Optoelectronic properties of the InSe/Ga2S3 interfaces

Abstract

Abstract In this work, the nature of formation, the structural, optical and optoelectronic properties of the InSe/Ga2S3 interfaces are explored by the Scanning electron microscopy, energy dispersive X-ray, X-ray diffraction, optical spectrophotometry and temperature dependent dark and photoconductivity. The InSe/Ga2S3 interfaces that are prepared by the vapor deposition technique are observed to exhibit a physical nature of stacking with correct atomic stoichiometry of the layers. The deposition of the Ga2S3 onto InSe substrate is induced to exhibit a polycrystalline nature. In addition, the optical characterizations have shown that the presence of Ga2S3 onto the top surface of InSe enhances the absorbability significantly and causes valence and conduction band offsets of 0.35 and 1.25 eV, respectively. On the other hand, the temperature dependent photoconductivity analysis in the range of 330–160 K, have shown that the conduction is dominated by the thermionic and variable range hopping transport mechanisms. The photoexcitation process tunes the current transport mechanisms. When the InSe/Ga2S3 interface devices were exposed to laser light irradiations of wavelengths of 406 and 850 nm, promising photocurrent characteristics were observed. Namely, the linear growth of the photocurrent, responsivity, external and internal quantum efficiencies with increasing biasing voltage under these two laser lights nominates the InSe/Ga2S3 interfaces for optoelectronic applications.