Covalent

Focused Ion Beam SEM (FIB-SEM) Analysis

FIB-SEM combines ion milling and electron imaging for site-specific cross-sections, TEM lamella preparation, and 3D nanoscale imaging.

FIB-SEM analysis combines a focused ion beam, which mills material away with nanometer precision, and a scanning electron microscope, which images the exposed surface. It is used to cut site-specific cross-sections, prepare TEM lamellae, and build 3D reconstructions of subsurface features in devices, coatings, batteries, and other materials.

What Is Focused Ion Beam Scanning Electron Microscopy?

Focused ion beam scanning electron microscopy (FIB-SEM) uses two beams in one instrument. The ion beam removes material to expose subsurface features, and the electron beam images them at high resolution. Combined with EDS, it reveals the chemical composition of specific regions. FIB-SEM works on metals, ceramics, polymers, and semiconductors, with lateral milling resolution of about 5–10 nm using a Ga⁺ ion beam, and it reaches from nanometers to tens of microns below the surface.

Composition

Combined with EDS, maps elemental composition alongside structural detail.

Versatility

Compatible with metals, ceramics, polymers, and semiconductors, accommodating diverse research and industrial needs.

Resolution

Captures nanoscale detail of subsurface features for precise structural analysis.

Why Use FIB-SEM?

FIB-SEM is the go-to tool for precise, site-specific analysis of micron- and submicron-scale features in devices, thin films, composites, and other materials. It exposes the exact location you need, extracts and thins lamellae to electron transparency (about 100 nm) for transmission electron microscopy (TEM), and builds 3D reconstructions at nanometer resolution. Imaging and milling happen in one system, with correlative SEM, EDS, and EBSD on the same cut face.

Precision

Targets specific regions of interest with nanometer-level accuracy.

Versatility

Supports metals, semiconductors, ceramics, polymers, and bio-samples across multiple imaging modes.

3D Insight

Enables FIB-SEM tomography for volumetric understanding of nanoscale structure.

How FIB-SEM Works

A FIB-SEM, also called a dual-beam system, positions an electron column and an ion column at an angle so both beams meet at the same point on the sample. A typical analysis follows four steps:

  1. Locate the feature. The SEM images the surface to find the defect, layer, or region of interest.
  2. Protect the surface. A thin platinum layer is deposited over the site to preserve the top surface during milling.
  3. Mill. The ion beam removes material to cut a trench, a cross-section, or a lamella, usually with the stage tilted to 52°.
  4. Image and analyze. The SEM images the exposed face, with EDS for composition and EBSD for crystal orientation.

Milling can range from nanometers to tens of microns. Gallium and plasma ion sources behave differently; read Gallium vs. Plasma FIB: What's Actually Happening Inside the Column for the trade-offs.

FIB-SEM Services

Three new sections, each targeting a search people make for a specific FIB service.

FIB Cross-Sectioning

FIB cross-sectioning exposes a precise vertical face through a defect, layer stack, solder joint, or interface, without the smearing or delamination that mechanical polishing can cause. A protective platinum cap preserves the top surface, and the cut face is imaged with SEM and mapped with EDS. Cross-sections can reach up to about 100 µm wide and tens of microns deep.

What you get: SE and BSE images of the cross-section, layer thickness measurements, EDS maps, and EBSD on request.

TEM Lamella Preparation

Covalent prepares site-specific TEM lamellae from wafers, devices, and bulk materials, thinned to electron transparency (under about 100 nm). Automated AutoTEM software delivers fast, repeatable lamella preparation, and low-kV final polishing reduces surface damage. Lamellae go straight to our TEM and STEM for imaging, EDS, and EELS. Learn more in our webinar Preparing Better TEM Samples Faster.

What you get: a site-specific lamella, preparation images showing its location, and optional TEM or STEM analysis.

FIB-SEM Tomography (Slice and View)

FIB-SEM tomography mills away thin slices and images each new face to build a 3D reconstruction of the volume. It reveals the size, shape, connectivity, and distribution of pores, particles, cracks, and phases that a single cross-section can miss, for example in battery electrodes, catalysts, and porous films. Reconstructions use Thermo Fisher Slice and View with Avizo software.

What you get: the image stack, 3D renderings, and quantified volume fractions and pore or particle statistics.

