201234120 六、發明說明： 【發明所屬之技術領域】 本發明-般關於微影投射曝光裝置之照射系統，尤其是關 於包含微鏡陣列或其他偏光元件陣列之裝置。 【先前技術】 微影(亦稱為光學微f彡或嶋鄉)是—種製储體電路、液 晶顯示器以及其他微結構裝置的技術。微影製程結合㈣製程 用於圖案化已形成於基板(例如石夕晶圓)上之薄膜堆疊。製造各層 時三晶圓首先塗佈光阻，光阻為對特定波長之光敏感的材料。 接著’上面有光阻的晶圓在投射曝光裝置t透過光罩以投射光 曝光。光罩含有要成像到光_電路随。在曝光後，顯影光 =產生對就罩所含電路圖案的影像。然後侧製程將電路 ，案轉印到晶®上㈣輯疊。最後，移除光阻。以不同的光 罩重複此程序得到多層微結構化組件。 投射曝光襄置典型包含照射系統，其照射光罩上可且有例 的場。投射曝光裝置更包含用於對準i罩的 於、〇、：、罩上的照射場成像到光阻的投影物鏡(有時稱「透 ’兄」以及用於對準塗有光阻之晶圓的晶圓對準台。 j圓上 而其 應0 微發展過程中之-個重要目標在於能在蓋 尺寸越來越小的結構。小結構能導致高積集度， 吊對利用此類裝置製造之微結構組件效能產生有利的效 在過去為了達到此目標已有各種方案。一個方案為降低用 201234120 於將電路圖案成像到光阻所用之投射光的波長。此方案利用的 事實為可微影界定之特徵的最小尺寸大約正比於投射光的波 長。因此’此類裝置的製造商致力於使用波長越來越短的投射 光。目前所用最短的波長為248 nm、193 nm以及157 nm，因 此是在深紫外光(DUV)或真空紫外光(VUV)之超紫外光譜範 圍。下一世代商用裝置將使用具有甚至在極紫外光範圍(EUV) 之更短的13.5nm波長之投射光。EUV裝置含有反射鏡而不是透 鏡，因為透鏡會吸收幾乎所有的光。 另一方案是改善光罩的照射。理想上，投射曝光裝置的照 射系統以具有良好界定之空間及肖輻照分布的投射光來照射 射場的各點。—照分布—詞描述朝光罩上特定點匯 聚之先束的總光能如何在構成光束之光線的各種方向中分布。201234120 VI. Description of the Invention: TECHNICAL FIELD OF THE INVENTION The present invention generally relates to illumination systems for lithographic projection exposure apparatus, and more particularly to apparatus comprising an array of micromirrors or other array of polarizing elements. [Prior Art] The lithography (also known as optical micro-f彡 or 嶋乡) is a technique for seed storage circuits, liquid crystal displays, and other microstructure devices. The lithography process is combined with a (four) process for patterning a thin film stack that has been formed on a substrate, such as a Shihwa wafer. The three wafers are first coated with photoresist when the layers are fabricated, and the photoresist is a material that is sensitive to light of a particular wavelength. Then, the wafer having the photoresist thereon is exposed to the projected light through the mask at the projection exposure device t. The reticle contains the image to be imaged to the light_circuit. After exposure, the developed light = produces an image of the circuit pattern contained in the cover. Then the side process transfers the circuit to the wafer (4). Finally, remove the photoresist. Repeat this procedure with different reticle to obtain a multilayer microstructured assembly. Projection exposure devices typically include an illumination system that illuminates a field on the reticle. The projection exposure apparatus further includes a projection objective for aligning the illumination field of the i-mask, the imaging field on the cover to the photoresist (sometimes referred to as "through" brother, and for aligning the photoresist-coated crystal Round wafer alignment table. The circle is on the circle and it should be in the process of development. An important goal is to be able to make the structure of the cover smaller and smaller. Small structure can lead to high integration, and the use of this type The effectiveness of the microstructure component manufacturing of the device has produced advantageous effects. In the past, various solutions have been made to achieve this goal. One solution is to reduce the wavelength of the projected light used to image the circuit pattern to the photoresist with 201234120. This scheme utilizes the fact that The minimum size of the feature defined by lithography is approximately proportional to the wavelength of the projected light. Therefore, manufacturers of such devices are committed to using projected light with shorter and shorter wavelengths. The shortest wavelengths currently used are 248 nm, 193 nm, and 157 nm. Therefore, it is in the ultra-ultraviolet spectral range of deep ultraviolet (DUV) or vacuum ultraviolet (VUV). The next generation of commercial devices will use projection light with a shorter wavelength of 13.5 nm even in the extreme ultraviolet range (EUV). EUV The device contains a mirror instead of a lens because the lens absorbs almost all of the light. Another solution is to improve the illumination of the reticle. Ideally, the illumination system of the projection exposure device illuminates with a well defined space and a irradiance distribution of the projected light. The points of the field - the distribution - the words describe how the total light energy of the first beam that converges at a particular point on the reticle is distributed in various directions of the light constituting the beam.
，，，口\；取 大彈性， 習知技術士 ·^一 角輻照分布， 產生不同角幸畐 定。為了達到在光罩平面中 已提出使用反射鏡陣列來決 201234120 定曈表面中的輻照分布。 於EP 1 262 836 A1中，反射鏡陣列實施為包含超過1〇〇〇 個顯微反射鏡之微機電系統(MEMS)。各反射鏡可以兩個正交傾 斜軸來傾斜。因此，入射到此類反射鏡裝置之輻射可反射到幾 乎任何想要的半球體方向。設置在反射鏡陣列及曈表面之間的 聚光透鏡將反射鏡所產生的反射角轉譯成在瞳表面中的位置。 此照射系統可以複數光點方式照射瞳表面，其中各光點與一個 特定反射鏡相關，且可藉由傾斜相關的反射鏡而自由地在暗类 面範圍移動。 使用反射鏡陣列的類似照射系統可由US 2006/0087634,,, 口\; Take great elasticity, the known technology technicians · ^ a corner irradiation distribution, producing different angles. In order to achieve the use of a mirror array in the reticle plane, it is proposed to determine the irradiance distribution in the surface of the 201234120. In EP 1 262 836 A1, the mirror array is embodied as a microelectromechanical system (MEMS) comprising more than 1 显微 micro mirrors. Each mirror can be tilted by two orthogonal tilt axes. Therefore, the radiation incident on such a mirror device can be reflected to almost any desired hemispherical direction. A concentrating lens disposed between the mirror array and the haptic surface translates the angle of reflection produced by the mirror into a position in the haptic surface. The illumination system can illuminate the pupil surface in a plurality of spots, wherein each spot is associated with a particular mirror and can be freely moved over the dark surface range by tilting the associated mirror. A similar illumination system using a mirror array can be used by US 2006/0087634
