METHOD FOR FORMING TANTALUM NITRIDE FILM

摘要

A Ta-rich tantalum nitride film is formed as follows: a raw material gas composed of a coordinate compound in which an N=(R,R') group (wherein R and R' may be the same as or different from each other and respectively represent an alkyl group having 1-6 carbon atoms) is coordinated to a Ta element is introduced into a vacuum chamber and adsorbed on a substrate; next a halogen gas is introduced therein for forming a TaN<SUB>x</SUB>(Hal)<SUB>y</SUB>(R,R')<SUB>z</SUB> compound (wherein Hal represents a halogen atom); and then an activated reaction gas is introduced therein for cutting and removing N bonded to Ta, the Hal bonded to N, and the R(R') group bonded to N. Consequently, a low-resistance tantalum nitride film having low C and N contents, high Ta/N ratio and secure adhesion to a Cu film can be obtained, and this tantalum nitride film is useful as a barrier film. By implanting tantalum particles into the thus-obtained film by sputtering, there can be obtained a still tantalum-richer film.