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:
Oct. 15, 1996
Filed:
Dec. 29, 1992
Applicant:
Inventors:
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ; H01L / ;
U.S. Cl.
CPC ...
437182 ; 437183 ; 437209 ; 2281805 ; 257780 ;
Abstract
A passive state film is formed on a surface of a bonding pad as follows: A silicon substrate 71 is immersed in solution continuously supplied with ozone. Since ozone is continuously supplied, it is possible to maintain the concentration of the dissolved ozone in the solution above a predetermined concentration. Therefore, it is possible to make the speed of formation of the passive state film higher than the speed of fusion of aluminum, which is a main constituent of the bonding pad. Accordingly, it is possible to form a passive state film with no pinholes.