TW200401952A - Attenuated embedded phase shift photomask blanks - Google Patents

Attenuated embedded phase shift photomask blanks Download PDF

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TW200401952A
TW200401952A TW92108395A TW92108395A TW200401952A TW 200401952 A TW200401952 A TW 200401952A TW 92108395 A TW92108395 A TW 92108395A TW 92108395 A TW92108395 A TW 92108395A TW 200401952 A TW200401952 A TW 200401952A
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phase shift
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TWI245167B (en
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Marie Angelopoulos
Katherina Babich
S Jay Chey
Michael Straight Hibbs
Robert N Lang
Pravin Mahorowala Arpan
Christopher Racette Kenneth
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Ibm
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Priority claimed from US10/122,876 external-priority patent/US6682860B2/en
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Abstract

An attenuating embedded phase shift photomask blank that produces a phase shift of the transmitted light is formed with an optically translucent film made of metal, silicon, nitrogen and oxygen. An etch stop layer is added to improve the etch selectivity of the phase shifting layer. A wide range of optical transmission (0.001% up to 15% at 157 nm) is obtained by this process.

Description

200401952 玖、發明說明: 相關專利申請案之交叉參照 2001年2月26曰申請且同在申請中之美國專利申請案第 09/793,646號,其標題為「衰減嵌入相移光罩空位」,該案 之内容以引用方式併入本文中。 發明所屬之技術領域 本發明係針對衰減嵌入相移光罩空位,具體而言,係針 對衰減相移光罩(APSM)材料及其加工製程。 先前技術 由於相移光罩能夠產生高於傳統二元光罩的解析度之 圖像,其作為第二代微電子製造微影蝕刻技術正愈來愈引 起吾人之關注。於多種相移設計方案中,由Burn J.Lin於「固 態技術」(Solid State Technology, January issue,page 43(1992))提出之衰減嵌入相移器正獲得廣泛接受,其原因 在於其製作容易且節省費用,該文之内容以引用方式併入 本文中。為改進光罩之光學屬性(即,光透射之可調諧性及 對光子輻照和化學處理之阻抗性),目前已有多個與該設計 方案相關之變化形式。 專業人士現將157 nm微影蝕刻認作一繼193 nm之後之微 影蝕刻方案。且前尚無適於157 nm並顯現出適宜之光學屬 性、可調諧性、輻照及化學耐久性、蝕刻選擇性、低瑕疵 且製造便利之成熟APSM材料。先前,於2001年2月26曰申 請之美國專利申請案第〇9/793,646號中,吾人曾揭示了一 種基於SiTiN,SiTiON系統(用於193 nm微影蝕刻技術)之 84782 doc 200401952 APSM材料及其加工製程,該案之内容以引用方式併入本 文中。 藉由本文’吾人旨在說明材料之組合、157 nm APSM材 料(具體而言,一種疊置雙層結構)之製作方法及一種相移 光罩之製作方法,該種光罩具有可調諧之光透射且在使用 (光子輻照及化學處理)中結合了穩定之光學屬性及一優良 之蝕刻選擇性。該組合物由帶有一蝕刻阻擋層之SiMx〇yNz 材料組成’其中,兀素M代表_巾請專利範圍中所述之金 屬。 發明内玄: 、本發明之一廣闊方面包括一種衰減嵌入相移光罩空 位其犯夠在一選擇之微影蝕刻波長下產生一具有至少 o.oom光透射之18〇。相移,且具有化學/光學耐久性及靈活 的光透射可調諧性。 、本發明之另一方面包括一種製作一衰減嵌入相移光罩 之製程’該製程包括—雙層薄膜相移材料之沉積步驟。 本發月之另方面包括一相移物質組合物,其包括一相 移層及一姓刻阻擋層。 實施方式 本發明之物質組合物及製程係用於製作光罩空位,其可 製成具有下列性能之相移薄膜:可調諧之光學特性(%τ、η 及kXT為光透射;η為折射率;k為消光係數);在157麵波 長下之1 8 0 °相移;良好的pό 、 夕艮好的抗雷射輻照及化學處理之穩定 性;及良好的蝕刻選擇性。該相移薄膜包含—雙層結構。 84782 -7- 200401952 毗鄰基板之層控制著%丁且亦作為一蝕刻阻擋層,而其頂部 疊置層乃相移層。第一層包含一金屬或金屬基薄膜。下文 中提出一欽和备實例。相移薄膜包含碎、一金屬、氮及/ 或氧。該金屬可為一來自第π族、第…族、第v族、過渡金 屬、鑭系兀素及婀系元素之元素。下文中提出一鈦當做該 金屬之實例。本發明包括位於一蝕刻阻擋層上之相移層 (SlwTlxNyOz,其中w介於〇」〜〇 6之間,χ介於〇 〇1〜〇二之 間y 於〇〜〇·6之間,Ζ介於0〜0.7之間)、一沉積於一基 板(石英氟化石英、CaF2或八丨2〇3等)上之蝕刻阻擋層(金屬 或金屬基層)及該相移層及蝕刻阻擋層之形成方法。 1、沉積 薄膜可藉由濺射沉積方法(RF、DC磁控管、AC磁控管、 脈衝又極DC磁控f、RF二極體濺射、或熟悉此項技術者 所熟知之其他濺射沉積方法)自一由一種組合材料(例如: Τ-χΜχ,其中,x介於〇·〇1〜0.5之間,Μ代表一來自第„族、 罘IV族、第V族、過渡金屬、鑭系元素及婀系元素之任一 群、、且4兀素)製成之單一目標或由不同組合物製成之兩個 或兩個以上目標(例如:SiO2及Μ目標或SikMx及Μ目標) 况和而成。組合目標之組合變化或純粹目標之功率及沉積 寺間之單獨變化皆可導致薄膜之組合變化。對於單一目 土板夾持0可為固定式或可為繞軌道轉動,而對於多 目^基板夾持台須繞軌道轉動且轉速可調。 具體而Τ,對於相移層siTi〇(鈦當做元素μ)之單一目標 (Sl〇7(TlSl2)01)沉積採用了 RF磁控管濺射沉積,而餘刻阻 ί52?δ 84782 doc 200401952 擋層(Ta&amp;Ti)之沉積採用了 dc磁控管沉積。為獲得具有良 好抗化學處理(用於光罩清洗)穩定性之薄膜,沉積條件需 最佳化。吾人業已判明耐化學性所需之較佳沉積條件。 2、 光學屬性 相移層及蝕刻阻擋層之光學屬性(折射率(n)及消光係數 (k))皆藉由一量程為mo nm至700 nm之多角度vesa Woollam橢圓偏振計測定。爾後,藉由使用該等光學常數 來計算出用以獲得一 18〇。相移之較佳薄膜厚度。在橢圓偏 振計之透射模式下量測18〇。相移時之透射,並且比較所計 算出之透射值。藉由監視雷射輻照ApS]V^^品時之雷射強 度變化,即時監視雷射輻照期間之透射變化。雷射量測裝 置與Liberman等人所述〇999)裝置相同。 3、 實例 (八)3^1^&amp;02單一層 1)處理氣體Αγ/〇2/Ν2 將基板置於一繞軌道轉動之旋轉夾具或定位於一非繞 軌道轉動之目標下,使用一 Sl。7(TlSl2)Q】目標沉積由 SlwTlxNyOz構成之薄膜。在一具有丨〇 mT Ar分壓之氬/氮/ 氧混合氣體中實施濺射。Ar、乂及A均採用超高純度之氣 體(99·999%)且沉積室之背景壓力為&lt;9·〇χΐο、ΟΓΓ。薄膜藉 由RF磁控管濺射方法用 所 一5英寸直徑之目標沉積而成 用功率為450 W。上述條件下,沉積率通常為〇 3至丨6入〆 秒0 錢射前 目標以450 W功率在5 mT氬氣内 受到5分鐘之預 G2?9 84782 doc 200401952 賤射;爾後’再在薄膜之沉積條件下受到5分鐘之預濺射, 藉以預處理縯目標之表面。預藏射後,基板較佳立即藉由 一裝載鎖定室(load lock chamber)裝入沉積室且立即實施 沉積。依據沉積條件,薄膜厚度介於4〇〇〜2〇〇〇A之間。圖 2將光透射顯示為波長之一函數。該薄膜之折射率k為21〇 且吸收常數k為0.467。該薄膜之對應厚度745A,其在157 nm 波長時之光透射為5·26%。根據計算,若需在157 nm波長 下獲得一 180。相移以致成一 5.9%之透射,具有相同光常數 之薄膜舄要一 711人之厚度。藉由調整氧:氮之比率,在157 nm波長下可達成高達18〇/〇之透射。圖3為各種具有不同氧 :辰度(藉由X射線光電子能譖方法及盧瑟福(Rutherford)背 散射方法測得)之薄膜之原子組合列表。光學常數η及k藉由 VESA Woollam橢圓偏振計量測且同時算出對應於18〇。相 移之薄膜厚度在157 nm波長下之光透射。隨氧濃度之增 大,折射率η降低。因此,180。相移所需薄膜厚度與157nm 波長下之光透射一同增大。 雖然此單一層APSM可滿足光學屬性之要求,但石英之 姓刻選擇性卻不佳,CP*電漿下之蝕刻選擇性不足〗·7。上 述狀況之原因在於下列事實:若欲獲得合適之光透射,需 要相當高之氧濃度(&gt;35%),而此等高氧濃度卻導致石英基 板之低擇性。