Chemical Conditions of SiCNO Film Exposed to ClF₃ Gas

Abstract

A SiCNO film containing 28% nitrogen was formed by plasma-enhanced chemical vapor deposition with no heating assistance using SiH 3 CH 3 , N 2 and Ar gases. The 15 nm thick layer of the film was then etched off utilizing 10% ClF 3 gas at room temperature for 1 min. After etching, the fluorine and chlorine concentrations within the film did not increase but they became higher at the surface. The removal rate of Si-N component was considered to be faster than that of Si-C, Si-O and C-N components, based on the X-ray photoelectron spectroscopy results. Overall, the etching was considered to occur following the etching behavior of the components formed between four elements, that is, Si, C, N, and O.