Silver antimony sulfide thin films and its selenization on stainless steel substrates by chemical bath deposition

Abstract In this study, 304 stainless steel (SS304) substrates were used for the first time for the deposition of cubic silver antimony sulfide selenide (AgSb(S, Se) 2 ) films. The AgSbS 2 films were deposited using chemical bath deposition (CBD) followed by a one-step selenization process. Amorphous AgSbS 2 films were produced through two sequential chemical depositions carried out over 4 h at 2 °C. The transformation from the amorphous state to cubic AgSb(S, Se) 2 was achieved via selenization under ambient air conditions. Grazing incidence x-ray diffraction (GIXRD) confirmed the formation of cubic AgSbS 1.7 Se 0.3 and AgSbS 1.5 Se 0.5 solid solutions, with a calculated crystal size of approximately 9 nm. Raman spectroscopy revealed the amorphous nature of the as-deposited AgSbS 2 films, with an asymmetric band observed at 331 cm −1 , while polycrystalline AgSb(S, Se) 2 films exhibited vibrational modes at 147, 190, 205, 253, 270, 324, and 493 cm −1 . Scanning electron microscopy (SEM) analysis indicated a transformation of the granular morphology of AgSbS 2 films into a smoother surface upon selenization. Energy dispersive spectroscopy (EDS) detected selenium incorporation up to 11.4 atomic percent (at%) in the AgSbS 1.5 Se 0.5 film. The optical band gap ( E g ) was modulated from 1.71 eV to 1.47 eV, depending on the selenium content introduced through selenization. The C/SS304/AgSb(S, Se) 2 /C structure fabricated on stainless steel substrates exhibited ohmic contact, suggesting its potential for application in flexible solar cells.