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High-throughput printing-based fabrication has emerged as a key enabler of flexible electronics given its unique capability for low-cost integration of circuits based on printed thin film transistors (TFTs). Research in printing inorganic metal oxides has revealed the potential for fabricating oxide TFTs with an unmatched combination of high electron mobility and optical transparency. Here, we highlight recent developments in ink chemistry, printing physics, and material design for high-mobility metal oxide transistors. We consider ongoing challenges for this field that include lowering process temperatures, achieving high speed and high resolution printing, and balancing device performance with the need for high mechanical flexibility. Finally, we provide a roadmap for overcoming these challenges with emerging synthetic strategies for fabricating 2D oxides and complementary TFT circuits for flexible electronics.
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Advances in Liquid Metal Printed 2D Oxide Electronics
Abstract 2D metal oxides (2DMOs) have recently emerged as a high‐performance class of ultrathin, wide bandgap materials offering exceptional electrical and optical properties for a wide area of device applications in energy, sensing, and display technologies. Liquid metal printing represents a thermodynamically advantageous strategy for synthesizing 2DMOs by a solvent‐free and vacuum‐free scalable method. Here, recent progress in the field of liquid metal printed 2D oxides is reviewed, considering how the physics of Cabrera‐Mott oxidation gives this rapid, low‐temperature process advantages over alternatives such as sol‐gel and nanoparticle processing. The growth, composition, and crystallinity of a burgeoning set of 1–3 nm thick liquid metal printed semiconducting, conducting, and dielectric oxides are analyzed that are uniquely suited for the fabrication of high‐performance flexible electronics. The advantages and limitations of these strategies are considered, highlighting opportunities to amplify the impact of 2DMO through large‐area printing, the design of doped metal alloys, stacking of 2DMO to electrostatically engineer new oxide heterostructures, and implementation of 2D oxide devices for gas sensing, photodetection, and neuromorphic computing.
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- PAR ID:
- 10517311
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Advanced Functional Materials
- ISSN:
- 1616-301X
- Subject(s) / Keyword(s):
- liquid metal printing, 2D oxides, metal oxide semiconductors, transparent electronics
- 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/10.1002/adfm.202403619
