Efficient planar antimony sulfide thin film photovoltaics with large grain and preferential growth

Compact thin film of antimony sulfide (Sb2S3) as a promising absorber layer was obtained by rapid thermal evaporation (RTE) rather than conventional chemical bath deposition or atomic layer deposition based methods. The systematical characterizations of Sb2S3 film demonstrated the pure phase, void free and high crystallization. The large grain and preferential growth of Sb2S3 thin film were implemented by crystallization and cooling techniques, respectively. The corresponding devices were gradually optimized with a power conversion efficiency of ~3.5%, almost three times of planar devices fabricated by vacuum method. Both the non-oxide buffer layer (CdS layer) and free of hole transport layer enabled the high stability of the non-encapsulated planar devices. The high throughput and reliable RTE fabrication technique, environment-friendly and earth-abundant Sb2S3 materials, stable and superior device performances were expected to drive the research progress of Sb2S3 thin film photovoltaics.