Video Upload Options

Energy-dispersive X-ray spectroscopy (EDS, also EDX or EDAX) is an analytical microanalysis technique used for the elemental characterization of a sample. When a focused beam of high-energy electrons is directed at a specimen — typically within a scanning electron microscope (SEM) or electron probe microanalyzer (EPMA) — inner-shell ionization of the atoms in the interaction volume produces characteristic X-rays whose photon energies are element-specific ^[1]. An energy-dispersive spectrometer, usually a cooled silicon drift detector or Si(Li) detector, records the emitted X-rays by energy simultaneously, producing a spectrum in which peak energies identify the elements present and peak areas quantify their concentrations ^[2]. The technique is conventionally applied to elements heavier than sodium (Z ≥ 11), although modern detectors extend routine light-element detection to beryllium ^[3]. EDS is distinguished from wavelength-dispersive X-ray spectroscopy (WDS) by its parallel acquisition of the full X-ray energy spectrum, shorter acquisition time, and generally lower energy resolution; quantitative analysis requires correction for atomic number effects, absorption, and secondary fluorescence, as specified in ASTM E1508 ^[3].