Self-assembling organic thin-film transistors

Organic thin-film transistor (OTFT) dielectric layers that selfassemble and enable transistor function at low voltages have been developed by a team of chemists. Myung-Han Yoon et al. developed working transistors that employ organosilane-based dielectric layers that organize themselves from solution. The resulting dielectric films are 2.3–5.5 nm thick, smooth, and nearly defect-free. The films are comprised of cross-linked multilayers that, in turn, are composed of layers of crosslinked hydrocarbon chains or stilbazolium groups with an octachlorotrisiloxane cap. These dielectrics have large electrical capacitances and favorable insulating properties, which are the hallmarks of dielectrics used with inorganic semiconductors. OTFTs fabricated with the self-assembled dielectrics in combination with a variety of organic semiconductors function at 1 V, a much greater efficiency than previous OTFTs, which typically operate in the technically and commercially unfeasible 30to 100-V range. The team showed that these dielectrics are compatible with both vaporand solutiondeposited pand n-channel organic semiconductors. OTFTs have potential applications in mechanically f lexible printed logic circuits that could be used in displays, sensors, and radio frequency ID tags.