International Business Machines Corporation
Double metal double patterning with vias extending into dielectric

Abstract:

A method is presented for constructing a dual metal interconnect structure. The method includes forming a trilayer stack over a dielectric layer, forming a plurality of vias extending through the trilayer stack and into the dielectric layer, depositing a first conductive material to fill the plurality of vias, etching the first conductive material to form first conductive regions, depositing a spacer, etching the spacer to form spacer portions adjacent the first conductive regions, and depositing a second conductive material.