Effect of composition uniformity in the polymer chain of EUV photoresist on lithographic performance

Abstract

Extreme ultraviolet (EUV) lithography is the most promising technology for the fabrication in ultrafine pattern, using 13.5nm light. At tighten CD and pitches of C/H and L/S patterns, local variations in the resist films are key challenges that must be addressed in EUV photoresists to improve CDU and LWR. Due to the nature of polymer synthetic process for chemically amplified resist (CAR), there will be significant differences in composition, molecular weight, and order of polymer chains. Composition uniformity in the polymer chains of EUV photoresist will be one of critical factors to lead for good performance. In this study, polymers with different composition distributions depending on synthetic process were synthesized and monitored the conversion rate of monomers. The key properties of their resist films were characterized to identify its effect on resist characteristics. Structure and performance relationship will be presented by EUV lithographic performance comparison.