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Gallium doped cadmium-oxide (CdO: Ga) thin films were successfully deposited by sol-gel spin coating method on p-type Si substrate. The electrical properties of the photodiode based on nanostructure Ga doped n-CdO/ p-Si junctions were investigated. The current-voltage ( I- V) characteristics of the structure were investigated under various light intensity and dark. It was observed that generated photocurrent of the Au/ n-CdO/p-Si junctions depended on light intensity. The capacitance-voltage and conductance-voltage measurements were carried out for this diode in the frequency range between 100 and 1000 kHz at room temperature by steps of 100 kHz. The capacitance decreased with increasing frequency due to a continuous distribution of the interface states. These results suggested that the Au/ n-CdO/ p-Si Schottky junctions could be utilized as a photosensor. Furthermore, the voltage and frequency dependence of series resistance were calculated from the C- V and G/ω-V measurements and plotted as functions of voltage and frequency. The distribution profile of R - V gave a peak in the depletion region at low frequencies and disappeared with increasing frequencies. [ABSTRACT FROM AUTHOR]

We have investigated the electrical properties and current transport mechanisms of W/ p-InP Schottky diode using current-voltage ( I- V), capacitance-voltage-frequency ( C- V- f) and conductance-frequency ( G- f) techniques at room temperature. The W/ p-InP Schottky diode exhibits a good rectifying behavior. Measurements show that the Schottky barrier height (SBH) and ideality factor of the W/ p-InP Schottky diode are 0.84 eV ( I- V)/0.98 eV ( C- V) and 1.24, respectively. Also, the SBH and series resistance R of the diode are extracted by Cheung's functions and the values are in good agreement with each other. Ohmic and space charge-limited conduction mechanisms are found to govern the current flow in the W/ p-InP Schottky diode at low and high forward bias conditions, respectively. Experimental results reveal that the Poole-Frenkel mechanism is found to be dominant in the reverse bias region of W/ p-InP Schottky diode. Further, the interface state density N and their relaxation times τ of the W/ p-InP Schottky diode are estimated from the forward bias C- f and G- f characteristics and the values are in the range from 1.95 × 10 eV cm and 3.38 × 10 s at (0.81- E) eV to 1.78 × 10 eV cm and 2.78 × 10 s at (0.30- E) eV, respectively. Both the N and τ show an exponential rise with bias from the top of the valance band toward the mid gap. [ABSTRACT FROM AUTHOR]

Theoretical investigations of Cr doped GaAs in zinc blende phase are presented in this paper. The robustness of half metallicity of these compounds with correlation to their lattice compressions is discussed. Shifting of Fermi Level with compression of lattice constant is also addressed in this article. Results show that compounds exhibit their half-metallic nature (conductor for spin up state and semiconductor for spin down state) with their lattice compressions up to certain critical lattice constants. Abrupt changes in electronic and magnetic properties are observed for these robust transition lattice constants (RTLCs). These compounds lose their integer magnetic moments 4μ at RTLCs. Calculated RTLC for GaCrAs is 5.03 Å. Possible compressions in lattice constants from their relaxed states while maintaining their half-metallic nature is up to 4 %. [ABSTRACT FROM AUTHOR]

Conducting polyaniline (PANI) was prepared by chemical oxidation polymerization in the presence of excess hydrochloric acid. Zinc sulfide (ZnS) thin films were deposited on glass substrates at the pressure of 10 mbar by thermal resistor evaporation technique. The solution of conducting PANI has been printed on pellet of ZnS using spin-coating technique. I- V characteristics of ZnS thin film and printed conducting PANI have been recorded at room temperature. The results indicated that I- V of conducting PANI shows non-ohmic behavior and I- V characteristic of conducting PANI printed ZnS, a PANI-ZnS heterojunction, shows the rectification effect and confirms that a diode can be fabricated by using simple technique. [ABSTRACT FROM AUTHOR]