Optically active vacancies in GaN grown on Si substrates probed using a monoenergetic positron beam

Journal Article · Mon Feb 24 04:00:00 EST 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4866966· OSTI ID:22293049

Uedono, Akira; Zhang, Yang; Yoshihara, Nakaaki ^[1]; Fujishima, Tatsuya; Palacios, Tomás ^[2]; Cao, Yu; Laboutin, Oleg; Johnson, Wayne ^[3]; Ishibashi, Shoji ^[4]; Sumiya, Masatomo ^[5]

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1. Division of Applied Physics, Faculty of Pure and Applied Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan)
2. Microsystems Technology Laboratories, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307 (United States)
3. IQE, 200 John Hancock Road, Taunton, Massachusetts 01581 (United States)
4. Nanosystem Research Institute “RICS,” National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568 (Japan)
5. Wide Bandgap Material Group, National Institute for Materials Science, Tsukuba 305-0044 (Japan)

Native defects in GaN layers grown on Si substrates by metal organic chemical vapor deposition have been studied using a monoenergetic positron beam. Measurements of Doppler broadening spectra of the annihilation radiation for GaN layers showed that optically active vacancy-type defects were formed in the layers. Charge transition of the defects due to electron capture was found to occur when the layers were irradiated by photons with energy above 2.71 eV. The concentration of such defects increased after 600–800 °C annealing, but the defects have not been annealed out even at 1000 °C. They were identified as Ga-vacancy-type defects, such as complexes between Ga vacancies and carbon impurities, and the relationship between their charge transition and optical properties were discussed.

• OSTI ID: 22293049
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 8 Vol. 104; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANNEALING
ANNIHILATION
CARBON
CHEMICAL VAPOR DEPOSITION
CONCENTRATION RATIO
CRYSTAL DEFECTS
CRYSTAL GROWTH
DOPPLER BROADENING
ELECTRON CAPTURE
GALLIUM NITRIDES
IMPURITIES
LAYERS
OPTICAL PROPERTIES
ORGANOMETALLIC COMPOUNDS
PHOTONS
POSITRON BEAMS
SILICON
VACANCIES