Equipment Used for FIB-SEM

ThermoFisher Scientific Helios 5 UC Dual Beam

  • Electron beam resolution:
    • At optimum WD:
      • 0.6 nm at 30 kV STEM.
      • 0.7 nm at 1 kV.
      • 1.0 nm at 500 V (ICD).
    • At coincident point:
      • 0.6 nm at 15 kV.
      • 1.2 nm at 1 kV.
  • UC+ monochromator.
  • Ion Optics: Down to 500kV for final polishing on TEM lamella.
  • Automated TEM Prep for fast/repeatable throughput: Thermo Scientific™ AutoTEM™ Software for automated STEM sample preparation.
  • Sample:
    • Max sample weight: 500 g (including sample holder).
    • Max sample size: 150 mm with full rotation (larger samples possible with limited rotation).
Specifications

ThermoFisher Scientific Helios 6 HD Dual Beam

  • New FIB column with automated source and column alignments provides increased stability and low-kV milling capabilities.
  • New digital scanning and patterning engine allows for simultaneous SEM imaging and FIB milling which enables more precise end-pointing and higher productivity.
  • AutoTEM 6 Software-targeted application designed to deliver the most out of the new Helios 6 HD FIB-SEM’s hardware platform. This AI-enabled software automatically aligns all grid/finger locations, offering enhanced grid management capabilities and a decrease in set-up time.
  • Longer interval between EasyLift NanoManipulator needle exchanges and streamlined replacement, leading to increased system availability and consistent results.
Specifications

Key Differentiators

Strengths

  • Fine details in surface topography, such as texture, roughness, and microstructure, are easy to see.
  • Able to view the shape, size, and arrangement of particles, fibers, pores, grains, etc., due to the high magnification range and depth of field.
  • Can provide precise 2D measurements of lengths, diameters, feature sizes, such as layer thicknesses, pore or particle sizes.
  • Qualitative or semi-quantitative chemical composition of visible features.

Limitations

  • SEM needs vacuum-stable, conductive samples.
  • Magnetic materials can be analyzed with caution, using field-free observation modes. Avoid ultra-high resolution mode.
  • FIB milling is incompatible with low vacuum modes.
  • Spatial resolution is worse than TEM and degrades with high voltage/light elements.

Example Outputs

FIB-SEM cross-section of a pixel array, showing underlying nm-scale device features.

Sample Requirements

  • Solid phase.
  • Must be vacuum stable.
  • Maximum Sample Height: 55 mm.
  • Maximum Sample Weight: 500 g (including sample-holder).
  • Maximum Lateral Dimension: 150 mm (larger samples enabled with reduced rotation).

FIB-SEM Applications by Industry

Semiconductor

FIB-SEM is often used for failure analysis and process monitoring on semiconductor samples. The FIB can be used to make cross sections on the nanoscale while SEM is used in combination with EDS to image and chemically characterize the cross section.

Materials

FIB cross-section of copper foils for EBSD analysis of the cross-section for grain size and crystallographic orientation analysis.

Battery Technology

Recurring Covalent client requires routine sample analysis of a thin film stack. Covalent has successfully optimized the FIB-SEM-EDS procedures for these samples to minimize turnaround time and deliver quality data to the client.

TEM Lamella Prep

For multiple industries, including semiconductor fabrication, semiconductor devices, data storage, IC packaging, battery, optoelectronics, coatings/thin films, life sciences, and medical devices.

Techniques That Complement FIB-SEM

Secondary Ion Mass Spectrometry
An elemental analysis technique with ultra-sensitive chemical and isotropic analysis, used to prepare flat or site-specific surface for high-resolution SIMS.
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Measures 3D nanoscale surface topography and mechanical properties, useful for nanoscale surface characterization.
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A surface-sensitive elemental analysis technique with high spatial resolution, ideal for interface and failure analysis.
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Detects molecular bonds and chemical structures, and is ideal for contamination and surface residue analysis.
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Provides atomic-scale resolution of internal features.
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Provides atomic-resolution imaging and crystallographic detail.
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Provides elemental and chemical state information of the top few nanometers of the surface, ideal for surface chemistry and thin films.
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FIB-SEM Testing Services at Covalent

Our clients trust Covalent for SEM analysis results that exceed their expectations. We provide industry-leading, high-resolution scanning electron microscopy capabilities that offer superior data essential for understanding and optimizing the quality of your materials.

