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

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.