Patent ID: 8921999

Claim:
A semiconductor device, comprising: a plurality of die pad sections, each of the plurality of die pad sections having a rear surface; a plurality of semiconductor chips, each of which is arranged on each of the die pad sections; a resin encapsulation portion having a recess portion for exposing at least a portion of the die pad sections, the recess portion having a recess bottom surface and the resin encapsulation portion configured to cover the die pad sections and the semiconductor chips, wherein the rear surfaces of the die pad sections and the recess bottom surface have irregular surfaces having a fine concave-convex shape; and a heat radiation layer arranged in the recess portion, the heat radiation layer being insulating, the recess portion having a recess side surface surrounding the heat radiation layer, the recess side surface spaced apart from the heat radiation layer with a gap left between the heat radiation layer and the recess side surface, the heat radiation layer including an elastic layer exposed toward a direction in which the recess portion is opened, the heat radiation layer directly facing at least a portion of the die pad sections, the elastic layer overlapping with at least a portion of the die pad sections when seen in a thickness direction of the heat radiation layer, wherein the gap is removed after the heat radiation layer being elastically deformed and the heat radiation layer makes direct contact with the recess side surface of the resin encapsulation portion.