Aberration-corrected transmission electron microscopy allows us to image the structure of matter at genuine atomic resolution. A prominent role for the imaging of crystalline samples is played by the ...negative spherical aberration imaging (NCSI) technique. The physical background of this technique is reviewed. The especially high contrast observed under these conditions owes its origin to an enhancing combination of amplitude contrast due to electron diffraction channelling and phase contrast. A number of examples of the application of NCSI are reviewed in order to illustrate the applicability and the state-of-the-art of this technique.
Transmission electron microscopy is an indispensable tool in modern materials science. It enables the structure of materials to be studied with high spatial resolution, and thus makes a decisive ...contribution to the fact that it is now possible to understand the microstructure-related physical and chemical characteristics and to correlate these with the macroscopic materials properties. It was tantamount to a paradigm shift when electron microscopy reached atomic resolution in the late 1990s due to the invention of aberration-corrected electron optics. It is now generally accepted practice to perform picometer-scale measurements and chemical analyses with reference to single atomic units. This review has three objectives. Microscopy in atomic dimensions is applied quantum physics. The consequences of this for practical work and for the understanding and application of the results shall be worked out. Typical applications in materials science will be used to show what can be done with this kind of microscopy and where its limitations lie. In the absence of relevant monographs, the aim is to provide an introduction to this new type of electron microscopy and to enable the reader to access the literature in which special issues are addressed. The paper begins with a brief presentation of the principles of optical aberration correction. It then discusses the fundamentals of atomic imaging and covers typical examples of practical applications to problems in modern materials science. It is emphasized that in atomic-resolution electron microscopy the quantitative interpretation of the images must always be based on the solution of the quantum physical and optical problem on a computer.
FEI Tecnai G2 F20 Luysberg, Martina; Heggen, Marc; Tillmann, Karsten
Journal of large-scale research facilities,
06/2016, Volume:
2
Journal Article
Open access
The FEI Titan Tecnai G2 F20 is a versatile transmission electron microscope which is equipped with a Gatan Tridiem 863P post column image filter (GIF) and a high angle energy dispersive X-ray (EDX) ...detector. This set up allows for a variety of experiments such as conventional imaging and diffraction, recording of bright- and dark-field scanning transmission electron microscopy (STEM) images, or acquiring elemental maps extracted from energy electron loss spectra (EELS) or EDX signals.
The FEI Helios NanoLab 460F1 is a highly advanced dual beam FIB-SEM platform for imaging and analytical measurements, transmission electron microscopy (TEM) sample and atom probe (AP) needle ...preparation, process development and process control. For these purposes, the FEI Helios NanoLab 460F1 combines an ElstarTM UC technology electron column for high-resolution and high material contrast imaging with the high-performance TomahawkTM ion column for fast and precise sample preparation. The FEI Helios NanoLab 460F1 is additionally equipped with the MultiChemTM gas delivery system, an EasyLiftTM nanomanipulator, a cooling trap, an inert gas transfer (IGT) holder loadlock, a quick loader, a FlipStage 3TM, an EDX-System and an STEM III detector. This instrument is one of the few dual beam systems which combine an IGT holder loadlock with a FlipStage 3+TM EasyLiftTM nanomanipulator. Typical examples of use and technical specifications for the instrument are given below.
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