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:
Aug. 28, 1990
Filed:
Dec. 11, 1989
Paulus A van der Plas, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
A method of manufacturing a semiconductor device, in which on a surface (1) of a silicon wafer (2) an oxidation mask (3) is locally provided, whereupon the wafer is subjected to an oxidation treatment, in which a layer of field oxide (8) is formed. In order to compensate for thickness losses during further processing steps, a layer of field oxide (8) has to be formed having a thickness exceeding a desired isolation thickness. This initial thickness is realized according to the invention in such a manner that a layer is formed having a thickness which is larger than the initial thickness, whereupon in a plasma with reactive ions this layer is etched back to the desired initial thickness. In the layer thus formed, having the desired initial thickness, the layer of field oxide is prevented from locally being etched in an etching solution (such as the hydrofluoride solution) at a higher rate during further processing steps.