Trace elemental analysis at nanometer spatial resolution by parallel-detection electron energy loss spectroscopy.

R D Leapman; D E Newbury

doi:10.1021/ac00066a003

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Trace elemental analysis at nanometer spatial resolution by parallel-detection electron energy loss spectroscopy.

R D Leapman·D E Newbury

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Abstract

Parallel-detection electron energy loss spectroscopy (EELS) combined with scanning transmission electron microscopy (STEM) and a field emission source provides an unprecedented sensitivity for elemental microanalysis. By deflecting the energy loss spectrum across a parallel detector and computing the difference spectrum from sequentially collected energy-shifted spectra, the effects due to detector pattern noise are nearly eliminated so that signals less than 0.1% of the background can be readily detected. Measurements on a series of glass standard reference materials show that EELS provides both high spatial resolution and trace sensitivity at the 10 atomic ppm level for a wide range of elements including the alkaline earths, 3-d transition metals, and the lanthanides. For analytical volumes with dimensions of the order of 10 nm, this translates into near-single atom detectability.

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R D Leapman, D E Newbury. 1993-09-15. Trace elemental analysis at nanometer spatial resolution by parallel-detection electron energy loss spectroscopy.. https://doi.org/10.1021/ac00066a003

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