Patent ID: 9646885
Date: 2017-05-09
CPC Classifications: H01L

Claim:
1. A method for preventing epitaxial growth in a semiconductor device comprising: cutting fins of FinFET structure to form a set of exposed fin ends, each fin having a bottom face facing a substrate, a top face opposite the bottom face and a pair of parallel side faces, each exposed fin end orthogonally disposed between a respective pair of parallel side faces and between a respective top face and a respective bottom face; performing a plasma nitridation process on the set of exposed fin ends to produce a set of nitride layer covered fin ends of the FinFET structure; depositing a layer of silicon oxide on the FinFET structure including in a well area of the FinFET structure; performing a chemical mechanical polishing step to remove excess silicon oxide from the layer of silicon oxide outside the well area of the FinFET structure; etching silicon oxide areas from the layer of silicon oxide around the FinFET structure to reveal a portion of the parallel side faces of the fins for further processing; and wherein the nitride layer at the exposed fin ends prevents epitaxial growth at the set of nitride layer covered fin ends of the FinFET structure.