Finfet semiconductor structures and methods of fabricating same

Abstract

The invention provides a method of forming a semiconductor structure, which include: providing an intermediate semiconductor structure having semiconductor substrate, a fin having an EG oxide layer in contact with at least a portion of the fin, and a gate stack disposed over a portion of the fin; forming a silicon nitride layer over portions of the fin that are not located under the gate stack; and after forming the silicon nitride layer, performing one or more ion implantation steps on the intermediate semiconductor structure. The invention also provides a method of forming a semiconductor structure including: providing an intermediate semiconductor structure having a semiconductor substrate, a fin having an EG oxide layer in contact with at least a portion of the fin, and a gate material disposed over the fin; forming, over the fin and gate material of the intermediate semiconductor structure, a gate stack hardmask including an oxide layer; forming a silicon nitride barrier layer on the oxide layer of the gate stack hardmask; performing one or more gate stack hardmask patterning steps; removing the EG oxide layer from portions of the fin that are not located under the gate; and subsequent to removing the EG oxide layer from portions of the fin that are not located under the gate, performing one or more ion implantation steps.