Effects of Grain Size on the Ag Dissolution and Ion Migration of Ag-4Pd Alloy Wires
Journal
Journal of Electronic Materials
Journal Volume
50
Journal Issue
10
Pages
5955-5964
Date Issued
2021
Author(s)
Abstract
Ion migration and corrosion behavior in Ag-4Pd alloy wires with fine and coarse grains in the outer regions were evaluated with water drop tests. The results from the in situ observations and measurements of Ag ion migration in both Ag-4Pd bonding wires indicated that the fine-grained wire had much shorter times of dendrite contact and short circuit than those of coarse-grained wire for various wire spaces. It was obvious that grain refinement in Ag-4Pd alloy wires accelerated the ion migration of Ag-4Pd alloy wires. Electrochemical polarization tests confirmed that the passive film on fine-grained Ag-4Pd wire was easily broken down, leading to a higher Ag dissolution tendency than that of coarse-grained wire. Although an annealing twin-rich Ag-4Pd alloy wire was shown to enhance the thermal stability of the grain structure and mechanical properties, the large number of twins had no influence on the formation of Ag dendrites on the cathode and Ag2O oxide on the anode of the coarse-grained Ag-4Pd wire couple during ion migration. ? 2021, The Minerals, Metals & Materials Society.
Subjects
Ag dissolution
Ag ion migration
Ag-4Pd alloy wires
annealing twins
grain refining
Binary alloys
Corrosive effects
Dissolution
Electrodes
Grain refinement
Grain size and shape
Ions
Silicon alloys
Silver alloys
Silver oxides
Thermodynamic stability
Wire
Ag dissolutions
Annealing twins
Coarse grains
Coarse-grained
Corrosion behavior
Electrochemical polarization test
In-situ observations
Passive films
Palladium alloys
SDGs
Type
journal article