Fabrication and characterization of 150 nm tin antimony sulfide thin films, a promising window layer material for homojunction solar cells

A suitable combination of window and absorber layers plays a vital role in the fabrication of an efficient solar cell system. Here, we report the investigations concerning tin antimony sulfide, SnSb4S7 (TAS) thin film as an n-type window layer, prepared on the cleaned glass substrate via thermal evaporation technique. The obtained 150 nm thin films were annealed at 150, 200, 250, and 300 °C in an argon atmosphere, and then analyzed to get insight about its potential in a solar cell as an n-type window layer. The resistance of the films, determined via Van der Pauw technique, is found to be decreased (76–52 MΩ) with increasing annealing temperature. XRD analysis showed that the calculated crystallite size of the sample annealed at 300 °C was around 16 ± 0.5 nm, which is consistent with the characteristic range of window layer. Moreover, the calculated band gap (2.3–2.85 eV), low absorbance, and high transmittance values in the visible range also endorse the potential of TAS thin film for window layer.