Sensitization of polymethacrylate resist with adding acid-generating promoters upon exposure to EUV light

Abstract

Abstract With the advancement of EUV lithography, the development of higher performance resist materials has been required. Recently, the EUV sensitivity of chemically amplified resists has been improved by adding an acid-generating promoter (AGP) such as DTS (p-tolyl diphenyl sulfone). However, the details of the mechanism of sensitivity enhancement were still unclear. In this study, we investigated the EUV sensitivity, dissolution characteristics during development after EUV irradiation, and patterning characteristics by electron beam lithography with the addition of AGP to the acrylate polymers. The addition of DTS showed an increase in sensitivity with DTS concentration. We also discuss other than the increase in initial acid yield that lead to enhanced sensitivity by addition of DTS.