Patent ID: 8860090

Claim:
A nitride semiconductor device, comprising: a first semiconductor layer having a first surface and a second surface on a side opposite to the first surface, the first semiconductor layer including Al x Ga 1-x N (0≦x<1); a second semiconductor layer bonded to the first surface, the second semiconductor layer including non-doped or n-type Al y Ga 1-y N (0<y≦1 and x<y); a conductive substrate provided on the second surface side of the first semiconductor layer and electrically connected to the first semiconductor layer; a first electrode electrically connected to a surface of the second semiconductor layer on a side opposite to the first semiconductor layer; a second electrode provided electrically connected to the surface of the second semiconductor layer; a control electrode provided on the surface of the second semiconductor layer between the first electrode and the second electrode; a first terminal; a second terminal; and a third terminal, the first electrode being electrically connected to a drain electrode of a MOSFET formed of Si, the control electrode being electrically connected to a source electrode of the MOSFET, the conductive substrate being electrically connected to a gate electrode of the MOSFET, the first terminal electrically connected to the second electrode, the second terminal electrically connected to the gate electrode of the MOSFET, and the third terminal electrically connected to the source electrode of the MOSFET.