200846703 九、發明說明： v 【發明所屬之技術領域】 本發明係有關於影像感測器微透鏡之製作方法，尤指影 像感测器之微透鏡陣列之製作方法。 【先前技術】 隨著數位相機、電子掃瞄產品不斷地開發與成長，市場 φ 上對景夕像感測元件之需求隨之持續增加，目前常用的影像 感測為包含有電荷|馬合感測器（charge C0Upietj device，CCD sensor)以及互補式金氧半導體影像感測器（c〇mpiementary metal oxide semiconductor，CMOS image sensor，CIS)兩大 類。而微透鏡(micro-lens)則係製作於該等影像感測器上， 用來控制光線行進的方向，以便將入射光聚合入射至光學 感測兀件如感光二極體(photodiode)等，藉以提高影像感測 器之感光度。 在習知技術中，微透鏡係採用感光性之光阻作為材料， 在經過烘烤(melting bake)製程之後，形成微透鏡所需之圓 滑曲面。請參閱第1圖至第3圖，第！圖至第3圖乃一習 知之微透鏡陣列製作方法之示意圖。請參閱第〗圖，首先 提供一半導體基底10，半導體基底10中形成有感光區域 12以及感光元件14，例如電荷耦合裝置（CCD)或者互補式 金氧半導體(CMOS)影像感應器等。另有透光之介電層π 200846703 形成於半導體基底10上；而介電層16上則係形成有一彩 色濾光陣列18，彩色濾光陣列18中之每一彩色濾光層單 元皆分別對應於一感光區域12，此外尚有一透光之平坦層 20形成於彩色濾光陣列18上。而如第1圖所示，隨後係 於平坦層20上形成一由光阻構成之微透鏡材料層30。 請參閱第2圖與第3圖。接下來，係利用一習知之微影 製程圖案化微透鏡材料層30，而形成具有複數個光阻凸塊 32之陣列34，且各光阻凸塊32係分別對應於一彩色彩色 濾光層單元與一感光區域12。隨後進行烘烤製程，將光阻 區塊32熔融後再固化，才形成如第3圖所示之半圓球形的 微透鏡結構36之陣列，而每個微透鏡結構36間所有之間 距40係與感光元件14約略相等。 然而，配合解析度(res〇luti〇n)提升、畫素尺寸以及感光 兀件14、線路的縮小化，對微透鏡結構36也產生了零間 距(^ero_gap)的要求。但根據習知之微透鏡製作方法，微透 制、、構36之間距4〇過小，將會造成微透鏡結構％在烘烤 製程中發^兩兩重疊(㈣咖)並產生橋狀物(bridge)的現 t也就H習知之微透鏡製作方法係無法獲得符合現 有令間距要求之微透鏡結構36。 因此’熟f該項技藝者係提出許多解決方法，如第4圖 6 200846703 所示之美國專利申請公開號US 2003/0111700 A1所提供之200846703 IX. INSTRUCTIONS: v Technical Field of the Invention The present invention relates to a method of fabricating an image sensor microlens, and more particularly to a method of fabricating a microlens array of an image sensor. [Prior Art] With the continuous development and growth of digital cameras and electronic scanning products, the demand for sensing elements on the market φ continues to increase. Currently, the commonly used image sensing includes the charge | Charger (charge C0Upietj device, CCD sensor) and complementary CMOS image sensor (CIS) two major categories. Micro-lens are formed on the image sensors to control the direction in which the light travels, so that the incident light is incident on the optical sensing element such as a photodiode. In order to improve the sensitivity of the image sensor. In the prior art, the microlens uses a photosensitive photoresist as a material to form a smooth curved surface required for the microlens after a melting bake process. Please refer to Figures 1 to 3, the first! Figures to 3 are schematic views of a conventional method of fabricating a microlens array. Referring to the drawings, first, a semiconductor substrate 10 is provided in which a photosensitive region 12 and a photosensitive member 14, such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS) image sensor, are formed. A light-transmissive dielectric layer π 200846703 is formed on the semiconductor substrate 10; and a dielectric filter array 18 is formed on the dielectric layer 16, and each color filter layer unit of the color filter array 18 corresponds to each In a photosensitive region 12, a light transmissive flat layer 20 is formed on the color filter array 18. As shown in Fig. 1, a layer 10 of microlens material composed of a photoresist is then formed on the flat layer 20. Please refer to Figures 2 and 3. Next, the microlens material layer 30 is patterned by a conventional lithography process to form an array 34 having a plurality of photoresist bumps 32, and each of the photoresist bumps 32 corresponds to a color color filter layer, respectively. The unit and a photosensitive area 12. Subsequently, the baking process is performed, and the photoresist block 32 is melted and then solidified to form an array of semi-spherical microlens structures 36 as shown in FIG. 3, and each microlens structure 36 is 40 lines apart from each other. The photosensitive elements 14 are approximately equal. However, with the resolution (res), the pixel size, and the reduction of the photosensitive element 14 and the line, a zero-interval (^ero_gap) is also required for the microlens structure 36. However, according to the conventional microlens manufacturing method, the micro-transparent and the structure 36 are too small, which will cause the microlens structure to be overlapped in the baking process ((4) coffee) and generate a bridge (bridge) The microlens structure 36, which is known from the prior art, is incapable of obtaining a microlens structure 36 that meets the existing spacing requirements. Therefore, the skilled person has proposed a number of solutions, as provided in U.S. Patent Application Publication No. US 2003/0111700 A1, which is incorporated herein by reference.
