Reflecting X-rays is exactly what's needed for EUV litography, Hiroo Kinoshita had to fight quite a bit to have his research taken seriously back in the days but it's the foundation to how EUV lithography works.

Uhh.. can you be more specific? I think it's possible to reflect xrays https://en.wikipedia.org/wiki/X-ray_reflectivity https://x-ray-optics.de/index.php/en/physics/reflection