M432133 五、新型說明： 【新型所屬之技術領域】 本新型是有關於一種光罩’特別是指一種針對不同的 半導體設計圖形尺寸或半導體設計圖形密集度（Pattern loading)之具有不同遮光層厚度，以提升微影製程空間的光 罩。 【先前技術】 隨著電子產品電路元件的密集度不斷提高，半導體微 春影成像技術也不斷地隨之演進，以符合製作出更微細化影 像的需求。擴大焦距深度（Depth of focus，DOF)以增加微影 製程空間（Process window)有助減少產品的重工率與良率損 失，而改善解析度也是微影技術中重要的課題。提昇解析 度的方式有許多種，例如：使用較大數值孔徑（Numerical aperture)的透鏡、或使用更短波長的曝光光源從過去的工_ line(波長=365奈米），轉換到現今已廣泛使用的深紫外光 KrF(波長=248奈米），及ArF(波長=193奈米），另外，相位 ♦ 移光罩、偏軸式照射（0ff_axis illuminati〇n)等技術也可增強 解析能力。 - 一般，在半導體元件的製作過程中，需要分別利用多 道的光罩製程使晶圓上之光阻圖案化，並成為例如：姓刻 或離子植入步驟前之遮罩。參閱圖丄、圖2,圖“頁示一種 目前用於形成不同線路密度的二元式光罩1及經該光罩i +光後在B曰圓1 〇〇上形成的光阻線路圖案i 02，圖2則是 -微影曝光系統200及與該光罩"目對位置示意圖。該光 3 M432133 罩1的結構包含一片基板11及一預設圖案12，該預設圖案 12具有多數個彼此交錯設置且厚度實質相同的金屬遮光層 121及多數個由相鄰兩遮光層121共同界定出之透光區1.22 。當在該光罩1上設計並製作出該預設圖案12後，利用如 圖2所示的微影曝光系統200，將該光罩1置放於該微影曝 光系統200令’並經一曝光光源201照射，便可將該預設 圖案12轉移至晶圓1〇〇上的光阻層ι〇1，之後再將曝光後 的光阻層101經過曝光後烘烤（Post exp〇sure bake，以下簡 稱PEB)、顯影等後續步驟即可將該晶圓1〇〇上的光阻層 1〇1成型出特定之光阻圖案102,該光阻圖案102具有與該 光罩1之遮光層121形狀相似的線路i〇3(Line)及對應該透 光區122的間隙i〇4(Space)。 其中，該光罩1上的預設圖案12經曝光光源照射後會 在透鏡之相反側的一聚焦平面（F〇cal plane)成像，當該聚焦 平面與一最佳的光阻平面重疊時，經過後硬化及顯影步驟 後會得到解析度最佳的光阻圖案1〇2。然而，由於聚焦透鏡 的品質不佳或是曝光光源通過該些透光區122而照射至該 光阻層101時，會因為該些透光區122密度不同、或是經 曝光後的光阻於PEB等後續製程時，會因為氫離子擴散程 度的差異令該光阻層101在同一聚焦平面產生不同濃度的 光酸，使得在不同線路密度區域形成的光阻圖案會有光阻 行為表現不一致的解析度問題；或是因&光線在通過該些 透光區122時，於鄰近該些遮光層121邊緣產生的繞射現 象，使得該些透光區122與該遮光層121之間的光強度對 4 M432133M432133 V. New description: [New technical field] The present invention relates to a reticle, in particular to a different opaque layer thickness for different semiconductor design pattern sizes or semiconductor design pattern loading. A reticle that enhances the lithography process space. [Prior Art] As the density of circuit components of electronic products continues to increase, semiconductor micro-spring imaging technology has also evolved to meet the demand for making more detailed images. Increasing the depth of focus (DOF) to increase the lithography process window helps reduce the rework rate and yield loss of the product, and improving the resolution is also an important issue in lithography. There are many ways to increase the resolution, such as using a lens with a larger numerical aperture or using a shorter wavelength exposure source from the past work line (wavelength = 365 nm), which has been widely used today. The deep ultraviolet KrF (wavelength = 248 nm) and ArF (wavelength = 193 nm) are used. In addition, the phase ♦ shifting mask and off-axis illumination (0ff_axis illuminati〇n) can also enhance the resolution. - Generally, in the fabrication of semiconductor components, it is necessary to separately pattern the photoresist on the wafer by using a plurality of mask processes, and to become, for example, a mask before the surname or ion implantation step. Referring to FIG. 2 and FIG. 2, a page shows a binary mask 1 which is currently used to form different line densities, and a photoresist pattern i formed on the B circle 1 经 after passing through the mask i + light. 02, FIG. 2 is a schematic diagram of the lithography exposure system 200 and the reticle. The structure of the illuminating 3 M432133 cover 1 comprises a substrate 11 and a predetermined pattern 12, the preset pattern 12 having a majority a metal light-shielding layer 121 which is alternately disposed and substantially the same in thickness, and a plurality of light-transmissive regions 1.22 defined by two adjacent light-shielding layers 121. When the predetermined pattern 12 is designed and fabricated on the mask 1, the use As shown in the lithography exposure system 200 of FIG. 2, the reticle 1 is placed in the lithography exposure system 200 and irradiated by an exposure light source 201, and the preset pattern 12 can be transferred to the wafer 1 The photoresist layer 〇1 on the enamel, and then the exposed photoresist layer 101 is subjected to post-exposure bake (PB), development and other subsequent steps to the wafer. The photoresist layer 1 〇 1 is formed with a specific photoresist pattern 102 , and the photoresist pattern 102 has the reticle 1 The light shielding layer 121 has a similar shape line i〇3 (Line) and a gap i〇4 (Space) corresponding to the light transmitting area 122. The predetermined pattern 12 on the mask 1 is irradiated by the exposure light source and is then in the lens. A plane of focus on the opposite side is imaged. When the plane of focus overlaps with an optimum plane of photoresist, a post-hardening and developing step results in a photoresist pattern 1〇2 having the best resolution. However, because the quality of the focusing lens is not good or the