US 12,404,420 B2
Encapsulating material for compression molding and electronic part device
Dongchul Kang, Tokyo (JP); and Seigo Okubo, Tokyo (JP)
Assigned to Resonac Corporation, Tokyo (JP)
Appl. No. 17/642,229
Filed by Showa Denko Materials Co., Ltd., Tokyo (JP)
PCT Filed Sep. 11, 2020, PCT No. PCT/JP2020/034575
§ 371(c)(1), (2) Date Mar. 11, 2022,
PCT Pub. No. WO2021/049645, PCT Pub. Date Mar. 18, 2021.
Claims priority of application No. PCT/JP2019/035934 (WO), filed on Sep. 12, 2019.
Prior Publication US 2022/0315793 A1, Oct. 6, 2022
Int. Cl. C08G 59/18 (2006.01); C08K 9/06 (2006.01); C08K 13/06 (2006.01); C08L 63/00 (2006.01); C09D 7/40 (2018.01); C09D 7/62 (2018.01); C09D 163/00 (2006.01); H01L 23/29 (2006.01); C08L 63/02 (2006.01); C08L 63/04 (2006.01)
CPC C09D 163/00 (2013.01) [C08G 59/18 (2013.01); C08K 9/06 (2013.01); C09D 7/62 (2018.01); C09D 7/68 (2018.01); C09D 7/69 (2018.01); H01L 23/295 (2013.01); C08K 2201/005 (2013.01)] 5 Claims
 
1. An encapsulating material for compression molding, comprising an epoxy resin, a curing agent, and a mixture of a pre-treated first inorganic filler and a second inorganic filler, wherein
in an image obtained by observing, by an ultrasonic flaw detector, a compression-molded body formed by compression-molding the encapsulating material for compression molding on a substrate with a silicon chip interposed, an area of a portion other than dark spots of a region corresponding to the compression-molded body on the silicon chip is 86% or more of an area of the entire region corresponding to the compression-molded body on the silicon chip,
the pre-treated first inorganic filler has been pre-treated with a coupling agent,
a mass reduction ratio of the pre-treated first inorganic filler at 800° C. is in a range of 0.35% to 0.8%,
the pre-treated first inorganic filler has a volume-average particle size of 0.1 μm to 2 μm,
the second inorganic filler has a volume-average particle size larger than 2 μm, and
a ratio of the pre-treated first inorganic filler to the encapsulating material is in a range of 2 mass % to 30 mass %.
 
5. An electronic part device, comprising: an element; and a cured product of the encapsulating material for compression molding of claim 1 that encapsulates the element.