Synthesis of highly antioxidant and low-temperature sintering Cu-Ag core-shell submicro-particles for high-power density electronic packaging

The highly antioxidant Cu-Ag core-shell submicro-particles (Cu@Ag particles) were synthesized by two steps including replacement reaction and chemical reduction deposition. The Cu submicro-particles with fine size and dispersion were purchased as cores. Glycol was used as reaction solvent and acted as the reductant at high temperature. The results indicate that Cu@Ag particles with complete, uniform and dense Ag-shells (about 100 nm thickness) were synthesized successfully during reaction at 9 degrees C for 40 min and 150 degrees C for 20 min subsequently, with formic acid added. What's more, the nanostructure on surface of the Ag-shell made the low-temperature sintering possible. Finally, Cu-Cu joints with high shear strength of 97.86 MPa were obtained with Cu@Ag particles by pressure sintering (250 degrees C for 15 min under 10 MPa) in atmosphere. (C) 2021 Published by Elsevier B.V.

Automated summary

The study successfully synthesized highly antioxidant Cu@Ag particles with complete, uniform and dense Ag shells, achieving high-strength Cu-Cu joints through low-temperature sintering.