Diamond-like carbon (DLC) homogeneous thin films were deposited from cyclohexane (Ccyclohexane (Ccyclohexane (Ccyclohexane (C cyclohexane (Ccyclohexane (Ccyclohexane (C cyclohexane (Ccyclohexane (C 6H12 ) liquid by using a plasma jet system which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 kv and kv and kv and kv and frequency 28 frequency 28frequency 28 frequency 28frequency 28frequency 28frequency 28frequency 28 kHz. kHz. The optical and structural properties and chemical bonding of these films were investigated. In this work, the effect of changing the distance between the substrate and the plasma torch (2, 2.5 and 3 cm) was studied. The flow rate of argon gas which used to generate the plasma was fixed (0.5 L/min). These films were characterized by UV–Visible spectrophotometer, X-ray diffractometer (XRD) and scanning electron microscopy (SEM) and Fourier transformation infrared spectroscopy (FTIR). The maximum absorption (λmax) appears around 312, 298.3 and 293.2 nm at the three distance between plasma torch and the substrate 2.5, 2 and 3 cm, respectively. The values of the optical energy gap are 3.47, 3.65 and 3.76 eV at a different distance (2, 2.5 and 3cm), respectively. In XRD diffraction pattern, The occurrence of diamond peaks and graphite peaks in the x-ray spectrum for these films Indicates that there is an occurrence of local ordered sp3 and sp2 for carbon domains and graphite respectively.
In this research, the structural and optical measurements were made on the Zinc oxide (ZnO) films prepared by two methods once by using chemical spray pyrolysis technique, and another by using thermal evaporation technique before and after irradiation by Gamma –Ray (γ – rays) from source type (Cs 137) with an energy (0.611)MeV as a function of gamma dose (0.15,0.3 and 0.45) Gy. The thickness of all films prepared by two method was about (300 ± 50) nm. XRD is used to characterize the structural properties, the results demonstrated that all samples prepared by two method before and after irradiation have polycrystalline structure with a preferred orientation (002).Also it showed that the structural properties are weakly
... Show MoreThis paper presents the effect of Cr doping on the optical and structural properties of TiO2 films synthesized by sol-gel and deposited by the dip- coating technique. The characteristics of pure and Cr-doped TiO2 were studied by absorption and X-ray diffraction measurement. The spectrum of UV absorption of TiO2 chromium concentrations indicates a red shift; therefore, the energy gap decreases with increased doping. The minimum value of energy gap (2.5 eV) is found at concentration of 4 %. XRD measurements show that the anatase phase is shown for all thin films. Surface morphology measurement by atomic force microscope (AFM) showed that the roughness of thin films decrease with doping and has a minimum value with 4 wt % doping ratio.
Nano-structural of vanadium pentoxide (V2O5) thin films were
deposited by chemical spray pyrolysis technique (CSPT). Nd and Ce
doped vanadium oxide films were prepared, adding Neodymium
chloride (NdCl3) and ceric sulfate (Ce(SO4)2) of 3% in separate
solution. These precursor solutions were used to deposit un-doped
V2O5 and doped with Nd and Ce films on the p-type Si (111) and
glass substrate at 250°C. The structural, optical and electrical
properties were investigated. The X-ray diffraction study revealed a
polycrystalline nature of the orthorhombic structure with the
preferred orientation of (010) with nano-grains. Atomic force
microscopy (AFM) was used to characterize the morphology of the
films. Un-do
Thin films of Zinc Selenide ZnSe have been prepared by using thermal evaporation in vacuum technique (10-5Torr) with thickness (1000, 2700, 4000) A0 and change electrode material and deposited on glass substrates with temperature (373K) and study some electrical properties at this temperature . The graphs shows linear relation between current and voltage and the results have shown increases in the value of current and electrical conductivity with increase thickness and change electrode material from Aluminum to Copper
The influence of silver doped n-type polycrystalline CdTe film with thickness of 200 nm and rate deposition of 0.3 nm.s -1 prepared under high vacuum using thermal co-evaporation technique on its some structural and electrical properties was reported. The X- ray analysis showed that all samples are polycrystalline and have the cubic zinc blend structure with preferential orientation in the [111] direction. Films doping with impurity percentages (2, 3, and 4) %Ag lead to a significant increase in the carrier concentration, so it is found to change from 23.493 108 cm -3 to 59.297 108 cm -3 for pure and doped CdTe thin films with 4%Ag respectively. But films doping with impurity percentages above lead to a significant decrease in the electrica
... Show MoreIndium doped CdTe polycrystalline films of thickness equals to 300nm were grown on corning glass substrates at temperature equals to 423K by thermal co-evaporation technique. The structural and electrical properties for these films were studied as a function of heat treatment (323,373,423)K. The x-ray analysis showed that all samples are polycrystalline and have the cubic zincblende structure with preferential orientation in the [111] direction, no diffraction peaks corresponding to metallic Cd, Te or other compounds were observed. It was found that the electrical resistivity drops and the carrier concentration increases when the CdTe film doped with 1.5% indium and treated at different annealing temperatures.
Compounds from ZnO doped with AgO in different ratio (0,3,5,7, and 9)wt.% were prepared.Thin films from the prepared compounds were deposited on a glass substrate using the pulsed laser deposition method. The XRD pattern confirmed the presence of a single-phase hexagonal wurtzite ZnO structure, without the presence of a secondary phase. AFM measurements showed an increase in both average grain size and average surface roughness with increasing concentration content of (AgO).The crystallite size of ZnO of the main peak corresponding to the preferred plane of crystal growth named (100) increases from 17.8 to 22.5nm by increasing of AgO doping ratio from 0 to 9%. The absorbance and transmittance in the wavelength range (350-1100 nm) were
... Show MoreIn this research , the structural and optical properties of pure of cadmium oxide, pure (CdO) were studided thin films in a thermal evaporation in a vacuum depositing metal cadmium pure rules of the glass at room temperature (300K) and thickness (300 ± 20nm) and the time of deposition (1.25sec) was oxidation of thin films cadmium (Cd) record temperature (673k) for a period of one hour to the presence of air optical energy gap for direct electronic transitions were calculated (permitted) as a function of absorption coefficient and permeability and reversibility by recording the spectrum absorbance and permeability of the membrane the record
... Show MoreAlO-doped ZnO nanocrystalline thin films from with nano crystallite size in the range (19-15 nm) were fabricated by pulsed laser deposition technique. The reduction of crystallite size by increasing of doping ratio shift the bandgap to IR region the optical band gap decreases in a consistent manner, from 3.21to 2.1 eV by increasing AlO doping ratio from 0 to 7wt% but then returns to grow up to 3.21 eV by a further increase the doping ratio. The bandgap increment obtained for 9% AlO dopant concentration can be clarified in terms of the Burstein–Moss effect whereas the aluminum donor atom increased the carrier's concentration which in turn shifts the Fermi level and widened the bandgap (blue-shift). The engineering of the bandgap by low
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