Comparative efficiency of natural crystals and multilayers as dispersing devices in the copper L(2,3) range.

Recent sputtering techniques have been used to produce layered synthetic microstructures (LSMs) as dispersing devices for varied applications in x-ray optics and spectroscopy. These analyzers, specially suited for synchrotron radiation, have been mounted in a two-parallel crystal monochromator. In this paper we show the first experimental results obtained with beryl crystals and multilayers for analyzing x-ray spectral distributions transmitted through screens or reflected on mirrors of copper near the L(2) and L(3) absorption edges. The significance of these findings is discussed in terms of comparison with natural and synthetic crystals and of designing a useful dispersing device for x-ray spectroscopy.

Characterization of layered synthetic microstructure by transmission electron microscopy and diffraction.

Transmission electron diffraction patterns related to the cross section of layered synthetic microstructures (LSM's) are obtained. By depositing the multilayers onto (111) orientation silicon single-crystal substrates, it is possible to obtain on the same plate both the LSM diffraction pattern and a calibrated one and thus to measure the LSM mean period accurately. Results concerning tungsten-carbon LSM's are presented.