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. 14, 1991
Filed:
Jul. 31, 1989
Koichi Machida, Yokohama, JP;
Mikio Kitahara, Yokohama, JP;
Takayuki Kubo, Yokohama, JP;
Motoyuki Torikai, Yokohama, JP;
Koutarou Asahina, Kamakura, JP;
Mitsui Toatsu Chemicals, Inc., Tokyo, JP;
Abstract
A resin composition for sealing semiconductors which comprises (a) an epoxy resin, (b) a hardening agent, (c) an inorganic filler and (d) a polymaleimide having a specific structure is herein provided. Preferably, the resin composition comprises, as all of or a part of the epoxy resin, a modified epoxy resin composed of (i) a graft polymer of an epoxy resin and a vinyl polymer and (ii) a silicone polymer in an oily state or as particles having an average particle size of not more than 1.0 micron, which are uniformly dispersed in the graft polymer. The resin composition for sealing semiconductors exhibits a low thermal expansion coefficient and a low elastic modulus, generates low stress when thermal shock is applied thereto and exhibits high heat resistance during soldering even after moisture absorption. Therefore, if the composition is used to seal semiconductor devices on a large scale having degree of integration or small-sized, thin semiconductors such as flat packages, these semiconductors provide high reliability.