Silicon nitride gate encapsulation by implantation

摘要

A method of forming a FinFET structure which includes forming fins on a semiconductor substrate; forming a gate wrapping around at least one of the fins, the gate having a first surface and an opposing second surface facing the fins; depositing a hard mask on a top of the gate; angle implanting nitrogen into the first and second surfaces of the gate so as to form a nitrogen-containing layer in the gate that is below and in direct contact with the hard mask on top of the gate; forming spacers on the gate and in contact with the nitrogen-containing layer; and epitaxially depositing silicon on the at least one fin so as to form a raised source/drain. Also disclosed is a FinFET structure.

主权项

1. A method of forming a FinFET structure comprising:
forming fins on a semiconductor substrate; forming a gate wrapping around at least one of the fins, the gate having a first surface and an opposing second surface facing the fins; forming a plurality of dummy gates across at least one of the fins such that there is a first dummy gate facing the first surface of the gate and a second dummy gate facing the second surface of the gate, the plurality of dummy gates performing no electrical function; depositing a hard mask on a top of the gate; angle implanting nitrogen into the first and second surfaces of the gate so as to form a nitrogen-containing layer in the gate that is below and in direct contact with the hard mask on top of the gate, wherein angle implanting nitrogen includes angle implanting nitrogen by a gas cluster ion beam process such that a silicon nitride layer is formed below and in direct contact with the hard mask on top of the gate as a direct result of the gas cluster ion beam process; forming spacers on the gate and in contact with the nitrogen-containing layer; and epitaxially depositing silicon on the at least one fin so as to form a raised source/drain.