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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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Impact of radiation and electron trapping on minority carrier transport in p -Ga 2 O 3
Highly resistive undoped p-type gallium oxide samples were subjected to cumulative proton irradiation with energies ranging from 25 to 70 keV and doses in the 1.6 × 1014–3.6 × 1014cm−2range. Proton irradiation resulted in up to a factor of 2 reduction of minority electron diffusion length in the samples for temperatures between ∼ 300 and 400 K. Electron injection into the samples under test using a scanning electron microscope beam leads to pronounced elongation of diffusion length beyond the pre-irradiation values, thus demonstrating stable (days after injection) recovery of adverse radiation impact on minority carrier transport. The activation energy of 91 meV estimated from the temperature dependent diffusion length vs electron injection duration experiments is likely related to the local potential barrier height for native defects associated with the phenomenon of interest.
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- PAR ID:
- 10367928
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Applied Physics Letters
- Volume:
- 120
- Issue:
- 23
- ISSN:
- 0003-6951
- Page Range / eLocation ID:
- Article No. 233503
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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