Fabrication of Cost-Effective Nebulizer Sprayed In2S3 Thin Films for Photodetector Applications

The present study investigates the effect of precursor solution volume on the structural, morphological, compositional, optical, and electrical properties of In2S3 films. Thin films of In2S3 were deposited by a nebulizer spray pyrolysis technique on glass substrates with varying precursor solution volumes (4 mL, 8 mL, 12 mL, and 16 mL). X-ray diffraction studies confirmed the formation of the tetragonal phase and the compositional studies using energy-dispersive x-ray spectra showed the presence of only indium and sulfur. The energy bandgap of the films was found to be in the range of 2.51–2.4 eV. The I-V characteristics and photoresponses of the photodetectors including photosensitivity, responsivity, and detectivity were evaluated under visible light illumination. Enhanced photo-responsivity was observed with an increase in the precursor solution volume, with a maximum value of 0.213 AW−1 observed for the thin film coated with 12 mL precursor solution volume. For the thin film coated with a volume of 12 mL precursor solution, external quantum efficiency of 69% and detectivity of 20 × 109 Jones were observed. This In2S3 thin film may find application in the fabrication of efficient and cost-effective photodetector devices.