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. 09, 2003
Filed:
Dec. 02, 1999
Applicant:
Inventors:
Hitoshi Iwata, Aichi, JP;
Makoto Murate, Aichi, JP;
Assignee:
Kabushiki Kaisha Tokai Rika Denki Seisakusho, Aichi, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 2/100 ;
U.S. Cl.
CPC ...
H01L 2/100 ;
Abstract
An epitaxial growth layer, an oxide film, and a passivation film are formed on a silicon substrate. Except for an opening formed on a part of the passivation film, the upper surface of the passivation film is covered with a metal protective film made of tungsten (W). With the silicon substrate immersed in a high-concentration hydrofluoric aqueous solution, anodization is performed with the silicon substrate as an anode and the metal protective film as a counter electrode.