MEMSmicroelektromechanische

MEMS microelectrodes are microfabricated electrode devices that employ microelectromechanical systems (MEMS) processing to interface with biological tissue, primarily for recording neural activity or delivering electrical stimulation. By leveraging batch fabrication, they enable high-density electrode arrays with small footprints suitable for chronic implantation or research probes.

They are typically built on silicon or flexible polymer substrates using MEMS techniques such as photolithography, etching, and thin-film deposition. Electrode contacts are commonly made from platinum, platinum-iridium, or iridium oxide; alternative materials include gold, carbon-based materials (carbon nanotubes, graphene), and conductive polymers like PEDOT. Flexible substrates such as polyimide or parylene offer reduced mechanical mismatch with tissue, and many devices incorporate on-chip electronics (CMOS) for multiplexed recording and stimulation.

Applications include neuroscience research and neural interfaces, brain–machine interfaces, epilepsy monitoring, and neuroprosthetics. Penetrating arrays such as Utah and Michigan probes reach neural tissue to record single-unit activity, while planar or flexible mesh designs provide less invasive interfaces and chronic recordings. High-density systems, such as Neuropixels probes, couple MEMS microfabrication with integrated electronics to enable thousands of recording sites.

Challenges include the brain’s tissue response (gliosis), micromotion-induced damage, impedance drift, and long-term stability. Mechanical mismatch between rigid probes and soft brain tissue, sterilization, and reliable packaging also pose hurdles. Ongoing research seeks improved biocompatibility, site impedance control, wireless data and power, and scalable clinical translation of MEMS microelectrodes.