Operation and modelling of diffusion-driven organic field-effect transistors for high-performance organic electronics

High-gain organic transistors are the key building blocks for the development of high-performance organic electronics, including high-sensitivity sensors, signal amplification in sensing systems and large-scale circuits. In this work, we analyze organic transistors based on the diffusion-driven charge-accumulation architecture. This class of organic field-effect transistors maximizes at the same the transconductance and the output resistance. The analysis is based on both electrical measurements and theoretical analysis. The transistor performances are critically compared with that of conventional organic field-effect transistors. A simple analytical model that accounts for the effect of the control drain on the saturation current is developed. The model is included in a circuit simulator and an active-load voltage amplifier with electrically-tunable gain is designed. The gain and bandwidth of the voltage amplifier are suitable for signal conditioning and amplification in organic smart sensors.