Graphene is the perfect structure to grow GaN micro-rods for flexible devices

Researchers from Seoul National University managed to grow gallium nitride (GaN) micro-rods on a graphene sheet. This enabled them to create transferable LEDs and may enable the fabrication of bendable and stretchable devices.

The researchers say that graphene is the "perfect substrate" because it provides the desired flexibility with excellent mechanical strength, and it's also chemically and physically stable at temperatures in excess of 1,000 degrees Celsius. GaN combined with graphene substrates also shows excellent tolerance for mechanical deformation.

To create those GaN microstructure LEDs, the researchers uses a catalyst-free metal-organic chemical vapor deposition (MOCVD) process they developed back in 2002. Their technique maintains high crystallinity, control over doping, formation of heterostructures and quantum structures. It results in vertically aligned growth onto the underlying graphene.

The researchers further report that there was no significant degradation in optical performance after 1,000 bending cycles.

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Posted: Sep 24,2014 by Ron Mertens