Study of bottom anti-reflection coated and Fabry-Perot type anti-reflection coated on photomask for vacuum ultraviolet lithography

• Main Authors: Yi-Fen Chuang, 莊怡芬
• Other Authors: Cheng-Chung Lee
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/55648599084481806528

碩士 === 國立中央大學 === 光電科學研究所 === 90 === There are two major parts in this thesis. One is to establish the anti-reflection coating technique for using in vacuum ultraviolet photomask . The other is to investigate the bottom anti-reflection coating. In the development of the anti-reflection coating technique for photomask applications, we demonstrated an anti-reflection coating structure for vacuum ultraviolet binary mask , which is based on three layers Fabry-Perot structure . The anti-reflection coating structure is composed of Chrome (Cr) / Oxide (SiO2) / Chrome (Cr) stack. After adding different optimization , reflectance of less than 2% at both 193 nm and 157 nm have been achieved. At the three-layer Fabry-Perot structure, the bottom chrome layer provides suitable absorption. By controlling the thickness of the intermediate silicon oxide layer, we can tune the minimum reflection regime to the desired exposure wavelength. The top metal layer can prevent charge accumulation during e-beam writing .The difference between the Fabry-Perot structure and traditional structure Chrome Oxide (Cr2O3 ) / Chrome (Cr) is that the top metal layer can prevent charge accumulation during e-beam writing. The structures are therefore expected to have great potential as antireflective coating structure in high performance binary mask. In the development of the bottom anti-reflection coating technique , the thinfilm structure is bilayer which is composed of TEOS Oxide (SiO2) / Silicon Nitride (SiN) both are deposited by Plasma Enhanced Chemical Vapor Deposition , PECVD . By changing the thickness of thinfilms , reflectance can be reduced to less than 1% and 3% at 157nm and broadband of 193 nm to 157 nm respectively .