Effect of Ni, Zn, Au, Sb and In on the Suppression of the Cu3Sn Phase in Sn-10 wt.%Cu Alloys

• Published in: Journal of electronic materials Vol. 50; no. 3; pp. 881 - 892
• Main Authors: Mehreen, Syeda U., Nogita, Kazuhiro, McDonald, Stuart D., Yasuda, Hideyuki, StJohn, David H.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-03-2021; Springer Nature B.V
• Subjects: Alloying elements; Alloys; Antimony; Characterization and Evaluation of Materials; Chemistry and Materials Science; Circuit reliability; Circuits; Copper; Copper base alloys; Electronic assemblies; Electronic packaging; Electronics and Microelectronics; Emerging Interconnection Technology; Instrumentation; Interconnect; Lead free; Materials Science; Microstructural analysis; Microstructure; Nickel; Optical and Electronic Materials; Pb-free Solder; Radiography; Silver; Solders; Solid State Physics; Solidification; Synchrotron radiation; Synchrotrons; Tin; Tin base alloys; TMS2020 Advanced Microelectronic Packaging; TMS2020 Microelectronic Packaging; Sn-Cu solders; Cu; Sn; peritectic alloy; solidification; Pb-free solders
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-020-08709-3

Since manufacturing is transitioning into Pb-free solder development for electronic assembly and packaging, consumer demands for more compact electronics have increased the importance of reliability issues brought about by the increased density of circuitry. Therefore, the role of alloying elements that can be added to common Pb-free solders such as Sn-Cu or Sn-Ag-Cu alloys in enhancing the properties and performance of the solder becomes important. Microstructural analysis along with direct observation in situ synchrotron radiography were used to study the effect of Ni, Zn, Au, In and Sb on the development of phases in Sn-10 wt.%Cu (Sn-10Cu). It was found that adding Ni and Zn to a Sn-10Cu alloy had the greatest impact on the microstructure with the Cu
3
Sn phase completely absent after these additions were made. Additions of Au and In also resulted in a reduction in the amount of Cu
3
Sn; however, the effect was not as pronounced. Removing the Cu
3
Sn phase from Sn-Cu Pb-free solder alloys is a possible approach for the design of more desirable microstructures that translate to better performance in modern electronic packaging.