Double-patterning, topcoat-less photoresists and silicon hard masks

摘要

The spin-on silicon anti-reflective coating (or SiARC) material is placed between the resist and an underlying organic planarizing layer, also called carbon underlayer, forming a tri-layer scheme for ArF immersion lithography processes. The optical properties for the SiARC and underlayer can be individually tuned to match a particular lithography setup, minimizing substrate reflectivity into the resist as much as possible, typically below 0.5% or lower.