Recessed local interconnect formed over self-aligned double diffusion break

Abstract

An approach for creating a buried local interconnect around a DDB (double diffusion break) to reduce parasitic capacitance on a semiconductor device is disclosed. The approach utilizes a metal, as the local interconnect, buried in a cavity around the DDB region of a semiconductor substrate. The metal is disposed by two dielectric layers and the substrate. The two dielectric layers are recessed beneath two gate spacers. The buried local interconnect is recessed into the cavity where the top surface of the interconnect is situated below the top surface of the surrounding S/D (source/drain) epi (epitaxy). The metal of the local interconnect can be made from W, Ru or Co.