During of Experimental result of this work , we found that the change of electrical conductivity proprieties of tin dioxide with the change of gas concentration at temperatures 260oC and 360oC after treatment by photons rays have similar character after treatment isothermally. We found that intensive short duration impulse annealing during the fractions of a second leads to crystallization of the films and to the high values of its gas sensitivity.
In this study, doped thin cadmium peroxide films were prepared by pulsed laser deposition with different doping concentrations of aluminium of 0.0, 0.1, 0.3, and 0.5 wt.% for CdO2(1-X)Al(X) and thicknesses in the range of 200 nm. XRD patterns suggest the presence of cubic CdO2 and the texture factor confirms that the (111) plane was the preferential growth plane, where the texture factor and the grain size decreased from 2.02 to 9.75 nm, respectively, in the pure sample to 1.88 and 5.65 nm, respectively, at a concentration of 0.5 wt%. For the predominant growth plane, the deviation of the diffraction angle Δθ and interplanar distance Δd from the standard magnitudes was 2.774° and 0.318 Å, respectively, for the pure sample decreased to
... Show MoreThe optical energy gap(Eopt) and the width of the tails of localized states in the band gap (?E) for Se:2%Sb thin films prepared by thermal co-evaporation method as a function of annealing temperature are studied in the photon energy range ( 1 to 5.4)eV.Se2%Sb film was found to be indirect transition with energy gap of (1.973,2.077, 2.096, 2.17) eV at annealing temperature (295,370,445,520)K respectively. The Eopt and ?E of Se:2%Sb films as a function of annealing temperature showed an increase in Eopt and a decrease in ?E with increasing the annealing temperature. This behavior may be related to structural defects and dangling bonds.
Thin films Tin sulfide SnS pure and doped with different ratios of Cu (X=0, 0.01, 0.03 and 0.05) were prepared using thermal evaporation with a vacuum of 4*10-6mbar on two types of substrates n-type Si and glass with (500) nm thickness for solar cell application. X-ray diffraction and AFM analysis were carried out to explain the influence of Cu ratio dopant on structural and morphological properties respectively. SnS phase appeared forming orthorhombic structure with preferred orientation (111), increase the crystallinity degree and surface roughness with increase Cu ratio. UV/Visible measurement revealed the decrease in energy gap from 1.9eV for pure SnS to 1.5 for SnS: Cu (0.05) making these samples suitable f
... Show MoreCdO:NiO/Si solar cell film was fabricated via deposition of CdO:NiO in different concentrations 1%, 3%, and 5% for NiO thin films in R.T and 723K, on n-type silicon substrate with approximately 200 nm thickness using pulse laser deposition. CdO:NiO/n-Si solar cell photovoltaic properties were examined under 60 mW/cm2 intensity illumination. The highest efficiency of the solar cell is 2.4% when the NiO concentration is 0.05 at 723K.
Zinc oxide thin films were deposited by chemical spray pyrolysis onto glass substrates which are held at a temperature of 673 K. Some structural, electrical, optical and gas sensing properties of films were studied. The resistance of ZnO thin film exhibits a change of magnitude as the ambient gas is cycled from air to oxygen and nitrogen dioxide
A polycrystalline CdTe film has been prepared by thermal evaporation technique on glass substrate at substrate temperature 423 K with 1.0 m thicknesses. The film was heated at various annealing temperature under vacuum (Ta =473, 523 and K). Some of physical properties of prepared films such as structural and optical properties were investigated. The patterns of X-ray diffraction analysis showed that the structure of CdTe powder and all films were polycrystalline and consist of a mixture of cubic and hexagonal phases and preferred orientation at (111) direction.
The optical measurements showed that un annealed and annealed CdTe films had direct energy gap (Eg). The Eg increased with increasing Ta. The refractive index and the real p
We report the detail characterizations and
In this research tri metal oxides were fabricated by simple chemical spray pyrolysis technique from (Sn(NO3)2.20 H2O, Zn(NO3)2.6 H2O, Cd(NO3)2.4 H2O) salts at concentration 0.1M with mixing weight ratio 50:50 were fabricated on silicon substrate n-type (111). (with & without the presence of grooves by the following diemensions (20μm width, 7.5μm depth) with thickness was about ( 0.1 ±0.05 µm) using water soluble as precursors at a substrate temperature 550 ºC±5, with spray distance (15 cm) and their gas sensing properties toward H2S gas at different concentrations (10,50,100,500 ppmv) in air were investigated at room te
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