Effect of current load on corrosion induced tin whisker growth from SnAgCu solder alloys

The effect of current load was investigated on corrosion induced tin whisker growth from SnAgCu (SAC) solder alloys. Three alloys were studied: two low Ag content micro-alloyed SAC and the widely used SAC305. The solder joints were loaded with six different DC current levels between 0 and 1.5A and they were aged in corrosive environment (85 °C/85RH%) for 3000 h. The morphology of the whiskers and the micro-structural changes of the solder joints were examined by scanning electron microscope. It was shown that the current load can decrease the corrosion of the solder joints and consequentially it can decrease whiskering as well.