Periodic Multilayers MoSi2/Si with a Large Number of Periods

Different approaches to decreasing mechanical stresses developed in MoSi₂/Si multilayers with increase of number of periods due to structural reconstruction in layers of amorphous silicon and nanocrystalline MoSi₂ were studied by scattering CuKα X-ray radiation at small and large angles, cross-sectional electron microscopy and micrometry of substrate sag. It was shown that effective relaxation of mechanical stresses in MoSi₂/Si multilayers is achieved by annealing them at ～320 °C during 1 hour, or by deposition of layers at substrate temperature ～320 °C, or by increasing sputtering gas pressure up to 7 × 10^—3 Torr in case of argon. Optimal conditions for deposition of MoSi₂/Si multilayers with periods N > 10³ and high reflectivity of X-rays with wavelengths 12.4—20.0 nm are: substrate temperature T_s = 220 °C, argon pressure P_Ar = 3 × 10^—3 Torr, layer deposition rate 1 nm/s.