Investigations of ZnO thin films grown on c-Al2O3 by pulsed laser deposition in N2 + O2 ambient
Idioma
en
Article de revue
Este ítem está publicado en
physica status solidi (c). 2008, vol. 5, n° 9, p. 3084-3087
Wiley
Resumen en inglés
ZnO films were deposited on c-Al2O3 using pulsed laser deposition both with and without N2 in the growth ambient. X-ray diffraction revealed poorer crystal quality and surface morphology for one-step growths with N2 in the ...Leer más >
ZnO films were deposited on c-Al2O3 using pulsed laser deposition both with and without N2 in the growth ambient. X-ray diffraction revealed poorer crystal quality and surface morphology for one-step growths with N2 in the ambient. A marked improvement in both the crystallographic and surface quality was obtained through use of two-step growths employing nominally undoped ZnO buffer layers prior to growth with N2 in the ambient. All films showed majority n-type conduction in Hall measurements. Post-annealing for 30 minutes at 600 ºC in O2 systematically reduced both the carrier concentration and the conductivity. A base room temperature carrier concentration of 1016 cm-3 was linked to Al diffusing from the substrate. 4.2 K photoluminescence spectra exhibited blue bands associated with the growths having N2 in the ambient. Temperature dependent Hall measurements were consistent with N being incorporated in the films. Processed devices did not, however, show rectifying behaviour or electroluminescence.< Leer menos
Palabras clave en inglés
X-ray diffraction
Thin film structure
Morphology
II–VI semiconductors
Laser deposition
Orígen
Importado de HalCentros de investigación