Gel permeation chromatography analysis of remaining components of electron-beam-irradiated ZEP520A resist after development

Abstract Stochastic defects including line edge roughness are a significant problem in nanofabrication. In this study, the components of ZEP520A electron beam (EB) resist remaining after development were investigated by gel permeation chromatography. When the resist was irradiated with EB at a moderate dose, which corresponds to the dose at the boundary between resist patterns and spaces, low-molecular-weight components were preferentially dissolved in the developer and high-molecular-weight components remained. Consequently, the film density is considered to have become lower than its initial value. Such dissolution behavior is likely to contribute to the formation of a rough resist surface.