The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 19, 1995
Filed:
Mar. 10, 1994
Michael J Grubisich, San Jose, CA (US);
Christopher S Blair, San Jose, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
A masking method for use in a silicide formation process is disclosed herein which prevents an oxide etching solution from tunneling under a photoresist masking layer and damaging oxide spacers not intended to be etched. This process may be used during the formation of a bipolar or MOS transistor formed in an isolated silicon island. A mask opening used to etch exposed oxide spacer portions is made to not expose any parasitic oxide spacers formed along an edge of the isolated silicon island. In this way, an oxide etch solution is prevented from tunneling along the parasitic oxide spacer and reaching any intersecting oxide spacers not intended to be etched. The desired oxide spacers will thus be intact to properly isolate silicide portions formed over exposed silicon and polysilicon surfaces.