The present invention provides metal nanoparticles, containing copper core
and thin layer of precious metals enclosing the core to prevent
oxidization of copper, in which manufacturing the metal nanoparticles is
economical efficiency because of increased copper content and since such
metal nanoparticles contain a metal having high electrical conductivity
such as silver for a thin layer, they can form a wiring having better
conductivity than copper and there is little concern that silver
migration may occur.