Lifetime estimation of moems devices

Generally, microelectro mechanical systems (MOEMS) devices require encapsulation for protecting their fragile and tiny inner components in a hermetically sealed cavity. Cavity hermeticity can be critical to the device performance and plays a vital role with respect to reliability and long-term drift characteristics of the MOEMS products. The paper presents a theoretical approach for estimation of lifetime of MOEMS devices in terms of cavity's hermeticity to gases and water. The results are summarized as working maps for MOEMS packaging engineers, in terms of device cavity (internal package volume), equivalent leak rates, and equivalent size of interconnected defects in the bonding zone.