Microstructure and interface control of GaN/MgAl{sub 2}O{sub 4} grown by metalorganic chemical vapor deposition: Substrate-orientation dependence

Journal Article · Fri Jul 15 04:00:00 EDT 2011 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.3606430· OSTI ID:22036662

He, G; Chikyow, T ^[1]; Chichibu, Shigefusa F ^[2]

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1. Advanced Electric Materials Center, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)
2. CANTech, Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577 (Japan)

GaN films with single-crystal and polycrystalline structure were deposited on (111) and (100) MgAl{sub 2}O{sub 4} substrates by metalorganic chemical vapor deposition using a substrate modified by chemical etching and thermal passivation. The interface structure and chemical bonding state of the GaN/MgAl{sub 2}O{sub 4} interface was investigated using angle-resolved x-ray photoelectron spectroscopy and resulting valence band spectra. Our results indicate that the Al{sub 2}O{sub 3} buffered layer induced by thermal passivation of the (111) substrate remains unchanged during GaN deposition, which is primarily responsible for the epitaxial growth of GaN on (111) MgAl{sub 2}O{sub 4} substrate. However, for the as-processed (100) substrate, interfacial reactions take place between the formed MgO-terminated surface and GaN films and GaN with a polycrystalline structure on (100) substrate forms. From the interface engineering viewpoint, the appropriate interface modification will allow control of the interface reaction to obtain high-quality GaN films for future optoelectronic devices.

• OSTI ID: 22036662
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 2 Vol. 110; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALUMINIUM OXIDES
CHEMICAL BONDS
CHEMICAL VAPOR DEPOSITION
CRYSTAL GROWTH
CRYSTAL STRUCTURE
EPITAXY
ETCHING
FILMS
GALLIUM NITRIDES
INTERFACES
LAYERS
MAGNESIUM OXIDES
MICROSTRUCTURE
MONOCRYSTALS
POLYCRYSTALS
SEMICONDUCTOR MATERIALS
SUBSTRATES
VALENCE
X-RAY PHOTOELECTRON SPECTROSCOPY