Self-aligned contact (sac) in nanosheet transistors

Abstract

Embodiments of the invention include a method for fabricating a semiconductor device and the resulting structure. A nanosheet stack of alternating nanosheets of a sacrificial semiconductor material nanosheet and a semiconductor channel material nanosheet and a dielectric nanosheet as a top layer of the nanosheet stack is provided above a semiconductor substrate. A dummy gate with a gate cap and spacers on the sidewalls straddle over the nanosheet stack. End portions of the sacrificial semiconductor material nanosheets are recessed. A dielectric spacer material layer is formed. A source/drain region is formed on the sidewalls of each semiconductor channel material nanosheet. The dummy gate and gate cap are removed. Each sacrificial semiconductor material nanosheet is removed. A functional gate structure is formed that wraps around each suspended semiconductor channel material nanosheet. A self-aligned source/drain contact region is formed. A gate contact region is formed in a trench in the semiconductor substrate.