V 一組相對應之棋盤式（checkerboard)光罩50、52來達到零間 距之要求。請參閱第5圖與第6圖，首先使用光罩5〇圖案 化一微透鏡材料層（圖未示），以形成第一組光阻凸塊， 隨即進行一第一次烘烤製程，以形成如第6圖所示之第一 組微透鏡結構62。請參閱第7圖與第8圖，接著使用光罩 52另一圖案化微透鏡材料層（圖未示），以形成第二組光 _ 阻凸塊64，隨後即進行一第二次烘烤製程，以形成如第8 圖所示之第二組微透鏡結構66,並完成微透鏡陣列之製作。 值得注意的是，由於晝素尺寸之縮小，棋盤式光罩5〇、 52分別為包含之精密且微小微透鏡圖案之高階(high grade) 光罩’除有增加成本之考量外，同時也增加在曝光、顯影 及钱刻等步驟失敗之可能性而影響良率。此外，即使利用 此種相對應之棋盤式光罩5〇、52製作微透鏡結構時，仍無 鲁 法完全避免第一組微透鏡結構62於第二次烘烤製程中受 到溫度的影響而與相鄰之第二組微透鏡結構66產生橋狀 物68。所以，亦有熟知該項技藝者分別利用三次的微透鏡 材料層塗佈、微影製裎、以及不同溫度的烘烤製程，以取 得零間距的微透鏡結構陣列，但該方法既複雜且仍無法完 全避免不同組的微透鏡結構受其他烘烤製程中溫度的影 ^ 響。因此如何能在簡化製程的同時仍提高微透鏡結構陣列 之製作成果，仍為一需要解決之難題。 200846703 【發明内容】 因此，本發明於此提供影像感测器微透鏡結構之製作方 法，用以於簡化製程的同時提高微透鏡結構陣列的製作結 果。 根據本發明之申請專利範圍，係提供一種影像感測器微 透鏡結構之製作方法，該方法首先提供一至少包含有一平 坦層之半導體基底。接下來進行一第一微影製程，於該平 坦層表面形成一第一組微透鏡凸塊；隨後進行一第一烘烤 製程，於該平坦層表面形成一第一組微透鏡結構。緊接著 係進行一第一表面處理，以固化(harden)該第一組微透鏡結 構之表面。第一表面處理之後，係進行一第二微影製程， 於該平坦層表面形成一第二組微透鏡凸塊;隨後進行一第 二烘烤製程，於該平坦層表面形成一第二組微透鏡結構。 根據本發明之申請專利範圍，另提供一種影像感測器微 透鏡結構之製作方法，該方法首先提供一至少包含有一平 坦層之半導體基底。隨後進行一第一微影製程，利用一第 一棋盤式光罩於該平坦層表面形成一第一組微透鏡凸塊， 隨即進行一第一烘烤製程，於該平坦層表面形成一第一組 微透鏡結構。接下來進行一表面處理，以固化(harden)該第 一組微透鏡結構之表面。之後進行一第二微影製程，位移 該第一棋盤式光罩一間距單元而於該平坦層表面形成一第 200846703 、 二組微透鏡凸塊。最後進行-第二供烤製帛，於該平坦層 •表面形成一第二組微透鏡結構。 曰 根據本發明所提供之利用影像感測器微透鏡結構之製 作方法，係藉由分組製作微透鏡結構以獲得零間距之=透 鏡陣列。此外，第一組微透鏡結構形成後，即進行—第一 表面處理，以固化該第一組微透鏡結構之表面，使得該等 • 微透鏡結構不會在後續第二組微透鏡之製作過程中受到影 響，而可避免第一組微透鏡結構與第二組微透鏡結構產= 橋狀物，並提高微透鏡結構輪廓之完整性。 【實施方式】 請參閱第9圖至第17圖，第9圖至第Π圖係為本發明 所提供之影像感測器微透鏡結構之製作方法之第一較佳實 施例。如第9圖所示，首先提供一半導體基底1〇〇，半導 春體基底100内形成有複數個影像感測器102，例如電荷耦 合裝置(CCD)或者互補式金氧半導體(CM〇s)影像感應器 等。另有一透光之介電層104形成於半導體基底1〇〇上； 而介電層104上則係形成有一彩色濾光陣列1〇6，彩色濾 光俥列106中之每一彩色濾光層單元皆分別對應於一影像 感測器102，此外尚有一透光之平坦層1〇8形成於彩色濾 一 光陣列上’平坦層108之厚度約為5〇〇〇埃（angstrom)。 而如第9圖所示，隨後係於平坦層1〇8上形成一由感光性 200846703 材料’例如光阻，所構成之-第-微透鏡材料層110。. 、，請參閱第9圖與第1()圖。接下來係湘—第―棋盤式 光罩112進仃一第一微影製程，圖案化第—微透鏡材料層 110而於平垣㉟108表面形成如第10圖所示之-第-組微 透鏡凸塊114。 請參閱第11圖。進行一第一烘烤製程’熔融第一組微 透鏡圖凸塊114’而於平坦層108表面形成一第一組微透 鏡結構116。待第一組微透鏡結構116形成後，隨即進行一 表面處理120 ’以固化(harden)第一組微透鏡結構116之表 面。而經過表面處理120之第一組微透鏡結構ιΐ6係具有 一固化之表面，因此可避免其餘後續製程中受到影響。 在本發明之較佳實施例中，表面處理12〇可包含有削光 阻(de-scum)處理、紫外光固化處理(uv curing)、漂白作丨❹他) 處理、或化學藥劑處理等等。舉例來說，紫外光處理係可 利用一紫外光光源照射第一組微透鏡116表面；而漂白處 理則係可利用一般步進機(stepper)對第一組微透鏡116表 面進行曝光，以完成漂白處理。而化學藥劑處理則係利用 >^曱基吨口各酮（]^_]^^11>4-2-?>^〇11(1〇1^，]^1仰)與兩綱 (acetone)等溶液對第一組微透鏡116表面進行處理，以固 化第一組組微透鏡116之表面。而其中削光阻處理，則是 200846703 幻用3氧電漿對第一組微透鏡116表面進行声 形成-第二=弟13圖。接下來係於平垣層108表面 程鏡材料層13G，隨後係進行—第二微影製 _形^!=盤式光罩132圖案化第二微 成如弟13圖所示之—第二組微透鏡凸塊134。 值仔注意的是，在本發明之較佳實施例中，第一棋盤式 光罩112鱼筮一祕加』、 ^ ^ ，、弟一棋盤式光罩132係為一相同之光罩··亦即 將弟=棋盤式光罩112位移—間距單位(piteh)，便可將其 用於第-微影製程中。換句話說，第—組微透鏡凸塊ιΐ4 與該二組微透鏡凸塊134係為相差—間距單位之二陣列圖 案。 请參閱第14圖。隨後進行一第二烘烤製程，熔融第二 組微透鏡凸塊134,而於平坦層⑽表面形成—第二組微 透鏡結構136,且獲得一零間距之微透鏡陣列14〇。此外， 由於第一組微透鏡結構116係已經過表面處理，而具有一 固化之表面，因此即使第二烘烤製程之溫度與第一烘烤製 耘之溫度相同，也不會影響第一組微透鏡結構116之表面 輪廊。 請參閱第15圖與第16圖。由於第_組微透鏡結構n6 200846703 、 與第一組微透鏡結構136係具有相同高度，因此可能使得 微透鏡結構陣列140產生如鏡面之效果，提高光線的反射 度(reflectlvity)而減少入射光。為避免上述問題，除可利用 不同厚度之第一微透鏡材料層110與第二微透鏡材料層 130之外’亦可於進行表面處理12()中的削光阻處理時， 藉由調整製程時間等參數，而於固化第一組微透鏡116表 面的同時领刻平坦層1〇8，而於第一組微透鏡結構116之 # 間形成如第15圖所示之凹槽150，凹槽150之一深度係為 200〜1〇〇〇埃。隨後始進行第二組微透鏡結構之製作，於 凹槽150内形成第二組微透鏡結構，由於該等步驟與前述 步驟相同，因此於此不再贅述。如第16圖所示，藉由於削 光阻處理中所產生之凹槽15〇深度，可調整第一組微透鏡 結構116與苐一組微透鏡結構13 6之高度差，獲得一不平 坦的表面，因此降低了入射光線的反射度，相對地提高了 I 影像感測器102的感光度。 綜上所述，本第-較佳實施例所提供之影像感測器微透 鏡結構之製作方法，係利用同一棋盤式光罩之位移製作一 微透鏡陣列，而該微透鏡陣列則包含有兩組具相對應圖案 且零間距之微透鏡結構。與習知技術中需兩個具相對應圖 案之光罩來形成微透鏡結構之方法相較，係可省卻一^ 罩。由於微透鏡圖案光罩係為一精密且具微小微透鏡圖案 .之高階光罩’因此本較佳實施例所提供方法係可有效降低 12 200846703 成本。此外，本佳實施例所提供之方法係於形成第一&微 透鏡結構⑽後立即進行-表面處理，㈣化第—組微透 鏡結構Π6之表面，使得第一組微透鏡結構116不會在後 續第二組微透鏡結構136之製作過程中受到影響，二可避 免第一組微透鏡結構116與第二組微透鏡結構136之間產 生橋狀物，並提咼微透鏡結構表面輪廓之完整性。