Study on Fabrication of Ni mirror chip for space X-ray telescopes utilizing LIGA process

We are developing novel ultra light-weight and high-resolution X-ray micro pore optics for space X-ray telescopes. Ni mirror chip for focusing and detecting X-rays is fabricated utilizing LIGA process (SR lithography and electroforming). In this time, in order to improve the detection efficiency of X-rays, fabrication process is improved. Especially, it keeps by liquid immersion from development process to electroforming process, collapse of the structure cased by the surface tension during dryness after development is prevented. Therefore, pitch width of Ni structure could be made narrow, and it succeeded in making large usable area of mirrors required for improvement in condensing efficiency of X-rays. Moreover, it is thought that still narrower pitch width and high structure height are realizable by using this liquid immersion process.