α-Ga2O3 has the corundum structure analogous to that of α-Al2O3. The bandgap energy of α-Ga2O3 is 5.3 eV and is greater than that of β-Ga2O3, making the α-phase attractive for devices that benefit from its wider bandgap. The O-H and O-D centers produced by the implantation of H+ and D+ into α-Ga2O3 have been studied by infrared spectroscopy and complementary theory. An O-H line at 3269 cm-1 is assigned to H complexed with a Ga vacancy (VGa), similar to the case of H trapped by an Al vacancy (VAl) in α-Al2O3. The isolated VGa and VAl defects in α-Ga2O3 and α-Al2O3 are found by theory to have a “shifted” vacancy-interstitial-vacancy equlibrium configuration, similar to VGa in β-Ga2O3 which also has shifted structures. However, the addition of H causes the complex with H trapped at an unshifted vacancy to have the lowest energy in both α-Ga2O3 and α-Al2O3.
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H trapping at the metastable cation vacancy in α -Ga 2 O 3 and α -Al 2 O 3
α-Ga2O3has the corundum structure analogous to that of α-Al2O3. The bandgap energy of α-Ga2O3is 5.3 eV and is greater than that of β-Ga2O3, making the α-phase attractive for devices that benefit from its wider bandgap. The O–H and O–D centers produced by the implantation of H+and D+into α-Ga2O3have been studied by infrared spectroscopy and complementary theory. An O–H line at 3269 cm−1is assigned to H complexed with a Ga vacancy (VGa), similar to the case of H trapped by an Al vacancy (VAl) in α-Al2O3. The isolated VGaand VAldefects in α-Ga2O3and α-Al2O3are found by theory to have a “shifted” vacancy-interstitial-vacancy equilibrium configuration, similar to VGain β-Ga2O3, which also has shifted structures. However, the addition of H causes the complex with H trapped at an unshifted vacancy to have the lowest energy in both α-Ga2O3and α-Al2O3.
more » « less- Award ID(s):
- 1856662
- NSF-PAR ID:
- 10366905
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Applied Physics Letters
- Volume:
- 120
- Issue:
- 19
- ISSN:
- 0003-6951
- Page Range / eLocation ID:
- Article No. 192101
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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