簡單地 說，本第，較佳實施例所提供之方法，係可藉由位移一相 同之棋盤式光罩與進行一表面處·理之方法，於簡化製程及 降低成本的同時，達到微透鏡結構零間距之要求，並提升 微透鏡結構表面輪廓之完整性。 此外，因應影像感測器對紅色、綠色、以及藍色不同波 長光線的感光度要求，本發明所提供之影像感測器微透鏡 結構之製作方法，亦可針對R/G/B三種影像感測器分組製 作具相同或不同尚度之微透鏡結構。請參閱第17圖至第 19圖，第Π圖至第19圖係為本發明所提供之影像感測器 微透鏡結構之製作方法之第二較佳實施例。如第17圖所 示’首先提供一半導體基底200，半導體基底200内形成 有複數個影像感測器202R、202G、202B，例如電荷耦合 裝置(CCD)或者互補式金氧半導體(CMOS)影像感應器等。 另有一透光之介電層204形成於半導體基底200上；而介 私層204上則係形成有一彩色濾光陣列，彩色濾光陣列中 之彩色濾光單元2〇6R、206G、206B係分別對應於影像感 13 200846703 、 、 測裔如汉、202G、202B，此外尚有一透光之平坦層208 形成於彩色濾光陣列206上，爭坦層208之厚度約為50〇〇 埃（angstrom)。 請繼續參閱第17圖。接下來係進行一第一微影製程， 利用第棋盤式光罩（圖未示）於平坦層208表面形成 一第一組微透鏡凸塊（圖未示）；隨後進行一第一烘烤製 =，於平坦層表面2G8形成—對應於彩色濾光單元證之 弟二組微透鏡結構21GR。由於微透鏡結構之製程係同於上 =;微透鏡結構或第二組微透鏡結構之製程，故於此 係不再i述。同理，以卞-第二組微透鏡結構21犯血 三組微透鏡結構21GB之製程亦予以省略。待第一組微透於 結構210R形成後，隨即進行一一 v 、見 第一經微透鏡結構210R之表面。、处理220 ’以固化 請參閱第18圖。隨後係進行 第二棋盤式弟一斂衫製耘，利用— 、皿式先罩（圖未不）於平垣層2 _ 透鏡凸塊（圖未示），並進行— / —組微 208表面形成一對應於彩色濾_、烤衣私於平坦層 結構⑽。同樣地，在形成第二二娜之第二組微透萄 隨即進行-第二表面處理222，透鏡結構2l〇G後， 210G之表面。 *化第二組微透鏡結構 14 200846703 請參閱第19圖。最後係進行一第三微影製程，利用— 第三棋盤式光罩（圖未示）於平坦層2〇8形成一第三組微 透鏡凸塊（圖未示），並進行一第二烘烤製程，於平坦層 208表面形成一對應於彩色濾光單元2〇6B2第三組微透鏡 結構210B ’並完成微透鏡陣列2〗〇之製作。 第一表面處理220與第二表面組裡222係包含有削光阻 ❿ （de_scum)處理、紫外光固化處理(UV curing)、漂白（bleach) 處理、或化學藥劑處理等等。如前所述，紫外光處理係可 利用一紫外光光源照射第一組微透鏡結構21〇R與第二組 微透鏡結構210G表面；而漂白處理則係可利用一般步進機 (stepper)對第一組微透鏡結構21〇R與第二組微透鏡結構 210G表面進行曝光，以完成漂白處理。而化學藥劑處理則 包含有N-曱基吡咯酮(N_Methyl_2-Pyrr〇lid_，NMp)與丙 酮(aCet〇ne)等溶液。削光阻處理，則是利用一含氧電漿對 第一組微透鏡結構210R與第二組微透鏡結構21〇Q表面進 行處理。 同理，進<了削光阻處理時，係可藉由輕製程時間等參 數，而於固化第組微透鏡結構2魔或第二組微透鏡結構 210G表面的同時餘刻平坦層扇，而於平坦層内形成複數 個凹槽（圖未示），而凹槽之-深度係為2〇〇〜1〇〇〇埃。該 等凹槽係可用以調整第二組微透鏡結構21〇〇或第三組微 15 200846703 透鏡結構210B之高度，使微透鏡陣列21〇具有—不平扫表 面’而可降低反射率’相對地提升感光纟。而後始進行後 續微透鏡結構之製作。此外，本第二較佳實施例所提供之 第一組微透鏡結構210R、第二組微透鏡結構21〇(}、與第 三組微透鏡結構210B之高度、大小以及製作順序係不受本 說明書與圖示所限。 根據本發明所&供之弟二較佳實施例，由於製作第一組 微透鏡結構210R與製作第二組微透鏡結構21〇G之間係進 行弟一表面處理220以固化第一組微透鏡結構21 之表 面；而製作第二組微透鏡結構210G與製作第三組微透鏡結 構210B之間係進行一第二表面處理222以固化第二組微透 鏡結構210G之表面，因此各組微透鏡結構將不會受到其他 組微透鏡製程之影響，而於後續製程中產生橋狀物，故可 確保各組微透鏡結構之輪廊完整性。此外’亦可藉由削光 阻處理，於平坦層208上形成凹槽，用以調整微透鏡結構 之高度，不僅可降低光線的反射度，更可根據影像感測器 2〇2針對不同波長光線之感光度要求，調整削光阻處理之 製程參數以及凹槽深度，製作符合產品規格要求之微透鏡 結構21 〇。 综上所述’本發明所提供之利用影像感測器微透鏡結構 之製作方法，係藉由分組製作微透鏡結構獲得零間距之微 16 200846703 、 透鏡陣列。此外，前組微透鏡結構形成後，即進行一表面 處理以固化該組組微透鏡結構之表面，使得該等微透鏡 、、、口構不會在後續微透鏡結構之製作過程中受到影響，而可 避免兩組微透鏡結構之間產生橋狀物 ，更確保了各組微透 鏡結構輪廓之完整度。 以上所述僅為本發明之較佳實施例，凡依本發明申請專 Φ 利範圍所做之均等變化與修飾，皆應屬本發明之涵蓋範圍。 【圖式簡單說明】 =1圖至第3圖乃一習知之微透鏡陣列製作方法之示意圖。 第4圖所不係美國專利申請公開號US 2003/0111700 A1所 提供之一組相對應之棋盤式（checkerboard)光罩。 ，5圖至第8圖係為另一習知之微透鏡製作方法之示意圖。 第9圖至第16圖係為本發明所提供之影像感測器微透鏡結 構之製作方法之第一較佳實施例。 第17圖至帛I9目係為本發明所提供之影像感測器微透鏡 結構之製作方法之第二較佳實施例。 【主要元件符號說明】 10 半導體基底 12 14 感光元件 16 18 彩色濾光陣列 20 感光區域 介電層 平坦層 17 200846703V A set of corresponding checkerboard masks 50, 52 to achieve zero spacing requirements. Referring to FIG. 5 and FIG. 6 , a microlens material layer (not shown) is first patterned using a mask 5 , to form a first set of photoresist bumps, and then a first baking process is performed to A first set of microlens structures 62 as shown in Fig. 6 is formed. Referring to Figures 7 and 8, then another patterned microlens material layer (not shown) is used to form a second set of light-resistance bumps 64, followed by a second bake. The process is performed to form a second set of microlens structures 66 as shown in FIG. 8 and the fabrication of the microlens array is completed. It is worth noting that due to the reduction in the size of the halogen, the checkerboard masks 5〇, 52 are respectively high-grade masks containing precise and tiny microlens patterns, in addition to the increase in cost considerations, The possibility of failure in steps such as exposure, development, and money engraving affects yield. In addition, even when the microlens structure is fabricated by using the corresponding checkerboard masks 5, 52, there is no law to completely prevent the first group of microlens structures 62 from being affected by temperature during the second baking process. The adjacent second set of microlens structures 66 create a bridge 68. Therefore, it is also known that the skilled person uses