GALLIUM NITRIDE based heterojunction field-effect transistors (HFETs) show great promise for high-frequency, high-power, and high-temperature applications. Many researchers have fabricated AlGaN/GaN HFETs with very impressive results, including a device with a current handling capability of 1.25 A/mm on SiC substrates[2]. Assuming a sheet charge density of 1.4×1013 cm−2, and a saturation veloci...

We have reported the results of prototyping an inverter as one of the GaN-based power supplies. The inverter comprised a DC converter circuit and AC inverter circuit, and the operating output power was 50 W, reaching a maximum power of 200 W 6) . However, the devices used in these inverters were of the normally-on type. In this work, normally-off type devices were fabricated making full use of ...

AlGaN–GaN heterostructures with different Al concentrations (20, 27, and 35%) were grown by metal-organic vapor phase epitaxy (MOVPE) on sapphire substrates. Ti–Al–Ti–Au ohmic contact optimization was investigated at different temperatures and annealing time. Heterojunction field effect transistors (HFET) with a gate length of 0.25 m were fabricated. Low contact resistances of 0.2, 0.26, and 0....

In this paper recent developments of RF front-end system based on the active integrated antenna design concepts are presented. Thanks to the enhancements in the design of special antennas working as radiator as well as providing the other circuit functionalities, the antenna-integrated RF front ends have been capable of improving the circuit-efficiency and compactness. These enhancements are il...

We have profiled the parasitic source and drain resistances versus current in recessed-gate HFET's with heavily-doped caps, using an InAIAs/n+-InP HFET as a vehicle. We observe a dramatic reduction in the parasitic resistances at moderate-to-high currents as significant current passes through the cap. Consequently, we note very little dependence in gm on the length of the extrinsic gate-source ...

In the 21st century, environmental measures such as reducing CO2 emissions have been demanded in energy development. Si switching devices are generally used as electric power converting devices. To reduce power loss, the density of Si device integration has become satisfactorily high. As a result, the on-state resistance of a Si metal oxide semiconductor field effect transistor (MOSFET) reached...

The operating principle and noise performance in AlGaN/GaN HFETs has been studied. In particular, it has been demonstrated that substrate material selection plays a great role in device performance for application point of view. Polarization induced surface states plays key role in formation of 2 DEG. Performance parameters study of device is related to noise study in devices because low freque...