Investigation of Creep Failure in Ag-4Pd Bonding Wire under Dynamic Mechanical Analysis Tests

• Published in: IEEE transactions on components, packaging, and manufacturing technology (2011) Vol. 13; no. 12; p. 1
• Main Authors: Chen, Chun-Hao, Chiang, Meng-Ting, Chuang, Tung-Han
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 01.12.2023; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Ag-alloy bonding wire; Arrhenius power-law creep; Bonding; Creep; Creep strength; Deformation; Diffusion rate; Dislocation mobility; Dynamic mechanical analysis; Equilibrium flow; failure analysis; Grain boundaries; Integrated circuits; Metal-metal bonding; Packaging; Physical properties; Power integrated circuits; Reliability; Steady state creep; Tensile stress; Wire; Wires
• ISSN: 2156-3950; 2156-3985
• DOI: 10.1109/TCPMT.2023.3336639

Ag-alloy wire is of particular interest in high power integrated circuits (ICs) due to its superior physical properties, but studies on creep failure in Ag-alloy wire are extremely sparse. This paper investigated the creep behavior of the widely used Ag-4Pd bonding wire at tensile stress levels of 20-80 MPa at constant temperature and in the temperature range of 300 °C to 400 °C at constant tensile stress. The steady-state creep flow behavior was analyzed through fitting of the Arrhenius power-law creep equation, and the rate-dependent process of creep deformation was found to be dislocation climb-controlled. The activation energy of creep in Ag-4Pd bonding wire is 133.86 kJ/mol within this temperature range, suggesting that fast diffusion paths could be involved. Results of cross-sectional analysis of the brittle fractured wire correlate with the kinetic analysis from a phenomenological point of view, indicating diffusion paths through grain boundaries.