▎ 摘　　要

Atomic-scale topography of epitaxial multilayer graphene grown on 4H-SiC(0001) was investigated using scanning tunneling microscopy (STM). Bunched nano-ridges ten times smaller than previously recorded were observed throughout the surface, the morphology of which was systematically altered using a relatively new technique called electrostatic-manipulation scanning tunneling microscopy. Transformed graphene formations sometimes spontaneously returned to their original morphology, while others permanently changed. Using an electrostatic model, we calculate that a force up to similar to 5 nN was exerted by the STM tip, and an energy of around 10 eV was required to alter the geometry of a similar to 100 x 200 nm(2) area. (c) 2013 The Japan Society of Applied Physics