AlGaN/GaN/AlN 'Buffer-Free' High Voltage MISHEMTs with Si-rich and Stoichiometric SiNxFirst Passivation
Paper in proceeding, 2022

Buffer-free' AlGaN/GaN/AlN high electron mobility transistors (HEMTs) with a thin GaN channel layer and a thin AlN nucleation layer grown on a semi-insulating SiC substrate are presented. Si-rich and a stoichiometric low-pressure chemical vapor deposition (LPCVD) SiNx first passivation were employed to study the impact of stoichiometry on off-state leakage currents in GaN-based metal-insulator-semiconductor (MIS)HEMTs. Nitrogen implantation isolation, SiOx second passivation, gate and source field plates were utilized. Off-state drain leakage current was reduced 2-3 orders of magnitude by depositing a stoichiometric instead of a Si-rich SiNx passivation. The gate leakage current was suppressed below 10nA/mm until breakdown. A destructive breakdown voltage of 1742V and 1532V was measured for the MISHEMTs with Si-rich and stoichiometric SiNx passivation, respectively. This demonstrates how high voltage, low leakage MISHEMTs can be achieved using a 'buffer-free' heterostructure by optimizing the first passivation stoichiometry.

SiN passivation x

'buffer-free'

GaN-on-SiC

MISHEMT

AlGaN/GaN/AlN

high voltage

Author

Björn Hult

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

Mattias Thorsell

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

J. T. Chen

SweGaN AB

Niklas Rorsman

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

2022 Compound Semiconductor Week, CSW 2022


9781665453400 (ISBN)

2022 Compound Semiconductor Week, CSW 2022
Ann Arbor, USA,

Subject Categories

Materials Chemistry

Other Electrical Engineering, Electronic Engineering, Information Engineering

Condensed Matter Physics

DOI

10.1109/CSW55288.2022.9930464

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