three times of microlens material layer coating, lithography, and different temperature baking processes to obtain a zero-pitch microlens structure array, but the method is complicated and still It is not possible to completely avoid the effects of different sets of microlens structures on temperatures in other baking processes. Therefore, how to improve the manufacturing process of the microlens structure array while simplifying the process is still a difficult problem to be solved. SUMMARY OF THE INVENTION Accordingly, the present invention provides a method of fabricating an image sensor microlens structure for simplifying the process while improving the fabrication results of the microlens structure array. According to the scope of the invention, there is provided a method of fabricating an image sensor microlens structure, which first provides a semiconductor substrate comprising at least one planar layer. Next, a first lithography process is performed to form a first set of microlens bumps on the surface of the flat layer; then a first baking process is performed to form a first set of microlens structures on the surface of the flat layer. A first surface treatment is then performed to harden the surface of the first set of microlens structures. After the first surface treatment, a second lithography process is performed to form a second set of microlens bumps on the surface of the flat layer; then a second baking process is performed to form a second set of micro-surfaces on the surface of the flat layer. Lens structure. According to the scope of the invention, there is further provided a method of fabricating an image sensor microlens structure, which first provides a semiconductor substrate comprising at least one planar layer. Then performing a first lithography process, forming a first set of microlens bumps on the surface of the flat layer by using a first checkerboard mask, and then performing a first baking process to form a first surface on the surface of the flat layer Group microlens structure. A surface treatment is then performed to harden the surface of the first set of microlens structures. Then, a second lithography process is performed, the first checkerboard mask is spaced apart from the pitch unit, and a second layer of the second lens lenticular bumps is formed on the surface of the flat layer. Finally, a second baking process is performed to form a second set of microlens structures on the surface of the flat layer. According to the method of fabricating the image sensor microlens structure provided by the present invention, the microlens structure is fabricated by grouping to obtain a zero-pitch = lens array. In addition, after the first group of microlens structures are formed, a first surface treatment is performed to cure the surface of the first group of microlens structures, such that the microlens structures are not fabricated in the subsequent second group of microlenses. The effect is avoided, and the first set of microlens structures and the second set of microlens structures can be avoided to produce a bridge and improve the integrity of the microlens structure profile. [Embodiment] Please refer to Fig. 9 to Fig. 17, and Fig. 9 to Fig. 9 are first preferred embodiments of the method for fabricating the image sensor microlens structure provided by the present invention. As shown in FIG. 9, a semiconductor substrate 1 is first provided, and a plurality of image sensors 102 are formed in the semiconductor body substrate 100, such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CM〇s). ) Image sensors, etc. Another light-transmissive dielectric layer 104 is formed on the semiconductor substrate 1; and the dielectric layer 104 is formed with a color filter array 1〇6, each of the color filter arrays 106. The units respectively correspond to an image sensor 102, and a light transmissive flat layer 1〇8 is formed on the color filter