International Business Machines Corporation
Modulating metal interconnect surface topography

Abstract:

A metal interconnect structure can be fabricated within an integrated circuit (IC). A recess can be created in an IC dielectric layer and a surface modulation liner can be formed by depositing two different metallic elements onto the surfaces of the recess. One metallic element can have a standard electrode potential greater than a standard electrode potential of an interconnect metal, and the other metallic element can have a standard electrode potential less than the standard electrode potential of the interconnect metal. A metal interconnect structure can be formed by filling the remainder of the recess with interconnect metal, which is physically separated from the dielectric layer by the surface modulation liner. The surface topography of the metal interconnect structure can be modulated with a polishing process, by removing a top portion of the interconnect metal and a top portion of the surface modulation liner.