Quantification of series of X-ray spectra taken at different tilts in analytical transmission electron microscopy

In 2007, it was suggested that by varying the take-off angle between repeated measurements of the same region in energy-dispersive X-ray spectroscopy (EDXS) in a transmission electron microscope (TEM) a significant improvement of the accuracy of X-ray quantification could be achieved. Simultaneously, an analytical expression of the depth within the thin foil specimen of the feature analysed was derived, which in turn could be used to better quantify the material of interest. Simulated results for the absorption of a variety of X-rays in different semiconductor substrates using different Monte Carlo programs will be presented, specifically regarding a model which corrects for tilting the specimen toward or away from the detector: a common method of varying the take-off angle. A set of experimental EDX spectra of capped InAs quantum wells or dots taken in plan-view geometry by tilting the specimen holder will be used for comparison of experimental with the simulated data.