Transparent thin films of CdO:Ce has been deposited on to glass and silicon substrates by spray pyrolysis technique for various concentrations of cerium (2, 4, and 6 Vol.%). CdO:Ce films were characterized using different techniques such as X-ray diffraction (XRD), atomic force microscopy(AFM) and optical properties. XRD analysis show that CdO films exhibit cubic crystal structure with (1 1 1) preferred orientation and the intensity of the peak increases with increasing's of Ce contain when deposited films on glass substrate, while for silicon substrate, the intensity of peaks decreases, the results reveal that the grain size of the prepared thin film is approximately (73.75-109.88) nm various with increased of cerium content. With a surface roughness of (0.871–16.2) nm as well as root mean square of (1.06-19.7) nm for glass substrate, while for silicon (84.79-107.48) nm, for a pure CdO and doped with Ce (2, 4, and 6 Vol.%). The 300-nm-thin CdO films showed that the optical energy band gap equal 2.6 eV, and increases with increasing doping until reaches a maximum value of 3.25 eV when doping levels 6 Vol.%.
PbxCd1-xSe compound with different Pb percentage (i.e. X=0,
0.025, 0.050, 0.075, and 0.1) were prepared successfully. Thin films
were deposited by thermal evaporation on glass substrates at film
thickness (126) nm. The optical measurements indicated that
PbxCd1-xSe films have direct optical energy gap. The value of the
energy gap decreases with the increase of Pb content from 1.78 eV to
1.49 eV.
ZnO thin films have been prepared by pulse laser deposition technique at room temperatures (RT). These films were deposited on GaAs substrate to form the ZnO/GaAs heterojunction solar cell. The effect of annealing temperatures at ( RT,100, 200)K on structural and optical properties of ZnO thin films has been investigated. The X-ray diffraction analysis indicated that all films have hexagonal polycrystalline structure. AFM shows that the grains uniformly distributed with homogeneous structure. The optical absorption spectra showed that all films have direct energy gap. The band gap energy of these films decreased with increasing annealing temperatures. From the electrical properties, the carriers have n-type conductivity. From
... Show MoreThis paper reports on the laser emission properties of the BBQ dye in poly (methyl meth-acrylate)(PMMA). This host material combines the advantages of an organic environment for dye with the thermoptical mechanical properties of an organic dye. A BBQ dye solid solution in PMMA polymer. A nitrogen laser in untuned laser cavity has pumped thin films. We developed the concentration and the thickness to get high efficiency. The laser efficiency had been increased from 7% at thickness 1.5 m to 16.5% at thickness 3.5m, and from 1% to 10% when concentration increased from 1x10-5M to 1x10-3 M
Nanostructural cupric oxide (CuO) films were prepared on Si and glass substrate by pulsed laser deposition technique (PLD) using laser Nd:YAG, using different laser pulses energies from 200 to 600 mJ. The X-ray diffraction pattern (XRD) of the films showed a polycrystalline structure with a monoclinic symmetry and preferred orientation toward (111) plane with nano structure. The crystallite size was increasing with increasing of laser pulse energy. Optical properties was characterized by using UV–vis spectrometer in the wave lengthrange (200-1100) nm at room temperature. The results showed that the transmission spectrum decreases with the laser pulses energy increase. Sensitivity of NO2 gas at different operating temperatures, (50°C,
... Show MoreBulk AlxSb1-x samples were prepared with different x ratios (0.1, 0.3, 0.5, 0.7 and 0.9) by quenching technique. This was done throughout mixing the aluminum and antimony elements according to the proper atomic weight and put them in an evacuated quartz ampoule which then sealed and heated at 1273 K for five hours and left to cool in air. Thin films of AlxSb1-xwere prepared by using thermal evaporation under vacuum of 10-5 mbar on glass substrates at room temperature with deposition rate (10-15nm/min) at thickness of ∼ 500nm. The structures of AlxSb1-x bulk and thin films have been studied by X–ray diffraction technique. The results showed that all alloys have polycrystalline structures and the p
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Copper oxide thin films were synthesized by using spray pyrolysis deposition technique, in the temperature around 400°C in atmosphere from alcoholic solutions. Copper (II) chloride as precursor and glass as a substrate. The textural and structural properties of the films were characterized by atomic force microscopy (AFM), X-ray diffraction (XRD). The average particle size determined from the AFM images ranged from 30 to 90 nm and the roughness average was equal to 9.3 nm. The XRD patterns revealed the formation of a polycrystalline hexagonal CuO. The absorption and transmission spectrum, band gap, film thickness was investigated. The films were tested as an |
In the present work the preparation of Cu2S alloy was done throughout mixing the sulphur and copper elements according to the proper atomic weight and then put in an evacuated quartz ampoule which then sealed and heated at 1273 K for five hours and left to cool. Thin films from Cu2S powder thicknesses of ~300nm were prepared by thermal evaporation technique on a glass substrate and under vacuum of 10 -5 mbar with rate of deposition 25nm/sec. The prepared thin films subjected to heat treatment at different temperatures(300, 373 , 473 and 573 K)for half an hour. The structures of Cu2S powder and films have been studied by X–ray diffraction technique. The result reveals that the preparedalloy has cubic structure a
... Show MoreIn this study, Cobalt Oxide nanostructure was successfully prepared using the chemical spray pyrolysis technique. The cobalt oxide phase was analysed by X-ray Diffraction (XRD) and proved the preparation of two cobalt oxide phases which are Co3O4 and CoO phases. The surface morphology was characterized by Scanning Electron Microscope (SEM) images showing the topography of the sample with grain size smaller than 100 nm. The optical behavior of the prepared material was studied by UV-Vis spectrophotometer. The band gap varied as 1.9 eV and 2.6 eV for Co3O4 prepared from cobalt sulphate precursor, 2.03 eV and 4.04 eV for Co3O4 prepared from cobalt nitrate precursor, 2.04 eV and 4.01 eV for CoO prepared from cobalt chloride precursor where th
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