Graphene Enhances Flexibility and Wearable Electronics
Graphene is an incredibly strong electrical and thermal conductor, making it a perfect ingredient to enhance semiconductor chips found in many electrical devices. There are, however, still roadblocks. Manufacturers have been unable to create large, industrially relevant amounts of the material. Research from the laboratory of Nai-Chang Yeh, the Thomas W. Hogan Professor of Physics, is reinvigorating efforts.
New studies demonstrate that graphene improves electrical circuits required for wearable and flexible electronics, including smart health patches, bendable smartphones, helmets, large folding display screens, and more.
In one study published in ACS Applied Materials & Interfaces, researchers grew graphene directly onto thin two-dimensional copper lines commonly used in electronics. Graphene improved conductive properties and protected the copper-based structures from the usual wear and tear. Graphene-coated copper structures, for example, can be folded 200,000 times without damage, compared to the original copper structures, which started cracking after 20,000 folds.
The second study, published in ACS Applied Nano Materials, demonstrated that gold coated in graphene can withstand sweat, making better implantable biosensors.
A third study in ACS Applied Materials & Interfaces shows that graphene can protect electrical circuits produced via inkjet printers. Researchers used plasma-enhanced chemical vapor deposition to grow high-quality graphene sheets, only one atom thick, at room temperature in about 15 minutes.
The researchers grew sheets of graphene in a basement laboratory. A ray of plasma, which glows pink, is used to activate a gas of hydrogen and methane molecules and break them down into smaller fragments. They then immerse the sample in the plasma, and the carbon from the gas gets deposited onto the surface in thin sheets that are one atom thick. The final surface with the graphene will appear shinier.
While graphene has taken more time to make its way into electronics than anticipated, it looks promising. It is key to the growing field of nanoelectronics, which aims to create smaller versions of the electronics widely used today. Graphene combined with silicon allows us to shrink devices to smaller and smaller sizes.
