EBSD
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Technical Concept |
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Electron Back Scatter Diffraction（EBSD）installed in SEM is a powerful technology for identifying the crystal orientation by diffraction from electron beam. |
Recently, EBSD as a well-established accessory for the SEM to characterize microstructure is of great interest to be employed in the semiconductor industry. EBSD installed in SEM is a powerful technology for identifying the crystal orientation by diffraction from electron beam.
The optimum efficiency of diffraction signals will be collected if specimen surface makes an angle of 70° with electron beam inside the SEM chamber. Electron beam applied on specimen surface enables the backscattering electrons to take form. The diffraction phenomenon caused by these backscattering electrons will lead to the formation of Kikuchi lines and patterns once they go through the specimen surface. The relative signals and information accompanied by Kikuchi lines and patterns analyzed by EBSD detector can determine the crystal orientation for each grain.
After confirming the crystal orientation and diffraction situation of grains, further studies such as characterizing the boundaries, texture investigations, and strain analyses will be practicable. Additionally, study on phase deification and phase distribution is also achievable if EBSD works cooperatively with EDX.
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Applications |
- Substructure analyses
- Grain size / grain boundary distribution
- Crystal orientation analyses
- Phase identification and distribution
- Deformed and Recrystallized structures analyses
- Texture analyses
- Strain analyses
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Application cases |
Orientation Map |
Phase Map |
Grain size distribution |
Misotientation angle distribution |
Pole figure |
Inverse pole figure |
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Q & A |
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Q1．What dimension of specimen can be allowed for EBSD ? |
A．Basically the size no larger than 1cm, 1cm, and 0.5cm will be accepted for the length, width, and height, respectively. To discuss your specimen with the technical unit prior to analysis is recommended.
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Q2．What are the specimen requirements prior to EBSD analysis ? |
A．specimen surface flat enough is absolutely mandatory for EBSD analysis. EBSD image quality always shows a high dependence on surface conditions.
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Q3．How small of the mosorientation angle between grains can be distinguished by EBSD ? |
A．0.05° in an ideal case.
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Q4．Why a sample needs an EBSD analysis ? |
A．It makes sense to analyze the crystalline materials by EBSD. TEM and SEM are incapable of quantifying the distribution of grain dimension and crystal misorientation even though they had successfully observed the grain morphologies with high resolution.
EBSD possesses a function of a large-scanning area for covering a larger number of grains. This tech is able to realize the phase identification and distribution, statistics collection of grain size and misorientation between grains.
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Q5．What is the minimum distinguishable grain size under an EBSD technology ? |
A．The analyzed limit of grain size is about 50nm. Actually, the condition of specimen surface has a significant effect on EBSD analyses. In general, a high flatness of specimen surface is preferred.
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