The forward and reverse bias capacitance-voltage (C V) and conductance-voltage (G/w-V) characteristics of Al-TiW-Pd2Si/n-Si structures have been investigated over a wide frequency range of 5 kHz-5 MHz. These measurements allow to us the determination of the interface states density (N-ss) and series resistance (R-s) distribution profile. The effect of R-s on C and G is found noticeable at high frequencies. The C-V-f and G/w-V-f characteristics of studied structures show fairly large frequency dispersion especially at low frequencies due to N-ss in equilibrium with the semiconductor. The N-ss profile was obtained both forward bias current-voltage (I-V) characteristics by using into account the bias dependent of the ideality factor and effective barrier height (Phi(e)) and low frequency (C-LF)-high frequency method. The plot of series resistance vs. voltage for the low frequencies gives a peak, decreasing with increasing frequencies. The frequency dependent C-V and G/w-V characteristics confirm that the R, and N-ss of the Al-TiW-Pd2Si/n-Si structures are important parameters that strongly influence the electric parameters in device. (c) 2007 Elsevier B.V. All rights reserved.