Micro-XRF on SEM

QUANTAX Micro-XRF with XTrace

Micro-XRF Analysis on SEM

XTrace Mounted on a SEM

X-ray excitation is far more efficient than electron excitation in the mid to heavy element range, sensitivity is 20 to 50 times better. Depending on element and matrix, limits of detection down to 10 ppm can be reached. This enables trace element analysis in the SEM.

Designed for optimum performance

XTrace Functional Principle
Functional principle of Micro-XRF analysis
with the XTrace micro-spot X-ray source

XTrace is equipped with polycapillary optics that focuses the X-ray beam of a low power micro-focus tube to spot sizes below 40 µm for Mo Kα radiation. The focal spot can be aligned perfectly with the SEM electron beam ensuring analysis of the same sample location. Additionally, the working distance of XTrace has been set to a value of around 10 mm. The positive effect is that the optics is far enough away to not interfere with normal SEM operation but still close enough to provide excellent excitation intensity. Count rates of about 40 kcps can be obtained using a 30 mm2 detector.

Excellent excitation under all conditions

Resolution Tests with a Siemens Star
Maps of a chromium Siemens star,
showing the excellent resolution attainable
with XTrace, which can be further
improved by tilting it towards the X-ray

The tube of the XTrace X-ray source is equipped with a set of filters that can be rotated into place to produce the desired excitation spectrum and to suppress diffraction peaks on crystalline samples.

Shadowing and artifacts caused by sample topography can be counteracted by tilting the sample towards the X-ray source and so irradiating it perpendicularly. Another useful effect of this procedure is the further improvement of spatial resolution as the Siemens star maps show.

Perfect integration with QUANTAX EDS

QUANTAX Micro-XRF uses the detector and signal processing chain of a QUANTAX EDS system. The XFlash® detector of QUANTAX EDS ensures excellent energy resolution and the signal processing electronics' highest possible speed.

Both systems are controlled by the ESPRIT 2.0 software under a single interface. Methods can be changed with the click of the mouse. Results of both methods can be combined for optimum accuracy, making perfect use of the light element performance of electron induced EDS and the sensitivity for heavier elements of XRF.

The software also supports measurement of objects, line scans and maps using the SEM specimen stage. Maps and line scans are stored with full spectra at every point (HyperMaps) and can thus be processed on- or offline.

Download the XTrace brochure (PDF)