The current-voltage (I-V) characteristics of Al/SnO2/p-Si (MIS) Schottky diodes prepared by means of spray deposition method have been measured at 80, 295 and 350 K. In order to interpret the experimentally observed non-ideal Al/SnO2/p-Si Schottky diode parameters such as, the series resistance R-s, barrier height Phi(B) and ideality factor n, a novel calculation method has been reported by taking into account the applied voltage drop across inter-facial oxide layer V-i and ideality factor n in the current transport mechanism. The values obtained for V-i were subtracted from the applied voltage values V and then the values of R-s were recalculated. The parameters obtained by accounting for the voltage drop V-i have been compared with those obtained without considering the above voltage drop. It is shown that the values of R-s estimated from Cheung's method were strongly temperature-dependent and decreased with increasing temperature. It is shown that the voltage drop across the interfacial layer will increase the ideality factor and the voltage dependence of the I-V characteristics. The interface state density N-ss of the diodes has an exponential growth with bias towards the top of the valance band for each temperature; for example, from 2.37 x 10(13) eV(-1) cm(-2) in 0.70-E-v eV to 7.47 x 10(13) eV(-1) cm(-2) in 0.62-E-v eV for 295 K. The mean N-ss estimated from the I-V measurements decreased with increasing the temperature from 8.29 x 10(13) to 2.20 x 10(13) eV(-1) cm(-2). (C) 2004 Elsevier B.V. All rights reserved.