Transient thermal analysis as measurement method for IC package structural integrity |
Left: log-derivative plot of an Innolot sample at different temperature cycles (a); cross-section of the Innolot sample after 1000 TST cycles (b). Right: log-derivative plot of an SAC sample at different temperature cycles; (c) cross-section of the SAC sample after 1000 TST (d). The peak increase due to the crack in the solder joint is visible in the right figures [(c) and (d)]. |