The effect of elevated temperatures on the structural stability of Mo - Si and MoSi₂ - Si X-ray multilayer mirrors was studied. Multilayers deposited by magnetron sputtering were annealed at temperatures ranging from 300 to 1300 K. A detailed picture of the thermally induced changes in the microstructure is obtained using several techniques including small- and large-angle X-ray scattering and transmission electron microscopy. The main causes of the degradation of Mo - Si mirrors is an interdiffusion mixing of silicon and molybdenum layers and a formation of MoSi₂ in both the hexagonal and tetragonal phases. The smoothening of interfaces in MoSi₂ - Si mirrors and increasing of their reflectance were observed after annealing at temperatures T < 800 K. The MoSi₂ - Si mirrors undergo a catastrophic degradation at T > 1000 K caused by a crystallization of amorphous Si and a recrystallization of hexagonal MoSi₂.

Date Published: 23 January 1995
PDF: 10 pages
Proc. SPIE 2453, X-Ray Optics and Surface Science, (23 January 1995); doi: 10.1117/12.200276

Published in SPIE Proceedings Vol. 2453:
X-Ray Optics and Surface Science
Alexander V. Vinogradov, Editor(s)