exposure light source is irradiated to the photoresist layer 101 through the light transmitting regions 122, the density of the light transmitting regions 122 may be different or the exposed photoresist may be In the subsequent processes such as PEB, the photoresist layer 101 generates different concentrations of photoacids in the same focal plane due to the difference in the degree of diffusion of hydrogen ions, so that the photoresist patterns formed in different line density regions may have inconsistent photoresistive behavior. a resolution problem; or a diffraction phenomenon between the light-transmitting regions 122 and the light-shielding layer 121 due to the diffraction phenomenon generated by the light rays passing through the light-transmitting regions 122 adjacent to the light-shielding layers 121 Strength to 4 M432133
比降低’造成顯影後圖案失真；或是因為該晶圓表面凹凸 不平使仔形成於該晶圓上的光阻厚度不均句，而曝光後因 為通過該光罩的曝光光源會聚焦在該光阻的同一水平.面上 /因此，對不同厚度的光阻I⑻而言，也容易造成顯影 後开v成之S阻圖案表現不_致的解析度問題或是局部圖 案在對準時會產生聚焦深度變化或失焦（Def。⑽而產生線 寬變異超過規格範圍、邊緣粗糙度變差，或光阻截面輪廓 變差的問題’而導致例如，如圖3A所示在高線路密度區域 形成之線路1〇3有頂部面積過小、高度不足或是如圖3b 、所示在線路1〇3的末端有圓弧化⑽仙土㈣的現象、 或是末端產生足部(F〇〇ting pr〇fUe)’或是因為形成之間隙 1 〇4的關鍵尺寸誤差導致該間隙〗Q4產生頸縮⑽咖㈣等顯 影圖案失真問題。 傳統在解決失焦所造成的顯影後圖案失真的努力上， 有的針對微影設備改良，有的將曝光過程可能造成失焦的Ratio reduction causes pattern distortion after development; or because the surface of the wafer is uneven, the thickness of the photoresist formed on the wafer is uneven, and after exposure, the light is focused on the light source through the mask The same level of resistance. On the surface / therefore, for different thicknesses of photoresist I (8), it is also easy to cause the resolution of the S-resist pattern after development to be unresolved or the local pattern will produce focus when aligned. Depth variation or out-of-focus (Def. (10) causes a line width variation exceeding a specification range, edge roughness is deteriorated, or a problem that a cross-sectional profile of a photoresist is deteriorated'), for example, is formed in a high line density region as shown in FIG. 3A. Line 1〇3 has a small top area, insufficient height, or a circular arc (10) parietal (four) at the end of line 1〇3 as shown in Fig. 3b, or a foot end (F〇〇ting pr〇) fUe)' or because of the critical dimension error of the gap 1 〇4 formed, the gap Q8 produces a problem of distortion of the developing pattern such as necking (10) coffee (four). Traditionally, in the efforts to solve the pattern distortion after development caused by out of focus, For lithography Equipment improvement, and some may cause defocusing during the exposure process
因子建構出即時偵測並回饋修正的系統，另外，目前在半 導體製程中’當確；t進行微影曝光前，會先挑選產品晶圓 進行對f、曝光矩㈣⑽Exp〇sure Matdx)的量測來決定最佳 的製程焦距值。然巾，已揭露的眾多方法中，對於在同一 晶片上因線路密度差異或是結構之平坦度不均等問題造成 的顯影解析度不佳或是微區域失焦等問題仍然沒有較 改善方式。 【新型内容】 因此 1本新型之目的，即在提供— 種針對不同的半導 5 體°又6十圖形尺寸或半導體設計圖形密集度（Pattern loading) 設計，而可提升微影製程空間的光罩。 此外，本新型之另一目的，即，在提供一種用以改善光 阻層於曝光顯影後形成之光阻圖案變形失真問題的光罩。 於疋，本新型之光罩用以形成與一半導體元件線路相 對應的光阻圖案，包含一透光基板、複數個遮光圖案，及 複數個透光區。 該透光基板允許一曝光光源通過，該些遮光圖案間隔 設置於該透光基板表面，可阻隔該曝光光源而令穿透過該 等遮光圖案之光的能量低於一光阻的感光能量，該些透光 區疋由該些遮光圖案界定出，允許該曝光光源通過而令該 光阻感光該些遮光圖案共同構成預計形成之該光阻圖案 ’並具有至少兩種厚度。 此外’本新型之光罩包含一透光基板、一個遮光單元 ，及複數個透光區。 該透光基板允許一曝光光源通過，該遮光單元設置於 該透光基板表面，可阻隔該曝光光源而令穿透過該遮光單 元之光的能量低於一光阻的感光能量，該些透光區由該遮 光單元界定出並允許該曝光光源通過而令該光阻感光其 中’該遮光單元具有多個彼此間隔排列的遮光圖案且該 每一個遮光圖案具有至少兩種不同的厚度。 本新型之功效在於：利用具有至少兩種厚度之遮光圖 案的光罩’令曝光光源於通過該光罩的透光區時產生不同 的光學現象並在該光阻層形成不同深度的聚焦平面，用以 M432133 改善該光阻層於曝光顯影後形成之光阻圖案變形失真的問 題，而可擴大微影製程空間。 【實施方式】 有關本新型之前述及其他技術内容、特點與功效，在 乂下配&參考圖式之二個較佳實施例的詳細說明中，將可 清楚的呈現。 在本新型被詳細描述之前，要注意的是，在以下的說 明内容中，類似的元件是以相同的編號來表示。 本新型的光罩可以是一種倍縮式光罩，即光罩上之線 路圖案可以5:1或4:1的比例微縮轉移至一如圖j所示具有 光阻層101的晶圓1〇〇上，並經由顯影製程後令該光阻 層1 〇1 ^/成與後續欲轉移在該晶圓1GG上之電路結構相同 之光阻圖S。要說明的是，該光罩的圖案係依據最終形成 在該晶® 100㈣路圖案設計，例如線路密度不@，或是 再依據該晶圓1〇〇的構成材料差異、表面形態差異等，而 製作形成具不同密集度（Proximity)或線寬分佈（Linearity)之 遮光圖案，因此不以圖中所示為限制。 參閱圖1、2，該光阻圖案係利用該微影曝光系統2〇〇 ，將該光罩置放於該微影曝光系統2〇〇中，並經一曝光光 1 "、、射’令通過該光罩的曝光光源201令該光阻層1〇1 的局。卩區域感光，最後再將該感光後之光阻層101經過顯 影製程後即可得到。 該微影曝光系統200是利用光學投影技術之步進機或 掃描步進機，包括將該曝光光源201聚集至光罩的聚焦透 7 M432133 镜202 ’以及令光罩上圖案成像至該晶圓loo上之投影透鏡 203等等組件’該曝光光源201可使用波長為248奈米或 193奈米之深紫外光（DUV) ’甚至是極深紫外光,(euv)。於 下述實把例中的光罩均是以4:1方式微縮轉移至該晶圓1 〇〇 作說明。 參閱圖4，本新型的一第一較佳實施例是提供一種光罩 3，用以令一蓋覆在一晶圓上之光阻層形成具有相同之線路 密度的光阻圖案為例作說明。 該預定形成之光阻圖案為具有多條彼此間隔設置並由 光阻材料構成的線路（Line)及多個由該些線路界定之間隙 (Space) ’該光罩3具有與該光阻圖案相對應之遮光圖案 ，且於圖4中所示之該光罩3僅為顯示部分結構。 該光罩3包含一透光基板31、多個遮光圖案32，及多 個透光區33。 所述遮光圖案32具有多條彼此相間隔並交錯地形成於 該透光基板31上的第一遮光層321及第二遮光層322，可 阻隔該曝光光源201 (見圖2)而令穿透過該等第一、二遮光 層321、322之光的能量低於該光阻層的感光能量，該每一 透光區33是由相鄰的一第一遮光層321及一第二遮光層 322所共同界定’允許該曝光光.源2〇1通過而令該光阻層感 光’且所述第一遮光層321與第二遮光層322具有不同厚 度。 