System of fabricating a flexible electrode array
View Patent ↗An image is captured or otherwise converted into a signal in an artificial vision system. The signal is transmitted to the retina utilizing an implant. The implant consists of a polymer substrate made of a compliant material such as poly(dimethylsiloxane) or PDMS. The polymer substrate is conformable to the shape of the retina. Electrodes and conductive leads are embedded in the polymer substrate. The conductive leads and the electrodes transmit the signal representing the image to the cells in the retina. The signal representing the image stimulates cells in the retina.
1. A system of fabricating a flexible electrode array, comprising the steps of:
spin-coating a poly(dimethylsiloxane) layer (PDMS) onto a handle wafer that has been pre-coated with a conductive seed layer;
patterning said poly(dimethylsiloxane) layer to expose said conductive seed layer to form electrodes;
plating a material for said electrodes until said electrodes are higher than a thickness of said poly(dimethylsiloxane) layer and until said electrodes form mushroom caps which later will prevent said electrodes from popping out of said poly(dimethylsiloxane) layer when said poly(dimethylsiloxane) layer is removed from said handle wafer; and
patterning conducing lines on said poly(dimethylsiloxane) layer.
2. The system of fabricating a flexible electrode array of claim 1 , wherein said step of patterning conducing lines on said PDMS is conducted using thin film deposition.
3. The system of fabricating a flexible electrode array of claim 1 , wherein said step of patterning conducing lines on said PDMS is conducted using photolithography.
4. The system of fabricating a flexible electrode array of claim 1 , wherein said step of patterning conducing lines on said poly(dimethylsiloxane) layer is conducted using shadow masking.
5. The system of fabricating a flexible electrode array of claim 1 , further comprising a step of directly embedding an electrical connector into said poly(dimethylsiloxane) layer to interface with electronics.
6. The system of fabricating a flexible electrode array of claim 1 , further comprising a step of casting a PDMS capping layer to said PDMS.
7. The system of fabricating a flexible electrode array of claim 1 , further comprising a step of bonding a poly(dimethylsiloxane) capping layer to said poly(dimethylsiloxane) layer.
8. The system of fabricating a flexible electrode array of claim 1 , wherein said conductive seed layer is made of biocompatible.
9. The system of fabricating a flexible electrode array of claim 1 , wherein said conductive seed layer is made of gold.
10. The system of fabricating a flexible electrode array of claim 1 , wherein said conductive seed layer is made of platinum.
11. The system of fabricating a flexible electrode array of claim 1 , wherein said conductive seed layer is made of a conductive polymer material.
12. The system of fabricating a flexible electrode array of claim 1 , wherein in said step of plating a material for said electrodes until said electrodes are higher than the thickness of said poly(dimethylsiloxane) layer and until said electrodes form mushroom caps which later will prevent said electrodes from popping out of said poly(dimethylsiloxane) layer when said poly(dimethylsiloxane) layer is removed from said handle wafer and said electrodes are gold electrodes electroplated onto said conductive seed layer.
13. The system of fabricating a flexible electrode array of claim 1 , wherein the material is made of platinum electroplated onto said conductive seed layer.
14. The system of fabricating a flexible electrode array of claim 1 , further comprising a step of directly embedding an integrated circuit into said poly(dimethylsiloxane) layer such that said integrated circuit interfaces with the electrode array.