Specific Process Knowledge/Characterization/Element analysis: Difference between revisions
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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 | 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 | ||
these ions will be able to gradually sputter off the surface atoms in a small area. In this way one layer after another is peeled off the sample. Some of the surface atoms are emitted as ionized particles. | these ions will be able to gradually sputter off the surface atoms in a small area defined by the raster pattern. In this way one layer after another is peeled off the sample. Some of the surface atoms are emitted as ionized particles. | ||
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. | 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. | ||