Diffuse scattering sheets in reciprocal space corresponding to Kiessig fringes for x-ray multilayers

摘要

Synchrotron bending magnet radiation at the Advanced Photon Source was used to measure x-ray diffuse scattering of tungsten/carbon multilayers having period of 28 A. Scattering not only near the first Bragg sheet in reciprocal space, but also near sheets corresponding to Kiessig fringes was simulated in the Born approximation. Full roughness propagation starting with the substrate was used in the simulation. We conclude that the differential equation that describes the kinetic roughening during sputtering is second order, i.e., the Langevin equation. For thermal-diffusion-related kinetic roughening either a third-or fourth-order equation should apply, and we conclude that thermal mechanisms for kinetic roughening need not be invoked.