The prototypical chalcogenide perovskite, BaZrS3 (BZS), with its direct bandgap of 1.7–1.8 eV, high chemical stability, and strong light–matter interactions, has garnered significant interest over the past few years. So far, attempts to grow BaZrS3 films have been limited mainly to physical vapor deposition techniques. Here, we report the fabrication of BZS thin films via a facile aqueous solution route of polymer-assisted deposition (PAD), where the polymer-chelated cation precursor films were sulfurized in a mixed CS2 and Ar atmosphere. The formation of a single-phase polycrystalline BZS thin film at a processing temperature of 900 °C was confirmed by X-ray diffraction and Raman spectroscopy. The stoichiometry of the films was verified by Rutherford Backscattering spectrometry and energy-dispersive X-ray spectroscopy. The BZS films showed a photoluminescence peak at around 1.8 eV and exhibited a photogenerated current under light illumination at a wavelength of 530 nm. Temperature-dependent resistivity analysis revealed that the conduction of BaZrS3 films under the dark condition could be described by the Efros–Shklovskii variable range hopping model in the temperature range of 60–300 K, with an activation energy of about 44 meV.
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This content will become publicly available on July 1, 2025
Solution-based Sb2Se3 thin films for microphotonics
The development of functional chalcogenide optical phase change materials holds significant promise for advancing optics and photonics applications. Our comprehensive investigation into the solution processing of
Sb2Se3 thin films presents a systematic approach from solvent exploration to substrate coating through drop-casting methods and heat treatments. By employing characterization techniques such as scanning electron microscopy, dynamic light scattering, energy-dispersive X-ray spectroscopy, Raman spectroscopy, and X-ray diffraction, we reveal crucial insights into the structural, compositional, and morphological properties of the films as well as demonstrated techniques for control over these features to ensure requisite optical quality. Our findings, compared with currently reported deposition techniques, highlight the potential of solution deposition as a route for scalable Sb2Se3 film processing.
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- Award ID(s):
- 2225968
- NSF-PAR ID:
- 10525097
- Publisher / Repository:
- SPIE
- Date Published:
- Journal Name:
- Journal of Optical Microsystems
- Volume:
- 4
- Issue:
- 03
- ISSN:
- 2708-5260
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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