A Zinc(II) complex of hexamethylenetetramine was prepared as a single source precursor and used to deposit zinc oxynitride thin films. The thin films were deposited on soda-lime glass substrates using the Metal Organi...A Zinc(II) complex of hexamethylenetetramine was prepared as a single source precursor and used to deposit zinc oxynitride thin films. The thin films were deposited on soda-lime glass substrates using the Metal Organic Chemical Vapour Deposition (MOCVD) technique at the deposition temperature of 370°C and 390°C, respectively. The Fourier Transform Infrared Spectroscopy (FTIR) was used to determine the functional groups in the precursor, with stretching frequency for O-H, N-H, and C-H observed. The deposited films were characterized using UV-Visible Spectroscopy, Scanning Electron Microscopy (SEM), Elemental diffraction X-ray (EDX), and X-ray Diffractometer (XRD). A direct bandgap of 3.15 eV and 3.18 eV was obtained from the film deposited at 370°C and 390°C, respectively, using the Envelope Method. In comparison, a bandgap of 3.19 eV and 3.21 eV was obtained using the absorption spectrum fitting (ASF) method. The SEM revealed that the film is homogeneous, dense, and compact, composed of cluster grains. The EDX confirmed the presence of Zinc, Nitrogen and Oxygen. The X-ray Diffraction indicated the polycrystalline nature of the film.展开更多
Chromium (Cr) doped Zinc oxide ZnO thin films were deposited onto glass substrates by Metal Organic Chemical Vapour Deposition (MOCVD) technique with varying dopant concentration at a temperature of 420°C. The ef...Chromium (Cr) doped Zinc oxide ZnO thin films were deposited onto glass substrates by Metal Organic Chemical Vapour Deposition (MOCVD) technique with varying dopant concentration at a temperature of 420°C. The effect of the chromium concentration on morphological, structural, optical, electrical and gas sensing properties of the films were investigated. The scanning electron microscopy results revealed that the Cr concentration has great influence on the crystallinity, surface smoothness and grain size. X-ray diffraction (XRD) studies shows that films were polycrystalline in nature and grown as a hexagonal wurtzite structure. A direct optical band energy gap of 3.32 to 3.10 eV was obtained from the optical measurements. The transmission was found to decrease with increasing Cr doping concentration. Rutherford Backscattering Spectroscopy (RBS) analysis also demonstrates that Cr ions are substitutionally incorporated into ZnO. I-V characteristic of the film shows a resistivity ranges from 1.134 × 10-2 · cm to 1.24 × 10-2 · cm at room temperature. The gas sensing response of the films were enhanced with incorporation of Cr as a dopant with optimum operating temperature around 200°C.展开更多
文摘A Zinc(II) complex of hexamethylenetetramine was prepared as a single source precursor and used to deposit zinc oxynitride thin films. The thin films were deposited on soda-lime glass substrates using the Metal Organic Chemical Vapour Deposition (MOCVD) technique at the deposition temperature of 370°C and 390°C, respectively. The Fourier Transform Infrared Spectroscopy (FTIR) was used to determine the functional groups in the precursor, with stretching frequency for O-H, N-H, and C-H observed. The deposited films were characterized using UV-Visible Spectroscopy, Scanning Electron Microscopy (SEM), Elemental diffraction X-ray (EDX), and X-ray Diffractometer (XRD). A direct bandgap of 3.15 eV and 3.18 eV was obtained from the film deposited at 370°C and 390°C, respectively, using the Envelope Method. In comparison, a bandgap of 3.19 eV and 3.21 eV was obtained using the absorption spectrum fitting (ASF) method. The SEM revealed that the film is homogeneous, dense, and compact, composed of cluster grains. The EDX confirmed the presence of Zinc, Nitrogen and Oxygen. The X-ray Diffraction indicated the polycrystalline nature of the film.
文摘Chromium (Cr) doped Zinc oxide ZnO thin films were deposited onto glass substrates by Metal Organic Chemical Vapour Deposition (MOCVD) technique with varying dopant concentration at a temperature of 420°C. The effect of the chromium concentration on morphological, structural, optical, electrical and gas sensing properties of the films were investigated. The scanning electron microscopy results revealed that the Cr concentration has great influence on the crystallinity, surface smoothness and grain size. X-ray diffraction (XRD) studies shows that films were polycrystalline in nature and grown as a hexagonal wurtzite structure. A direct optical band energy gap of 3.32 to 3.10 eV was obtained from the optical measurements. The transmission was found to decrease with increasing Cr doping concentration. Rutherford Backscattering Spectroscopy (RBS) analysis also demonstrates that Cr ions are substitutionally incorporated into ZnO. I-V characteristic of the film shows a resistivity ranges from 1.134 × 10-2 · cm to 1.24 × 10-2 · cm at room temperature. The gas sensing response of the films were enhanced with incorporation of Cr as a dopant with optimum operating temperature around 200°C.