Inhibition of Silver Electrolytic Migration in Ag-Alloy Bonding Wires

Abstract:

Ion migration in Ag-alloy bonding wires was evaluated with water drop tests. The results indicated that water must be present between the wire couple for Ag electrolytic migration to occur. The addition of 1.5 to 4.5% Pd decreased the ion migration rate. Further alloying with about 8% Au enhanced this effect. It seems that the addition of Ni and Pt in Ag-alloy wires does not influence Ag-ion migration. Ag-alloy wires sealed with silicone gel and stressed in air and in distilled water revealed no dendrites after more than 1,000 hr. The ion migration in Ag-alloy bonding wires can be completely inhibited by a suitable encapsulation process with an appropriate molding compound.

• Periodical: Materials Science Forum (Volume 863)
• Pages: 95-101
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.863.95
• Online since: August 2016
• Authors: Chien Hsun Chuang*, Yan Cheng Lin, Yu Zhen He, Chih Hsin Tsai, Jun Der Lee, Shang Chih Wang, Hsing Hua Tsai
• Keywords: Ag Ion Migration, Ag-Alloy Bonding Wires, Silicone Gel Sealing, Water Drop Test

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