APPLICATIONS OF TECHNOLOGY:
- Production of device-sized (micrometer-scale) graphene
- No hazardous materials required
- Ease of synthesis
- Improved homogeneity of graphene compared with conventional synthesis methods
Researchers at Berkeley Lab have developed a technology for synthesizing high quality, micrometer scale graphene layers on silicon carbide wafers in a thermal process. The thickness of the graphene is controlled by controlling the annealing temperature and duration of heating.
With two wafers facing each other in close proximity, in a first vacuum heating stage, while maintained at a vacuum of around 10-6 Torr, the wafer temperature is raised to about 1500C, whereby silicon evaporates from the wafer leaving a carbon rich surface, the evaporated silicon trapped in the gap between the wafers, such that the higher vapor pressure of silicon above each of the wafers suppresses further silicon evaporation. As the temperatures of the wafers is raised to about 1530C or more, the carbon atoms self-assemble into graphene.
Graphene shows promising potential for a wide variety of technological applications such as post-CMOS digital electronics, single-molecule gas sensors, and spintronic devices, among others. For graphene to be successfully applied to new devices, homogeneous growth of graphene with device-sized scale (micrometer) on a semiconducting or insulating substrate is essential.
STATUS: Issued U. S. Patent No. 8,142,754 available at www.uspto.gov.
SEE THESE OTHER BERKELEY LAB TECHNOLOGIES IN THIS FIELD:
Compact Microchip Gas Sensor, JIB-2689
Atomically Flat Crystal Surfaces, IB-2549
REFERENCE NUMBER: IB-2831