要說明的是’間距的定義是指該形成的光阻圖案的一 條線（Line)的寬度加上其相鄰近的一個間隙（Space)的寬度 8 M432133 ，在本實施例中，在該晶圓上所欲成型之線路圖案（Pattern) 之間的間距（Pitch)是小於140奈米，因此，在4倍光罩的 圖案設計下，每一個第一遮光層321及每一個第二遮光層 322與各自相鄰的一透光區33所定義出的間距小於560奈 米。 進一步地說明，該些遮光圖案32可完全或部份阻隔該 曝光光源201穿透，其材料可選自：MoSi、ToSi2、Nb205 、Mo〇3、MoN、Cr203、TiN、ZrN、Ti02、TaN、Ta205、 Si02、NbN、Si3N4、ZrN、A1203N、MoSi、MoSiN、 MoSiON、MoSiO、CrOC、CrONC、Cr、Mo、Ti、Ta、鐵氧 化物、無機材料，或此等之一組合。 該透光基板31是由允許深紫外光照射穿透的材料構成 ，例如由石英玻璃（Quartz)所製成，而由於光罩製程中對於 該些遮光圖案 32的尺寸，例如：線寬一致性（CD uniformity)、鉻膜厚度一致性（Chromium thickness uniformity)或鉻膜截面輪廓（Edge profile)等皆需要嚴密控制 在規格範圍内，較佳地，所述遮光圖案32的高度是介於 5〜200奈米之間，且所述第一遮光層321與第二遮光層322 的厚度差不小於20A。 當該曝光光源201通過該光罩3時，由於該些透光區 33是由具有不同厚度之第一、二遮光層321、322所界定出 ，因此，當光線通過該每一透光區33時，鄰近該第一、二 遮光層321、322的邊緣會產生不同的繞射現象，而可改變 該透光區33及與該透光區33相鄰之第一、二遮光層321、 9 M432133 322區域的光強度對比，而可藉此修正習知該曝光光源2〇1 於通過具有相同厚度之遮光層丨21(見圖丨）的光罩後因繞射 現象而容易在高密度線路區造成形成的線路圖案產生頂部 表面積不足，或是有高度不足（Shortening)的問題，可讓形 成之光阻圖案得到修正，而提升曝光顯影製程容許程度。 值得一提的是，該些遮光圖案32亦可結合輔助線或利 用光學近階修正技術（Optical proximity correction)進行設計 修正，而該光罩3也可是一種相位移光罩或是二元式光罩 〇 此外，要再說明的是，由於該光阻圖案的線（Line)及間 隙（Space)的寬度會依據預計成形在該晶圓上之電路結構的 線路密度（Pattern density)不同而有所不同，換言之，該光罩 3的遮光圖案32及透光區33也會對應欲形成之該光阻圖案 而設計成具有不同寬度’且該些遮光圖案32則可對應不同 寬度的透光區33而呈現不同的厚度表現，而可藉此讓形成 之不同線路密度的圖案得到修正。 參閲圖5,本新型的一第二較佳實施例是提供一種光罩 4,用以令一蓋覆在一晶圓上之光阻層形成預定的光阻圖案 。於本較佳實施例中該光阻圖案為具有多條彼此間隔設置 並由光阻材料構成的線路（Line)及多個由該些線路界定之間 隙（Space)。圖5所示為該第二較佳實施例之光罩4的仰視 立體圖。 該光罩4包含一透光基板41，多個遮光圖案42，及多 10 M432133 個透光區43。 ~«光圖案42為相間隔地設置料透光基板41上 ，可阻隔料光光源2CU(見圖2)而令穿透過所述遮光圖案 42之光的能量低於該光阻層的感光能量，由於該透光基板 41及該些遮光圖案42的構成材料與該第—較佳實施例相同 因此不再資述。 ，、中該每-遮光圖案42具有一與該透光基板^表 面連接的第一遮光層421，及—實質自該第一遮光層似表 面的中央位置向遠離該透光基板41方向延伸的第二遮光層 422，所述透光區43 {由所述遮光圖案42所共同界定，允 許該曝光_ 2G1通過而令該光阻層感光；較佳地，該每 一個遮光«42與相鄰的—透絲43所定義出的間距是 小於560奈米。 ▲而在裏私便利性的考量下該第二遮光層422可選用與 該第-遮光層421不同姓刻選擇比的材料，例如：該第一 遮光層421可選自鉻，該第二遮光層似可選自氮化组 (蘭)。如此，則可經由適當的姓刻反應氣體的選用，當進 仃該第一遮光f 421的圖案化#刻時，該第二遮光層似 ^乍為硬質遮罩，而當進行第二遮光層422之圖案化姓刻 日守’其下之第-遮光層421可為姓刻訊號的终止層。此外 ，所述第二遮光層422的材質亦可使用與該第一遮光層421 相同的材質，例如：皆是今屈 "疋金屬鉻臈，但在蝕刻過程中便需 要精抗的勤刻時間控制，以成型出所需的厚度與立體型態 而由於光罩製程中對於該些遮光圖案42的尺寸，例如： 11 M432133 線寬一致性（CD uniformity)、鉻膜厚度一致性（Chromium thickness uniformity)或鉻膜截面輪靡（Edge profile)等皆需要 嚴密控制在規格範圍内，較佳地，該些遮光圖案42的高度 是介於5〜200奈米（nm)之間，且所述第一遮光層421與第 二遮光層422的厚度差不小於2〇A。 當該曝光光源201通過該光罩4時，會將所述遮光圖 案42轉移至該光阻層，之後再經過pEB及顯影步驟後即可 令該光阻層形成具有多條與所述遮光圖案42對應的線路 (line)，及多個對應該些透光區43且無光阻材料存在的間隙 (space)的光阻圖案。 本案利用該遮光圖案42的第一遮光層421與第二遮光 層422的厚度差異，讓通過所述透光區43的光線在鄰近該 第一、一遮光層421、422的邊緣產生不同的繞射現象，增 加光強度的對比’並用以微調該光罩4與該投影透鏡加( 見圖2)之間的距離，令光線在該綠層產生不同深度的聚 焦平面，而可藉以改善習知光線通過所述透光區122(見圖 υ時’因為繞射影響造成所述遮光層121(見圖u與透光區 122的光強度對比降低’及因為該光阻層在於咖等後續 ^程時，會因為光酸擴散程度的差異，令該光阻層在同一' 聚焦平面產生不同濃度的光酸’導致形成之間隙產生頸縮 (Μ—)的顯影圖案失真問題，而可提升曝光顯影製程容 許程度。 π β 參閱圖6,要說明的是，該些遮光圖案42還可旦有至 少一自該第一遮光f 421的兩端部423延伸的第三遮光層 12 M432133 424’且該第一遮光層421與該第三遮光層424的厚度差不 小於20人’而形成如圖6所示具有不同態樣的遮光單元42a 、42b、42c，該些遮光單元42a〜42c為配合半導體線路設計 而可單獨或混合存在，如此可令該遮光圖案42藉由該些遮 光單元42a、42b、42c厚度的差異性，改善習知該光阻層於 曝光顯影後形成之不同線路因為繞射造成光強度對比降低 所產生的顯影圖案失真的問題。 此外，參閱圖7,當欲利用一光罩上之遮光圖案於一光 阻層形成一凹槽時，則可結合前述圖5及圖6所示之該些 遮光圖案42，得到一具有如圖7所示之遮光圖案42，的光罩 4’’圖7所示為該光罩4,的仰視立體圖。 該光罩4,具有一呈矩形的透光區43，，該遮光圖案42, 具有一與該透光基板41(見圖5)連接並環圍該透光區43,的 第—遮光層421，、一環圍該第一遮光層421，的兩對邊的第 三遮光層424，，及一自該第一遮光層421，對應該透光區43, 的中間位置延伸的第二遮光層422，，而讓該遮光圖案42，的 中央及兩對邊具有較大厚度，藉以改善曝光形成後之凹槽 的關鍵尺寸誤差及形成之凹槽的周緣圓化（R〇unding)的問^ 。要說明的是，當預計形成的凹槽尺寸較小時，則可不需 再形成該第二遮光層422，，即只需令該遮光圖案42，於對應 該透光區43,的其中兩對邊具有較大厚度即可。 一 參閱圖8,本新型的一第三較佳實施例是提供一種光罩 5 ’包含一透光基板51、多個遮光圖案52，及多個透 53。. 13 M432133 該每-個遮光圖案52具有一與該透光基板51表面連 接並具有一第-厚度的第-_ 521及-自該第一遮光 層521鄰近該透光基板51的其中U邊延伸並與該透光基 板表面連接的第二遮光層522，該第二遮光層522具有 一第二厚度且該第二厚度小於該第-厚度，該些透光區53 具有複數個第-透光區531及複數個第二透光區532，且該 母個第透光區531是由相鄰的兩個第一遮光層52丨共 同界疋出該母個第一透光區532是由相鄰的兩個第二 遮光層522共同界定出，任一個遮光圖案52與相鄰的一第· 一透光區531定義出一第一間距S1，任一個遮光圖案52與 相鄰的一第二透絲532定義出一第二間距S2，該第一間 距si不同於該第二間距S2，且該第一、二間距si、^不 大於560奈米。較佳地，該些遮光圖案52的高度是介於 5〜200奈米（nm)之間，且所述第一遮光層521與第二遮光層 522的厚度差不小於2〇入。 利用该些遮光圖案52的第一遮光層521及第二遮光層 522的厚度差異，讓通過該些具有不同寬度的第一、二透光鲁 區531、532的光線在鄰近該第一遮光層521及第二遮光層 522的邊緣產生不同的繞射效應，使光線在該第一、二透光 區53卜532與第一、二遮光層521、522之間的強度對比 值產生差異，而可改善習知因為光線通過透光區122(見圖 1)的繞射影響’導致該光阻層於對應所述遮光層121(見圖 1)位置的區域也吸收到光線曝光而使後續對應形成的該些線 路產生頂部變形，表面積不足或是有高度不足（Sh〇rting)的 14 M432133 問題，可讓形成之線路圖案得到修正，而提升曝光顯影製 程容許程度。 此外要說明的是，圖5所示的該些遮光圖案42與圖 8所示的該些遮光圖案52可針對絲圖錢路的佈局設計 而同時應用於同一光罩。 综上所述’本新型該光罩主要藉由形成具有至少兩種 厚度之遮光圖案（第-、二遮光層），不僅可微調光軍與投影 透鏡之間的距離來達到產生不同深度的聚焦平面的目的， 以修正形成之光阻圖案的顯影解析度差異問題，並同時利 用該些遮光圖案的厚度差異’讓通過所述透光區的光線在 鄰近㈣透光區的邊緣產生不同的繞射效應’使光線在該 母一透光區及與該透光區相鄰之遮光圖案之間的光強度對 比值產生差異’而可改善習知因為光線遍過透光區122的 繞射影響’所導致的顯影圖樣失真的問題’而可提升曝光 顯影製程容許程度並可擴大對焦製程空間。 惟以上所述者’僅為本新型之較佳實施例而已，當不 能以此限定本新型實施之範圍’即大凡依本新型申^利 範圍及新型說明内容所作之簡單的等效變化與修都皆仍 屬本新型專利涵.蓋之範圍内。 【圖式簡單說明】 構； 圖1是-局部剖面示意圖’顯示習知的二元式光罩結 的 圖2是-不意圖’說明_微影曝光系統及其與光罩 相對關係； ~ 15 丄： 之光【二一示意圖’說明利用習知二元式光罩形成 九阻圖案顯影失真的態樣； 圖4是一局部剖面示意圖，說明本 一 ； 尤卓之弟 圖5是一仰視立體示意圖，說明本新型光罩之一第二 較佳實施例； 一 圖6是一局部立體示意圖’說明圖4中該遮光 不同實施態樣， 圖7疋一仰視立體不意圖，說明用於形成一 罩態樣；及 圖8是一局部剖面示意圖， 較佳實施例。 