Organic thin-film transistors with over 10 cm ² /Vs mobility through low-temperature solution coating

Recent studies on organic thin-film transistors (OTFTs) have reported high mobility values, but many of them showed non-ideal current–voltage characteristics that could lead to the overestimation of the mobility values. In this study, the non-ideal transistor behavior was briefly investigated by considering the effect of charge injection, and a method of overcoming the effect was developed. Correspondingly, various charge injection layers were developed, and their effects on the modification of metal contacts, including work function tuning and interfacial doping, were studied. The materials that had been coated formed a good metal-semiconductor interface through fine manipulation in the wetting and dewetting of the selected liquid. With such electrodes, the OTFTs were fabricated at room temperature and exhibited almost ideal transistor behavior in terms of the current–voltage characteristics, featuring high (over 10 cm2/Vs) field-effect mobility.