# Close Space Sublimation Growth of Sb2(S,Se)3 Thin-Film Solar Cells

## TL;DR

This paper explores using a CSS method to grow Sb2(S,Se)3 thin films for solar cells, achieving moderate efficiency but identifying sulfur loss as a key issue.

## Contribution

The study introduces a CSS method for Sb2(S,Se)3 thin films and identifies sulfur loss as a critical limitation for device performance.

## Key findings

- CSS method achieved up to 4.3% power conversion efficiency with open-circuit voltages over 490 mV.
- Sulfur loss during deposition caused oxide formation and increased series resistance.
- Discrepancies were found between bandgap measurements and sulfur content estimates.

## Abstract

This study reports
the synthesis and characterization of Sb2(S,Se)3 thin films for thin-film photovoltaics
via a single-source close space sublimation (CSS) approach. We demonstrate
power conversion efficiencies of up to 4.3% with notable improvements
in open-circuit voltage (V
oc >490 mV)
compared to those of Sb2Se3 equivalents. Secondary
ion mass spectrometry, X-ray diffraction, and cross-sectional scanning
and transmission electron microscopies identified some issues in controlling
film stoichiometry, particularly with sulfur loss, leading to oxide
formation and elevated series resistance, reducing the fill factor
in completed devices. We also identify clear discrepancies between
the determined bandgap, sulfur content inferred from X-ray diffraction
analysis, and sulfur content of the synthesized source material. We
conclude that while CSS is a promising method for Sb2(S,Se)3 film fabrication, addressing sulfur loss during deposition
is crucial to achieving further improvements in device efficiency.