Semiconducting polymers are an unruly bunch, but University of Michigan engineers have developed a new method for getting them in line that could pave the way for cheaper, greener, “paint-on” plastic electronics.
“This is for the first time a thin-layer, conducting, highly aligned film for high-performance, paintable, directly writeable plastic electronics,” said Jinsang Kim, U-M professor of materials science and engineering, who led the research published in Nature Materials. Semiconductors are the key ingredient for computer processors, solar cells and LED displays, but they are expensive. Inorganic semiconductors like silicon require high temperatures in excess of 2,000 degrees Fahrenheit and costly vacuum systems for processing into electronics, but organic and plastic semiconductors can be prepared on a basic lab bench. The trouble is that charge carriers, like electrons, can’t move through plastics nearly as easily as they can move through inorganic semiconductors, Kim said. Part of the reason for this is because each semiconducting polymer molecule is like a short wire, and these wires are randomly arranged. “Charge mobility along the polymer chains is much faster than between the polymers,” Kim said. To take advantage of the good conduction along the polymers, research groups have been trying to align them into a charge-carrying freeway, but it’s a bit like trying to arrange nanoscopic linguine.
Read more at: Phys.org