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Title: Growth and characterization of α-Ga 2 O 3 on sapphire and nanocrystalline β-Ga 2 O 3 on diamond substrates by halide vapor phase epitaxy
Halide vapor phase epitaxial (HVPE) Ga 2 O 3 films were grown on c-plane sapphire and diamond substrates at temperatures up to 550 °C without the use of a barrier dielectric layer to protect the diamond surface. Corundum phase α-Ga 2 O 3 was grown on the sapphire substrates, whereas the growth on diamond resulted in regions of nanocrystalline β-Ga 2 O 3 (nc-β-Ga 2 O 3 ) when oxygen was present in the HVPE reactor only during film growth. X-ray diffraction confirmed the growth of α-Ga 2 O 3 on sapphire but failed to detect any β-Ga 2 O 3 reflections from the films grown on diamond. These films were further characterized via Raman spectroscopy, which revealed the β-Ga 2 O 3 phase of these films. Transmission electron microscopy demonstrated the nanocrystalline character of these films. From cathodoluminescence spectra, three emission bands, UVL′, UVL, and BL, were observed for both the α-Ga 2 O 3 /sapphire and nc-Ga 2 O 3 /diamond, and these bands were centered at approximately 3.7, 3.2, and 2.7 eV.
Authors:
; ; ; ; ; ; ; ;
Award ID(s):
1856662
Publication Date:
NSF-PAR ID:
10378555
Journal Name:
Journal of Vacuum Science & Technology A
Volume:
40
Issue:
6
Page Range or eLocation-ID:
062703
ISSN:
0734-2101
Sponsoring Org:
National Science Foundation
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