Photoresist analysis to investigate LWR generation mechanism

In order to understand the mechanism of line width roughness (LWR) generation and to find control knobs for improving resist patterning properties, we developed precise direct analysis method of resist patterns. This method comprise three important processes: 1. Selective sampling of resist pattern surface and pattern core, 2. Analysis and preparative isolation of collected resist ingredient by mu GPC, 3. Structural analysis by Py-GC/MS. mu GPC and Py-GC/MS analysis provid resist ingredient distribution information inside resist pattern, which includes original polymer, reacted polymer, and photo acid generator (PAG) through the ArF patterning process. This novel analytical method can provide remarkably helpful information about identifying proper control knobs for lithographic performance of ArF resist and for next generation lithography (NGL), especially extreme ultra violet lithography (EUVL) materials, where exposure tool time is very limited.