Patent ID: 6376286
Filing Date: 2002-04-23
Classification: H01L

Abstract:
A method of forming a field effect transistor on a semiconductor substrate, comprising of:a) etching an insulating trench around the perimeter of an active region of said transistor to isolate the active region from other structures on said substrate; b) etching an insulating undercut in the bottom of the insulating trench to isolate at least a portion of the bottom surface of the active region from the substrate; and c) doping portion of the active region to from each of a source region and a drain region on opposing side of a central channel region, wherein the insulating undercut isolates at least a portion of both the source region and the drain region from the semiconductor substrate, and wherein the undercut isolates at least a portion of the central channel region from the semiconductor substrate, the undercut extending under the central channel region in a direction from the source region to the drain region; wherein the etching the undercut and the doping from a conductive bridge between the central channel region and the substrate.