Impact of Low Temperature Solder on Electronic Package Dynamic Warpage Behavior and Requirement

Low temperature solder (LTS) adoption has increased over the years with the primary focus on reducing energy consumption. The fundamentals of dynamic warpage are well established in SMT industry, but there is minimal literature on the application of low temperature solders, specifically for SAC BGA with low temperature solder paste. iNEMI has conducted a wide range of dynamic warpage characterization of different electronic package types, namely package on package, fine pitch BGA, large FCBGA package with and without lids, and a wide selection of PBGA packages. The database generated has been reviewed to understand the impact of low temperature solder on dynamic warpage considerations which avoids the typical maximum peak and valley warpage present at higher reflow temperatures. Additional consideration should be given to the rate and magnitude of contour change during LTS solidification phase that can induce a solder hot tear defect. It was found that mostly the PBGA and FCBGA package require greater attention and optimization for LTS adoption.