International Business Machines Corporation
INTERCONNECT STRUCTURES WITH SELECTIVE CAPPING LAYER

Abstract:

A method includes forming a first metallization layer containing a first metal-containing line and a second metal-containing line disposed in a first interlevel dielectric layer. The first metal-containing line includes a first conductive metal and the second metal-containing line includes a second conductive metal. The first metal-containing line and the second metal-containing line are recessed to below a top surface of the interlevel dielectric layer. A metal-containing cap protection layer is deposited in a recessed portion of the first metal-containing line and the second metal-containing line. The metal-containing cap protection layer includes a third conductive metal which is different than the first conductive metal and the second conductive metal.