Ti/n-GaAs Schottky barrier diodes (SBDs) have been fabricated on LEC grown silicon-doped (1 0 0)GaAs single crystals. The SBDs have been irradiated using low-energy proton ions of fluences 5 x 10(13), 1 x 10(14) and 1 x 10(15) pcm(-2) to study the effect of irradiation damages close to the interface. The diode parameters ideality factor (n), barrier height (phi(B)) and series resistance (R-s) were evaluated from forward I-V characteristics using an innovative approach. The diodes were annealed with different temperatures. Better enhancement in the barrier height and an improvement in the ideality factor has been observed at the annealing temperature of 623 K. This is due to the removal of irradiation induced defects at the interface upon annealing. The major advantages of this method are the diode parameters with high series resistance can be evaluated and the linear regression can be used for the entire bias range, which raise the accuracy of the results. In this article, the best fitted Schottky barrier diode parameters and the experimental results are compared and discussed.