Simulation study of nanoparticle melting behavior for lead free nano solder application

Silver nanoparticle was used as model system for melting behavior study due to its wide application in the field of microelectronic packaging and the availability of force field. The Embedded Atom Method (EAM) was employed in conjunction with Molecular Dynamics (MD) simulations to investigate the effect of particle size and temperature ramping up rate on nano silver melting behavior. Silver spheres with diameter of 10 nm and 4 nm were prepared, and the temperature was raised up to 1200 K at a ramping up rate of 0.1K/ps and 1K/ps respectively. [010] projection and pair correlation function (PCF) were applied to study the structural evolution of silver particles as temperature is ramping up. The melting point was derived by observing the abrupt increase in potential energy. The effect of particle size and temperature ramping up rate on melting point was investigated. Surface melting behavior was studied by comparing the micro-structure of silver atoms located in core/shell regions.