Electromigration time to failure of SnAgCuNi solder joints

Electromigration time to failure and electrical resistivity of 95.5%Sn-1.5%Ag-0.5%Cu-0.03W%Ni microelectronics solder joints have been investigated experimentally. A Black-type electromigration time to failure equation is developed to describe the time to failure versus current density and temperature. It is observed that resistance of a solder joint is not just a function of the temperature but also a function of the current density. The activation energy over the range of 83-174 °C is measured to be 0.77±0.12 eV, and the current density exponent is found to be (8.60±1.65). It is also shown that the most commonly used Black's electromigration time to failure equation cannot be used for solder joints.