Bonding of Cu wires by solid state sintering of Ag nanoparticles at low temperatures

Abstract

Solid state sintering of Ag nanoparticles was used to bond Cu wires to Cu foils at temperatures less than 250 o C. The Ag nanoparticles are coated with an organic shell to prevent sintering at room temperature. After annealing the nanoparticles at 200 o C, the decomposition of the organic shell was confirmed using TGA and Raman spectroscopy. The joint strength was measured by tensile shear tests, which shows that the joint strength increases as the bonding temperature increases. Metallic bond between Ag nanoparticles and Cu was achieved with no contamination. Bonds formed by our method, was confirmed to withstand temperatures higher than the bonding temperatures.

Low temperature joining of copper by Ag nanopaste: correlation of mechanical properties and process parameters

“…Previous publications only concern with joining of components in power electronics. Especially, joining with nanoparticles as a substitute for soldered joints, which tend to form cracks during thermal cycling, was investigated [14][15][16][17][18][19][20][21][22][23][24][25]. Nevertheless, there is a much greater potential for joining with nanoparticles.…”