EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Dynamic surface modification of suspended graphene at high temperature was directly observed with in-situ scanning transmission electron microscope (STEM) measurement. The suspended graphene devices were prepared on top of the SiN membrane with hole substrate so that STEM observation was conducted under Joule heating processes. Current-voltage characteristics of suspended graphene devices inside of STEM chamber were measured to monitor and control the high temperature condition of graphene surface by estimating electrical power on the devices. During the in-situ STEM observation, it was found that residual materials remained on the graphene surface were removed at high temperature. Dynamic movement of residue on the graphene surface and shrinkage of atomic distance of graphene were also observed while the Joule heating process. The details of substrate and graphene device fabrication, STEM observation, and data analyses with simulation are described in this presentation.