title: Assessment of lower-voltage TEM performance using 3D Fourier transform of through-focus series.
abstract: We assess the imaging performance of a transmission electron microscopy (TEM) system operated at a relatively low acceleration voltage using the three-dimensional (3D) Fourier transform of through-focus images. Although a single diffractogram and the Thon diagram cannot distinguish between the linear and non-linear TEM imaging terms, the 3D Fourier transform allows us to evaluate linear imaging terms, resulting in a conclusive assessment of TEM performance. Using this method, information transfer up to 98 pm is demonstrated for an 80 kV TEM system equipped with a spherical aberration corrector and a monochromator. We also revisit the Young fringe method in the light of the 3D Fourier transform, and have found a considerable amount of non-linear terms in Young fringes at 80 kV even from a typical standard specimen, such as an amorphous Ge thin film.
authors.affiliation: National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan. kimoto.koji@nims.go.jp
authors.forename: Koji
authors.initials: K
authors.lastname: Kimoto
authors.forename: Keiji
authors.initials: K
authors.lastname: Kurashima
authors.forename: Takuro
authors.initials: T
authors.lastname: Nagai
authors.forename: Megumi
authors.initials: M
authors.lastname: Ohwada
authors.forename: Kazuo
authors.initials: K
authors.lastname: Ishizuka