Patent ID: 8338860

Claim:
A heterostructure field effect transistor (HFET) gallium nitride (GaN) semiconductor power device comprising: a hetero-junction structure comprises a first semiconductor layer interfacing a second semiconductor layer of two different band gaps thus generating an interface layer as a two-dimensional electron gas (2DEG) layer; a source electrode and a drain electrode disposed on two opposite sides of a gate electrode disposed on top of said hetero-junction structure for controlling a current flow between said source and drain electrodes in said 2DEG layer; said hetero-junction structure comprises said first and second semiconductor lavers constituting a rectangular block with a longitudinal direction extending from the source electrode to the drain electrode; a floating gate located between said gate electrode and hetero-junction structure, wherein said gate electrode is insulated from said floating gate with an insulation layer and wherein said floating gate is disposed above and padded with a thin insulation layer from said hetero-junction structure and wherein said floating gate is charged for continuously applying a voltage to said 2DEG layer to pinch off said current flowing in said 2DEG layer between said source and drain electrodes whereby the HFET semiconductor power device is a normally off device; and the gate electrode and the floating gate with the insulation layers constituting a wrap-around gate wrapping around at middle segment of said rectangular block around sidewalls and a top surface of said middle segment of said rectangular block to control the 2DEG layer venerated between the first and second semiconductor layers.