▎ 摘　　要

The three-dimensional information of atomic positions is required to determine the atomic structure of materials. However, images obtained using high-resolution transmission electron microscopes are generally two-dimensional projections of three-dimensional structures. The depth resolution of general microscopes is still on the order of nanometers, and a smaller depth of field is required to realize atomic depth-resolution imaging. Here, we propose highly depth-sensitive imaging using a low-voltage atomic-resolution transmission electron microscope equipped with a higher order geometrical aberration corrector and a monochromator. A long wavelength of low energy electrons and a large acceptance angle of the microscope allow for a shallow depth of field and atomic-level depth sensitivity. We demonstrate that the depth resolution and depth precision can allow for angstrom and sub-angstrom levels, respectively. Applying this highly depth-sensitive microscope, the depth deviation of monolayer graphene with dislocations is detected as the difference of defocus. The buckling structures of dislocation dipole and tripole are directly observed using a single image. Combining the proposed depth-sensitive microscope with through-focal imaging will allow for the analysis of various low-dimensional materials in three dimensions with atomic depth resolution. Published by AIP Publishing.