Optical properties change in amorphous (As2S3)0.87Sb0.13 thin films by photo and thermal induced process

▶ The article describes the optical properties change due to light illumination and thermal annealing on (As2S3)0.87Sb0.13 thin film. ▶ The reduction of optical bandgap (photodarkening) due to light illumination is due to the creation of homopolar bonds whereas increase in optical bandgap (photobleaching) due to annealing is due to the increase in heteropolar bonds. ▶ New bonds are formed due to the chemical bond redistribution which can be observed from the XPS core level spectra and raman shift.