A study on Au/n-Si Schottky barrier diodes (SBDs) parameters with andwithout thin native oxide layer fabricated on n-type Si grown by LPE (Liquid-PhaseEpitaxy) technique has been made. The native oxide layer with different thicknesses onchemically cleaned Si surface was obtained by exposing the Si surfaces to clean roomair before metal evaporation. The native oxide thicknesses of samples D2, D3, D4 andD5 are in the form D2 < D3 < D4 ≤ D5 depending on the exposing time. It has been seenthat the value of the barrier height Φ b of samples D2 (0.64 eV), D3 (0.66 eV), D4(0.69 eV) and D5 (0.69 eV) increases with increasing the exposure time and tends tothat of the initial sample D1 (the initial sample, 0.74 eV), and thus also their I − Vcurves. Especially, the experimental results related to the exposure time of thesurfaces to clean air are close in agreement with recently results reported for theHF-treated n-Si surface during initial oxidation in air. Furthermore, it has beendetermined experimentally that ageing of the Au contacts on the oxidized epilayer Sileads to barrier height values close to those measured for Au on chemically cleanedsurfaces.