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arXiv · 2503.11691

Direct-Write Printed Contacts to Layered and 2D Materials

Abstract

Advancements in fabrication methods have shaped new computing device technologies. Among these methods, depositing electrical contacts to the channel material is fundamental to device characterization. Novel layered and two-dimensional (2D) materials are promising for next-generation computing electronic channel materials. Direct-write printing of conductive inks is introduced as a surprisingly effective, significantly faster, and cleaner method to contact different classes of layered materials, including graphene (semi-metal), MoS2 (semiconductor), Bi-2212 (superconductor), and Fe5GeTe2 (metallic ferromagnet). Based on the electrical response, the quality of the printed contacts is comparable to what is achievable with resist-based lithography techniques. These devices are tested by sweeping gate voltage, temperature, and magnetic field to show that the materials remain pristine post-processing. This work demonstrates that direct-write printing is an agile method for prototyping and characterizing the electrical properties of novel layered materials.

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Sharadh Jois, Erica Lee, Philip Li, Tsegereda Esatu, Jason Fleischer, Edwin Quinn, Genda Gu, Vadym Kulichenko, Luis Balicas, Son T. Le, Samuel W. LaGasse, Aubrey T. Hanbicki, Adam L. Friedman. 2025-03-06. Direct-Write Printed Contacts to Layered and 2D Materials. https://doi.org/10.1002/aelm.202400927

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