US 8751015 B2 - Graphene Electrodes On A Planar Cubic Silicon Carbide (3c-sic) Long Term Implantable Neuronal Prosthetic Device - The Lens

Graphene Electrodes On A Planar Cubic Silicon Carbide (3c-sic) Long Term Implantable Neuronal Prosthetic Device

Published: Jun 10, 2014
Earliest Priority: Nov 30 2010
Family: 4
Cited Works: 98
Cited by: 16
Cites: 24
Additional Info: Cited Works Full text Published

Abstract

Graphene, can be used to make an implantable neuronal prosthetic which can be indefinitely implanted in vivo. Graphene electrodes are placed on a 3C—SiC shank and electrical insulation is provided by conformal insulating SiC. These materials are not only chemically resilient, physically durable, and have excellent electrical properties, but have demonstrated a very high degree of biocompatibility. Graphene also has a large specific capacitance in electrolytic solutions as well as a large surface area which reduces the chances for irreversible Faradaic reactions. Graphene can easily be constructed on SiC by the evaporation of Si from the surface of that material allowing for mechanically robust epitaxial graphene layers that can be fashioned into electrodes using standard lithography and etching methods.

Claims

An implantable neuronal prosthetic device for placement in a patient for receiving and sending electrical signals, comprising:
at least one electrode shank adapted for arrangement in said patient having at least one graphene electrode contact disposed on its surface and arranged to electrically couple with said patient, said at least one electrode shank being formed on a single crystal cubic silicon carbide.
An implantable neuronal prosthetic device for receiving and sending electrical signals as in claim 1, further comprising an insulation layer of amorphous, polycrystalline, or single crystal silicon carbide disposed over said electrode shank, said insulation layer of amorphous, polycrystalline, or single crystal silicon carbide being removed from said graphene electrode contact.
An implantable neuronal prosthetic device for receiving and sending electrical signals as in claim 1, wherein the graphene electrode is deposited on one side of the electrode shank.
An implantable neuronal prosthetic device for receiving and sending electrical signals as in claim 1, wherein the graphene electrode is deposited on two sides of the electrode shank.
An implantable neuronal prosthetic device for receiving and sending electrical signals as in claim 1, further comprising signal control electronics attached to said at least one electrode shank and in communication with said at least one grapheme electrode contact.
An implantable neuronal prosthetic device for receiving and sending electrical signals as in claim 1, further comprising a plurality of said at least one electrode shanks being arranged into a matrix.
A method of manufacturing an implantable neuronal prosthetic device for placement in a patient for receiving and sending electrical signals, comprising the steps of:
forming at least one electrode shank adapted for arrangement in said patient out of a single crystal cubic silicon carbide;

forming a layer of graphene sheet on a surface of at least one electrode shank; and

patterning the layer of graphene sheet to at least one graphene electrode contact, said at least one electrode being arranged to electrically couple with said patient.
The method of claim 7, wherein the at least one electrode shank is formed by heteroepitaxially growing the crystal cubic silicon carbide on a cubic lattice crystalline substrate wafer.
The method of claim 8, wherein the silicon carbide is grown on one side of cubic lattice crystalline substrate wafer, and further comprising removing the substrate wafer from the other side of the substrate wafer.
The method of claim 9, wherein removing substrate wafer is achieved by using wet or dry etching techniques.
The method of claim 8, wherein silicon carbide is grown on both sides of cubic lattice crystalline substrate wafer, and further comprising temporarily bonding the graphene electrode side to a supporting wafer, and cleaning interface defects on the other side.
The method of claim 11, wherein cleaning the interface defects is achieved by the reactive ion etching about 6 μm microns of silicon carbide.
The method of claim 7, wherein forming the layer of graphene sheet upon the surface is achieved by high-temperature annealing in Ar ambient to realize thermal decomposition of the 3C—SiC surface.
The method of claim 7, wherein forming the layer of graphene sheet upon the surface is through ultra high vacuum annealing to decompose the 3C—SiC surface.
The method of claim 7, wherein patterning the graphene sheet into electrode contact is through common lithographic techniques and O2 plasma etching.
The method of claim 7, wherein at least one graphene electrode contact is formed upon the surface.
The method of claim 7, further comprising the steps of:
insulating said at least one electrode shank with amorphous, polycrystalline, or single crystal silicon carbide; and

removing said insulating layer of amorphous, polycrystalline, or single crystal silicon carbide from said at least one graphene electrode contacts such that said at least one electrode contacts are exposed.
A method of manufacturing an implantable neuronal prosthetic for placement in a patient for receiving and sending electrical signals as in claim 7, further comprising the step of attaching signal control electronics to said at least one electrode shank, said signal controls electronics being in communication with said at least one electrode contact.
A method of manufacturing an implantable neuronal prosthetic for placement in a patient for receiving and sending electrical signals as in claim 7, further comprising the step of arranging a plurality of said at least one electrode shanks into a matrix.