Patent ID: 9117875
Filing Date: 2015-08-25
Classification: H01L

Abstract:
1. A method of forming a FinFET device, comprising: forming a layer of germanium-containing material on a surface of a semiconductor substrate; performing at least one first etching process to form a plurality of initial trenches that extend through said layer of germanium-containing material and into said substrate to an initial depth so as to thereby define an initial fin structure comprised of a portion of said layer of germanium-containing material and a first portion of said substrate; forming sidewall spacers adjacent said initial fin structure; after forming said sidewall spacers, performing a second etching process to extend said initial depth of said initial trenches into said substrate and thereby form a plurality of final trenches having a final depth that is greater than said initial depth and to define a second portion of said substrate positioned under said first portion of said substrate; forming a layer of insulating material so as to over-fill said final trenches; and with said layer of insulating material over-filling said final trenches, performing a thermal anneal process to convert at least a portion of said first or second portions of said substrate into a silicon dioxide isolation material that extends laterally under an entire width of said portion of said layer of germanium-containing material.