Analysis of I–V–T Characteristics of Au/n-InP Schottky barrier diodes with modeling of nanometer-sized patches at low temperature

The aim of the work is to investigate the current-voltage (I-V) characteristics of inhomogeneous Au/n-InP Schottky barrier (SB) diodes in the 100-300 K temperature range. More in detail, a numerical simulation study is carried out by using a physical device simulator and the diode I-V experimental curves are fitted both in forward and reverse bias conditions by explaining the current transport mechanisms at low temperature. Tunneling current flows through the native oxide and nanometer-sized patches embedded at the Au/n-InP interface. These patches determine a lower barrier height (local) which is temperature-dependent and responsible of the diode current behaviors in the low bias regime. The patch area is in the order of one-millionth of the total diode area and the SB is between 0.01 and 0.3 eV in the patch region. The simulations are in good agreement with the measurements in the whole explored current range extending over six orders of magnitude.