圖案的 凹槽的光 第 16The factor constructs a system for instant detection and feedback correction. In addition, currently in the semiconductor manufacturing process, it is determined that the product wafer is first selected for f, exposure moment (4) (10) Exp〇sure Matdx). To determine the best process focal length value. However, among the many methods disclosed, there is still no improvement in the problem of poor resolution of the development or defocusing of the micro-region due to the difference in line density or the unevenness of the flatness of the structure on the same wafer. [New content] Therefore, the purpose of this new type is to provide light for different semi-conducting 5 body and 60 graphic size or semiconductor design pattern loading, which can enhance the light in the lithography process space. cover. Further, another object of the present invention is to provide a photomask for improving the distortion distortion of a photoresist pattern formed after exposure and development of a photoresist layer. In the present invention, the photomask of the present invention is used to form a photoresist pattern corresponding to a semiconductor component line, comprising a light transmissive substrate, a plurality of light shielding patterns, and a plurality of light transmissive regions. The light-transmitting substrate allows an exposure light source to pass through, and the light-shielding patterns are spaced apart from the surface of the light-transmitting substrate to block the exposure light source so that the energy of the light passing through the light-shielding patterns is lower than the light-receiving photosensitive energy. The light-transmissive regions are defined by the light-shielding patterns, allowing the exposure light source to pass through, so that the light-resisting light-sensitive light-shielding patterns together constitute the photoresist pattern that is expected to be formed and have at least two thicknesses. In addition, the photomask of the present invention comprises a light transmissive substrate, a light shielding unit, and a plurality of light transmissive regions. The light-transmitting substrate allows an exposure light source to pass through, and the light-shielding unit is disposed on the surface of the light-transmitting substrate to block the exposure light source, so that the energy of the light passing through the light-shielding unit is lower than the light-receiving photosensitive energy, and the light-transmitting The region is defined by the light shielding unit and allows the exposure light source to pass through to make the photoresist photosensitive. The light shielding unit has a plurality of light shielding patterns spaced apart from each other and each of the light shielding patterns has at least two different thicknesses. The effect of the novel is that the reticle of the light-shielding pattern having at least two thicknesses causes the exposure light source to generate different optical phenomena when passing through the light-transmitting region of the reticle and form a focal plane of different depths in the photoresist layer. The M432133 is used to improve the distortion of the photoresist pattern formed by the photoresist layer after exposure and development, and the lithography process space can be enlarged. [Embodiment] The foregoing and other technical contents, features, and advantages of the present invention will be apparent from the detailed description of the preferred embodiments of the present invention. Before the present invention is described in detail, it is noted that in the following description, similar elements are denoted by the same reference numerals. The reticle of the present invention can be a doubling type reticle, that is, the line pattern on the reticle can be transferred to a wafer having the photoresist layer 101 as shown in FIG. j by a ratio of 5:1 or 4:1. After the development process, the photoresist layer 1 /1 ^ / is formed into the same photoresist pattern S as the subsequent circuit structure to be transferred on the wafer 1GG. It should be noted that the pattern of the reticle is based on the final pattern formed on the crystal 100 (four) road, for example, the line density is not @, or according to the composition difference of the wafer 1 差异, surface morphology difference, etc. The shading pattern is formed to have different Proximity or Linearity, and thus is not limited as shown in the figure. Referring to Figures 