Deposition of Ta-N thin films as diffusion barrier

Abstract

Sputtered Ta-N thin films have been known to be an attractive interlayer between Cu and Si metallization as diffusion barrier. They have many good properties from the diffusion barrier point of view. They have high melting point (3293 K) and therefore expected to have high activation energy for both lattice and grain boundary diffusion. It does not form intermetallic compounds with copper and thus provides a stable interface between copper and silicon.