Methods of forming bulk FinFET devices with replacement gates so as to reduce punch through leakage currents

摘要

One illustrative method disclosed herein includes forming a plurality of spaced-apart trenches in a semiconducting substrate to thereby define a fin structure for the device, forming a local isolation region within each of the trenches, forming a sacrificial gate structure on the fin structure, wherein the sacrificial gate structure comprises at least a sacrificial gate electrode, and forming a layer of insulating material above the fin structure and within the trench above the local isolation region. In this example, the method further includes performing at least one etching process to remove the sacrificial gate structure to thereby define a gate cavity, after removing the sacrificial gate structure, performing at least one etching process to form a recess in the local isolation region, and forming a replacement gate structure that is positioned in the recess in the local isolation region and in the gate cavity.

主权项

1. A method of forming a FinFET device, comprising:
forming a plurality of spaced-apart trenches in a semiconducting substrate, said trenches defining a fin structure for said device, said fin structure having an upper surface; forming a local isolation region within each of said trenches, said local isolation region having an upper surface that is positioned below said upper surface of said fin structure; after forming said local isolation regions, forming a sacrificial gate structure on said fin structure, wherein forming said sacrificial gate structure comprises forming a gate insulation layer on sidewall surfaces and said upper surface of said fin and forming a sacrificial gate electrode above said gate insulation layer; forming a layer of insulating material above said fin structure and within said trench above said local isolation region; performing at least one etching process to remove said sacrificial gate structure to thereby define a gate cavity; after removing said sacrificial gate structure, performing at least one etching process to form a recess in said local isolation region, wherein sidewalls of said recess are substantially aligned with sidewalls of said gate cavity; and forming a replacement gate structure that is positioned in said recess in said local isolation region and in said gate cavity.