No matter how small electronic devices get, they still generate a lot of heat. At the nano- and micro-scales, interconnected wires and millions of mini transistors can create hot spots. And with heat, often comes damage.
For a couple of years, graphene has offered some hope to the electronics world as a material with an amazing ability to conduct and disperse heat.
Derived from graphite, graphene is a thin layer of carbon atoms connected within a lattice that resembles chicken wire. When I wrote “thin,” I meant it. Graphene is one-atom thick. But it’s mechanically strong, provides great electron mobility, and of course, has impressive thermal conductivity.
The problem with graphene? Producing large amounts of this small stuff at a certain quality is very difficult. So physicists and engineers have been working to somehow tap the material’s super-cooling powers.
Last month, researchers publishing in Science placed a layer of graphene on a silicon dioxide substrate (to right). Although the graphene lost a lot of its conducting ability through its interaction with the substrate, the results were promising.
The team found supported graphene still has thermal conductivity as high as 600 watts per meter per Kelvin near room temperature. That far exceeds the thermal conductivities of copper, approximately 250 watts, and silicon, only 10 watts, thin films currently used in electronic devices.
In a study published in Nature Materials on Sunday, physicists from University of California, Riverside found that layering a few graphene sheets on top of each other retains remarkable heat transferring properties. The additional levels decreased overall conductivity compared to the single-atom film, but multiple graphene sheets are apparently easier to make.
While graphene wouldn’t replace silicon, the materials could work well with each other within a microchip. Still, realizing graphene’s potential may take a few more years. Some possible applications for graphine’s thermal abilities include transparent electrodes in solar cells, heat spreaders within computer chips, and super-fast transistors for radio frequency communications.
Alexander Balandin, a UCR professor of electrical engineering, in a release:
Graphene is one of the hottest materials right now. Everyone is talking about it.
Images: WIkipedia, Boston College