Al、US 7 061 582 B2 及 WO 2005/026843 A2 得知。 為了在曈表面中達到所需的輻照分布，會希望有非常大量 (150000個或更多）的微光點，而該些微光點可借助反射鏡陣列 自由地配置在瞳表面中。然而’因為各種理由，包含如此多反 射鏡之反射鏡陣列的製造及運作是不可行的或尚不可行的。舉 例而言，在此裝置的微型化、可用空間、以及反射鏡傾斜移動 的即時控制方面有許多的限制。 【發明内容】 ^此/’本發明實施例之目的在於提供—種微影投射曝光裝 置之域糸統，其可更精確地在曈表面中產生所需的韓照分布。 根據本發明實施例’藉由—種照射系統來達成此目的，此 201234120 照射系統包含光學元件之分光陣列，其中各光學元件具有正光 學焦度(positive optical p〇wer)以及產生專門與該些光學元件相 關之匯聚光束。照射系統更包含表面，例如瞳表面或緊鄰設置 在瞳表面附近之集光器前之表面或在集光器前之表面Ϊ照射系 統亦包含空間光調變器，其設置在分光陣列及該表面之間，並 組·4成用於改變在表面上之輻照分布。空間光調變器包含複數 個反射或穿透偏光元件之偏光陣列。各偏光元件係關聯於分光 陣列之至少其中一個光學元件，並組態成將關聯的光學元件產 生的匯聚光束偏轉了偏轉角度，此偏轉角度可因應控制訊號改 變。再者’偏光元件將經偏轉的光束朝向表面導引，經偏轉的 光束在該處產生具有光點尺寸之光點。根據本發明，分光陣列 之至少兩個光學元件具有不同的光學性質，使得與至少兩個光 學元件關聯的光點之光點尺寸係不同。 因此’根據本發明實施例之照射系缝在表面產生且有不 同光點尺寸的光點。此為有利的，因為可組合較大的光點而 在表面可得到較大的準連續照射區域。而較小的光點可用於完 成f琢磨此區域的輪靡，而精確地符合所需的輕照分布。舉例 而。有非*小的光點而言，可產生要照射區域的圓形邊 但疋另-方面以給定的非常小光點數目而言，則不可能連 交大的區域。只有提供較小及較大光點可產生具有所 而輪廓的較大區域。 分光陣狀光學元件可騎射式絲元件(例如微透鏡)、反 =光學TL件(例如微鏡）、錢射光學元件。光學元件的正 …、又思味著可以具有匯聚效應’如正透鏡、凹面鏡、或具有聚 201234120 焦效應之繞射光學元件的案例 偏光7G件可為可傾斜的反射鏡，而偏光陣列則可 動 器，用於傾斜反射鏡。然而’偏光元件亦可包含利用光電或聲 光效應的穿透元件。減航件巾，可將射材料分別暴露於 電場或超音波方式，來改變騎率。_這些效翻於產 照射光導向各種方向之指標光栅。 ; ’ 至少兩個光學元件的不同光學性質可為光學隹产 兩個光學元㈣絲缝不同，_效應也㈣^此 元件射出的絲具有抑_光分布。由於光柄角光分布在 遠場中或借助聚光ϋ轉變成絲照分布，具林同 光學元件所產生的光點在表面會具有不同的尺寸。若僅^隹 ^變但是光學元件尺寸不變，則在表面巾的絲 = 變’但形狀不變。. & 分光陣列之光學元件通常具有入光面及出光面。若 個光學元狀人光面及/絲具有不__ ^個光學元件有㈣絲性質。此利㈣事實為人光面及/出 光面之_也對減學7G件射出之光柄角光分布有所影塑。Al, US 7 061 582 B2 and WO 2005/026843 A2 are known. In order to achieve the desired irradiance distribution in the ruthenium surface, it may be desirable to have a very large number (150,000 or more) of micro-light spots that are freely configurable in the ruthenium surface by means of a mirror array. However, the manufacture and operation of mirror arrays containing such multiple mirrors is not feasible or feasible for a variety of reasons. For example, there are many limitations in the miniaturization of the device, the available space, and the immediate control of the tilting movement of the mirror. SUMMARY OF THE INVENTION It is an object of the present invention to provide a field system for a lithographic projection exposure apparatus that more accurately produces a desired luminescence distribution in a ruthenium surface. This object is achieved by an illumination system according to an embodiment of the invention, the 201234120 illumination system comprising a spectroscopic array of optical elements, wherein each optical element has a positive optical power and a specific optical Converging beams associated with optical components. The illumination system further comprises a surface, such as a surface of the crucible or a surface immediately adjacent to the collector disposed near the surface of the crucible or a surface in front of the collector. The illumination system also includes a spatial light modulator disposed on the spectroscopic array and the surface Between and 40% is used to change the irradiance distribution on the surface. A spatial light modulator includes a plurality of polarizing arrays that reflect or penetrate polarizing elements. Each of the polarizing elements is associated with at least one of the optical elements of the beam splitting array and is configured to deflect the concentrated beam of light produced by the associated optical element by a deflection angle that is responsive to the control signal. Further, the polarizing element directs the deflected beam toward the surface where the deflected beam produces a spot having a spot size. According to the invention, at least two optical elements of the spectroscopic array have different optical properties such that the spot size of the spot associated with at least two of the optical elements is different. Thus, the illuminating seam according to an embodiment of the present invention produces spots having different spot sizes on the surface. This is advantageous because a larger spot of light can be combined to provide a larger quasi-continuous illumination area on the surface. A smaller spot can be used to complete the rim of the area, precisely matching the desired light distribution. For example. In the case of non-small spots, a circular edge to be illuminated can be produced. However, in terms of the number of very small spots given, it is impossible to connect large areas. Only providing smaller and larger spots produces a larger area with a contour. The spectroscopic optical element can be a riding wire element (for example, a microlens), a reverse optical t-piece (for example, a micromirror), or a money-emitting optical element. The optical component is...something that can have a convergence effect such as a positive lens, a concave mirror, or a diffractive optical element with a poly 201234120 focal effect. The case polarized 7G piece can be a tiltable mirror, while the polarizing array is movable. For tilting the mirror. However, the polarizing element may also comprise a penetrating element that utilizes an optoelectronic or acousto-optic effect. The airfoil can be used to change the ride rate by exposing the shot material to an electric field or ultrasonic method. _ These effects turn to the index grating that produces illumination in all directions. The different optical properties of at least two optical components can be optically produced. The two optical elements (4) are different in the silk seam, and the _ effect is also (4). The filaments emitted by the component have a light-reducing distribution. Since the optical stalk angular light is distributed in the far field or converted into a silk distribution by means of a collecting ray, the light spots produced by the same optical elements have different sizes on the surface. If only the size of the optical element is changed, the wire of the surface towel is changed to 'the shape' but the shape is unchanged. & The optical elements of the spectroscopic array usually have a light incident surface and a light exit surface. If an optical element has a smooth surface and/or a wire, it has no (four) silk properties. This benefit (4) is the fact that the smooth and/or shiny surface of the person is also influenced by the distribution of the light handle angle of the 7G piece.
