High-Aspect-Ratio Alkaline Surface Treatment Method of Dyed Photoresist

Abstract

Contrast enhancement by alkaline surface treatment of dyed photoresist is characterized. A surface-modified layer formed by the alkaline surface treatment prevents unexposed areas of the resist from being dissolved and acts as a barrier during development. Utilizing alkaline surface treatment, high-aspect-ratio submicron patterns on a highly reflective substrate are successfully delineated with negligible resist thickness loss. It is found that this modified process is enhanced by baking before exposure.