Biocompatible packaging for implantable miniaturized pressure sensor device used for stent grafts: Concept and choice of materials

This paper presents the biocompatible packaging technology of a flexible, miniaturized and wireless pressure sensor device which is connected to a stent graft to monitor the pressure distribution within an aneurysm. The packaging of implantable electronic devices has to comply with several requirements regarding their reliability and biocompatibility especially for long term implants. Building up a miniaturized flexible pressure sensor device consisting of four capacitive pressure sensors, an application-specific integrated circuit (ASIC) and passive components for the wireless data transmission and power consumption requires polymers as substrate and encapsulation materials. Under the stated conditions, polymeric materials as polyimide, silicones, epoxy resins and parylene C are investigated with respect to their barrier properties (ion and water vapor permeability) and their adhesive strength towards each other.