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| | style="background:WhiteSmoke; color:black" | Quite fast and easy | | | style="background:WhiteSmoke; color:black" | Quite fast and easy |
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| == Secondary Ion Mass Spectrometry (SIMS) ==
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| In the Atomika SIMS the samples are bombarded with a beam of either oxygen or caesium ions. When accelerated to high energy and rastered across the sample
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| these ions will be able to gradually sputter off the surface atoms in a small area defined by the raster pattern. Some of the surface atoms are emitted as ionized particles. In this way one layer after another is peeled off the sample.
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| These charged species are led through a mass spectrometer where a magnetic field is used to deflect them. The deflection increases with charge and decreases with mass and we are therefore able detect and count them according to their mass. This technique is called Secondary Ion Mass Spectrometry or SIMS.
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| === Typical application of SIMS ===
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| SIMS is the most sensitive technique for elemental composition. It is therefore ideal if you want to check doping profiles or for contaminations.
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| A typical application would be to check the concentration profile of boron doping in silicon. In that case one would put two samples into the SIMS.
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| * A reference sample with a known boron profile
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| * A sample
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