International Business Machines Corporation
Fully Aligned Via for Interconnect

Abstract:

A fully aligned via interconnect structure and techniques for formation thereof using subtractive metal patterning are provided. In one aspect, an interconnect structure includes: metal lines Mx-1; metal lines Mx disposed over the metal lines Mx-1; and at least one via Vx-1 fully aligned between the metal lines Mx-1 and the metal lines Mx, wherein a top surface of at least one of the metal lines Mx-1 has a stepped profile. In another aspect, another interconnect structure includes: metal lines Mx-1; metal lines Mx disposed over the metal lines Mx-1; at least one via Vx-1 fully aligned between the metal lines Mx-1 and the metal lines Mx; and sidewall spacers alongside the metal lines Mx. A method of forming an interconnect structure is also provided.