FAQs & Glossaries
Author: Judith Beer
Published: 05 Oct 2026 · Last updated: 06 Oct 2026
Electron Backscatter Diffraction (EBSD) provides crystallographic and microstructural information from crystalline materials in the scanning electron microscope. This FAQ answers common questions about EBSD principles, Kikuchi patterns, sample preparation, measurement conditions, resolution and related diffraction techniques.
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EBSD orientation map revealing the mineral architecture of the stony coral Montastraea cavernosa.
Electron Backscatter Diffraction (EBSD) is a Scanning Electron Microscope (SEM) technique used to determine the crystallographic structure, orientation, and phase of materials. EBSD analyses Kikuchi diffraction patterns, which are generated when an electron beam interacts with a crystalline sample. The analysis provides detailed maps of grain orientation, grain boundaries, texture, and phase distribution. It is widely used across research and advanced manufacturing to understand material microstructure-property relationships.
Learn more about EBSD on ebsd.com
In EBSD, an electron beam is directed at a crystalline sample tilted by approximately 70° inside the SEM. The interaction between the electron beam and the sample generates backscattered electrons that form a Kikuchi diffraction pattern. This pattern is captured by an EBSD detector and indexed by processing software to determine the crystal orientation and phase at that measurement point. By scanning the electron beam across the sample surface and collecting a diffraction pattern at each position, EBSD generates crystal and phase maps for the region of interest.
EBSD is used to characterise crystallographic orientation, grain size, texture, strain, and phase distribution in crystalline materials. It provides valuable crystallographic and microstructural information that helps researchers and manufacturers understand how materials form and behave. EBSD is applied in metallurgy, geology, semiconductors, additive manufacturing, and failure analysis, and is widely adopted for R&D and quality control in academic and industrial environments.
EBSD can be used to analyse crystalline solids, including metals, ceramics, minerals, and semiconductors. Non-crystalline materials such as glass do not produce Kikuchi patterns and therefore cannot be analysed using EBSD. Material characteristics such as atomic number, crystal structure, and sample quality influence EBSD signal strength and the SEM operating conditions required for reliable results.
Kikuchi patterns are diffraction patterns that form when backscattered electrons interact with crystal lattice planes inside a material. As the electrons satisfy Bragg’s condition during scattering, they form characteristic diffraction bands that correspond to specific crystallographic planes. These patterns, often referred to as Electron Backscatter Patterns (EBSPs), are projected onto the EBSD detector and captured for analysis. The geometry of these bands reflects the crystal symmetry and orientation, which the EBSD software can reconstruct.
Read more about Kikuchi pattern formation here.
EBSD software uses Kikuchi patterns and the known acquisition geometry of the measurement to determine the crystal orientation and phase of a material. To do this, it identifies diffraction bands within the measured Electron Backscatter Patterns (EBSPs) and compares their angular relationship with crystallographic reference data stored in a database. This approach is commonly known as Hough-based indexing.
More advanced indexing methods can also use diffraction band intensities and compare the entire pattern with reference patterns to improve accuracy and robustness.
Learn more about EBSD pattern indexing here.
The quality of an EBSD pattern depends on several factors, including sample preparation, material properties, acquisition settings, and SEM operating conditions. Higher accelerating voltages and a clean, flat, and damage-free sample surface generally improve diffraction band contrast. Detector sensitivity and noise performance also play an important role in capturing high-quality diffraction patterns suitable for reliable indexing.
EBSD grain orientation map of nickel, revealing crystallographic orientation variations across the microstructure.
A high sample tilt increases the number of backscattered electrons that reach the EBSD detector. Typical EBSD experiments are performed with the sample tilted between 65° and 75° relative to the incident electron path. A higher tilt angle increases backscattered electron yield and improves diffraction pattern quality. However, increasing the tilt also reduces spatial resolution. The selected tilt angle is therefore a practical balance between diffraction signal strength and spatial resolution.
To obtain high-quality EBSD patterns and ensure reliable indexing, a clean, flat, and deformation-free sample surface is critical. Best practice for EBSD sample preparation includes careful cutting, mounting, grinding, and mechanical polishing to remove deformation layers. Final vibratory, electrolytic, or ion polishing can further refine the surface. Poor sample preparation reduces the quality of EBSD results regardless of detector capabilities.
Learn more about sample preparation for EBSD on ebsd.com.
Chemical etching is not inherently required for EBSD but is sometimes used in metallurgy to remove residual deformation or reveal phases during preparation. The essential requirement is a flat, damage-free surface that is often achieved by mechanical polishing and final ion-beam finishing rather than etching.
