Photo sensing properties of zirconium doped Sn2S3 thin films grown by cost effective nebulizer spray pyrolysis technique

Polycrystalline pure tin trisulfide (Sn₂S₃) thin films and Zr doped tin trisulfide thin films (doped with 2, 4, 6, 8, and 10 wt% Zr) were fabricated using a cost-effective Nebulizer Spray Pyrolysis (NSP) method with improved opto electronic characteristics. These films were designed for integration into light-sensing devices due to their uniformity as a result of controlled doping. The orthorhombic crystal structure was observed in all samples and X-ray diffraction analysis revealed that all fabricated films were of polycrystalline nature. The crystallite size was found to increase up to 8 wt% doping of Zr. Field emission scanning electron microscopy images indicate that the surface contains uniform spherical grains with their size varying with Zr doping concentration. The band gap of the material increased with the introduction of more Zr into Sn₂S₃, but initially the optical band gap values decreased up to 8 %. Photo-sensing tests revealed that the sensing characteristics of Zr doped Sn₂S₃ thin films enhanced up to 8 % Zr doping after which they began to decline. The R, EQE and D* values were found to be 51.6 × 10⁻²AW^-1, 121 % and 24.8 × 10⁹ Jones respectively, indicating the highest levels of responsiveness, external quantum efficiency and detectivity attained for 8 % Zr doping. The improved photodetection capability may be due to the reduced charge carrier recombination rates and appropriate crystallite size. The sample of Sn₂S₃ thin film that has 8 wt% of Zr doping shows the maximum photocurrent. The present study suggests that doping Sn₂S₃ thin films with 8 wt% Zr effectively enhances their properties, making them more suitable for optoelectronic applications.