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Abstract PCPDTBT‐SO3K (CPE‐K), a conjugated polyelectrolyte, is presented as a mixed conductor material that can be used to fabricate high transconductance accumulation mode organic electrochemical transistors (OECTs). OECTs are utilized in a wide range of applications such as analyte detection, neural interfacing, impedance sensing, and neuromorphic computing. The use of interdigitated contacts to enable high transconductance in a relatively small device area in comparison to standard contacts is demonstrated. Such characteristics are highly desired in applications such as neural‐activity sensing, where the device area must be minimized to reduce invasiveness. The physical and electrical properties of CPE‐K are fully characterized to allow a direct comparison to other top performing OECT materials. CPE‐K demonstrates an electrical performance that is among the best reported in the literature for OECT materials. In addition, CPE‐K OECTs operate in the accumulation mode, which allows for much lower energy consumption in comparison to commonly used depletion mode devices.
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This content will become publicly available on July 18, 2026
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 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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- Award ID(s):
- 2219003
- PAR ID:
- 10623904
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Advanced Electronic Materials
- ISSN:
- 2199-160X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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