International Business Machines Corporation
Interconnect structures including self aligned vias

Abstract:

Back end of line metallization structures and methods for fabricating self-aligned vias. The structures generally include a first interconnect structure disposed above a substrate. The first interconnect structure includes a metal line formed in a first interlayer dielectric. A second interconnect structure overlies the first interconnect structure. The second interconnect structure includes a second cap layer on the first interlayer dielectric, a second interlayer dielectric thereon, and at least one self-aligned via in the second interlayer dielectric conductively coupled to at least a portion of the metal line of the first interconnect structure, wherein any misalignment of the at least one self-aligned via results in the at least one self-aligned via landing on both the metal line of the first interconnect structure and the second cap layer. The second cap layer is an insulating material.