What is EDS?
Energy dispersive x-ray spectroscopy (EDS, EDX, XEDS, etc.) is an analytical technique used for analysis and characterization of a sample.
Elemental composition analysis is key to understanding foreign materials, coating composition, small component materials, rapid alloy identify, evaluating corrosion, plus phase identification and distribution. EDS tools from Gatan provide qualitative and quantitative insight, in addition to elemental maps for microstructure determination during these types of material studies.
Since the changing local chemical environment atomic bonding has little effect on EDS, it is not a preferred technique for specimen chemical analysis. However, it is excellent to determine the elemental distribution of a sample. Used in combination with electron energy loss spectroscopy (EELS), you can easily analyze both the chemical and compositional makeup of your specimen.
Unlike similar techniques, EDS requires minimal setup and is used in semi-thin to bulk specimens; thickness options are unlimited. EDS also offers a high signal-to-background ratio (SBR). Some limitations of EDS include: non-local fluorescence; low-Z limits; and limited thin film signal-to-noise ratio (SNR).
In the example below, the Sr L2,3-edges at 1940 eV were not within the 0 – 850 eV energy range (top) after an EELS analysis was run on a semiconductor sample. When spectrum imaging was used to obtain the EDS Sr elemental map in combination with the EELS Ti, Fe, and La maps (bottom), the collective color map shows the distribution of each element across an extended energy range.
For more information about the comparison between this technique and other analytical techniques, please visit EELS.info, an educational site.