Patent ID: 6342444
Filing Date: 2002-01-29
Classification: H01L

Abstract:
A method of forming a diffusion barrier for copper interconnects comprising the steps of:forming an insulation film on a substrate; selectively forming an etching mask on the insulation film; forming a trench by selective removal of the insulation film using the etching mask; forming a Cu wiring in the trench with at least some parts of the etching mask remaining; forming a barrier material on the etching mask and the Cu wiring; forming a metal nitride by reacting between the etching mask and the barrier material on the Cu wiring by heat-treatment of the barrier material in an atmosphere of nitrogen, and nitriding the barrier material on the Cu wiring to form a diffusion barrier layer against Cu diffusion and oxidation; and removing the barrier material selectively on the etching mask after nitriding the barrier material, and making the diffusion barrier layer remained selectively on the Cu wiring.