Table Of ContentMikrochimica
Acta
Supplementum 12
A. Boekestein and M. K. Pavicevic (eds.)
Electron Microbeam Analysis
Springer-Verlag Wien GmbH
Dr. Abraham Boekestein
Head Department Instrumental Analysis
Agricultural Research Department (DLO-NL)
State Institute for Quality Control of Agricultural Products (RIKILT-DLO)
Wageningen, The Netherlands
Prof. Miodrag K. Pavicevic
Institute of Mineralogy, University of Salzburg, Austria
Permanent address: Faculty of Mining and Geology, University of Belgrade, Yugoslavia
This work is subject to copyright.
All rights are reserved, whether the whole or part of the material is concerned, specifically
those of translation, reprinting, re-use of illustrations, broadcasting, reproduction by photo
copying machine or similar means, and storage in data banks.
© 1992 Springer-Verlag Wien
Typesetting : Asco Trade Typesetting Limited, Hong Kong
With 157 Figures
ISSN 0026-3672
ISBN 978-3-211-82359-0 ISBN 978-3-7091-6679-6 (eBook)
DOI 10.1007/978-3-7091-6679-6
Preface
This supplement of Mikrochimica Acta contains selected papers from the
Second Workshop of the European Microbeam Analysis Society (EMAS)
on "Modern Developments and Applications in Microbeam Analysis",
which took place in May 1991 in Dubrovnik (Yugoslavia).
EMAS was founded in 1987 by members from almost all European
countries, in order to stimulate research, applications and development of
all forms of microbeam methods. One of the most important activities
EMAS is the organisation of biannual workshops for demonstrating the
current status and developing trends of microbeam methods. For this
meeting, EMAS chose to highlight the following topics: electron-beam
microanalysis (EPMA) of thin films and quantitative analysis of ultra-light
elements, Auger electron spectroscopy (AES), electron energy loss spec
trometry (EELS), high-resolution transmission electron microscopy
(HRTEM), quantitative analysis of biological samples and standard-less
electron-beam microanalysis.
Seven introductory lectures and almost seventy poster presentations
were given by speakers from twelve European and two non-European
(U.S.A. and Argentina) countries were made. One cannot assume that all
fields of research in Europe were duly represented, but a definite trend is
discernible. EPMA with wavelength-dispersive spectrometry (WDS) or
energy-dispersive spectrometry (EDS) is the method with by far the widest
range of applications, followed by TEM with EELS and then AES. There
are also interesting suggestions for the further development of new appa
ratus with new fields of application. Applications are heavily biased
towards materials science (thin films in microelectronics and semicon
ductors), ceramics and metallurgy, followed by analysis of biological and
mineral samples.
This issue contains the full texts of five introductory lectures and 25
brief articles. Sixteen contributions relate to the refinement of methods and
procedures and nine of these are concerned with important applications in
various fields. All submissions have been refereed according to the usual
procedures.
At the end of this issue is an overview of all the published work. We
hope that these contributions to the field of electron microbeam analysis
will be found to be useful.
February 1992 A. Boekestein and M. K. Pavicevic
Participants in the EMAS '91 Meeting in Dubrovnik
Contents
Listed in Current Contents
EPMA - A Versatile Technique for the Characterization of Thin
Films and Layered Structures.
P. Willich . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1
Quantitative EPMA of the Ultra-Light Elements Boron Through
Oxygen.
G. F. Bastin, H. J. M. Heijligers . . . . . . . . . . . . . . . . . . . .. 19
Auger Microscopy and Electron Probe Microanalysis.
J. Cazaux ....................... . 37
Quantitative X-Ray Microanalysis of Ultra-Thin Resin-Embedded
Biological Samples.
H. Y. Eler, S. M. Wilson, W A. P. Nicholson, J. D. Pediani, S. A.
McWilliams, D. McEwan Jenkinson, Ch. J. Kenyon . . . . . . . . 53
Analytical and High-Resolution Electron Microscopy Studies at
Metal/Ceramic Interfaces.
M. Ruhle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Quantitative Electron Probe Microanalysis of Multi-layer Structures.
G. F. Bastin, J. M. Dijkstra, H. J. M. Heijliger, D. Klepper ...... 93
Comparison of (/J (pz) Curve Models in EPMA.
J. A. Riveros, G. E. Castellano, J. C. Trincavelli ..... . 99
Quantitative Electron Probe Microanalysis: New Accurate (/J (pz)
Description.
C. Merlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
A Modular Universal Correction Procedure for Quantitative EPMA.