Frequently Asked Questions

What is FIB-SEM used for?

FIB-SEM (Focused Ion Beam – Scanning Electron Microscopy) is a powerful dual-beam instrument for microscale and nanoscale imaging, material modification, and analytical characterization. It combines the capabilities of a scanning electron microscope (SEM) for high-resolution imaging with a focused ion beam (FIB) for site-specific milling, deposition, and sample preparation.

How do you interpret FIB-SEM images?

Interpretation of SEM images of FIB cross sections relies on understanding how different contrast mechanisms relate to sample features, beam settings, and detector types. For topographic contrast using secondary electrons, bright areas are the sample’s regions facing the detector, whereas dark areas are recessed or shadowed. This allows one to identify cracks, voids, fibers, surface roughness, and 3D surface shapes. For compositional contrast using backscattered electrons, bright areas are higher atomic number elements, and darker areas are lower atomic number elements (gold vs carbon). This type of contrast allows one to identify inclusions, multi-phase materials, contamination, and coating layers. Be sure to pay attention to the scale bar when comparing the relative sizes of features in the SEM image of a FIB cross-section. When measuring the length of a vertical feature in a FIB cross-section (i.e., thin film thickness), it is essential to know the stage tilt at which the image was collected (typically 52 degrees). When using the horizontal scale bar when measuring the thin film thickness, one must multiply that value by the cosine of the complementary angle (i.e., cosine(38 degrees)) to calculate the film thickness.

What level of resolution can FIB-SEM achieve?

Under high-resolution conditions with a Ga⁺ focused ion beam (FIB), the best lateral resolution is ~5–10 nm. For imaging, a field emission scanning electron microscope (SEM) can reach sub-nanometer spatial resolution in ultra-high resolution mode.

Which industries commonly use FIB-SEM for failure analysis or microfabrication?

FIB-SEM is widely used in semiconductors, microelectronics, batteries, and the energy industry for precise cross-sectioning, defect analysis, and microfabrication.

What elemental sensitivity can be achieved with EDS in FIB-SEM?

Energy Dispersive X-ray Spectroscopy (EDS) in FIB-SEM is semi-quantitative and accurate within 0.1 weight percent. However, EDS cannot detect H, He, or Li with most detectors, and sensitivity to light elements (B, C, N, O) is reduced due to low X-ray yields and overlaps.

How is beam-induced damage minimized during FIB-SEM analysis?

Beam damage can be minimized by lowering beam energy and current to reduce the dose. This approach applies to both the electron beam and the focused ion beam, making it essential for analyzing sensitive samples.

What are the advantages of integrating EBSD or EDS with FIB-SEM?

Integrating EDS provides localized chemical composition analysis of cross-sectioned regions, enabling material identification of subsurface features. EBSD (Electron Backscatter Diffraction), under specialized conditions, can be combined with FIB-SEM for localized crystallographic mapping, revealing grain boundaries, phase orientation, and texture.

When should FIB-SEM be used instead of traditional SEM or TEM?

FIB-SEM is necessary when subsurface features must be accessed. Traditional SEM is surface-limited, while FIB enables precise cross-sections. FIB-SEM is also used to prepare TEM lamellae. TEM areas are typically 5–10 µm wide and only a few microns deep, while FIB-SEM cross-sections can reach up to 100 µm wide and tens of microns deep.

What are the sample preparation requirements for FIB-SEM analysis?

Metals: Minimal preparation needed due to high conductivity. Ceramics/Polymers: Often require thin conductive coatings and grounding layers to avoid charging. Semiconductors: Can often be analyzed at low voltages without coating, but coatings are usually required when devices or passivation layers are present. Good sample conductivity is critical. Non-conductive or unstable samples may drift or accumulate charge, reducing cross-sectioning accuracy.

What are the limitations of FIB-SEM for material analysis?

Vacuum requirement: Samples must be vacuum-stable; liquids or volatile materials are not compatible. Resolution: Lower than TEM; worsens with beam broadening at high voltages or in low-Z materials. EDS sensitivity: Cannot measure H, He, or Li; reduced accuracy for light elements. Sample sensitivity: Biological and organic materials may degrade under beam exposure.