然後，在遠場中或利用額外的聚光器，將變化的角光ς 成在表面的不同光點尺寸。 I 舉例而言，至少兩個光學元件其中之一者之入光或出光面 可具有矩形财卩’以及至少兩個光學元件之其中另—者之 或出光面可具有人邊形輪靡。因為對稱的理由，人光面或出光 201234120 =樣的輪練佳。但自齡有各種其他造成不同光點尺寸之 成何狀〇 光學7L件可設置於分糾列巾，使得光學元件之入光面或 面盥t週期性随方式設置’其中矩形輪廓的人光面或出光 面與八邊形的入光面或出光面交替設置。 學性= f少五個光學元件有不同的光 -I 有至少五種不同光點尺寸的光點。 合產生所綠=日加將光點組 ，射錢可包含辆，其完全_分光陣列 及吸收的話，使所有照到進二 光損失，對投射_:=有=在分光㈣沒有 分光陣列之進人表面二忽，齡的話，光縣均勻地照射 照僅依據相關 光i面件此優勢是因為特定光束所產生的光點輻 中的位置。Μ件料學性質，只斜賊在分光陣列 <定義> 光」一詞表示任何 電磁輪辦’尤其是可見光、UV、DUV、 201234120 VUV及EUV光、以及X光線。 於此所用之「光線」一詞表示可以線描述前進路徑的光。 於此所用之「光線束」一詞表示在場平面中具有共同原點 的複數光線。 於此所用之「光束」一詞表示通過特定透鏡或其他光學元 件的光。 於此所用之「光學光柵元件」一詞表示任何光學元件，例 如透鏡、稜鏡或繞射光學元件，係與其他光學光柵元件設置在 一起，而產生或維持複數相鄰的光學通道。 於此所用之「集光器」一詞表示增加Α/^.α之乘積的光學系 統，其中為數值孔徑，而α為照射的場面積。 ，於此所用之「聚光器」一詞表示在兩個平面(例如場平面及 曈平面）間建立(至少大約)傅立㈣係之光學元件或絲系統。 —於此所用之「空間輻照分布」一詞表示總輻照度在光照到 的實際或虛擬表面上是如何的變化。通常空間輻照分布可以函 式來描述，其中χ、少為點在表面中的空間座標。若運用 到場平面，㈣触分布需要整合_級賴產生魄照度。 於此所用之「角輕照分布」一詞表示光線束之輕照度依據 10 201234120 度如何變化。通常_分布可以函式 八才呈* = Γ、α 〃為指述光線方向之角座標。若角㈣ 刀布具有場相依性，4亦為場座標的函式，即照 於此所用之「表面」一詞表示在三維空間中的任何 =表面可為物體的部分，或可與物體完全分開，通ς 平面或曈平面之案例。 場 ㈣之「光學焦度」—詞表示光學元件對光具有發散 或匯聚效應的能力。因此’正光學焦度具 學焦度具有發散光學效應。 ％負先 /於此所用之「匯聚效應」_詞表示不管人射S是發散、平 灯或已匯聚，g聚性增加。若人射光是發散的，聽聚性必須 加到從光學元件射出的光束至少是些為匯聚的程度。 、 於此所用之「光點尺寸」一詞表示與一個偏光元件相關的 特定光束在表面上照射的總面積。光點尺寸的量測單位通常為 mm2。 【實施方式】 投射曝光裝置之一般性架構 圖1為根據本發明之投射曝光裝置1〇之極簡化透視圖，投 射曝光裝置10包含產生投射光束之照射系統12。投射光束照射 11 201234120 例，Ϊ:二徵且圖案18之光罩16上的場14。於此實施 本與具有環片段形狀’其不包含投射曝光裝置10之 子 。然而’亦考量其他形狀的照射場14，例如矩形。 、&有複數透鏡21之投影物鏡20將照射場14内的圖案a 成像到由基板24所支樓的感光層22(例如光阻）。基板24可由 =曰曰圓形成，並没置於晶圓台(未顯示)上，使得感光層的頂 表面精確地位於投影物鏡2〇之影像平面中。光罩16利用光罩 台(未顯示)定位於投影物鏡20的物件平面中。由於投影物鏡2〇 具有放大率β，且|別< 1，所以將照射場14内圖案18的縮 像18投射到感光層22 ^ 於投射期間，光罩16及基板24沿著掃瞄方向移動，掃瞄 方向與圖1所示之Υ方向相同。然後’照射場14掃描過光 16，而可連續地成像比照射場14還大的圖案化區域。基板 與光罩16間的速度比等於投影物鏡20的放大率沒。若"投影 鏡20反轉(invert)影像(々< 〇)，則光草16與基板24移= 反方向，如圖1之箭頭A1及A2所示。然而’本發明亦可用於 步進器(stepper)工具，其中在光罩投射的期間，光罩16與美板 24不移動。 ” 土 II. 照身f,糸統之—般性架構 圖2為圖1之照射系統12喊面圖。圖2的圖式 未依比例繪示。尤其是指說僅由一個或非常少的光學元^、 * ' Γ\| >ρζ. 12 201234120 的光學單70。實際上，這些單元可包含明顯更多的透鏡及 其他光學元件。 30會二射糸統12包含殼體29及光源30，亦即於此實施例光源 ^成準分子雷射。光源3〇發射具有波長約193nm的投射 、也考量其他類型的光源％及其他的波例如撕肺或 157nm) 〇 击實施例巾，絲3G所發射的光束進人擴張光束的光 读^ 3疋32。為達此目的，光束擴張單元32可包含例如數個 =甘'面鏡。從光束猶單元32射出的擴張光束以標號％ 不’，、具有低發散性，亦即幾乎為準直的。 束34 束34進人分光陣列36，分光_ 36將擴張光 =刀成後數個別的匯聚光束LB。為簡明之故，於圖2中僅 釋匯聚光束心分光_36於下參考會更 然後，匯聚光束LB前進通過空間光 之後的曈平面中產生可變的空間輻H 8、用於在 光調變器38包含微鏡42的陣列4。，微鏡=二空間 地繞兩個正交軸傾斜。致動H受 ’_可借助致動益獨立 元43連接整體的系統控制器邾。工早兀43所控制，而控制單 圖3為陣列40的透視圖，颟干1 如何依據光束LB1、啦照到微鏡^道匯聚光束⑽伽 傾斜角而被反射到不同 201234120 方向。於圖2及圖3中，陣列40包含只有6χ6個微鏡42。實 際上陣列40可包含數百個或甚至數千個微鏡42。 參考圖2,空間光調變器38更包含稜鏡46，其具有第一平 面表面48a及第二平面表面48b，兩者皆相對於照射系統12之 光學軸OA傾斜。於傾斜的表面48a、48b ’光束LB受到全内 反射方式的反射。第一表面48a朝向微鏡陣列4〇之微鏡42反 射照到的光束LB，而第二表面48b將微鏡42反射的光束朝向 稜鏡46的出射面49導引。因此，光束LB的方向以及從稜鏡 46之出射面49射出之光的角輻照分布，可藉由個別地傾斜陣列 40之微鏡42而改變。關於空間光調變器38之更多細節可參考 例如 US 2009/0115990 A1。 空間光調變器38所產生的角輻照分布借助第一聚光器5〇 轉變成空間輻照分布’其中第-聚光器5〇將照射光束LB朝向 集光器52導引。於此實施例中，集光器52包含兩個光學光栅 板54a、54b，各含有圓柱形微透鏡的兩個正交陣列。集光器π 在照射系統12之後續曈平面56中產生複數二級光源。第二聚 光裔58在瞠平面56及場光闌平面6〇之間建立傅立葉關係，其 中可調式場光闌62設置於光闌平面6〇。第二聚光器58將二級 光源射出之光束疊置(superimpose)於場光闌平面6〇中，而非常 均勻地照射場光闌平面60。 %光闌物鏡64將場光闌平面6〇成像到光罩平面66，其中 光罩16借助光罩台（未顯示)設置於光罩平面66中。再者，可調 式土歹光闌62藉此成像到光罩平面66上，且至少定義照射場μ 201234120 沿掃瞄方面γ延伸之短側邊。 集光器52前的輻照分布決定在瞳平面56中的輻照分 因而決定在場光闌平面60及光罩平面66中的角輕:^。件 助控制單元43細心地設定反射鏡陣列4〇之微鏡42的傾 曰 因而可快速地在光罩平面66產生幾乎是任何任意的角輪= 布。因此’可使光罩平面66中的角輻照分布快速地配合光罩、f 所含的圖案18。利用最佳化的角輻照分布，可更精確地將 18成像到感光層22。 一、 III. 分光陣列-光學焦度變化 圖4及圖5分別顯示分光陣列36之底視圖及沿v_v線之 ，圖。分光陣列36包含具有不同光學性質之第一微透鏡7〇^及 第二微透鏡7〇b。第一微透鏡70a及第二微透鏡70b皆為平凸弋 因而具有正折射力(refractivepower)。然而，是不同的正折射力 參考圖5之截面圖的說明。 ’ 由此可知各微透鏡70a、70b具有讓從光束擴張單元32射 出之擴張光束34照到的平面入光面72,以及凸式曲形出光面 74。微透鏡70a、70b之入光面72設置在共同平面，但是第一 微透鏡70a及第二微透鏡70b具有不同的出光面74。更具體而 言，第一微透鏡70a之出光面74具有曲率半徑ra小於第二微透 鏡70b之出光面74的曲率半徑rb。於此實施例，曲率中心也$ 置在兩不同平面。於其他實施例，曲率中心可在相同平面類 15 201234120 似圖12另一實施例所示。 由圖、4之底視圖清楚可見，第一微透鏡7〇&及第二微透鏡 70b之出光面74具有相同面積的方形輪廓。於此實施例中，將 圖案決定成使得第-微透鏡7〇a及第二微透鏡勘交替，亦即 各第一微透鏡70a具有四個第二微透鏡7〇b作為鄰邊，反之亦 然。 於下’參考圖6說明包含不同微透鏡 70a、70b之分光陣列 =功能’其中圖ό為圖2之放大剪圖。僅顯示緊鄰在集光器52 前之光源30及平面76間的上部分照射系統12。 如上所述，從光束擴張單元32射出的擴張光束34至少實 質平行’亦即沒有發散或僅有小發散。當通過分光陣列36之第 一微透鎳70a及第二微透鏡70b之第一入光面72及被凸式曲形 出光面74折射時’因為第一微透鏡7〇a及第二微透鏡7〇b的正 折射力會被分成複數匯聚光東LB。 然而’由於第一微透鏡70a及第二微透鏡70b分別具有不 同的曲率半徑ra及fb，因此與第一微透鏡70a及第二微透鏡7〇b 關聯的光束會匯聚到不同程度。如圖6顯示分別從第一微透鏡 7〇a及第二微透鏡7〇b射出的兩道光束LBa及LBb。舉例而言， 因較強的匯聚光束LBa之焦點直接在相關微鏡42上，而較弱的 匯聚光束LBb之焦點遠在稜鏡46之出射面49附近，而使匯聚 性的不同變得更清楚。 201234120 ^不同的匯聚程度，或更正確地說光束LBa、LBb的不同發 政丨生^在第一聚光器5〇後之表面76的位置轉變成沿著X方向 ,不同光束直徑wa、Wb。從發散轉變成光束直徑是由第一聚光 器5〇達成，但若省略第一聚光器5〇則可在遠場觀察到。 因此，分光陣列36之第一微透鏡70a及第二微透鏡7〇b的 不同折射力在表面76產生光點，其依據光束直徑％、趴具有 不同的光點尺寸。 一般而言，根據以下式(1)，光點尺寸sp是依據微透鏡7〇a、 7〇b之節距p、它們的焦距fML及第一聚光器之焦距& : SP=p/fML *fc ⑴ 數學式描述顯示於圖6之效應，即第一微透鏡7〇a具有較 小的曲率半徑ra，因此較短的焦距fML在表面76產生較大的光 圖7顯不在表面76之例示輻照分布。較強匯聚光束LBa 所產生之較大光點以78a表示，而較弱匯聚光束LBb所產生之 較小光點以78b表示。光點78a、78b皆具有大約方形形狀，因 為苐微透鏡70a及第二微透鏡7〇b有方形輪廓。於此實施例， 將ra/rb比例選擇為使較小光點78b之尺寸大約為較大光點78& 之尺寸的四分之一。 舉例而言，若在表面70所需之輻照分布具有梯形幾何形 17 201234120 狀，如圖7之虛線80所示，此輻照分布可以兩種不同尺寸的光 點78a、78b來良好近似。 相較而言，圖8顯示若所有光點78具有相同尺寸而得到之 輻照分布，如習知所知者。相較於圖7所示之輻照分布，可知 所需梯形輻照分布80之近似明顯較不精確。 由於第一微透鏡7〇a及第二微透鏡70b之出射面74相等， 因此在較大光點78a及較小光點78b匯聚了相同量的光。因此， 較小光點78b之輻照度約為較大光點78a之輻照度的四倍大。 通常此為不利的效應。若第一微透鏡70a及第二微透鏡7〇b不 均勻的照射，則可避免此效應，藉此利用沒有光束均勻器就沒 有均勻輪廓的事實。因此，第一微透鏡及70a可設置成定位在 輻照度較高之雷射光束的中心，而第二微透鏡7〇b設置在輻照 度較低之周圍。 ^ 若可得到大量光點’則可藉由疊加大於一個(例如四個)較大 光點78a，來補償較大光點78a所產生之降低的輻照度。 於上述實施例中，藉由提供具有不同曲率之出射表面74的 第-微透鏡及7〇a及第二微透鏡7〇b，來達到光束服、⑽的 不同匯♦性。然而，亦可有其他方式來 ，而言，所有微透鏡7Ga、之出光面74可二二，但 = '有較小光學焦度之第二微透鏡赐可具有凹式曲形入光面 ,k替地所有微透鏡7〇a、7〇b之曲率可為相同但是第一 舉透鏡7〇a具有較大折射率，也造成增加的光學焦度。再次地， 201234120 =將，一微透鏡70a及第二微透鏡7〇b設置成圖4所示之交替 二利的。反而可重新分布使得例如—半的陣列僅由且有 =折射率之第—微透鏡7Ga所構成’而另—半僅由具交 射率之第二為透鏡70b所構成。 _ 自然亦可結合上述的手段。 再者，應瞭解第一微透鏡及70a及第二微透鏡70b的數目 =必相等，以及亦可有比兩種還多的不同類型微透鏡。舉例而 舌/若有光學焦度彼此不同的五種類型微透鏡，在表面76可能 曰得到五種不同的光點尺寸。如此通常提供更多的彈性來得到 所需的輻照分布。在類似於圖7及圖8之比較中，圖16及圖 顯示由三種不同光點尺寸之光點78a、78b、78c所得之例示輻 照分布（圖16)，以及僅有一種尺寸之光點78所得之輻照分布(圖 U)。顯然可知，三種光點尺寸比單一尺寸有較佳應照射圓形區 域80’之傳統照射設定的近似。 ^ IV. 分光陣列_節距變化 由式(1)清楚可知其他達到不同尺寸之光點的方法為改變分 列陣列36之微透鏡的節距p以及微透鏡之入光面及/或出光面之 面積。因此對所有微透鏡而言，微透鏡之折射力可能(但不—定 要)相同。 圖9及圖1〇為根據此類實施例之分光陣列136之底視圖及 201234120 =線x x之截面圖。再者，於此實施例中，微透鏡n、17〇b 為平凸微透鏡’各具有平面入光面172及凸式曲形出光面口4。 然而’於此實域中’對所有微透鏡口加、腿而言，出光面 皆相同。此乃藉由圖1〇中兩個具有相辭徑r之圓 形175來顯不。 鏡魏隱及第二微透 170a之出#® 174 /、有 更具體而言，第—微透鏡 的面、面積約比第二微透鏡17Gb之出光面174 距P=。 光面174不同的面積意味著微透鏡之節 雖然節距P改變，但是位在各 其對應= 光面=:=::=(= 廓。