Stacked nanosheet device with step configuration where the bottom nanosheet stack is wider than the top nanosheet stack

Abstract

An etch stop layer is provided in a vertical stack containing a bottom material stack and a top material stack. Notably, the etch stop layer is provided in an area in which a step region is desired and thus during the etch use to provide the step region the etch stops on the etch stop layer without tapering or compromising the height of the top material stack. Also, prior to gate formation, a dielectric oxide is formed in an area in proximity to the nanosheet step region and a portion thereof remains in the structure after nanosheet and functional gate structure formation.