Coating process parameter influence on thin films for the ATHENA x-ray optics

Space Telescopes and Instrumentation: Ultraviolet to Gamma Ray, pp. 203

Abstract

The thin film deposition technology for fabrication of the mirror optics for the Advanced Telescope for HighEnergy Astrophysics (ATHENA) has been established. Numerous coating process parameters impact the quality of the thin films. Defining a margin within the coating process parameter space, where the deposited thin film performs similar in X-ray reflectivity is key to avoid unforeseen risks within the coating process for the ATHENA flight optics production. In this work, we investigate the coating process parameter influence on the thin film properties with a focus on micro roughness, deposition rate and residual film stress when deposited under various process conditions. The thin films were produced by varying the following three coating process parameters: discharge power, discharge voltage and working gas pressure. The thin films were characterized using X–ray reflectometry at 3.4–10.0 keV. A main result of this work is that the residual stress of single layer iridium and boron carbide films can be reduced by a factor of approximately two, by increasing the working gas pressure while maintaining a high film quality.

Authors 17

1. Sonny Massahi

   DTU Space

   Affiliation as printed

   DTU Space (Denmark)

2. Desirée Della Monica Ferreira

   DTU Space

   Affiliation as printed

   DTU Space (Denmark)

3. Finn E. Christensen

   DTU Space

   Affiliation as printed

   DTU Space (Denmark)

4. Sara Svendsen

   DTU Space

   Affiliation as printed

   DTU Space (Denmark)

5. Nis C. Gellert

   DTU Space

   Affiliation as printed

   DTU Space (Denmark)

6. Arne S. Jegers

   DTU Space

   Affiliation as printed

   DTU Space (Denmark)

7. Maximilien J. Collon Aachen cosine Research BV

   Cosine (Netherlands)

   Affiliation as printed

   cosine Research BV , Warmonderweg 14 , 2171 AH Sassenheim , The Netherlands

   cosine Research BV, Warmonderweg 14, 2171 AH Sassenheim, The Netherlands

8. Boris Landgraf Aachen Cosine measurement systems

   Cosine (Netherlands)

   Affiliation as printed

   Cosine Measurement Systems (Netherlands)

9. Aniket Thete Aachen Cosine measurement systems

   Cosine (Netherlands)

   Affiliation as printed

   Cosine Measurement Systems (Netherlands)

10. Ivo Ferreira

    European Space Agency

    Affiliation as printed

    European Space Agency (Netherlands)

11. Marcos Bavdaz

    European Space Agency

    Affiliation as printed

    European Space Agency (Netherlands)

12. Brian Shortt

    European Space Agency

    Affiliation as printed

    European Space Agency (Netherlands)

13. Waldemar Schönberger

    Von Ardenne (Germany)

    Affiliation as printed

    VON ARDENNE GmbH (Germany)

14. Axel Langer

    Von Ardenne (Germany)

    Affiliation as printed

    VON ARDENNE GmbH (Germany)

15. Michael K. Krumrey

    Physikalisch-Technische Bundesanstalt

    Affiliation as printed

    Physikalisch-Technische Bundesanstalt (Germany)

16. Christian Gollwitzer

    Physikalisch-Technische Bundesanstalt

    Affiliation as printed

    Physikalisch-Technische Bundesanstalt (Germany)

17. Evelyn Handick

    Physikalisch-Technische Bundesanstalt

    Affiliation as printed

    Physikalisch-Technische Bundesanstalt (Germany)