Mechanical reliability challenges for MEMS packages: Capping

This paper presents our effort to predict reliability problems for MEMS packages. MEMS devices are vulnerable to the external loads subjected to it. As such, MEMS devices need to be protected. Protections can be generated by capping the device: a piece of silicon is placed on top of it to create a cavity above it. Parametric finite element models are combined with dedicated verification experiments to address the reliability of four different capping concepts. The results gain a better understanding of MEMS capping issues, with failure modes as cavity deflection, cap fractures, and moisture penetration.