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.

Date of Patent:
Sep. 22, 2020

Filed:

May. 22, 2019
Applicant:

Senju Metal Industry Co., Ltd., Tokyo, JP;

Inventors:

Hiroki Oshima, Tokyo, JP;

Takeo Saitoh, Tochigi, JP;

Takahiro Nishizaki, Campbell, CA (US);

Tomohisa Kawanago, Tochigi, JP;

Masato Shiratori, Tochigi, JP;

Kaichi Tsuruta, Tochigi, JP;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B23K 35/00 (2006.01); B23K 35/26 (2006.01); B23K 35/30 (2006.01); H05K 3/34 (2006.01); B23K 101/42 (2006.01);
U.S. Cl.
CPC ...
B23K 35/262 (2013.01); B23K 35/3093 (2013.01); H05K 3/3457 (2013.01); B23K 2101/42 (2018.08); H05K 2203/041 (2013.01);
Abstract

A solder ball according to the present invention contains 0.2 to 2.2% by mass of Zn, and a balance of Sn, and has a spherical diameter of 0.1 to 120 μm and a yellowness (b*) in an L*a*b* color system of 2.70 or more and 9.52 or less. An oxide film is formed by performing aging treatment. By producing a solder ball having a yellowness of 2.70 or more and 9.52 or less, it is possible to suppress the growth of a CuSn layer and/or a Cu—Zn(—Sn) layer during joining.


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