經濟部智慧財產局員工消費合作社印製 509979 五、發明說明（/ ) 本發明是有關一種底層抗反射層（Bottom Ant卜 Reflecdon Coatmg，BARC)的製造方法’且特別是有關一 種多層底層抗反射層（Multi-layer BARC)的製造方法。 在積體電路的集積度要求越來越高的情況下’整個電 路元件大小的設計也被迫往尺寸不停縮小的方向前進。而 整個半導體製程中最舉足輕重的可說是微影 (photolithography)製程’凡是與金氧半導體（Metal-Oxide-Semiconductor ; MOS)兀件結構相關的’例如：各層薄膜 的圖案（pattern) ’及慘有雜質（dopants)的區域’都是由微 影這個步驟來決定的。此外’整個半導體工業的元件積集 度，是否能繼續的往更小的線寬進行，也決定於微影製程 技術的發展。 在現今的微影技術中，曝光的光源波長已進展至 193nm的準分子雷射（excimer laser)，其可應用於0.13微 米甚或是〇·1微米的製程，所使用的光阻亦因應製程的進 步而改使用化學增幅型光阻（chemical enhance photo resist)，一般而言，爲了提升化學增幅型光阻的解析度及 形狀，而必須提高光阻的透光率，但是提高透光率的話， 在光阻層中的光由於沒有衰減，所以多重反射所造成的干 涉效應的影響會變得很大，另外曝光波長變短的話亦會使 多重干渉的影響變大，因此有必要在光阻與基板的界面覆 蓋底層抗反射層。 在目前的半導體製程中，無機材質的底層抗反射層通 常係採用氮化矽（SiN)或是氮氧化矽（si〇N)，然而，此些材 -------------裝— (請先閱讀背面之注意事項再填寫本頁) . -線_ 本紙張尺度適用中國國家標準（CNS)八1規格(:」川x、、釐） 509979 8095twf.doc/009 ‘ _B7 _ 五、發明說明（7/) 料在進行曝光後烤（Post Exposure Bake，PEB)的步驟時，請 (請先閱讀背面之注意事項再填寫本頁) 參照第1圖，由底層抗反射層102會釋放出例如是NH3的 鹼性物質106並進入光阻層104中，由於化學增幅型光阻 主要係由光酸108所組成，進入光阻層104中的鹼性物質 106會與光酸108中和而形成非活性化物質110。此非活 性化物質110的形成將會減少可反應光酸108的量，而使 得光阻層104的解析度降低。 有鑑於上述的缺點，本發明的目的在提出一種多層底 層抗反射層的製造方法，藉由在多層底層抗反射層上覆蓋 一層氧化層，而能夠防止鹼性物質進入光阻層中。而且， 覆蓋於多層底層抗反射層上的氧化層可以作爲多層底層抗 反射層的頂層，以增加多層底層抗反射層的應用範圍以及 彈性。 經濟部智慧財產局員工消費合作社印於 本發明提出一種多層底層抗反射層的製造方法，此方 法包括下列步驟：提供一個底材層，接著在底材層上形成 第一底層抗反射層，然後在第一底層抗反射層上形成第二 底層抗反射層，其後在第二底層抗反射層上形成氧化層， 再對氧化層進行電漿處理步驟，並由第一底層抗反射層、 第二底層抗反射層以及氧化層形成本發明之多層底層抗反 射層。其中多層底層抗反射層中的氧化層能夠防止第一、 二底層抗反射層的鹼性物質進入光阻層中。 爲讓本發明之上述目的、特徵、和優點能更明顯易懂， F文特舉一較佳實施例，並配合所附圖式，作詳細說明如 本紙济尺度·舍用中阀國家標丨f (CNS)A.l規格（210 χ297公楚） 509979 五、發明說明（3 ) 圖式之簡單說明： 第1圖所繪不爲習知底層抗反射層所產生的鹼性物質 進入光阻中，使光酸與鹼性物質酸鹼中和形成非活性化物 質的示意圖； 第2至4圖所繪示爲本發明較佳實施例之多層底層抗 反射層的製造方法的流程示意圖； 第5圖所繪示爲底層抗反射層的加熱溫度對鹼性物質 脫附曲線的示意圖；以及 第6圖所繪示爲單層及多層底部抗反射層的厚度誤差 於光阻和抗反射層界面的反射率變化圖。 圖式之標示說明： 100、200 :底材層 102 :底層抗反射層 104 :光阻層 106 :鹼性物質(NH3) 108 :光酸 110 :非活性化物質 202 :第一底層抗反射層 204 :第二底層抗反射層 206、210:氧化層 208、：電漿處理步驟 • 較佳實施例 第2圖至第4圖所繪示爲本發明較佳實施例之多層底 層抗反射層的製造方法的流程示意圖。 5 --------------裝--- (請先閱讀背面之注意事項再填寫本頁) . -·線Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 509979 V. Description of the Invention (/) The present invention relates to a method for manufacturing a bottom anti-reflective layer (Bottom Ant, Reflecdon Coatmg, BARC), and particularly to a multilayer bottom anti-reflective layer (Multi-layer BARC) manufacturing method. In the case that the integration degree of the integrated circuit is getting higher and higher, the design of the entire circuit element size is also forced to continue to shrink in size. The most important process in the entire semiconductor process can be said to be the photolithography process. 'Everything related to the metal-Oxide-Semiconductor (MOS) element structure.' For example: the pattern of each layer of thin film (pattern) and miserable The areas with dopants are determined by this step of lithography. In addition, whether or not the component accumulation of the entire semiconductor industry can continue to a smaller line width also depends on the development of lithography process technology. In today's lithography technology, the wavelength of the light source for exposure has progressed to 193nm excimer laser, which can be applied to processes of 0.13 microns or 0.1 micron. The photoresist