A substrate (1) and a semiconductor chip (5) are connected by means of flip-chip interconnection. Around connecting pads (3) of the substrate (1) and input/output terminals (10) of the semiconductor chip (5), an underfill material (7) is injected. The underfill material (7) is a composite material of filler and resin in which the maximum particle diameter of the filler is 5 μm or below and whose filler content is 40 to 60 wt %. Also, a first main surface of the substrate (1), which is not covered with the underfill material (7), and the side surfaces of the semiconductor chip (5) are encapsulated with a molding material (8). The molding material (8) is a composite material of filler and resin whose filler content is over 75 wt % and in which the glass transition temperature of the resin is over 180° C. An integrated body of the substrate (1) and the semiconductor chip (5), which are covered with the molding material (8), is thinned from above and below.