Method Lops Years off Organic Semiconductor Development Process

Imagine if you could roll up an iPad — or any other tablet-esque display — like a yoga mat and tuck it into your back pocket or under your arm for ease of transport. Researchers at Stanford University and at Harvard University in Cambridge, Mass., have developed an organic semiconductor material that is among the speediest yet and that may someday make roll-up flexible displays possible.

The scientists accelerated the development process by employing a predictive technique that lopped off many months — and possibly years — from the typical time line to develop organic electronic materials. For the most part, developing materials such as these is a time-sensitive, hit-or-miss process that requires researchers to synthesize large numbers of candidate material and test them through a process of trial and error.

A single crystal of the new organic semiconductor material shown in polarized light. It is approximately twice as fast as the parent organic material from which it was derived. The white scale bar at the bottom center of the image represents 10 µm. (Image: Anatoliy Sokolov)

Currently, semiconductors are made from inorganic materials — commonly silicon — which are fast and durable, but these materials do not bend. As a starting point, the scientists chose to use a material known as DNTT, which has already been shown to be a good organic semiconductor. The researchers applied combinations of other compounds they felt possessed chemical and electrical properties that seemed likely to enhance the parent material’s performance if they were attached. In doing so, they discovered seven potential candidates.

“It would have taken several years to both synthesize and characterize all the seven candidate compounds,” said Zhenan Bao, an associate professor at Stanford. “With this approach, we were able to focus on the most promising candidate with the best performance, as predicted by theory. This is a rare example of truly ‘rational’ design of new high-performance materials.”

The scientists hope that their predictive approach will serve as a blueprint for other research groups who are working to find better organic semiconductors. In addition, they are eager to apply their method to the development of new, high-efficiency material for organic solar cells.

The team’s findings appeared in the Aug. 16 issue of Nature Communications.

For more information, visit: www.stanford.edu