The semiconductor device and the multilayer wiring substrate, and methods for their preparation

A semiconductor device includes a multilayer wiring board and a semiconductor chip mounted on the multilayer wiring board. Electrode pads of the semiconductor chip include: first electrode pads including electrode pads respectively disposed in the vicinity of corners of the back surface of the semiconductor chip; and second electrode pads other than the first electrode pads. Connection pads of the multilayer wiring board include: first connection pads connected to the first electrode pads via bumps; and second connection pads connected to the second electrode pads via bumps. The first connection pads are supported by a first insulating region made of a thermoplastic resin, and the second connection pads are supported by a second insulating region made of a thermosetting resin.