© 2019, Springer Science+Business Media, LLC, part of Springer Nature.Au/n-Si (MS) and Au/(SnO2-PVA)/n-Si (MPS) type SDs were manufactured at identical conditions for investigation of the (SnO2-PVA) organic/polymer interlayer effects on the electrical characteristics using voltage dependent current (I) and capacitance/conductance (C/G) data and compared each other. Rectifying ratio (RR) and the barrier height (BH) were found from forward bias ln(I)–V plots,. The values found are 2.5 × 102 and 0.57 eV for MS type SDs and 2 × 103 and 0.68 eV for MPS type SDs, respectively. The ideality factor (n), series resistance (Rs) and BH were also calculated from Cheung’s functions. They are agreement observed to be compatible with other results. The surface states versus (Ec−Ess) and Rs versus V curves were calculated by using the I–V data by using Roderick and Ohm’s law. The doping donor atoms (ND), Fermi energy (EF), BH of these SDs were also calculated from the reverse bias C−2–V data. While the calculated values of surface states and leakage current for the MPS is lower than Au/n-Si SD, RR is higher. Obtained results prove the use of a (SnO2-PVA) organic interlayer improved the performance of the Au/n-Si diodes.