Thermal stress cracking is a significant mechanical failure mode in microelectronic components. This failure results from elevated stresses in components exposed to elevated temperatures due to the mismatch of thermal and mechanical properties of the constituent materials. The underlying mechanism responsible for these elevated stresses is not well understood. Therefore, we developed general mathematical and computational techniques for modeling the evolution of these stresses. As a test vehicle, we applied these techniques to thermal stress evolution in multilayer ceramic capacitors (MLCC). Thermal stress cracking has been implicated in significant, industry-wide problems associated with the cracking of these components. The model is used to solve for the transient development of thermal and mechanical gradients across the two spatial dimensions of the MLCC mid-plane. Material types with different thermal and mechanical properties and the interfaces between the material types are specifically included in the model. The stress field solutions are used to indicate when and where mechanical failure is expected to occur. The solutions of the model equations have been obtained using special partial differential equation solvers implemented on a CONVEX C120/220 supercomputer. The model is used to investigate the effects of MLCC termination geometry and material properties on the evolution of thermal stresses.

This content is only available via PDF.
You do not currently have access to this content.