Patent ID: 9553191
Date: 2017-01-24
CPC Classifications: H01L

Claim:
1. A method of fabricating a fin field effect transistor (FinFET), comprising: patterning a semiconductor substrate to form a plurality of trenches in the semiconductor substrate and at least one semiconductor fin between the trenches; forming a plurality of insulators in the trenches; forming a gate stack over portions of the semiconductor fin and over portions of the insulators; and forming a strained material doped with a conductive dopant over portions of the semiconductor fin revealed by the gate stack, the strained material being formed by selectively growing an epitaxial layer with a gradient doping concentration of the conductive dopant, the gradient doping concentration being from a first concentration to a second concentration as a time of selectively growing the epitaxial layer passes, and the first concentration being higher than the second concentration.