Abstract: In a crystalline silicon body a shallow trench insulation is made by etching a groove and filling it with silicon oxide. Ridges of polysilicon are made on the surface of the silicon body by applying a layer of polysilicon and patterning it with a known technique. Spacers of silicon nitride are provided on the side walls of the polysilicon ridges. A first layer of silicon nitride, a second layer of TEOS and a patterned resist layer are applied. The TEOS layer is etched by immersion in a solution of 0.36% HF for 14 minutes. Subsequently, the resist is stripped in H2SO4 or peroxide. The silicon nitride layer is etched by immersion in phosphoric acid of 165° C. for 15 minutes using the TEOS layer as a mask. A titanium layer is applied. Subsequently, the body is rapidly heated to a temperature of 760° C. at which it is kept for 20 seconds. During this rapid thermal treatment titanium silicide is formed at locations where the titanium is in contact with silicon i.e.
Type:
Grant
Filed:
August 6, 1999
Date of Patent:
January 13, 2004
Assignee:
Koninklijke Philips Electronics N.V.
Inventors:
Josephus F. A. M. Guelen, Eric Gerritsen, Walter J. A. De Coster