Materials scientists at the University of Massachusetts Amherst have investigated how micro-scale wrinkling affects electrical performance in carbon based, single crystal semiconductors and believe the work could have application in wearable electronics.
Post doctoral student Marcos Reyes-Martinez said: "We worked with a crystalline semiconductor called rubrene – a carbon based material that has performance factors, such as charge-carrier mobility, surpassing those measured in amorphous silicon."
According to the team, organic semiconductors are an interesting alternative to silicon; adding that devices based on organic semiconductors do not require high temperatures, clean rooms and expensive processing steps.
Until now, Reyes-Martinez noted, most researchers have focused on controlling the detrimental effects of mechanical deformation on a transistor's electrical properties. However, the team discovered that mechanical deformations only decrease performance under certain conditions, and can actually enhance performance in other cases.
"Our goal was not only to show these effects, but also to explain and understand them," Reyes-Martinez continued. "What we've done is take advantage of the ordered structure of ultra thin organic single crystals of rubrene to fabricate high perfomance, thin-film transistors."
The team found that crystals ranging in thickness from about 150nm to 1µm could be wrinkled and applied to any elastomer substrate. Reyes-Martinez said: "Our experiments are important because they help scientists working on flexible electronic devices to determine performance limitations of new materials under extreme mechanical deformations, such as when electronic devices conform to skin."
Author
Graham Pitcher
Source: www.newelectronics.co.uk