Synchrotron x-ray absorption near edge structures (XANES) measurements of In L3 edge is used in conjunction with first principles calculations to characterize rf magnetron sputtered indium oxynitride at different O contents. Good agreement between the measured and the independently calculated spectra are obtained. Calculations show that the XANES spectra of this alloy are sensitive to the coordination numbers of the In atoms, i.e., fourfold for indium nitride-like structures and sixfold for indium oxide-like structures, but not to the substitution of nearest neighbor N by O or vice versa.

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Local structure of indium oxynitride thin films grown on silicon substrates was investigated by X-ray absorption fine structure technique incorporated with first principle calculations. The thin films were grown by using reactive gas timing radio frequency (RF) magnetron sputtering technique with nitrogen (N 2 ) and oxygen (O 2 ) as reactive gasses. The reactive gasses were interchangeably fed into sputtering system at five different time intervals. The gas feeding time intervals of N 2 :O 2 are 30 : 0, 30 : 5, 30 : 10, 30 : 20 and 10 : 30 s, respectively. The analysis results can be divided into three main categories. Firstly, the films grown with 30 : 0 and 30 : 5 s gas feeding time intervals are wurtzite structure indium nitride with 25 and 43% oxygen contaminations, respectively. Secondary, the film grown with 10 : 30 s gas feeding time intervals is bixbyite structure indium oxide. Finally, the films are alloying between indium nitride and indium oxide for other growth condition. The fitted radial distribution spectra, the structural parameters and the combination ratios of the alloys are discussed.

Indium Oxynitride (InON) thin films prepared by Reactive gas-timing RF magnetron sputtering technique are investigated using X-ray absorption fine structure and first principle calculation. It was found from the former study[2] that optical and electrical properties of these films highly depended on its gas-timing ratio in the sputtering process. Therefore structural investigations of these films are required in order to describe the relation between the gas-timing ratio and their optical properties. The results show that local structure of the InON thin films consist of both indium oxide (In 2 O 3 ) and indium nitride (InN) phase.

Al-doped ZnO nanoparticles were synthesized by sonochemical method from zinc acetate dehydrate and aluminum acetate as starting precursors. The deionized (DI) water was selected as the solvent. Sonication of the precursor was performed by a Sonics Model VCX 750 for 30 minutes until precipitated product was finally obtained. The as-precipitated powders were calcined at different temperature range of 550-1100 °C for 2 hr. For all samples, their crystal structures were investigated by X-ray diffraction (XRD) and surface morphologies were observed by scanning electron microscope (SEM). The XRD results revealed that, the purity of as-synthesized powders increases when the calcination temperature increases. Moreover, it is noticed that the AlZnO partial peaks will appear when the as-synthesized powders were calcined at 800 – 1000 °C. In addition, SEM micrographs show the increase of agglomeration and the particles when the calcination temperature increases.

This work investigates changes in the chemical composition of InON thin films, grown by reactive gas-timing rf magnetron sputtering with different O2:N2 timing ratio characterized by Auger Electron Microscope (AES), Raman Spectroscopy which are well correlated with the electrical properties of films. The existence of nitrogen and oxygen in the deposited InON thin films was revealed by AES. Two Raman active optical phonons have been clearly observed and assigned to InN E1(TO) at ~470 cm-1 and E1(LO) at ~570 cm-1 and also shifted with different O2:N2 timing ratio. The carrier mobility of InON thin films was decreased when the ratio of O2:N2 timing is increased.