Organic electrochemical transistors (OECTs) are a promising technology in the field of bioelectronics. They bridge electronics and biology through their ability to operate in aqueous environments. Their ability to transduce biological signals into electronic ones makes them a preferred choice for bioelectronic applications, such as biosensing and neural interfaces. While p-type materials like PEDOT:PSS have become the benchmark for the OECT performance, the development of stable, high-mobility n-type channel materials remains a major challenge. These materials are often limited by poor air stability, low electron mobility, and restricted ionic transport. In this work, a newly developed semiconducting n-type polymer with cleavable side chains is investigated. The polymer, YYBC, undergoes a post-deposition thermal treatment, which leads to a porous, more hydrophilic polymer, YYAC. This cleaved version aims to improve the performance of an n-type OECT.
The research followed three main objectives. OECT devices were first fabricated in a cleanroom environment, then a measurement setup for steady-state and transient characterization was developed, and lastly, the new n-type polymer was evaluated. For device fabrication, standard microfabrication methods were employed. For the measurement setup, programmable source-measure units, a function generator, and an oscilloscope were controlled through MATLAB for data acquisition and analysis. Lastly, the performance of the n-type polymer was assessed using electrochemical and electrical characterization. Parameters such as volumetric capacitance, transconductance, and time response were evaluated.
Results of this work show that the post-deposition side-chain removal significantly improves the polymer’s electrochemical behaviour. The findings show improved performance metrics, indicating that the new n-type polymer can be a promising material for future OECT applications.