Organic field-effect transistors containing a SiO ₂ nanoparticle thin film as the gate dielectric

In this article, we report the fabrication of organic field-effect transistors using self-assembled SiO ₂ as a gate dielectric material and pentacene as a semiconductor. The dielectric layer was self-assembled with 10 layers of SiO ₂ nanoparticles 45 nm in diameter, and its breakdown field was larger than 0.57 MV/cm. Being a low-cost and low-temperature process, the layer-by-layer self-assembly is particularly suitable for organic field-effect transistor fabrication. The pentacene was thermally evaporated on the substrate under high vacuum at the room temperature. The fabricated transistor has a threshold voltage of 0.3 V, field-effect mobility of 0.05 cm ²/Vs, and slope of 1.4 V/decade.