The frequency and voltage dependent electrical characteristics of Al–TiW–Pd 2Si/n-Si structure using I– V, C– V and G/ ω– V measurements

Abstract

The forward and reverse bias capacitance–voltage ( C–V) and conductance–voltage ( G/ w–V) characteristics of Al–TiW–Pd 2Si/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 ( Φ e) and low frequency ( C LF)–high frequency ( C HF) 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 s and N ss of the Al–TiW–Pd 2Si/n-Si structures are important parameters that strongly influence the electric parameters in device.