X-ray reflectometer for single layer and multilayer coating characterization at 8 keV: An interlaboratory study

AnX-rayreflectometer (XRR) system has been developed at the Marshall Space Flight Center (MSFC) for characterizing various soft and hardX-ray opticcoatings. The XRR instrument generatesX-ray radiation using a high-output rotating anode source (RAS), operational over a voltage range of 5 –35 kV and a current range of 10–150 mA. Copper is used as the target material to produce anX-ray spectrum from which the Kα line at 8.048 keV is isolated for thereflectivity measurements. Five precision slits are mounted along theX-ray beam path to limit the extent of the beam at the sample and to adjust the resolution in the measurements. Agoniometer consisting of two precision rotary stages controls the positions of thecoating sample and theX-ray detector with respect to the beam. Thedetector itself is a high performance silicon driftdetector used to achieve high count rate efficiency to attain good statistics in thereflectivity measurement at larger grazing angles. TheX-rayreflectometer system design and capabilities are described in detail. Verification of the system is obtained through an interlaboratory study in whichreflectivity measurements of amultilayercoating made at MSFC are compared with those made at two external laboratories.

Source: Review of Scientific Instruments - October 28, 2016 Category: Physics Authors: Danielle N. Gurgew, David M. Broadway, Mikhail Gubarev, Brian D. Ramsey and Don A. Gregory Source Type: research