array. The thickness of the flat layer 108 is about 5 angstroms. As shown in Fig. 9, a layer of the first-microlens material 110 is formed on the flat layer 1 to 8 by a photosensitive material 200846703 material such as a photoresist. . Please refer to Figure 9 and Figure 1(). Next, the first-the first lithography process is performed, and the first lithography process is patterned, the first microlens material layer 110 is patterned, and the first-group microlens convex is formed on the surface of the flat surface 35108 as shown in FIG. Block 114. Please refer to Figure 11. A first baking process 'melting the first set of microlens pattern bumps 114' is performed to form a first set of microlens structures 116 on the surface of the planar layer 108. After the first set of microlens structures 116 are formed, a surface treatment 120' is performed to harden the surface of the first set of microlens structures 116. The first set of microlens structures ι 6 having undergone surface treatment 120 have a cured surface, thereby avoiding the effects of the remaining subsequent processes. In a preferred embodiment of the invention, the surface treatment 12 can include de-scum treatment, uv curing, bleaching treatment, or chemical treatment, and the like. . For example, the ultraviolet light treatment can use an ultraviolet light source to illuminate the surface of the first group of microlenses 116; and the bleaching process can expose the surface of the first group of microlenses 116 by using a general stepper to complete Bleaching treatment. The chemical treatment is based on the use of > 曱 曱 吨 口 各 each ketone (] ^ _] ^ ^ 11 > 4-2-? > 〇 ( 11 (1 〇 1 ^, ^ ^ 1 Yang) and two A solution such as acetone) treats the surface of the first set of microlenses 116 to cure the surface of the first set of microlenses 116. And wherein the photo-resistance treatment is 200846703, the 3D plasma is applied to the first set of microlenses 116. The surface is acoustically formed - the second = the same as the 13th image. The next layer is the surface mirror material layer 13G of the flat layer 108, and then the second lithography _ shape ^! = the disk reticle 132 is patterned the second micro The second set of microlens bumps 134 are shown in Fig. 13 as a figure. It is noted that in the preferred embodiment of the invention, the first checkerboard mask 112 is a squid, ^ ^ , the brother of a checkerboard reticle 132 is a same reticle · · also the younger = checkerboard reticle 112 displacement - pitch unit (piteh), which can be used in the first lithography process. In other words, the first group of microlens bumps ι4 and the two sets of microlens bumps 134 are two array patterns of phase difference-pitch units. Please refer to Fig. 14. Then a second baking process is performed to melt the second Microlens bumps 134, and a second set of microlens structures 136 are formed on the surface of the planar layer (10), and a zero pitch microlens array 14A is obtained. Furthermore, since the first set of microlens structures 116 have been surface treated, There is a cured surface, so that even if the temperature of the second baking process is the same as the temperature of the first baking process, the surface gallery of the first group of microlens structures 116 is not affected. See Figure 15 and Figure 16. Since the first group of microlens structures n6 200846703 have the same height as the first group of microlens structures 136, it is possible to cause the microlens structure array 140 to have a mirror effect, thereby improving the reflectivity of the light and reducing it. In order to avoid the above problem, in addition to the use of the first microlens material layer 110 and the second microlens material layer 130 of different thicknesses, it is also possible to perform the photo-resistance processing in the surface treatment 12(). By adjusting the process time and the like, the flat layer 1〇8 