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Abstract: This paper summarizes the first results of characteristics parameters obtained from current–voltage (I–V) measurements for Ag/p-SnS and Ag/p-SnSe structure. The reverse and forward bias current–voltage characteristics of Ag Schottky contacts on a Bridgman–Stockbarger grown p-SnS and p-SnSe layered semiconducting material have been measured at various temperatures. We have tried to determine contact properties such as apparent barrier heights Φ B0, ideality factor n and series resistance R s. The apparent barrier height and ideality factor calculated by using thermionic emission theory were found to be strongly temperature dependent. Evaluating forward I–V data reveals a decrease at the apparent barrier height, but an increase at the ideality factor with decrease in temperature. It is shown that the values of R s estimated from Cheung’s method were strongly temperature dependent and decreased with increasing temperature. It has been found that both contacts are of Schottky type. [Copyright &y& Elsevier]

Abstract: We have fabricated the Al/SnO2/p-Si (111) Schottky diodes having the SnO2/p-Si heterojunction prepared using the spray deposition process at various Si substrate temperatures and report the first investigation of the energy distribution of the interface state density of these diodes. The barrier height Φ B estimated from the I–V and C–V measurements agrees with each other and increased with increasing substrate temperature. The energy distribution of interface state density N ss was determined from the forward bias I–V characteristics by taking into account the bias dependence of the effective barrier height. The interface state density N ss of the diodes has an exponential growth with bias from the midgap towards the top of the valance band for each diode; for example, from 1.46×1012 eV−1 cm−2 in (0.46− E v) eV to 1.29×1012 eV−1 cm−2 in (0.53− E v) eV for SD3 sample. [Copyright &y& Elsevier]

The current–voltage (I–V) measurements on Ag/p-Si Schottky barrier diodes in the temperature range 125–300 K were carried out. The I–V analysis based on the thermionic emission (TE) theory has revealed an abnormal decrease of apparent barrier height and increase of ideality factor at low temperature. It is demonstrated that these anomalies result due to the barrier height inhomogeneities prevailing at the metal–semiconductor interface. A Φb0 versus q/2kT plot was drawn to obtain evidence of a Gaussian distribution of the barrier heights, and values of Φb0=0.780 eV and σs0=0.0906 V for the mean barrier height and standard deviation at zero bias have been obtained from this plot, respectively. Furthermore, the mean barrier height and the Richardson constant values were obtained as 0.773 eV and 15.53 A K-2 cm-2, respectively, by means of the modified Richardson plot, ln(I0/T2)-(q2σs02/2k2T2) versus 1000/T. Thus, it has been concluded that the temperature dependence of the I–V characteristics of the Schottky barrier on p-type Si can be successfully explained on the basis of thermionic emission mechanism with Gaussian distribution of the barrier heights. Moreover, the value of the Richardson constant was found to be 15.53 A K-2 cm-2, which is close to the theoretical value of 32 A K-2 cm-2 used for the determination of the zero-bias barrier height. [Copyright &y& Elsevier]

The current–voltage (I–V) characteristics of Ag/p-SnSe Schottky barrier diodes were measured in the temperature range 80–350 K. We have tried to determine some intrinsic and contact properties such as barrier heights, ideality factor, series resistance and carrier concentrations. The apparent barrier height and the ideality factor calculated by using thermionic emission (TE) theory were found to be strongly temperature dependent. Evaluating forward I–V data reveals a decrease at the zero-bias barrier height (ΦB0), but an increase at the ideality factor (n) with decrease in temperature, and these changes are more pronounced below 200 K. It is shown that the values of Rs estimated from Cheung’s method were strongly temperature dependent and decreased with increasing temperature. From the reverse-bias I–V graphs, it is found that the experimental carrier density (NA) values increased with increasing temperature. The conventional Richardson plot exhibits non-linearity below 200 K with the linear portion corresponding to activation energy of 0.35 eV. It has been found that all contacts are of Schottky type. [Copyright &y& Elsevier]

We have studied the substrate temperature dependence of the series resistance of Al/SnO2/p-Si (1 1 1) Schottky diodes prepared by spray deposition method. Tin oxide films have been deposited on various silicon substrate temperatures (300, 350, 400 and 450 °C) using a spray deposition process. The parameter series resistance Rs, the ideality factor n and the apparent barrier height ΦB0 are determined by performing different plots from the forward current–voltage (I–V) characteristics. We have found that the barrier height increased as the ideality factor decreased with an increase of the substrate temperature. The Rs estimated from Cheung’s method and Lien’s method was increased by increasing the substrate temperature. We have found the suitable series resistance response to the lowest value of ideality factor for the diode prepared at 400 °C (SD3 sample). [Copyright &y& Elsevier]

Abstract: The electrical characterization of the In/p-Si Schottky diode has been investigated by conductance and capacitance–frequency techniques. The characteristic parameters of the interface states have been determined from the capacitance–frequency and conductance–frequency measurements. The capacitance of the In/p-Si Schottky diode decreases with increasing frequency. The increase in capacitance at lower frequencies results from the presence of interface states. The peak observed in the conductance curve of the In/p-Si diode indicates the presence of an interfacial layer in the In/p-Si Schottky barrier. The interface-state parameters, interface-state density D it and relaxation time τ of the In/p-Si diode were calculated. The interface-state density was found to vary from 7.82×1012 eV−1 cm−2 in (0.53−E v)eV to 8.01×1012 eV−1 cm−2 in (0.28−E v)eV. Furthermore, the relaxation time was found to vary from 4.543×10−8 s in (0.53−E v)eV to 4.435×10−8 s in (0.28−E v)eV. [Copyright &y& Elsevier]

Abstract: The space charge-limited conduction mechanism in Ag/p-Si Schottky diode was investigated at range of 175–275K temperatures and detail information about low-temperature conduction mechanism of the Schottky diode could be obtained. Current–voltage characteristics and the power-law dependence was found to be governed by space charge-limited currents. In this conduction mechanism, the current increases superlinearly in the diode , i.e, . The I–V curves in the reverse direction at different temperatures are taken and interpreted via both Schottky and Poole–Frenkel effects. Poole–Frenkel effect was found to be dominant in the reverse direction. The density of localized states was determined, as well through the SCLC theory. [Copyright &y& Elsevier]