Electrical and photovoltaic properties of Au/(Ni, Zn)-doped PVA/n-Si structures in dark and under 250Â W illumination level

Electrical and photovoltaic properties of Au/(Ni, Zn)-doped PVA/n-Si structures were investigated in dark and under 250 W illumination level using forward and reverse bias current-voltage (I-V) measurements at room temperature. Reverse saturation current (Io), ideality factor (n), and zero-bias-barrier height (ΦBo) values were found as 1.18×10−8 A, 2.492 and 0.705 eV in dark (low region); 9.10×10−7 A, 7.515 and 0.597 eV in dark (high region); and 1.05×10−6 A, 6.053 and 0.593 eV under 250 W illumination level. The forward bias semi-logarithmic I-V plot in dark was described using a two-diode model, indicating two current-transport mechanisms acting in the diode. The first mechanism can be attributed to recombination of carriers between Au/(Ni, Zn) and doped PVA, and second one can be attributed to recombination in the depletion region. In addition, the energy density distribution profile of surface states (Nss) was extracted from the forward-bias I-V data by taking into account the voltage dependent of the effective barrier height (Φe), ideality factor n(V), and series resistance (Rs).