellectual Property Office employees consumer cooperatives printed
五 、發明說明（ 上之光阻層進行曝光，藉以將光罩200之元 =佈局圓案轉移至第二材料層上之光阻層上。完成案第[二： 、斗層上之光阻層的曝光步驟，並經例如顯影以及蝕刻等步 ’可去除部分之第二材料層，以在晶圓上之第二材料 形成第二結構層，並使得第二結構層疊對於第一結構 層上。第二結構層形成後，接著剝除剩下之光阻層。其中， 結構層係由元件圖案區202上之佈局圖案所轉移而 發值得注意的一點是本發明所使用之第一光罩上之對準 標記圖案的組數可僅比習知光軍之1组對準標記圖案多i 組’至多可比習知光軍多3 t组’也就是說，本發明所使用 之第—光罩的對準標記圖案的組數較佳是介於2組至今粗 之間，並不限於以上所述。 …" •因此，本發明之一特徵為本發明所使用之光罩的對準 ^記囷案至少較習知所使用之光罩的對準標記圖案多】 組如此一來，將晶圓送入曝光機台以進行曝光步驟前， 光罩上所增加之對準標記圖案可使光罩以臨場的方式，更 輕易且更精確地對準晶圓，而不需一邊進行曝光一邊調整 光罩才能完成晶圓上之所有晶片的曝光。 本發明之一優點就是因為可利用光罩上額外增加之^ 至3組切割巷對準標記圖案，而在進行晶圓之曝光步驟 前，相當輕易地就可使光罩與晶圓獲得高精確的對準。因 此，可達到改善曝光區域内之疊對精度的目的，而大幅提 本紙張尺度適财S國準(CNS)A4規格⑽χ 297公楚） 587200 A7 B7 五、發明説明（） 高產品良率。 (請先閲讀背面之注意事項再填寫本頁) 本發明之另一優點就是因為藉由光罩上所額外加入之 切割巷對準標記圖案，可臨場監控並即時修正曝光區域内 之疊對誤差，而使晶圓上之結構層獲得高精度之疊對。因 此，可降低重做率，進而減少資源的浪費，達到降低製程 成本的目的。 如熟悉此技術之人員所瞭解的，以上所述僅為本發明 之較佳實施例而已，並非用以限定本發明之申請專利範 圍；凡其它未脫離本發明所揭示之精神下所完成之等效改 變或修飾，均應包含在下述之申請專利範圍内。 圈式簡單說明： 本發明的較佳實施例已於前述之說明文字中辅以下列 圖形做更詳細的闡述，其中： 第1圖係繪示本發明之一較佳實施例之一光罩的上視 面 · 圃， 第2圊係繪示本發明之一較佳實施例之另一光罩的上 視圊；以及 第3囷係繪示本發明較佳實施例之改善曝光區域内之 *疊對精度的流程圖。 經濟部智慧財產局員工消費合作社印製 圈就對照說明： 100 光罩 102 元件圖案區 104 對準標記圖案 106 對準標記圖案 108 對準標記圖案 110 對準標記圖案 9 本紙張尺度適用中國國家標準(CNS)A4規格(210X297公釐) 587200 A7 __________B7_ 五、發明説明（） 200 光罩 202 元件圖案區 300 提供第一光罩 302 形成結構層以及對準標記 304 進行臨場對準步驟 306 進行臨場校正步驟 (請先閲讀背面之注意事項再填寫本頁) 、τ i 經濟部智慧財產局員工消費合作社印製 本紙張尺度適用中國國家標準(CNS)A4規格(210X297公釐)V. Description of the invention (The photoresist layer on the top is exposed, so that the element of the mask 200 = layout circle is transferred to the photoresist layer on the second material layer. The second part of the case is completed. Layer exposure step, and through steps such as development and etching, a portion of the second material layer can be removed to form a second structure layer from the second material on the wafer, and the second structure is stacked on the first structure layer. After the second structure layer is formed, the remaining photoresist layer is then stripped. Among them, the structure layer is transferred by the layout pattern on the element pattern area 202 and it is worth noting that the first photomask used in the present invention is The number of sets of alignment mark patterns may be only i groups more than one set of alignment mark patterns of the conventional light army, 'at most 3 t groups of more than the conventional light army', that is, the alignment of the first mask used in the present invention The number of groups of the mark pattern is preferably between 2 and up to now, and is not limited to the above. Therefore, one feature of the present invention is the alignment of the photomask used in the present invention. At least more alignment mark patterns than the masks used in the past In this way, before the wafer is sent to the exposure machine to perform the exposure step, the alignment mark pattern added on the mask can make the mask more easily and accurately align the wafer in the field. It is not necessary to adjust the mask while performing exposure to complete the exposure of all the wafers on the wafer. One advantage of the present invention is that it can use the additional ^ to 3 sets of cutting lanes to align the mark patterns on the mask, and it is in progress. Before the wafer exposure step, the mask and wafer can be aligned with high precision quite easily. Therefore, the purpose of improving the overlay accuracy in the exposure area can be achieved, and the paper size can be greatly improved. Standard (CNS) A4 specifications (⑽χ 297 Chu) 587200 A7 B7 5. Description of the invention () High product yield. (Please read the precautions on the back before filling this page) Another advantage of the present invention is that by using the cutting lane alignment mark pattern added on the photomask, you can monitor the scene and correct the overlap error in the exposure area in real time. , So that the structural layers on the wafer can obtain high-precision stacking pairs. Therefore, the redo rate can be reduced, thereby reducing the waste of resources and achieving the purpose of reducing process costs. As will be understood by those familiar with this technology, the above descriptions are merely preferred embodiments of the present invention, and are not intended to limit the scope of patent application for the present invention; all others completed without departing from the spirit disclosed by the present invention, etc. Effective changes or modifications should be included in the scope of patent application described below. Brief description of the circle method: The preferred embodiment of the present invention has been described in more detail in the preceding explanatory text with the following figures, where: FIG. 1 is a diagram showing a photomask of one of the preferred embodiments of the present invention. Top view · The second line is a top view of another photomask according to a preferred embodiment of the present invention; and the third line is a view within an improved exposure area of a preferred embodiment of the present invention * Flow chart for overlay accuracy. The printed description circle of the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs will be compared with the description: 100 photomask 102 element pattern area 104 alignment mark pattern 106 alignment mark pattern 108 alignment mark pattern 110 alignment mark pattern 9 This paper standard applies to Chinese national standards (CNS) A4 specification (210X297 mm) 587200 A7 __________B7_ V. Description of the invention 200 Photomask 202 Element pattern area 300 Provide the first photomask 302 to form a structural layer and alignment marks 304 Perform field alignment step 306 Perform field correction Steps (please read the precautions on the back before filling this page), τ i Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs This paper is sized for the Chinese National Standard (CNS) A4 (210X297 mm)