The investigation of effects of (Fe₂O₄-PVP) organic-layer, surface states, and series resistance on the electrical characteristics and the sources of them

In this work, Au/n-Si (MS) structures with and without (Fe₂O₄-doped PVP) interlayer were prepared with the same conditions to see effects of organic layer on the electrical characteristics and conduction mechanisms. For this aim, I–V and Z–V measurements of them were carried out at room temperature. The saturation current (I_s), ideality factor (n), barrier height (Φ_B(I–V)), series (R_s) and shunt (R_sh) resistances, and rectifying rate (RR = I_F/I_R) of them were extracted from the I–V data as 2.90 × 10⁻⁸ A, 1.699, 0.741 eV, 1.58 kΩ, 25.7 MΩ, 1.45 × 10⁴ for MS and 2.30 × 10⁻⁹ A, 1.634, 0.806 eV, 1.17 kΩ, 103 MΩ, 9.01 × 10⁴ for MPS, respectively. The values of interface states (N_ss) were also extracted from the I–V data at forward bias by considering voltage dependent BH and n, and it is found that they increase from the mid-gap of semiconductor towards the conductance band. The values of doping atoms (N_D), Fermi-energy (E_F), and (Φ_B(C–V)) were also acquired from the C⁻²–V plots at reverse bias as 9.08 × 10¹⁴ cm⁻³, 0.258 eV, 0.914 eV for MS and 7.650 × 10¹⁴ cm⁻³, 0.263 eV, 0.981 eV, for MPS structure, respectively. It is clear that the (Fe₂O₄-PVP) interlayer leads to decreases in R_s, N_ss, leakage current and increase in rectifying rate (RR), R_sh and BH, so that it can used in place of the conventional oxide or insulator layer.