Fin field effect transistor and method of forming the same

Abstract

A fin field effect transistor and its forming method, the method includes: providing a semiconductor substrate, the semiconductor substrate has a fin, the side wall of the fin includes a first side wall area and a second side wall located on the first side wall area Sidewall region; forming an interlayer dielectric layer on the semiconductor substrate and the fin, and having an opening exposing part of the sidewall surface and part of the top surface of the fin in the interlayer dielectric layer; forming a target work function on the sidewall and bottom of the opening The target work function layer includes a first target region covering only the first sidewall region and a second target region covering only the second sidewall region, the second target region and the target work function layer located on the top surface of the fin Doped with modifying ions, the first target region has a first effective work function value, the second target region, and the target work function layer on the top surface of the fin have a second effective work function value, the first effective work function value less than the second effective work function value. The method improves the electrical performance of the FinFET.

Description

technical field [0001] The invention relates to the field of semiconductor manufacturing, in particular to a fin field effect transistor and a forming method thereof. Background technique [0002] MOS (Metal-Oxide-Semiconductor) transistors are one of the most important components in modern integrated circuits. The basic structure of the MOS transistor includes: a semiconductor substrate; a gate structure located on the surface of the semiconductor substrate, and the gate structure includes: a gate dielectric layer located on the surface of the semiconductor substrate and a gate electrode layer located on the surface of the gate dielectric layer; The source and drain doped regions in the semiconductor substrate on both sides of the pole structure. [0003] With the development of semiconductor technology, the ability of the traditional planar MOS transistor to control the channel current becomes weaker, resulting in serious leakage current. Fin Field Effect Transistor (Fin...

AI Technical Summary

Problems solved by technology

[0004] However, the electrical performance of fin field effect transistors in the prior art still needs to be improved

Images