US Patent 7723838 Package structure having semiconductor device embedded within wiring board

In a semiconductor device, via holes are formed around a chip buried in a package, one end of a conductor filled in the via hole is covered with a pad portion exposed to the outside, and a wiring layer connected to the other end of the conductor is formed. The portion (pad portion) of the wiring layer which correspond to the conductor is exposed from a protective film, or an external connection terminal is bonded to the top of the pad portion. Electrode terminals of the chip are connected to the wiring layer, and the opposite surface of the chip is exposed to the outside.