Nano solder paste is an innovative material for electronic packaging. Centered on nano silver or nano silver-copper supersaturated solid-solution particles, it forms a composite solder paste system with organic carriers, delivering high electrical conductivity and outstanding thermal stability. Benefiting from the nano-size effect of particles, the sintering temperature is greatly reduced. Dense structures are formed via metallurgical bonding, meeting the packaging requirements of high-temperature and high-power third-generation semiconductors devices(SiC/GaN).