The electron probe microanalyzer, a versatile tool for the analysis of areas as small as one micron in diameter, has been used at Goddard Space Flight Center in applications ranging from materials research to analysis of failures in mechanical parts. Methods of using the probe and representative results obtained are illustrated by several examples that include bonding of thermoelectric materials, alloy development, and analysis of materials failure.

In 1968, the National Bureau of Standards (NBS) published Special Publication 298 "Quantitative Electron Probe Microanalysis," which contained proceedings of a seminar held on the subject at NBS in the summer of 1967. This publication received wide interest that continued through the years far beyond expectations. The present volume, also the result of a gathering of international experts, in 1988, at NBS (now the National Institute of Standards and Technology, NIST), is intended to fulfill the same purpose. After years of substantial agreement on the procedures of analysis and data evaluation, several sharply differentiated approaches have developed. These are described in this publi cation with all the details required for practical application. Neither the editors nor NIST wish to endorse any single approach. Rather, we hope that their exposition will stimulate the dialogue which is a prerequisite for technical progress. Additionally, it is expected that those active in research in electron probe microanalysis will appreciate more clearly the areas in which further investigations are warranted.

The combination of electron microprobe x-ray emission spectrometry with the scanning techniques first developed for the scanning electron microscope permits using the scanning electron probe as a microscope sensitive to elemental composition. This technique is particularly useful in the many applications in which spatial distribution of one or more elements in a specimen is more important than local composition. Although oscilloscope representation of probe scanning is usually obtained by the simple technique of producing a dot of light for each arriving photon, more sophisticated scanning techniques such as expanded contrast registration and concentration mapping can provide more quantitative information. Signals other than x-rays, such as target current, electron backscatter, or cathodoluminescence may be used for image formation. Electron beam scanning can also be performed in a discontinuous fashion, so that the electron beam irradiates in succession a number of spots arranged in a square or rectangular pattern, and the number of photons registered in each position is retained in the memory of a multichannel analyzer. The application of these diverse scanning techniques is illustrated. (Author).

The Advanced Study Institute provided an opportunity for researchers in universities, industry and National and International Laboratories, from the disciplines ofmaterials science, physics, chemistry and engineering to meet together in an assessment of the impact of electron and scanning probe microscopy on advanced material research. Since these researchers have traditionally relied upon different approaches, due to their different scientific background, to advanced materials problem solving, presentations and discussion within the Institute sessions were initially devoted to developing a set ofmutually understood basic concepts, inherently related to different techniques ofcharacterization by microscopy and spectroscopy. Particular importance was placed on Electron Energy Loss Spectroscopy (EELS), Scanning Probe Microscopy (SPM), High Resolution Transmission and Scanning Electron Microscopy (HRTEM, HRSTEM) and Environmental Scanning Electron Microscopy (ESEM). It was recognized that the electronic structure derived directly from EELS analysis as well as from atomic positions in HRTEM or High Angle Annular Dark Field STEM can be used to understand the macroscopic behaviour of materials. The emphasis, however, was upon the analysis of the electronic band structure of grain boundaries, fundamental for the understanding of macroscopic quantities such as strength, cohesion, plasticity, etc.

The Use of Electron Probe MicroAnalysis to Determine the Thickness of Thin Films in Materials Science.