Semiconductor device and methods of formation

Abstract

Spacer layers on sidewalls of a dummy gate structure included in a semiconductor device are trimmed or etched prior to or during a replacement gate process in which the dummy gate structure is replaced with a replacement gate structure. A radical surface treatment operation is performed to etch the spacer layers, which is a type of plasma treatment in which radicals are generated using a plasma. The radicals in the plasma are used to etch the spacer layers such that the shape and/or the geometry of the remaining portions of the spacer layers reduces, minimizes, and/or prevents the likelihood of an antenna defect being formed in the spacer layers and/or in a work function metal layer of the replacement gate structure. This reduces, minimizes, and/or prevents the likelihood of occurrence of damage and/or defects in the replacement gate structure in subsequent processing operations for the semiconductor device.