Conference paper
Development of Ni-based multilayers for future focusing soft gamma ray telescopes
Ni-based multilayers are a possible solution to extend the upper energy range of hard X-ray focusing telescopes currently limited at ≈79:4 keV by the Pt-K absorption edge. In this study 10 bilayers multilayers with a constant bilayer thickness were coated with the DC magnetron sputtering facility at DTU Space, characterized at 8 keV using X-ray reectometry and fitted using the IMD software.
Ni/C multilayers were found to have a mean interface roughness ≈ 1:5 times lower than Ni/B4C multilayers. Reactive sputtering with ≈ 76% of Ar and ≈ 24% of N2 reduced the mean interface roughness by a factor of ≈ 1:7. It also increased the coating rate of C by a factor of ≈ 3:1 and lead to a coating process going ≈ 1:6 times faster.
Honeycomb collimation proved to limit the increase in mean interface roughness when the bilayer thickness increases at the price of a coating process going ≈ 1:9 times longer than with separator plates. Finally a Ni/C 150 bilayers depth-graded mutilayer was coated with reactive sputtering and honeycomb collimation and then characterized from 10 keV to 150 keV.
It showed 10% reectance up to 85 keV
Language: | English |
---|---|
Publisher: | SPIE - International Society for Optical Engineering |
Year: | 2015 |
Pages: | 96031D-96031D-11 |
Proceedings: | Optics for EUV, X-Ray, and Gamma-Ray Astronomy VII |
Series: | Proceedings of Spie - the International Society for Optical Engineering |
ISBN: | 1628417692 and 9781628417692 |
ISSN: | 1996756x and 0277786x |
Types: | Conference paper |
DOI: | 10.1117/12.2186814 |
ORCIDs: | Girou, David A. , Massahi, Sonny and Christensen, Finn E. |