Determining electrical and dielectric parameters of Al/ZnS-PVA/p-Si (MPS) structures in wide range of temperature and voltage

Abstract

In this study zinc sulphide (ZnS) nanostructures have been prepared by microwave-assisted method in presence of polyvinyl alcohol (PVA) as a capping agent. The structural and morphological properties of prepared sample have been investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). These analyses confirm that the sample has nano structure. They have been used this sample to fabrication of Al/ZnS-PVA/p-Si structure. The effect of temperature and voltage on the electrical and dielectric parameters of the Al/ZnS-PVA/p-Si (MPS) structures has been investigated in the wide range of temperature (140–340 K) and voltage (− 2 V to + 4 V) using capacitance/conductance-voltage (C/G–V) measurements at 500 kHz. Experimental measurements revealed that the values of C/G–V increase with increasing temperature but the values of series resistance (Rs) increase with decreasing temperature. As well as the dielectric parameters such as the values of real and imaginary parts of the dielectric constants (e′ and e″) and electric modules (M′ and M″), loss tangent (tanδ), and ac electrical conductivity (σac) were obtained using C and G/ω data. These parameters are found out as strong functions of temperature and voltage. While the values of e′, e″ and tanδ increase with increasing temperature, the values of σac, M′ and M″ decrease. The Arrhenius plot (ln(σac) vs q/kT) shows two distinct linear ranges with different slopes or activation energies (Ea) at low (140–230 K) and high (260–340 K) temperatures. Both values of Rs and (ZnS-PVA) interfacial layers are also very effective parameters on the electric and dielectric properties.