Enhanced Sb₂S₃ crystallisation by electric field induced silver doping

This work reveals that doping Ag into Sb₂S₃ substantially decreases its crystallisation temperature. We show that applying an electric field to Sb₂S₃ through Ag electrodes provides control of the crystallisation temperature and crystallisation rate. The crystal nuclei incubation time decreases substantially when the applied electric field is set to 200 kV/m. The applied electric field appears to force the Ag cations through the amorphous chalcogenide film resulting in Ag doped Sb₂S₃ filaments that extend from the cathode to the anode. This was confirmed by X-ray fluorescence composition mapping. Density functional theory molecular dynamics modelling of Ag doped Sb₂S₃ reveals that the diffusion constant of Ag is twice that of Sb or S over a wide temperature range, which implies that the Ag atoms are mobile in the amorphous Sb₂S₃ structure. The applied electric field provides a mechanism to enhance the crystallisation kinetics of Ag-doped Sb₂S₃.