AN ASSESSMENT ON ELECTRICAL CHARACTERIZATION OF Ni/n-Si SCHOTTKY RECTIFIERS WITH AND WITHOUT Ta2O5 INTERFACIAL OXIDE LAYER

Abstract

We have fabricated Ni/[Formula: see text]-Si metal–semiconductor (MS) and Ni/Ta2O5/[Formula: see text]-Si metal-insulator–semiconductor (MIS) Schottky barrier diodes at room temperature and studied their current density–voltage (J–V) and capacitance–voltage (C–V) characteristic properties. The forward bias J–V characteristics of the fabricated MS and MIS devices have been evaluated with the help of the thermionic emission (TE) mechanism. Schottky barrier height (SBH) values of 0.73 and 0.84[Formula: see text]eV and ideality factor values of 1.75 and 1.46 are extracted using J–V measurements for MS and MIS Schottky barrier diodes without and with Ta2O5 interfacial oxide layer, respectively. It was noted that the incorporation of Ta2O5 interfacial oxide layer enhanced the value of SBH for the MIS device because this oxide layer produced the substantial barrier between Ni and [Formula: see text]-Si and this obtained barrier height value is better than the conventional metal/[Formula: see text]-Si (MS) Schottky diodes. The rectification ratio (RR) calculated at [Formula: see text][Formula: see text]V for the MS structure is found to be [Formula: see text] and the MIS structure is found to be [Formula: see text]. Using Chung’s method, the series resistance ([Formula: see text]) values are calculated using [Formula: see text]/[Formula: see text] vs I plot and are found to be 21,603[Formula: see text][Formula: see text] for the Ni/[Formula: see text]-Si (MS) and 5489[Formula: see text][Formula: see text] for the Ni/Ta2O5/[Formula: see text]-Si (MIS) structures, respectively. In addition, [Formula: see text] vs [Formula: see text] plot has been utilized to evaluate the series resistance ([Formula: see text]) values and are found to be 14,064[Formula: see text][Formula: see text] for the Ni/[Formula: see text]-Si (MS) and 2236[Formula: see text][Formula: see text] for the Ni/Ta2O5/[Formula: see text]-Si (MIS) structures, respectively. In conclusion, by analyzing the experimental results, it is confirmed that the good quality performance is observed in Ni/Ta2O5/[Formula: see text]-Si (MIS) type SBD when compared to Ni/[Formula: see text]-Si (MS) type SBD and can be accredited to the intentionally formed thin Ta2O5 interfacial oxide layer between Nickel and [Formula: see text]-type Si.