Post‐deposition annealing and interfacial atomic layer deposition buffer layers of Sb₂Se₃/CdS stacks for reduced interface recombination and increased open‐circuit voltages

Abstract Currently, Sb 2 Se 3 thin films receive considerable research interest as a solar cell absorber material. When completed into device stack, the major bottleneck for further improvement is open‐circuit voltage, which focus of work presented here. Polycrystalline thin‐film absorbers and cells are prepared in substrate configuration dominant recombination path studied using photoluminescence spectroscopy temperature‐dependent current–voltage characteristics. It found that post‐deposition annealing after CdS buffer layer deposition can effectively remove interface since activation energy becomes equal to bandgap absorber. The increased accompanied by an yield, is, reduced non‐radiative recombination. Finished devices reach voltages high 485 mV. Contrarily, short‐circuit current density these limiting efficiency annealing. shown atomic layer‐deposited intermediate layers such TiO or S pave way overcoming this limitation.