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:
Feb. 13, 1990
Filed:
Apr. 24, 1989
F J Robinson, Scottsdale, AZ (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A new method is used to fabricate an isolation trench to prevent spurious epitaxial growth at the top edge of the trench opening and at pin holes in oxide over the active area. The method involves etching a deep trench into a semiconductor wafer that is patterned with a mask oxide layer, and then depositing a low temperature oxide, followed by growing a thermal oxide layer under the mask oxide and in the trench. When the oxide at the bottom of the trench is removed to provide a seed for the growth of selective epitaxial silicon, an oxide layer thick enough to leave a protective coating over the active area and at the trench opening is provided which prevents spruious epitaxial silicon growth.