0000000000590350

AUTHOR

Filip Tuomisto

showing 2 related works from this author

Correlation between Zn vacancies and photoluminescence emission in ZnO films.

2006

Photoluminescence and positron annihilation spectroscopy have been used to characterize and identify vacancy-type defects produced in ZnO films grown on sapphire by metal-organic chemical-vapor deposition. The photoluminescence of the samples in the near band edge region has been studied, paying particular attention to the emission at 370.5 nm (3.346 eV). This emission has been correlated to the concentration of Zn vacancies in the films, which has been determined by positron annihilation spectroscopy. Jesus.Zuniga@uv.es Vicente.Munoz@uv.es

PhotoluminescenceMaterials scienceAstrophysics::High Energy Astrophysical PhenomenaEdge regionAnalytical chemistrySemiconductor thin filmsGeneral Physics and AstronomyPositron annihilation spectroscopyCondensed Matter::Materials Science:FÍSICA [UNESCO]Zinc compoundsMetalorganic vapour phase epitaxyDeposition (law)Positron annihilationCondensed matter physicsCondensed Matter::OtherPhysicsWide-bandgap semiconductorpositron annihilationUNESCO::FÍSICACacancies (crystal)II-VI semiconductorsWide band gap semiconductorsZn vacanciesMOCVDSapphireZnOphotoluminescenceZinc compounds ; II-VI semiconductors ; Wide band gap semiconductors ; Semiconductor thin films ; Positron annihilation ; Cacancies (crystal) ; MOCVD
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Characterization of non-polar ZnO layers with positron annihilation spectroscopy

2008

We applied positron annihilation spectroscopy to study the effect of growth polarity on the vacancy defects in ZnO grown by metal-organic vapor phase deposition on sapphire. Both c-plane and a-plane ZnO layers were measured, and Zn vacancies were identified as the dominant defects detected by positrons. The results are qualitatively similar to those of earlier experiments in GaN. The Zn vacancy concentration decreases in c-plane ZnO by almost one order of magnitude (from high 10 cm−3 to low 10 cm−3) when the layer thickness is increased from 0.5 to 2 μm. Interestingly, in a-plane ZnO the Zn vacancy concentration is constant at a level of about 2×10 cm−3 in all the samples with thicknesses v…

PositronMaterials scienceVacancy defectAnnihilation radiationSapphireAnalytical chemistryGeneral Physics and AstronomyAnisotropyDeposition (law)Positron annihilation spectroscopyDoppler broadening
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