PhotoMetrics, Inc.
15801 Graham St.
Huntington Beach CA 92649
(714) 895-4465
Fax (714) 893-4682
e-mail: lab@photometrics.net

Energy Dispersive X-Ray Spectroscopy (EDS)

EDS identifies the elemental composition of materials imaged in a Scanning Electron Microscope (SEM) for all elements with an atomic number greater than boron. Most elements are detected at concentrations on the order of 0.1%.

Applications include

Materials evaluation and identification

Contaminants
Elemental diffusion profiles
Glassivation phosphorus content
Multiple spot analysis of areas from 1 micron to 10 cm in diameter

Failure analysis

Contamination identification
Unknowns identification
Stringer location and identification

Quality control screening

Material verification
Plating specification and certification

Principle of Operation

As the electron beam of the SEM is scanned across the sample surface, it generates X-ray fluorescence from the atoms in its path. The energy of each X-ray photon is characteristic of the element which produced it. The EDS microanalysis system collects the X-rays, sorts and plots them by energy, and automatically identifies and labels the elements responsible for the peaks in this energy distribution.

The EDS data are typically compared with either known or computer-generated standards to produce a full quantitative analysis showing the sample composition.

Data output plots the original spectrum showing the number of X-rays collected at each energy, as seen above. Maps of element distributions over areas of interest and quantitative composition tables can also be provided as necessary.