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. 05, 2004
Filed:
Dec. 24, 2002
Applicant:
Inventors:
Ryoichi Kurata, Tochigi, JP;
Hoshiro Takahashi, Mouka, JP;
Assignee:
Senju Metal Industry Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B23K 3/102 ; B23K 3/514 ; C22C 9/04 ;
U.S. Cl.
CPC ...
B23K 3/102 ; B23K 3/514 ; C22C 9/04 ;
Abstract
Minute copper balls having a high sphericity which are suitable for use as the cores of copper core solder balls are manufactured by heating small pieces comprising an alloy of 0.5-40 wt % of Zn and a remainder of Cu to at least the melting point of Cu without the pieces contacting each other to give them a spherical shape and cooling the resulting spheres to form solid balls. The minute copper balls which are obtained comprises 0.01-0.5 wt % of Zn and a remainder of Cu and have a spherical shape with a diameter in the range of 50-1000 &mgr;m.