作為一改進姓刻選擇性之努力,吾人發明 了 一採用一蝕刻阻擋層之雙層APSM。 (B)SiwTix〇z/金屬雙層 對於雙層APSM而言,一金屬蝕刻阻擋層沉積於氟化石 02〇0 84782 doc -10 - 200401952 英基板之上(圖l)。在本文中,吾人所示實例為鈥蝕刻阻擋 層及姮蝕刻阻擋層。沉積金屬蝕刻阻擋層之後,使用一 Si〇 7(TiSi2)〇 !目標沉積一由SiwTixNy〇z構成之相移層。本文 所舉實例使用了在Si至Ti之約定比率下具有最大透明度 (y=〇)之組合物。 金屬層之濺射在具有1.0 mT Αι*分壓之氬處理氣體中實 施,其方式為DC磁控管濺射。在實際薄膜沉積前,目標受 到10分鐘之預濺射,同時基板被隔離於裝載鎖定室内。薄 膜以介於150〜300 W之功率用一 5英寸直徑之目標沉積而 成。在上述條件下,沉積率通常為2·3至4·5Α/秒。通常, 姓刻阻擋層之厚度介於ΐ〇Α〜400Α之間。金屬姓刻阻擋層 沉積完畢後,基板轉移至裝載鎖定室且同時進行相移層之 預賤射清洗。該相移層藉由RF濺射沉積用一 5英寸直徑目 標沉積而成。以此為例,一 siTl〇薄膜在具有〗〇 mT ^分 壓(1 5 seem時之Ar流量)之氬/氧混合處理氣體下沉積而 成。氧氣藉由一 Gransville-Phillips精確洩漏閥泄入,以保 持一介於0.10〜〇.7〇mi^g之恒定〇2分壓。rf射頻範圍從 450 W至900 W。在前述條件下,沉積速率通常為〇75至 1.7A/秒。依據沉積條件之不同,相移層之厚度介於4〇〇〜 2000A之間不等。 下列適於相移層siTi〇之條件下曾達成最佳光學及化學 耐久性。RF功率設置為900 W,Ar分壓為1.0 mT且氧分壓 為〇·55 mT。僻使薄膜之氧分壓低於0.35 mT,因薄膜之氧 氣納入里過低’其光透射過低而不具有實際使用價值。另 84782 doc -11 - 200401952 外,低沉積功率(450 W)導致了低劣之化學耐久性,其原因 可旎在於薄膜之高孔隙度(低密度)。裝載基板之前,使用 一氧氣灰化器來預清洗基板,以清除會在157 nm波長下降 低光透射之碳氫化合物。 圖4所不為作為波長函數之SiTi〇/Ti及SiTiO/Ta光透射曲 、’泉對於兩種APSM,檢驗波長248 nm下之光透射皆低於 3〇%,此乃另一勝過單層aPSm之優點。相移層SlTl〇之原 子組合展示於圖3列表中。光學常數(n*k)及薄膜厚度係藉 由WooUam橢圓偏振計所量測。圖5在列出上述數值之同時 亦列出對應於157 nm波長之光透射。雙層設計方案之優點 在於·與單層相比,其光透射更易於調整。僅藉由調整蝕 刻層而無需改變氧氣濃度即可調整光透射。舉例而言,厚 度為1150人(其中鈦厚度為149人)之siTi〇薄膜可獲得一光 透射為5.9。/〇之180。相移。若將鈦降至60人(且义1^〇降至 1175A) ’光透射即變為12%。同樣,厚度為117〇人之义丁 i〇 薄膜(其中赵厚度為106A)可獲得一光透射為5 9%之18〇。相 移。若將妲降至50A(且SiTi〇降至1183A),光透射變為 10.6% 〇 圖6概括了相移層SiTiOi %T在1 57 nm波長下之變化,該 變化為硫酸/過氧化氫清洗溶液旧23〇4:112〇2=3:1,9〇。(:)中 浸沒時間之函數;該溶液亦稱之為piranha溶液,通常在製 造線中用於移除光阻。在長達丨丨5分鐘之浸沒中,〇/〇ΊΓ之總 變化為0.3%。該卓越之穩定性可保證該材料與標準光罩製 迻方法之相容性。為對比起見,圖中亦示出了低功率(45〇 w) 84782 doc •12- 200401952 沉積之情形。該雙層SiTi〇/Ta之化學耐久性亦顯示出極穩 定之%丁(作為piranha清洗一函數)。圖7概括了雙層SiTi〇/Ta 之%丁在157 nm波長下之變化,該變化乃硫酸及過氧化氫清 洗溶液中浸沒時間之函數。最初清洗後,T%自6.07%增至 6.27%,隨後,長達90分鐘之清洗僅使T%增大0.02%。此 一結果表明雙層SiTi〇/Ta具有耐受反復清洗之極佳化學穩 定性。 圖8概括了單層設計方案與雙層設計方案之蝕刻選擇 性。SiTiO/Ti與SiTiO/Ta可相互媲美,兩者皆係單層設計方 案之重大改良。然而,在相同之蝕刻條件下,鈦/石英組合 較艇/石英組合顯現出更佳之餘刻選擇性。200401952 发明 Description of the invention: Cross-reference to related patent applications refers to U.S. Patent Application No. 09 / 793,646, filed on February 26, 2001, and is also pending. The contents of the case are incorporated herein by reference. FIELD OF THE INVENTION The present invention is directed to the attenuation of the phase-shift mask vacancy, specifically, to the material of the attenuation phase-shift mask (APSM) and its manufacturing process. Prior art Because phase shift masks can produce images with higher resolution than traditional binary masks, they are attracting more and more attention as the second-generation microelectronics manufacturing lithography etching technology. Among various phase-shift design schemes, the attenuation embedded phase shifter proposed by Burn J. Lin in "Solid State Technology" (Solid State Technology, January issue, page 43 (1992)) is gaining wide acceptance due to its easy fabrication And save money, the content of this article is incorporated herein by reference. In order to improve the optical properties of the reticle (that is, the tunability of light transmission and the resistance to photon irradiation and chemical treatment), there have been many variations related to this design scheme. Professionals now consider 157 nm lithography as a lithography solution after 193 nm. And there is no mature APSM material suitable for 157 nm and showing suitable optical properties, tunability, irradiation and chemical durability, etch selectivity, low defects, and convenient manufacturing. Previously, in US Patent Application No. 09 / 793,646 filed on February 26, 2001, we have disclosed a 84782 doc 200401952 APSM material based on the SiTiN, SiTiON system (for 193 nm lithography technology) and For the manufacturing process, the content of the case is incorporated herein by reference. Through this article, we aim to explain the combination of materials, the manufacturing method of 157 nm APSM material (specifically, a stacked double-layer structure) and the manufacturing method of a phase shift mask, which has a tunable light Transmission and in use (photon irradiation and chemical treatment) combine stable optical properties and an excellent etch selectivity. The composition is composed of a SiMxOyNz material with an etch barrier layer, wherein the element M represents the metal described in the patent claims. Inventive Mystery: A broad aspect of the present invention includes an attenuated embedded phase shift reticle vacancy which is sufficient to produce a light transmission with a light transmission of at least 0.oom at a selected lithographic etching wavelength. Phase shifted with chemical / optical durability and flexible light transmission tunability. 