Abstract
A semiconductor device includes a first nitride semiconductor layer, a second nitride semiconductor layer, a source, a drain, a gate, a plurality of first p-type doped nitride semiconductor islands, a second p-type doped nitride semiconductor island, and a dielectric layer. The second nitride semiconductor layer is provided on the first nitride semiconductor layer and has a band gap larger than that of the first nitride semiconductor layer. The source electrode, the drain electrode and the grid electrode are arranged on the second nitride semiconductor layer. The first p-type doped nitride semiconductor island is disposed on the second nitride semiconductor layer to form a profile protruding from the second nitride semiconductor layer, with a portion of the drain overlying the first p-type doped nitride semiconductor island such that the portion of the drain is conformal with the profile of the first p-type doped nitride semiconductor island. The second p-type doped nitride semiconductor island is disposed between the second nitride semiconductor layer and the gate. The dielectric layer at least covers the gate.