used also depends on the process. Progress and use chemical enhance photo resist. In general, in order to improve the resolution and shape of the chemical increase photo resist, the transmittance of the photoresist must be increased, but if the transmittance is increased, Since the light in the photoresist layer is not attenuated, the interference effect caused by multiple reflections will become very large. In addition, if the exposure wavelength is shortened, the effect of multiple dryness will be increased. Therefore, it is necessary to The interface of the substrate covers the bottom anti-reflection layer. In the current semiconductor manufacturing process, the underlying anti-reflection layer of inorganic materials is usually silicon nitride (SiN) or silicon oxynitride (si〇N). However, these materials ----------- --Installation— (Please read the precautions on the back before filling this page). -Line_ This paper size is applicable to China National Standard (CNS) eight 1 specifications (: "Chuan x ,, centimeter) 509979 8095twf.doc / 009 ' _B7 _ V. Description of the invention (7 /) When performing the steps of Post Exposure Bake (PEB), please (please read the precautions on the back before filling this page) Refer to Figure 1 for anti-reflection from the bottom layer The layer 102 will release an alkaline substance 106 such as NH3 and enter the photoresist layer 104. Since the chemically amplified photoresist is mainly composed of photoacid 108, the alkaline substance 106 entering the photoresist layer 104 will interact with light. The acid 108 is neutralized to form an inactivated substance 110. The formation of this inactivated substance 110 will reduce the amount of reactive photoacid 108 and reduce the resolution of the photoresist layer 104. In view of the above disadvantages, the object of the present invention is to provide a method for manufacturing a multilayer bottom anti-reflection layer, which can prevent alkaline substances from entering the photoresist layer by covering an oxide layer on the multilayer bottom anti-reflection layer. Moreover, the oxide layer covering the multilayer bottom anti-reflection layer can be used as the top layer of the multilayer bottom anti-reflection layer to increase the application range and flexibility of the multilayer bottom anti-reflection layer. The consumer cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs printed in the present invention proposes a method for manufacturing a multi-layered anti-reflection layer. The method includes the following steps: providing a substrate layer, then forming a first underlying anti-reflection layer on the substrate layer, A second bottom anti-reflection layer is formed on the first bottom anti-reflection layer, and then an oxide layer is formed on the second bottom anti-reflection layer. The oxide layer is then subjected to a plasma treatment step, and the first bottom anti-reflection layer, the first The two bottom antireflection layers and the oxide layer form the multilayer bottom antireflection layer of the present invention. The oxide layer in the multilayer bottom anti-reflection layer can