Patent ID: 9634087
Date: 2017-04-25
CPC Classifications: H01L

Claim:
1. A method for fabricating a fin field-effect transistor (FinFET), comprising: providing a semiconductor substrate; forming a hard mask layer on the semiconductor substrate, wherein a position of the hard mask layer corresponds to a position of subsequently formed fin; forming a doping region in the semiconductor substrate by using the hard mask layer as a mask to perform an anti-punch-through ion implantation process; forming an anti-punch-through region by performing an annealing process onto the doping region, such that impurity ions in the doping region diffuse into the semiconductor substrate under the hard mask layer; and forming a trench by using the hard mask layer as a mask to etch the semiconductor substrate and the doping region, wherein the semiconductor substrates between the adjacent trenches constitutes a fin.