1 and 2, the photoresist pattern is used in the lithography exposure system 2, and the reticle is placed in the lithography exposure system 2, and subjected to an exposure light 1 ", shot ' Let the exposure light source 201 passing through the reticle align the photoresist layer 1〇1. The photosensitive region is sensitized, and finally the photosensitive photoresist layer 101 is subjected to a development process. The lithography exposure system 200 is a stepper or a scanning stepper using an optical projection technique, including concentrating the exposure light source 201 to a focus through a M 331 133 mirror 202 ′ and imaging the reticle onto the wafer The projection lens 203 on the loo and the like 'the exposure light source 201 can use deep ultraviolet light (DUV) having a wavelength of 248 nm or 193 nm or even extremely deep ultraviolet light (euv). The photomasks in the following examples are all transferred to the wafer 1 in a 4:1 manner for illustration. Referring to FIG. 4, a first preferred embodiment of the present invention provides a photomask 3 for forming a photoresist pattern having a same line density on a photoresist layer overlying a wafer. . The predetermined photoresist pattern has a plurality of lines spaced apart from each other and composed of a photoresist material and a plurality of spaces defined by the lines. The mask 3 has a pattern with the photoresist pattern. Corresponding opaque patterns, and the reticle 3 shown in FIG. 4 is only a display portion structure. The reticle 3 includes a light transmissive substrate 31, a plurality of light shielding patterns 32, and a plurality of light transmissive regions 33. The light shielding pattern 32 has a plurality of first light shielding layers 321 and a second light shielding layer 322 which are spaced apart from each other and are alternately formed on the transparent substrate 31. The exposure light source 201 (see FIG. 2) can be blocked and penetrated. The light of the first and second light shielding layers 321 and 322 is lower than the light energy of the photoresist layer, and each of the light transmission regions 33 is formed by an adjacent first light shielding layer 321 and a second light shielding layer 322. The first light-shielding layer 321 and the second light-shielding layer 322 have different thicknesses, which are defined as 'allowing the exposure light. The source 2〇1 passes to make the photoresist layer photosensitive'. It should be noted that 'the definition of the pitch refers to the width of one line of the formed photoresist pattern plus the width of a space adjacent to it, 8 M432133. In this embodiment, the wafer is The pitch between the patterns to be formed is less than 140 nm, and therefore, each of the first light shielding layer 321 and each of the second light shielding layers 322 under the pattern design of the 4 times mask. The spacing defined by a light transmissive region 33 adjacent thereto is less than 560 nm. Further, the light shielding patterns 32 may completely or partially block the penetration of the exposure light source 201, and the material thereof may be selected from the group consisting of: MoSi, ToSi2, Nb205, Mo〇3, MoN, Cr203, TiN, ZrN, Ti02, TaN, Ta205, SiO2, NbN, Si3N4, ZrN, A1203N, MoSi, MoSiN, MoSiON, MoSiO, CrOC, CrONC, Cr, Mo, Ti, Ta, iron oxide, inorganic material, or a combination thereof. The light-transmitting substrate 31 is made of a material that allows penetration of deep ultraviolet light, for example, made of quartz glass (Quartz), and the size of the light-shielding patterns 32 in the mask process, for example, line width uniformity (CD uniformity), Chromium thickness uniformity or chrome film profile profile, etc., need to be strictly controlled within the specification range. Preferably, the height of the light shielding pattern 32 is between 5~ Between 200 nm, and the difference between the first light shielding layer 321 and the second light shielding layer 322 is not less than 20A. When the exposure light source 201 passes through the reticle 3, since the light-transmitting regions 33 are defined by the first and second light-shielding layers 321, 322 having different thicknesses, when light passes through each of the light-transmitting regions 33 When the edges of the first and second light shielding layers 321 and 322 are adjacent to each other, different diffraction phenomena may be generated, and the light transmitting region 33 and the first and second light shielding layers 321 and 9 adjacent to the light transmitting region 33 may be changed. The light intensity contrast of the M432133 322 area, and the exposure light source 2〇1 can be modified to pass through the mask having the same thickness of the light shielding layer 丨21 (see FIG. 