A semiclassical 2D ensemble Monte Carlo simulator is used to perform a physical microscopic analysis of kink effect in InAs/AlSb High Electron Mobility Transistors (HEMTs). Due to the small bandgap of InAs, these devices are very susceptible to suffer impact ionization processes, with the subsequent hole transport through the structure, both implicated in the kink effect. The results indicate t...

Significant progress has been achieved in making larger (2 inch) 4H-SiC substrates with much lower micropipe defect densities. With the recent availability of semi-insulating 4H-SiC substrates, the demonstration of impressive microwave power results have been made possible both in SiC MESFETs and in GaN/AlGaN HEMTs grown on these substrates. SiC MESFETs have achieved RF power densities of 4.6 W...

Heterostructure field-effect transistors (HFETs) composed of antimonide-based compound semiconductor (ABCS) materials have intrinsic performance advantages due to the attractive electron and hole transport properties, narrow bandgaps, low ohmic contact resistances, and unique band-lineup design flexibility within this material system. These advantages can be particularly exploited in applicatio...

1. Introduction The surface trap of AlGaN/GaN high electron mobility transistors (HEMTs) can cause current collapse phenomenon which is the most serious limiting factor of the device's output power at high frequency operation. The surface passivation is a key step to reduce surface state effects and the quality of surface passivation film is very important [1]. Silicon nitride (SiNX) is widely ...

We report a successful application of atomic layer deposition (ALD) aluminum oxide as a passivation layer to gallium nitride high electron-mobility transistors (HEMTs). This new passivation process results in 8%–10% higher dc maximum drain current and maximum extrinsic transconductance, about one order of magnitude lower drain current in the subthreshold region, 10%–20% higher pulsed-I V drain ...

In this paper, we review our recent results in developing gas sensors for hydrogen using various device structures, including ZnO nanowires and GaN High Electron Mobility Transistors (HEMTs). ZnO nanowires are particularly interesting because they have a large surface area to volume ratio, which will improve sensitivity, and because they operate at low current levels, will have low power requir...

This work addresses the enormous efficiency and linearity potential of optimized AlGaN/GaN high-electron mobility transistors (HEMT) in conventional Doherty linear base-station amplifiers at 2.7 GHz. Supported by physical device simulation, the work further elaborates on the use of AlGaN/GaN HEMTs in high-speed current-switch-mode classD (CMCD)/class-S MMICs for data rates of up to 8 Gbit/s equ...

Ultrahigh-speed circuit applications of resonant-tunneling diodes (RTDs) have been developed. The key points are the utilization of the edge-triggered and latching properties arising from negative differential resistance of the RTD, and the combination of RTDs and high electron mobility transistors (HEMTs). High-speed and low power operation of various flip-flop (FF) circuits monolithically int...

Gate degradation in high electron mobility transistors (HEMTs) under OFF-state stress results from the high electric field near the gate edge. We investigate the evolution of this field over time in AlGaN/ GaN HEMTs upon OFF-state stress using a combination of electroluminescence (EL) microscopy and spectroscopy. EL analysis suggests that the electric field at the sites of generated surface def...

In this paper, a half-bridge gate driver with adaptive output current for GaN HEMTs is introduced. The drive of the adapted to load HEMTs, by adjusting W/L size transistors. rise time achieved be basically constant adjustment different load, so noise can effectively immunized and working efficiency improved. Based on proposed circuit, designed implemented in 180nm BCD process. Tested results sh...