ZnO thin films deposited on various substrates including glass, quartz, and ITO (Indium Tin Oxide) coated on glass substrates have been conducted by (CSP) technique. Characterization techniques of X-ray diffraction (XRD), atomic force microscopy (AFM), UVvisible, and photoluminescence (PL) spectra measurements were performed to investigate the effects of substrate on the structural and optical properties of ZnO thin films. Samples were prepared the thickness of thin films are (80 nm) and substrate temperature kept at (400°C) in all cases. Compressed nitrogen was used as a carrier gas. The XRD results indicated that the synthesized ZnO thin films have a pure wurtzite (hexagonal phase) structure. It can be seen that the highest texture coefficient was in (002) plane . So when a good crystalline substrate like quartz is used for depositing the film, the lattice matching with the deposited film material would be better. AFM measurement showed the grain size ranging from (62-86) nm. The optical studies showed that the thin film for ITO coated glass substrate higher transmittance than glass and quartz substrate. The optical band gap for ZnO thin films have two values for the same sample, and we will note the band gap of the thin films increasing with increase the crystalline of substrate. The energy gap from photoluminescence (PL) spectra is (3.369 eV) for all samples.

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ZnO thin films deposited on various substrates including glass, quartz, and ITO (Indium Tin Oxide) coated on glass substrates have been conducted by (CSP) technique. Characterization techniques of X-ray diffraction (XRD), atomic force microscopy (AFM), UV-visible, and photoluminescence (PL) spectra measurements were performed to investigate the effects of substrate on the structural and optical properties of ZnO thin films. Samples were prepared the thickness of thin films are (80 nm) and substrate temperature kept at (400oC) in all cases. Compressed nitrogen was used as a carrier gas. The XRD results indicated that the synthesized ZnO thin films have a pure wurtzite (hexagonal phase) structure. It can be seen that the highest texture coefficient was in (002) plane . So when a good crystalline substrate like quartz is used for depositing the film, the lattice matching with the deposited film material would be better. AFM measurement showed the grain size ranging from (62-86) nm. The optical studies showed that the thin film for ITO coated glass substrate higher transmittance than glass and quartz substrate. The optical band gap for ZnO thin films have two values for the same sample, and we will note the band gap of the thin films increasing with increase the crystalline of substrate. The energy gap from photoluminescence (PL) spectra is (3.369 eV) for all samples.

In this paper porous silicon sample that can be used as a photodetector was prepared at fixed etching time of 15min and different etching current density (15, 17, 19 and 21) mA/cm 2 . Electrical properties of Al / PSi / p-Si /Al photodetector were studied. We found that the I-V characteristics dependence of the etching current density relates to the PSi pores development, where the pore diameter in PSi structure might get enlarged due to the enhancement of the etching current density. The ideality factor ranges around (6.8-4.2) while the barrier height decreased with the increasing etching current density and the etching time as the interface layer between PSi/c-Si has large amount of pinning. Then the C-V characteristics of the sandwich structure are described. When the etching current densities are increased, it reduces the capacitance of the PSi layer. It thus increases the thickness of the depletion region which in turn results in development of built-in potential.

The study includes the recording the absorption and permeability spectra of a combination of polyaniline compound solution with poly(3,4-ethylenedioxythiophene) PEDOT and calculating the absorption factor and other optical constants. These samples were attended to different concentrations (0.01%,0.02%,0.03%) of PEDOT added to polyaniline. The values of absorbance, the refractive index values of pure polymer and its additives are increasing with the increase of the concentrations of these polymer,noting that the increment of absorption coefficient values under the influence of addition caused by increasing density of the solutions as a result of the increased concentrations, that led to the increase of light absorbed because the interaction of the electromagnetic wave and the large molecules of the polymer increases with concentration,the results show that decreasing in the values of transmittance with all concentrations, the values of reflectance are increases with increasing concentration before and after the doping, the results showed decrease energy gap with increasing ratio of doping.