prevent alkaline substances of the first and second bottom anti-reflection layers from entering the photoresist layer. In order to make the above-mentioned objects, features, and advantages of the present invention more obvious and easy to understand, F Wen specifically mentions a preferred embodiment, and in conjunction with the accompanying drawings, will be described in detail such as this paper. f (CNS) Al specification (210 x 297) Chu 509979 V. Description of the invention (3) A brief description of the diagram: The alkaline substance produced by the conventional anti-reflection layer in the first layer is not drawn in the first picture, Schematic diagram of neutralizing photoacid and basic substance acid-base to form an inactive substance; Figures 2 to 4 are schematic flowcharts of a method for manufacturing a multi-layered bottom anti-reflection layer according to a preferred embodiment of the present invention; Figure 5 The schematic diagram shows the desorption curve of the basic anti-reflection layer against the temperature of the alkaline substance; and Figure 6 shows the thickness error of the single-layer and multi-layer bottom anti-reflection layer due to the reflection of the interface between the photoresist and the anti-reflection layer. Rate change graph. Description of the drawings: 100, 200: substrate layer 102: bottom anti-reflection layer 104: photoresist layer 106: alkaline substance (NH3) 108: photoacid 110: inactive substance 202: first bottom antireflection layer 204: Second underlying anti-reflection layer 206, 210: Oxidation layer 208 ,: Plasma processing steps • Preferred embodiments FIGS. 2 to 4 show the multilayered anti-reflection layer of the preferred embodiment of the present invention. Schematic diagram of the manufacturing method. 5 -------------- Install --- (Please read the precautions on the back before filling this page).
經齊郢智慧財4¾員工消費合作杜印S 本紙張尺度適用中國國家標準（CNS)A丨規格（210x297 ) 509979 Λ7 Π7 〇95twf.doc/009 五、發明說明（今） (請先閱讀背面之注意事項再填寫本頁) 首先，請參照第2圖，提供一個底材層200，此底材 層200例如爲基底、金屬層、多晶矽層、氮化矽層或氧化 矽層。接著，在底材層200上依序形成第一底層抗反射層 202以及第二底層抗反射層204。其中第一底層抗反射層 2〇2例如是氮氧化矽，形成的方法例如是以矽烷（SiH4)以 及一氧化二氮（N20)爲氣體源，以電漿增強型化學氣相沈 積法（Plasma Enhance Chemical Vapor Deposition，PECVD) 在底材層200上形成厚度爲20nm左右的薄膜。第二底層 抗反射層204例如是氮氧化矽，形成的方法如同上述形成 第一底層抗反射層202的方法，而在第一底層抗反射層202 上形成厚度爲20nm左右的薄膜。 ;線_ 接著，請參照第3圖，在第二底層抗反射層204上形 成氧化層206，其中形成氧化層206的方法例如是以四乙 基-鄰-矽酸酯（Tetraethylorthosilicate，TE0S)爲氣體源，以 電漿增強型化學氣相沈積法在第二底層抗反射層204上形 成氧化矽薄膜。 經濟部智慧財產局8工消費合作社印契 在上述的步驟中，氧化層206係由TE0S爲氣體源沈 積而成，由於此種TE0S氧化層的材質鬆軟，如欲隔絕底 下第二底層抗反射層204所釋出的鹼性物質進入光阻中， 所形成的氧化層必須有相當的厚度，然而對於整體的底層 抗反射層而言，厚度是有所限制的，因此，對於氧化層206 必須進行如後述的降低厚度以及密實化的處理，以使氧化 層206能夠以較薄的厚度阻擋鹼性物質。 接著，請參照第4圖，對氧化層206進行電漿處理步 本紙張尺嗖適用中阀國家標氓（CNSM1規格U]〇x297公楚） 509979 8095twf.doc/009 ^ _B7 _ 五、發明說明（< ) (請先閱讀背面之注意事項再填寫本頁) 驟208，以減少氧化層206的厚度需求以及密實化氧化層 206，經電槳處理後的氧化層206標示爲氧化層210，且第 一底層抗反射層202、第二底層抗反射層204以及氧化層 210所形成的堆疊層即爲本發明的多層底層抗反射層。其 中電漿處理步驟208所使用的例如是氧電漿、一氧化二氮 電漿或者是氧/ 一氧化二氮的混合電漿，經電漿處理後的 氧化層210的厚度爲15nm左右。 在上述製程所形成的多層底層抗反射層中，其消光係 數（extinction coefficient，亦即是吸收光線的能力）的大 小，由大至小依序爲第一底層抗反射層202大於第二底層 抗反射層204大於氧化層210。