Simulating RF Performance of Proton Irradiated AlGaN/GaN High Electron Mobility Transistors (HEMT)s

Abstract

AlGaN/GaN High Electron Mobility Transistors (HEMTS) subjected to proton irradiation of fluence up to 1014 cm-2 were simulated to observe the impact on small signal and RF characteristics. While a lot of work has covered dc degradation of HEMTs, very few studies exist which focus exclusively on RF degradation despite their high frequency applications. This work establishes a simulation framework capable of frequency domain device simulation up to 10 GHz. The role of defects generated by proton irradiation will be studied by carrying out low frequency transconductance simulation and current gain frequency sweeps to examine degradation of cut-off frequency. The primary objective will be to understand the role of partially ionized donor traps near the AlGaN/GaN interface and how their bias dependence and capture time constants may significantly impact cut-off frequency and current gain estimations at high frequencies.

Effects of Gd2O3 Gate Dielectric on Proton-Irradiated AlGaN/GaN HEMTs

“…Studies of irradiation effects on AlGaN/GaN based HEMTs and MOS-HEMTs (using Al2O3 [13], NbAlO [14], SiO2 [15], MgO or Sc2O3 [16]) have been explored using different energies and fluences, experimentally [6,7] and by simulation [21]- [23]. For instance, the Al2O3/AlGaN/GaN MOS-HEMTs showed over 50% decrease in maximum drain current after 5×10 15 cm -2 fluence irradiation with 5 MeV protons [13].…”

(Invited) Simulation of the Effects of As-Grown Defects on GaN-Based Power HEMTs

“…In this work, we attempt to simulate drain lag transient performance of AlGaN/GaN HEMTs by incorporating donor and acceptor-like point defects using FLOODS TCAD. In a previous study of radiation effects on the steady-state and RF performance of AlGaN/GaN HEMTs using FLOODS, several key conclusions were reached (7,13,14). First, it is important to consider both acceptor and donor like defects, in a GaN bulk that necessitates the presence of a net negative charge to allow appropriate switching off.…”