The Stanford Mineral and Microchemical Analysis Facility is equipped with a state-of-the-art JEOL JXA-8230 “SuperProbe” electron microprobe. The electron microprobe measures the elemental compositions of solid samples by detecting the X-rays emitted on excitation by a focused electron beam, down to a spatial resolution of about 1 micron. All elements heavier than beryllium can be detected, at concentrations as low as 10’s of ppm. Highly quantitative analyses are made using 5 wavelength dispersive X-ray spectrometers (WDS) with calibrations based on known standard materials. Compositional images (maps) can readily be obtained with backscattered electrons (sensitive primarily to mean atomic number), or with WDS or EDS X-ray data.  The instrument is adjacent to the Stanford Nanocharacterization Laboratory (SNL), at the west end of the first floor of the McCullough Building.  

The microprobe is equipped with an “xCLENT III” advanced hyperspectral cathodoluminescence (CL) system, which provides full color images, as well as point-by-point optical spectra, of the visible light emissions induced by the scanning electron beam. Such images are often very useful for rapid mapping of mineral or alloy distributions in complex samples, seeing patterns of zoning in distributions of trace elements in individual grains, or evaluating structural/lattice defects in various materials. CL data can be readily combined with X-ray and electron signals at each point to provide great flexibility in mapping composition and phase distribution. 

The Stanford Electron Microprobe Laboratory has an experienced staff that have worked on a variety of applications ranging from geological and biologic materials to nano-particles and integrated circuits. The quality of every dataset produced in the laboratory is evaluated by lab staff prior to being sent to the user and/or PI (data quality is evaluated, no data interpretation). In addition, we also have experience interpreting and modeling data, evaluating and qualifying materials for applications, and performing root-cause failure analyses, and are happy to provide further assistance if needed.