Low undercut n-p work function metal patterning in nanosheet replacement metal gate process

Abstract

A semiconductor structure comprises a semiconductor substrate, an N-type stacked nanosheet channel structure formed on the semiconductor substrate, and a P-type stacked nanosheet channel structure formed adjacent to the N-type stacked nanosheet channel structure on the semiconductor substrate. Each of the adjacent N-type and P-type stacked nanosheet channel structures comprises a plurality of stacked channel regions with each such channel region being substantially surrounded by a gate dielectric layer and a gate work function metal layer, and with the gate work function metal layer being separated from the channel regions by the gate dielectric layer. The gate dielectric and gate work function metal layers of the adjacent N-type and P-type stacked nanosheet channel structures are substantially eliminated from a shared gate region between the adjacent N-type and P-type stacked nanosheet channel structures.