METHOD AND APPARATUS FOR MATERIAL ANALYSIS

摘要

Method and apparatus for material analysis in which X-rays generated pursuant to incidence of an electron beam on the material are detected by a detector (24) which generates signals representative of X-ray intensity. A first single channel analyser (SCA-1) is connected to receive the signals from the detector (24) and to pass to an associated first counter (CTR-1) a count signal whenever the signal applied to the first single channel analyser is representative of an X-ray energy within a relatively narrow range of such energies. A second single channel analyser (BG-1) is also connected to receive the signals from the detector (24) and to pass to an associated second counter (B-1) a count signal whenever the signal applied to the second analyser (BG-1) is representative of an X-ray energy falling within a much broader range of such energies than the first-mentioned range. The first and second counters (CTR-1 and B-1) accumulate the count signals applied thereto. The count in the second counter (B-1) is compared by a comparator (C-1) with a pre-established count in a third counter (A-1) and when the count in the second counter (B-1) assumes the same value as the count in the third counter (A-1) the counts in the first and second counters (CTR-1 and B-1) are held. The so held count in the first counter (CTR-1) then itself represents a normalized ratio of X-ray energy within the narrow range to the X-ray energy for the energy spectrum represented by the broad range of energies. On the basis of this normalized ratio information as to the makeup of the material can be derived.