Enhancing the Novolak resin resist resolution by adding phenol to fractionated resin

Abstract

Novolak resists have been widely used in IC production and are still used in the production of flat panel displays (FPDs) and MEMS. However, with the advent of high-definition products, FPDs increasingly face requirements for finer dimensions. These trends have generated requirements for higher sensitivity, higher resolution, and wider process margin for novolak resists. Using a lithography simulator with the goal of improving the performance of novolak resists, we examined various approaches to improving resist materials. This report discusses efforts to improve resolution and sensitivity using highly fractionated novolak resins and adding low molecular weight phenol resins.