Dependence of acid generation efficiency on the protection ratio of hydroxyl groups in chemically amplified electron beam, x-ray and EUV resists

Abstract

In chemically amplified resists for ionizing radiation such as an electron beam, protons of acids come from not acid generators but base polymers. This means that the modification of base polymers has a great effect on the acid generation efficiency. The relation between relative acid yield and protecting groups of poly(4-hydroxystyrene) was examined. The selection of protecting groups is important for the acid generation efficiency and the acid distribution uniformity.