於所示實施例中，第-微透鏡170a之出不同的輪 邊形的輪廓，而第二微透鏡17〇b之出 具有正八 第-微透鏡17〇a及第二微透鏡17〇 4的輪靡為方形。 對在集光器52叙⑽輪廊 出光面174不同面積的效應顯示於 之投射系統12的剪圖，但分光陣列％ ，八為類似於圖6 列136所取代。再者，圖u 圖9及圖1〇之分光陣 …、射系統包含額外的光束均 20 201234120 勻器82,其改善在分光陣列136上由投射光以所產生之韓昭分 布的均勻性。光束均勾器82可組態為桿狀均勻器，或可包^光 學光柵元件之一或更多的陣列，如習知技術所知。 於圖11中，可知第一微透鏡170a及第二微透鏡17〇b所產 生之光束LBa及LBb分別於此實施例中也在表面76產生具有 不同直徑wa及wb之光點。此乃因光束LBa含有相對於光學軸 有較多傾斜之光線，而造成比光束LBb有更高的發散性之效 應。此較高的發散性轉變成在表面76有較大的光點尺寸。 圖11亦顯示第一微透鏡17〇a及第二微透鏡17%之焦距為 相等。於此，為簡明之故，將焦距選擇成使光束LBa、LBb聚 焦於反射鏡陣列40之微鏡42。於實際系統中，焦點通常位於其 他地方’以避免因為太高的輻照度而造成破壞微鏡42之反射塗 層0 V. 選替實施例 於圖9及圖10所示分光陣列136之實施例中，凸式曲形出 光面174之曲率中心不是在共同平面。因此，第一微透鏡n〇a 及第二微透鏡170b之焦距彼此些微的偏移。不論何種理由，若 不希望如此’可將分光陣列修改成如圖12所示。於此，第一微 透鏡170a及第二微透鏡n〇b之曲率中心位在共同平面，因此 第一微透鏡170a及第二微透鏡170b之焦平面完全相符。 21 201234120 ^於圖9及圖10所示實施例中，僅顯示兩種類型的不同尺寸 微透鏡。圖13及圖14以類似的底視圖及截面圖顯示出光面274 在統計上變化之分光陣列236之實施例。然而，微透鏡27〇之 頂點仍以週期性方式設置，如圖14之垂直虛線所示。若提供額 外的折射楔形體，則可不用此類頂點週期性設置。此類楔形體 可直接設置在微透鏡270上或在額外的支撐件上。 原則上微透鏡之出光面可能具有任何的任意形狀。圖15為 根據另一實施例之分光陣列330之底視圖，其中較小微透鏡之 出光面具有矩形、橢圓形、星形或三角形之形狀。其他較大微 透鏡具有不同的多邊形形狀。微透鏡之頂點於圖15中以小點卯 表示。 ‘ ，在不脫離本發明精神或必要特性的情況下，可以其他特定 形式來體縣發明。應將所述具體實施例各方©僅視為解說性 而非=制性。因此，本發明的範私隨附中請專利制所示而 非如前述說明卿。所有落在帽專郷圍之等效意義及範圍 内的變更應視為落在申請專利範圍的範疇内。 【圖式簡單說明】 本發明各種特徵及優點，結合伴隨圖式與詳細說明將更清 楚了解，其中： 圖1為根據本發明一實施例之投射曝光裝置之透視示意圖； 圖2為根據第一實施例之照射系統之截面圖，其中照射系 統為圖1之裝置中之部件； 圖3為於圖2所示之照射系統中所含之反射鏡陣列之透視 22 201234120 圖4為於圖2所示之照射系統中所含之分光陣列之上視圖; 圖5為圖4所示之陣列沿ν·ν線之截面圖； 圖6為圖3之放大剪圖，顯示分光陣列所產生的匯聚光束； 圖7,表面上有光束產生且有兩種不同尺寸之光點組合形 成所需例示輻照分布之表面的上視圖； 圖8為類似圖7之上視圖，但是其中光點全部具有相同尺 寸； 圖9為根據第一實施例之分光陣列之上視圖； 圖10為圖9所示之陣列沿χ·χ線之截面圖； 圖11為第二實施例類似圖ό之放大截面圖； 圖12為根據選替實施例類似圖10之截面圖； 圖13為根據第三實施例之分光陣列之上視圖； 圖Η為圖13所示之陣列沿χιν·χιν線之截面圖； 圖15為根據第四實施例之分光陣列之上視圖； /為表面上有光束產生且有三種不同尺寸之光點組合形 圓开^輻照分布之表面的上視圖；以及 圖 成所需 圖Η為類似圖16之上視圖，但是其中光點全部具有相同 【主要元件符號說明】 10 投射曝光裝置 照射糸統 場 光罩 圖案 縮小影像 12 14 16 18 18， 23 201234120 19 特徵 20 投影物鏡 21 透鏡 22 感光層 24 基板 29 殼體 30 光源 32 光束擴張單元 34 擴張光束 36 分光陣列 38 空間光調變器 40 陣列 42 微鏡 43 控制單元 45 系統控制器 46 稜鏡 48a、48b 表面 49 出射面 50 第一聚光器 52 集光器 54a ' 54b 光學光柵板 56 瞳平面 58 第二聚光器 60 場光闌平面 62 可調式場光闌 64 場光闌物鏡 66 光罩平面 24 201234120 70a 70b 72 74 76 78 78a、78b、78c 80 80, 82 90 136 170a ' 170b 172 174 175 236 270 274 336 A1 ' A2Then, in the far field or with an additional concentrator, the varying angular light is split into different spot sizes on the surface. For example, the light entering or exiting surface of one of the at least two optical elements may have a rectangular revenue' and the other of the at least two optical elements or the light exiting surface may have a human rim. For reasons of symmetry, people are smooth or light. 201234120 = The same round of training. However, there are various other types of optical spot sizes that can be used for different ages. The optical 7L piece can be placed on the sub-alignment towel, so that the light-emitting surface or the surface of the optical element is periodically set with the 'personal light of the rectangular outline'. The surface or the illuminating surface is alternately arranged with the illuminating surface or the illuminating surface of the octagon. Learned = f less than five optical components have different light -I have at least five different spot sizes. The production green = the day plus the light point group, the shot can contain the vehicle, its full _ splitting array and absorption, so that all the light into the two light loss, the projection _: = there = in the split light (four) no splitting array When entering the surface of the person, if the age is small, the uniform illumination of the light county is based only on the relevant light surface. This advantage is due to the position in the spot of the light generated by the specific beam. The material nature of the material, only the thief in the spectroscopic array <definition > light, the term "light" means any electromagnetic wheel, especially visible light, UV, DUV, 201234120 VUV and EUV light, and X-ray. The term "light" as used herein refers to light that can line describe the path of progress. The term "ray beam" as used herein refers to a plurality of rays having a common origin in the field plane. The term "beam" as used herein refers to light that passes through a particular lens or other optical element. The term "optical grating element" as used herein means that any optical element, such as a lens, iridium or diffractive optical element, is disposed with other optical grating elements to create or maintain a plurality of adjacent optical channels. The term "concentrator" as used herein refers to an optical system that increases the product of Α/^.α, where is the numerical aperture and α is the field area of the illumination. The term "concentrator" as used herein refers to the creation (at least approximately) of a Fourier (four) optical element or wire system between two planes, such as a field plane and a pupil plane. — The term “spatial irradiance distribution” as used herein refers to how the total irradiance changes over the actual or virtual surface illuminated. Usually the spatial irradiance distribution can be described by a function, where χ is less than the spatial coordinate of the point in the surface. If the field plane is used, (4) the touch distribution needs to be integrated to produce illuminance. The term "corner light distribution" as used herein means that the light illuminance of a light beam varies according to 10 201234120 degrees. Usually _distribution can be expressed as 八, 〃, α 〃 is the angular coordinate of the direction of the light. If the angle (4) knife cloth has field dependence, 4 is also the function of the field coordinate, that is, the term "surface" as used herein means that any surface in the three-dimensional space can be part of the object, or can be completely complete with the object. Separate, through the case of a plane or a plane. Field (4) "Optical Power" - The term indicates the ability of an optical component to have a diverging or converging effect on light. Therefore, the positive optical power has a divergent optical effect. % Negative / The "convergence