后), which is easy to be in the high-density line due to the diffraction phenomenon. The formation of the line pattern causes insufficient top surface area or a problem of shortening, which can correct the formed photoresist pattern and increase the tolerance of the exposure and development process. It is worth mentioning that the light shielding patterns 32 can also be designed and modified by using an auxiliary line or by an optical proximity correction technique, and the mask 3 can also be a phase shift mask or a binary light. In addition, it is to be noted that the width of the line and the space of the photoresist pattern may vary depending on the circuit density of the circuit structure expected to be formed on the wafer. Differently, in other words, the light-shielding pattern 32 and the light-transmitting region 33 of the mask 3 are also designed to have different widths corresponding to the photoresist pattern to be formed, and the light-shielding patterns 32 can correspond to the light-transmitting regions 33 of different widths. Instead, the thicknesses are represented by different thicknesses, and the patterns of the different line densities formed can be corrected. Referring to Figure 5, a second preferred embodiment of the present invention provides a reticle 4 for forming a predetermined photoresist pattern over a photoresist layer overlying a wafer. In the preferred embodiment, the photoresist pattern has a plurality of lines spaced apart from each other and composed of a photoresist material and a plurality of spaces defined by the lines. Fig. 5 is a bottom perspective view of the reticle 4 of the second preferred embodiment. The reticle 4 comprises a light-transmissive substrate 41, a plurality of light-shielding patterns 42, and a plurality of 10,432,133 light-transmissive regions 43. ~«The light pattern 42 is disposed on the material transparent substrate 41 at intervals, and blocks the light source 2CU (see FIG. 2) so that the energy of the light penetrating the light shielding pattern 42 is lower than the photosensitive energy of the photoresist layer. Since the constituent materials of the light-transmitting substrate 41 and the light-shielding patterns 42 are the same as those of the first preferred embodiment, they will not be described. The first light-shielding pattern 42 has a first light-shielding layer 421 connected to the surface of the light-transmitting substrate, and substantially extends from a central position of the surface of the first light-shielding layer toward the light-transmitting substrate 41. a second light shielding layer 422, the light transmissive region 43 is commonly defined by the light shielding pattern 42 to allow the exposure _ 2G1 to pass through to make the photoresist layer photosensitive; preferably, each of the light shielding layers 42 and adjacent The spacing defined by the filament 43 is less than 560 nm. ▲ The material of the second light-shielding layer 422 may be different from the first light-shielding layer 421. For example, the first light-shielding layer 421 may be selected from chrome, and the second light-shielding may be selected. The layer may be selected from the group consisting of nitrides (blue). In this way, the selection of the reactive gas by the appropriate surname may be used. When the patterning of the first light-shielding 421 is performed, the second light-shielding layer may be a hard mask, and when the second light-shielding layer is performed. The patterned surname of 422 is the next step - the shading layer 421 can be the termination layer of the surname signal. In addition, the material of the second light shielding layer 422 may also be the same material as that of the first light shielding layer 421, for example, both of the present and the metal chrome enamel, but the precision resistance is required during the etching process. Time control to shape the desired thickness and stereotype due to the dimensions of the opaque pattern 42 in the reticle process, for example: 11 M432133 line uniformity (CD uniformity), chrome film thickness uniformity (Chromium thickness) The uniformity) or the chrome film section profile and the like need to be tightly controlled within the specification range. Preferably, the heights of the light shielding patterns 42 are between 5 and 200 nanometers (nm), and the The difference in thickness between the first light shielding layer 421 and the second light shielding layer 422 is not less than 2 〇A. When the exposure light source 201 passes through the reticle 4, the light shielding pattern 42 is transferred to the photoresist layer, and then after the pEB and the development step, the photoresist layer is formed into a plurality of patterns and the light shielding pattern. 