Optical and electrical properties of In4Se96-xSx chalcogenide thin films

Abstract

The objective is to study the physical, structural, compositional, electrical and optical changes in InSeS alloy. In4Se96-xSx (where x = 0, 4, 8, 12) chalcogenide semiconductors has been deposited on non-conducting glass substrate by thermal evaporation technique at a pressure of approximately 10−6 Torr. The thin films were characterized by XRD, SEM, UV spectroscopy and electrical measurement. XRD shows the amorphous nature of the prepared thins films. Surface morphological analysis were carried out by scanning electron microscope (SEM), which shows the grain development of the prepared samples. Energy dispersive analysis by X-ray (EDAX) was used to check the compositional elements of deposited films. The analysis of the absorption spectra show indirect band gap, the magnitude of optical band gap increases and the corresponding absorption coefficient decreases with Sulfur concentration. The temperature dependent DC Conductivity (σdc) decreases and the corresponding activation energy increases with increase of Sulfur content for the In4Se96-xSx. High field conduction study shows the space charge limited conduction (SCLC) is dominated from where the density of states has been evaluated, density of state decreases with increases of sulfur concentration which may be due to decrease in disorderness or decrease in defects states of the system.