Tsinghua University researchers have made high quality graphene sheets have been prepared by a facile liquid phase exfoliation of worm-like graphite (WEG). This approach combining with the advances in large scale industry manufacturing of WEG could potentially lead to the development of new and more effective graphene products.
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2. Etching of Graphene Devices with a Helium Ion Beam
We report on the etching of graphene devices with a helium ion beam, including in situ electrical measurement during lithography. The etching process can be used to nanostructure and electrically isolate different regions in a graphene device, as demonstrated by etching a channel in a suspended graphene device with etched gaps down to about 10nm. Graphene devices on SiO2 substrates etch with lower He ion doses and are found to have a residual conductivity after etching, which we attribute to contamination by hydrocarbons.
The full pdf copy of the ion beam etching of graphene.
Schematic of a graphene device. Inset: Photograph of the microscope chamber
with installed chip.