Microstructure of Mn-doped {gamma}-Ga{sub 2}O{sub 3} epitaxial film on sapphire (0001) with room temperature ferromagnetism

Journal Article · Thu Mar 15 00:00:00 EDT 2007 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.2713349· OSTI ID:20982757

Huang, Rong; Hayashi, Hiroyuki; Oba, Fumiyasu; Tanaka, Isao ^[1]

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1. Department of Materials Science and Engineering, Kyoto University, Yoshida, Sakyo, Kyoto 606-8501 (Japan)

Mn-doped Ga{sub 2}O{sub 3} thin film showing room temperature ferromagnetism has been grown on a sapphire (0001) plane by using a pulsed-laser deposition technique. The microstructure of the Mn-doped film is investigated in detail using selected-area electron diffraction, high-resolution transmission electron microscopy (HRTEM), x-ray energy-dispersive spectroscopy, and electron energy-loss spectroscopy, in comparison with an undoped film. Careful diffraction analysis with the [2110]{sub Al{sub 2}}{sub O{sub 3}} and [1010]{sub Al{sub 2}}{sub O{sub 3}} zone axes of the substrates reveals that the Mn-doped film shows the {gamma}-Ga{sub 2}O{sub 3} phase with a defective spinel structure, while the undoped film shows the {beta}-Ga{sub 2}O{sub 3} phase. The orientation relationship between the film and substrate is determined by electron diffraction and HRTEM from the interface region to be (201){sub {beta}-Ga{sub 2}}{sub O{sub 3}}//(0001){sub Al{sub 2}}{sub O{sub 3}} and [102]{sub {beta}-Ga{sub 2}}{sub O{sub 3}}//[2110]{sub Al{sub 2}}{sub O{sub 3}} or 102{sub {beta}-Ga{sub 2}}{sub O{sub 3}}//2110{sub Al{sub 2}}{sub O{sub 3}} for the undoped film, and (111){sub {gamma}-Ga{sub 2}}{sub O{sub 3}}//(0001){sub Al{sub 2}}{sub O{sub 3}} and [211]{sub {gamma}-Ga{sub 2}}{sub O{sub 3}}//[2110]{sub Al{sub 2}}{sub O{sub 3}} or [211]{sub {gamma}-Ga{sub 2}}{sub O{sub 3}}//[2110]{sub Al{sub 2}}{sub O{sub 3}} for the Mn-doped film. Mn ions are uniformly dissolved in the film with 7.8 cation % and no detectable precipitates are found. Mn-L{sub 2,3} energy-loss near-edge structure reveals that Mn ions take the valency of 2+, which is consistent with Mn-L{sub 2,3} near edge x-ray absorption results in our previous report.

• OSTI ID: 20982757
• Journal Information: Journal of Applied Physics, Vol. 101, Issue 6; Other Information: DOI: 10.1063/1.2713349; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ABSORPTION
CRYSTAL STRUCTURE
DOPED MATERIALS
ELECTRON DIFFRACTION
ENERGY BEAM DEPOSITION
ENERGY LOSSES
ENERGY-LOSS SPECTROSCOPY
EPITAXY
FERROMAGNETISM
GALLIUM OXIDES
LASER RADIATION
MANGANESE IONS
MICROSTRUCTURE
PRECIPITATION
PULSED IRRADIATION
SAPPHIRE
SPINELS
TEMPERATURE RANGE 0273-0400 K
THIN FILMS
TRANSMISSION ELECTRON MICROSCOPY