Electron probe microanalysis on electron microscope thin foils using thin standards

Abstract

Electron probe microanalysis, associated with electron microscopy, of thin foils of gold-silver alloys has been made using thin fods of pure elements as standards.Theoretical bases are discussed. Specimens and standards were prepared by vaporization in vacuum and their thickness accurately measured. The anomalous emission effect does not seem to introduce errors in these experiments.

The quantitative analysis of thin specimens: a review of progress from the Cliff‐Lorimer to the new ζ‐factor methods

“…The compositions determined via the ζ-factors superimpose well on the EPMA data over the thickness range relevant to this analysis. It should be noted that other attempts have been made to replace multielement-alloy standards with PE thin films (Philibert et al, 1970;Brown et al, 1981;King, 1985). These approaches are similar to the ζ-factor method as they all use the X-ray production rate in their definition, i.e.…”

“…In addition to the PE-film approaches, quantification procedures for thin specimens via bulk standards were also proposed (Philibert & Tixier, 1975;Thomas et al, 1984;Boon & Bastin, 2004). It is obviously much easier to prepare bulk standards but full, matrix-correction procedures were still required to determine the X-ray production rate and these procedures are more complicated and sophisticated than Eq.…”

Metal oxide structure investigated using a variety of light‐ and electron‐microscopical techniques*

“…It is impossible to determine the Fe-Cr ratio in thin protective oxide layers without film stripping because of interference from the underlying alloy. Thin films also have the advantage that calculations for probe microanalysis results are simplied (Philibert et al, 1970) though it is advisable to calibrate with reference to thin film standards as discrepancies in the ratio of X-ray counts have been found on comparing iron and chromium films about 1 pm thick with massive standards.…”

Optical properties of Ag-Cu alloys : evidence for d-virtual bound states on Cu impurities

“…(**) Equipe de Recherche associee au C.N.R.S. alloy composition by electron microprobe analysis with 1 % accuracy [11]. Homogeneous films could only be obtained by using very high deposition rates (flash evaporation) and by depositing the films on substrates held at low temperatures ( ~ 180 K) ; introduction of Ar in the vacuum chamber while the film was maintained at low temperature seemed to prevent atomic rearrangements leading to phaseseparation when bringing the samples back to room temperature for optical studies.…”

“…The main parameters Ed and L1 are determined with a few % accuracy, Wd less accurately; i;(0) and wp were often strongly correlated, and their values are more scattered. Table I gives the values of Ed, 11 and Wd for a few alloys, including the more concentrated one : the d-virtual bound states localized on Cu impurities in a Ag matrix are located at about Position with respect to the Fermi level Ed and half-width L1 of Cu d-virtual bound states in Ag, and coupling parameter for d-s transition Wd deduced from the optical absorption as e~~plained in the text for different Ag-rich alloys.…”