AVS 45th International Symposium
    Applied Surface Science Division Thursday Sessions
       Session AS-ThP

Paper AS-ThP8
X-Ray Microanalysis Inverse Modeling@footnote 1@

Thursday, November 5, 1998, 5:30 pm, Room Hall A

Session: Aspects of Applied Surface Science Poster Session
Presenter: H.W. Wagner, Technische Universität Wien, Austria
Authors: H.W. Wagner, Technische Universität Wien, Austria
W.S.M. Werner, Technische Universität Wien, Austria
H. Störi, Technische Universität Wien, Austria
Correspondent: Click to Email
The typical electron interaction volume in electron microprobe analysis (EPMA) is in the order of several cubic microns. For a single spot measurement of a sample with complex geometry, the source distribution of characteristic x-ray signals within this volume cannot be determined, therefore making it impossible to gain information on the sample structure. A set of measurements performed under different conditions (e.g. beam energies, incidence angles) does contain structural information, however not in a readily available form. The present work describes an approach for the extraction of structural information from EPMA measurements. The inverse modeling method relies on an efficient way to compute the forward transformation, i.e. the calculation of a generated x-ray signal of a known structure and experimental setup, and the application of appropriate mathematical optimization techniques. The use of simulated annealing as optimization method turned out to be advantageous in this context. The presented approach can be applied to arbitrary 2-D structures and accounts for possible a priori information on the sample structure. @FootnoteText@ @footnote 1@ The authors wish to thank Digital Equipment Corp. for support of this work.