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:
Nov. 29, 2005
Filed:
Jan. 14, 2002
Masamoto Tago, Tokyo, JP;
Tomohiro Nishiyama, Tokyo, JP;
Tetuya Tao, Tokyo, JP;
Kaoru Mikagi, Tokyo, JP;
Masamoto Tago, Tokyo, JP;
Tomohiro Nishiyama, Tokyo, JP;
Tetuya Tao, Tokyo, JP;
Kaoru Mikagi, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A highly reliable semiconductor chip electrode structure allowing control of interface reaction of bonding sections even in the case of using two- or three-element solder used conventionally is disclosed. A solder alloy making layer for preventing dissolving and diffusion of tin into tin-based lead free solder is thinly formed on a UBM layer. The tin-based solder is supplied in solder paste or solder ball form. A combined solder alloy layer composed of a combination of intermetallic compounds, one of tin and the solder alloy making layer, and one of tin and the UBM layer, is formed by heating and melting.