Analysis of a failure in a molded package caused by electrochemical migration

Delamination of Plasticized Devices in Dynamic Service Environments

“…Lau et al [67] experimentally evaluated the characteristic lifetime of the rewiring layer and found that, at 0.0023 s after experiencing an impact, the maximum stresses of the package appeared in the four corners, with the bottommost rewiring layer undergoing the greatest stress and propensity to cracking. Similar stress distributions were also found in the study by Li et al [20] (Figure 10).…”

“…Lau et al [67] experimentally evaluated the characteristic lifetime of the rewiring layer and found that, at 0.0023 s after experiencing an impact, the maximum stresses of the package appeared in the four corners, with the bottommost rewiring layer undergoing the greatest stress and propensity to cracking. Similar stress distributions were also found in the study by Li et al [20] (Figure 10). In terms of external mechanical stress, Shih et al [69] found that when FCGBA assemblies are subjected to thermal cycling, the extra weight of the heat sink exerts additional mechanical stress on the solder joints, resulting in the solder balls at the corners of the uncovered FCBGA assemblies being more susceptible to more severe cracking.…”

“…However, to understand the generation mechanism of such delamination failures, we need to consider two main scenarios: (1) moisture damage, i.e., delamination caused by the intrusion of moisture; and (2) thermal stress damage, i.e., delamination triggered by thermal stresses due to temperature changes. [20]. Copyright 2021, Elsevier.…”

“…They can gradually absorb moisture in hot and humid working environments until they reach saturation. [20]. Copyright 2021, Elsevier.…”

“…( d ) Small cracks on the package body, next to a lead frame, are present on new components. Reproduced with permission [ 20 ]. Copyright 2021, Elsevier.…”