X-ray standing wave microscopy: Chemical microanalysis with atomic resolution

Abstract

We introduce a microprobe technique based on the x-ray standing wave method (XSW) demonstrating that structural analysis can be achieved with chemical sensitivity on a microscopic scale. We apply this XSW microscopy technique to study an epitaxially grown GaAs/Al0.1Ga0.9As/GaAs(001) heterostructure in cross section. We focus the x-ray beam by a refractive lens onto the cleaved sample and analyze the constituent elements within the 4 μm thick Al0.1Ga0.9As layer resolving the substitutional location of Al. The new micro-XSW technique will permit microscopic examinations of the structure of integrated semiconductor devices or microscopic crystalline grains with chemical sensitivity and structural resolution on the pm scale.