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Abstract Chalcogenide optical phase change materials (PCMs) have garnered significant interest for their growing applications in programmable photonics, optical analog computing, active metasurfaces, and beyond. Limited endurance or cycling lifetime is however increasingly becoming a bottleneck toward their practical deployment for these applications. To address this issue, a systematic study elucidating the cycling failure mechanisms of Ge2Sb2Se4Te (GSST) is performed, a common optical PCM tailored for infrared photonic applications, in an electrothermal switching configuration commensurate with their applications in on‐chip photonic devices. Further a set of design rules building on insights into the failure mechanisms is proposed, and successfully implemented them to boost the endurance of the Ge2Sb2Se4Te (GSST) device to over 67 000 cycles.
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Solution-based processing of Ge 2 Sb 2 Se 4 Te optical phase change materials
Phase change materials (PCMs) are important building blocks in solid-state memory and photonic devices. Solution-based processing promises large-area, cost-effective, conformal coating of optical PCMs (O-PCMs) for photonic applications. In this work, a solution processing route was developed for Ge2Sb2Se4Te1(GSST), a target PCM of interest due to its large optical contrast, broadband transparency, and improved glass-forming capability. An alkahest solvent mixture of ethanedithiol and ethylenediamine was used as a solvent system to fabricate solution-derived GSST thin films and films from these solutions were prepared and characterized using SEM, XRD, and Raman spectroscopy.
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- Award ID(s):
- 2225967
- PAR ID:
- 10554590
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optical Materials Express
- Volume:
- 14
- Issue:
- 12
- ISSN:
- 2159-3930
- Format(s):
- Medium: X Size: Article No. 2874
- Size(s):
- Article No. 2874
- Sponsoring Org:
- National Science Foundation
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