Nanoparticle-dispersed high-k organic–inorganic hybrid dielectrics for organic thin-film transistors

We fabricated solution-processable thin gate dielectrics for organic thin-film transistors (OTFTs) using an organosiloxane-based organic–inorganic hybrid material. The electrical characteristics of the hybrid dielectrics were controlled by adjusting the zirconium alkoxide concentration. Microstructural observation and chemical analysis allow us to determine the influence of microstructure and composition on the electrical properties of the hybrid dielectrics. Our hybrid material is composed of three phases: ZrO2, ZrSiO4, and organosiloxane. OTFTs based on the hybrid dielectrics exhibited better electrical performance compared to transistors based on poly(4-vinylphenol) (PVP). Using a dielectric with a higher dielectric constant and fewer hydroxyl groups enabled us to fabricate a transistor with a lower off-current, higher on/off current ratio, and lower threshold voltage.