Li-Ngee Ho

Properties of Phenolic-Based Ag-Filled Conductive Adhesive Affected by Different Coupling Agents

In this study, a phenolic-based Ag flake-filled electrically conductive adhesive (ECA) was investigated in terms of rheological, electrical, and mechanical properties. To clarify the effect of various Ag flake filler content and silane coupling agents on the characteristic of the ECA, rheological properties of the Ag flake-filled ECA paste, electrical resistivity, and shear strength of the cured ECA were investigated. Results showed that an increase of Ag flake content leads to an increase in both viscosity of the ECA paste and electrical conductivity of the as-cured ECA. Silane coupling agents-treated Ag flakes have a significant effect on the electrical resistivity and shear strength in the ECAs.

Electrical Properties of Pre-Alloyed Cu-P Containing Electrically Conductive Adhesive

In this study, a pre-alloyed Cu-P powder with a trace amount of P (0.002 at.%) was used as a metallic filler in a phenolic resin-based electrically conductive adhesive (ECA). The electrical property of the Cu-P-filled ECA was investigated for long-term stability and reliability by aging at high temperature exposure at 125°C and 85°C/85% RH for 1000 h, respectively. Results showed that the electrical resistivity of the Cu-P-filled ECA could be maintained consistently low after high temperature exposure at 125°C for 1000 h or aging at 85°C/85% RH for 1000 h, compared with the rapidly increased resistivity of Cu-filled ECA over time. A significantly low final resistivity at an order of magnitude of 10−4 Ω·cm could be maintained in Cu-P-filled ECA even after aging at 85°C/85% RH for 1000 h.

Properties of porous copper filled electrically conductive adhesives

In this study, three types of copper particles produced by wet chemical reduction method which include two different types of micron-size copper and a porous copper particles, were applied as metallic fillers in electrically conductive adhesive (ECA). Morphology of the Cu particles was observed by using scanning electron microscope (SEM). Properties of these three Cu filled ECAs were investigated and compared in terms of electrical and mechanical properties. Mechanical property of the ECA was evaluated through shear strength joint of the ECA with Cu specimens, and electrical property of the ECA was evaluated by using a standard four-point probe method. Significant difference could be found in the electrical percolation threshold of the ECAs prepared in this study. Lowest percolation filler content was observed in the porous Cu filled ECA whereas relatively high percolation filler content was found in the micron-size Cu filled ECAs.