Study on Preparation and Application of Nano-copper Powder for Power Semiconductor Device Packaging

Nano-copper powder is prepared by liquid phase reduction method in ethylene glycol solvent system. Nano-copper paste is prepared by mixing with organic carriers and subjected to pressureless sintering. The influence of different reducing agent systems on the particle size and morphology of nano-copper powder are studied. The sintering properties of the copper paste are tested by TEM, XRD and SEM. The results indicate that the synthesized product of using ethylene glycol as the reaction solvent and reducing agent is pure copper power and particle size from 100 nm to 200 nm at 160°C; The nano-copper paste can achieve metallurgical bonding at 300°C and the density of the sintered layer gradually increases with the sintering time prolonged, the porosity is gradually reduced, and the sintering of the nano-copper powder for 30 minutes is basically stable.