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:
Nov. 11, 1986
Filed:
May. 02, 1985
Jan G Dil, Eindhoven, NL;
Johan W Bartsen, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
The method of the present invention involves the forming of a depression with sidewalls extending below a first oxidation mask provided on a surface of a silicon body. Subsequently, after the sidewalls of the depression have been provided with a second oxidation mask, an oxidation treatment is carried out. According to the invention, the depression is provided in such a manner that the sidewalls of the depression are flat and form an angle of 25.degree. to 45.degree. with the original surface of the silicon body. The second oxidation mask is formed by a 5 to 50 nm thick layer of silicon nitride or silicon oxinitride applied directly or separated from the surface by a layer of silicon oxide having a thickness of less than 5 nm. This leads to a very flat structure.