42 corresponds to a line, and a plurality of photoresist patterns corresponding to the light-transmitting regions 43 and having no space in which the photoresist material exists. In this case, the difference in thickness between the first light shielding layer 421 and the second light shielding layer 422 of the light shielding pattern 42 is such that the light passing through the light transmission region 43 produces different windings adjacent to the edges of the first and first light shielding layers 421 and 422. Shooting phenomenon, increasing the contrast of light intensity' and using it to fine-tune the distance between the reticle 4 and the projection lens (see Figure 2), so that the light produces different depths of focus in the green layer, thereby improving the conventional knowledge. The light passes through the light-transmitting region 122 (see FIG. '' because the light-shielding layer 121 is caused by the diffraction effect (the light intensity of the light-transmitting region 122 is reduced) and because the photoresist layer is in the subsequent During the process, due to the difference in the degree of photoacid diffusion, the photoresist layer produces different concentrations of photoacid in the same 'focus plane', resulting in a problem of distortion of the developing pattern caused by the gap formed in the gap formed, and the exposure can be improved. The degree of tolerance of the development process is π β. Referring to FIG. 6 , the light shielding patterns 42 may have at least one third light shielding layer 12 M432133 424 ′ extending from the both end portions 423 of the first light shielding f 421 . The first light shielding layer 421 and the third The light layer 424 has a thickness difference of not less than 20 Å, and the light-shielding units 42a, 42b, and 42c having different states as shown in FIG. 6 are formed, and the light-shielding units 42a to 42c may be used alone or in combination for the design of the semiconductor circuit. Therefore, the shading pattern 42 can improve the development of the different lines formed by the photoresist layer after exposure and development due to the difference in thickness of the light-shielding units 42a, 42b, and 42c. In addition, referring to FIG. 7, when a recess is formed on a photoresist layer by using a light-shielding pattern on a mask, the light-shielding patterns 42 shown in FIG. 5 and FIG. 6 may be combined. A reticle 4'' having a light-shielding pattern 42 as shown in FIG. 7 is shown in FIG. 7. FIG. 7 is a bottom perspective view of the reticle 4. The reticle 4 has a rectangular transparent area 43. The light-shielding pattern 42 has a first light-shielding layer 421 connected to the transparent substrate 41 (see FIG. 5) and surrounding the light-transmitting region 43, and a second side of the first light-shielding layer 421 The three light shielding layers 424, and one from the first light shielding layer 421 correspond to the light transmitting region 43, a second light shielding layer 422 extending in the middle position, and the center and the two opposite sides of the light shielding pattern 42 have a large thickness, thereby improving the critical dimension error of the groove after the exposure is formed and the circumferential circle of the formed groove R 〇 ing 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 One of the two opposite sides of the light transmissive area 43 may have a large thickness. Referring to FIG. 8, a third preferred embodiment of the present invention provides a photomask 5' including a transparent substrate 51 and a plurality of shadings. Pattern 52, and a plurality of transparent 53. 