2. Another aspect of the present invention includes a process for making an attenuated embedded phase shift mask. The process includes a step of depositing a two-layer thin film phase shift material. Another aspect of the present month includes a phase shifting material composition including a phase shifting layer and an inscription blocking layer. Embodiments The substance composition and manufacturing process of the present invention are used to make a mask vacancy, which can be made into a phase-shifting film having the following properties: tunable optical characteristics (% τ, η, and kXT are light transmission; η is a refractive index ; K is the extinction coefficient); 180 ° phase shift at a wavelength of 157 planes; good resistance to laser irradiation and chemical treatment; good etching selectivity. The phase-shifting film includes a two-layer structure. 84782 -7- 200401952 The layer adjacent to the substrate controls% D and also acts as an etch stop layer, and the superimposed layer on top of it is a phase shift layer. The first layer includes a metal or metal-based film. An example is given below. The phase-shifting film contains debris, a metal, nitrogen, and / or oxygen. The metal may be an element from group π, group ..., group v, transition metal, lanthanide and actinide. An example of the metal is given hereinafter. The present invention includes a phase shift layer (SlwTlxNyOz) on an etch barrier layer, where w is between 0 ″ ~ 〇6, χ is between 0.001 ~ 〇2, y is between 0 ~ 0.6, Z (Between 0 ~ 0.7), an etch stop layer (metal or metal base layer) deposited on a substrate (quartz, fluorinated quartz, CaF2 or VIII, etc.) and the phase shift layer and the etch stop layer Formation method. 1. The deposited film can be deposited by sputtering (RF, DC magnetron, AC magnetron, pulsed DC magnetron f, RF diode sputtering, or other sputtering known to those skilled in the art) The method of radio-deposition is based on a combination of materials (for example: Τ-χΜχ, where x is between 0.001 ~ 0.5, and M represents a group of metals from Group VII, Group IV, Group V, Transition metal, Any group of lanthanides and actinides, and 4 elements) or a single target made of different compositions or two or more targets (for example: SiO2 and M targets or SikMx and M targets) The combination changes of the combined target or the pure power of the target and the separate changes between the deposition temples can lead to the combined change of the film. For a single mesh soil plate clamping, 0 can be fixed or can be rotated around the track, and For multi-head ^ substrate clamping table must be rotated around the track and the speed can be adjusted. Specifically, for the single target (S107 (TlSl2) 01) of the phase shift layer siTi0 (titanium as the element μ) is deposited using RF magnetic Controlled sputtering deposition, while resisting 52? Δ 84782 doc 200401952 barrier (Ta & Ti) The deposition uses dc magnetron deposition. In order to obtain a thin film with good chemical resistance (for photomask cleaning), the deposition conditions need to be optimized. We have determined the best deposition conditions required for chemical resistance. 2 Optical properties The optical properties (refractive index (n) and extinction coefficient (k)) of the phase shift layer and the etch stop layer are measured by a multi-angle vasa Woollam ellipsometry with a range from mo nm to 700 nm. By using these optical constants to calculate the best film thickness to obtain a phase shift of 180. Measure 18 ° in the transmission mode of an ellipsometry. Transmission at the phase shift and compare the calculated transmission Value. By monitoring the change in laser intensity when laser irradiating ApS] V ^^, the transmission change during laser irradiation is monitored in real time. The laser measurement device is the same as the device described by Liberman et al. 3. Example (8) 3 ^ 1 ^ & 02 single layer 1) Processing gas Aγ / 〇2 / Ν2 Place the substrate in a rotating fixture orbiting or non-orbiting target, use a Sl.7 (TlSl2) Q] The target deposit is composed of SlwTlxNyOz Into a thin film. Sputtering is performed in an argon / nitrogen / oxygen mixed gas with a partial pressure of 〇mT Ar. Ar, krypton, and A are all ultra-high purity gases (99.999%) and the background pressure of the deposition chamber <9 · 〇χΐο, ΟΓΓ. The film was deposited by a RF magnetron sputtering method with a 5-inch diameter target with a power of 450 W. Under the above conditions, the deposition rate is usually 0 to 6 Into the leap second, the target was pre-sprayed with 450 W power in 5 mT argon for 5 minutes before G2? 