SrTiO3 insulator for low-voltage organic field-effect transistors

Organic field-effect transistors (FETs) are considered to be used as high-end electronics and low-end ones. In the low-end electronics such as radio-frequency identification tags and smart-cards the devices should be battery-powered and then need to operate at a few volts. Majority of the organic FETs reported to date, however, can only operate well at a voltage as high as ∼100 V. Three kinds of approaches have been mainly proposed and studied in order to achieve low-voltage organic FETs. First one is simply using a high-k insulator to obtain certain electric capacitance at lower gate voltages. Second one is using a nanometer-thick self-assembled monolayer of organic compound as the gate dielectric. Third one is using a polymer composite containing ionic liquid. Here we briefly review typical studies using the three approaches to achieve the low-voltage organic FETs in the first part of this subject review, and then we focus on our recent progress in the low-voltage organic FETs mainly using strontium titanate as a high-k insulator in the second part.