In chemically amplified resists for extreme ultraviolet (EUV) and electron beam (EB) lithographies, the reaction
mechanism of acid generation is different from that for photolithography. However, details of acid generation are still
unclear. In particularly, details of the deprotonation dynamics of radical cations in solid resist films have not been
investigated. The dynamics of radical cations of resist polymer is important for understanding proton generation.
Poly(4-hydroxystyrene) (PHS) is a typical polymer for EUV and EB lithographies. We observed the dynamics of PHS radical cation in PHS film by using pulse radiolysis.
In chemically amplified resists, amines (base compounds) play important roles such as the　control of acid diffusion, the sharpening of image slope and the improvement of environmental resistivity of resist materials. However, the details in the reactions between amines and protons in solid films are still unknown. In this research, we have investigated the neutralization of acids by amines in poly(4-hydroxystyrene) (PHS). Proton dynamics in the presence of amines in PHS films is discussed.