Electrical and dielectric properties of Al/HfO2/p-Si MOS device at high temperatures

• C–V and G/w–V characteristics were investigated in the high temperatures.
• The capacitance decreases with rise in temperature.
• The capacitance decreases with increasing frequency.
• The values of ɛ′ and ɛ″ was calculated as a function of temperature and frequency.
• tan δ increases with rise in temperature, as decreases with increasing frequency.

The temperature dependence of capacitance–voltage (C–V) and conductance–voltage (G/w–V) characteristics of Al/HfO2/p-Si metal-oxide-semiconductor (MOS) device has been investigated by considering the effect of series resistance (Rs) and interface state density (Nss) over the temperature range of 300–400 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 MOS device. It is found that in the presence of series resistance, the forward bias C–V plots exhibits a peak, and its position shifts towards lower voltages with increasing temperature. The density of Nss, depending on the temperature, was determined from the (C–V) and (G/w–V) data using the Hill–Coleman Method. Also, the temperature dependence of dielectric properties at different fixed frequencies over the temperature range of 300–400 K was investigated. In addition, the electric modulus formalisms were employed to understand the relaxation mechanism of the Al/HfO2/p-Si structure.