9 84782 doc 200401952, and then shot again; and then under 5 minutes of pre-sputtering under the film deposition conditions. Pre-process the surface of the target. After the pre-hatch, the substrate is preferably immediately loaded into the deposition chamber through a load lock chamber and deposited immediately. According to the deposition conditions, the thickness of the film is between 400 and 2000A. Figure 2 shows light transmission as a function of wavelength. The film had a refractive index k of 21 ° and an absorption constant k of 0.467. The corresponding thickness of this film is 745A, and its light transmission at a wavelength of 157 nm is 5.26%. According to calculations, a 180 is obtained at a wavelength of 157 nm. The phase shift is such that a transmission of 5.9%, and a film with the same optical constant, requires a thickness of 711 persons. By adjusting the oxygen: nitrogen ratio, a transmission of up to 18/0 can be achieved at a wavelength of 157 nm. Figure 3 is a list of the atomic combinations of various films with different oxygen: Chen degrees (measured by the X-ray photoelectron energy method and Rutherford back-scattering method). The optical constants η and k were measured by VESA Woollam ellipsometry and calculated simultaneously to correspond to 18 °. Phase-shifted film thickness transmits light at a wavelength of 157 nm. As the oxygen concentration increases, the refractive index η decreases. So 180. The film thickness required for phase shifting increases with the transmission of light at a wavelength of 157nm. Although this single-layer APSM can meet the requirements of optical properties, the selectivity of quartz is poor, and the etching selectivity under CP * plasma is insufficient. The reason for the above situation lies in the fact that, in order to obtain proper light transmission, a relatively high oxygen concentration (&gt; 35%) is required, and these high oxygen concentrations result in the low selectivity of the quartz substrate. As an effort to improve the selectivity of the last name, we invented a double-layer APSM using an etch barrier. (B) SiwTixOz / metal double layer For the double-layer APSM, a metal etch stopper is deposited on the fluorite 2200 84782 doc -10-200401952 substrate (Figure 1). In this article, we show examples of “etch stop layer” and “etch stop layer”. After depositing the metal etch stop layer, a Si07 (TiSi2) target is used to deposit a phase shift layer composed of SiwTixNyz. The examples given herein use compositions with maximum transparency (y = 0) at the agreed ratio of Si to Ti. The sputtering of the metal layer was performed in an argon processing gas having a partial pressure of 1.0 mT A ** by means of DC magnetron sputtering. Before the actual thin film deposition, the target was subjected to a pre-sputter for 10 minutes, while the substrate was isolated in the load lock chamber. The film was deposited with a target of 5 inches in diameter at a power between 150 and 300 W. Under the above conditions, the deposition rate is usually from 2.3 to 4.5 A / sec. Generally, the thickness of the barrier layer is between ΐ〇Α ~ 400Α. After the metal barrier layer is deposited, the substrate is transferred to the load lock chamber and the pre-emission cleaning of the phase shift layer is performed at the same time. The phase shift layer was deposited by RF sputter deposition with a 5 inch diameter target. Taking this as an example, a siT10 thin film was deposited under an argon / oxygen mixed processing gas having a partial pressure (Ar flow rate at 15 seem) of 0 mT ^. Oxygen was leaked through a Gransville-Phillips precision leak valve to maintain a constant partial pressure of 0.10 to 0.7 mig. The rf radio frequency range is from 450 W to 900 W. Under the aforementioned conditions, the deposition rate is usually from 0 75 to 1.7 A / second. Depending on the deposition conditions, the thickness of the phase shift layer ranges from 400 to 2000A. Optimum optical and chemical durability has been achieved under the