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High-Voltage AlGaN/GaN High-Electron-Mobility Transistors Using Thermal Oxidation for NiOx Passivation

  • Kim, Minki ;
  • Seok, Ogyun ;
  • Han, Min-Koo ;
  • Ha, Min-Woo
  • Received : 2012.12.21
  • Accepted : 2013.04.03
  • Published : 2013.09.01

Abstract

We proposed AlGaN/GaN high-electron-mobility transistors (HEMTs) using thermal oxidation for NiOx passivation. Auger electron spectroscopy, secondary ion mass spectroscopy, and pulsed I-V were used to study oxidation features. The oxidation process diffused Ni and O into the AlGaN barrier and formed NiOx on the surface. The breakdown voltage of the proposed device was 1520 V while that of the conventional device was 300 V. The gate leakage current of the proposed device was 3.5 ${\mu}A/mm$ and that of the conventional device was 1116.7 ${\mu}A/mm$. The conventional device exhibited similar current in the gate-and-drain-pulsed I-V and its drain-pulsed counterpart. The gate-and-drain-pulsed current of the proposed device was about 56 % of the drain-pulsed current. This indicated that the oxidation process may form deep states having a low emission current, which then suppresses the leakage current. Our results suggest that the proposed process is suitable for achieving high breakdown voltages in the GaN-based devices.

Keywords

AlGaN;GaN;HEMT;Oxidation;Nickel oxide

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Cited by

  1. Achievement of normally-off AlGaN/GaN high-electron mobility transistor with p-NiOx capping layer by sputtering and post-annealing vol.401, 2017, https://doi.org/10.1016/j.apsusc.2017.01.032
  2. Pulse-Mode Dynamic Ron Measurement of Large-Scale High-Power AlGaN/GaN HFET vol.39, pp.2, 2017, https://doi.org/10.4218/etrij.17.0116.0385
  3. Electrical Characteristics of Enhancement-Mode n-Channel Vertical GaN MOSFETs and the Effects of Sidewall Slope vol.10, pp.3, 2015, https://doi.org/10.5370/JEET.2015.10.3.1131

Acknowledgement

Supported by : KETEP