Correlation between Zn vacancies and photoluminescence emission in ZnO films
نویسندگان
چکیده
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. © 2006 American Institute of Physics. DOI: 10.1063/1.2175476
منابع مشابه
Correlation between crystal structure and optical properties of copper- doped ZnO thin films
ZnO and Cu doped[1] (CZO) thin films were prepared by radio frequency sputtering. The structural and optical properties of thin films were investigated using X-ray diffraction (XRD), atomic force microscopy (AFM), optical spectrophotometer, and photoluminescence (PL) techniques. ZnO thin films showed crystalline and micro-stress defects in the crystal lattice. Annealing of CZO thin films increa...
متن کاملEffects of doping and annealing on properties of ZnO films grown by atomic layer deposition
Undoped and Al-doped ZnO films were synthesized by atomic layer deposition at 150°C and then annealed at 350°C in different atmospheres. Effects of doping and annealing on the film growth mode and properties were investigated. The undoped film has strong UV emission and weak Zn interstitial emission. Annealing introduces O vacancies, decreases Zn interstitials, and results in weakening and blue...
متن کاملFormation of isolated Zn vacancies in ZnO single crystals by absorption of ultraviolet radiation: a combined study using positron annihilation, photoluminescence, and mass spectroscopy.
Positron annihilation spectra reveal isolated zinc vacancy (V(Zn)) creation in single-crystal ZnO exposed to 193-nm radiation at 100 mJ/cm(2) fluence. The appearance of a photoluminescence excitation peak at 3.18 eV in irradiated ZnO is attributed to an electronic transition from the V(Zn) acceptor level at ~100 meV to the conduction band. The observed V(Zn) density profile and hyperthermal Zn(...
متن کاملSynthesis and characterization of ZnO nanowires by thermal oxidation of Zn thin films at various temperatures.
In this research high-quality zinc oxide (ZnO) nanowires have been synthesized by thermal oxidation of metallic Zn thin films. Metallic Zn films with thicknesses of 250 nm have been deposited on a glass substrate by the PVD technique. The deposited zinc thin films were oxidized in air at various temperatures ranging between 450 °C to 650 °C. Surface morphology, structural and optical properties...
متن کاملThe Modulation of Optical Property and its Correlation with Microstructures of ZnO Nanowires
ZnO nanowires with both good crystallinity and oxygen vacancies defects were synthesized by thermal oxidation of Zn substrate pretreated in concentrated sulfuric acid under the air atmosphere, Ar- and air-mixed gas stream. The photoluminescence spectra reveal that only near-band-edge (NBE) emission peak was observed for the sample grown in the air atmosphere; the broad blue-green and the red-sh...
متن کامل