Thin films of microcrystalline and nanocrystalline -silicon carbide and silicon, where deposited on glass substrate with substrate temperature ranging from 350-400C, with deposition rate 0.5nm per pulse, by laser induced chemical vapor deposition. The deposition induced by TEACO2 laser. The reactant gases (SiH4 and C2H4) photo decompose throughout collision associated multiple photon dissociate. Such inhomogeneous film structure containing crystalline silicon, silicon carbide and amorphous silicon carbide matrix, give rise to a new type of material nanocrystalline silicon carbide in which the optical transmittance is governed by amorphous SiC phase while nanocrystalline grain are responsible for the conduction processes. This new material is promised for many new applications, lick high efficiency solar cell.
X-ray diffraction patterns and scanning microscope images revealed that nanocrystalline SiC and Si films grew at substrate temperature above 400C, while completely amorphous films grew at substrate temperature 350C.
Cadmium oxide thin films were prepared by D.C magnetron plasma sputtering using different voltages (700, 800, 900, 1000, 1100 and 1200) Volt. The Cadmium oxide structural properties using XRD analysis for just a voltage of 1200 volt at room temperature after annealing in different temperatures (523 and 623) K were studied .The results show that the films prepared at room temperature have some peaks belong to cadmium element along the directions (002), (100), (102) and (103) while the other peaks along the directions of (111), (200) and (222) belong to cadmium oxide. Annealed samples display only cadmium oxide peaks. Also, the spectroscopic properties of plasma diagnostic for CdO thin films were determined and the results show that the el
... Show MoreTin Selenide (SnSe) Nano crystalline thin films of thickness 400±20 nm were deposited on glass substrate by thermal evaporation technique at R.T under a vacuum of ∼ 2 × 10− 5 mbar to study the effect of annealing temperatures (as-deposited, 100, 150 and 200) °C on its structural, surface morphology and optical properties. The films structure was characterized using X-ray diffraction (XRD) which showed that all the films have polycrystalline in nature and orthorhombic structure, with the preferred orientation along the (111) plane. These films was synthesized of very fine crystallites size of (14.8-24.5) nm, the effect of annealing temperatures on the cell parameters, crystallite size and dislocation density were observed.
... Show MoreThin films of BhSe3 have being deposited on glass substrates of
about 80 - 172 ± 14 nm thickness from an aqueous solution bath at temperature 293 K for period 0.5 to 6.0 hours using alchemical bath deposition method .
The films are characterized by X-ray diffraction, X-ray
florescent techniques and optical transmittance spectra measurements in the rang 350 - 400 nm at 293 K. And shows that as deposited films are amorphous and a transition to polycrystalline state has taken place after annealing them at 373 K, for 30 minutes, But they will be dan1aged
... Show MoreIn this research, we study the changing structural properties of ZnO with changing annealing temp., in the range (473-773)K prepared by chemical bath deposition method at temp. (353)K, where deposited on glasses substrates at thickness (500±25)nm, the investigation of (XRD) indicates that the (ZnO) films are polycrystalline type of Hexagonal.
The results of the measuring of each sample from grain size, microstrain, dislocation density, integral breadth, shape factor and texture coefficient, show that annealing process leads to increase the grain size (26.74-57.96)nm, and decrease microstrain (0.130-0.01478), dislocation density (1.398-0.297)*1015
... Show MoreIn this work, plasma parameters such as (electron temperature (Te), electron density (ne), plasma frequency (fp) and Debye length (λD)) were studied using spectral analysis techniques. The spectrum of the plasma was recorded with different energy values, SnO2 and ZnO anesthetized at a different ratio (X = 0.2, 0.4 and 0.6) were recorded. Spectral study of this mixing in the air. The results showed electron density and electron temperature increase in zinc oxide: tin oxide alloy targets. It was located that The intensity of the lines increases in different laser peak powers when the laser peak power increases and then decreases when the force continues to increase.
In this work, plasma parameters such as, the electron temperature )Te(, electron density ne, plasma frequency )fp(, Debye length )λD(
and Debye number )ND), have been studied using optical emission spectroscopy technique. The spectrum of plasma with different values of energy, Pb doped CuO at different percentage (X=0.6, 0.7, 0.8) were recorded. The spectroscopic study for these mixing under vacuum with pressure down to P=2.5×10-2 mbar. The results of electron temperature for X=0.6 range (1.072-1.166) eV, for X=0.7 the Te range (1.024-0.855) eV and X=0.8 the Te is (1.033-0.921) eV. Optical properties of CuO:Pb thin films were determined through the optical transmission method using ultraviolet visible spectrophotometer within the ra
In this article, the influence of group nano transition metal oxides such as {(MnO2), (Fe2O3) and (CuO)} thin films on the (ZnO-TiO2) electric characteristics have been analyzed. The prepared films deposited on glass substrate laser Nd-YAG with wavelength (ℷ =1064 nm) ,energy of (800mJ) and number of shots (400). The density of the film was found to be (200 nm) at room temperature (RT) and annealing temperature (573K).Using DC Conductivity and Hall Effect, we obtained the electrical properties of the films. The DC Conductivity shows that that the activation energies decrease while the σRT at annealing temperature with different elements increases the formation of mixed oxides. The Hall effect, the elec
... Show MoreImprovement of optoelectrical characteristics of phosphorus diffused silicon photodiodes by Q-switched Nd:YAG laser pulses was investigated. Laser pulses have dissolved the precipitation of phosphorus resulted during thermal diffusion process. The experimental data show that responsivity higher than (0.32 A/W) at 850 nm can be achieved after laser annealing with (1.5 MW/cm2) for 6 shots.
Porous silicon (P-Si) has been produced in this work by photoelectrochemical (PEC) etching process. The irradiation has been achieved using diode laser of (2 W) power and 810 nm wavelength. The influence of various irradiation times on the properties of P-Si material such as P-Si layer thickness, surface aspect, pore diameter and the thickness of walls between pores as well as porosity and etching rate was investigated by depending on the scanning electron micrograph (SEM) technique and gravimetric measurements.