Development of High-Reliability and -Stability Chemical Sensors Based on an Extended-Gate Type Amorphous Oxide Semiconductor Thin-Film Transistor

We report a chemical sensor that exhibits high reliability and long-term stability; this is achieved by employing an amorphous oxide semiconductor (AOS) as a channel material in an extended-gate thin-film transistor (TFT). The results show that the developed In–W–Zn–O (IWZO) TFT exhibits high reliability even after continuous use. Further, the TFT demonstrates a stable response when deployed in an extended-gate structure with abundant charges. Additionally, the extended-gate IWZO-TFT is functionalized with a self-assembled monolayer that can identify weak molecular interactions between carboxylate and imidazole. Owing to these responses and durability characteristics, the high-reliability AOS-TFT is suitable for application in on-panel sensors.