Two-diode behavior in metal-ferroelectric-semiconductor structures with bismuth titanate interfacial layer

Abstract

In this study, electrical parameters of the Al/Bi4Ti3O[Formula: see text]/p-Si metal-ferroelectric-semiconductor (MFS) structure and their temperature dependence were investigated using current–voltage (I–V) data measured between 120 K and 300 K. Semi-logarithmic I–V plots of the structure revealed that fabricated structure presents two-diode behavior that leads to two sets of ideality factor, reverse saturation current and zero-bias barrier height (BH) values. Obtained results of these parameters suggest that current conduction mechanism (CCM) deviates strongly from thermionic emission theory particularly at low temperatures. High values of interface states and nkT/q[Formula: see text]−[Formula: see text]kT/q plot supported the idea of deviation from thermionic emission. In addition, [Formula: see text](I)[Formula: see text]−[Formula: see text][Formula: see text](V) plots suggested that CCM varies from one bias region to another and depends on temperature as well. Series resistance values were calculated using Ohm’s law and Cheungs’ functions, and they decreased drastically with increasing temperature.