Analysis of stochastic effects in chemically amplified poly(4-hydroxystyrene-co-t-butyl methacrylate) resist

作者：Kozawa Takahiro^*; Santillan Julius Joseph; Itani Toshiro

来源：Japanese Journal of Applied Physics, 2016, 55(7): 076501.

DOI：10.7567/JJAP.55.076501

Understanding of stochastic phenomena is essential to the development of a highly sensitive resist for nanofabrication. In this study, we investigated the stochastic effects in a chemically amplified resist consisting of poly(4-hydroxystyrene-co-t-butyl methacrylate), triphenylsulfonium nonafluorobutanesulfonate (acid generator), and tri-n-octylamine (quencher). Scanning electron microscopy (SEM) images of resist patterns were analyzed by Monte Carlo simulation on the basis of the sensitization and reaction mechanisms of chemically amplified extreme ultraviolet resists. It was estimated that a +/-0.82 sigma fluctuation of the number of protected units per polymer molecule led to line edge roughness formation. Here, sigma is the standard deviation of the number of protected units per polymer molecule after postexposure baking (PEB). The threshold for the elimination of stochastic bridge generation was 4.38 sigma (the difference between the average number of protected units after PEB and the dissolution point). The threshold for the elimination of stochastic pinching was 2.16 sigma.

• 出版日期2016-7