Method for improving the adhesion and durability of CVD tantalum and tantalum nitride modulated films by plasma treatment

摘要

A method for forming modulated tantalum/tantalum nitride diffusion barrier stacks on semiconductor device substrates used in interconnect structures. Alternating layers of tantalum and tantalum nitride are deposited onto the semiconductor device substrate by chemical vapor deposition from a tantalum pentafluoride precursor vapor, with intermittent ammonia plasma treatment of the tantalum and tantalum nitride such that each tantalum layer and each tantalum nitride layer are treated at least once to thereby reduce the evolution of HF gas, thereby improving the adhesion and durability of the film stacks during subsequent elevated temperature processing.