effect" _ word used here means that g-aggregation increases regardless of whether the human shot S is divergent, flat, or concentrated. If the person's light is divergent, the hearing convergence must be added to the extent that the light beam emitted from the optical element is at least concentrated. The term "spot size" as used herein refers to the total area of a particular beam of light associated with a polarizing element that illuminates the surface. The measurement unit for the spot size is usually mm2. [Embodiment] General Structure of Projection Exposure Apparatus Fig. 1 is a very simplified perspective view of a projection exposure apparatus 1 according to the present invention, the projection exposure apparatus 10 including an illumination system 12 for generating a projection beam. Projection beam illumination 11 201234120 Example, Ϊ: field 14 on the mask 16 of the pattern and pattern 18. This embodiment has a ring segment shape which does not include the projection exposure device 10. However, other shapes of illumination fields 14, such as rectangles, are also contemplated. The projection objective 20 having the complex lens 21 images the pattern a in the illumination field 14 to the photosensitive layer 22 (e.g., photoresist) of the floor supported by the substrate 24. The substrate 24 can be formed by a = circle and is not placed on a wafer table (not shown) such that the top surface of the photosensitive layer is accurately positioned in the image plane of the projection objective 2 . The reticle 16 is positioned in the object plane of the projection objective 20 using a reticle stage (not shown). Since the projection objective lens 2 has a magnification β and is not < 1, the thumbnail 18 of the pattern 18 in the illumination field 14 is projected onto the photosensitive layer 22. During projection, the mask 16 and the substrate 24 are along the scanning direction. Move, the scanning direction is the same as the direction shown in Figure 1. The illumination field 14 then scans the light 16 to continuously image a patterned region that is larger than the illumination field 14. The speed ratio between the substrate and the reticle 16 is equal to the magnification of the projection objective lens 20. If the "projector 20 inverts the image (々< 〇), the light grass 16 and the substrate 24 move in the opposite direction, as indicated by arrows A1 and A2 in Fig. 1. However, the present invention can also be applied to a stepper tool in which the reticle 16 and the stencil 24 do not move during projection of the reticle. Figure II shows the screaming diagram of the illumination system 12 of Figure 1. The diagram of Figure 2 is not drawn to scale. In particular, it refers to only one or very few Optical element ^, * ' Γ \| > ρ ζ. 12 201234120 optical single 70. In fact, these units can contain significantly more lenses and other optical components. 30 will be two systems 12 including housing 29 and light source 30, that is, the light source of the embodiment is a pseudo-molecular laser. The light source 3 〇 emits a projection having a wavelength of about 193 nm, and other types of light sources are also considered, and other waves such as a tearing lung or 157 nm) sniper embodiment towel, The light beam emitted by the filament 3G enters the optical reading of the dilated beam. For this purpose, the beam expanding unit 32 may comprise, for example, a plurality of =Guang's mirrors. The divergent beam emitted from the beam juxta 32 is numbered % No, it has low divergence, that is, it is almost collimated. Beam 34 beam 34 enters the beam splitting array 36, and beam splitting _ 36 will expand the light = knife into a few converging beams LB. For the sake of simplicity, In Fig. 2, only the concentrated beam splitting _36 will be further in the next reference, and then the concentrated beam LB will advance. A variable spatial spoke H8 is produced in the pupil plane after the spatial light, and an array 4 for the micromirror 42 is included in the optical modulator 38. The micromirror = two spatially tilted about two orthogonal axes. H is connected to the overall system controller by means of the actuating element 43. The control chart is controlled by 43, and the control chart 3 is a perspective view of the array 40, how the light 1 is based on the light beam LB1 The micro-mirror gathers the beam (10) with a tilt angle and is reflected to different 201234120 directions. In Figures 2 and 3, the array 40 contains only 6-6 micro-mirrors 42. In fact, the array 40 can contain hundreds or even thousands. Micromirror 42. Referring to Figure 2, the spatial light modulator 38 further includes a crucible 46 having a first planar surface 48a and a second planar surface 48b, both of which are inclined relative to the optical axis OA of the illumination system 12. The surface 48a, 48b' beam LB is reflected by total internal reflection. The first surface 48a faces the beam LB reflected by the micromirror 42 of the micromirror array 4, and the second surface 48b directs the beam reflected by the mirror 42 The exit surface 49 of the crucible 46 is guided. Therefore, the direction of the light beam LB and the direction from the 稜鏡46 The angular irradiance distribution of the light exiting the exit surface 49 can be varied by individually tilting the micromirrors 42 of the array 40. For more details on the spatial light modulator 38, reference is for example made to US 2009/0115990 A1. The angular irradiance distribution produced by the transformer 38 is converted into a spatial irradiance distribution by means of a first concentrator 5 ' where the first concentrator 5 导引 directs the illumination beam LB towards the concentrator 52. In this embodiment The concentrator 52 includes two optical grating plates 54a, 54b, each containing two orthogonal arrays of cylindrical microlenses. The concentrator π produces a plurality of secondary sources in the