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. 19, 1991
Filed:
Jan. 24, 1991
Kanji Otsuka, Higashiyamato, JP;
Masao Kato, Hadano, JP;
Takashi Kumagai, Isehara, JP;
Mitsuo Usami, Ohme, JP;
Shigeo Kuroda, Ohme, JP;
Kunizo Sahara, Nishitama, JP;
Takeo Yamada, Koganei, JP;
Seiji Miyamoto, Fuchuu, JP;
Yuuji Shirai, Kodaira, JP;
Takayuki Okinaga, Akishima, JP;
Kazutoshi Kubo, Akishima, JP;
Hiroshi Tachi, Akishima, JP;
Masayuki Kawashima, Higashimurayama, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi VLSI Engineering Corp., Tokyo, JP;
Abstract
Attempts have been made to increase the number of pins of packages accompanying the trend toward fabricating integrated circuits highly densely and in smaller sizes. The present invention provides technology for improving reliability in fabricating packages of the surface-mounted type that have increased number of pins. That is, when the packages are mounted on the wiring substrate, the lead pins that receive load from the axial direction exhibit bending strength which is smaller than the junction strength of solder at the junction portions. To achieve this object, the lead pins are made of a material having large resiliency such as a fiber-reinforced material, a transformation pseudo elastic material, an ultra-high tension material, or a heat-resistant ultra-high tension material.