Basic aspects of acid generation processes in chemically amplified resists for electron beam lithography

Acid generation processes of chemically amplified resists for electron beam (EB) lithography are different from those of chemically amplified photoresists. In chemically amplified EB resists, the role of acid generators is to produce not protons but counter anions of acids through the reactions with low energy electrons generated at ionization events. As the distribution of counter anions determines latent acid image, the dynamics of low energy electrons is important in EB lithography. In this paper, we made clear the effects of dielectric constants of base polymers, the initial separation distances between radical cations and electrons, and the reaction radii of acid generators on the sensitivity and resolution of chemically amplified resists.