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:
Dec. 19, 1995
Filed:
Jan. 19, 1993
Masahide Harada, Yokohamashi, JP;
Akihiro Ando, Yokohama, JP;
Ryohei Satoh, Yokohama, JP;
Akira Yabushita, Yokohama, JP;
Naoya Kanda, Yokosuka, JP;
Kazuhiko Horikoshi, Kawasaki, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A solder bonding metal layer which is formed on a circuit board comprises a metal layer having a mixture of first metal which is easily wetted with metals constituting the solder and which easily forms alloy or intermetallic compounds and of second metal which is not wetted easily with the above solder and not melted. In this case, a concentration gradient that the concentration of the first metal is high on the bonding surface may be formed in the metal layer. A circuit board having a solder bonding metal layer which keeps good bonding even after many times of repairs and improves the reliability is realized.