Ductile Au4Al intermetallic compound with crack resistance. (September 2019)

• Record Type: Journal Article
• Authors: Yang, Haokun; Wang, Yuejiao; Zhang, Hongti; Lu, Jian; Lu, Yang
• Is Part Of: Intermetallics. Volume 112(2019:Sep.)
• Publication Date: 2019-09
• Subjects: Intermetallics -- Focused ion beam machining -- Mechanical testing -- In situ testing -- Bonding -- Micromechanics; Intermetallic compounds -- Metallography -- Periodicals; Metallic glasses -- Periodicals; Composés intermétalliques -- Métallographie -- Périodiques; 669.94
• DOI: 10.1016/j.intermet.2019.106555
• Languages: English
• ISSNs: 0966-9795

Abstract

Abstract: The Au–Al intermetallic compounds (IMCs) were commonly regarded as brittle within wire bonding interfaces. Here the in-situ micro-pillar compression tests of Au4 Al IMCs were carried out to verify their intrinsic mechanical property. The result clearly shows that, surprisingly, the Au4 Al IMC is ductile, while the yield stress appeared to be about 1 GPa. Furthermore, upon the compression tests of Au4 Al IMC micro-pillars with initial crack, no brittle fracture was observed; instead, the plastic deformation of Au4 Al was shown via shear band. This work suggests that pristine Au4 Al IMC is ductile and crack-resistant, which provides new insights for wire bonding process and technology. Graphical abstract: Image 1 Highlights: The in-situ compression test confirms that the Au4Al intermetallic compound is both ductile and strong. The Au4 Al intermetallic compound has the capability to prevent crack propagation during the compression test. Au-rich Au–Al intermetallic compounds are proved to be ductile and crack-resistance.