Quantifying gold dissolution and intermetallic growth in Au–In systems: Insights into microstructure evolution
Journal
Journal of Alloys and Compounds
Journal Volume
1066
Start Page
188276
ISSN
09258388
Date Issued
2026-05-15
Author(s)
Chang, Chih-Chia Bill
Abstract
The Au–In system is of great interest for electronic bonding applications. To predict the resulting structure under known process conditions, it is essential to quantify the interfacial reactions between gold and indium. In this study, we measured the dissolution rate of gold in large-volume molten indium at various temperatures and fitted the data to an Arrhenius-type equation. The interdiffusion zone between a molten indium solder ball and a gold substrate was characterized, and the growth kinetics of each intermetallic compound (IMC) were described using power laws. Semi-infinite bulk couples were fabricated to represent aging behavior and observe the microstructure evolution. A distinct two-phase zone consisting of AgIn2 and In was confirmed. The growth of the major IMC, AuIn2, was well described by a mixed-kinetics model.
Subjects
Diffusion
Dissolution
Electronic packaging
Gold
Indium
Interfacial reaction
Intermetallic compound growth
Publisher
Elsevier Ltd
Type
journal article