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Title: Power device breakdown mechanism and characterization: review and perspective
Abstract Breakdown voltage (BV) is arguably one of the most critical parameters for power devices. While avalanche breakdown is prevailing in silicon and silicon carbide devices, it is lacking in many wide bandgap (WBG) and ultra-wide bandgap (UWBG) devices, such as the gallium nitride high electron mobility transistor and existing UWBG devices, due to the deployment of junction-less device structures or the inherent material challenges of forming p-n junctions. This paper starts with a survey of avalanche and non-avalanche breakdown mechanisms in WBG and UWBG devices, followed by the distinction between the static and dynamic BV. Various BV characterization methods, including the static and pulse I – V sweep, unclamped and clamped inductive switching, as well as continuous overvoltage switching, are comparatively introduced. The device physics behind the time- and frequency-dependent BV as well as the enabling device structures for avalanche breakdown are also discussed. The paper concludes by identifying research gaps for understanding the breakdown of WBG and UWBG power devices.  more » « less
Award ID(s):
2036740 2202620 2045001 2100504
PAR ID:
10396738
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Japanese Journal of Applied Physics
Volume:
62
Issue:
SC
ISSN:
0021-4922
Page Range / eLocation ID:
SC0806
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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