Börrnert Felix, Uhlemann Stephan, Müller Heiko, Gerheim Volker, Haider Maximilian
CEOS GmbH, Englerstraße 28, 69126 Heidelberg, Germany.
CEOS GmbH, Englerstraße 28, 69126 Heidelberg, Germany.
Ultramicroscopy. 2023 Nov;253:113805. doi: 10.1016/j.ultramic.2023.113805. Epub 2023 Jul 10.
An electron monochromator design is presented as an instrumental development for electron energy loss spectroscopy (EELS) and imaging in (scanning) transmission electron microscopy ((S)TEM). The main purpose of this development is enhancing the energy resolving power in spectroscopy and filtering. In addition, it helps reducing the effect of the objective lens' chromatic aberration C in imaging and therefore, enhancing the spatial resolving power of electron microscopes. General estimates for the performance of a monochromator in energy distribution and the resulting usable beam currents are given. The special monochromator design presented is a ground-potential monochromator based on magnetic sector fields. The monochromator generates a spatially and angular un-dispersed spot and has no mechanically actuated parts in the filter sections. The optics can be operated at electron acceleration voltages from 30kV to 300kV and shows an energy resolving power of better than 2⋅10 relative to the primary electron energy. The actual device is designed to be retro-fittable to microscopes from various manufacturers.
本文介绍了一种电子单色仪设计，它是用于电子能量损失谱（EELS）以及（扫描）透射电子显微镜（(S)TEM）成像的一种仪器开发。该开发的主要目的是提高光谱学中的能量分辨能力以及滤波能力。此外，它有助于降低成像中物镜色差C的影响，从而提高电子显微镜的空间分辨能力。文中给出了单色仪在能量分布方面的性能以及由此产生的可用束流的一般估计。所介绍的特殊单色仪设计是一种基于磁扇形场的地电位单色仪。该单色仪产生一个空间和角度上未色散的光斑，并且在滤波部分没有机械驱动部件。该光学系统可在30kV至300kV的电子加速电压下运行，相对于一次电子能量，其能量分辨能力优于2⋅10 。实际装置设计为可对各种制造商生产的显微镜进行改装。
