A Study of Low-Cost Sequential Electroplating Bumping Process and Its Metallurgical Behavior

Studies were conducted to validate from a metallurgical point of view whether a lower cost sequential plating approach to SnAg and SnAgCu (SAC) solder bumping is a suitable alternative to the conventional alloy plating process. A range of Ag content corresponding to typical bump applications was explored with respect to Ag diffusion and intermetallic compound (IMC) formation. Variables that can af...