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:
May. 14, 1996
Filed:
Oct. 14, 1994
Applicant:
Inventor:
Kenji Kusakabe, Hyogo, JP;
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
437 12 ; 437 10 ;
Abstract
Silicon substrate is provided with silicon single-crystalline wafer, natural oxide film and poly-crystalline silicon film. The thickness of natural oxide film is controlled to be less than 10 .ANG.. Since the thickness of natural oxide film is made less than 10 .ANG., heavy metals travel smoothly from silicon single-crystalline wafer to poly-crystalline silicon film in the process of gettering. In other words, it is possible to enhance gettering effect.