Patent ID: 8264002
Filing Date: 2012-09-11
Classification: H01L

Abstract:
1. A field-effect transistor comprising: a substrate; a first nitride semiconductor layer formed above the substrate; a second nitride semiconductor layer being formed on the first nitride semiconductor layer and having a larger band gap energy than that of the first nitride semiconductor layer; a third nitride semiconductor layer formed on the second nitride semiconductor layer and having a doped layer containing a p-type impurity and a heavily-doped layer containing a p-type impurity at a higher concentration than the doped layer; a gate electrode formed on or above and in contact with the heavily-doped layer of the third nitride semiconductor layer; source and drain electrodes formed on or above the second nitride semiconductor layer so as to be located on both sides of the gate electrode, respectively; and a passivation film for covering at least a side surface of the third nitride semiconductor layer.