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. 18, 2018
Filed:
Oct. 08, 2015
Fuji Electric Co., Ltd., Kawasaki-shi, Kanagawa, JP;
Kazumasa Kido, Kawasaki, JP;
Takashi Saitou, Kawasaki, JP;
Kyouhei Fukuda, Kawasaki, JP;
Shinji Tada, Kawasaki, JP;
Fumihiko Momose, Kawasaki, JP;
Yoshitaka Nishimura, Kawasaki, JP;
FUJI ELECTRIC CO., LTD., Kanagawa, JP;
Abstract
A solder joint layer has a structure in which plural fine-grained second crystal sections () precipitate at crystal grain boundaries between first crystal sections () dispersed in a matrix. The first crystal sections () are Sn crystal grains containing tin and antimony in a predetermined proportion. The second crystal sections () are made up of a first portion containing a predetermined proportion of Ag atoms with respect to Sn atoms, or a second portion containing a predetermined proportion of Cu atoms with respect to Sn atoms, or both. The solder joint layer may have third crystal sections () which are crystal grains that contain a predetermined proportion of Sb atoms with respect to Sn atoms. As a result, solder joining is enabled at a low melting point, and a highly reliable solder joint layer having a substantially uniform metal structure can be formed.