Microfabrication of multichannel flexible neural microelectrodes

Multichannel flexible neural microelectrodes were designed and fabricated,and their fabrication processes were also studied.A microfabrication technology was introduced to manufacture flexible microelectrodes based on a new flexible substrate material,parylene C,due to its excellent electrical insulating,mechanical and biocompatible properties,and a 36-channel flexible neural microelectrode was fabricated with the arrangement in a 6×6 square grid pattern.The size of microelectrode was Φ150 μm(circular) and 150 μm×150 μm(squre),respectively,and the line width of metal trace was 30 μm.It was found that the microelectrode shows a smooth surface and a distinct outline.A electrtical test indicates that the impedance of microelectrode is only 7 kΩ or so,and it reduceds as frequency increasing,which is an excellent high-pass behavior.Moreover,the microelectrode and a flexible substrate can be integrated by the microfabrication technology.The microelectrode is suitable for the application in retinal prostheses,for it has a good quality and excellent electrical properties.