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Title: Variable temperature probing of minority carrier transport and optical properties in p -Ga 2 O 3
Electron beam-induced current in the temperature range from 304 to 404 K was employed to measure the minority carrier diffusion length in metal–organic chemical vapor deposition-grown p-Ga 2 O 3 thin films with two different concentrations of majority carriers. The diffusion length of electrons exhibited a decrease with increasing temperature. In addition, the cathodoluminescence emission spectrum identified optical signatures of the acceptor levels associated with the V Ga − –V O ++ complex. The activation energies for the diffusion length decrease and quenching of cathodoluminescence emission with increasing temperature were ascribed to the thermal de-trapping of electrons from V Ga − –V O ++ defect complexes.
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Award ID(s):
1856662 1802208
Publication Date:
Journal Name:
APL Materials
Sponsoring Org:
National Science Foundation
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