Scanning Electron Microscopy (SEM)
Scanning Electron Microscopy (SEM) can be used to image sample surface topography, morphology, and texture, and to analyse element composition across a diverse range of samples. SEM is widely utilised across the materials sciences, bio-and medical sciences, and environmental and geo-sciences, enabling imaging and analysis of, for example, cellular materials, advanced nanomaterials, and mineral specimens. Different SEM configurations can accommodate a variety of sample types, including non-conductive materials using low vacuum SEM and hydrated samples through cryo-SEM.
Our services
Training and Access
We provide introductory and advanced training for students and researchers wanting to access the electron microscopy facilities for their research. Our training programs are tailored to the needs of the researcher and use a blended learning approach combining self-paced online and face-to-face components.
Expert Advice and Service
The electron microscopy team are available to provide expert advice and support for all aspects of your project including: project design, sample preparation, data acquisition, data processing, and publishing your results.
Research Collaboration
Our expert staff have significant research experience and are actively engaged in research collaborations with university researchers and industry partners in the physical sciences, biosciences, and geosciences. They participate as Chief and Partner Investigators on research grants and as supervisory team members for research students.
Samples
Samples for SEM can range from centimetre to nanometre scales but must be stable within the vacuum environment inside the microscope. Our facility is equipped with an array of sample preparation equipment designed to prepare suitable samples from both physical and biological samples.
Our techniques
Surface structural imaging
Surface structural imaging in SEM provides high-resolution information on the morphology and structure of sample surfaces, ranging from micro- to nano-metre scales. In materials science and nanotechnology, SEM can reveal particle size and shape, grain size, surface roughness, and coating integrity, essential for evaluating material properties. In the geosciences, SEM can be used to examine mineral structures, shapes, and sizes, while in biosciences it is useful for imaging micro-organisms to tissue structures, interfaces, and cell adhesion and interactions.
Compositional imaging
Compositional imaging in SEM using backscattered electron (BSE) imaging and energy-dispersive x-ray spectroscopy (EDS) generates images related to the elemental composition and phase distribution within a sample. BSE imaging differentiates materials with varying atomic numbers, highlighting general compositional differences, while EDS can provide elemental maps showing the distribution and/or concentration of individual elements.
Element analysis
Elemental analysis in SEM can be performed using energy-dispersive x-ray spectroscopy (EDS) or wavelength-dispersive spectroscopy (WDS). EDS and WDS can both be used to identify, map, and quantify a wide range of elements and can be applied to samples across the materials, geo-, and bio-sciences. WDS offers enhanced sensitivity and accuracy for detecting minor and trace elements in complex materials, particularly minerals.
3D volume imaging
Three-dimensional (3D) volume imaging in SEM can be achieved by utilising a focused ion beam (FIB) to mill layers of the sample while capturing sequential SEM images. The resulting image stack can be reconstructed into a volume that reveals the sample structure in 3D at the nanoscale and is commonly used to investigate the 3D structure of materials (e.g. alloys, minerals, semi-conductor devices), and biological systems (e.g. cell ultrastructure, interactions between cell/sub-cellular components).
Nanofabrication
Nanofabrication in FIB-SEM utilises a focused ion beam to precisely modify and shape materials at the nanoscale. This technique enables highly controlled material removal (milling) or deposition, allowing for the creation of nanostructures with custom-designed patterns and features. FIB-SEM nanofabrication is extensively used in semiconductor device development, nanotechnology, and materials science, enabling the fabrication of nanoscale structures such as nanoscale circuits and sensors. The integration of SEM imaging allows real-time monitoring of the nanofabrication process, ensuring exceptional precision and accuracy in the production of complex designs.
CryoSEM
CryoSEM involves rapid freezing of a sample followed by surface structural imaging and/or element analysis (EDS) whilst the sample is still frozen. This allows imaging and analysis of a sample within the SEM vacuum without the need for chemical processing or drying. CryoSEM is particularly suited to imaging hydrated materials, such as liquids and gels, foods, cells and tissues, and composite solutions. CryoSEM-EDS is essential for preserving and immobilising diffusible elements in cell and tissue analyses.
Our instruments
- FEI Verios SEM
- FEI Helios FIB-SEM
- ZEISS Supra SEM
- TESCAN VEGA SEM
- JEOL Neoscope SEM
- JEOL CryoSEM
- JEOL 8530F microprobe
- JEOL 8530F+ microprobe
Our team
Martin Saunders
Physical Sciences Electron Microscopy Platform Leader, Centre for Microscopy, Characterisation and Analysis
Peta Clode
Biosciences Electron Microscopy Platform Leader, Centre for Microscopy, Characterisation and Analysis
Alexandra Suvorova
Physical Sciences Electron Microscopy Specialist, Centre for Microscopy, Characterisation and Analysis
Malcolm Roberts
Geosciences Scanning Electron Microscopy and Microprobe Specialist, Centre for Microscopy, Characterisation and Analysis
Minakshi Das
Biosciences Electron Microscopy Specialist, Centre for Microscopy, Characterisation and Analysis