401599 經濟部中央標準局員工消費合作杜印製 A7 B7 五、發明説明（ 發明領域 本發明與微影製程有關，特— 、 真+ ;决汝I 種利用新的抗反 射層采改善微影圖案。 發明背景 .微型電路之製作需要對發基板上微小區 成元…： 雜區域亦須互相連接以形 用徜爭t!筠：± 〔或圖形之定義係利 用微影1程產生，當半導體元件 少妗眘女缽 项裡度知南’ VLSI電路 之·線寬亦隨之縮小。現今之半導401599 Consumption cooperation with employees of the Central Bureau of Standards, Ministry of Economic Affairs, Du printed A7 B7 V. Description of the invention (Field of the invention The present invention is related to the lithography process, special-, true +; ru ru I a new anti-reflection layer to improve the lithographic pattern Background of the Invention. The production of microcircuits requires the formation of micro-regions on the substrate ...: Miscellaneous regions must also be connected to each other to form a contention t! 筠: ± [or the definition of the pattern is generated by using lithography one pass, when the semiconductor The element width and width of the VLSI circuit are also reduced. The current semi-conductor
^ ^ ^ , 業疋朝向縮小VLSI « 、，但是内連線或其他如複晶矽、鋁' 矽化今 ： 微影製程之困難，因爲 化-材負的向反射性，將致使光阻曝光顯 "‘ 生典了避免<反射，進而造成光阻圖案變形。 產 這些問題於使用紫外光或深紫外光作爲微影 (曝光光源時’將更加嚴重。因爲於此波長範圍下基 學《物理特性，金屬之反射將增強，，經由光阻轉移之圖 更易被無法控制之底材反射所干擾。也因此於製作更先進 之積體電路，例如次微米積體電路時，其線寬將受到上， 影響而限制其發展。 述 發明目的及概诚： 本紙張尺度適用中國國家標準（CNS ) M規格（210X297公釐） (請先閲讀背面之注意事項再填窝本頁}^ ^ ^, The industry is shrinking VLSI «, but interconnects or other silicon such as polycrystalline silicon and aluminum 'silicidation today: the lithography process is difficult, because the negative retroreflectivity of the material will cause photoresist exposure " 'To avoid < reflection, which will cause deformation of the photoresist pattern. These problems are caused by the use of ultraviolet or deep ultraviolet light as lithography (when exposed to light sources, it will be more serious. In this wavelength range, the basic characteristics of "physical properties, the reflection of metals will be enhanced, and the maps transferred by photoresist will be more easily Interference caused by uncontrollable substrate reflection. Therefore, when making more advanced integrated circuits, such as sub-micron integrated circuits, its line width will be affected, which will limit its development. The purpose of this invention and its sincerity: This paper Dimensions are applicable to Chinese National Standard (CNS) M specifications (210X297 mm) (Please read the precautions on the back before filling in this page}
401599 A7 B7 五 發明説明（ 本發明之目的爲提供一種改善積體 ^ ^ ^ 货體電路導體層微 影圖案之方法。 、 基於上述目的，一種改善積體電路導體層微影圖索 爻方法被提出，此方法包括：沈積一氮氧化矽層於導電層 上’接著形成一氮化矽層於氮氧化矽層上，然後一光阻層 形成於氮化矽層之上，接下來以曝光波長小於44〇 nm ^ 電磁波將邵份之光阻曝光。 凰-式簡單説明： (請先閲讀背面之注意事項再填寫本頁) 經濟部中央標準局員工消費合作社印製 乐一a 屬或複 第一b 程之截 第二a 率對氧 第二b 對氮氧 第三a 率對氧 第三b 對氮氧 .圖爲本發明之形成雙層（dual-layer)結構於含有金 晶石夕化金屬底材上之截面圖； 圖爲描述本發明之底部抗反射層應用於DRAM製 面圖； 圖爲傳統方法中於曝光波長248 nm下，底材反射 化層厚度之數據圖； 圖爲本發明中於曝光波長248 nm下，底材反射率 化5夕層厚度之數據圖； 圖爲傳统方法中於曝光波長365 nm下，底材反射 化層厚度之數據圖；及 圖爲本發明中於曝光波長365 nm下，底材反射率 化石夕層厚度之數據圖。 訂 線 本紙張从適财關家榇準（CNS ) Α4· ( 21()><297公疫 401599 A7 _____B7______ 五、發明説明（） 發明詳細説明： 本發明所要揭示的爲一種改善積體電路導體層微 影圖案之方法。 第一 a圖顯示一種新的雙看（dual-layer)結構3，由 —氮化矽（SiN)14層與一氮氧化矽（Si〇xNy)層所組成。這 —·雙結構形成在金屬層（或是複晶矽化屬層）1 〇之頂部， 作爲底邵抗反射層（Bottom Anti-.Reflection Costing)。 第一 b圖描述本發明之底部抗反射層如何應用於 DRAM製程，其詳細步驟如下所述，一場氧化層4形成於 P型矽基板2上，一墊氧化層6被形成於矽基板露出之部 份上。接著沈積一複晶矽層8於墊氧化層6與場氧化層4 上，然後沈積一珍化鎢層1 0於複晶發層8上，隨後以電 漿增強式化學氣相沈積法沈積一氮氧化矽^⑴以“層12 於矽化鎢10之上，其厚度約爲150至1000埃，接著沈積 —氮化矽Μ於氮氧化矽（SiOxNy)層12上，厚度約爲1〇〇〇 至3000埃。 於此較佳實施例中，氮氧化矽（Si〇xNy)層12係作爲 —底部抗反射層（Bottom Anti-Reflection Coating)，用以 改善微影製程，氮化矽層14則作爲保護層及應力消除 層，光阻1 6則用作定義電晶體之閘極與字元線。 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） « in I · (請先閎讀背面之注意^項再填寫本頁) I ------ 經濟部中央標準局員工消費合作杜印製 401599 A7 B7 五、發明説明（ 經濟部中央標準局員工消費合作社印製 參考第二a圖，圖顯示傳統方法中以氮化發/氧化石夕 作爲底部抗反射層（Bottom Anti-Reflection Coating)，| 底材（複晶石夕化金屬或金屬）反射率對應氧化ί夕厚度之數 據圖。