A semiconductor device 50 is constructed to connect Al electrode pads 20 and rewiring patterns 52 via through electrodes 56 and flip-chip connect the rewiring patterns 52 of a semiconductor element 14 and wiring patterns 24 on a wiring substrate 12 via solder bumps 58. A device forming layer 18 and a plurality of Al electrode pads 20 are formed on an upper surface of the semiconductor element 14. Through holes 54 passing through the semiconductor element 14 are provided between the Al electrode pads 20 and the rewiring patterns 52 by the dry etching, and through electrodes 56 are formed in insides of the through holes 54 by the Cu plating. The device forming layer 18 is arranged on an upper surface of the semiconductor element 14 to make a light reception and a light emission easily.