Effects of the statistical fluctuation of PAG and quencher concentration on LWR of ArF resists

摘要

In order to improve line width roughness (LWR) of chemically amplified resists (CARs) without trade-offs with other lithographic performances such as exposure latitude (EL) and sensitivity, we investigated effects of the spatial fluctuation of sensitivity on LWR of ArF resists. Compared a statistical model with experiments, it was clarified that LWR of ArF resists was caused by the fluctuation of sensitivity due to the fluctuation of the PAG and quencher concentration. Furthermore, we developed novel photoactive materials such as a transparent PAG and an nPAG-1Amine which were predicted to be useful for reducing the statistical fluctuation of sensitivity by the theoretical model. LWR was successfully improved using these photoactive materials. This study not only provided new insight into the root cause of LWR, but also proved efficacy of the theory-based material design.