Observation of graphene bubbles and effective mass transport under graphene films

Mechanically exfoliated graphene mounted on a SiO$_{2}$/Si substrate was subjected to HF/H$_{2}$O etching or irradiation by energetic protons. In both cases gas was released from the SiO$_{2}$ and accumulated at the graphene/SiO$_{2}$ interface resulting in the formation of ``bubbles'' in the graphene sheet. Formation of these ``bubbles'' demonstrates the robust nature of single layer graphene membranes, which are capable of containing mesoscopic volumes of gas. In addition, effective mass transport at the graphene/SiO$_{2}$ interface has been observed.