Graphene doped (Bi2Te3–Bi2O3–TeO2): PVP dielectrics in metal–semiconductor structures

To determine the influence of the thin polymer interface film on the electrical and dielectric characteristics of the Al/p-Si MS structure, the Graphene doped (Bi2Te3–Bi2O3–TeO2): PVP film was deposited on the silicon substrate using the spin-coating method. The mean size of these nanostructures was found less than 50 nm using the XRD method. EDX profile shows that the structure of Bi2Te3–Bi2O3–TeO2 consists of the bismuth (Bi), tellurium (Te), and oxygen (O) atoms and also not consists of other impurities or compounds. The key electrical and dielectric parameters of metal–semiconductor (MS) and metal-polymer/semiconductor nanocomposite structures were examined using I–V and Z–f analyses. The values of saturation-current (I0), barrier-height (BH) at zero-bias (ΦB0), ideality factor (n), series and shunt resistances (Rs, Rsh) data for both structures were derived from the I–V experiments at ± 6 V voltage scales and compared with them. The energy distributions of interface state density (Dit) were also acquired from the voltage-dependent ΦB(V) and n(V) data. Finally, the frequency dependence of complex dielectric (ε* = ε′ − jε″) and electric modulus (M* = M′ + jM″), dielectric loss tangent (tanδ), and ac electrical conductivity (σac) values were evaluated from the C–f and G/ω–f experiments for both structures at 102–106 Hz frequency scale. The results depict that the Bi2Te3–Gr: PVP organic layer improves the quality of the MS structure as it reduces the leakage current, n, and Dit and increases the Rsh, BH, and ε′.