subsequent pupil plane 56 of the illumination system 12. The second concentrating light 58 establishes a Fourier relationship between the pupil plane 56 and the field pupil plane 6〇, wherein the adjustable field stop 62 is disposed at the pupil plane 6〇. The second concentrator 58 superimposes the beam emitted from the secondary source into the field stop plane 6 , to illuminate the field stop plane 60 very uniformly. The % pupil objective lens 64 images the field stop plane 6〇 to the reticle plane 66, wherein the reticle 16 is disposed in the reticle plane 66 by means of a reticle stage (not shown). Furthermore, the adjustable soil pupil 62 is thereby imaged onto the reticle plane 66 and defines at least the short side of the illumination field μ 201234120 that extends along the scanning aspect γ. The irradiance distribution in front of the concentrator 52 determines the irradiance in the pupil plane 56 and thus determines the angular angle in the field pupil plane 60 and the reticle plane 66: The assist control unit 43 carefully sets the tilt of the mirror 42 of the mirror array 4 so that almost any arbitrary angular wheel = cloth can be produced on the mask plane 66. Thus, the angular irradiance distribution in the reticle plane 66 can be quickly matched to the pattern 18 contained in the reticle, f. With the optimized angular irradiance distribution, 18 can be imaged to the photosensitive layer 22 more accurately. I. III. Spectroscopic array - optical power change Figs. 4 and 5 respectively show a bottom view of the spectroscopic array 36 and a line along the v_v line. The spectroscopic array 36 includes a first microlens 7 and a second microlens 7〇b having different optical properties. The first microlens 70a and the second microlens 70b are both flat and convex and thus have a refractive power. However, it is a different positive refractive power with reference to the description of the sectional view of Fig. 5. Thus, it is understood that each of the microlenses 70a, 70b has a planar light incident surface 72 through which the expanded light beam 34 emitted from the light beam expanding unit 32 is irradiated, and a convex curved light exiting surface 74. The light incident surfaces 72 of the microlenses 70a, 70b are disposed on a common plane, but the first microlenses 70a and the second microlenses 70b have different light exiting surfaces 74. More specifically, the light exit surface 74 of the first microlens 70a has a radius of curvature ra smaller than the radius of curvature rb of the light exit surface 74 of the second microlens 70b. In this embodiment, the center of curvature is also placed in two different planes. In other embodiments, the center of curvature may be in the same plane class 15 201234120 as shown in another embodiment of FIG. As is clear from the bottom view of Fig. 4, the light exiting faces 74 of the first microlens 7& and the second microlens 70b have a square outline of the same area. In this embodiment, the pattern is determined such that the first microlens 7a and the second microlens are alternated, that is, each of the first microlenses 70a has four second microlenses 7〇b as adjacent sides, and vice versa. Of course. The spectroscopic array including the different microlenses 70a, 70b = function ' is shown below with reference to Fig. 6 which is an enlarged cut view of Fig. 2. Only the upper portion illumination system 12 between the light source 30 and the plane 76 immediately before the concentrator 52 is shown. As described above, the dilated beam 34 emerging from the beam expanding unit 32 is at least substantially parallel 'i.e., there is no divergence or only small divergence. When passing through the first light-incident surface 72 of the first micro-transparent nickel 70a and the second micro-lens 70b of the spectroscopic array 36 and being refracted by the convex curved light-emitting surface 74, 'because the first microlens 7a and the second microlens The positive refractive power of 7〇b will be divided into multiple convergent Guangdong LB. However, since the first microlens 70a and the second microlens 70b have different radii of curvature ra and fb, respectively, the light beams associated with the first microlens 70a and the second microlens 7bb converge to different degrees. As shown in Fig. 6, two light beams LBa and LBb which are emitted from the first microlens 7a and the second microlens 7b, respectively, are shown. For example, since the focus of the stronger concentrated beam LBa is directly on the associated micromirror 42, and the focus of the weaker concentrated beam LBb is farther near the exit surface 49 of the crucible 46, the difference in convergence becomes more clear. 201234120^Different degree of convergence, or more correctly different beam LBa, LBb, position of surface 76 after first concentrator 5 turns into X direction, different beam diameters wa, Wb . The transition from divergence to beam diameter is achieved by the first concentrator 5, but if the first concentrator 5 is omitted, it can be observed in the far field. Therefore, the different refractive powers of the first microlens 70a and the second microlens 7b of the spectroscopic array 36 produce spots on the surface 76 which have different spot sizes depending on the beam diameter %, 趴. In general, according to the following formula (1), the spot size sp is based on the pitch p of the microlenses 7〇a, 7〇b, their focal length fML, and the focal length of the first concentrator & : SP=p/ fML *fc (1) The mathematical expression is shown in the effect of Fig. 6, that is, the first microlens 7a has a smaller radius of curvature ra, so a shorter focal length fML produces a larger light on the surface 76. An example of an irradiance distribution. The larger spot produced by the stronger concentrated beam LBa is denoted by 78a, and the smaller spot produced by the weaker concentrated beam LBb is denoted by 