Realization of ultra-thin HSQ resist layer for high resolution electron beam lithography using liquid splitting process

摘要

In this work we report on a novel method to realize ultra-thin hydrogen silsesquioxane (HSQ) resist layers with a resist thickness of 20 nm and below. Unlike conventional methods such as dilution of HSQ or spin coating at very high rotation speeds, our method reduces an initial resist layer thickness by means of liquid splitting. An initial HSQ resist layer thickness of 40 nm was thinned to 20 nm and a successful pattern definition down to a resolution of 15 nm was achieved by using a standard electron beam lithography process on the thinned resist layer. Hence, our method allows simple and effective preparation of sub-20 nm HSQ resist layers for dense patterns with ultimate resolution.