Analysis of temperature dependent current-voltage characteristics of Sn/p-GaTe/In Schottky diode

Abstract

In present study, Sn/p-GaTe/In Schottky diode is fabricated using thermal evaporation method. The current–voltage (I–V) measurements of Sn/p-GaTe/In diode are carried out in the temperature range of 40–300 K with the steps of 10 K under dark conditions. While the ideality factor takes values between 1.03 and 1.24 at 300–180 K temperature range, it has values between 1.30 and 5.18 at 170–40 K temperature range. It is observed that the values of ideality factor and series resistance (RS) decrease with increasing temperature. The barrier height increases due to barrier inhomogeneity with increasing temperature since the current prefers to flow through the lowest barrier height with decreasing temperature. The temperature dependence of the inhomogeneous barrier height exhibites a double-Gaussian distribution. The mean barrier height and standard deviation values calculated from the barrier height versus 1/2 kT curve are 0.68 eV and 88.9 meV for the distribution-1 (D1) and 0.36 eV and 42.2 meV for the distribution-2 (D2), respectively. The Richardson constant (A*) value is calculated to be 41.7 for D1 and 55.0 A/K2cm2 for D2 from modified Richardson plot, respectively. These values are very close to the theoretical value of 55.8 A/K2cm2 for the p-GaTe semiconductor.