Ae. Yakshin et al., Determination of the layered structure in Mo/Si multilayers by grazing incidence X-ray reflectometry, PHYSICA B, 283(1-3), 2000, pp. 143-148
The formation of intermediate layers was investigated in Mo/Si multilayers
produced by e-beam evaporation and ion-beam smoothening. A model of a four-
layer step profile structure of the multilayer period was applied successfu
lly to account for grazing incidence X-ray reflectivity of the structures.
We have used a special method to determine the multilayer period compositio
n, namely the use of a laterally graded multilayer of which only the thickn
ess of the spacer layer was varied. The well-known modulation of the Bragg
peak intensities of 0.154 nm X-rays was then used to determine the thicknes
s and the composition of the silicides formed at the boundaries. The impact
of the polishing conditions on the thickness and composition of the interm
ediate layers was investigated. The study allowed optimization of the compo
sition of Mo/Si multilayer for use at near-normal incidence in the 12.5-15
nm wavelength area for Extreme UV Lithography. (C) 2000 Elsevier Science B.
V. All rights reserved.