Stacked semiconductor device

A stacked semiconductor device, comprising:

• a first semiconductor device unit comprising a first wiring substrate, at least one semiconductor device mounted on said first wiring substrate, and a first external connection terminal provided at a surface opposite to a surface where said semiconductor device is mounted of said first wiring substrate and a position facing a position at which said semiconductor device is mounted, and in the vicinity of said position facing said position at which said semiconductor device is mounted,
• a second wiring substrate that is prepared below said first semiconductor device unit,
• a second semiconductor device unit comprising at least one semiconductor device that is mounted on said second wiring substrate, and a connection electrode formed on a surface of said second wiring substrate, said surface facing said first semiconductor device unit,
• a third wiring, comprising a circuit board of said third wiring substrate arranged between said first semiconductor device unit and said second semiconductor device unit, a first conductive member for electrically connecting said circuit board and said connection electrode, a second conductive member that is formed corresponding to a form position of said first external connection terminal, said second conductive member being electrically connected to said first external connection terminal, and a third conductive member for electrically connecting said first conductive member and said second conductive member.