當光線透過光阻層射入多 層底層抗反射層時，層與層界面間的反射率能夠經由此種 堆疊的漸層構造而得以最小化，並且由下方的高反射材料 層（底材層）所反射上來的反射光亦能夠被一層一層的吸 收，因此，此種以不同消光係數以及反射率依序堆疊而成 的多層底層抗反射層，將能夠以一種的厚度適用於各種材 質的底材層上，而不須如同習知的單層底層抗反射層必須 因應底材層的不同而調整底層抗反射層的厚度。Through the cooperation of Wisdom Wealth 4¾ Employee Consumption Cooperation Du Yin S This paper size is applicable to Chinese National Standard (CNS) A 丨 Specifications (210x297) 509979 Λ7 Π7 〇95twf.doc / 009 V. Description of the Invention (Today) (Please read the Please fill in this page again.) First, please refer to Figure 2 to provide a substrate layer 200. This substrate layer 200 is, for example, a substrate, a metal layer, a polycrystalline silicon layer, a silicon nitride layer, or a silicon oxide layer. Next, a first underlying anti-reflection layer 202 and a second underlying anti-reflection layer 204 are sequentially formed on the substrate layer 200. The first bottom anti-reflection layer 202 is, for example, silicon oxynitride, and the formation method is, for example, using silane (SiH4) and nitrous oxide (N20) as gas sources, and plasma enhanced chemical vapor deposition (Plasma) Enhance Chemical Vapor Deposition (PECVD) forms a thin film with a thickness of about 20 nm on the substrate layer 200. The second underlying antireflection layer 204 is, for example, silicon oxynitride, and is formed in the same manner as the method for forming the first underlying antireflection layer 202 described above, and a thin film having a thickness of about 20 nm is formed on the first underlying antireflection layer 202. ; Line_ Next, referring to FIG. 3, an oxide layer 206 is formed on the second underlying anti-reflection layer 204. A method for forming the oxide layer 206 is, for example, tetraethyl-ortho-silicate (TEOS) as The gas source uses a plasma enhanced chemical vapor deposition method to form a silicon oxide film on the second underlying anti-reflection layer 204. In the above steps, the oxide layer 206 is deposited by TE0S as a gas source. Because the material of this TE0S oxide layer is soft, if you want to isolate the second bottom anti-reflection layer below The alkaline substance released by 204 enters the photoresist, and the oxide layer formed must have a considerable thickness. However, for the overall bottom anti-reflection layer, the thickness is limited. Therefore, the oxide layer 206 must be formed. As described later, the thickness is reduced and the densification is performed so that the oxide layer 206 can block the alkaline substance with a thin thickness. Next, please refer to FIG. 4 for plasma treatment of the oxide layer 206. The paper size is applicable to the national standard of the valve (CNSM1 specification U] 〇297297) 509979 8095twf.doc / 009 ^ _B7 _ 5. Description of the invention (≪) (Please read the precautions on the back before filling out this page) Step 208 to reduce the thickness of the oxide layer 206 and to compact the oxide layer 206. The oxide layer 206 after the electric paddle treatment is labeled as the oxide layer 210, The stacked layer formed by the first bottom anti-reflection layer 202, the second bottom anti-reflection layer 204, and the oxide layer 210 is the multilayer bottom anti-reflection layer of the present invention. The