Method for forming tantalum nitride film

Abstract

A tantalum nitride film-forming method comprises the steps, according to the CVD technique, of introducing a raw gas consisting of a coordination compound constituted by an elemental tantalum (Ta) having a coordinated ligand represented by the general formula: N═(R, R') (in the formula, R and R′ may be the same or different and each represents an alkyl group having 1 to 6 carbon atoms) and a halogen gas into a film-forming chamber to thus form a film of a halogenated compound represented by the following general formula: TaN(Hal)(R, R′)(in the formula, Hal represents a halogen atom), reacting the halogenated compound film with a hydrogen atom-containing gas by the introduction thereof into the chamber to thus form a tantalum nitride film rich in tantalum atoms. The resulting tantalum nitride film has a low resistance, low contents of C and N, and a high compositional ratio: Ta/N, can ensure high adherence to the electrical connection-forming film and can thus be useful as a barrier film. Moreover, tantalum particles are implanted in the resulting film according to the sputtering technique to thus further enrich the film with tantalum.