Biocompatible bonding method and electronics package suitable for implantation
The invention is directed to a method of bonding a hermetically sealed electronics package to an electrode or a flexible circuit and the resulting electronics package, that is suitable for implantation in living tissue, such as for a retinal or cortical electrode array to enable restoration of sight to certain non-sighted individuals. The hermetically sealed electronics package is directly bonded to the flex circuit or electrode by electroplating a biocompatible material, such as platinum or gold, effectively forming a plated rivet-shaped connection, which bonds the flex circuit to the electronics package. The resulting electronic device is biocompatible and is suitable for long-term implantation in living tissue.
1. A device comprising:
a substrate forming part of a hermetic package, at least a portion of which is electrically conductive;
a flexible assembly; and
at least one rivet, deposited on said electrically conductive portion of said substrate that bonds said substrate and said flexible assembly together.
2. The device according to claim 1 wherein said device is implantable.
3. The device according to claim 1 wherein said at least one deposited rivet is deposited electrochemically.
4. The device according to claim 1 wherein a biocompatible adhesive bonds said substrate and said flexible assembly.
5. The device according to claim 1 wherein said rivet comprises a biocompatible material.
6. The device according to claim 1 wherein said rivet comprises platinum or a platinum alloy.
7. The device according to claim 6 wherein electrochemical deposition is accomplished at a current density of 50 to 2000 mA/cm 2 .
8. The device according to claim 6 wherein electrochemical deposition is accomplished by pulse current control.
9. The device according to claim 1 wherein said flexible assembly comprises polyimide.
10. The device according to claim 1 wherein said substrate comprises a biocompatible ceramic.
11. The device according to claim 10 wherein said biocompatible ceramic comprises alumina.
12. The device according to claim 1 wherein:
at least a part of said substrate forms an electronics control unit; and
said electronics control unit encapsulates electronics.
13. The device according to claim 1 wherein said substrate is rigid.
14. The device according to claim 1 wherein said substrate is an electrically insulated integrated circuit.
15. The device according to claim 1 wherein said flexible assembly is a thin integrated circuit.