Long-term in-vivo Investigation of Parylene-C as Encapsulation Material for Neural Interfaces

AbstractIn this paper, we present in-vitro soak testing results used to measure the long term encapsulation and insulation properties of parylene-C based on interdigitated electrodes (IDEs) (Fig. 1). The parylene-C layer has been deposited by chemical vapor deposition using the Gorman process [1]. Our primary investigations showed that parylene-C is a great encapsulation material based on its extremely low leakage current (20 pA for quartz substrate) and high insulation impedance (2 Masterisk at 1kHz for quartz substrate) after 180-day of soaking test. Substrate materials with high resistivity were recommended in order to actually measure the insulation performance of encapsulation materials rather than that of the substrates