With the development of grazing incidence telescopes, X-ray astronomy has experienced a rapid development in the last decades. Effective area plays an important role in telescopes performance. Except for increasing the geometric area, improving the reflectivity of coating mirror is a good way to increase effective area. Generally, the reflective coating is a smooth single layer of a heavy metal, such as gold, platinum, or iridium. We used a structure of bi-layer thin films with high reflectivity. The thin films were deposited on D263 glass substrate and the hard X-ray reflectance was measured. We compared the reflectivity of two samples, which coated with bare platinum and bi-layer structure, respectively. The fabricated structure is characterized and the estimated theoretical results of the reflectivity is calculated, reflectivity reached 95% and 91% in the energy region of 2 and 2.5 keV at the grazing incidence angle of 0.5°.
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