Electron Microscopy Center

Empa's Electron Microscopy Center located in Dübendorf offers electron microscopy services to internal and external R&D partners. The center conducts forefront research in the development and application of new electron microscopy techniques in materials science and acts as a consulting unit for electron microscopy in materials science. The staff of the center carries out research tasks on-demand, offers training and provides hands-on support for practical applications.

Pt_CeO.gif
In-situ time series of structural dynamics in the Pt/CeO2 system recorded at 600°C (more details).

The center operates transmission electron microscopes, scanning electron microscopes and facilities for specimen preparation. Besides convention electron optical imaging (TEM & SEM), the instrumentation can be used for environmental and low-voltage SEM imaging, electron diffraction, atomic-resolution imaging by HRTEM and (aberration-corrected) STEM (Z-contrast imaging), and for analytics, covering high-efficiency EDX spectroscopy (TEM & SEM), electron backscatter diffraction (EBSD), electron energy-loss spectroscopy (EELS) and energy-filtered imaging (EF-TEM). A list of the available instrumentation can be found here.

Our expertise comprises various imaging and in particular atomic-resolution microscopy techniques in the broad-beam and the scanning transmission modes, core-loss and low-loss electron energy-loss spectroscopy as well as electron tomography, in-line and off-axis electron holography for mapping electrostatic and magnetic fields at various length scales as well as differential phase contrast (DPC) STEM, which provides an alternative method to access electrostatic or magnetic information about the specimen. Furthermore, some of our research activities focus on in-situ measurements in (S)TEM using MEMS-based liquid-cell and biasing/heating specimen stages. The experimental work is complemented by image simulations and by first-principles theoretical approaches to calculate electron energy-loss spectra of model structures. For the different simulations, software packages and workstations are available.

More information about our research activities can be found on our research website.

EDS+of+LiF.jpg
EDS spectrum of a LiF sample acquired on the Zeiss GeminiSEM 460. Due to its high sensitivity to light elements, the Ultim® Extreme EDS detector allows for detecting Li in LiF.

Members of the electron microscopy group work on various research projects involving functional oxides, catalytic metal clusters, as well as tomography and in-situ methods.

Our core expertises are:

  • Atomic-resolution imaging in STEM and TEM
  • Core- and low-loss EELS
  • Elemental mapping by EDS, EELS and EF-TEM
  • Electron tomography
  • DPC STEM
  • In-line and off-axis electron holography
  • In situ microscopy: liquid-phase, electrical biasing and heating
  • Advanced data analysis methods and simulations
EBSD+map.jpg
EBSD map of a martensitic steel sample acquired on the Zeiss GeminiSEM 460 (Oxford EBSD detector Symmetry S2). The map reveals information about the grain boundaries and the grains' orientations of the steel sample.
EDX+STO+LAO.jpg
Atomic-resolution STEM/EDX elemental maps of a multilayered system consisting of SrTiO3 and LaAlO3 acquired on the FEI Titan Themis.

News
  • November 2024: New PhD position available in the EMC: We are looking for a doctoral student in the field of transmission electron microscopy of 2D van der Waals layered ferroelectrics as of February 2024 or upon agreement.
  • July 2024: Yifan Zhao successfully defended her master thesis at UZH on 4 July 2024: Design and Microstructural Characterization of Free-standing Ferroelectric Membranes.
    Congratulations!

  

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Aberration-Corrected Imaging in Transmission Electron Microscopy – An Introduction

2nd edition (2015): available here