plasma treatment step 208 is, for example, an oxygen plasma, a nitrous oxide plasma, or a mixed plasma of oxygen / nitrogen monoxide. The thickness of the oxide layer 210 after the plasma treatment is about 15 nm. In the multilayer bottom anti-reflection layer formed by the above process, the size of the extinction coefficient (that is, the ability to absorb light) is in descending order of the first bottom anti-reflection layer 202 being greater than the second bottom anti-reflection layer. The reflective layer 204 is larger than the oxide layer 210. When light passes through the photoresist layer and enters the multi-layered bottom anti-reflection layer, the reflectivity between the layer-to-layer interface can be minimized through this layered layered structure, and the underlying layer of highly reflective material (substrate layer) The reflected light reflected can also be absorbed layer by layer. Therefore, this multilayer anti-reflection layer, which is sequentially stacked with different extinction coefficients and reflectances, can be applied to substrates of various materials with a thickness. On the layer, it is not necessary to adjust the thickness of the bottom anti-reflection layer according to the difference of the substrate layer as in the conventional single-layer bottom anti-reflection layer.
經濟部智慧財產局員工消費合作杜印K 接著，請參照第5圖，將本發明所形成的多層底層抗 反射層與未覆蓋氧化層的多層底層抗反射層進行加熱實 驗，其結果如第5圖所示，第5圖所示爲經氧電漿處裡過 的多層底層抗反射層（含氧化層）、經一氣化二氮電漿處裡 過的多層底層抗反射層（含氧化層）以及未經處理的多層底 層抗反射層（不含氧化層），由加熱至400°C對鹼性物質 7 本紙張尺嗖適用中國國家標準（CNS)Al規格（U〇x 3)7公釐） 509979 8095twf.doc/009 Λ/ ___ _C7_ 五、發明說明（b ) 釋放量的關係圖。一般而言，曝光後軟烤的溫度爲l〇〇°C 到l5〇°C左右，請參照第5圖中的100°C到150°c處，未經 處理的多層底層抗反射層其鹼性物質的釋放量明顯高出經 由電漿處理的其他兩者，由此可知，於底層抗反射層上覆 蓋氧化層，再經由電漿處理之後，能夠有效的阻絕鹼性物 質釋出。 接著，請參照第6圖，第6圖所示爲單層及多層底部 I 抗反射層的厚度誤差於光阻和抗反射層界面的反射率變化 圖，由第6圖中可知，單層底層抗反射層的厚度誤差對於 反射率的影響極大，尤其是在厚度誤差愈大時，反射率亦 隨之增大。另一方面，如同第6圖中所示的，對於多層底 層抗反射層而言，厚度誤差對於反射率的影響並不明顯， 因此多層底層抗反射層能夠適用於多種的底材層上。 更進一步的，請參照下列表1 : 表1 (請先閱讀背面之注意事項再填寫本頁) 訂. 底材層 多晶矽 鎢-砂 銅 鋁-矽 193nm的光學常 數（消光係數、反 射率） (0.90,2.30) (1.15,2.24) (0.96,1.37) (0.15,1.15) 來自光阻/底材層 的反射率、 51.2% 42.8% 27.2% 82.4% 來自光阻/底層抗 反射層/底材層的 反射率 0.569% 0.467% 0.916% 2.133% 線 木纸張尺嗳適用中阀阀家標爷（CNS)/\ 1規格（210 X 297公釐） 509979 〇95twf.doc/009 Λ； Π7 經濟部智慧財產局員工消費合作社印纪 五、發明說明（、） 表1所示爲在使用多晶矽、鎢-矽、銅、鋁-矽等四種 底材時，此四種材質在未形成多層底層抗反射層的反射 率’以及在底材層與光阻層之間設置本發明之多層底層抗 反射層的反射率。由表1可知，在未加入多層底層抗反射 層時，上述四種材質的光阻/底材層的反射率皆十分的大， 然而，在底材層與光阻層之間設置本發明之多層底層抗反 射層的反射率之後，其中所得的最大反射率爲鋁-矽材質， 僅爲2.133%，其餘的材質所得的反射率皆小於1%，因此， 本發明的多層底層抗反射層不僅適用於不同材質的底材 層，亦能夠有效的降低反射率。 在本發明的較佳實施例中，多層底層抗反射層的材質 • 係使用氮氧化矽，然而本發明並不限定於使用氮氧化矽， 亦可以使用氮化矽作爲多層底層抗反射層，並且能夠得到 與上述較佳實施例所述同樣的效果。 尙且，在本發明的較佳實施例中係形成TEOS氧化層， 再以電漿處理削減其厚度並使之密實化，然而氧化層的形 成方法並不限於此，亦可以使用高密度電漿化學氣相沈積 法（High Density Plasma Chemical Vapor Deposition, HDPCVD)，直接在多層底層抗反射層上形成具有適當厚度 以及緻密度的氧化層。 綜上所述，本發明的重要特徵係在多層底層抗反射層 上覆蓋一層氧化層，藉由氧化層而能夠防止多層底層抗反 射層中的鹼性物質進入光阻層中。 而且，本發明的多層底層抗反射層能夠以-種厚度應 9 ---------------- (請先閱讀背面之注意事項再填寫本頁) · |線· 本紙張义度適用中國國家標準（CNS)A l規格（210 X 1:*97公) ------ 509979 8095twf.doc/009 五、發明說明（$ ) 用於各種不同的底材層時，皆能夠使光阻層以及底材層的 反射率降至相當小的數値，因此能夠廣泛的應用於不同材 質的底材層，以及應用於不同材質的底材層形成於同一基 板的情形。 雖然本發明已以一較佳實施例揭露如上，然其並非用 以限定本發明，任何熟習此技藝者，在不脫離本發明之精 神和範圍內，當可作各種之更動與潤飾，因此本發明之保 護範圍當視後附之申請專利範圍所界定者爲準。 -------------J^·! (請先閱讀背面之注意事項再填寫本頁) 訂· —線· 經濟部智慧財產局員工消費合作社印製 ο 本纸張 <度適用中國國家標準（CNS)A丨規格（2丨()x的7公釐）Du Yin K, Consumer Cooperation of Employees, Bureau of Intellectual Property, Ministry of Economic Affairs Next, please refer to FIG. 5 for the heating experiment of the multilayer bottom anti-reflection layer formed by the present invention and the multilayer bottom anti-reflection layer not covered with the oxide layer. As shown in the figure, Figure 5 shows the multilayer anti-reflection layer (including the oxide layer) passing through the oxygen plasma, and the multilayer anti-reflection layer (including the oxide layer) passing through the gasified dinitrogen plasma. And untreated multilayer anti-reflective layer (excluding oxide layer), heated to 400 ° C for alkaline substances 7 This paper size is applicable to Chinese National Standard (CNS) Al specification (U〇x 3) 7 mm ) 509979 8095twf.doc / 009 Λ / ___ _C7_ 5. Explanation of the invention (b) The relationship diagram of the release amount. Generally speaking, the temperature of soft roasting after exposure is about 100 ° C to 150 ° C. Please refer to 100 ° C to 150 ° C in Figure 5. The release amount of sexual substances is significantly higher than that of the other two treated by the plasma. From this, it can be seen that the underlying anti-reflection layer is covered with an oxide layer and then treated by the plasma, which can effectively block the release of alkaline substances. Next, please refer to Fig. 6, which shows the change in thickness of the single-layer and multi-layer bottom I anti-reflection layer at the interface between the photoresist and the anti-reflection layer. From the figure, we can see that the single-layer bottom layer The thickness error of the anti-reflection layer has a great influence on the reflectance, and the larger the thickness error, the greater the reflectance. On the other hand, as shown in Fig. 6, for the multilayer anti-reflection layer, the influence of the thickness error on the reflectivity is not obvious, so the multilayer anti-reflection layer can be applied to a variety of substrate layers. Further, please refer to the following table 1: Table 1 (Please read the notes on the back before filling in this page) Order. Substrate layer polycrystalline silicon tungsten-sand copper aluminum-silicon 193nm optical constants (extinction coefficient, reflectance) ( 0.90, 2.30) (1.15, 2.24) (0.96, 1.37) (0.15, 1.15) reflectivity from photoresist / substrate layer, 51.2% 42.8% 27.2% 82.4% from photoresist / bottom antireflection layer / substrate layer The reflectivity of 0.569% 0.467% 0.916% 2.133% Wire wood paper ruler is applicable to the standard valve (CNS) / \ 1 specifications (210 X 297 mm) 509979 〇95twf.doc / 009 Λ; Π7 Ministry of Economic Affairs Intellectual Property Bureau Employee Consumer Cooperatives Yin Ji V. Invention Description (,) Table 1 shows the use of four substrates, such as polycrystalline silicon, tungsten-silicon, copper, aluminum-silicon, etc. The reflectivity of the reflective layer 'and the reflectance of the multilayer anti-reflection layer of the present invention provided