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Localized UV emitters on the surface of β-Ga₂O₃.

ABSTRACT: Monoclinic gallium oxide (β-Ga₂O₃) is attracting intense focus as a material for power electronics, thanks to its ultra-wide bandgap (4.5-4.8 eV) and ability to be easily doped n-type. Because the holes self-trap, the band-edge luminescence is weak; hence, β-Ga₂O₃ has not been regarded as a promising material for light emission. In this work, optical and structural imaging methods revealed the presence of localized surface defects that emit in the near-UV (3.27 eV, 380 nm) when excited by sub-bandgap light. The PL emission of these centers is extremely bright-50 times brighter than that of single-crystal ZnO, a direct-gap semiconductor that has been touted as an active material for UV devices.

SUBMITTER: Huso J

PROVIDER: S-EPMC7712825 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Localized UV emitters on the surface of β-Ga2O3.

Huso Jesse J McCluskey Matthew D MD Yu Yinchuan Y Islam Md Minhazul MM Selim Farida F

Scientific reports 20201203 1

Monoclinic gallium oxide (β-Ga2O3) is attracting intense focus as a material for power electronics, thanks to its ultra-wide bandgap (4.5-4.8 eV) and ability to be easily doped n-type. Because the holes self-trap, the band-edge luminescence is weak; hence, β-Ga2O3 has not been regarded as a promising material for light emission. In this work, optical and structural imaging methods revealed the presence of localized surface defects that emit in the near ...[more]

PMID: 33273495

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