A thermal cycling reliability study of ultrasonically bonded copper wires

Arjmand, Elaheh; Agyakwa, Pearl A.; Corfield, Martin R.; Li, Jianfeng; Mouawad, Bassem; Mark Johnson, C.

Abstract

In this work we report on a reliability investigation regarding heavy copper wires ultrasonically bonded onto active braze copper substrates. The results obtained from both a non-destructive approach using 3D X-ray tomography and shear tests showed no discernible degradation or wear out from initial conditions to 2900 passive thermal cycles from − 55 to 125 °C. Instead, an apparent increase in shear strength is observed as the number of thermal cycles increases. Nanoindentation hardness investigations suggest the occurrence of cyclic hardening. Microstructural investigations of the interfacial morphologies before and after cycling and after shear testing are also presented and discussed.

Citation

Arjmand, E., Agyakwa, P. A., Corfield, M. R., Li, J., Mouawad, B., & Mark Johnson, C. (2016). A thermal cycling reliability study of ultrasonically bonded copper wires. Microelectronics Reliability, 59, https://doi.org/10.1016/j.microrel.2016.01.009

• Journal Article Type: Article
• Acceptance Date: Jan 16, 2016
• Online Publication Date: Jan 25, 2016
• Publication Date: Apr 1, 2016
• Deposit Date: Oct 3, 2016
• Publicly Available Date: Oct 3, 2016
• Journal: Microelectronics Reliability
• Print ISSN: 0026-2714
• Electronic ISSN: 0026-2714
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 59
• DOI: https://doi.org/10.1016/j.microrel.2016.01.009
• Keywords: Heavy copper wire bonding; Reliability; Power electronics; Passive thermal cycling; Hardness
• Public URL: https://nottingham-repository.worktribe.com/output/977208
• Publisher URL: http://www.sciencedirect.com/science/article/pii/S0026271416300099
• Contract Date: Oct 3, 2016