Incorporation of ionic photoacid generator (PAG) and base quencher into the resist polymer main chain for sub-50 nm resolution patterning

Abstract

Previous research has shown that polymer-bound PAG resists exhibit improved lithographic performance in both 193 nm and extreme ultraviolet lithography (EUVL) applications as compared to their more traditional blended PAG analogs. The further incorporation of base directly into the resist polymer backbone is a potential route for improving the resist performance and processing window. In this work, a new series of chemically amplified resists (CARs) that incorporate both PAG and base quencher functional groups into the polymer main chain are reported. The lithographic performance of these materials was investigated using electron-beam lithography (EBL). The polymer-bound PAG cation resist showed higher photospeed than the polymer-bound PAG anion resists. Base quencher incorporation slightly decreased the photospeed but improved the resolution in the case of resists with the polymer-bound PAG cation and pyridine base. Base quencher incorporation showed no improvement on the lithographic performance of polymer-bound PAG anion resists.