Bi2NiMnO6(BNMO) epitaxial thin films with a layered supercell (LSC) structure have emerged as a promising single‐phase multiferroic material recently. Because of the required strain state for the formation of the LSC structures, most of the previous BNMO films are demonstrated on rigid oxide substrates such as SrTiO3and LaAlO3. Here, the potential of BNMO films grown on muscovite mica substrates via van der Waals epitaxy, spotlighting their suitability for cutting‐edge flexible device applications is delved. Comprehensive scanning transmission electron microscopy/energy‐dispersive X‐ray analyses reveal a layered structure in the BNMO film and a pristine interface with the mica substrate, indicating high‐quality deposition and minimal interfacial defects. Capitalizing on its unique property of easily cleavable layers due to weak van der Waals forces in mica substrates, flexible BNMO/mica samples are fixed. A standout feature of the BNMO film grown on mica substrate is its consistent multiferroic properties across varied mechanical conditions. A novel technique is introduced for thinning the mica substrate and subsequent transfer of the sample, with post‐transfer analyses validating the preserved structural and magnetic attributes of the film. Overall, this study illuminates the resilient multiferroic properties of BNMO films on mica, offering promising avenues for their integration for next‐generation flexible electronics.
This work provides the details of a simple and reliable method with less damage to prepare electron transparent samples for in situ studies in scanning/transmission electron microscopy. In this study, we use epitaxial VO2thin films grown on c‐Al2O3by pulsed laser deposition, which have a monoclinic–rutile transition at ~68°C. We employ an approach combining conventional mechanical wedge‐polishing and Focused Ion beam to prepare the electron transparent samples of epitaxial VO2thin films. The samples are first mechanically wedge‐polished and ion‐milled to be electron transparent. Subsequently, the thin region of VO2films are separated from the rest of the polished sample using a focused ion beam and transferred to the in situ electron microscopy test stage. As a critical step, carbon nanotubes are used as connectors to the manipulator needle for a soft transfer process. This is done to avoid shattering of the brittle substrate film on the in situ sample support stage during the transfer process. We finally present the atomically resolved structural transition in VO2films using this technique. This approach significantly increases the success rate of high‐quality sample preparation with less damage for in situ studies of thin films and reduces the cost and instrumental/user errors associated with other techniques.
The present work highlights a novel, simple, reliable approach with reduced damage to make electron transparent samples for atomic‐scale insights of temperature‐dependent transitions in epitaxial thin film heterostructures using in situ TEM studies.
more » « less- NSF-PAR ID:
- 10078216
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Microscopy Research and Technique
- Volume:
- 81
- Issue:
- 11
- ISSN:
- 1059-910X
- Page Range / eLocation ID:
- p. 1250-1256
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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