Structure, Morphology, and Photoelectric Performances of Te-Sb₂Se₃ Thin Film Prepared via Magnetron Sputtering

Antimony selenide (Sb₂Se₃) has been widely investigated as a promising absorber material for photovoltaic devices. However, low open-circuit voltage (V_oc) limits the power conversion efficiency (PCE) of Sb₂Se₃-based cells, largely due to the low-charge carrier density. Herein, high-quality n-type (Tellurium) Te-doped Sb₂Se₃ thin films were successfully prepared using a homemade target via magnetron sputtering. The Te atoms were expected to be inserted in the spacing of (Sb₄Se₆)_n ribbons based on increased lattice parameters in this study. Moreover, the thin film was found to possess a narrow and direct band gap of approximately 1.27 eV, appropriate for harvesting the solar energy. It was found that the photoelectric performance is related to not only the quality of films but also the preferred growth orientation. The Te-Sb₂Se₃ film annealed at 325 °C showed a maximum photocurrent density of 1.91 mA/cm² with a light intensity of 10.5 mW/cm² at a bias of 1.4 V. The fast response and recovery speed confirms the great potential of these films as excellent photodetectors.