/. Farthing, G. Love, V. D. Scott, C. T. Walker . . . . . . . . . . . . . 117
Monte Carlo Simulation of Backscattered and Secondary Electron
Profiles.
Ch. Eisenschmidt, U. Werner ....... . . . . . . . . . . . . . . . 125
An Electron Scattering Model Applied to the Determination of Film
Thicknesses Using Electron Probe Microanalysis.
H.-J. August ............................... 131
Calculation of Depth Distribution Functions for Characteristic and for
Continuous Radiation.
H.-J. August . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
A Method for In-Situ Calibration of Semiconductor Detectors.
J. Wernisch, A. Schonthaler, H.-J. August. . . . . . . . . . . . 147
VIII Contents
Background Anomalies in Electron Probe Microanalysis Caused by
Total Reflection.
W P. Rehbach, P. Karduck . . . . . . . . . . . . . . . . . . . . . . . 153
Automatic Analysis of Soft X-Ray Emission Spectra Obtained by
EPMA.
/. A. Slavic, J. /. Slavic, /. A. Grzetic, M. K. Pavicevic . . . . . . . . . 161
The Scanning Very-Low-Energy Electron Microscopy (SVLEEM).
/. MiUlerova, M. Lenc . . . . . . . . . . . . . . . . . . . . . . . 173
To the Backscattering Contrast in Scanning Auger Microscopy.
L. Frank. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179
Design Consideration Regarding the Use of an Accelerator on Mass
Spectrometer in Ion Microanalysis.
K. M. Subotic, M. K. Pavicevic .. . . . . . . . . . . . . . . . . . . . 187
Accurate Estimation of Uncertainties in Quantitative Electron Ener
gy-Loss Spectrometry.
J. J. Y. Van Puymbroeck, W. A. Jacob, P. J. M. Van Espen . . . . . . . 191
An EELS System for a TEM/STEM-Performance and Its Use in Mate
rials Science.
R. Schneider, W Rechner . . . . . . . . . . . . . . . . . . . . . .. 197
Quantitative X-Ray Microanalysis of Bio-Organic Bulk Specimens.
A. Boekestein . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 205
Quantitative Analysis of (Y203)x (ZrOJ1-x Films on Silicon by EPMA.
N. Ammann, A. Lubig, P. Karduck . . . . . . . . . . . . . . . . . . . 213
EPMA of Surface Oxide Films.
P. Willich, K. Schiffmann .. 221
Non-Destructive Determination of Ion-Implanted Impurity
Distribution in Silicon by EPMA.
A. P. Alexeyev. . . . . . . . . . . . . . 229
An Electron Spectroscopy Study of a-SiNx Films.
A. G. Fitzgerald, H. L. L. Watton, M. J. Rose. . .......... 235
Electron Probe Microanalysis of Glass Fiber Optics.
M. Kern, E. Perman, P. Pavli . . . . . . . . . 241
Quantitative Microanalysis of Low Concentrations of Carbon
III
Steels.
J. Ruste .............. . 247
Contents IX
Electron Configuration of the Valence-Conduction Band of the
Mineral Wustite.
D. M. Timotijevic, M. K. Pavicevic . .. 255
Structural Analysis of Silver Halide Cubic Microcrystals with
Epitaxial or Conversion Growths by STEM-EDX.
S. Wu, A. Van Daele, W Jacob, R. Gijbels, A. Verbeeck, R. De Keyzer 261
Characterization of the Bony Matrix of the Otic Capsule in Human
Fetuses by EPMA.
S. S. Montoro, F F Declau, P. J. Van Espen . . . . . . . . . . . . . . 269
Overview.
M. K. Pavicevic, A. Boekestein . ..................... 275
Mikrochim. Acta (1992) [Supp!.] 12: 1-17
© Springer-Verlag 1992
EPMA-A Versatile Technique for the
Characterization of Thin Films and Layered
Structures
Peter Willich
Fraunhofer-Institut fUr Schicht-und Oberflachentechnik, P.o. Box 540645,
D-W-2000 Hamburg 54, Federal Republic of Germany
Abstract. Electron probe microanalysis (EPMA) is presented as a quantitative
technique of near-surface chemical characterization. Three principle operation
modes are discussed: (1) "Thick" films (> 100 I1g/cm2, 0.2 11m for a density of
5 g/cm3) are studied by use of a sufficiently low electron energy. (2) The com
bined determination of film thickness and composition is applied to "thin" films
and multilayers « 250 I1g/cm2, 0.5 11m for a density of 5 g/cm3). Relatively fast
analysis at a single electron energy is possible under certain restrictions. (3) The
universal approach of non-destructive in-depth analysis is based on combining
experiments performed at different electron energies. The operation modes are
described with respect to experimental procedures, data reduction models, preci
sion, accuracy and the range of practical applications. EPMA is also related to
other techniques of thin film and surface analysis.
