Organic electrochemical transistors (OECTs) have been hailed as a breakthrough in the field of electronics, particularly for brain-inspired and wearable technologies. These transistors have the ability to modulate electrical current in response to small changes in voltage applied to their gate electrode. Despite their promising capabilities, most conventional OECTs face limitations such as limited stability and slow redox processes, which can hinder their overall performance.
Researchers at Northwestern University have recently put forth a new strategy to address the limitations of conventional OECTs and to enhance their performance. This approach, detailed in a paper published in Nature Electronics, involves the fabrication of high-density and mechanically flexible OECTs using electron beam lithography (eBL). By exposing both p- and n-channel organic semiconductor films to a direct beam of electrons, the researchers were able to create ultra-small, high-density OECT arrays with well-defined conducting channel regions.
The use of eBL allowed for the production of patterned films that were electronically inactive yet retained their ability to conduct ions. The resulting OECT arrays exhibited impressive transconductances ranging from 0.08 to 1.7 S, transient times of less than 100 µs, and stable switching properties of more than 100,000 cycles. This represents a significant improvement over traditional OECTs and opens up new possibilities for their integration into electronic devices.
In addition to enhancing the performance of OECT arrays, the new fabrication strategy also enabled the creation of vertically stacked logic circuits based on OECTs. The researchers successfully implemented NOT, NAND, and NOR gates, all of which showcased exceptional performance and operational stability. This breakthrough has the potential to revolutionize the field of organic electronics and pave the way for the development of more advanced OECT circuits in the future.
The recent study conducted by Kim, Pankow, and their colleagues is a significant step forward in the advancement of OECT technology. By introducing a novel e-beam exposure strategy, the researchers have not only enhanced the stability and performance of OECT circuits but have also laid the groundwork for their scalable fabrication. This breakthrough could have far-reaching implications for the development of biosensors, wearable devices, and neuromorphic systems, marking a new chapter in the evolution of organic electronics.