Patent ID: 8629556
Filing Date: 2014-01-14
Classification: H01L

Abstract:
1. A semiconductor device comprising: a substrate; a semiconductor element mounted on the substrate; a bump connecting the substrate and the semiconductor element; and an underfill filling in around the bump, wherein the bump comprises a high-melting-point solder, the high melting point solder having a melting point of 230° C. or more, the underfill comprises a resin material, the resin material having an elastic modulus in the range of 30 MPa to 510 MPa, the substrate has a buildup layer which includes resin-containing insulating layers and conductive interconnection layers, with the insulating layers and conductive interconnection layers being alternately laminated, and each of the conductive interconnection layers being connected by conductive layers, the conductive layers being formed in via holes, the via holes being formed in the insulating layers, a linear expansion coefficient of at least one of the resin-containing insulating layers of the buildup layer in an in-plane direction of the substrate at temperatures between 25° C. and the glass transition temperature of the at least one insulating layer is 35 ppm/° C. or less, and the difference in linear expansion coefficient between the underfill and the bump at temperatures between 25° C. and the glass transition temperature of the at least one insulating layer is 10 ppm/° C. or less.