Field Emission-Scanning Electron Microscopy

In FESEM, a field emission gun (FEG) is used as the electron source, which employs the principle of field emission to generate electrons. The FEG consists of a sharp, tungsten needle that acts as the cathode. When a strong electric field is applied, electrons are extracted from the cathode and accelerated towards the anode. This process occurs under ultra-high vacuum conditions to prevent the scattering of electrons by gas molecules.

The high-energy electrons emitted from the FEG are focused and directed onto the sample surface using electromagnetic lenses and scanning coils. As the electron beam interacts with the sample, various signals are generated, including secondary electrons, backscattered electrons, and X-rays. These signals are detected and processed to create high-resolution images and provide analytical information about the sample’s composition and structure.

• Characterization of material surfaces, fracture analysis, grain boundary studies, phase identification
• Analysis of microstructures and defects in metals, ceramics, and composites
• Study of surface modifications and coatings

• Imaging and analysis of nanostructures, nanoparticles, nanotubes, and nanomaterials
• Characterization of self-assembled nanostructures and nanodevices
• Investigation of nanomaterial properties and surface interactions

• Failure analysis and defect characterization of integrated circuits
• Cross-sectional analysis of semiconductor devices and interconnects
• Imaging and analysis of thin films and device structures

• Characterization of energy materials, such as battery components, fuel cell electrodes, and photovoltaic devices
• Analysis of electrode surfaces and electrode-electrolyte interfaces
• Investigation of energy storage and conversion processes

• Analysis of biomaterials, implants, tissue engineering scaffolds, and biological samples
• Characterization of surface properties and biocompatibility
• Imaging of cells, proteins, and biological structures

• Study of metal microstructures, grain boundaries, and phase analysis
• Corrosion analysis and failure investigation of metallic components
• Characterization of surface treatments and coatings on metals

• Analysis of environmental samples, particulate matter, and contaminants
• Characterization of airborne particles and their sources
• Investigation of environmental remediation processes

• Examination of trace evidence, such as gunshot residue and explosive particles
• Analysis of document inks, toners, and counterfeit materials
• Characterization of fibers, hair, and other forensic samples

• High resolution: FESEM provides high spatial resolution, enabling the visualization of features at the nanometer scale.
• Analytical capabilities: FESEM can be coupled with various analytical techniques, such as energy-dispersive X-ray spectroscopy (EDS) and electron backscatter diffraction (EBSD), for compositional and structural analysis.
• Large depth of field: FESEM offers a larger depth of field compared to conventional SEMs, allowing the imaging of rough or uneven surfaces.
• Versatility: FESEM can analyze a wide range of materials, including metals, ceramics, polymers, and biological samples.

• Sample size: Typically, small samples (a few millimeters to centimeters in size) are suitable for FESEM analysis.
• Sample compatibility: Samples should be compatible with the high vacuum environment inside the FESEM chamber.
• Solid sample: Maximum 15 cm².
• Powders: 10 mg.
• Sample should be high vacuum compatible (~1 x 10^-5 Torr).
• Ag or Au sputtering Will be carried out for non-conducting samples.