The team has developed a promising new technique for creating graphene patterns on top of silicon carbide (SiC). SiC comprises both silicon and carbon, but at high temperatures (around 1300 degrees Celcius) silicon atoms will vaporize off the surface, leaving the carbon atoms to grow into sheets of pure graphene. Researchers had previously used this thermal decomposition technique to create large sheets of graphene, which were then etched to make the patterns required for devices. The etching process, however, can introduce defects or chemical contaminants that reduce graphene's prized electron mobility.
In contrast, the Florida team's technique allowed the researchers to confine the growth of graphene to a defined pattern as small as 20 nanometers. The team found that implanting silicon or gold ions in SiC lowered the temperature at which graphene formed by approximately 100 degrees Celcius. The team implanted ions only where graphene layers were desired, and then heated the SiC to 1200 degrees Celcius. At this temperature the pure SiC did not form graphene, but the implanted areas did. Using this technique, the team successfully created graphene nanoribbons, thin lines of graphene with nanoscale dimensions.
With further refining, the process, described in the American Institute of Physics' journal Applied Physics Letters, may be able to encourage selective graphene growth at even lower temperatures, the researchers write.
Article: "Drawing graphene nanoribbons on SiC by ion implantation" is published in Applied Physics Letters.
Authors: S. Tongay (1, 2), M. Lemaitre (1), J. Fridmann (3), A.F. Hebard (2), B.P. Gila (1), and B.R. Appleton (1).(1) Department of Material Science and Engineering, University of Florida
Catherine Meyers | EurekAlert!
Ultra-compact phase modulators based on graphene plasmons
27.06.2017 | ICFO-The Institute of Photonic Sciences
Smooth propagation of spin waves using gold
26.06.2017 | Toyohashi University of Technology
An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.
Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...
Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.
Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...
Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.
As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...
Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.
With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...
Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine
Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...
19.06.2017 | Event News
13.06.2017 | Event News
13.06.2017 | Event News
27.06.2017 | Power and Electrical Engineering
27.06.2017 | Information Technology
27.06.2017 | Physics and Astronomy