Assessment of lower-voltage TEM performance using 3D Fourier transform of through-focus series

作者：Kimoto Koji^*; Kurashima Keiji; Nagai Takuro; Ohwada Megumi; Ishizuka Kazuo

来源：Ultramicroscopy, 2012, 121: 31-37.

DOI：10.1016/j.ultramic.2012.06.012

• High-resolution transmission electron microscopy
• Low acceleration voltage
• Spherical aberration corrector
• Information limit
• Young fringe
• Monochromator

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.

• 出版日期2012-10