Antonelli, Terry, Stout & Kraus, LLP.
PN-junction gate FET
 A semiconductor device is diclosed which has a PN-junction gate field effect transistor constituting a PN-junction gate with a semiconductor layer of opposite conductivity, an undoped semiconductor layer, and an active layer by depositing sources and drains made of semiconductor layers on the active layer of uniconductivity, depositing an undoped semiconductor layer whose band gap is greater than that of the active layer on the active layer between the opposing end surfaces of the sources and drains, and depositing a semiconductor layer of opposite conductivity on the undoped semiconductor layer away from the sources and drains. In particular, the present invention is effective for an enhancement type PN-junction power FET using compound semiconductors such as GaAs and capable of running with a single power supply and for a semi-conductor device integrating the enhancement type PN-junction power FET and a high-frequency low noise amplifier mono-lithically. 
Hitachi, Ltd.
H H Y
H01L H01L Y10S
inventional inventional additional
Toshiyuki Kenichi Akemi
Usagawa Tominaga Sawada