An Au/Aniline blue (AB)/p-Si/Al structure has been fabricated and then the effect of electron irradiation (12 MeV electron energy and 5 x 10(12) e(-) cm(-2) fluence) on the contact parameters of the device has been analysed by using the current-voltage (I-V), capacitance-voltage (C-V), and conductance-voltage (G/w-V) measurements, at room temperature. Since the organic layer creates a physical barrier between the metal and the semiconductor, it has been seen that the AB layer causes an increase in the effective barrier height of the device. Cheung functions, Norde model and conductance method have been used in order to determine the diode parameters. The values of the ideality factor, barrier height and series resistance increased after the electron irradiation. This has been attributed to a decrease in the net ionized dopant concentration that occurred as a result of electron irradiation. (C) 2011 Elsevier Ltd. All rights reserved.