Efficiency enhancement of Sb₂Se₃ thin-film solar cells by the co-evaporation of Se and Sb₂Se₃

Abstract

Abstract In this work, we present an alternative route to supply excessive selenium (Se) for the deposition of Sb 2 Se 3 thin films by the co-evaporation of Se and Sb 2 Se 3 . Scanning electron microscopy (SEM) images showed that additional Se modified the growth process and surface morphology of Sb 2 Se 3 thin films. X-ray diffraction (XRD) patterns confirmed that this co-evaporation process enhanced the beneficiary preferred orientations, and capacitance–voltage ( C – V ) measurement showed that the carrier concentration of the Sb 2 Se 3 absorber increased with the additional evaporation of Se. Accordingly, the efficiency of the devices employing co-evaporated Sb 2 Se 3 absorber layers increased significantly from 2.1 to 3.47% with a open-circuit voltage ( V OC ) of 364 mV, a short-circuit current density ( J SC ) of 23.14 mA/cm 2 , and a fill factor (FF) of 41.26%.