In-situ X-ray tomographic imaging and controlled steering of microcracks in 3D nanopatterned structures

• Published in: Materials & design Vol. 221; p. 110946
• Main Authors: Kutukova, Kristina, Gluch, Jürgen, Kraatz, Matthias, Clausner, André, Zschech, Ehrenfried
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-09-2022; Elsevier
• Subjects: 3D morphology; Energy relase rate; Microcrack propagation and steering; Micromechanical test; X-ray computed tomograohy; X-ray microscopy; Micromechanical test; Microcrack propagation and steering; 3D morphology; X-ray computed tomograohy; X-ray microscopy; Energy relase rate
• ISSN: 0264-1275; 1873-4197
• DOI: 10.1016/j.matdes.2022.110946

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•A novel technique to monitor and control the microcracking process in specially designed 3D nanopatterned structures in real time is demonstrated on a technically relevant materials system, i.e. an on-chip interconnect stack. The three-dimensional details of the complicated physical failure mechanism are unveiled with high resolution.•The combination of X-ray microscopy and micromechanics and the ability to image microcracks in a model system with a hierarchically structured architecture is described.•The critical energy release rate at the crack tip is determined quantitatively in sub-100 nm regions.•A controlled microcrack steering into regions with high fracture toughness is demonstrated for an engineered hierarchical materials system.
An experimental approach to control the fracture behavior of 3D nanopatterned structures in real time and to describe the microcrack propagation in solids quantitatively is presented. The three-dimensional details of the complicated failure mechanism are unveiled with high resolution using a method that integrates a micro-scale fracture mechanics test into a nano X-ray computed tomography system, to allow in-situ 3D imaging of the kinetics of damage mechanisms in integrated circuits. With the unique combination of a miniaturized micro-mechanical experiment and high-resolution X-ray imaging, the critical energy release rate at the crack tip of materials is determined quantitatively in sub-100 nm dimension, which allows to reveal scale-dependent mechanical properties. The ability of controlled microcrack steering in engineered materials and structures into regions with high fracture toughness is demonstrated. This unique characterization capability promises broad applications for design and manufacturing of robust microchips in future technology nodes, and it is applicable to the study of a broad variety of 3D nanostructured material systems.