Electric‐field‐intensity‐modulated scattering as a thin‐film depth probe

• Published in: Journal of applied crystallography 2020-12, Vol.53 (6), p.1484-1492
• Main Authors: Dudenas, Peter J., Weber, Adam Z., Kusoglu, Ahmet
• Format: Article
• Language: English
• Subjects: Born approximation; distorted‐wave Born approximation; electric field intensity; Energy resolution; Film thickness; Grazing; grazing‐incidence X‐ray scattering; Incidence; Multilayers; Polymer films; Polymers; Refractivity; Scattering; Thin films
• ISSN: 1600-5767; 0021-8898; 1600-5767
• DOI: 10.1107/S1600576720013047

Grazing‐incidence X‐ray scattering is a common technique to elucidate nanostructural information for thin‐film samples, but depth‐resolving this nanostructure is difficult using a single or few images. An in situ method to extract film thickness, the index of refraction and depth information using scattering images taken across a range of incident angles is presented here. The technique is described within the multilayer distorted‐wave Born approximation and validated using two sets of polymer thin films. Angular divergence and energy resolution effects are considered, and implementation of the technique as a general beamline procedure is discussed. Electric‐field‐intensity‐modulated scattering is a general technique applicable to myriad materials and enables the acquisition of depth‐sensitive information in situ at any grazing‐incidence‐capable beamline. Grazing‐incidence X‐ray scattering is a common technique to elucidate nanostructural information for thin‐film samples, but depth‐resolving this nanostructure is difficult using a single or few images. An in situ method to extract the film thickness, the index of refraction and depth information using scattering images taken across a range of incident angles is presented.