Lithographic characteristics of 193-nm resists imaged at 193 and 248 nm

Abstract

During the past few years an intensive effort has been made to develop 193 nm photoresists for the next generation of DUV lithography tools. The early portion of this effort was focused on the development of photoresist polymers that are transparent at 193 nm. Since the polyacrylic materials developed for 193 nm lithography were not highly reactive ion etch (RIE) resistant, recent 193 nm resist polymer efforts have focused on both optical transparency and RIE etch resistance. Most of these polymers developed for 139 nm lithography are highly transparent at 248 nm. This dual transparency produces the option of developing a resist that is backward compatible, i.e. imagable at both 193 nm and 248 nm. This paper will investigate the lithographic characteristics of resists initially developed for use at 193 nm, but imaged at both 193 nm and 248 nm. Various resist families will be compared, and aspects such as absorbance effects and PROLITHH/2™ simulations will be taken into consideration. ©2003 Copyright SPIE - The International Society for Optical Engineering.