Ion beam figuring of CVD silicon carbide mirrors

Details Ion beam figuring of CVD silicon carbide mirrors Ion beam figuring of CVD silicon carbide mirrors

Jun 2004

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2004esasp.554..691g&link_type=abstract

In: Proceedings of the 5th International Conference on Space Optics (ICSO 2004), 30 March - 2 April 2004, Toulouse, France. Ed.:

Physics

Optics

Space Optics, Mirrors

Scientific paper

Optical and structural elements made of silicon carbide are increasingly found in space instruments. Chemical vapor deposited silicon carbide (CVD-SiC) is used as a reflective coating on SiC optics in reason of its good behavior under polishing. The advantage of applying ion beam figuring (IBF) to CVD-SiC over other surface figure-improving techniques is discussed herein. The results of an IBF sequence performed at the Centre Spatial de Liège on a 100 mm CVD-SiC mirror are reported. The process allowed to reduce the mirror surface errors from 243 nm to 13 nm rms. Beside the surface figure, roughness is another critical feature to consider in order to preserve the optical quality of CVD-SiC. Thus, experiments focusing on the evolution of roughness were performed in various ion beam etching conditions. The roughness of samples etched at different depths down to 3 μm was determined with an optical profilometer. These measurements emphasize the importance of selecting the right combination of gas and beam energy to keep roughness at a low level. Kaufman-type ion sources are generally used to perform IBF but the performance of an end-Hall ion source in figuring CVD-SiC mirrors was also evaluated in this study. In order to do so, ion beam etching profiles obtained with the end-Hall source on CVD-SiC were measured and used as a basis for IBF simulations.

Affiliated with

Also associated with

No associations

Rating

Ion beam figuring of CVD silicon carbide mirrors does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Ion beam figuring of CVD silicon carbide mirrors, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ion beam figuring of CVD silicon carbide mirrors will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-893049