A polycrystalline CdSe thin films doped with (5wt%) of Cu was fabricated using vacuum evaporation technique in the substrate temperature range(Ts=RT-250)oC on glass substrates of the thickness(0.8?m). The structure of these films are determined by X-ray diffraction (XRD). The X-ray diffraction studies shows that the structure is polycrystalline with hexagonal structure, and there are strong peaks at the direction (200) at (Ts=RT-150) oC, while at higher substrate temperature(Ts=150-250) oC the structure is single crystal. The optical properties as a function of Ts were studied. The absorption, transmission, and reflection has been studied, The optical energy gap (Eg)increases with increase of substrate temperature from (1.65-1.84)eV due to improvement in the structure. The amorphousity of the films decreases with increasing Ts. The films have direct energy gap and the absorption edge was shift slightly towards smaller wavelength for CdSe:Cu thin film with increase of substrate temperature.it was found that the absorption coefficient was decreased with increasing of substrate temperature due to increases the value of(Eg). The CdSe:Cu films showed absorption coefficient in the range (0.94 x104-0.42x104)cm-1at Ts=RT-250 oC. Also the density of state decreases with increasing of substrate temperatures from (0.20-0.07)eV, it is possibly due to the recrystallization by the heating substrate temperatures.. Also the extinction coefficient, refractive index and dielectric constant have been studied.
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Copper doped Zinc oxide and (n-ZnO / p-Si and n-ZnO: Cu / p-Si) thin films thru thickness (400±20) nm were deposited by thermal evaporation technique onto two substrates. The influence of different Cu percentages (1%,3% and 5%) on ZnO thin film besides hetero junction (ZnO / Si) characteristics were investigated, with X-ray diffractions examination supports ZnO films were poly crystal then hexagonal structural per crystallite size increase from (22.34 to 28.09) nm with increasing Cu ratio. The optical properties display exceptional optically absorptive for 5% Cu dopant with reduced for optically gaps since 3.1 toward 2.7 eV. Hall Effect measurements presented with all films prepared pure and doped have n-types conductive, with a ma
... Show MoreThe gas sensing properties of Co3O4and Co3O4:Y nano structures were investigated. The films were synthesized using the hydrothermal method on a seeded layer. The XRD, SEM analysis and gas sensing properties were investigated for Co3O4and Co3O4:Y thin films. XRD analysis shows that all films are polycrystalline in nature, having a cubic structure, and the crystallite size is (11.7)nm for cobalt oxide and (9.3)nm for the Co3O4:10%Y. The SEM analysis of thin films obviously indicates that Co3O4possesses a nanosphere-like structure and a flower-like structure for Co3O4:Y.The sensitivity, response time and recovery time to a H2S reducing gas were tested at different operating
... Show MoreThe present work focuses on the changing of the structural characteristics of the grown materials through different material characterization methods. Semiconductor CdSxSe 1-x nano crystallines have been synthesized by chemical vapor depostion. (X- ray Diffraction; XRD), (Field Emission Scanning Electron Microscopy; FESEM), measured the characterization of Semiconductor CdSxSe1-x nano crystallines. The optical properties of semiconductor CdSxSe1-x nanocrystallines have been studied by the photoluminescence (PL) (He-Cd pulsed ultraviolet laser at 325nm excitation wavelength) at room temperature. The results showed the change rule of photoluminsence peak at different S
... Show MorePure and doped barium titanate with Mg2+ ion at two molar ratios x= (5%, 10%) mol. has been synthesized by solid state reaction technique. The powders sintered at two temperatures (1000 °C and 1400 °C). An XRD technique was used in order to study the crystal structure of pure and doped barium titanate, which confirmed the formation of the tetragonal phase of BaTiO3, and then calculate the lattice parameters of pure and doped barium titanate, the addition of magnesium ion Mg2+ can lead to decreases lattice parameters.
Pure and doped barium titanate with Mg2+ ion at two molar ratios x= (5%, 10%) mol. has been synthesized by solid state reaction technique. The powders sintered at two temperatures (1000 °C and 1400 °C). An XRD technique was used in order to study the crystal structure of pure and doped barium titanate, which confirmed the formation of the tetragonal phase of BaTiO3, and then calculate the lattice parameters of pure and doped barium titanate, the addition of magnesium ion Mg2+ can lead to decreases lattice parameters.
When a person found himself in a life he did not understand، he tried to create in his imagination powers and gods that tried to protect him from his ignorance of that world، and when he was reassured internally through those fantasy creatures when he made them the greatest protector and the source of his existence and his being، he began to weave myths and myths until he created his reality that he did not have. Any hint، and when we go back to the mechanism of embodying those myths، myths and fantasias in which he lived، we will find that the first building blocks were written on the walls of the caves in which he lived during that period. And when his thought developed and thus his expressive means developed، he began to embody
... Show MoreThe status of the semi total stoppage and non-use and waste of economic made studying and analyzing Dutch disease of high importance because it is a major cause in aggravation of this status which happened to the Iraqi economy in almost complete way and the relative big importance that oil source has and its domination on the largest percentage in the gross domestic product and exports that Iraqi economy is relying largely in funding the national budget made the concentration of the study on this subject an important and necessary within the important economic events that Iraqi economy witnessed after 2003 till 2016 to give a clear and an overall picture of the reality of the unilateral Iraqi economy under the status of semi tota
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