is engraved while curing the surface of the first group of microlenses 116, and the groove 150 as shown in FIG. 15 is formed between # of the first group of microlens structures 116. , One of the grooves 150 has a depth of 200 to 1 angstrom. Then, the second group of microlens structures are fabricated, and a second group of microlens structures are formed in the grooves 150. Since the steps are the same as the foregoing steps, Therefore, as shown in FIG. 16, the height difference between the first group of microlens structures 116 and the first group of microlens structures 13 can be adjusted by the depth of the grooves 15 产生 generated in the photoresist process. An uneven surface is obtained, thereby reducing the reflectance of the incident light, and the sensitivity of the I image sensor 102 is relatively increased. In summary, the image sensor microlens structure provided by the first preferred embodiment is formed by using the displacement of the same checkerboard mask to form a microlens array, and the microlens array includes two A microlens structure having a corresponding pattern and zero pitch is assembled. Compared with the conventional method in which two masks having corresponding patterns are required to form a microlens structure, a mask can be omitted. Since the microlens pattern mask is a high precision mask with a fine microlens pattern, the method provided by the preferred embodiment can effectively reduce the cost of 12 200846703. In addition, the method provided by the preferred embodiment is to perform surface treatment immediately after forming the first & microlens structure (10), and (4) to planarize the surface of the first group of microlens structures ,6 so that the first group of microlens structures 116 are not In the subsequent fabrication process of the second set of microlens structures 136, the bridge between the first set of microlens structures 116 and the second set of microlens structures 136 can be avoided, and the surface profile of the microlens structure can be improved. Integrity. Briefly, the method provided by the preferred embodiment of the present invention can achieve the microlens while simplifying the process and reducing the cost by shifting the same checkerboard mask and performing a surface treatment method. The requirement of zero spacing of the structure and the integrity of the surface profile of the microlens structure. In addition, in response to the sensitivity requirements of the image sensor for red, green, and blue different wavelengths of light, the image sensor microlens structure provided by the present invention can also be used for R/G/B three image senses. The detectors are grouped to produce microlens structures of the same or different degrees. Referring to FIG. 17 to FIG. 19, FIG. 19 to FIG. 19 are second preferred embodiments of the method for fabricating the image sensor microlens structure provided by the present invention. As shown in FIG. 17, a semiconductor substrate 200 is first provided, and a plurality of image sensors 202R, 202G, 202B, such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS) image sensing, are formed in the semiconductor substrate 200. And so on. Another light transmissive dielectric layer 204 is formed on the semiconductor substrate 200; and the color filter layer 204 is formed with a color filter array. The color filter units 2〇6R, 206G, and 206B in the color filter array are respectively Corresponding to the image sense 13 200846703, , the image of the Han, 202G, 202B, in addition, there is a light-transmissive flat layer 208 formed on the color filter array 206, the thickness of the layer 208 is about 50 angstroms (angstrom) . Please continue to see Figure 17. Next, a first lithography process is performed, and a first set of microlens bumps (not shown) is formed on the surface of the flat layer 208 by using a checkerboard mask (not shown); then a first baking