The temperature dependence of some electrical parameters of Au/n-GaAs/GaAs structures obtained from the forward bias current-voltage (I-V) and reverse bias capacitance-voltage (C-V) characteristics is studied in the temperature range of 79-400 K. The forward bias current I is found to be proportional to I-o(T)exp(An where A is the slope of Ln(I)-V curves and almost independent of the voltage and temperature, and I-o(T) is relatively a weak function of temperature. The semi-logarithmic Ln(l)-V characteristics based on the thermionic emission (TE) mechanism showed a decrease in the ideality factor (n) and an increase in the zero-bias barrier height (Phi(Bo)) with increasing temperature. These behaviors don't obey the pure thermionic emission (TE) theory. However, the barrier height OB(C-V) determined from the C-2-V plot at high frequency decreased linearly with the temperature. Analysis of the data indicated that the predominant current conduction mechanism of our sample was a trap-assisted multistep tunneling rather than the other mechanisms. (C) 2008 Elsevier Ltd. All rights reserved.