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Abstract: The temperature dependence of current–voltage (I–V) characteristics of the Au/Pyronine-B/moderately doped (MD) n-InP Schottky barrier diode has been systematically investigated in the temperature range of 160–400K. Modification of the interfacial potential barrier for metal/InP diodes has been achieved using a thin interlayer of the pyronine B organic semiconductor. It has been observed that ideality factor n (=1.10) remained close to ideal limit while barrier height of Au/Pyronine-B/n-InP structure increased about 0.180eV with respect to Au/n-InP in the previous study, at room temperature. The forward I–V characteristics have been interpreted on the basis of standard thermionic emission (TE) theory and assumption of a Gaussian distribution of the barrier height. The apparent barrier height and the ideality factor derived by using thermionic emission theory have been found to be strongly temperature dependent. That is, it has been understood that the ideality factor decreases while the apparent barrier height increases with increasing temperature. It has been shown that the conventional ln(J 0/T 2) vs. 1000/T plot exhibits a non-linearity below 240K. It has been demonstrated that this behaviour results due to the barrier height inhomogeneities prevailing at the metal–semiconductor interface. The mean barrier height and the Richardson constant (A*) values were obtained as 0.961eV and 17.73AK−2 cm−2, respectively, by means of the modified Richardson plot, vs. 1/T. The value of Richardson constant A* obtained from this plot is close to the theoretical value of 9.4AK−2 cm−2 for n-InP. As a result, it can be concluded that the temperature dependent characteristic parameters for Au/Pyronine-B/MD n-InP structure can be succesfully explained on the basis of TE mechanism with Gaussian distribution of the barrier height. [Copyright &y& Elsevier]

Abstract: The temperature dependent barrier characteristics of Ag/p-GaSe Schottky barrier diodes have been analyzed in the temperature range of 70–350K based on thermionic emission (TE) theory. Barrier height (BH) (φ b0), ideality factor (n) and serial resistance (R s) have been found to be strongly temperature dependent. Decrease in the φ b0 and an increase in the n with decrease in temperature has been observed. The conventional Richardson plot exhibits non-linearity below 180K with the linear portion corresponding to activation energy of 0.62eV. The value of Richardson constant (A*) turns out to be 5.15×10−4 AK−2 cm−2 against the theoretical value of 60AK−2 cm−2 for p-GaSe. It has been demonstrated that these behaviors result from the spatial BH inhomogeneities prevailing at the metal–semiconductor interface. For the interpretation of the BH inhomogeneity, multiple Gaussian distribution model developed by Jiang et al. has been used. Furthermore, an expression defining temperature dependent ideality factor has been derived for the diodes with spatial BH inhomogeneities considering multiple Gaussian distribution. The temperature dependent BH of the device has shown a Double Gaussian Distribution (DGD) having mean BH of 1.21 and 1.08eV with standard deviations (σ 0) of 0.103 and 0.097eV in the 180–350 and 70–180K regions, respectively. and A* values have also been obtained as 1.209eV, 62.8AK−2 cm−2 and 1.097eV, 56.8AK−2 cm−2 from the modified Richardson plots for the respective temperature regions, respectively. These values of A* are in close agreement with that of the known value for p-type GaSe. It has been shown that these results support the predictions of the multiple GD model of spatial BH inhomogeneities in the temperature range of 70–350K. [Copyright &y& Elsevier]

Abstract: The temperature dependences of current–voltage (I–V) and capacitance–voltage (C–V) characteristics of the gold Schottky contacts on moderately doped n-InP (Au/MD n-InP) Schottky barrier diodes (SBDs) have been systematically investigated in the temperature range of 60–300K. The main diode parameters, ideality factor (n) and zero-bias barrier height (apparent barrier height) were found to be strongly temperature dependent and while the decreases, the n and the increase with decreasing temperature. According to Thermionic Emission (TE) theory, the slope of the conventional Richardson plot [In(J 0/T 2) vs. 1000/T] should give the barrier height. However, the experimental data obtained do not correlate well with a straight line below 160K. This behaviour has been interpreted on the basis of standard TE theory and the assumption of a Gaussian distribution of the barrier heights due to barrier inhomogeneities that persist at the metal-semiconductor interface. The linearity of the apparent barrier height vs. 1/(2kT) plot that yields a mean barrier height of 0.526eV and a standard deviation (σ s0) of 0.06eV, was interpreted as an evidence to apply the Gaussian distribution of the barrier height. Furthermore, modified Richardson plot [ vs. 1/T] has a good linearity over the investigated temperature range and gives the and the Richardson constant (A ∗) values as 0.532eV and 15.90 AK−2cm−2, respectively. The mean barrier heights obtained from both plots are appropriate with each other and the value of A ∗ obtained from the modified Richardson plot is close to the theoretical value of 9.4AK−2cm−2 for n-InP. From the C–V characteristics, measured at 1MHz, the capacitance was determined to increase with increasing temperature. C–V measurements have resulted in higher barrier heights than those obtained from I–V measurements. The discrepancy between Schottky barrier heights(SBHs) obtained from I–V and C–V measurements was also interpreted. As a result, it can be concluded that the temperature dependent characteristic parameters for Au/MD n-InP SBDs can be successfully explained on the basis of TE mechanism with Gaussian distribution of the barrier heights. [Copyright &y& Elsevier]

The electrical properties of Schottky contact with a quadripartite alloy FeCrNiC on p -Si have been investigated in the temperature range of 80–320 K, for the first time. An abnormal decrease in the apparent barrier height ( φ ap. ) and an increase in the apparent ideality factor ( n ap. ) with a decrease in the temperature were elucidated by the current–voltage ( I – V ) characteristic of the FeCrNiC/ p -Si structure. The conventional Richardson plot exhibits non-linear behaviour at temperature below 180 K with the linear portion to be used for the calculation of activation energy and Richardson constant ( A *) as 0.352 eV and 8.3 × 10 −3 A K −2 cm −2 , respectively. The observed anomalies were explained on the basis of the thermionic emission (TE) theory by incorporating the concept of inhomogeneous multiple barriers at Metal–Semiconductor (MS) interface. It has been seen that the apparent barrier height φ ap. exhibits double Gaussian distribution (DGD) feature with the mean BH ( ϕ ¯ b 0 ) of 0.695 and 0.646 eV, accompanied by their standard deviations ( σ 0 ) of 0.082 and 0.070 eV in 320–180 K and 180–80 K regions, respectively. These values of the ϕ ¯ b 0 have been confirmed with the modified Richardson plot [ ln ( J 0 / T 2 ) − ( q 2 σ 0 2 / 2 k 2 T 2 )     vs .     1 / T ] as 0.690 eV and 0.633 eV at the demarcated temperature regions, respectively. Richardson constant A * has also been calculated from the modified Richardson plots as 33.43 A K −2 cm −2 and 28.47 A K −2 cm −2 that belong to two distinct temperature ranges. Their average value exactly matched the theoretical value of 31.6 A K −2 cm −2 for the holes in p -type Si. Our results confirm the predictions of the multiple GD approach of nanoscale spatial BH inhomogeneities at the MS interface. [ABSTRACT FROM AUTHOR]