An investigation on SnS layers for solar cells fabrication with CdS, SnS₂ and ZnO window layers prepared by nebulizer spray method

The preparation of SnS, CdS, SnS₂ and ZnO thin films by nebulizer spray method, and their characterization is reported. The size of crystallites, dislocation density, texture coefficient and strain were estimated using XRD data. SEM study revealed good surface morphology of films. Optical properties of deposited SnS, CdS, SnS₂ and ZnO films were estimated using the optical absorption measurements. The calculated optical energy gaps of CdS, SnS₂, ZnO and SnS films were, respectively, found as 2.45, 2.41, 3.2 and 1.45 eV. Hall effect measurements exhibited p-type conductivity for SnS and n-type conductivity for CdS, SnS₂, ZnO thin films. The grown SnS thin films showed resistivity and carrier concentration as 0.0689 Ωcm and 1.04 × 10¹⁹ cm^{− 3}, respectively. Heterojunction solar cells of FTO/CdS/SnS, FTO/SnS₂/SnS, and FTO/ZnO/SnS were also fabricated and their properties studied. The fabricated FTO/ZnO/SnS heterojunction solar cell presented a superior performance with conversion efficiency (0.96%) greater than other structures.