Engineering Semiconductor Layer Using Halonaphthalene Additives for Organic Opto-Inverter Circuits

Abstract

Solution-processable organic field-effect transistors (OFETs) are at the forefront of the future of electronic circuits. They have the potential for low-cost, large-scale fabrication on a variety of substrates. However, their application in electronic circuits is challenged by the unforeseen presence of defects leading to lower mobility. In this contribution, the application of a photoactive polymer-based phototransistor in a digital electronic circuit is demonstrated. Initially, a solvent additive engineering strategy is adopted to tune the thin film morphology and reduce morphology-related defects, resulting in improved device performance. The incorporation of 1-bromonaphthalene improves mobility from 0.09 to 0.50 cm2 V–1 s–1 with enhancement in both photoabsorption and photostability. The results are well supported by electrical characterization and photophysical and morphological studies. Thereafter, a unique architecture of an opto-inverter is presented using the OFET. In this work, an optoelectronic logic NOT gate is also fabricated by utilizing a simple resistive load circuit. This circuit is also demonstrated to perform the combined functionality of a logic gate and a transducer. Furthermore, this technique can be easily implemented for minimizing the circuit components and complexity by replacing a photodetector and a NOT gate with a single opto-inverter in applications requiring both.