Low-Temperature Deposition of Silicon Dioxide and Silicon Nitride for Dual Spacer Application

Abstract:  Abstract Advanced sub 65 nm spacer applications require high quality conformal silicon dioxide and silicon nitride deposition processes at low thermal budgets. In this paper, we report on a study where these films were deposited using a novel Si precursor material that enables high deposition rates at temperatures typically around 250degC using a production-proven single wafer chemical vapor deposition (CVD) system (Planar 300trade) from Aviza Technology. Films are deposited with excellent non-uniformities, step coverage over challenging device structures and low particle counts. The reported silicon dioxide process is a purely thermal CVD process, whereas the silicon nitride process uses an RF plasma to initiate ammonia reactivity. The use of a single platform and single C- and Cl-free Si precursor enables sequential processing of C- and CI- free SiO2 and SiN dual spacer layers at processing temperatures (< 400degC) compatible with advanced devices.