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In this paper, ZnO thin films with different thicknesses grown on Si (1 0 0) substrates by atomic layer deposition (ALD) method were annealed in nitrogen at the temperatures ranging from 200 to 900 °C. The influences of film thickness and annealing temperature on the structural and optical properties of the ZnO films were systematically investigated by XRD, SEM and RT-PL. All the ALD-ZnO thin films show polycrystalline hexagonal wurtzite structure and a high preferential c -axis orientation. The results show that the crystallinity quality and luminescence performance are both improved by increasing the film thickness. In addition, the loss of oxygen which results in the formation of oxygen vacancies (V O ) is the main reason for the green emission dominating visible band of annealed ZnO thin films. The visible band is dominated by different kinds of defects including oxygen vacancies (V O and V O + ), and interstitial oxygen (I O ) with increasing annealing temperature. High-quality ZnO thin films with good luminescence performance can be obtained for the films annealed at 800 °C in nitrogen. [ABSTRACT FROM AUTHOR]

Highlights: [•] The film thickness affects the microstructure, morphology and optical properties. [•] The crystallinity quality can be improved by increasing the film thickness. [•] The UV absorption edge shifts to longer wavelength. [•] The optical band gap has a small change with increasing the film thickness. [ABSTRACT FROM AUTHOR]

Highlights: [•] AZO thin films were prepared on a-Si films by RF magnetron sputtering. [•] AZO thin films were prepared on a-Si films with various sputtering powers. [•] The crystallinity of AZO films was markedly improved at sputtering power of 1000W. [•] Thickness of a-Si film substrate is being reduced with increasing sputtering power. [•] AZO films deposited on a-Si films are suitable for application in HJ solar cells. [Copyright &y& Elsevier]

Highlights: [•] N-doped Ga2O3 films were deposited on sapphire substrates by radio frequency magnetron sputtering. [•] The samples were annealed in N2, O2, air, respectively. [•] The influence of annealing atmosphere on the structure, morphology and transmittance was investigated. [•] Annealing in nitrogen showed smooth surface and higher transmission in visible range. [•] The red shift of the optical band gap was observed after annealing. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, c-axis oriented AlN films were prepared on sapphire substrate by RF reactive magnetron sputtering at various deposition temperatures (30–700°C). The influences of deposition temperature on the chemical composition, crystalline structure and surface morphology of the AlN films were systematically investigated. The as-deposited films were characterized by X-ray photoelectron spectroscopy (XPS), two-dimensional X-ray diffraction (2D-XRD) and atomic force microscopy (AFM). The experimental results show that it can be successfully grown for high-purity and near-stoichiometric (Al/N=1.12:1) AlN films except for the segregation of a few oxygen impurities exist in the form of Al–O bonding. The chemical composition of as-deposited films is almost independent of substrate temperature in the range of 30–700°C. However, the crystalline structure and surface morphology of the deposited AlN films are strongly influenced by the deposition temperature. The optimum deposition temperature is 300°C, giving a good compromise between crystalline structure and surface morphology to grow AlN films. [Copyright &y& Elsevier]