Evaluating IC-package interface delamination by considering moisture-induced molding-compound swelling

We have determined the influence of moisture soaking conditions on true adhesion strength measured by our previously developed method. The drop in true adhesion strength of a specimen that absorbed moisture at 50°C is about 50% less than that of a specimen at 85°C. This result suggests that the true adhesion strength depends on not only the moisture content but also the moisture absorption temperature. Therefore, we think that the general moisture condition (85°C/85%) causes more damage to plastic integrated circuit (IC) packages than that of moisture absorption at room temperature. We also evaluated interface delamination in a moisture-absorbed package by considering the swelling of the molding compound due to moisture absorption. The predicted interface delamination agrees well with the experimental data for moisture-soaked packages