The novel design of gold/polypyrrole-multi-walled carbon nanotubes/titanium dioxide/aluminum oxide/P-type silicon/aluminum (Au/PPy-MWCNTs/TiO2/Al2O3/p-Si/Al) is utilized to fabricate supercapacitors, sensors, diodes, and microelectronic devices. The electrical characteristics of the structure are examined both in the dark and under illumination to evaluate its photosensing performance. The real part of the AC conductivity at all voltages and temperatures is observed to be low at low- and mid-frequencies but significantly increases at high frequencies. The imaginary part of the AC conductivity exhibits three distinct behaviors: it is positive at low frequencies and shows both negative and positive values at high frequencies. At specific temperatures, such as 293, 273, and 253 K, the imaginary component of the AC conductivity (σ ac) is negative only at high frequencies. In the Cole-Cole diagrams, the symmetrical semicircles increase with temperature for all voltages, except at V = -2 V. The real part of the electric modulus (M′) shows positive and negative values; however, at certain temperatures, it is positive. The imaginary part of the modulus (M″) is consistently positive.

The current work presents a new structure based on Au/PVA/SiO2/p-Si/Al that has not been studied before. An aqueous solution of polyvinyl alcohol (PVA) polymer gel was deposited on the surface of SiO2/Si using the spin-coating technique. The silicon wafer was left to be oxidized in a furnace at 1170 k for thirty minutes, creating an interdiffusion layer of SiO2. The variations in the dielectric constant (Є′), dielectric loss (Є″), and dielectric tangent (tanδ) with the change in the frequency, voltage, and temperature were analyzed. The results showed an increase in the dielectric constant (Є′) and a decrease in the dielectric loss (Є″) and tangent (tanδ); thus, the Au/PVA/SiO2/p-Si/Al heterostructure has opened up new frontiers for the semiconductor industry, especially for capacitor manufacturing. The Cole–Cole diagrams of the Є″ and Є′ have been investigated at different temperatures and voltages. The ideality factor (n), barrier height (Φb), series resistance (Rs), shunt resistance (Rsh), and rectification ratio (RR) were also measured at different temperatures.