Patent ID: 8164117
Filing Date: 2012-04-24
Classification: H01L

Abstract:
1. A nitride semiconductor device comprising: a main semiconductor region comprising a first nitride semiconductor layer having a first band gap, and a second nitride semiconductor layer having a second band gap larger than the first band gap, a heterojunction being formed between the first nitride semiconductor layer and the second nitride semiconductor layer such that a two-dimensional electron gas layer can be caused inside the first nitride semiconductor layer based on the heterojunction; a source electrode formed on the main semiconductor region; a drain electrode formed on the main semiconductor region and separated from the source electrode; a third nitride semiconductor layer formed on the first nitride semiconductor layer and between the source electrode and the drain electrode; a fourth nitride semiconductor layer formed on the third nitride semiconductor layer and having p-type conductivity; and a gate electrode formed on the fourth nitride semiconductor layer, wherein the third nitride semiconductor layer has a third band gap smaller than the first band gap.