Disclosed are embodiments of a semiconductor structure that includes one or more multi-gate field effect transistors (MUGFETs), each MUGFET having one or more semiconductor fins. In the embodiments, dopant implant region is incorporated into the upper portion of the channel region of a semiconductor fin in order to selectively modify (i.e., decrease or increase) the threshold voltage within that upper portion relative to the threshold voltage in the lower portion and, thereby to selectively modify (i.e., decrease or increase) device drive current. In the case of a multiple semiconductor fins, the use of implant regions, the dopant conductivity type in the implant regions and/or the sizes of the implant regions can be varied from fin to fin within a multi-fin MUGFET or between different single and/or multi-fin MUGFETs so that individual device drive current can be optimized. Also disclosed herein are embodiments of a method of forming the semiconductor structure.