Abstract
A semiconductor device includes a first nitrogen-based semiconductor layer, a second nitrogen-based semiconductor layer, a pair of first electrodes, a second electrode, a doped nitrogen-based semiconductor layer, and a pair of gate electrodes. The second nitrogen-based semiconductor layer is disposed on the first nitrogen-based semiconductor layer. The first and second nitrogen-based semiconductor layers collectively have an active portion and an electrically insulating portion, the electrically insulating portion being non-semiconductive and surrounding the active portion to form an interface therebetween. The first electrode is disposed on the second nitrogen-based semiconductor layer. The second electrode is disposed over the second nitrogen-based semiconductor layer and between the first electrodes. A doped nitrogen-based semiconductor layer is disposed over the second nitrogen-based semiconductor layer, between the first electrodes, and around the second electrode. A gate electrode is disposed on the doped nitrogen-based semiconductor layer and on an opposite side of the second electrode.