On the Change in the Reflectance of Мо(111) Mirrors after Exposure to D2–N2 Plasma

The effect of D2–N2 glow discharge plasma on the reflectivity of single-crystal Mo(111) mirrors is studied. The surface of each mirror is processed by mechanical polishing with diamond pastes to a roughness of hq = 5 nm. During polishing, abrasive particles are embedded in the surface layer of the mirror. Exposure to an ion fluence of 1.4 × 1024 m–2 leads to an increase in hq = 7 nm. After irradiation and the removal of a 30 nm-thick Mo layer the total reflection coefficient Rt in a 400–1000 nm region increases by 5–10% to a steady-state value (56–58)%. The increase in Rt may be caused by the preferential removal of carbon during the ion-sputtering process.