Patent ID: 8592866
Filing Date: 2013-11-26
Classification: H01L

Abstract:
1. A transistor comprising: a first semiconductor layer formed on a substrate; a second semiconductor layer formed directly on the first semiconductor layer and has a band gap larger than that of the first semiconductor layer; a control layer selectively formed on the second semiconductor layer and contains p-type impurities; a third semiconductor layer formed between the control layer and the second semiconductor layer; a gate electrode formed on the control layer; and a source electrode and a drain electrode formed on both sides of the control layer, respectively, wherein the third semiconductor layer has a band gap larger than that of the second semiconductor layer, the control layer is apart from the source electrode and the drain electrode, the source electrode and the drain electrode are in direct contact with the third semiconductor layer, the first semiconductor layer, the second semiconductor layer and the control layer are made of nitrogen-containing compound semiconductors, respectively, a length of the control layer is shorter than a length of the third semiconductor layer, a length of the first semiconductor layer and a length of the second semiconductor layer, in a direction perpendicular to a thickness direction, a thickness of the control layer is larger than a thickness of the second semiconductor layer, and a thickness of the second semiconductor layer is larger than a thickness of the third semiconductor layer.