Reversibly Bendable Pyrolytic Graphite Film and its Electronic Properties

A reversibly bendable graphite film has been prepared by the pyrolysis of a polyimide film at 2800°C. The graphite film can be bent reversibly and repeatedly by about 30° without inducing cracks on its surface. In addition, there is no variation of residual resistivity ratio and magnetoresistance, which are the index of the crystallinity, even with more than 100 bendings by about 30°. On the other hand by bending by more than 30° repeatedly, residual resistivity ratio and magnetoresistance slightly decreased. These results were interpreted by taking bending-induced defects in the graphite film into account.