Printed Organic Electronics with a High-K Nanocomposite Dielectric Gate Insulator

High capacitance, solution processed nanocomposite dielectric material was demonstrated as a gate insulator for printed electronics applications. A nanocomposite consisting of cross-linked propylene glycol methyl ether acetate and barium titanate (BTO) nanoparticles was developed and utilized as the gate insulator. The high relative permittivity (K=35), bimodal nanocomposite utilized had two different filler particle sizes 200 nm and 1000 nm diameter particles. Bottom contact organic field effect transistors (OFETs) were demonstrated using a combination of printing and spray coating technologies. A metal coated plastic film was used as the flexible gate substrate. An amorphous organic semiconductor was utilized as the active layer. OFETs with the solution processed nanocomposite dielectric had a high field-induced current and a low threshold voltage and thus a low operating voltage due to the high capacitance gate insulator. In this paper, we review the characteristics of the nanocomposite material and discuss the processing and performance of the printed organic devices.