The key to wearable electronics Wednesday, 07 October 2015

Researchers from Monash University and the Australian Synchrotron have helped produce the highest frequency organic transistor in the world, creating the potential to develop subtle electronic products such as ID badges woven into clothing, translucent solar panels on windows and virtually invisible electronic sensors and monitors.

The researchers contributed to work at the Center for Nano Science and Technology in Milan into printing large-scale semiconductor sheets using the polymer P(NDI20D-T2).

Associate Professor Chris McNeill, from the Monash University Department of Materials Science and Engineering, said their new ‘bar-coating’ technique uses the discovery that molecules in the polymer must be precisely aligned.

"Many research teams have attempted roll-out printing of the polymer into sheets, much like a mound of dough is rolled flat by a rolling pin, but this has led to lackluster transistor performance," McNeill said.

"Tightly wrapping a wire around the 'rolling pin' bar creates a coat of microscopic grooves 50 microns wide – one twentieth of a millimetre – forcing the molecules of the polymer into an organised pattern during printing, for much greater conductivity."

He said, using the Australian Synchrotron’s Soft X-ray Spectroscopy (SXR) beamline, they defined the optimal molecular structure of the polymer, which enabled the Italian team to print an organic transistor eight times larger than any predecessor, and boasting a commercially competitive frequency of 3.3 MHz.

"We believe the upscaling of organic transistors will enable faster development of next-generation electronics that are pliable, malleable and more affordable, beyond the limitations of bulky silicon-based transistors," he said.

 

Chris McNeill with the new polymer. Photo: Australian Synchrotron.