الفهرس 
Introduction and theoretical backgroundOnly 14 pages are availabe for public view
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Abstract
The aim of this thesis is to study the physical properties of an organic compound, especially in the form of thin films, in order to manufacture solar cells with inorganic semiconductors.
Toluidine Blue (TB) thin films has been prepared by the conventional thermal evaporation technique. The structural, optical, electrical and photovoltaic properties of the films have been investigated. The structural properties of the films have been studied by using the differential scanning calorimeter (DSC), X-ray diffraction (XRD) and Fourier transforms infrared spectroscopy (FTIR) techniques. The structural analysis show that TB thin films are of as amorphous structure in pristine, annealing temperatures, γ-ray and UV irradiation. The infrared absorption spectroscopy gave evidence about stability of the molecular structure of TB compound for annealing temperatures, γ-ray, UV irradiation and thermal deposition.
Optical absorption parameters of the TB films have been calculated using band to band electron transition theory. We have applied the single oscillator model for calculating all of the dispersion and dielectric parameters for TB films. Dispersion and dielectric parameters of TB films have been calculated by applying single oscillator model. The onset and optical energy gaps is found to be 1.38 and 2.95 eV, respectively. These results clarify that the annealing and irradiation has not affected both the type of electron transition and the values of the energy gaps.
The frequency and temperature dependence of the AC conductivity σAC, the real part of the dielectric constant, the imaginary part of the dielectric constant, and the dielectric modulus are investigated in the temperature range 303- 453 K and in the frequency range 0.2 - 3500 kHz. The ac conductivity is found to follow Jonscher’s universal power law . Additionally, the dielectric constants are found to increase by increasing the temperatures which involve distribution of relaxation times. Further, the temperature dependent exponent s outweighs the correlated barrier hopping (CBH) model for conduction mechanism.
Toluidine Blue (TB)/n-silicon heterojunction solar cell was fabricated by depositing TB film on n-silicon wafer using thermal deposition technique. The current-voltage- temperature performance of Au/TB/n-Si/Al device was studied in dark and under illumination conditions. The device showed diode behavior. The diode parameters such as ideality factor, barrier height, series and shunt resistance were determined using a conventional I-V-T characteristics. The analysis of the diode characteristics in forward bias direction confirmed that the transport mechanisms of the Au/TB/n-Si/Al solar cell at applied potential < 0.1 V is thermionic emission and at high electric field > 0.1 V is Ohmic conduction. The Au/TB/n-Si/Al hybrid solar cell under illumination with light of intensity 20 mW/cm2 has the following photovoltaic parameters as: 0.186 V for the open circuit voltage (Voc), 1.15 mA for short circuit current (Isc), 0.34 for fill factor (FF) and 1.45% for power conversion efficiency (η).