Semiconductor device having nanosheet transistor and methods of fabrication thereof

Abstract

Embodiments of the present disclosure provide a semiconductor device structure. In one embodiment, the semiconductor device structure includes a plurality of semiconductor layers vertically stacked over a substrate, a source/drain feature in contact with each of the plurality of the semiconductor layers, a gate electrode layer surrounding a portion of each of the plurality of the semiconductor layers, a source/drain contact disposed above the source/drain feature, a gate spacer disposed between the gate electrode layer and the source/drain contact, and an isolation structure extending through the gate electrode layer. The isolation structure includes a first portion having three sides covered by the gate electrode layer, the first portion having a top surface at a first elevation, and a second portion extended outwardly from the first portion, the second portion having a top surface at a second elevation that is lower than the first elevation.