Gaussian distribution of inhomogeneous barrier height in Au/n-Si (111) Schottky barrier diodes at low temperatures

Forward bias current–voltage (I–V) characteristics of Au/n-Si (111) Schottky barrier diode (SBD) were investigated in the temperature range of 80–290 K. Analysis of temperature dependent I–V data in terms of thermionic emission (TE) theory revealed an abnormal increase in zero-bias barrier height (ΦBo) and decrease in ideality factor (n) with increasing temperature. Such behavior of ΦBo and n was attributed to barrier inhomogeneities by assuming a Gaussian distribution (GD) of barrier height. Therefore, mean barrier height and effective Richardson constant (A⁎) values were extracted from the modified Richardson plot, and extracted A⁎ was found close to the theoretical value for n-type Si. Hence, it has been concluded that temperature dependent I–V characteristics of the SBD can be successfully explained on the basis of TE theory with GD of barrier height. In addition, series resistance and energy profile of density of interface traps in the SBD were also investigated.