The current-voltage (I-V ) characteristics of Cd/p-GaTe Schottky barrier diodes were measured in the temperature range 90-330 K. The apparent barrier height and the ideality factor derived by using thermionic emission (TE) theory were found to be strongly temperature dependent. Evaluating forward I-V data reveals a decrease of zero-bias barrier height ( b0 ) but an increase of ideality factor (n) with decrease in temperature, and these changes are more pronounced below 150 K. The conventional Richardson plot exhibits nonlinearity below 150 K with the linear portion corresponding to an activation energy of 0.52 eV. The value of effective Richardson constant (A * ) turns out to be 6.74 × 10 −2 A K −2 cm −2 against the theoretical value of 119.4 A K −2 cm −2 . It is demonstrated that the findings cannot be explained on the basis of tunnelling and image force lowering effects. Also, the concept of the flat-band barrier height f b fails to account for the temperature dependence of the diode parameters. Finally, it is demonstrated that these anomalies result due to the barrier height inhomogeneities prevailing at the metal-semiconductor interface. The inhomogeneities are considered to have Gaussian distribution with a mean barrier height of ¯ b0 = 0.886 eV and a standard deviation of σ s0 = 0.091 eV at zero bias. Furthermore, the mean barrier height and the Richardson constant values were obtained as 0.875 eV and 62.2 A K −2 cm −2 , respectively, by means of the modified Richardson plot, ln(J 0 /T 2 ) − q 2 σ 2 s0 /2k 2 T 2 versus 1000/T. Hence, it has been concluded that the temperature dependence of the I -V characteristics of the Schottky barrier on p-type GaTe can be successfully explained on the basis of TE mechanism with Gaussian distribution of the barrier heights.

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High quality sandwich device was fabricated from wheat DNA molecular film by solution processing located between Au and n-type silicon inorganic semiconductor. We have performed the electrical characteristics of the device such as current–voltage (I–V) and capacitance–voltage (C–V) at room temperature. DNA-based on this structure showed an excellent rectifying behavior with a typical ideality factor of 1.22, and that DNA film increased the effective barrier height by influencing the space charge region of Si. We proposed that DNA could be an insulatorlike material with a wide optical band energy gap of 4.19 eV from its optical absorbance characteristics. Additionally, the energy distribution of interface state density, determined from the forward bias I–V characteristics by taking into account the bias dependence of the effective barrier height, decreases exponentially with bias from 7.48×1015 m−2 eV−1 in (Ec−0.40) eV to 8.56×1014 m−2 eV−1 in (Ec−0.72) eV.

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Au/n-GaAs Schottky barrier diodes SBDs have been fabricated. Schottky diode parameters such as the ideality factor, the series resistance, and the Schottky barrier height ͑SBH͒, ⌽ b , have been measured as a function of hydrostatic pressure using the current-voltage (I-V) technique. We have seen that the SBH has a linear pressure coefficient of 11.21 meV/kbar ͑ϭ112.1 meV/GPa͒. Also, the series resistance value increases with increasing pressure. We have concluded that the variation of the barrier height due to the applied pressure should follow precisely the variation of the semiconductor band gap, accepting that the Fermi level is a reference level which is pinned to the valance-band maximum as a function of the pressure. That is, we have concluded that the experimental results is in agreement with the model that the pressure coefficient is caused by the pressure coefficient of the direct midgap level.

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We investigated Schottky barrier diodes of 9 metals (Mn, Cd, Al, Bi, Pb, Sn, Sb, Fe, and Ni) having different metal work functions to p-type Si using current-voltage characteristics. Most Schottky contacts show good characteristics with an ideality factor range from 1.057 to 1.831. Based on our measurements for p-type Si, the barrier heights and metal work functions show a linear relationship of current-voltage characteristics at room temperature with a slope (S=ϕ

Nanostructured TiO 2 thin films were deposited on quartz glass at room temperature by sol-gel dip coating method. The effects of annealing temperature between 200 • C to 1100 • C were investigated on the structural, morphological, and optical properties of these films. The X-ray diffraction results showed that nanostructured TiO 2 thin film annealed at between 200 • C to 600 • C was amorphous transformed into the anatase phase at 700 • C, and further into rutile phase at 1000 • C. The crystallite size of TiO 2 thin films was increased with increasing annealing temperature. From atomic force microscopy images it was confirmed that the microstructure of annealed thin films changed from column to nubbly. Besides, surface roughness of the thin films increases from 1.82 to 5.20 nm, and at the same time, average grain size as well grows up from about 39 to 313 nm with increase of the annealing temperature. The transmittance of the thin films annealed at 1000 and 1100 • C was reduced significantly in the wavelength range of about 300-700 nm due to the change of crystallite phase. Refractive index and optical high dielectric constant of the n-TiO 2 thin films were increased with increasing annealing temperature, and the film thickness and the optical band gap of nanostructured TiO 2 thin films were decreased.