Electrically stable organic thin-film transistors and circuits using organic/inorganic double-layer insulator

Pentacene-based organic thin-film transistors (OTFTs) and organic circuits are fabricated using a plasma-enhanced chemical vapor deposition (PECVD) SiO₂/cross-linked poly(vinyl alcohol) (PVA) double-layer insulator. A considerable reduction in hysteresis is achieved by optimizing the double-layer insulator thickness. The main mechanism of a low hysteresis is attributed to the balance of the injected electrons and induced holes at the interface. The fabricated devices have several advantages including low hysteresis characteristics and a stable performance. On the basis of the proposed OTFTs, an electrically stable organic inverter and a buffer working at a frequency as high as 1 kHz are fabricated.