其中底材反射率是在曝光波長248nm下所量測， 如圖示，其底材反射率最少都有0.1以上。 參考第二b圖，圖顯示本發明中以氮氧化石夕 (Oxynitride)/氮化矽作爲底部抗反射層（Bottom Anti- Reflection Coating)，其底材（複晶矽化金屬或金屬）反射 率對應氮氧化矽（oxynitride)厚度之數據圖。其中底材反 射率是在曝光波長248 nm下所量測，底材（複晶珍化金屬 或金屬）之折射率爲1.97,吸收係數（extinction coefficient) 爲2.52。氮氧化珍（oxynitride)之折射率爲2.03，吸收係 數（extinction coefficient)爲 0.62 ;氮化矽之折射率爲 2.25，吸收係數（extinction coefficient)爲 0.0188。以最佳 實施例而言，氮氧化夕（oxynitride)之折射率之範圍爲 1.90 至 2.20’ 吸收係數（extinction coefficient)之範圍爲 0.45至0.65;氮化矽之折射率之範園爲ι·95至2_05，吸 收係數（extinction coefficient)之範圍爲 2.45 至 2.55。就 如圖示可以看出當氮氧化石夕（oxynitride)之厚度大約在40 nm時，底材（複晶矽化金屬或金屬）之反射率將接近於 零。 參考第三a圖，圖顯示傳統方法中以氮化矽/氧化矽作爲 底部抗反射層（Bottom Anti-Reflection Coating)，其底材 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公楚） (請先閲讀背面之注意事項再填寫本頁} Φ, 、-° 線' 經濟部中央標準局員工消費合作杜印製 401599 A7 __— _B7^___ 五、發明説明（） (複晶梦化金屬或金屬）反射率對應氧化砍厚度之數據 圖。其中底材反射率是在曝光波長365nm下所量測，如 圖示，其底材反射率最少都有0.20以上。 參考第三 b圖，圖顯示本發明中以氮氧化石夕 (oxynitride)/氮化矽作爲底部抗反射層（Bottom Ant“401599 A7 B7 Five invention descriptions (The purpose of the present invention is to provide a method for improving the lithography pattern of the cargo circuit conductor layer. Based on the above purpose, a method for improving the lithography pattern of the conductor circuit layer of the integrated circuit is improved. It is proposed that the method includes: depositing a silicon oxynitride layer on the conductive layer, then forming a silicon nitride layer on the silicon oxynitride layer, and then forming a photoresist layer on the silicon nitride layer, and then using an exposure wavelength Less than 44nm ^ Electromagnetic wave exposes Shao Fen's photoresist. Phoenix-style brief description: (Please read the precautions on the back before filling out this page) Printed by a consumer cooperative of the Central Standard Bureau of the Ministry of Economic Affairs The first a pass to the second a rate to oxygen, the second b to the nitrogen oxygen, the third a rate to the oxygen, the third b to the nitrogen and oxygen. The picture shows the formation of a dual-layer structure of the present invention A cross-sectional view on a metal substrate; The picture shows the bottom anti-reflection layer applied to the DRAM in the present invention; The picture shows the data of the thickness of the reflective layer of the substrate at the exposure wavelength of 248 nm in the traditional method; Invented in the exposure wavelength of 248 n Under the m, the substrate reflectivity data layer thickness data chart; the picture shows the traditional method of the substrate reflection layer thickness data at the exposure wavelength of 365 nm; and the picture shows the invention at the exposure wavelength of 365 nm ， The data chart of the thickness of the fossil layer of the substrate reflectance. The booklet of the booklet is from CNS Α4 · (21 () > < 297 public plague 401599 A7 _____B7______ 5. Description of the invention () Invention Detailed description: What is disclosed in the present invention is a method for improving the lithographic pattern of the integrated circuit conductor layer. Figure 1a shows a new dual-layer structure 3, which is composed of 14 layers of silicon nitride (SiN). And a silicon nitride oxide (SiOxNy) layer. This-double structure is formed on the top of the metal layer (or polysilicon silicide layer) 10, as a bottom anti-reflection layer (Bottom Anti-.Reflection Costing) Figure 1b describes how the bottom anti-reflection layer of the present invention is applied to the DRAM process. The detailed steps are as follows. A field oxide layer 4 is formed on the P-type silicon substrate 2 and a pad oxide layer 6 is formed on the