Simultaneous Imaging of a Graphite Surface with Atomic Force/Scanning Tunneling Microscope (AFM/STM)

We observed the graphite surface in air with an atomic force/scanning tunneling microscope (AFM/STM) system. We obtained atomically resolved AFM and STM images simultaneously under two types of operating modes. In the case of a constant height mode, the AFM (variable force) image showed the hexagonal pattern, while the STM (variable current) image showed the trigonal pattern. On the other hand, in the case of a constant current mode, the AFM (variable force) and STM (constant current) images showed the same trigonal pattern, but those patterns were out of phase with each other. We further investigated the effect of an oxide layer of a lever surface on simultaneous observation of AFM and STM images under the constant height mode.