A Normally-off GaN HFET with p-type GaN gate

ganfetex07.in : A Normally-off GaN HFET with p-type GaN gate

Requires: Blaze
Minimum Versions: Atlas 5.28.1.R

This example demonstrates how to simulate a GaN HFET with p-type GaN gate and is based on the following paper:

"Normally-off AlGaN/GaN HEFT with p-type GaN Gate and AlGaN Buffer"

O. Hilt, A. Knauer, F. Brunner, E. Bahat-Treidel and J. Würfl Ferdinand-Braun-Institut, Leibniz Institut fuer Hoechstfrequenztechnik Gustav-Kirchhoff-Strasse 4, 12489 Berlin, Germany. Proceedings of The 22nd International Symposium on Power Semiconductor Devices & ICs, Hiroshima

While a Schottky-type metal on the AlGaN barrier acts as gate for normally-on HEMTs, a p-type doped semiconductor as gate is able to deplete the transistor channel when unbiased, thus yielding a normally-off device. The simulation of the transfert characteristic reveals a Vt of around 1.25V.

The sub-threshold leakage current drops significantly immediately below the threshold voltage, however the drop slows down to around 4uA/mm at VGS=0V. The leakage current is determined by traps.

The gate current in the on-state (defined as VGS=5V) is around 3uA/mm and thus around 5 orders of magnitude below the drain current. In order to ensure that the charge are present at the interface between p-type GaN, AlGaN and Nitride the PCH.INS REGION=5 parameters of the MODELS statement are used.

The output characteristic shows a negative differential resistance due to lattice heating and simulated by solving the lattice heating equation set by the LAT.TEMP parameter of the MODELS statement. The maximum drain current is about 0.4A/mm.

The Breakdown Voltage of thisdevice is 870V, and the leakage current is controlled by the traps.

To load and run this example, select the Load button in DeckBuild > Examples. This will copy the input file and any support files to your current working directory. Select the Run button in DeckBuild to execute the example.