13 M432133, each of the light shielding patterns 52 has a first-th 521 connected to the surface of the transparent substrate 51 and having a first thickness, and a U-side from the first light shielding layer 521 adjacent to the transparent substrate 51 a second light shielding layer 522 extending from the surface of the transparent substrate, the second light shielding layer 522 has a second thickness and the second thickness is smaller than the first thickness, and the plurality of light transmission regions 53 have a plurality of first a light region 531 and a plurality of second light transmitting regions 532, and the mother light transmitting regions 531 are separated by two adjacent first light shielding layers 52, and the mother first light transmitting regions 532 are The two adjacent second light shielding layers 522 are defined together, and any one of the light shielding patterns 52 defines a first spacing S1 with the adjacent one light transmitting region 531, and any one of the light shielding patterns 52 and the adjacent one The second wire 532 defines a second spacing S2 that is different from the second spacing S2, and the first and second spacings si, ^ are no greater than 560 nm. Preferably, the height of the light shielding patterns 52 is between 5 and 200 nanometers (nm), and the difference between the first light shielding layer 521 and the second light shielding layer 522 is not less than 2 inches. Using the difference in thickness between the first light shielding layer 521 and the second light shielding layer 522 of the light shielding patterns 52, the light passing through the first and second light transmitting regions 531 and 532 having different widths is adjacent to the first light shielding layer. The edges of the 521 and the second light shielding layer 522 generate different diffraction effects, so that the intensity contrast between the first and second light transmitting regions 53 532 and the first and second light shielding layers 521 and 522 is different. It can be improved that the light is transmitted through the light transmissive region 122 (see FIG. 1), causing the photoresist layer to absorb the light exposure in the region corresponding to the position of the light shielding layer 121 (see FIG. 1). The formation of the lines produces a top deformation, insufficient surface area or a low height (Sh〇rting) 14 M432133 problem, which allows the formed line pattern to be corrected to increase the tolerance of the exposure development process. It should be noted that the light shielding patterns 42 shown in FIG. 5 and the light shielding patterns 52 shown in FIG. 8 can be simultaneously applied to the same mask for the layout design of the silk road. In summary, the reticle of the present invention mainly achieves different depths by forming a light-shielding pattern (first and second light-shielding layers) having at least two thicknesses, not only fine-tuning the distance between the light and the projection lens. The purpose of the plane is to correct the difference in development resolution of the formed photoresist pattern, and at the same time utilize the thickness difference of the light-shielding patterns to make the light passing through the light-transmitting region produce different windings at the edge of the adjacent (four) light-transmitting region The radiation effect 'different light intensity contrast between the light-transmitting region of the mother and the light-shielding pattern adjacent to the light-transmitting region' can improve the conventional diffraction effect of light passing through the light-transmitting region 122. 'The problem of distortion of the developed pattern caused by 'can increase the tolerance of the exposure and development process and expand the focus process space. However, the above description is only a preferred embodiment of the present invention, and when it is not possible to limit the scope of the present invention, it is a simple equivalent change and repair of the novel scope and the novel description. All of them are still within the scope of this new patent culvert. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial cross-sectional view showing a conventional binary reticle. FIG. 2 is a non-intentional description _ lithography exposure system and its relationship with a reticle;丄: The light [2D schematic] illustrates the use of the conventional binary mask to form a nine-resistance pattern development distortion; Figure 4 is a partial cross-sectional view illustrating the first; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 6 is a partial perspective view showing a different embodiment of the shading in FIG. 4, and FIG. 7 is a perspective view of the present invention. A cover view; and Figure 8 is a partial cross-sectional view, a preferred embodiment. Patterned grooved light 16th