following conditions suitable for the phase shift layer siTi0. The RF power was set to 900 W, the Ar partial pressure was 1.0 mT, and the oxygen partial pressure was 0.55 mT. The oxygen partial pressure of the film is lower than 0.35 mT. Because the oxygen of the film is too low, the light transmission is too low and it has no practical value. In addition to 84782 doc -11-200401952, the low deposition power (450 W) results in poor chemical durability, which can be attributed to the high porosity (low density) of the film. Prior to loading the substrate, an oxygen asher was used to pre-clean the substrate to remove hydrocarbons that would have low light transmission at 157 nm. Figure 4 does not show the light transmission curves of SiTi0 / Ti and SiTiO / Ta as a function of wavelength. For both types of APSM, the light transmission at the inspection wavelength of 248 nm is less than 30%, which is another advantage over the single. Advantages of layer aPSm. The atomic combinations of the phase shift layers SlT10 are shown in the list of FIG. The optical constant (n * k) and film thickness are measured by a WooUam ellipsometer. Figure 5 lists the above values as well as the light transmission corresponding to a wavelength of 157 nm. The advantage of the two-layer design is that its light transmission is easier to adjust than a single layer. The light transmission can be adjusted only by adjusting the etching layer without changing the oxygen concentration. For example, a siTi0 film with a thickness of 1150 people (of which 149 is titanium) can obtain a light transmission of 5.9. / 〇 之 180. Phase shift. If the titanium is reduced to 60 persons (and it is reduced to 1175A), the light transmission becomes 12%. Similarly, a thin film of Yiding Io with a thickness of 117 (in which Zhao has a thickness of 106A) can obtain a light transmission of 59% to 18%. Phase shift. If 妲 is reduced to 50A (and SiTi〇 is reduced to 1183A), the light transmission becomes 10.6%. Figure 6 summarizes the change of the phase shift layer SiTiOi% T at a wavelength of 1 57 nm. The solution was 2403: 112〇2 = 3: 1,90. (:) as a function of immersion time; this solution is also known as the piranha solution and is commonly used in manufacturing lines to remove photoresist. During a 5-minute immersion, the total change of 0 / 〇ΊΓ was 0.3%. This excellent stability guarantees compatibility of the material with standard photomask transfer methods. For comparison, the figure also shows the case of low power (45w) 84782 doc • 12- 200401952 deposition. The chemical durability of the double-layered SiTi0 / Ta also showed extremely stable% tin (as a function of piranha cleaning). Figure 7 summarizes the change in the double-layer SiTi0 / Ta at 157 nm as a function of immersion time in sulfuric acid and hydrogen peroxide cleaning solutions. After the initial cleaning, the T% increased from 6.07% to 6.27%, and then, the 90% cleaning only increased the T% by 0.02%. This result indicates that the double-layered SiTi0 / Ta has excellent chemical stability withstanding repeated cleaning. Figure 8 summarizes the etching selectivity of the single-layer design and the double-layer design. SiTiO / Ti and SiTiO / Ta are comparable to each other, both of which are major improvements in the single-layer design. However, under the same etching conditions, the titanium / quartz combination shows better after-hour selectivity than the boat / quartz combination.

SiTi〇/Ta與SiTi〇/Ti皆顯現出耐受157 nm雷射輻照之極 佳穩定性。圖9概括了在157 nm波長下SiTi〇/Ti APSMi%T 之變化,該變化乃157 nm雷射輻照(使用Lambda Physik LPX 120 F2雷射)之一函數。在50 Hz頻率下使用到雷射功 率密度為2.5 mJ/平方公釐/脈衝之雷射輻照該薄膜。5.0 kJ/ 平方公釐劑量下之總光透射變化為0.50%。在一氧氣低於2 ppm之氮氣環境中輻照樣品。SiTiO/Ti APSM之總增量為 0.5%(自5.94%增至6.44%)。同樣,81丁1〇/丁&amp;雙層試驗可與 SiTi〇/Ti雙層相媲美。圖10概括了 3丨丁丨〇/丁&amp;之%丁在157 11111 波長下之變化,該變化乃157 nm雷射轉照(使用Lambda Physik LPX 120雷射)之一函數。在50 Hz頻率下使用雷射 功率密度為2.5 mJ/平方公釐/脈衝之雷射輻照薄膜。5.0 kJ/ 平方公釐劑量下之總光透射變化為0.5 5%。在一氧氣低於2 02B3 84782 doc - 13 - 200401952 PPm炙氮氣環境中輻照樣品。siTi〇/Ta之總增量為〇 “%(自 5.71%增至 6·26%)。 雖然本文使用若干本發明之實施例來說明本發明,但本 又並非意欲將本發明限於上述說明,而僅將其限於後附申 凊專利範園所述之範疇。所要求擁有專屬所有權或特權之 本發明實施例在隨附申請專利範圍内界定。本文中所引用 &lt;全邯參考資料之内容均以引用方式併入本文中。 遷式簡單說明 結合附圖閱讀並熟思上述詳細說明及本發明本身,本發 明 &lt; 該些及其它目的、特點及優點清晰可見,圖式中: 圖1所示為APSM之單層方法及雙層方法示意圖。 圖2所示為單一層方法(具體而言,SiTiON)作為波長之函 數之光透射曲線圖。 圖3為在1 57 nm波長下產生1 80。相移及相應光透射所 需之原子組合、光學常數n*k及厚度之列表。原子組合藉 由X射線光電子能暗方法及盧瑟福(Rutherford)背散射方法 里測。光學常數藉由W〇〇llain橢圓偏振計量測。厚度和光 透射利用光學常數算出。 圖4以波長之函數顯示雙層apsm之光透射曲線圖。(a) 頂層為相移層siTi〇,而底層為蝕刻阻擋層Ti。