Search

This thoroughly revised and updated Fourth Edition of a time-honored text provides the reader with a comprehensive introduction to the field of scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS) for elemental microanalysis, electron backscatter diffraction analysis (EBSD) for micro-crystallography, and focused ion beams. Students and academic researchers will find the text to be an authoritative and scholarly resource, while SEM operators and a diversity of practitioners — engineers, technicians, physical and biological scientists, clinicians, and technical managers — will find that every chapter has been overhauled to meet the more practical needs of the technologist and working professional. In a break with the past, this Fourth Edition de-emphasizes the design and physical operating basis of the instrumentation, including the electron sources, lenses, detectors, etc. In the modern SEM, many of the low level instrument parameters are now controlled and optimized by the microscope's software, and user access is restricted. Although the software control system provides efficient and reproducible microscopy and microanalysis, the user must understand the parameter space wherein choices are made to achieve effective and meaningful microscopy, microanalysis, and micro-crystallography. Therefore, special emphasis is placed on beam energy, beam current, electron detector characteristics and controls, and ancillary techniques such as energy dispersive x-ray spectrometry (EDS) and electron backscatter diffraction (EBSD).With 13 years between the publication of the third and fourth editions, new coverage reflects the many improvements in the instrument and analysis techniques. The SEM has evolved into a powerful and versatile characterization platform in which morphology, elemental composition, and crystal structure can be evaluated simultaneously. Extension of the SEM into a'dual beam'platform incorporating bothelectron and ion columns allows precision modification of the specimen by focused ion beam milling. New coverage in the Fourth Edition includes the increasing use of field emission guns and SEM instruments with high resolution capabilities, variable pressure SEM operation, theory, and measurement of x-rays with high throughput silicon drift detector (SDD-EDS) x-ray spectrometers. In addition to powerful vendor- supplied software to support data collection and processing, the microscopist can access advanced capabilities available in free, open source software platforms, including the National Institutes of Health (NIH) ImageJ-Fiji for image processing and the National Institute of Standards and Technology (NIST) DTSA II for quantitative EDS x-ray microanalysis and spectral simulation, both of which are extensively used in this work. However, the user has a responsibility to bring intellect, curiosity, and a proper skepticism to information on a computer screen and to the entire measurement process. This book helps you to achieve this goal.Realigns the text with the needs of a diverse audience from researchers and graduate students to SEM operators and technical managersEmphasizes practical, hands-on operation of the microscope, particularly user selection of the critical operating parameters to achieve meaningful resultsProvides step-by-step overviews of SEM, EDS, and EBSD and checklists of critical issues for SEM imaging, EDS x-ray microanalysis, and EBSD crystallographic measurementsMakes extensive use of open source software: NIH ImageJ-FIJI for image processing and NIST DTSA II for quantitative EDS x-ray microanalysis and EDS spectral simulation.Includes case studies to illustrate practical problem solvingCovers Helium ion scanning microscopyOrganized into relatively self-contained modules – no need to'read it all'to understand a topicIncludesan

In the decade since the publication of the second edition of Scanning Electron Microscopy and X-Ray Microanalysis, there has been a great expansion in the capabilities of the basic scanning electron microscope (SEM) and the x-ray spectrometers. The emergence of the variab- pressure/environmental SEM has enabled the observation of samples c- taining water or other liquids or vapor and has allowed for an entirely new class of dynamic experiments, that of direct observation of che- cal reactions in situ. Critical advances in electron detector technology and computer-aided analysis have enabled structural (crystallographic) analysis of specimens at the micrometer scale through electron backscatter diffr- tion (EBSD). Low-voltage operation below 5 kV has improved x-ray spatial resolution by more than an order of magnitude and provided an effective route to minimizing sample charging. High-resolution imaging has cont- ued to develop with a more thorough understanding of how secondary el- trons are generated. The?eld emission gun SEM, with its high brightness, advanced electron optics, which minimizes lens aberrations to yield an - fective nanometer-scale beam, and “through-the-lens” detector to enhance the measurement of primary-beam-excited secondary electrons, has made high-resolution imaging the rule rather than the exception. Methods of x-ray analysis have evolved allowing for better measurement of specimens with complex morphology: multiple thin layers of different compositions, and rough specimens and particles. Digital mapping has transformed classic x-ray area scanning, a purely qualitative technique, into fully quantitative compositional mapping.

From its early days in the 1950s, the electron microanalyzer has offered two principal ways of obtaining x-ray spectra: wavelength dispersive spectrometry (WDS), which utilizes crystal diffraction, and energy dispersive spectrometry (EDS), in which the x-ray quantum energy is measured directly. In general, WDS offers much better peak separation for complex line spectra, whereas EDS gives a higher collection efficiency and is easier and cheaper to use. Both techniques have undergone major transformations since those early days, from the simple focusing spectrometerand gas proportional counter of the 1950s to the advanced semiconductor detectors and programmable spectrometersoftoday. Becauseofthesedevelopments, thecapabilities and relative merits of EDS and WDS techniques have been a recurring feature of microprobeconferences for nearly40 years, and this volume bringstogetherthepapers presented at the Chuck Fiori Memorial Symposium, held at the Microbeam Analysis Society Meeting of 1993. Several themes are apparent in this rich and authoritative collection of papers, which have both a historical and an up-to-the-minute dimension. Light element analysis has long been a goal of microprobe analysts since Ray Dolby first detected K radiation with a gas proportional counter in 1960. WDS techniques (using carbon lead stearate films) were not used for this purpose until four years later. Now synthetic multilayers provide the best dispersive elements for quantitative light element analy­ sis-still used in conjunction with a gas counter.