On the temperature dependence of series resistance and interface states in Al/SiO2/p-Si (MIS) Schottky diodes

The capacitance–voltage–temperature (C–V–T) and conductance–voltage–temperature (G/w–V–T) characteristics of metal–semiconductor (Al/p-Si) Schottky diodes with thermal growth interfacial layer were investigated by considering series resistance effect in the wide temperature range (80–400 K). It is found that in the presence of series resistance, the forward bias C–V plots exhibit a peak, and experimentally shows that the peak positions shift towards higher positive voltages with increasing temperature, and the peak value of the capacitance has a maximum at 80 K. The C–V and (G/w–V) characteristics confirm that the Nss and Rs of the diode are important parameters that strongly influence the electric parameters in (Al/SiO2/p-Si) MIS Schottky diodes. The crossing of the G/w–V curves appears as an abnormality when seen with respect to the conventional behaviour of the ideal MS or MIS Schottky diode. It is thought that the presence of a series resistance keeps this intersection hidden and unobservable in homogeneous Schottky diodes, but it appears in the case of inhomogeneous Schottky diode. In addition, the high frequency (Cm) and conductance (Gm/w) values measured under both reverse and forward bias were corrected for the effect of series resistance to obtain the real diode capacitance.