X-ray standing waves: a method for thin layered systems

Abstract

X-ray standing wave spectroscopy at grazing incidence (GI-XSW) is demonstrated to be a versatile method to characterize multilayer thin films and element distributions on a nanometre scale. In this work we present a measurement procedure and development of a computerized simulation tool to interpret measured intensities. Four different kinds of samples are investigated. First, thickness determination of a set of thin germanium layers on silicon ranging from 29 nm to 1 μm is presented, which demonstrates the wide dynamic range that is feasible and the limitations that occur. Second, analysis of a sample of gold clusters evaporated on an 80 nm polystyrene film on a silicon substrate is shown. Low contrast organic mono-, double or multilayers is the third kind of sample to be characterized by XSW. Finally, qualitative and quantitative characterization of a laser multilayer mirror utilizing XSW and a fast Fourier transform evaluation method are described. Measurement and simulation procedures for each kind of sample are outlined in this report as well as the possibilities and limits of this XSW method.