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Utilizing an interplay between band topology and intrinsic magnetism, the two-dimensional van der Waals (vdW) system MnBi2Te4 provides an ideal platform for realizing exotic quantum phenomena and offers great opportunities in the emerging field of antiferromagnetic spintronic technology. Yet, the fabrication of MnBi2Te4-based nanodevices is hindered by the high sensitivity of this material, which quickly degrades when exposed to air or to elevated temperatures. Here, we demonstrate an alternative route of fabricating vdW-MnBi2Te4-based electronic devices using the cryogenic dry transfer of a printable circuit embedded in an inorganic silicon nitride membrane. The electrical connections between the thin crystal and the top surface of the membrane are established through via contacts. Our magnetotransport study reveals that this innovative via contact approach enables exploring the MnBi2Te4-like sensitive 2D materials and engineering synthetic heterostructures as well as complex circuits based on the two-dimensional vdW systems.
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Contact engineering for 2D materials and devices
Over the past decade, the field of two-dimensional (2D) layered materials has surged, promising a new platform for studying diverse physical phenomena that are scientifically intriguing and technologically relevant. Contacts are the communication links between these 2D materials and the three-dimensional world for probing and harnessing their exquisite electronic properties. However, fundamental challenges related to contacts often limit the ultimate performance and potential of 2D materials and devices. This article provides a comprehensive overview of the basic understanding and importance of contacts to 2D materials and various strategies for engineering and improving them. In particular, we elucidate the phenomenon of Fermi level pinning at the metal/2D contact interface, the Schottky versus Ohmic nature of the contacts and various contact engineering approaches including interlayer contacts, phase engineered contacts, and basal versus edge plane contacts, among others. Finally, we also discuss some of the relatively under-addressed and unresolved issues, such as contact scaling, and conclude with a future outlook.
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- Award ID(s):
- 1640020
- PAR ID:
- 10066926
- Date Published:
- Journal Name:
- Chemical Society Reviews
- Volume:
- 47
- Issue:
- 9
- ISSN:
- 0306-0012
- Page Range / eLocation ID:
- 3037 to 3058
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/C7CS00828G
