New Silicon Hard Mask Material Development for sub 5 nm Node

摘要

New spin-on silicon hard mask (Si-HM) material containing Si-C structure in main chain was developed to meet EUVlithography performance, etch requirements and non-lithography patterning applications at sub 5 nm node. New Si-HMmaterial can be used as an alternative to traditional polysiloxane Si-HM. It showed 2.5X high resistance for oxygenetching compared to polysiloxane Si-HM structure due to low electronegative gap and higher silicon content. It can bechemically modified with various functional units, and photoresist adhesion control would be expected to improve. Wealso observed sensitivity improvement from EUV lithography tri-layer patterning process including new Si-HM. Wetstrip-ability with DHF and refractive index at 193 nm were changed significantly for this new Si-HM before and afterUV irradiation under air. It also showed excellent gap-fill performance at narrow pattern dimensions on our patternedwafers.