| Zugriffsnummer | 56574 |
| Dokumenttyp | Konferenzartikel |
| Peer Review | mit Peer Review |
| Sprache | Englisch |
| Titel | Enabling next-generation multilayer technology for high-energy x-ray telescopes |
| Autor(in); Institution |
Massahi, S.; DTU Space, Kgs Lyngby, DENMARK
Paredes-Sanz, D.; DTU Space, Kgs Lyngby, DENMARK
Masteghin, M.; DTU Nanolab, Kgs Lyngby, DENMARK
Svendsen, S.; DTU Space, Kgs Lyngby, DENMARK
Ferreira, D. D. M.; DTU Space, Kgs Lyngby, DENMARK
Jegers, A. 'S; DTU Space, Kgs Lyngby, DENMARK
Skroblin, Dieter; 7.2, Röntgenmesstechnik mit Synchrotronstrahlung, PTB-Berlin
Cibik, Levent; 7.2, Röntgenmesstechnik mit Synchrotronstrahlung, PTB-Berlin
Fechner, Robert; 7.2, Röntgenmesstechnik mit Synchrotronstrahlung, PTB-Berlin
Gollwitzer, Christian; 7.2, Röntgenmesstechnik mit Synchrotronstrahlung, PTB-Berlin
Krumrey, Michael; 7.2, Röntgenmesstechnik mit Synchrotronstrahlung, PTB-Berlin
Christensen, F. E.; DTU Space, Kgs Lyngby, DENMARK
|
| Quelle/Jahr | Space Telescopes and Instrumentation 2026: Ultraviolet to Gamma Ray:(2026), 141464B-1 - 41464B-15 |
| Artikelnummer | 141464B |
| Schriftenreihe | Proceedings of SPIE: 14146 |
| Herausgeber(in) |
Nikzad, Shouleh; Jet Propulsion Lab., USA
|
| DOI | |
| Verlag | Bellingham, Wash.: SPIE |
| Konferenzangaben | Space Telescopes and Instrumentation 2026: Ultraviolet to Gamma Ray, Copenhagen, 5-10, Juli, 2026, Dänemark |
| Freie Schlagworte | X-ray optics ; Hard X-ray telescope optics ; Magnetron sputtering ; NiCu alloy thin films ; Depthgraded multilayers ; Interfacial roughness ; X-ray reflectometry ; Scanning transmission electron microscopy |
| Zusammenfassung | Extending the energy range of focusing X-ray telescopes beyond the 79 keV limit of NuSTAR requires multilayer coated mirrors with bilayer periods as small as 2 to 4 nm. This demands stringent interface quality which is challenging to achieve with pure nickel-based layers, due to their intrinsic polycrystalline growth. We present a nickel/copper (NiCu) alloy combined with nitrogen rich silicon (SiNx) multilayers deposited utilizing reactive magnetron sputtering with a novel split Ni/Cu target approach. A pure nickel target and a pure copper target each occupy 50% of the target area, enabling alloy deposition without a pre-alloyed target. Single-layer NiCu films exhibit average interfacial roughness of 0.53 nm under non-reactive and 0.51 nm under reactive (Ar+N2) conditions, with no dependence on film thickness over the 5 to 26 nm range investigated. In 10-period NiCu/SiNx multilayers, a critical NiCu layer thickness of ∼2.5 nm is identified: below this threshold the interface width reaches 0.75 nm, while above it the roughness stabilizes at ∼0.40 nm, approaching the substrate roughness of 0.34 nm. Four power-law depth-graded multilayers with 200 and 205 bilayer periods were fabricated and characterized by XRR at 8.048 keV and the energy dependence of the reflectance was investigated in the range from 3.4 to 10 keV at the four-crystal monochromator beamline in the PTB laboratory at the synchrotron radiation facility BESSY II. The cross-sectional HAADF-STEM, confirmed well-ordered structures across the full stack depth with interfacial roughness of σbot = 0.35 to 0.48 nm and σtop = 0.54 to 0.70 nm. EDS analysis reveals a Cu-enriched alloy composition (∼69 at. % and Cu, ∼31 at. % Ni), attributed to the differential sputtering yield of Cu and selective nitridation of the Ni target face. Simulated reflectance curves based on the best-fit parameters obtained from 8.048 keV X-ray reflectometry, demonstrate that the fabricated multilayers maintain reflectance above 95% up to ∼55 to 75 keV, with multilayer interference fringes remaining visible up to 200 keV, establishing NiCu alloy co-sputtering as a viable route to next-generation broadband hard X-ray telescope optics. |
| Themenbereich der Metrologie | Photometrie und Radiometrie |
Zitierung
Massahi, S., Paredes-Sanz, D., Masteghin, M., Svendsen, S., Ferreira, D. D. M., Jegers, A. '., Skroblin, D., Cibik, L., Fechner, R., Gollwitzer, C., Krumrey, M., & Christensen, F. E. (2026). Enabling next-generation multilayer technology for high-energy x-ray telescopes. Space Telescopes and Instrumentation 2026: Ultraviolet to Gamma Ray, Copenhagen, 5-10, Juli, 2026, Dänemark. https://doi.org/10.1117/12.3100629