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:
Mar. 26, 1991
Filed:
Oct. 26, 1988
Applicant:
Inventors:
Kiyoaki Tsumura, Itami, JP;
Hitoshi Fujimoto, Itami, JP;
Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B23K / ;
U.S. Cl.
CPC ...
357 67 ; 357 85 ; 228110 ; 228111 ;
Abstract
A structure of an electrode junction for a semiconductor device comprises an insulating film covering the entire surface of a silicon substrate, an aluminum electrode layer which is formed on the insulating film, a copper ball bonded on the electrode layer, and a copper-aluminum alloy layer continuously formed from the copper ball to the aluminum electrode layer. The aluminum layer under the copper ball is not separated from the aluminum layer surrounding the copper ball, so that alloy layer deterioration along the periphery thereof does not cause the electrical resistance to increase. This structure will increase the device life time to the maximum level.