Photovoltaic behavior of the room temperature grown RF-Sputtered SnS thin films

Tin sulfide (SnS) thin films were deposited on the soda lime glass (SLG) and Mo-coated SLG by radio frequency sputtering method at room temperature (RT). The structural, optical, and the photovoltaic properties were investigated by varying the argon pressure (P-Ar) from 6 to 50 mTorr. The scanning electron microscopy (SEM), electron dispersive spectroscopy (EDX), X-ray diffraction (XRD), micro-Raman spectroscopy, and photoluminescence spectroscopy (PL) confirmed that the as-grown samples at 30 mTorr pressure showed the single phase of orthorhombic SnS with the stoichiometric ratio. The variation in the grain size, shape, and a shift in the crystal plane from (111) to (101) were ascertained with an increase of P-Ar. The ultraviolet-visible spectroscopy revealed that all the SnS films exhibited a constant high optical absorption coefficient of 5.8 x 10(4) cm(-1), whereas, the energy band gap reduced from 1.50 to 1.35 eV with the increase of P-Ar. The solar cell of RT-SnS at 30 mTorr showed the best power conversion efficiency of 0.38%.