Measuring acid generation efficiency in chemically amplified resists with all three beams

Abstract

A method for measuring acid generation efficiency is presented and utilized to determine the relative efficiency of four photoacid generators (PAGs) upon radiation with photon, electron, and ion beams. In this method, chemically amplified resists are prepared with varying amounts of base, coated into thin films (1000 Å), and exposed. Linear plots of the base concentration against the threshold exposure dose for each resist yield the threshold acid concentration and the acid generation rate constant for each PAG. The acid-generating efficiency of the four PAGs (ND-Tf, TPS-Tf, TBI-PFOS, and TBI-Tf) upon irradiation with DUV (248 nm), EUV (13.4 nm), x-ray (1 nm), e beam (30 and 50 keV), and He+ ions is evaluated.