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. 11, 2004
Filed:
May. 02, 2002
Sumitomo Bakelite Company Limited, Tokyo, JP;
Abstract
The present invention provides a process for producing an epoxy resin composition for semiconductor encapsulation which, when used in encapsulation of a semiconductor chip, can minimize voids appearing in the semiconductor device obtained. That is, the present invention provides a process for producing an epoxy resin composition for semiconductor encapsulation, which comprises premixing raw materials containing at least an epoxy resin, a phenolic resin, a curing accelerator and an inorganic filler, then grinding the resulting premix using a grinder to obtain a ground material having such a particle size distribution that particles having particle diameters of 250 &mgr;m or more are 10% by weight or less, particles having particle diameters of 150 &mgr;m to less than 250 &mgr;m are 15% by weight or less and particles having particle diameters of less than 150 &mgr;m are 75% by weight or more, and melt-kneading the ground material under a reduced pressure, or melt-kneading the ground material and then exposing the resulting molten material to a reduced pressure.