title: Development, manufacturing and application of double-sided flexible implantable microelectrodes.
abstract: Many neuroprosthetic applications require the use of very small, flexible multi-channel microelectrodes (e.g. polyimide-based film-like electrodes) to fit anatomical constraints. By arranging the electrode contacts on both sides of the polyimide film, selectivity can be further increased without increasing size. In this work, two approaches to create such double-sided electrodes are described and compared: sandwich electrodes prepared by precisely gluing two single-sided structures together, and monolithic electrodes created using a new double-sided photolithography process. Both methods were successfully applied to manufacture double-sided electrodes for stimulation of the vestibular system. In a case study, the electrodes were implanted in the semicircular canals of three guinea pigs and proven to provide electrical stimulation of the vestibular nerve. For both the monolithic electrodes and the sandwich electrodes, long-term stability and functionality was observed over a period of more than 12 months. Comparing the two types of electrodes with respect to the manufacturing process, it can be concluded that monolithic electrodes are the preferred solution for very thin electrodes (<20 μm), while sandwich electrode technology is especially suitable for thicker electrodes (40-50 μm).
authors: Department Medical Engineering and Neuroprosthetics, Fraunhofer Institute for Biomedical Engineering, 66386, Ensheimer Strasse 48, St. Ingbert, Germany, wigand.poppendieck@ibmt.fraunhofer.de.
authors: Wigand
authors: W
authors: Poppendieck
authors: Adam
authors: A
authors: Sossalla
authors: Marc-Oliver
authors: MO
authors: Krob
authors: Christine
authors: C
authors: Welsch
authors: T A Khoa
authors: TA
authors: Nguyen
authors: Wangsong
authors: W
authors: Gong
authors: Jack
authors: J
authors: DiGiovanna
authors: Silvestro
authors: S
authors: Micera
authors: Daniel M
authors: DM
authors: Merfeld
authors: Klaus-Peter
authors: KP
authors: Hoffmann
mesh_terms: D000818:Animals; D004558:Electric Stimulation / Q000295:instrumentation / Q000379:methods; D004567:Electrodes, Implanted; D006168:Guinea Pigs; D006801:Humans; D008567:Membranes, Artificial; D008839:Microelectrodes; D011474:Prosthesis Design; D012117:Resins, Synthetic / Q000737:chemistry; D014725:Vestibular Nerve
chemical_list: D008567:Membranes, Artificial; D012117:Resins, Synthetic; C029945:polyimide resin