A support substrate includes a first surface and a second surface located above the level of the first surface. Chips are mounted on the first surface. A first insulating film is disposed over each chip. First conductive plugs are connected to the chip extending through each first insulating film. Filler material made of resin filling a space between chips. Wirings are disposed over the first insulating film and the filler material for interconnecting different chips. The second surface, an upper surface of the first insulating film and an upper surface of the filler material are located at the same level.