SOPRALAB has developed a new approach by combining two non destructive characterization techniques on the same instrument: Spectroscopic Ellipsometry (SE) and Grazing X-Ray Reflectometry (GXR). GXR is a powerful technique to measure the absolute thickness without an a-priori structural modelling of a multi-layer stack. GXR applies to any type of material: semiconductor, metallic, dielectric, organic.
GXR and SE measurement can be performed quasi-simultaneously at exactly the same sample location. Analysis of complementary data from both techniques with the same physical model leads to unprecedented accuracy in measurement results.

Grazing X-Ray Reflectometry (GXR) is certainly the technique of choice for absolute thickness measurement of new materials. At this energy, every material displays the same refractive indices (n being 1 and k being 0), simplifying considerably the structural model for data analysis. In case of complex multi-layers, accurate information can be obtained on the periodicity of stacks as well as on the interlayer structures.

SE combined GXR is the winning choice for the following applications: High K dielectrics (ZrO2, nitrided oxides), Thin ONO layers, Thin optical coatings, Si and SiGe thin epitaxial structures, thin metallic and organic layers, coatings for micro-lithography.