Evaporated and solution deposited planar Sb₂S₃ solar cells: A comparison and its significance

Sb 2 S 3 is an alternative emerging material for chalcogenide solar cells. In this paper, we compare planar solar cells in which the Sb 2 S 3 absorber was deposited by either thermal evaporation or a solution based process. The planar inorganic solar cell with evaporated Sb 2 S 3 has an efficiency of 1.7%. This is much higher than the efficiency of 0.8% for solution deposited Sb 2 S 3 , and the highest known reported efficiency for a planar Sb 2 S 3 solar cell with a CuSCN hole conducting layer. The evaporated Sb 2 S 3 film is sulfur‐rich, which results in flattening of the film surface after annealing at 300 °C, thereby reducing the likelihood of contact between the Sb 2 S 3 and gold contact. In addition, the crystal size of the evaporated Sb 2 S 3 film is about 30% larger than that of the solution deposited Sb 2 S 3 and has different preferential crystal planes. These features make evaporation a promising deposition method for flat solar cells made from sulfur‐based semiconducting materials. Cross section image of the evaporated Sb 2 S 3 solar cell with labels for each layer.