Impact of Na and/or Sb on the CTS thin films and solar cell performance

Cu2SnS3 (CTS) thin films were synthesized onto a soda lime glass substrate coated molybdenum by sulfurization the Cu–Sn stacks were prepared using RF sputtering. The influence of Na-doped CTS, Sb-doped CTS, and Sb+Na co-doped CTS films on their physical properties has been investigated. The undoped and doped films have been illustrated in a monoclinic structure with no shifts in peak position. Larger grain size has been obtained with Sb doping compared to undoped CTS. Enhancement in photoluminescence sharpening and yield spectra were indicated in the existence of Na and/or Sb. The power conversion efficiency was enhanced by the addition of Na and/or Sb to the CTS absorber layer, from 0.32% for undoped CTS to 1.54, 1.89 and 0.76% for Na, Sb, and co-doping CTS, respectively. As a result, the influence of doping has improved all cell efficiency with an increasing ratio of 381, 490, 137% with Na, Sb, and co-doping, respectively.