EDS

Method Specification

Energy dispersive x-ray spectroscopy (EDS) is widely used as a chemical analysis technique in scanning electron microscopy (SEM). It enables the detection of elements both qualitatively and quantitatively simultaneously with any imaging mode of the SEM. In the last decade the technology of EDS has tremendously improved as the SiLi detectors were replaced by silicon drift detectors (SDD), it resulted in larger area detectors with higher counts rates. The Bruker X-Flash 60mm detector is installed on all the SEMs in the EM unit beside the Zeiss Supra 55. It has a 126eV spectral resolution and is applicable for wide range of samples in materials and biological sciences. Recently we added the Bruker FlatQuad EDS detector. It has an annular four- channel silicon drift detector, which translates into a fast and sensitive chemical analysis detection. The big advantage over the old generation EDS systems is its ability to detect low energy x-ray lines such as m and l line series for heavy elements. Furthermore the fast detection combined with the low acceleration voltages required can minimize the damage for beam sensitive materials.
All EDS measurements can be performed at low temperatures (liquid nitrogen), high temperatures (up to 200°C) and also under low vacuum and wet mode conditions. Therefore a wide variety of samples at different atmospheres and temperatures can be chemically analyzed.

EDS automation is used for the chemical analysis of large number of particles or very large samples that require a full scanning and EDS analysis. The Bruker ESPRIT feature is a software package developed for particle detection and chemical classification in EDS. The Feature module brings additional capabilities to the existing microanalysis package that we have. It has the ability to automatically detect, measure and analyze any kind of particle or feature, whilst providing its chemical classification using the high throughput capability of the Xflash 60mm or the FlatQuad silicon drift detectors. The feature analysis can be automated via ESPRIT Jobs. All settings and methods can be selected for a fully automated feature and chemical classification run, permitting unattended analysis of large areas and samples. The Jobs automated feature analysis of large areas include: image acquisition, particle detection, chemical classification, overview image, reports and data export.