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Abstract Printed electronics have made remarkable progress in recent years and inkjet printing (IJP) has emerged as one of the leading methods for fabricating printed electronic devices. However, challenges such as nozzle clogging, and strict ink formulation constraints have limited their widespread use. To address this issue, a novel nozzle‐free printing technology is explored, which is enabled by laser‐generated focused ultrasound, as a potential alternative printing modality called Shock‐wave Jet Printing (SJP). Specifically, the performance of SJP‐printed and IJP‐printed bottom‐gated carbon nanotube (CNT) thin film transistors (TFTs) is compared. While IJP required ten print passes to achieve fully functional devices with channel dimensions ranging from tens to hundreds of micrometers, SJP achieved comparable performance with just a single pass. For optimized devices, SJP demonstrated six times higher maximum mobility than IJP‐printed devices. Furthermore, the advantages of nozzle‐free printing are evident, as SJP successfully printed stored and unsonicated inks, delivering moderate electrical performance, whereas IJP suffered from nozzle clogging due to CNT agglomeration. Moreover, SJP can print significantly longer CNTs, spanning the entire range of tube lengths of commercially available CNT ink. The findings from this study contribute to the advancement of nanomaterial printing, ink formulation, and the development of cost‐effective printable electronics.
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This content will become publicly available on October 17, 2026
Capillary Flow Printing of Submicrometre Carbon Nanotube Transistors
Printed transistors have a wide range of applications, but the limited resolution of printing techniques (10-30 µm) has been a barrier to their utility and scalability. Previous works have relied on chemical processes or tedious post-processing to realize printed submicron channel lengths, limiting their applicability. Here, we show that capillary flow printing can create as-printed submicron carbon nanotube thin-film transistors (CNT-TFTs) without chemical modification or physical manipulation post-printing. We show that the approach can be used to print conducting, semiconducting, and insulating inks on different types of substrates (silicon, Kapton, and paper), and can be used to fabricate various TFT device architectures. Printed CNT-TFTs yielded on-currents of 1.12 mA/mm when back gated on Si/SiO2, and 490 µA/mm when side gated through ion gel on Kapton. Mechanical bending and sweep rate resilience of devices on Kapton show the wide utility of these printed devices for flexible applications.
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- Award ID(s):
- 2245265
- PAR ID:
- 10639654
- Publisher / Repository:
- Nature Electronics
- Date Published:
- Journal Name:
- Nature electronics
- ISSN:
- 2520-1131
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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