X-Ray Spectrometry in Electron Beam Instruments


Book Description

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.




Scanning Electron Microscopy and X-Ray Microanalysis


Book Description

This book has evolved by processes of selection and expansion from its predecessor, Practical Scanning Electron Microscopy (PSEM), published by Plenum Press in 1975. The interaction of the authors with students at the Short Course on Scanning Electron Microscopy and X-Ray Microanalysis held annually at Lehigh University has helped greatly in developing this textbook. The material has been chosen to provide a student with a general introduction to the techniques of scanning electron microscopy and x-ray microanalysis suitable for application in such fields as biology, geology, solid state physics, and materials science. Following the format of PSEM, this book gives the student a basic knowledge of (1) the user-controlled functions of the electron optics of the scanning electron microscope and electron microprobe, (2) the characteristics of electron-beam-sample inter actions, (3) image formation and interpretation, (4) x-ray spectrometry, and (5) quantitative x-ray microanalysis. Each of these topics has been updated and in most cases expanded over the material presented in PSEM in order to give the reader sufficient coverage to understand these topics and apply the information in the laboratory. Throughout the text, we have attempted to emphasize practical aspects of the techniques, describing those instru ment parameters which the microscopist can and must manipulate to obtain optimum information from the specimen. Certain areas in particular have been expanded in response to their increasing importance in the SEM field. Thus energy-dispersive x-ray spectrometry, which has undergone a tremendous surge in growth, is treated in substantial detail.




Electron Probe Quantitation


Book Description

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.




Principles of Analytical Electron Microscopy


Book Description

Since the publication in 1979 of Introduction to Analytical Electron Microscopy (ed. J. J. Hren, J. I. Goldstein, and D. C. Joy; Plenum Press), analytical electron microscopy has continued to evolve and mature both as a topic for fundamental scientific investigation and as a tool for inorganic and organic materials characterization. Significant strides have been made in our understanding of image formation, electron diffraction, and beam/specimen interactions, both in terms of the "physics of the processes" and their practical implementation in modern instruments. It is the intent of the editors and authors of the current text, Principles of Analytical Electron Microscopy, to bring together, in one concise and readily accessible volume, these recent advances in the subject. The text begins with a thorough discussion of fundamentals to lay a foundation for today's state-of-the-art microscopy. All currently important areas in analytical electron microscopy-including electron optics, electron beam/specimen interactions, image formation, x-ray microanalysis, energy-loss spectroscopy, electron diffraction and specimen effects-have been given thorough attention. To increase the utility of the volume to a broader cross section of the scientific community, the book's approach is, in general, more descriptive than mathematical. In some areas, however, mathematical concepts are dealt with in depth, increasing the appeal to those seeking a more rigorous treatment of the subject.




Energy Dispersive Spectrometry of Common Rock Forming Minerals


Book Description

This book provides a very basic introduction to electron microscopy and energy dispersive spectrometry (EDS). It has the largest compiled collection of EDS spectra ever published and covers most common rock forming minerals. In addition, it provides a key to help the novice wade through the large number of spectra.




Handbook of Sample Preparation for Scanning Electron Microscopy and X-Ray Microanalysis


Book Description

Scanning electr on microscopy (SEM) and x-ray microanalysis can produce magnified images and in situ chemical information from virtually any type of specimen. The two instruments generally operate in a high vacuum and a very dry environment in order to produce the high energy beam of electrons needed for imaging and analysis. With a few notable exceptions, most specimens destined for study in the SEM are poor conductors and composed of beam sensitive light elements containing variable amounts of water. In the SEM, the imaging system depends on the specimen being sufficiently electrically conductive to ensure that the bulk of the incoming electrons go to ground. The formation of the image depends on collecting the different signals that are scattered as a consequence of the high energy beam interacting with the sample. Backscattered electrons and secondary electrons are generated within the primary beam-sample interactive volume and are the two principal signals used to form images. The backscattered electron coefficient ( ? ) increases with increasing atomic number of the specimen, whereas the secondary electron coefficient ( ? ) is relatively insensitive to atomic number. This fundamental diff- ence in the two signals can have an important effect on the way samples may need to be prepared. The analytical system depends on collecting the x-ray photons that are generated within the sample as a consequence of interaction with the same high energy beam of primary electrons used to produce images.




