Modeling Wafer Bending Effects on RDL Layer Reliability in a Multiple Die Package

Wafer bending effects on re-distribution layer (RDL) reliability in a multiple die package is examined using multiscale TCAD sub-modeling techniques. At the global scale, the wafer package with 200 dies and 3 RDL layers is analyzed with smear material representation. At the die scale, three dies from the center, middle, and edge of the package wafer are analyzed to examine the die location effect during wafer bending. At the RDL local scale, wafer bending and layout pattern effects on RDL reliability are examined. Between the scales, TCAD sub-modeling with buffer region technique is employed to extract upper scale solution as boundary constrains for lower scale analyses. The study also considers material effects with temperature dependent material properties and plastic deformation during thermal cycles.