Reflectivity and resolution X-ray dispersive and reflective structures for carbon, beryllium and boron analysis

Claim 1

In a method for the wavelength dispersive spectroscopic analysis for a light metal chosen from the group consisting of beryllium and boron, comprising the steps of: providing a sample; direction a beam of X-rays at said sample, to cause the sample to emit fluorescent radiation X-rays; directing said emitted X-rays onto an X-ray dispersive structure and reflecting said X-rays from said X-ray dispersive structure to a detector; and detecting said reflected X-rays to perform the analysis; the improvement wherein said X-ray dispersive structure includes a plurality of layer pairs formed on one another, one layer of said layer pair being formed of B 4 C, the other layer of said layer pair being formed of vacuum deposited molybdenum, and said layer pairs having a d spacing of 35 to 200 Angstrom, whereby said layer pairs have X-ray dispersive properties over a predetermined first wavelength range of interest, and a maximum net peak to background ratio at a narrow second wavelength range of 55 to 130 Angstroms within said predetermined wavelength range of interest for the detection of beryllium and boron.