Tuesday, March 06, 2012

US Patent 8129247 - Omega shaped nanowire FET


This patent from IBM teaches a method to improve the doping characteristics of nanowires used as the channels of field effect transistors by using epitaxial growth rather than ion implantation. Claim 1 reads:

1. A method for forming a nanowire field effect transistor (FET) device, the method comprising:

forming a nanowire on a semiconductor substrate;

forming a first gate structure on a first portion of the nanowire;

forming a first protective spacer adjacent to sidewalls of the first gate structure and over portions of the nanowire extending from the first gate structure;

removing exposed portions of the nanowire left unprotected by the first spacer; and

epitaxially growing a doped semiconductor material from exposed cross sections of the nanowire to form a first source region and a first drain region.