The analysis of the series resistance and interface states of MIS Schottky diodes at high temperatures using I–V characteristics

The temperature dependence of the current–voltage (I–V) characteristics of Au/SiO2/n-Si (MIS) Schottky diodes has been measured in the temperature range of 300–400 K. Based on the thermionic emission (TE) theory, the forward and reverse I–V characteristics are analyzed to calculate the MIS Schottky diode barrier parameters. The calculated zero-bias barrier height (ΦBo) and ideality factor (n) assuming TE theory show strong temperature dependence. A decrease in the value of n and an increase in ΦBo with increasing temperature is observed. The calculated values of ΦBo and n varied from 0.63 eV and 2.90 at 300 K to 0.80 eV and 1.79 at 400 K, respectively. Also, the temperature dependence of energy distribution of interface states (Nss) was obtained from the forward bias I–V measurements by taking into account the bias dependence effective barrier height (Φe) and ideality factor (n). In addition, the values of series resistance (Rs) were determined using Cheung's method. These I–V characteristics confirmed that the distributions of Nss and Rs are important parameters that influence the electrical characteristics of MIS Schottky diodes.