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We report the effect of extended duration electron beam exposure on the minority carrier transport properties of 10 MeV proton irradiated (fluence ∼1014cm−2) Si-dopedβ-Ga2O3Schottky rectifiers. The diffusion length (L) of minority carriers is found to decrease with temperature from 330 nm at 21 °C to 289 nm at 120 °C, with an activation energy of ∼26 meV. This energy corresponds to the presence of shallow Si trap-levels. Extended duration electron beam exposure enhancesLfrom 330 nm to 726 nm at room temperature. The rate of increase forLis lower with increased temperature, with an activation energy of 43 meV. Finally, a brief comparison of the effect of electron injection on proton irradiated, alpha-particle irradiated and a reference Si-dopedβ-Ga2O3Schottky rectifiers is presented.
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Comparison of 10 MeV Neutron Irradiation Effects on NiO/Ga 2 O 3 Heterojunction Rectifiers and Ni/Au/Ga 2 O 3 Schottky Rectifiers
Neutrons generated through charge-exchange9Be (p; ni)9Be reactions, with energies ranging from 0–33 MeV and an average energy of ∼9.8 MeV were used to irradiate conventional Schottky Ga2O3rectifiers and NiO/Ga2O3p-n heterojunction rectifiers to fluences of 1.1–2.2 × 1014cm−2. The breakdown voltage was improved after irradiation for the Schottky rectifiers but was highly degraded for their NiO/Ga2O3counterparts. This may be a result of extended defect zones within the NiO. After irradiation, the switching characteristics were degraded and irradiated samples of both types could not survive switching above 0.7 A or 400 V, whereas reference samples were robust to 1 A and 1 kV. The carrier removal rate in both types of devices was ∼45 cm−1. The forward currents and on-state resistances were only slightly degraded by neutron irradiation.
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- Award ID(s):
- 1856662
- PAR ID:
- 10432297
- Publisher / Repository:
- The Electrochemical Society
- Date Published:
- Journal Name:
- ECS Journal of Solid State Science and Technology
- Volume:
- 12
- Issue:
- 7
- ISSN:
- 2162-8769
- Page Range / eLocation ID:
- Article No. 075004
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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