METHODS OF FORMING FIN ISOLATION REGIONS ON FINFET SEMICONDUCTOR DEVICES BY IMPLANTATION OF AN OXIDATION-RETARDING MATERIAL

摘要

One illustrative method disclosed herein includes, among other things, forming a fin in a semiconductor substrate, the fin having a lower first section that contains an oxidation-retarding implant region and an upper second section that is substantially free of the oxidation-retarding implant region, forming a sidewall spacer on opposite sides of the upper portion of the fin, forming a first layer of insulating material adjacent the sidewall spacers and the upper second section of the lower portion of the fin, and, with the first layer of insulating material in position, performing a thermal anneal process to convert the portion of the upper second section of the fin that is in contact with the first layer of insulating material into an oxide fin isolation region positioned under the fin above the lower first section of the fin.

主权项

1. A method, comprising:
forming a fin in a semiconductor substrate, said fin comprising a lower portion and an upper portion, wherein said lower portion of said fin has tapered sidewalls and is comprised of a lower first section containing an oxidation-retarding implant region and an upper second section that is substantially free of said oxidation-retarding implant region; forming a sidewall spacer on opposite sides of said upper portion of said fin, wherein said sidewall spacers cover said upper portion of said fin but do not cover said upper second section of said lower portion of said fin; forming a first layer of insulating material adjacent said sidewall spacers and said upper second section of said lower portion of said fin; and with said first layer of insulating material in position, performing a thermal anneal process to convert the portion of said upper second section of said fin that is in contact with said first layer of insulating material into an oxide fin isolation region positioned under said fin above said lower first section of said fin.