Al2O3-TiO2非晶複合膜應用於193奈米波長之高穿透率衰減式相位偏移光罩之光學特性研究

Optical properties of the amorphous Al2O3-TiO2 composite film for H-T APSM at 193nm wavelength

李鑫(Shin Lee)

指導教授 ： 黃繼遠

大同大學/工程學院/材料工程學系所/碩士(2005年)

摘要

利用R.F. 磁控濺鍍於室溫下在含氮氣和氧氣的氣氛中鍍製(Al2O3)x-(TiO2)1-x非晶複合膜。(Al2O3)x-(TiO2)1-x複合膜於O2/Ar流量比為2時是完全氧化的。(Al2O3)x-(TiO2)1-x複合膜之光學常數和(Al2O3)x-(TiO2)1-x複合膜中Al2O3的莫耳分率是呈現線性的關係。符合高穿透率衰減式相位偏移光罩(HT-APSM)之光學要求的光學常數可藉由調整(Al2O3)x-(TiO2)1-x複合膜中Al2O3的莫耳分率來達成。計算出符合使用於ArF 193nm微影技術之HT-APSM之光學要求的 (Al2O3)x-(TiO2)1-x複合膜之Al2O3莫耳分率範圍為78%~86%。在193nm波長下的反射率小於10%且在257nm波長下的檢測穿透率小於50%都符合在HT-APSM中關鍵的2個光學要求。為了得到具有最佳穿透率為20%之HT-APSM，我們製備出一Al2O3-TiO2複合膜，其光學性質符合ArF–line HT-APSM之最佳光學要求。所有膜之化學抗蝕性測試後之表面粗糙度和附著性測試皆符合要求。故單層Al2O3-TiO2複合膜對於使用HT-APSM去設計出65nm線寬之圖形來說是一可考慮的新材料。

關鍵字

高穿透率衰減式相位偏移光罩

並列摘要

Amorphous (Al2O3)x-(TiO2)1-x composite films are prepared using R.F. unbalanced magnetron sputtering in an atmosphere of argon and oxygen at room temperature. (Al2O3)x-(TiO2)1-x composite films are completely oxidized using an O2/Ar flow rate ratio of 2.0. The optical constants of (Al2O3)x-(TiO2)1-x composite films are linearly dependent on Al2O3 mole fraction in (Al2O3)x-(TiO2)1-x composite film. By tuning the Al2O3 mole fraction in the (Al2O3)x-(TiO2)1-x composite films, the optical constants can meet the optical requirements for a high transmittance attenuated phase shift mask (HT-APSM) blank. It can be found that the Al2O3 mole fraction in (Al2O3)x-(TiO2)1-x composite films which meet the optical requirements at 193 nm wavelength of an HT-APSM blank in ArF lithography is calculated to be between 78% and 86%. The reflectance of less than 10% at 193 nm wavelength and the inspection transmittance of less than 50% at 257 nm wavelength meet two key optical requirements for an HT-APSM blank. In order to obtain an HT-APSM blank with optimized transmittance of 20%, one Al2O3-TiO2 composite film is fabricated and its optical properties meet the optimized optical requirements for ArF –line HT-APSM blanks. All the films meet the requirements of surface roughness after the chemical durability test and the adhesion test. Therefore, monolayer Al2O3-TiO2 composite film is a new candidate material for HT-APSM blanks to be utilized to design fine pattern with dimensions as small 65nm.

並列關鍵字

H-T APSM

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