Threshold Voltage Control in Dual-Gate Organic Electrochemical Transistors

TL;DR

This paper introduces dual-gate PEDOT:PSS-based organic electrochemical transistors with adjustable threshold voltage, enabling improved circuit design and operation modes for bioelectronic applications.

Contribution

It demonstrates a novel dual-gate configuration allowing seamless threshold voltage control during operation, enhancing device flexibility and performance.

Findings

Threshold voltage tuning linearly depends on gate capacitance.

Devices can operate in accumulation mode, simplifying circuit design.

Dual-gate structure improves device performance and control.

Abstract

Organic electrochemical transistors (OECTs) based on Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonic acid) (PEDOT:PSS) are a benchmark system in organic bioelectronics. In particular, the superior mechanical properties and the ionic-electronic transduction yield excellent potential for the field of implantable or wearable sensing technology. However, depletion-mode operation PEDOT:PSS-based OECTs cause high static power dissipation in electronic circuits, limiting their application in electronic systems. Hence, having control over the threshold voltage is of utmost technological importance. Here we demonstrate PEDOT:PSS-based dual-gate OECTs with solid-state electrolyte where the threshold voltage is seamlessly adjustable during operation. We show that the degree of threshold voltage tuning linearly depends on the gate capacitance, which is a straightforward approach for circuit designers to adjust the threshold voltage only by the device dimensions. The PEDOT:PSS-based dual-gate OECTs show excellent device performance and can be pushed to accumulation-mode operation, resulting in a simplified and relaxed design of complementary inverters.