Abstract
A nitride-type semiconductor device comprises a substrate, a buffer body, a first nitride semiconductor layer, a shield layer, a second nitride semiconductor layer, a pair of source/drain electrodes, and a gate electrode. The buffer body is disposed on the substrate. The first nitride semiconductor layer is disposed on the buffer body and forms a first interface with the buffer body. The shielding layer comprises a first isolation compound and is interposed between the buffer body and the first nitride semiconductor layer, where the first isolation compound has a band gap larger than a band gap of the buffer body and larger than a band gap of the first nitride semiconductor layer to form at least one electrical isolation region between the buffer body and the first nitride semiconductor layer. The second nitride semiconductor layer is arranged on the first nitride semiconductor layer and has a band gap smaller than a band gap of the first isolation compound and larger than a band gap of the first nitride semiconductor layer. The source/drain electrodes and the gate electrode are arranged on the second nitride semiconductor layer. The gate electrode is between the source/drain electrodes.