A study on Au/n-Si Schottky barrier diodes (SBDs) parameters with and
without thin native oxide layer fabricated on n-type Si grown by LPE (Liquid-Phase
Epitaxy) technique has been made. The native oxide layer with different thicknesses on
chemically cleaned Si surface was obtained by exposing the Si surfaces to clean room
air before metal evaporation. The native oxide thicknesses of samples D2, D3, D4 and
D5 are in the form D2 < D3 < D4 ≤ D5 depending on the exposing time. It has been seen
that the value of the barrier height Φb 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 to
that of the initial sample D1 (the initial sample, 0.74 eV), and thus also their
I − V
curves. Especially, the experimental results related to the exposure time of the
surfaces to clean air are close in agreement with recently results reported for the
HF-treated n-Si surface during initial oxidation in air. Furthermore, it has been
determined experimentally that ageing of the Au contacts on the oxidized epilayer Si
leads to barrier height values close to those measured for Au on chemically cleaned
surfaces.