International Business Machines Corporation
Interconnect structures with cobalt-infused ruthenium liner and a cobalt cap

Abstract:

An interconnect structure, and a method for forming the same includes forming recess within a dielectric layer and conformally depositing a barrier layer within the recess. A cobalt-infused ruthenium liner is formed above the barrier layer, the cobalt containing ruthenium liner formed by stacking a second liner above a first liner, the first liner positioned above the barrier layer. The first liner includes ruthenium while the second liner includes cobalt. Cobalt atoms migrate from the second liner to the first liner forming the cobalt-infused ruthenium liner. A conductive material is deposited above the cobalt-infused ruthenium liner to fill the recess followed by a capping layer made of cobalt.