Possible graphene replacement found

A team from universities in Berlin and Marseille and research institutes in Rome and Saint Aubin, France has published a paper in Physical Review Letters that claims to show evidence of the synthesis of epitaxial silicene sheets on a silver (111) substrate.

The researchers have reported the growth of a single layer of silicon on top of silver, in a hexagonal 2D form of silicon similar to the graphene form of carbon.

Silicon and carbon both have four valence electrons, which means that the two elements should be able to demonstrate a degree of similarity including the possibility of silicon-based life forms and carbon-based conductors and semiconductors.

Graphene has attracted much attention recently because it offers higher electron mobility than materials used to date in silicon-based transistors. However, before it has reached commercial deployment if could be rivalled its silicon equivalent, especially because of the inherent compatibility silicene has with silicon-based electronics and how easily it could be used in wafer fabs.

Academics speculated about the possible synthesis of silicene in 2010 and some claimed to have seen structures suggestive of silicene. The team from Technical University Berlin, Aix-Marseille University, CNR-ISM Rome and Synchrotron Soleil in Saint Aubin, France state in the abstract to the Physical Review Letter that their evidence, based on a combination of scanning tunneling microscopy and angular-resolved photoemission spectroscopy in conjunction with calculations based on density functional theory, is compelling.

Silicene is thought to differ from graphene by having a rippled surface but the electronic properties of silicene nanoribbons and sheets are said to resemble those of graphene, according to a review of silicene published by another team.

- Peter Clarke
??EE Times