APPLICATIONS OF TECHNOLOGY:
- Nanoelectronics, e.g., nanotransistors
- Infrared optoelectronics
- Facilitates the use of graphene for nanoscale electronics and photonics
- Enables tunable electronic and optical performance in situ
- Works at room temperature
- No need for chemical doping
Berkeley Lab researchers have developed a tunable electronic bandgap in bilayer graphene that spans a spectral range from zero to 250 meV (mid-infrared range). In essence, the invention causes graphene to behave like a semiconductor, but at a narrower bandgap than silicon or gallium arsenide.
The technology consists of a bilayer graphene device with two gate electrodes. Bandgap size and the graphene’s degree of charge doping can be controlled by independently adjusting the voltage at the two gates. The device operates at room temperature and without chemical doping, making it compatible with device applications.
Single-layer graphene has no bandgap, a feature that impedes its use in electronic and photonic applications since bandgap determines, in large part, the transport and optical qualities of semiconductors and insulators. By creating a tunable band gap, Berkeley Lab researchers have opened a door to greater flexibility in designing and optimizing nanoelectronic and nanophotonic devices.
DEVELOPMENT STAGE: Proven principle.
STATUS: Published Patent Application 20110006837 available at www.uspto.gov. Available for licensing or collaborative research.
FOR MORE INFORMATION:
Preuss, Paul. Bilayer Graphene Gets a Bandgap, Berkeley Lab News Center, June 10, 2009.
Zhang, Yuanbo, Tang, Tsung-Ta, Girit, Caglar, Hao, Zhao, Martin, Michael, Zettl, Alex, Commie, Michael, Shen, Y. Ron. Wang, Feng. Direct Observation of a Widely Tunable Bandgap in Bilayer Graphene. Nature, 459, pp. 820-823, 2009.
REFERENCE NUMBER: JIB-2739