78b. The spots 78a, 78b each have an approximately square shape because the pupil microlens 70a and the second microlens 7b have a square outline. In this embodiment, the ra/rb ratio is chosen such that the smaller spot 78b is approximately one-fourth the size of the larger spot 78& For example, if the desired irradiance distribution at surface 70 has a trapezoidal geometry 17201234120, as shown by dashed line 80 in Figure 7, this irradiance distribution can be well approximated by two different sized spots 78a, 78b. In comparison, Figure 8 shows the irradiance distribution obtained if all of the spots 78 have the same dimensions, as is known. Compared to the irradiance distribution shown in Figure 7, it is known that the approximation of the desired trapezoidal irradiance distribution 80 is significantly less accurate. Since the exit faces 74 of the first microlens 7a and the second microlens 70b are equal, the same amount of light is concentrated at the larger spot 78a and the smaller spot 78b. Therefore, the irradiance of the smaller spot 78b is approximately four times greater than the irradiance of the larger spot 78a. Usually this is an unfavorable effect. If the first microlens 70a and the second microlens 7b are unevenly illuminated, this effect can be avoided, thereby taking advantage of the fact that there is no uniform profile without the beam homogenizer. Therefore, the first microlens and 70a can be arranged to be positioned at the center of the laser beam having a higher irradiance, and the second microlens 7bb is disposed around the lower irradiance. ^ If a large number of spots are available, then the reduced irradiance produced by the larger spot 78a can be compensated by superimposing more than one (e.g., four) larger spots 78a. In the above embodiment, the different accommodities of the beam suits (10) are achieved by providing the first-microlenses and the 7 〇a and the second microlenses 7 〇b having the exit surfaces 74 having different curvatures. However, there may be other ways, for example, all of the microlenses 7Ga, the light exit surface 74 may be two or two, but = 'the second microlens with a smaller optical power may have a concave curved entrance surface, k The curvature of all the microlenses 7〇a, 7〇b may be the same but the first lens 7〇a has a larger refractive index, which also causes an increased optical power. Again, 201234120 = will, a microlens 70a and a second microlens 7b are set to alternate as shown in FIG. Instead, it can be redistributed such that, for example, the half-array consists of only the first microlens 7Ga having the refractive index and the other half is composed only of the lens 70b having the second conductivity. _ Naturally, it can also be combined with the above means. Furthermore, it should be understood that the number of first microlenses and 70a and second microlenses 70b must be equal, and there may be more than two different types of microlenses. For example, if the tongue/five types of microlenses with different optical powers are different from each other, five different spot sizes may be obtained on the surface 76. This usually provides more flexibility to achieve the desired irradiance distribution. In a comparison similar to Figures 7 and 8, Figure 16 and Figure show an exemplary irradiance distribution (Figure 16) obtained from three different spot size spots 78a, 78b, 78c, and a spot of only one size The resulting irradiance distribution (Fig. U). It will be apparent that the three spot sizes have a similar approximation to the conventional illumination setting that would illuminate the circular region 80' ^ IV. Spectroscopic array _ pitch variation It is clear from equation (1) that other methods of reaching different sized light spots are to change the pitch p of the microlenses of the column array 36 and the illuminating surface and/or the illuminating surface of the microlens. The area. Therefore, for all microlenses, the refractive power of the microlenses may be (but not necessarily) the same. 9 and 1B are bottom views of the beam splitting array 136 and a cross-sectional view of 201234120 = line x x according to such an embodiment. Furthermore, in this embodiment, the microlenses n, 17〇b are plano-convex microlenses ’ each having a planar light incident surface 172 and a convex curved light exit surface opening 4. However, in this real field, the illuminating surfaces are the same for all the microlens ports and legs. This is shown by the two circles 175 having the phase r in Figure 1 . Mirror Wei Yin and the second micro-transmission 170a out #® 174 /, more specifically, the surface of the first microlens, the area is about P = than the light-emitting surface 174 of the second microlens 17Gb. The different areas of the smooth surface 174 mean that the pitch of the microlens changes although the pitch P changes, but lies in its corresponding = smooth surface =:=::= (= profile. In the illustrated embodiment, the first-microlens 170a Different rounded contours are formed, and the rim of the second microlens 17〇b having the positive octa-microlens 17〇a and the second microlens 17〇4 is square. The pair is in the concentrator 52 (10) The effect of different areas of the façade 174 is shown in the cropping system of the projection system 12, but the spectroscopic array %, eight is replaced by a column 136 similar to Figure 6. Furthermore, Figure u Figure 9 and Figure 1 分 ... The beam system includes an additional beam of light 20 201234120, which improves the uniformity of the Hanzhao distribution produced by the projected light on the beam splitting array 136. The beam uniformizer 82 can be configured as a rod homogenizer, or An array of one or more optical grating elements can be included, as is known in the art. In FIG. 11, it can be seen that the light beams LBa and LBb generated by the first microlens 170a and the second microlens 17b are respectively In the