silicon substrate. On the exposed part. Then deposit a polycrystalline silicon layer 8 on the pad An oxide layer 6 and a field oxide layer 4 are deposited, and then a refined tungsten layer 10 is deposited on the polycrystalline layer 8. Then, a silicon oxynitride is deposited by a plasma enhanced chemical vapor deposition method. On the tungsten silicide 10, the thickness is about 150 to 1000 angstroms, and then silicon nitride is deposited on the silicon oxynitride (SiOxNy) layer 12 and the thickness is about 1000 to 3000 angstroms. In this preferred embodiment In the middle, the silicon oxynitride (SiOxNy) layer 12 is used as a bottom anti-reflection coating (Bottom Anti-Reflection Coating) to improve the lithography process, and the silicon nitride layer 14 is used as a protective layer and a stress relief layer. 16 is used to define the gate and word line of the transistor. This paper size applies to China National Standard (CNS) A4 specification (210X297 mm) «in I · (Please read the notes on the back ^ before filling this page) I ------ Staff Consumption of the Central Bureau of Standards, Ministry of Economic Affairs Cooperative Du printed 401599 A7 B7 V. Description of the invention (printed by the Consumer Cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs and printed with reference to the second a picture, which shows the traditional method using nitrided hair / stone oxide as the bottom anti-reflection layer Reflection Coating), | Data chart of the reflectivity of the substrate (polycrystalline metal or metal) corresponding to the thickness of the oxide. The substrate reflectance is measured at the exposure wavelength of 248nm. As shown in the figure, its substrate The reflectivity is at least 0.1 or more. Referring to the second figure b, the figure shows that the present invention uses oxynitride / silicon nitride as the bottom anti-reflection coating (bottom anti-reflection coating). Data graph of silicidated metal or metal) reflectance corresponding to the thickness of silicon oxynitride. The substrate reflectance is measured at an exposure wavelength of 248 nm, and the refractive index of the substrate (polycrystalline metal or metal) is 1.97, absorption system (Extinction coefficient) is 2.52. The refractive index of oxynitride is 2.03, the absorption coefficient is 0.62; the refractive index of silicon nitride is 2.25, and the absorption coefficient is 0.0188. The best implementation For example, the range of the refractive index of oxynitride is 1.90 to 2.20 'and the range of the absorption coefficient is 0.45 to 0.65. The range of the refractive index of silicon nitride is ι · 95 to 2_05. The coefficient of coefficient (extinction coefficient) ranges from 2.45 to 2.55. As shown in the figure, when the thickness of oxynitride is about 40 nm, the reflectivity of the substrate (polycrystalline silicon silicide or metal) will be close to Refer to Figure 3a, which shows that in the traditional method, silicon nitride / silicon oxide is used as the bottom anti-reflection coating (Bottom Anti-Reflection Coating), and the paper size of the substrate is applicable to the Chinese National Standard (CNS) A4 specification ( 210X297 Gongchu) (Please read the precautions on the back before filling out this page} Φ, 、-° line 'Consumption cooperation between employees of the Central Standards Bureau of the Ministry of Economic Affairs 401599 A7 __— _B7 ^ ___ V. Description of the invention () (polycrystalline dream metal or metal) The data graph of the reflectance corresponding to the thickness of the oxide cut. The substrate reflectance is measured at the exposure wavelength of 365nm. As shown in the figure, the substrate reflectance is at least 0.20 or more. Referring to FIG. 3b, the figure shows that in the present invention, oxynitride / silicon nitride is used as the bottom anti-reflection layer (Bottom Ant "
