The switching performance of unpackaged vertical geometry NiO/ β -Ga 2 O 3 rectifiers with a reverse breakdown voltage of 1.76 kV (0.1 cm diameter, 7.85 × 10 −3 cm 2 area) and an absolute forward current of 1.9 A fabricated on 20 μ m thick epitaxial β -Ga 2 O 3 drift layers and a double layer of NiO to optimize breakdown and contact resistance was measured with an inductive load test circuit. The Baliga figure-of-merit of the devices was 261 MW.cm −2 , with differential on-state resistance of 11.86 mΩ.cm 2 . The recovery characteristics for these rectifiers switching from forward current of 1 A to reverse off-state voltage of −550 V showed a measurement-parasitic-limited recovery time (t rr ) of 101 ns, with a peak current value of 1.4 A for switching from 640 V. The reverse recovery time was limited by extrinsic parasitic and thus does not represent the intrinsic device characteristics. There was no significant dependence of t rr on switching voltage or forward current.
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1 mm 2 , 3.6 kV, 4.8 A NiO/Ga 2 O 3 Heterojunction Rectifiers
Large area (1 mm2) vertical NiO/
- PAR ID:
- 10438046
- Publisher / Repository:
- The Electrochemical Society
- Date Published:
- Journal Name:
- ECS Journal of Solid State Science and Technology
- Volume:
- 12
- Issue:
- 8
- ISSN:
- 2162-8769
- Page Range / eLocation ID:
- Article No. 085001
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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