Angle-resolved cathodoluminescence (ARCL) can be useful to capture the emission pattern of the light emitted from a specimen (angular distribution, θ, and Φ in polar coordinates). You can collect individual emission patterns from a few well-chosen points—typically giving the highest quality patterns. Or you can map and analyze a complete emission pattern at each point (pixel) of an image—analogous to spectrum imaging.
The workflow is as follows:
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Locate the region of interest within the sample.
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Set the desired SEM conditions.
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Ensure the alignment of the CL system to the SEM and sample is correct.
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Define the position of the electron beam.
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Optimize the emission pattern (optional).
In the following section, we will focus on capturing an emission pattern and optimizing the system to maximize angular (and spectral) information and signal-to-noise ratio.