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:
Jan. 14, 1986
Filed:
Dec. 08, 1981
Applicant:
Inventors:
Kazumoto Homma, Sagamihara, JP;
Masaharu Watanabe, Yokosuka, JP;
Assignees:
Toshiba Ceramics Co., Ltd., Tokyo, JP;
Tokyo Shibaura Denki Kabushiki Kaisha, Kawasaki, JP;
Primary Examiner:
Int. Cl.
CPC ...
C30B / ;
U.S. Cl.
CPC ...
1566 / ; 156D / ;
Abstract
A method of producing a semiconductor device comprising a semiconductor substrate exhibiting defect density of 10.sup.5 /cm.sup.2 or more when the central portion of the substrate is observed through an optical microscope after the substrate is heat-treated at 1,050.degree. C. for 18 hours and etched along a section thereof across the thickness thereof.