Reflection Coating)，其底材（複晶矽化金屬或金屬）反射 率對應氮氧化石夕（oxynitride)厚度之數據圖。其中底材反 -射率是在曝光波長3 6 5 n m下所量測，底材（複晶夕化金屬 或金屬）之折射率爲2.92，吸收係數（extinction c〇efficient) 爲2.6。氮氧化石夕（oxynitride)之折射率爲2.05，吸收係數 (extinction coefficient)爲 0.6;氮化矽之折射率爲 2.05， 吸收係數（extinct ion coefficient)爲 〇.〇2。以最佳實施例 而言，氮氧化矽（oxynitride)之折射率之範園爲2.20至 3 ·0，吸收係數（extinction coefficient)之範圍爲 0.30 至 1_2 ;氮化矽之折射率之範圍爲1.95至2_15，吸收係數 (extinction co efficient)之範圍爲〇至〇.5。就如圖示可以 看出當氮氧化矽（oxynitride)之厚度大约在50 nm時，底 材（複晶梦化金屬或金屬）之反射率將接近於零。 由上述資料及數據顯示，本發明之氮氧化矽 (oxynitride)/氮化矽雙層（dual-layer)結構於微影波長小於 440 nm狀態下具有良好之抗反射功能。另外，値得一提 的是氮化矽與氮氧化矽（oxynitride)精確的厚度、折射 率·、與吸收係數均可由調整沈積製程參數而輕易控制。經 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） (請先閎讀背面之注意事項再填寫本頁)(Reflection Coating), a data chart of the reflectivity of the substrate (polycrystalline silicon silicide or metal) corresponding to the thickness of oxynitride. The reflectivity of the substrate is measured at an exposure wavelength of 3 65 nm. The refractive index of the substrate (polycrystalline metal or metal) is 2.92, and the absorption coefficient is 2.6. The refractive index of oxynitride is 2.05, and the absorption coefficient is 0.6; the refractive index of silicon nitride is 2.05, and the absorption coefficient is 0.02. In the preferred embodiment, the range of refractive index of silicon oxynitride is 2.20 to 3.0, the range of absorption coefficient is 0.30 to 1_2, and the range of refractive index of silicon nitride is 1.95. From 2 to 15, the absorption coefficient (extinction co efficient) ranges from 0 to 0.5. As shown in the figure, when the thickness of silicon oxynitride is about 50 nm, the reflectivity of the substrate (polycrystalline dream metal or metal) will be close to zero. According to the above data and data, the silicon oxynitride / silicon nitride dual-layer structure of the present invention has a good anti-reflection function when the lithography wavelength is less than 440 nm. In addition, it is mentioned that the precise thickness, refractive index, and absorption coefficient of silicon nitride and silicon oxynitride can be easily controlled by adjusting the deposition process parameters. The paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm) (Please read the precautions on the back before filling this page)
401599 A7 B7 五、發明説明（） 由此沈積參數之控制，我們即可得到最佳的氮氧化石夕 (oxynitride)之折射率、吸收係數、及厚度之範圍，以改 進微影製程之實行。更進一步，我們更可以於電漿蝕刻製 程中據以改善微影圖案之臨界尺寸。 本發明以較佳實施例説明如上，而熟悉此領域技藝 者，在不脱離本發明之精神範圍内，當可作些許更動潤 飾，其專利保護範圍更當視後附之申請專利範圍及其等同 領域而定。 (請先閱讀背面之注意事項再填寫本瓦) 經濟部中央標準局員工消費合作社印製 本紙張又度適用中國國家標準（CNS ) A4規格（210X297公釐）401599 A7 B7 5. Description of the invention () By controlling the deposition parameters, we can get the best range of refractive index, absorption coefficient, and thickness of oxynitride to improve the implementation of the lithography process. Furthermore, we can improve the critical size of the lithographic pattern in the plasma etching process. The present invention has been described above with reference to the preferred embodiments, and those skilled in the art can make some modifications and modifications without departing from the spirit of the present invention. Equivalent field depends. (Please read the notes on the back before filling in this tile.) Printed by the Consumer Cooperatives of the Central Bureau of Standards of the Ministry of Economic Affairs This paper is again applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm)