Patent ID: 10347740

Abstract:
A method of forming a FinFET fin with low-doped and a highly-doped active portions and/or a FinFET fin having tapered sidewalls for Vt tuning and multi-Vt schemes and the resulting device are provided. Embodiments include forming an Si fin, the Si fin having a top active portion and a bottom active portion; forming a hard mask on a top surface of the Si fin; forming an oxide layer on opposite sides of the Si fin; implanting a dopant into the Si fin; recessing the oxide layer to reveal the active top portion of the Si fin; etching the top active portion of the Si fin to form vertical sidewalls; forming a nitride spacer covering each vertical sidewall; recessing the recessed oxide layer to reveal the active bottom portion of the Si fin; and tapering the active bottom portion of the Si fin.