embodiment, light spots having different diameters wa and wb are also produced on the surface 76. This is because the light beam LBa contains relative to the optical axis. There is more oblique light, resulting in a higher divergence effect than beam LBb. This higher divergence translates to a larger spot size at surface 76. Figure 11 also shows the first microlens 17〇 The focal lengths of a and the second microlens 17% are equal. Here, for the sake of brevity, the focal length is selected such that the light beams LBa, LBb are focused on the micromirror 42 of the mirror array 40. In practical systems, the focus is usually located in other Place 'to avoid damage to the reflective coating of the micromirror 42 due to too high irradiance. V. Alternative embodiment In the embodiment of the splitting array 136 shown in Figures 9 and 10, the convex curved exit surface 174 The center of curvature is not in a common plane. Therefore, the focal lengths of the first microlens n〇a and the second microlens 170b are slightly offset from each other. For any reason, if it is not desired, the spectroscopic array can be modified as shown in FIG. As shown here, the centers of curvature of the first microlens 170a and the second microlens n〇b are in a common plane, so that the focal planes of the first microlens 170a and the second microlens 170b are completely coincident. 21 201234120 ^图In the embodiment shown in FIG. 9 and FIG. 10, only two are displayed. Types of different sized microlenses. Figures 13 and 14 show an embodiment of a statistically varying spectroscopic array 236 of light surfaces 274 in a similar bottom and cross-sectional view. However, the vertices of the microlenses 27 are still arranged in a periodic manner. As shown by the vertical dashed line in Figure 14. If additional refractive wedges are provided, such vertices may not be periodically arranged. Such wedges may be placed directly on the microlens 270 or on additional supports. The light exit surface of the microlens may have any arbitrary shape. Fig. 15 is a bottom view of the light splitting array 330 according to another embodiment, wherein the light exiting surface of the smaller microlens has a rectangular, elliptical, star or triangular shape. Other larger microlenses have different polygonal shapes. The apex of the microlens is indicated by a small dot 图 in Fig. 15. ‘, the invention may be in other specific forms without departing from the spirit or essential characteristics of the invention. The specific embodiments of the specific embodiments are to be considered as illustrative only and not as a system. Therefore, the patent application of the present invention is shown in the patent system and is not as described above. All changes that fall within the equivalent meaning and scope of the cap will be considered to fall within the scope of the patent application. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic perspective view of a projection exposure apparatus according to an embodiment of the present invention; FIG. 2 is a first perspective view of the present invention; The cross-sectional view of the illumination system of the embodiment, wherein the illumination system is a component of the apparatus of FIG. 1; FIG. 3 is a perspective view of the mirror array 22 included in the illumination system shown in FIG. 2 201234120. FIG. Figure 5 is a cross-sectional view of the array shown in Figure 4 along the line ν·ν; Figure 6 is an enlarged view of Figure 3 showing the concentrated beam produced by the spectroscopic array Figure 7 is a top view of a surface having a beam of light generated and having two different sized spot combinations to form a surface of the desired irradiance distribution; Figure 8 is a top view similar to Figure 7, but with all of the spots having the same size Figure 9 is a top view of the spectroscopic array according to the first embodiment; Figure 10 is a cross-sectional view of the array shown in Figure 9 along the χ·χ line; Figure 11 is an enlarged cross-sectional view of the second embodiment; 12 is based on the alternative embodiment FIG. 13 is a top view of a light splitting array according to a third embodiment; FIG. 13 is a cross-sectional view of the array shown in FIG. 13 along a line χιν·χιν; FIG. 15 is a light splitting according to the fourth embodiment. Above view of the array; / top view of the surface of the irradiance distribution with light beam generated on the surface and having three different sizes of light spots; and the view of the desired image is similar to the top view of Figure 16, but The light spots are all the same [Main component symbol description] 10 Projection exposure device illumination system field mask pattern reduction image 12 14 16 18 18, 23 201234120 19 Feature 20 Projection objective lens 21 Lens 22 Photosensitive layer 24 Substrate 29 Housing 30 Light source 32 beam expansion unit 34 dilation beam 36 splitting array 38 spatial light modulator 40 array 42 micro mirror 43 control unit 45 system controller 46 稜鏡 48a, 48b surface 49 exit surface 50 first concentrator 52 concentrator 54a ' 54b optical grating plate 56 瞳 plane 58 second concentrator 60 field diaphragm plane 62 adjustable field diaphragm 64 field diaphragm objective lens 66 mask plane 24 201234120 70 a 70b 72 74 76 78 78a, 78b, 78c 80 80, 82 90 136 170a ' 170b 172 174 175 236 270 274 336 A1 ' A2
LB、LB 卜 LB2、LBa、LBb OA ra ' rb wa、wb 第一微透鏡 第二微透鏡 入光面 出光面 平面 光點 光點 輻照分布 圓形區域 光束均勻器 微透鏡之頂點 分光陣列 微透鏡 入光面 出光面 圓形 分光陣列 微透鏡 出光面 分光陣列 方向 匯聚光束 光學轴 曲率半徑 光束直徑 25LB, LB LB2, LBa, LBb OA ra ' rb wa, wb first microlens second microlens incident surface illuminating plane plane spot spot irradiance distribution circular region beam homogenizer microlens apex splitting array micro Lens entrance surface exit surface circular spectroscopic array microlens exit surface splitting array direction convergence beam optical axis curvature radius beam diameter 25