Dielectric investigation of In4Se96-xSx semiconductor: Relaxation and conduction mechanism

Dielectric properties of amorphous semiconductor has been observed in the frequency range of 1 kHz - 1 MHz and a temperature range of 300 K-370 K. Dielectric dispersion is observed in the present samples which is dipolar in nature. The decrease in the dielectric parameter with Sulfur concentration may be due to the decrease in density of defect states. DC conduction loss is smaller than the observed dielectric loss. The analysis of the experimental results indicates that the ac conductivity is temperature, frequency and concentration dependent. Ac conductivity is found to obey the power law omega(s), where s (<) 1. A strong dependence of ac conductivity and exponent s can be well interpreted in terms of correlated barrier hopping (CBH) model. The maximum barrier height W-m were calculated from the results of dielectric loss according to Guintini equation that agree with the theory of hopping of charge carriers over potential barrier as suggested by Elliot in case of chalcogenide semiconductors. The effect of Sulfur was investigated for the obtained results of the studied parameters.