Remote Compositional Analysis


Book Description

Comprehensive overview of the spectroscopic, mineralogical, and geochemical techniques used in planetary remote sensing.




Electron Microprobe Analysis and Scanning Electron Microscopy in Geology


Book Description

Originally published in 2005, this book covers the closely related techniques of electron microprobe analysis (EMPA) and scanning electron microscopy (SEM) specifically from a geological viewpoint. Topics discussed include: principles of electron-target interactions, electron beam instrumentation, X-ray spectrometry, general principles of SEM image formation, production of X-ray 'maps' showing elemental distributions, procedures for qualitative and quantitative X-ray analysis (both energy-dispersive and wavelength-dispersive), the use of both 'true' electron microprobes and SEMs fitted with X-ray spectrometers, and practical matters such as sample preparation and treatment of results. Throughout, there is an emphasis on geological aspects not mentioned in similar books aimed at a more general readership. The book avoids unnecessary technical detail in order to be easily accessible, and forms a comprehensive text on EMPA and SEM for geological postgraduate and postdoctoral researchers, as well as those working in industrial laboratories.




Volatiles in the Martian Crust


Book Description

Volatiles in the Martian Crust is a vital reference for future missions - including ESA's EXO Mars and NASA's Mars2020 rover - looking for evidence of life on Mars and the potential for habitability and human exploration of the Martian crust. Mars science is a rapidly evolving topic with new data returned from the planet on a daily basis. The book presents chapters written by well-established experts who currently focus on the topic, providing the reader with a fresh, up-to-date and accurate view. Organized into two main sections, the first half of the book focuses on the Martian meteorites and specific volatile elements. The second half of the book explores processes and locations on the crust, including what we have learned about volatile mobility in the Martian crust. Coverage includes data from orbiter and in situ rovers and landers, geochemical and geophysical modeling, and combined data from the SNC meteorites. - Presents information about the nature, relationship, and reactivity of chemical elements and compounds on Mars - Explores the potential habitability of Mars - Provides a comprehensive view of volatiles in the Martian crust from studies of actual samples as well as from the variety of landed missions, including the MER and Curiosity rovers - Delivers a vital reference for ongoing and future missions to Mars while synthesizing large data sets and research on volatiles in the Martian atmosphere - Concludes with an informative summary chapter that looks to future Mars missions and what might be learned




An Introduction to Surface Analysis by XPS and AES


Book Description

Provides a concise yet comprehensive introduction to XPS and AES techniques in surface analysis This accessible second edition of the bestselling book, An Introduction to Surface Analysis by XPS and AES, 2nd Edition explores the basic principles and applications of X-ray Photoelectron Spectroscopy (XPS) and Auger Electron Spectroscopy (AES) techniques. It starts with an examination of the basic concepts of electron spectroscopy and electron spectrometer design, followed by a qualitative and quantitative interpretation of the electron spectrum. Chapters examine recent innovations in instrument design and key applications in metallurgy, biomaterials, and electronics. Practical and concise, it includes compositional depth profiling; multi-technique analysis; and everything about samples—including their handling, preparation, stability, and more. Topics discussed in more depth include peak fitting, energy loss background analysis, multi-technique analysis, and multi-technique profiling. The book finishes with chapters on applications of electron spectroscopy in materials science and the comparison of XPS and AES with other analytical techniques. Extensively revised and updated with new material on NAPXPS, twin anode monochromators, gas cluster ion sources, valence band spectra, hydrogen detection, and quantification Explores key spectroscopic techniques in surface analysis Provides descriptions of latest instruments and techniques Includes a detailed glossary of key surface analysis terms Features an extensive bibliography of key references and additional reading Uses a non-theoretical style to appeal to industrial surface analysis sectors An Introduction to Surface Analysis by XPS and AES, 2nd Edition is an excellent introductory text for undergraduates, first-year postgraduates, and industrial users of XPS and AES.