(b)頂層為 相移層SiTiO,而底層為姓刻阻擒層Ta。 圖5顯不157 nm波長下之光學常數…和k)、薄膜之厚度及 相應之光透射。光學常數藉由VESA Woollam橢圓偏振計量 測,而180°相移及光透射之對應厚度利用光學常數算出。 84782 doc 200401952 圖6為光透射與相移層SiTiO在一 90°C熱硫酸/過氧化氫 (H2S〇4 : H2〇2 = 3 : 1)混合液中清洗時間之曲線圖。 圖7為一光透射與雙層SiTi〇/Ta在一 90°C熱硫酸/過氧化 氫(H2S〇4 : H2〇2 = 3 : 1)混合液中清洗時間之曲線圖。 圖8為一帶有對應蝕刻氣體之SiTiO、Ti、Ta及石英RIE 蝕刻選擇性列表。 圖9為APSMSiTiO/Ti之雷射耐久性曲線圖。光透射變化 繪製為雷射劑量之一函數。157 nm雷射光束之能量密度為 2.5 mJ/平方公釐/脈衝,且重複率為50 Hz。總雷射劑量為5 kJ/平方公釐。 圖10為APSM SiTi〇/Ta之雷射耐久性曲線圖。光透射變 化續製為雷射劑量之一函數。1 5 7 nm雷射光束之能量密度 為2.5 mJ/平方公釐/脈衝,且重複率為50 Hz。總雷射劑量 為5 mJ/平方公釐。 84782 doc -15 -Both SiTi〇 / Ta and SiTi〇 / Ti show excellent stability against 157 nm laser radiation. Figure 9 summarizes the change in SiTi0 / Ti APSMi% T at a wavelength of 157 nm, which is a function of 157 nm laser irradiation (using Lambda Physik LPX 120 F2 laser). The film was irradiated with a laser power density of 2.5 mJ / mm² / pulse at a frequency of 50 Hz. The total light transmission change at a dose of 5.0 kJ / mm2 was 0.50%. Irradiate the sample in a nitrogen atmosphere with oxygen below 2 ppm. The total increase in SiTiO / Ti APSM was 0.5% (from 5.94% to 6.44%). Similarly, the 81d10 / d &amp; double-layer test is comparable to the SiTi0 / Ti double-layer test. Figure 10 summarizes the change of 3%, 3%, 3%, 3%, and 3% at a wavelength of 157 to 11111, which is a function of the 157 nm laser radiation (using Lambda Physik LPX 120 laser). The film was irradiated with a laser power density of 2.5 mJ / mm² / pulse at a frequency of 50 Hz. The total light transmission change at a dose of 5.0 kJ / mm2 was 0.5 5%. The samples were irradiated in an oxygen atmosphere below 2 02B3 84782 doc-13-200401952 PPm nitrogen. The total increase of siTi0 / Ta is 0% (increased from 5.71% to 6.26%). Although this invention uses several examples of the invention to illustrate the invention, this is not intended to limit the invention to the above description, It is only limited to the scope described in the attached Shenyang Patent Fanyuan. The embodiments of the present invention that require exclusive ownership or privileges are defined within the scope of the accompanying patent application. The contents of the "Quanhan References" cited herein Both are incorporated herein by reference. The simple description of the transfer type is read in conjunction with the drawings and considered the above detailed description and the present invention itself. These and other objects, features, and advantages of the present invention are clearly visible in the figure: Figure 1 Shown is a schematic diagram of the single-layer method and the double-layer method of APSM. Figure 2 shows the light transmission curve of the single-layer method (specifically, SiTiON) as a function of wavelength. Figure 3 shows the generation of 1 80 at a wavelength of 1 57 nm. List of atomic combinations, optical constants n * k, and thicknesses required for phase shift and corresponding light transmission. Atomic combinations are measured by the X-ray photoelectron dark method and Rutherford back scattering method. The optical constants are determined by W〇llain ellipsometry measurement. Thickness and light transmission are calculated using optical constants. Figure 4 shows the light transmission curve of the double-layer apsm as a function of wavelength. (A) The top layer is the phase shift layer siTi〇, and the bottom layer is the etch barrier. Ti. (B) The top layer is the phase shift layer SiTiO, and the bottom layer is the etch-blocking layer Ta. Figure 5 shows the optical constants at 157 nm wavelength ... and k), the thickness of the film and the corresponding light transmission. Optical constants Based on VESA Woollam ellipsometry measurement, the corresponding thickness of 180 ° phase shift and light transmission is calculated using optical constants. 84782 doc 200401952 Figure 6 shows the light transmission and phase shift layer of SiTiO at 90 ° C hot sulfuric acid / hydrogen peroxide. (H2S〇4: H2〇2 = 3: 1) Curve of cleaning time in the mixed solution. Figure 7 is a light transmission and double-layer SiTi〇 / Ta at 90 ° C hot sulfuric acid / hydrogen peroxide (H2S〇4 : H2〇2 = 3: 1) The cleaning time curve in the mixed solution. Figure 8 is a list of SiTiO, Ti, Ta and quartz RIE etching selectivity with corresponding etching gas. Figure 9 is the laser durability of APSMSiTiO / Ti Graph of light transmission. The change in light transmission is plotted as a function of laser dose. The density is 2.5 mJ / mm² / pulse, and the repetition rate is 50 Hz. The total laser dose is 5 kJ / mm². Figure 10 shows the laser durability curve of APSM SiTi〇 / Ta. The change in light transmission The continuation is a function of the laser dose. The energy density of a 15 7 nm laser beam is 2.5 mJ / mm² / pulse and the repetition rate is 50 Hz. The total laser dose is 5 mJ / mm². 84782 doc -15-

