Develop gap-fill process of shallow trench isolation in 450mm wafer by advanced Flowable CVD technology for sub-20nm node

Abstract

In this study, a novel Flowable CVD process using non-carbon silicon based precursor has been developed for gap filling in 450mm wafer level, sub-20nm STI structure. To achieve 450mm wafer with aspect ratio 5:1 STI structure, guided DSA patterning and a-carbon hard-mask are applied. The various conditions have been screened in deposition, cure and anneal processes in order to result a void free and less Si damage performance. By SEM viewing and FT-IR analysis, the gap-fill profile and mechanism of film conversion are discussed.