Electrical reliability of different alloying content on copper alloy fillers in electrically conductive adhesives

The thermal stability and electrical reliability of electrically conductive adhesives (ECAs) filled with Cu fillers alloying with different amount of Ag and Mg (0.2–1.5 at.%), respectively, were studied by comparing their electrical resistivity under high temperature exposure at 125 and 85 °C/85% RH for 1,000 h. Results showed that the Cu-Ag filled ECAs were superior to Cu-Mg filled ECAs in terms of thermal stability during aging under high temperature exposure and high humidity condition. A final resistivity on the order of 10⁻⁴ Ω.cm could be maintained for Cu-Ag filled ECAs after aging at 125 °C for 1,000 h. Cu-Mg filled ECAs showed relatively high electrical resistivity compared to Cu-Ag filled ECAs. Resistivity of Cu-Mg filled ECAs increased rapidly over time during high temperature exposure at 125 °C except for Cu-0.5 at.% Mg filled ECA which was thermally stable after 400 h of aging. The ECAs in this study could withstand high temperature exposure at 125 °C better than aging under a combination of elevated temperature and high humidity at 85 °C/85% RH.