SEM
Scanning Electron Microscopy
Characterisation Installation 4
In a SEM, a beam is scanned over the sample surface in a raster pattern while a signal from secondary electrons (SE) or Back-scattered electrons (BSE) is recorded by specific electron detectors. The electron beam, which typically has an energy ranging from a few hundred eV up to 40 keV, is focused to a spot of about 0.4 nm to 5 nm in diameter. Latest generation SEMs indeed can achieve a resolution of 0.4 nm at 30 kV and 0.9 nm at 1 kV.
Beyond the ability to image a comparatively large area of the specimen, SEM can be equipped with a variety of analytical techniques for measuring the composition, crystallographic phase distribution and local texture of the specimen. Chemical composition analysis can be performed by Energy Dispersive X-ray Spectroscopy (EDS) which relies on the generation of an X-ray spectrum from the entire scan area of the SEM. An EDS detector mounted in the SEM chamber collects and separates the characteristic X-rays of different elements into an energy spectrum and EDS system software is used to analyse the energy spectrum in order to determine the abundance of specific elements. EDS can be used to find the chemical composition of materials down to a spot size of a few microns and to create element composition maps over a much broader raster area.
An SEM complemented with a (FIB) focused ion beam permits in addition an in-depth analysis by creating a cross-section cut that is subsequently analysed using the electron beam and the SEM/EDS detectors (slice&view). In a similar way, a 3D tomography can be generated by an iterative ion beam milling and electron beam imaging. Furthermore, the ion beam permits to cut a thin lamella out of a sample surface that could be taken out by a micro-manipulator and analysed with the electron beam in transmission using a so called STEM (scanning transmission electron microscope) detector.
WARNING: Access to CNRS temporarily not available, but the technique is available at the other sites
SEM – FEI Quanta 650 FEG ESEM
SEM – FEI Magellan 400L XHRSEM
SEM - LEO 1560
Hitachi SU8010
JEOL JSM-6700F SEM
SEM – Zeiss Merlin
Zeiss Supra 55 VP @ Laboratory for Micro- and Nanotechnology
Hitachi H5500 High resolution SEM
SEM @ DESY NanoLab
Imaging of surfaces in reflection mode, in scanning mode and scanning transmission microscopy (STEM), elemental analysis by EDX (point and line analysis, mappings)
SE Everhart-Thornley detector (ETD)
Low vacuum BE detector
High resolution through-lens detector tunable for SE and BE mode
High resolution STEM detector for analysis of membranes and thin films in transmission
X-Max 150 EDS silicon drift detector for elemental analysis, energy resolution 127 eV @ MnKα (Oxford)
IR-CCD camera to track the sample position
SEM-EDX
High efficiency in-lens detector
Everhart-Thornley Secondary Electron Detector
Cap mounted AsB detector
CCD-camera with IR illumination
FIB-SEM
FE-SEM LEO 1530 + Elphy Plus (N6)
QUANTA FEI 200 FEG-ESEM
Imaging, size, morphology and microstructure; high-profile nanostructural characterization; non-destructive analytical techniques (imaging and microanalysis); nanometer level inspection of materials, lithography and nanolithography
EDT - Detector Everhart Thornley: high-vacuum mode, EDX mode, RAITH mode
BSED - Solid State Backscatter Detector: high-vacuum mode, low-vacuum mode, EDX mode, RAITH mode
CCD - Infrared inspection camera: high-vacuum mode, low-vacuum mode, Environmental mode, RAITH mode
LFD - Large Field detector: low-vacuum mode, EDX mode
GSED - Gaseous Detector: Environmental mode
High-vacuum: 1.2nm at 30kV (SE), 2.5nm at 30kV (BSE), 3.0nm at 1kV (SE)
Low-vacuum: 1.5nm at 30kV (SE), 2.5nm at 30kV (BSE), 3.0nm at 3kV (SE)
Environmental mode: 1.5nm at 30kV (SE)
EDX mode: energy resolution of 132 eV, chemical analysis with a high lateral resolution (point analyses and elemental mapping)
Conducting materials (High-vacuum)
Uncoated non-conducting materials (Low-vacuum, Environmental mode)
Complex multi-component nanostructured materials (EDX)
