Deposition and Characterization of Indium Selenide Thin Films for Opto-electronic Devices

Abstract

Amongst all the III-VI semiconductors, ones that crystallize with a layered structure have gained special interest due to its significant usage in photovoltaic devices. III-VI layered semiconductor such as InSe has low density of dangling bonds on its surface therefore it is considered as vital material for the fabrication of opto-electronic devices like photo sensor, solar cell etc. In present work, InSe thin films were fabricated through a simple and facile drop-casting method, where the thin films were drop-casted between two silver paste electrodes on a glass substrate. The structural, surface morphological, compositional, electrical and optical properties of the prepared films were obsrved by XRD, SEM, EDAX, high precision digital multi-meter and UV-visible spectroscopy, respectively. XRD analysis of the prepared film shows the existence of nano-crystalline nature with monoclinic crystal structure of InSe. SEM images show good continuity of InSe film. InSe thin films are n-type with bandgap of 1.8 eV and their electrical conductivity is in the order of 10 – 10 S/cm that makes them appropriate for using as an absorber layer in the solar cell.