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:
May. 17, 2016
Filed:
Jul. 25, 2014
Jx Nippon Mining & Metals Corporation, Tokyo, JP;
Yuichiro Shindo, Ibaraki, JP;
Kouichi Takemoto, Ibaraki, JP;
JX Nippon Mining & Metals Corporation, Tokyo, JP;
Abstract
High purity tin and tin alloy are provided in which the respective contents of U and Th are 5 ppb or less, the respective contents of Pb and Bi are 1 ppm or less, and the purity is 5N or higher, provided that this excludes the gas components of O, C, N, H, S and P. A cast ingot of the tin or alloy has an α ray count of 0.001 cph/cmor less. Since recent semiconductor devices are densified and of large capacity, there is risk of a soft error occurring due to α ray from materials in the vicinity of the semiconductor chip. Thus, there are demands for purifying soldering material used in the vicinity of semiconductor devices, and materials with fewer α rays. The disclosed tin, alloy, and method reduce α dose of tin so as to be adaptable as the foregoing material.