system is performed. =, formed on the surface of the flat layer 2G8 - corresponding to the two sets of microlens structures 21GR of the color filter unit. Since the process of the microlens structure is the same as that of the upper =; microlens structure or the second group of microlens structures, it will not be described here. Similarly, the process of smashing the blood of the three groups of microlens structures 21 by the second group of microlens structures 21 is also omitted. After the first set of micro-transparent structures 210R are formed, the surface of the first trans-microlens structure 210R is seen. , handle 220 ’ for curing. See Figure 18. Subsequently, the second checkerboard type is used to make the shirt, using the -, the first cover of the dish (not shown) in the flat layer 2 _ lens bump (not shown), and the surface formation of the micro-208 One corresponds to the color filter _, and the baking ware is private to the flat layer structure (10). Similarly, the second set of micro-transmissions in the formation of the second dinas is performed immediately - the second surface treatment 222, the lens structure 2l 〇 G, the surface of 210G. * The second set of microlens structures 14 200846703 See Figure 19. Finally, a third lithography process is performed, and a third set of microlens bumps (not shown) is formed on the flat layer 2〇8 by using a third checkerboard mask (not shown), and a second baking is performed. The baking process forms a third group of microlens structures 210B' corresponding to the color filter unit 2〇6B2 on the surface of the flat layer 208 and completes the fabrication of the microlens array 2. The first surface treatment 220 and the second surface group 222 include a de-scum treatment, a UV curing treatment, a bleach treatment, a chemical treatment, and the like. As described above, the ultraviolet light treatment can illuminate the first group of microlens structures 21〇R and the second group of microlens structures 210G with an ultraviolet light source; and the bleaching process can utilize a general stepper pair. The first set of microlens structures 21A and R are exposed to the surface of the second set of microlens structures 210G to complete the bleaching process. The chemical treatment includes a solution of N-mercaptopyrrolidone (N_Methyl_2-Pyrr〇lid_, NMp) and acetone (aCet〇ne). The photoresisting process is performed by treating the first group of microlens structures 210R and the second group of microlens structures 21〇Q with an oxygen-containing plasma. Similarly, when the photoresist processing is performed, the flat layer fan can be cured while curing the surface of the first group of microlens structure 2 or the second group of microlens structures 210G by parameters such as light process time. A plurality of grooves (not shown) are formed in the flat layer, and the groove-depth is 2 〇〇 1 〇〇〇 。. The grooves can be used to adjust the height of the second set of microlens structures 21 〇〇 or the third set of micro 15 200846703 lens structures 210B such that the microlens array 21 〇 has an - uneven surface 'to reduce the reflectivity' relatively Improve photosensitivity. Then, the fabrication of the microlens structure is continued. In addition, the height, size, and manufacturing order of the first group of microlens structures 210R, the second group of microlens structures 21〇, and the third group of microlens structures 210B provided by the second preferred embodiment are not The specification and the illustration are limited. According to the preferred embodiment of the present invention, since the first group of microlens structures 210R and the second group of microlens structures 21〇G are fabricated, a surface treatment is performed. 