The fabrication of Al/(PVA-ZnS)/p-Si (MPS) structures and investigating their electrical and dielectric properties in a wide range of frequency and temperature

In this study, Al/(ZnS-PVA)/p-Si (MPS) structures were prepared and main electrical and dielectric parameters of these structures were examined in detail in a wide temperature (140-340 K) and frequency (10 kHz-5 MHz) range. Capacitance-voltage (C-V) and conductivity-voltage (G/-V) measurements were used to calculate the main electrical and dielectric parameters. Experimental results confirmed that these parameters are strongly dependent on temperature, frequency and voltage. Both C and G/ increase with increasing temperature, but decrease with increasing frequency. The change in these parameters was mainly attributed to the density of the interface states (Nss) localized in the (ZnS-PVA)/p-Si interface and their lifetime (), polarization, interfacial polymer layer and structure resistance (Rs). However, it was seen that the Nss values and polarization are predominant in the interface layer accumulation region, especially with Rs being dominant in the depletion region. Measurements taken depending on the temperature showed that C/G-V values increased only with decreasing temperature of Rs. Voltage-dependent profiles of Nss and Rs were obtained using the Hill-Coleman and Nicollian-Brews methods, respectively, and both parameters decrease with increasing frequency and temperature. This decrease is due to the fact that interface conditions can easily follow the ac signal at low frequencies and there are not enough electric charges at low temperatures. The real and imaginary parts (ε', ε") of the complex dielectric constant, the real and imaginary parts (M', M") of electric modulus, the loss tangent (tanδ) and the electrical conductivity () values of the structure are similarly calculated using C and G / depending on both frequency and temperature. ε ', ε " and tanδ values increased with decreasing frequency and increasing temperature whereas M', M" and ac decreased with increasing on both frequency and temperature. This situation was attributed to the restructuring-reordering of the interface states under the effects of externally applied dc voltage, frequency and temperature. The resulting dielectric constant of greater than 1 at 10 kHz indicates that the (ZnS-PVA) polymer interface layer grown at Al interface with p-Si interface can successfully replace the classical insulating SiO2 layer.