The dependence of the layer structure and interfaces ofehyphen;beam deposited Mo/Si multilayers (ML) on growth conditions has been studied. The substrate temperature was varied over a range of 300ndash;600 K at deposition rates of 1 and 3 Aring;/s. The structure of the ML was determined using smallhyphen;angle xhyphen;ray scattering, largehyphen;angle xhyphen;ray scattering, and crosshyphen;sectional highhyphen;resolution electron microscopy. The variation of the normal incidence reflectivity was measured as a function of soft xhyphen;ray wavelength using synchrotron radiation. We found that the lateral extent of the Mo crystallites and the thickness and roughness of interlayers are a sensitive function of the substrate temperature. The morphology shows a lesser dependence on the deposition rate. The formation of the Mohyphen;onhyphen;Si interlayer is partially thermally activated with an activation energy of sim;0.2 eV. We propose that the rate limiting mechanism is surface diffusion during growth. At the optimal deposition conditions, of a substrate temperature of sim;525 K and a deposition rate of 1 Aring;/s, the ML structure was found to have a smoothness and maximum normal incidence reflectivity comparable to the best sputtered Mo/Si films.
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