Science and Technology
Science and Technology
Nanostructured Gate Dielectric Boosts Stability of Organic Thin-Film Transistors
January 12, 2018
• Atlanta, GA
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Image shows organic-thin film transistors with a nanostructured gate dielectric under continuous testing on a probe station. (Credit: Rob Felt, Georgia Tech)
A nanostructured gate dielectric may have addressed the most significant obstacle to expanding the use of organic semiconductors for thin-film transistors. The structure, composed of a fluoropolymer layer followed by a nanolaminate made from two metal oxide materials, serves as gate dielectric and simultaneously protects the organic semiconductor – which had previously been vulnerable to damage from the ambient environment – and enables the transistors to operate with unprecedented stability.
The new structure gives thin-film transistors stability comparable to those made with inorganic materials, allowing them to operate in ambient conditions – even underwater. Organic thin-film transistors can be made inexpensively at low temperature on a variety of flexible substrates using techniques such as inkjet printing, potentially opening new applications that take advantage of simple, additive fabrication processes.
“We have now proven a geometry that yields lifetime performance that for the first time establish that organic circuits can be as stable as devices produced with conventional inorganic technologies,” said Bernard Kippelen, the Joseph M. Pettit professor in Georgia Tech’s School of Electrical and Computer Engineering (ECE) and director of Georgia Tech’s Center for Organic Photonics and Electronics (COPE). “This could be the tipping point for organic thin-film transistors, addressing long-standing concerns about the stability of organic-based printable devices.”
The research was reported January 12 in the journal Science Advances. The research is the culmination of 15 years of development within COPE and was supported by sponsors including the Office of Naval Research, the Air Force Office of Scientific Research, and the National Nuclear Security Administration.
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