Applicability of focused Ion beam (FIB) milling with gallium, neon, and xenon to the fracture toughness characterization of gold thin films

• Published in: Journal of materials research Vol. 36; no. 12; pp. 2505 - 2514
• Main Authors: Preiß, Eva I., Merle, Benoit, Xiao, Yuan, Gannott, Florentina, Liebig, Jan P., Wheeler, Jeffrey M., Göken, Mathias
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 28.06.2021; Springer Nature B.V
• Subjects: Applied and Technical Physics; Biomaterials; Chemistry and Materials Science; Crack initiation; Fracture toughness; Gallium; Gold; Grain boundaries; Inorganic Chemistry; Ion beams; Materials Engineering; Materials research; Materials Science; Mechanical properties; Nanotechnology; Neon; Thin films; Xenon
• ISSN: 0884-2914; 2044-5326
• DOI: 10.1557/s43578-020-00045-w

Focused ion beam (FIB) milling is an increasingly popular technique for fabricating micro-sized samples for nanomechanical characterization. Previous investigations have cautioned that exposure to a gallium ion beam can significantly alter the mechanical behavior of materials. In the present study, the effects of gallium, neon, and xenon ions are scrutinized. We demonstrate that fracture toughness measurements on freestanding gold thin films are unaffected by the choice of the ion species and milling parameters. This is likely because the crack initiation is controlled by the local microstructure and grain boundaries at the notch, rather than by the damaged area introduced by FIB milling. Additionally, gold is not susceptible to chemical embrittlement by common FIB ion species. This confirms the validity of microscale fracture measurements based on similar experimental designs. Graphical abstract