الفهرس 
Introduction of Nanotechnology and Aim of the WorkOnly 14 pages are availabe for public view
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Abstract
Organic semiconductors are particularly attractive as active materials used in electronic and optoelectronic devices due to their excellent electrical properties and ease of preparation .They have also been used to fabricate electronic devices such as transistors, light emitting diodes and solar cells.
Conjugated polymers like Poly(3,4-ethylenedioxythiophene) (PEDOT) and their derivatives have been known to have defined electronic properties among the conjugated polymers. A large number of Schottky barrier diodes (SBDs) have been fabricated and characterized using organic conductive polymers together with metals. Over the last two decades, substantial research studies have been made on the preparation and characterization of conducting polymer/inorganic semiconductor heterojunction.
Poly(3,4-ethylenedioxythiophene), Tetra Methacrylate (PEDOTTM ) has attracted considerable attention due to its excellent environmental stability, low oxidation potential and high electrical conductivity as well as its good electro chromic.
This work presents the synthesis, characterization and properties of PEDOTTM doped with TiO2 and ZnO nanoparticles with their applications. The effect of adding titanium dioxide (TiO2) and zinc oxide (ZnO) nanoparticles by using the direct method on the electrical and optical properties of PEDOTTM /n-Si heterojunction will be outlined. The prepared samples will be analyzed by X-ray diffraction (XRD), transmission and scanning electron microscopy (TEM&SEM) .Also, with the fourier transform infrared spectroscopy (FTIR).
PEDOTTM/n-Si heterojunction will be fabricated by deposition of PEDOTTM (p-type) thin films using the thermal evaporation method onto n-type Si single crystals. The dependence of the current density-voltage (J-V) characteristics on the temperature in both forward and reverse bias will be investigated according to thermionic emission model to obtain information on the transport mechanisms of the devices.
The J-V characteristics in exponential region which depends on the ideality factor (n) and saturation current (Js) will be presented. n gives information about the recombination behavior in the diode, and the shape of the interface, i.e. the internal bulk morphology. Js reflects the number of charge carriers able to overcome the energetic barrier in the reverse bias.
Jonsher and Hill relations will be used to find the proper mechanism to explain the behavior of the observed J-V characteristics in the device which can be explained in terms of the charge transport mechanism operating in the device at the different voltage ranges.
For the optical properties, PEDOTTM thin films were deposited onto glass substrates via spin-coating technique at speed about 800-1000 rpm with different thicknesses (220 nm and 300 nm).
The transmittance (T (λ)) and reflectance (R (λ)) spectra of the thin films will be measured at normal incidence and room temperature in the spectral range of 200-2500 nm. Also, the optical band gap (Eg) and optical constants as refractive index (n) and the extinction coefficient (k) will be presented. Both are an important parameter reflecting the optical quality of PEDOTTM thin films.
The real (ε1) and imaginary (ε2) parts of the optical dielectric constants will be outlined with the real and imaginary parts of the optical conductivity (Ϭ1 and Ϭ2 respectively).