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Abstract Organic electrochemical transistors (OECTs) operate at very low voltages, transduce ions into electronic signals, and reach extremely large transconductance values, making them ideally suited for bio‐sensing applications. However, despite their promising performance, the dependence of their maximum transconductance on device geometry and applied voltages are not correctly captured by current capacitive device models. Here, current scaling laws are revised in the light of a recently developed 2D device model that adequately accounts for drift and diffusion of ions inside the polymer channel. It is shown that the maximum transconductance of the devices is found at the transition between the depletion and accumulation region of the transistors, which as well provides an explanation for the observed shift of the transconductance peak with geometric dimensions and the drain potential. Overall, the results provide a better understanding of the working mechanisms of OECTs, and facilitate design rules to optimize OECT performance further.
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Organic Electrochemical Transistors Based on the Conjugated Polyelectrolyte PCPDTBT‐SO 3 K (CPE‐K)
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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- Award ID(s):
- 1922042
- PAR ID:
- 10456409
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 32
- Issue:
- 33
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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