Electronic devices can't work well unless all of the transistors, or switches, within them allow electrical current to flow easily when they are turned on.

A team of engineers has determined why some transistors made of organic crystals don't perform well, yielding ideas about how to make them work better.

The research, which could help engineers design better digital displays and other devices, was published online Nov. 8 in the journal Nature Materials.

Organic semiconductors have a lot to offer in electronics. They are cheap and flexible, and the production process is much simpler than for traditional silicon chips. Applications such as computer display screens, digital signs or magazines made of "electronic paper" have been possibilities for more than a decade, but their full potential seems always just around the corner. A persistent problem is that performance from transistor to transistor varies much more than can be allowed in commercially viable devices.

"You can make a single device that has high 'charge mobility,' but you really need to make thousands of them," said Alberto Salleo, an assistant professor of materials science and engineering at Stanford and a senior co-author of the paper. "Most research groups report a high variation in that mobility. What we did here is try to understand what causes the variation."

"Engineered organic semiconductor crystals such as these are used to study the effects of current flow in thin film transistors that could be useful in digital displays and flexible electronics. (Credit: Image courtesy of Stanford University)"

Source: Stanford University