The formation and evolution of intermetallic compounds formed between Sn–Ag–Zn–In lead-free solder and Ni/Cu substrate

• Published in: Journal of materials science. Materials in electronics 2009-07, Vol.20 (7), p.675-679
• Main Authors: Xu, R. L., Liu, Y. C., Han, Y. J., Wei, C., Wang, X., Yu, L. M.
• Format: Article
• Language: English
• Subjects: Applied sciences; Brazing. Soldering; Characterization and Evaluation of Materials; Chemistry and Materials Science; Condensed matter: structure, mechanical and thermal properties; Design. Technologies. Operation analysis. Testing; Electronics; Exact sciences and technology; Integrated circuits; Intermetallic compounds; Joining, thermal cutting: metallurgical aspects; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Materials Science; Metals. Metallurgy; Optical and Electronic Materials; Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties)
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-008-9785-z

The formation and evolution of intermetallic compounds (IMCs) layer between the Sn–3.7Ag–1.0–In–0.9Zn lead-free solder and Ni/Cu substrate were investigated for different reflow time. The morphology and thickness of the IMCs layer formed at the interface varies apparently with increasing the reflow time. At the early reflow stage, a thin continuous Ni 3 Sn 4 dissolved with small amount of Cu is observed. As the reflow time going on, a thick Sn–Ni–Cu ternary intermediate compound layer is formed at the interface after the plated Ni layer is consumed totally. When the reflow time is long enough, a final Cu 6 Sn 5 IMC layer dissolved with minor Ni will be formed. The IMCs layer grows very slowly until the plated Ni layer was completely consumed. Once the plated Ni layer disappears, the corresponding growth rate of the IMC layer increases apparently.