220 to cure the surface of the first set of microlens structures 21; and between the second set of microlens structures 210G and the third set of microlens structures 210B to perform a second surface treatment 222 to cure the second set of microlens structures 210G The surface of each group, so the microlens structure of each group will not be affected by other groups of microlens processes, and bridges will be produced in subsequent processes, thus ensuring the integrity of the corridors of each group of microlens structures. By the photoresist processing, a groove is formed on the flat layer 208 for adjusting the height of the microlens structure, which not only reduces the reflectance of the light, but also depends on the sensitivity of the image sensor 2〇2 for different wavelengths of light. Adjusting the process parameters of the photoresist processing and the groove depth to produce a microlens structure 21 符合 that meets the product specifications. In summary, the method for manufacturing the microlens structure using the image sensor provided by the present invention is A micro-lens structure is formed by grouping to obtain a micro-pitch of the micro-lens 16 200846703, a lens array. Further, after the front set of micro-lens structures are formed, a surface treatment is performed to cure the surface of the set of micro-lens structures, such that the micro-lenses, The mouth structure is not affected during the fabrication of the subsequent microlens structure, and the bridge between the two groups of microlens structures can be avoided, and the integrity of the contours of each group of microlenses is ensured. For the preferred embodiments of the present invention, the equivalent changes and modifications made by the application of the present invention should be within the scope of the present invention. [Simplified Schematic] =1 to 3 A schematic diagram of a method for fabricating a microlens array. Figure 4 is not a set of corresponding checkerboards provided by U.S. Patent Application Publication No. US 2003/0111700 A1. 5.2. Fig. 8 is a schematic view of another conventional microlens manufacturing method. Fig. 9 to Fig. 16 are the first comparison methods for manufacturing the image sensor microlens structure provided by the present invention. The first embodiment is a second preferred embodiment of the method for fabricating the image sensor microlens structure provided by the present invention. [Main element symbol description] 10 semiconductor substrate 12 14 photosensitive element 16 18 color filter array 20 photosensitive area dielectric layer flat layer 17 200846703
30 微透鏡材料層 32 光阻凸塊 34 陣列 36 微透鏡結構 40 間距 50、52 棋盤式光罩 60 第一組光阻凸塊 62 第一組微透鏡結構 64 第二組光阻凸塊 66 第二組微透鏡結構 68 橋狀物 100 半導體基底 102 影像感測器 104 介電層 106 彩色濾光陣列 108 平坦層 110 第一微透鏡材料層 112 第一棋盤式光罩 114 第一組微透鏡凸塊 116 第一組微透鏡結構 120 表面處理 130 第二微透鏡材料層 132 第二棋盤式光罩 134 第二組微透鏡凸塊 136 第二組微透鏡結構 140 微透鏡陣列 150 凹槽 200 半導體基底 202R、 202G、202B 影像感測器 204 介電層 206 彩色濾光陣列 206R、 206G、206B 彩色濾光單元 208 平坦層 210 微透鏡陣列 210R 第一組微透鏡結構 210G 第二組微透鏡結構 210B 第三組微透鏡結構 220 第一表面處理 222 第二表面處理 1830 microlens material layer 32 photoresist bump 34 array 36 microlens structure 40 pitch 50, 52 checkerboard mask 60 first set of photoresist bumps 62 first set of microlens structures 64 second set of photoresist bumps 66 Two sets of microlens structures 68 Bridges 100 Semiconductor substrate 102 Image sensor 104 Dielectric layer 106 Color filter array 108 Flat layer 110 First microlens material layer 112 First checkerboard mask 114 First set of microlens bumps Block 116 first set of microlens structures 120 surface treatment 130 second microlens material layer 132 second checkerboard 134 second set of microlens bumps 136 second set of microlens structures 140 microlens array 150 grooves 200 semiconductor substrates 202R, 202G, 202B image sensor 204 dielectric layer 206 color filter array 206R, 206G, 206B color filter unit 208 flat layer 210 microlens array 210R first group of microlens structure 210G second group of microlens structure 210B Three sets of microlens structures 220 First surface treatment 222 Second surface treatment 18