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. 02, 2008
Filed:
Aug. 17, 2004
Hiroki Yokoyama, Shunan, JP;
Yasuko Takeda, Shunan, JP;
Reo Yamamoto, Shunan, JP;
Tokuyama Corporation, , JP;
Abstract
A substrate for device bonding includes a substrate having an electrode layer and a solder layer formed on the electrode layer, wherein the solder layer is a Pb-free solder layer which comprises (1) a base metal composed of (i) Sn, (ii) Sn and Au, or (iii) In, (2) at least one metal selected from the group consisting of Bi, In (only in the case where the base metal is Sn, or Sn and Au), Zn, Au (only in the case where the base metal is In) and Sb, and (3) at least one metal selected from the group consisting of Ag, Ni, Fe, Al, Cu and Pt, and the solder layer has a thickness of 1 to 15 μm and a surface roughness (Ra) of not more than 0.11 μm.