Temperature dependent electrical characteristics of Sn/p-Si Schottky diodes

Current–voltage and capacitance–voltage characteristics of Sn/p-Si Schottky diodes measured in the temperature range 80– 320 K are presented and analysed. Anomalous strong temperature dependencies of the ideality factor and apparent barrier height were obtained. There was also a considerable difference between the apparent barrier heights obtained from current–voltage and capacitance–voltage characteristics. These anomalies are explained by the domination of the current by a high level of thermionic-field emission, and by the presence of deep levels near the Sn/Si interface, which yield a reduction of free hole concentration and a significant temperature dependence of the charge stored near the metal–semiconductor (MS) interface. The evaluation of temperature dependence of forward current for thermionic-field emission resulted in the following parameters: characteristic energy E00 = 9.8 meV, Schottky barrier height at zero bias Fb0 = 0.802 eV, bias coefficient of barrier height b = 0, and effective Richardson constant A* = 37.32 A cm 2 K 2.