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. 17, 2002
Filed:
Feb. 01, 2001
Noriyuki Takasaki, Tochigi, JP;
Kenji Takayama, Musashimurayama, JP;
Yoshiyuki Anai, Utsunomiya, JP;
Sumitomo Bakelite Company Limited, Tokyo, JP;
Abstract
The present invention provides a process for producing an epoxy resin molding material for semiconductor encapsulation, which is very low in voids generation; a molding material produced by the process; and a semiconductor device obtained by encapsulation with the molding material. That is, the present invention provides a process for producing an epoxy resin molding material for semiconductor encapsulation, which comprises premixing a composition containing at least an epoxy resin, a phenolic resin and an inorganic filler, then subjecting the resulting mixture to grinding by a grinder to obtain a powder having such a particle size distribution that the amount of particles having particle diameters of 250 &mgr;m or more is 10% by weight or less, the amount of particles having particle diameters of 150 &mgr;m to less than 250 &mgr;m is 15% by weight or less, and the amount of particles having particle diameters of less than 150 &mgr;m is 75% by weight or more, and thereafter subjecting the powder to melt kneading; a molding material produced by the process; and a semiconductor device obtained by encapsulation with the molding material.