Bulk Defect Passivation for Full‐Inorganic Sb₂S₃ Solar Cells by Sulfur‐Atmosphere Recrystallization Process

Abstract

Antimony sulfide (Sb 2 S 3 ) solar cells have attracted extensive attention in silicon‐based tandem solar cells. The performance of Sb 2 S 3 devices fabricated by the vacuum method is limited by sulfur vacancies ( V S ) and surface oxide defects during high‐temperature processes. Herein, amorphous Sb 2 S 3 film based on low‐temperature rapid thermal evaporation (RTE) technique is fabricated to overcome S loss. Moreover, a sulfur‐atmosphere recrystallization strategy is further developed to obtain high‐quality absorbers from the amorphous film. The element content of Sb 2 S 3 film is completely in accord with the stoichiometric ratio (2:3), and the surface oxides are effectively suppressed, enhancing V OC and fill factor. Compared to the control directly crystallized film, the defect concentrations of the S‐recrystallized Sb 2 S 3 film are reduced by 61%, exhibiting better uniformity and higher PN junction quality. Ultimately, the full‐inorganic Sb 2 S 3 solar cells (FTO/TiO 2 /Sb 2 S 3 /Au) achieve an efficiency of 6.25%. The S‐atmosphere recrystallization process can effectively passivate bulk defects ( V S and Sb 2 O 3 ) and suppress recombination to improve device performance, which will provide new prospects for vacuum method‐based Sb 2 S 3 thin film solar cells.