Chemically synthesized Cu-doped SnS thin films for PV applications.

Abstract

As the concern towards the sustainable and eco-friendly development increased in the recent times, research is being done on lesser toxic and abundant materials that can be used for Photovoltaic (PV) applications. SnS seems to be a promising solution in this direction. The suitability of pure and doped SnS thin films as absorber layer in a solar cell is experimented and verified widely in the recent past. In this paper, the suitability of Copper (Cu)-doped SnS thin films deposited through Chemical Bath Deposition (CBD) is verified for which the structural, optical, electrical properties in addition to the composition of the synthesized thin films are studied. An increasing trend was observed in the crystallinity with the Cu-doping concentration up to 5 at%. The range of optical band gap variation was observed between 1.193 eV to 1.25 eV. The electrical resistivity decreased while the charge carrier concentration increased. The lowest value of 2.12x10^-2 ohm-cm for electrical resistivity and the highest value of 4.68x10¹⁹ cm^-3 for carrier concentration were recorded by 5 atomic % Cu-doped SnS thin films.