Barrier properties of polymer encapsulation materials for implantable microsystems

Biocompatible polymers utilized for flexible encapsulations of implantable microsystems provide many advantages compared to widely used rigid titanium or ceramic packages. However, polymers alter their properties due to interactions with their environment. As a result the protective function of these materials especially for long-term implants is not reliable. Therefore, we investigated barrier properties against water vapor of silicone and Parylene C membranes. And we combined these polymers to a multi-layer membrane to enhance the protective function of such an encapsulation system. Applying a bonding agent between two polymer layers increases the strength of the sample as well as the barrier properties significantly.