Scalable flexible chip-level parylene package for high lead count retinal prostheses

The authors presented an innovative technology for the fabrication of a biocompatible parylene-based high lead count retinal prosthesis in which a prefabricated stand-alone application-specific integrated circuit (ASIC) is placed directly into the fabrication process of the other system components. The package is fabricated in such a way that the ASIC-to-electrode interconnects are patterned using standard photolithography. The density of interconnects is fully scalable to the limits of lithography. This packaging scheme also enables the simultaneous integration and interconnection of discrete components such as chip capacitors with the rest of the system. Electrical test results verify the efficacy of this cost-effective and high-yield packaging scheme, and pave the way for a monolithic implantable parylene-based intraocular system.