AFM image of crystallographic structure of a sheet of graphene. Credit: Jarillo-Herrero group
A recent article in MIT Tech Talk describes aspects of several exciting graphene research projects at MIT.
A successor to silicon? Graphene could become the successor to silicon in a new generation of microchips because of its unique electrical characteristics. Graphene could surmount the basic physical constraints that limit further development of smaller, faster chips.
Transparent electrodes? Pure graphene is transparent because of its single-atom thickness. Therefore, it can be used to make transparent electrodes for light-based applications, such as LEDs or solar cells.
Substitute for copper? Graphene also could substitute for copper to make the electrical connections between computer chips and other electronic devices. This would provide lower resistance and generate less heat.
AFM of graphene superconducting FET. The two gold-colored electrodes are made of superconducting titanium-aluminum alloy. Credit: Jarillo-Herrero group
Study quantum-mechanical effects? A team led by Pablo Jarillo-Herrero, an assistant professor of physics, is studying its basic physical properties and using graphene’s unique behavior as a way to study fundamental quantum-mechanical effects. For example, in graphene, electrons behave as if they were massless particles that propagate according to the laws of relativistic quantum mechanics, a behavior that is normally reserved to particles traveling near the speed of light in accelerators or in the cosmos. Such behavior is at the heart of the ultrahigh mobilities exhibited by graphene devices. Jarillo-Herrero says that because the material is so new and its fundamental properties still being discovered, “we have some applications in mind, but many totally new ones will for sure come up as we continue doing research.”
Graphene production? Another team, led by Jing Kong, the ITT Career Development Associate Professor of Electrical Engineering, is working on developing commercial methods to produce the material in greater quantities. The team has created sheets of graphene by chemical vapor deposition. Kong’s method uses equipment that is “very compatible to conventional semiconductor processing.” The method “is quite straightforward, and not too expensive,” she says. That’s good news for commercial applications. For specialized functions, such as computer chips, further research will be needed to improve the quality and uniformity of the graphene sheets, she says, but for other applications, such as solar-cell electrodes, the existing process allows the researchers to start the investigation.
The MIT article also includes an excellent review of the structure, properties and history of graphene.