Residual Stress and Warpage Induced by Underfill Curing in a Chip Package
Application ID: 131061
Flip chip (FC) is a widely-used form of advanced semiconductor packaging, which yields small size, high interconnection density, and good signal transmission performance of the semiconductor device. In FC devices, the chip is placed face down and directly bonded to the substrate, or other carriers, using bumps. A polymer underfill, cured at high temperature, is used to fill the gap between bumps and substrate. In this way, the polymer protects the bump connections. However, due to shrinkage of the polymer and differences in thermal expansion of the different materials, the curing of the underfill may introduce residual stresses, which may cause an overall warpage of the package.
This model demonstrates the effects of underfill curing on the deformation during packaging of FC devices. Moreover, this model can provide a reference for simulating other processes related to polymer curing in semiconductor packaging, such as temporary bonding and EMC curing.
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however, additional products may be required to completely define and model it. Furthermore, this example may also be defined and modeled using components from the following product combinations:
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