High-$k$ and low-$k$ nanocomposite gate dielectrics for low voltage organic thin film transistors

$CeO2–SiO2$ nanocomposite films were used as the gate dielectrics in organic thin film transistors (OTFTs) with pentacene active semiconductor. $CeO2–SiO2$ composite films exhibited a high dielectric capacitance of $57nF∕cm2$ with exceptionally low leakage current. Good device characteristics were obtained with saturation at low operating voltages $(∼2V)$ and with a field effect mobility of $0.84cm2V−1s−1$⁠, a threshold voltage of $∼0.25V$⁠, an on/off current ratio of $103$⁠, and a subthreshold slope of $0.3V∕decade$⁠, whereas the gate leakage current density is considerably lowered. These results should therefore increase the prospects of using OTFTs in low power applications such as portable devices.