Patent ID: 7075125

Claim:
A power semiconductor device comprising: a first semiconductor layer of non-doped Al X Ga 1âˆ’X N (0â‰¦Xâ‰¦1); a second semiconductor layer of non-doped or n-type Al Y Ga 1âˆ’Y N (0â‰¦Yâ‰¦1, X<Y) disposed on the first semiconductor layer; source and drain electrodes disposed separately from each other, and electrically connected to the second semiconductor layer; a gate electrode disposed on the second semiconductor layer between the source and drain electrodes; an insulating film covering the second semiconductor layer between the gate and drain electrodes; a first field plate electrode disposed on the insulating film and electrically connected to the gate electrode; and a second field plate electrode disposed on the insulating film and electrically connected to the source electrode, wherein the second field plate electrode comprises an intermediate electrode portion interposed between the first field plate electrode and the drain electrode, wherein the insulating film comprises a first insulating film disposed on the second semiconductor layer, and the first field plate electrode and the intermediate electrode portion are disposed on the first insulating film, wherein the second field plate electrode comprises a covering electrode portion that connects the source electrode to the intermediate electrode portion and covers the first field plate electrode through an inter-level insulating film.