Claims (1)

200401952 拾、申請專利範圍: 1. -種運用在微影㈣之衰減相移光罩空位,其包括: 一基板; 一沉積於該基板上之蝕刻阻擋層; 一沉積於該蝕刻阻擋層上之相移層;及 该相移光罩芝位可在&lt;500 11111選擇波長下產生一基本 上具有180。相移且至少0.001%光透射之光罩。 2. 如申請專利範圍第丨項之衰減相移光罩空位,其中該相移 層包括一具有公式AwBxNy〇z之組合材料,其中A係一選 自由第WA族、帛VA族或第VIA族所組成之群、组;⑽選 自由-來自第Π族、第口族、第w、過渡金屬、鋼系元 素和婀系元素之元素所組成之群組;其中w介於約〇1〜 約0.6之間,X介於約0.01〜約〇·2之間,y介於約〇〜約〇.6 之間,z介於約0〜約0.7之間。 3_如申請專利範圍第丨項之衰減相移光罩空位,其中該相移 層包含一矽/鈦/氮/氧組合物。 4.如申請專利範圍第3項之衰減相移光罩空位,其中該矽/ 鈦/氮/氧組合物具有結構式siwTixNy〇z,其中w介於約〇1 〜約0.6之間,X介於約0.01〜約〇 2之間,y介於約〇〜約 〇·6之間,z介於約〇〜約〇·7之間。 5·如申請專利範圍第1項之衰減相移光罩,其中該相移層具 有一介於約400A〜約2000A間之厚度。 6·如申請專利範圍第1項之衰減相移光罩,其中該蝕刻阻擋 層包含一選自由一金屬所組成之群組的材料或一組合材 m 84782 doc _ ι . 200401952 料,其中該組合材料包含一選自由—金屬所組成之群組 的材料、-來自第π族、第IV族和第%之元素、氮和氧。 7. 如申請專利範圍第6項之衰減相移光罩,其中該钱刻阻播 層包含一選自由鈦和妲所組成之群組的材料。 田 8. 如申請專利範圍第6項之衰減相移光罩,其中該姓刻阻擔 層具有一介於約50人〜約500A間之厚度。 9. 如申請專利範圍第1項之衰減相移光罩,其中該相移層為 SiTiO,該蝕刻阻擋層為鉦(Ta)。 10·如申請專利範圍第1項之衰減相移光罩,其中該相移層為 SiTiO,該蝕刻阻擋層為鈦(Ti)。 11 · 一種微影蝕刻用衰減相移光罩空位之製作方法,其包括: 提供一基板; 在該基板上設置一钱刻阻播薄層; 在該基板上設置一相移層; 該空位能夠在一 &lt;500 nm之選擇波長下產生一具有 1 80。相移及至少0.001%光透射之光罩。 12 ·如申請專利範圍第11項之方法,其中該相移層包括一具 有公式AwBxNyOz之組合材料,其中a係一選自由第IVA 族、第VA族或第VIA族所組成之群組;b係選自由一來自 第Π族、第IV族、第V族、過渡金屬、鑭系元素和婀系元 素之元素所組成之群組;其中w介於約0.1〜約〇 6之間, X介於約0.01〜約0.2之間,y介於約〇〜約0 6之間,z介於 約0〜約0.7之間。 1 3 ·如申請專利範圍第11項之方法,其中該相移層包含一選 S2S; 84782 doc -2 · 200401952 自由一矽/鈦/氮組合物與一矽/鈦/氮/氧組合物所組成之 群組的材料。 14·如申請專利範圍第丨丨項之方法,其中該矽/鈦/氮/氧組合 物具有結構式SiwTixNyOz,其中w介於約0· 1〜約〇 6之 間,X介於約0.01〜約〇·2之間,y介於約〇〜約〇6之間,z 介於約0〜約0 · 7之間。 1 5 ·如申請專利範圍第1丨項之方法,其中該相移薄膜係藉由 使用一技術從兩個或兩個以上不同組合物目標濺射沉積 所形成,該技術係選自由RF匹配網路、DC磁控管、AC 磁控管、脈衝雙極DC磁控管及RF二極體所組成之群組。 16.如申請專利範圍第15項之方法,其中該相移層係藉由使 用一方法從一組合材料(Sil-xTix)目標濺射沉積所形成, 其中X介於約0.01〜約〇.5之間,該方法係選自由RF匹配 網路、DC磁控管、AC磁控管、脈衝雙極DC磁控管及RF 二極體所組成之群組。 1 7 ·如申請專利範圍第1 5項之方法,其中該基板被設置於一 夾具内’該夾具可繞軌道轉動或固定式,及/或旋轉或不 旋轉。 18.如申請專利範圍第11項之方法,其中該相移薄膜係藉由 使用一技術從兩個或兩個以上不同組合物目標濺射沉積 所形成,該技術係選自由RF匹配網路、DC磁控管、AC 磁控管、脈衝雙極DC磁控管及RF二極體所組成之群組。 1 9.如申請專利範圍第1 8項之方法,其中該等兩個或兩個以 上目標係選自由Si02目標及丁丨目標所組成之群組,或由 02〇〇 84782 doc 200401952 約〇·5之間)及丁〗目標所 (Sii_xTix)目標(其中χ介於約o oi 組成之群組。 20.如申請專利範圍第18項之方法,纟中該基板被設置於一 夾具内,該夾具可繞軌道轉動或固定式,及/或旋轉或不 旋轉。 21 ·如申請專利範圍第i項之方法,其中該基板在一選自由空 氣、氧氣、真空所組成之群組的氣體環境中及一選自由 〇2、N2、H2、Ar、Kr、Ne、He、〇3及H2〇戶斤組成之群組 的混合氣體中受到高溫退火。 84782 doc 4-200401952 Scope of patent application: 1. An attenuation phase shift mask vacancy for lithography, including: a substrate; an etch stop layer deposited on the substrate; and an etch stop layer deposited on the etch stop layer A phase shift layer; and the phase shift mask can produce a wavelength of substantially 180 at a selected wavelength of &lt; 500 11111. Photomask with phase shift and at least 0.001% light transmission. 2. If the attenuation phase shift mask vacancy of item 丨 of the patent application range, wherein the phase shift layer includes a composite material having the formula AwBxNy0z, where A is a group selected from the group consisting of WA, VA, or VIA The group and group formed; ⑽ is selected from the group consisting of elements from group Π, group 、, group w, transition metals, steel elements, and actinides; wherein w is between about 〇1 ~ Between 0.6, X is between about 0.01 to about 0.2, y is between about 0 to about 0.6, and z is between about 0 to about 0.7. 3_ The vacant phase shift mask vacancy of item 丨, wherein the phase shift layer comprises a silicon / titanium / nitrogen / oxygen composition. 4. The vacant phase-shifting mask vacancy of item 3 in the patent application scope, wherein the silicon / titanium / nitrogen / oxygen composition has a structural formula siwTixNy〇z, where w is between about 〇1 to about 0.6, and X is Between about 0.01 to about 0, y is between about 0 to about 0.6, and z is between about 0 to about 0.7. 5. The attenuated phase shift mask according to item 1 of the application, wherein the phase shift layer has a thickness between about 400A and about 2000A. 6. The attenuation phase shift mask according to item 1 of the patent application scope, wherein the etch stop layer comprises a material selected from the group consisting of a metal or a combination material m 84782 doc _ 2004.952, wherein the combination The material includes a material selected from the group consisting of metals, elements from group π, group IV and%, nitrogen and oxygen. 