Doping of copper wiring structures in back end of line processing

摘要

A method of forming a metal interconnect structure includes forming a copper line within an interlevel dielectric (ILD) layer; directly doping a top surface of the copper line with a copper alloy material; and forming a dielectric layer over the ILD layer and the copper alloy material; wherein the copper alloy material serves an adhesion interface layer between the copper line and the dielectric layer.

主权项

1. A metal interconnect structure, comprising:
a copper line formed within an interlevel dielectric (ILD) layer; a barrier layer surrounding bottom and sidewall surfaces of the copper line, with a sidewall of the copper line having a sidewall copper alloy concentration; a top surface of the copper line directly doped with a copper alloy material, the top surface of the copper line having a top copper alloy concentration, wherein the top copper alloy concentration is greater than the sidewall copper alloy concentration; and a dielectric layer formed over the ILD layer and the copper alloy material; wherein the copper alloy material serves an adhesion interface layer between the copper line and the dielectric layer.