According to the present invention, a recess portion is formed in a package substrate which is formed of a multilayer organic substrate having a multilayer wiring, and an LSI chip is accommodated within the recess portion. Wiring traces are formed on the upper surface of a resin which seals the LSI chip connected to the multilayer wiring. The wiring traces are connected to terminal wiring traces connected to the multilayer wiring on the front face of the package substrate and to front-face bump electrodes for external connection on the upper surface of the resin. On the back face side of the package substrate, back-face bump electrodes for external connection are formed and connected to the multilayer wiring.