7. The attenuated phase shift mask according to item 6 of the patent application, wherein the money-carrying retardation layer comprises a material selected from the group consisting of titanium and rhenium. Tian 8. The attenuation phase shift mask of item 6 of the patent application range, wherein the engraved resist layer has a thickness between about 50 people and about 500A. 9. The attenuation phase shift mask according to item 1 of the patent application, wherein the phase shift layer is SiTiO and the etch stop layer is Ta (Ta). 10. The attenuation phase shift mask according to item 1 of the application, wherein the phase shift layer is SiTiO and the etch barrier layer is titanium (Ti). 11. A method for manufacturing a vacant phase-shifting mask vacancy for lithographic etching, comprising: providing a substrate; providing a thin film for preventing propagation on the substrate; providing a phase-shifting layer on the substrate; At a selected wavelength of &lt; 500 nm, a wavelength of 180 is generated. Photomask with phase shift and at least 0.001% light transmission. 12. The method according to item 11 of the patent application scope, wherein the phase shift layer comprises a composite material having a formula AwBxNyOz, wherein a is a group selected from the group consisting of Group IVA, Group VA or VIA; b Is selected from the group consisting of an element from Group Π, Group IV, Group V, transition metals, lanthanides and actinides; wherein w is between about 0.1 to about 0, and X is introduced Between about 0.01 and about 0.2, y is between about 0 and about 0, and z is between about 0 and about 0.7. 1 3 · The method according to item 11 of the scope of patent application, wherein the phase shift layer comprises a selection of S2S; 84782 doc -2 · 200401952 free silicon / titanium / nitrogen composition and silicon / titanium / nitrogen / oxygen composition Materials that make up the group. 14. The method of claim 丨 丨, wherein the silicon / titanium / nitrogen / oxygen composition has a structural formula SiwTixNyOz, where w is between about 0.1 to about 0.06, and X is between about 0.01 to Between about 0.2, y is between about 0 and about 0, and z is between about 0 and about 0.7. 1 5 · The method according to item 1 of the patent application range, wherein the phase shift film is formed by sputter deposition from two or more different composition targets using a technique selected from the RF matching network Circuit, DC magnetron, AC magnetron, pulsed bipolar DC magnetron and RF diode. 16. The method according to item 15 of the patent application scope, wherein the phase shift layer is formed by using a method to deposit from a target of a composite material (Sil-xTix), wherein X is between about 0.01 and about 0.5 The method is selected from the group consisting of an RF matching network, a DC magnetron, an AC magnetron, a pulsed bipolar DC magnetron, and an RF diode. 17 • The method according to item 15 of the scope of patent application, wherein the substrate is set in a jig ', the jig can be rotated or fixed around a track, and / or rotated or not rotated. 18. The method of claim 11 in which the phase shift film is formed by sputter deposition from two or more targets of different compositions using a technique selected from the group consisting of an RF matching network, A group of DC magnetrons, AC magnetrons, pulsed bipolar DC magnetrons and RF diodes. 1 9. The method according to item 18 of the scope of patent application, wherein the two or more targets are selected from the group consisting of a SiO2 target and a Ding target, or from 02〇84782 doc 200401952 about 0 · 5) and Dii ’s target (Sii_xTix) target (where χ is a group consisting of about o oi. 20. According to the method of claim 18 in the scope of patent application, the substrate is set in a fixture, the The fixture can be rotated or fixed around the track, and / or rotated or not rotated. 21 · The method according to item i of the patent application, wherein the substrate is in a gas environment selected from the group consisting of air, oxygen, and vacuum And a mixture of gases selected from the group consisting of 02, N2, H2, Ar, Kr, Ne, He, 03, and H2 0 jin subjected to high temperature annealing. 84782 doc 4-
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