3D nano-metrology with X-ray fluorescence and scattering techniques

PTB researchers develop new algorithm for the fast reconstruction of atom distributions in 3D nanostructured surfaces

Simulation of GIXRF maps for inhomogeneous distribution offluorescent atoms within the lamellar grating structure. From (a) to (c): sketch of the structure; the green box depicts the localization of the dopant atoms. From (a‘) to (c‘): corresponding GIXRF maps. Credit © PTB

Over the last years, PTB has developed a new method for atom-specific reconstruction of periodically nanostructured surfaces. Recent studies have shown experimentally that it is possible to reconstruct and identify the spatial distribution of different atomic species in nano-components using X-ray fluorescence radiation. These techniques could become a powerful tool in the development and manufacture of nanostructures.

A new mathematical model for the simulation of X-ray fluorescence intensity at grazing incidence of periodic 3D nanopattern structures was developed in the working groups 7.14 (EUV-Nanometrology), 7.24 (X-ray Spectrometry) and 8.41 (Modelling and Simulation) in collaboration with the University of Twente and the Kurchatov Institute. The new algorithm can be applied in general for light-matter interactions of layered systems and nanostructures. It is more than one magnitude faster than conventional FEM solutions with similar precision and accuracy. The development of the simulation algorithm is a considerable step towards the application of high precision real-time measurements that are suitable for inline metrology needed for the control of flexible manufacturing processes. Moreover, the significant speed up of computations enables the determination of reliable uncertainties based on Bayesian approaches which opens the possibility for the development of hybrid metrology techniques to improve PTB’s measurement capabilities even further

Publication:

A semi-analytical approach for the characterization of ordered 3D nanostructures using grazing-incidence X-ray fluorescence, Nikolaev, K. V., Soltwisch, V., Hönicke, P., Scholze, F., de la Rie, J., Yakunin, S. N., Makhotkin, I. A., van de Kruijs, R. W. E. & Bijkerk, F. (2020). J. Synchrotron Rad. 27

Contact:

Physikalisch-Technische Bundesanstalt

Dr. Sebastian Heidenreich
Working group 8.41: Modelling and Simulation
Phone: +49 30 3481-7726
Email: sebastian.heidenreich(at)ptb.de

Victor Soltwisch
Working group 7.14: EUV-Nanometrology
Phone: +49 30 3481-7129
Email: victor.soltwisch(at)ptb.de

Philipp Hönicke
Working group 7.24: X-ray Spectrometry
Phone: +49 30 3481-7174
Email: philipp.hoenicke(at)ptb.de

www.ptb.de