between the substrate layer and the photoresist layer. It can be known from Table 1 that when the multilayer anti-reflection layer is not added, the reflectance of the photoresist / substrate layer of the above four materials is very large. However, the invention is provided between the substrate layer and the photoresist layer. After the reflectivity of the multilayer bottom anti-reflection layer, the maximum reflectance obtained therefrom is only 2.133%, and the reflectances of the other materials are less than 1%. Therefore, the multilayer bottom antireflection layer of the present invention not only Suitable for substrates of different materials, can also effectively reduce the reflectivity. In a preferred embodiment of the present invention, the material of the multilayer bottom anti-reflection layer is silicon oxynitride. However, the present invention is not limited to using silicon oxynitride, and silicon nitride can also be used as the multilayer bottom anti-reflection layer. The same effects as those described in the above preferred embodiment can be obtained. Moreover, in the preferred embodiment of the present invention, a TEOS oxide layer is formed, and then its thickness is reduced and densified by plasma treatment. However, the method for forming the oxide layer is not limited to this, and a high-density plasma may also be used. The chemical vapor deposition method (High Density Plasma Chemical Vapor Deposition, HDPCVD) directly forms an oxide layer having a proper thickness and density on a multilayer anti-reflection layer. In summary, an important feature of the present invention is that an oxide layer is overlaid on the multilayer anti-reflection layer. The oxide layer can prevent alkaline substances in the multilayer anti-reflection layer from entering the photoresist layer. Moreover, the multilayer anti-reflection layer of the present invention can be used in a thickness of 9 ---------------- (Please read the precautions on the back before filling this page) · | line · The meaning of this paper is applicable to Chinese National Standard (CNS) Al specifications (210 X 1: * 97 male) ------ 509979 8095twf.doc / 009 5. Description of the invention ($) It is used for various different substrate layers At the same time, the reflectance of the photoresist layer and the substrate layer can be reduced to a relatively small number. Therefore, it can be widely applied to substrate layers of different materials, and substrate layers of different materials formed on the same substrate. situation. Although the present invention has been disclosed as above with a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make various modifications and decorations without departing from the spirit and scope of the present invention. The scope of protection of the invention shall be determined by the scope of the attached patent application. ------------- J ^ ·! (Please read the notes on the back before filling out this page) Order · — Line · Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs ο This paper < Degree applies to China National Standard (CNS) A 丨 specifications (2 丨 (7mm of 7mm)