Key words: electron probe microanalysis (EPMA), thin films, multilayers, film
thickness, non-destructive in-depth analysis, ultralight elements.
For almost 40 years electron probe microanalysis has been developed as a powerful
tool for the local chemical characterization of solids. The majority of applications,
in combination with scanning electron microscopy, is directed to analysis with a
lateral resolution of about 111m, whereas the aspect of near-surface analysis is
frequently neglected. Although interesting attempts in this direction were started as
early as the beginning of the 1960s, as listed by Heinrich [IJ, these procedures and
models did not succeed as routine tools for the characterization of thin film samples.
This was due to the fact that none of them proved to be sufficiently general and
quantitative. A new era of EPMA applied to thin film materials started in 1984,
when Pouchou and Pichoir [2J presented a thin film correction model based on a
realistic description of $(pz) depth distribution functions. Moreover, Pouchou and
Pichoir proposed a general procedure for analysis of samples of which the composi
tion varied in depth. In the following years, similar thin film applications have been
discussed using completely different $(pz) data reduction models [3-5J, originally
developed to improve the accuracy of conventional "bulk" EPMA.
2 P. Willich
In addition to the development of general and sufficiently accurate correction
models, EPMA of thin films and layered structures has been stimulated by recent
instrumental and experimental improvements. This concerns the reliable operation
ofEPMA instruments at low electron energies, typically below 10 keY, the handling
of contamination phenomena [6], and, with respect to wavelength dispersive X-ray
spectrometry (WDS), the significantly improved sensitivity for the determination of
soft X-rays by use of synthetic multilayer monochromators. Quantitative EPMA
of ultralight elements (boron-oxygen), which play an important role in thin film
technology, has now reached a remarkable degree of precision and accuracy [7].
Thin film analysis has to be regarded as an essential part of thin film technology,
the importance of which is rapidly increasing in many fields of application. An ideal
technique of analysis should be applicable to a wide range of materials and layered
configurations, easy to operate, quantitative, and sufficiently local with respect to
lateral resolution and depth of analysis. From this point of view the recent develop
ments of EPMA have to be considered. This paper reviews, by examples of techno
logical interest, the various operation modes of EPMA applied to thin films and
stratified materials. The characteristics of EPMA are discussed in relation to the
features of other techniques frequently applied to thin film and surface analysis.
EPMA in Comparison with Other Techniques of Thin Film Analysis
Table 1 gives an overview of a number of techniques to carry out analysis of surfaces
and near-surface regions. The data of Table 1 are mainly drawn from a recent review
of Werner and Torrisi [8], supplemented by experience of our own laboratory. In
Table 1. Comparison of some techniques applied to local analysis of thin films and surfaces
Depth Lateral Depth Quantitative
Technique resolution resolution Elements LLD2 [JIg/g] profiling analysis!
XRF >5 JIm >5mm Z>9 >5 no <3%
EPMA-WDS 0.1-2 J.lm >0.5J.1m Z>3 >20 (limited) <5%
AES 1nm >0.1 J.lm Z>3 >1000 sputtering 10-20%
XPS 2nm >100 J.lm Z>2 >1000 sputtering 10-20%
RBS 2-20 nm >100 J.lm Z>5 >1000 non-destr. <5%
ERD 2-20 nm >100 J.lm hydrogen >1000 non-destr. <10%
SIMS 2nm >0.1 J.lm all <1 sputtering difficult
SNMS/SALI 2nm >1J.1m all >1 sputtering 5-20%
LAMMA >0.5 JIm >3 JIm all <1 no difficult
! Accuracy without matched standards
2 LLD = Lower limit of detection
Acronyms:
XRF X-ray fluorescence, EPMA-WDS electron probe microanalysis-wavelength dispersive
spectrometry,
AES Auger electron spectroscopy, XPS X-ray photoelectron spectroscopy,
RBS Rutherford backscattering spectrometry, ERD elastic recoil detection,
SIMS secondary ion mass spectrometry, SNMS secondary neutral mass spectroscopy,
SALI surface analysis by laser ionization, LAMMA laser microprobe mass analysis
