Long-term evaluation of a non-hermetic micropackage technology for MEMS-based, implantable pressure sensors

This paper reports long-term evaluation of a micropackage technology for an implantable MEMS pressure sensor. The all-polymer micropackage survived > 160 days when subjected to accelerated lifetime testing at 85°C in a 1% wt. saline solution. The package exhibited minimum impact on sensitivity and linearity, which deviated by less than 5% and 0.3%, respectively. A 6-month in vivo evaluation of 16 MEMS-based pressure sensors showed that the micropackage exhibits good biocompatibility and provides excellent protection. To the best of our knowledge, these results establish new lifetime records for devices packaged using an all-polymer micropackaging approach.