Surfactant-Free Synthesis of Copper Particles for Electrically Conductive Adhesive Applications

In this study, a simple one-step microwave-assisted method was developed to synthesize Cu and Cu-Ag particles for application in electrically conductive adhesive (ECA). The particle size of the obtained Cu particles was about 1 mu m to 3 mu m, whereas Cu-Ag particles were in the range of 0.1 mu m to 1.0 mu m. ECA samples were cured at 175A degrees C for 1 h. Results revealed that the as-cured ECAs showed significant differences in electrical resistivity. The resistivity of Cu-filled ECA was on the order of 10(-5) a"broken vertical bar cm, which was lower than the Cu-Ag-filled ECAs with resistivity on the order of 10(-3) a"broken vertical bar cm. The thermal stability of the ECAs was studied under high-temperature exposure at 125A degrees C for 1000 h. Results showed that Cu-filled ECA was thermally stable for 1000 h of aging, whereas Cu-Ag-filled ECAs were thermally stable for aging time above 100 h.