US 6,153,935 A · Dual etch stop/diffusion barrier for damascene interconnects

Abstract

A damascene interconnect containing a dual etch stop/diffusion barrier. The conductive material of the damascene interconnect is capped with a conductive metal diffusion barrier cap, typically using electroless deposition, and, optionally, with a dielectric etch-stop layer. An optional chemical mechanical polish-stop layer may also be present. The different methods of the invention allow the CMP stop, reactive-ion etch stop, and metal diffusion barrier requirements of the different layers to be decoupled. A preferred conductive material is copper.

Claims22

Dependent claims

A structure comprising:

a substrate;
a dielectric layer over the substrate;
a chemical mechanical polish-stop layer over the dielectric layer, the chemical mechanical polish-stop layer having an upper surface;
an opening in the dielectric layer and the chemical mechanical polish-stop layer;
a conductive liner lining the opening;
a conductive material filling the opening and in electrical contact with the conductive liner, the conductive material having an upper surface coplanar with the upper surface of the chemical mechanical polish-stop layer;
and
a conductive metal diffusion barrier cap over the conductive material and in contact with the conductive material.

5 more elements

Dependencies are inferred from the claim text.

Dual etch stop/diffusion barrier for damascene interconnects

Life of this patent

Dual etch stop/diffusion barrier for damascene interconnects

Life of this patent

Abstract

Claims22