Fabrication of graphene device from graphite intercalation compound

The mechanical exfoliation of graphite is possibly the simplest and practical method in laboratories to obtain graphene flakes for scientific research. However efficiency for obtaining graphene, with desired layer-number and size, depends largely on crystal specific characters, eg., dislocations. To improve the issue, we have adopted graphite intercalation compound (GIC) instead of graphite for a starting material. Generally, GIC is chemically active. We used SbCl$_5$- GIC, which is stable in the atmosphere. Stage structure of SbCl$_5$-GIC could be tuned by temperature of intercalation. We found that considerable number of undoped graphene flakes coexisted with thin SbCl$_5$-GIC flakes, on a substrate where flakes were transferred.?Statistical inspection of number of graphene layer indicated that it is significantly dependent on the stage number of GIC.