EBSD can technically acquire data from slightly uneven surfaces, but significant roughness introduces geometric distortions that degrade Kikuchi pattern clarity and reduce indexing accuracy. Local height variations cause inconsistent band projection across the field of view, making the results less reliable. For quantitative mapping and high-resolution analysis, a uniformly polished, flat surface remains essential.
EBSD is generally regarded as non-destructive because the electron interaction is confined to a shallow region at the sample surface. However, the technique requires intensive sample preparation, including polishing steps that modify the surface layer but do not affect the bulk material. Some applications may require Focussed Ion Beam (FIB) preparation or sectioning for site-specific or subsurface analysis, but these interventions remain highly localised.
EBSD Steel phase map.
The interaction volume in EBSD refers to the near-surface region of the sample where the electron beam generates backscattered electrons that contribute to the measured diffraction patterns. Its depth is typically limited to a few hundred nanometres or less and depends on the electron beam’s accelerating voltage, material density, and the atomic number of the elements present.
Spatial resolution refers to the smallest feature size that can be resolved in an EBSD dataset. The physical spatial resolution of EBSD is governed by the size of the interaction volume, which depends on the accelerating voltage and diameter of the electron beam, sample tilt and material density. For a given sample, reducing the accelerating voltage, probe current or sample tilt can improve spatial resolution by reducing the interaction volume.
However, the effective spatial resolution observed in a dataset does not depend solely on the interaction volume. It is also influenced by the software’s ability to analyse overlapping patterns, pattern quality and acquisition step size. This means that the effective spatial resolution of an EBSD map is typically better than the separation of adjacent interaction volumes alone.
Angular resolution describes the precision of crystallographic orientation measurements. It depends on pattern quality, pattern pixel resolution, and EBSD indexing algorithms. High-quality patterns and advanced indexing methods improve angular precision. This is critical for analysing low-angle boundaries, misorientation and strain, and for distinguishing orientations that could otherwise cause pseudosymmetry errors.
Detector resolution, expressed as the number of pixels in an electron backscatter pattern, influences the accuracy and robustness of EBSD pattern indexing. Higher pixel resolution enables improved band detection and orientation measurements, which is particularly important for complex or low-symmetry materials. However, higher resolution can reduce acquisition speed, so the appropriate balance depends on the analysis objective.
EBSD acquisition time can range from seconds to several hours, depending on the measurement objective and experimental setup. Key factors include the size of the mapped area, step size, and detector acquisition speed. Modern EBSD detectors can acquire hundreds to thousands of patterns per second, supporting rapid collection of large datasets. SEM operating conditions, such as beam current, and sample quality can also influence acquisition time, as longer exposure times might be required to achieve sufficient pattern quality for reliable indexing.
To help plan measurements, some EBSD software, such as AZtec, include optimisation tools that estimate acquisition time from the selected experimental parameters.
Yes, EBSD is often combined with other SEM-based techniques to provide complementary microstructural information. One of the most common combinations is EBSD with Energy Dispersive X-ray Spectroscopy (EDS), which links crystallographic and chemical information. EBSD is also frequently used alongside Forward Scatter Electron (FSE) imaging to provide orientation and microstructural contrast information. It can also be combined with Focussed Ion Beam (FIB) milling for three-dimensional EBSD or site-specific cross-sectional analysis and with in-situ
techniques to study microstructural changes during an experiment.
Effective correlative analysis requires an SEM configuration that supports all relevant modalities. Some SEM platforms support simultaneous data collection from multiple detectors through optimised detector design, positioning, and integrated software workflows.
Transmission Kikuchi Diffraction (TKD) is an SEM-based diffraction technique related to EBSD that is used to analyse very fine-grained and nanocrystalline materials. Unlike conventional EBSD, where diffraction patterns are generated by backscattered electrons, TKD uses electrons transmitted through a thin sample to generate Kikuchi patterns. This significantly improves spatial resolution and enables crystallographic analysis at the nanoscale.
Read more about TKD here.
Reflected Kikuchi Diffraction (RKD) is a diffraction technique related to EBSD in which the sample is not tilted, and the detector is positioned above the sample, near or around the pole piece. Like EBSD, RKD analyses Kikuchi diffraction patterns generated from electron interactions within a crystalline material. However, this geometry produces a significantly weaker diffraction signal than conventional EBSD at a sample tilt of approximately 70°. Its main benefit is the ability to work with larger samples as the RKD setup does not require samples to be tilted and thereby is not limited by space around the pole piece.
Learn more about Electron Backscatter Diffraction on ebsd.com.
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