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Title: Point defect creation by proton and carbon irradiation of α-Ga 2 O 3
Films of α-Ga 2 O 3 grown by Halide Vapor Phase Epitaxy (HVPE) were irradiated with protons at energies of 330, 400, and 460 keV with fluences 6 × 10 15  cm −2 and with 7 MeV C 4+ ions with a fluence of 1.3 × 10 13  cm −2 and characterized by a suite of measurements, including Photoinduced Transient Current Spectroscopy (PICTS), Thermally Stimulated Current (TSC), Microcathodoluminescence (MCL), Capacitance–frequency (C–f), photocapacitance and Admittance Spectroscopy (AS), as well as by Positron Annihilation Spectroscopy (PAS). Proton irradiation creates a conducting layer near the peak of the ion distribution and vacancy defects distribution and introduces deep traps at E c -0.25, 0.8, and 1.4 eV associated with Ga interstitials, gallium–oxygen divacancies V Ga –V O , and oxygen vacancies V O . Similar defects were observed in C implanted samples. The PAS results can also be interpreted by assuming that the observed changes are due to the introduction of V Ga and V Ga –V O .  more » « less
Award ID(s):
1856662
PAR ID:
10340721
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Journal of Applied Physics
Volume:
132
Issue:
3
ISSN:
0021-8979
Page Range / eLocation ID:
035701
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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