Implantable package to facilitate inspection
The present invention is a non-destructive method of inspecting a bond, particularly a braze bond, in a hermetic package. The invention involves a unique hermetic package design adapted for ultrasonic inspection and a method of inspecting the package. This package and non-destructive inspection process are particularly useful in implantable neural stimulators such as visual prostheses.
1. A hermetic package comprising:
a top;
a bottom;
a bond attaching the top to the bottom;
wherein the top, bottom and bond form a rigid, biocompatible, hermetic package suitable for implantation within a human body; and
wherein the bond is parallel to and sufficiently proximate to an outside surface to allow acoustic inspection of the bond.
2. The hermetic package according to claim 1 , wherein the bond is less than 500 μm from the outside surface.
3. The hermetic package according to claim 1 , wherein the bond is selected from the group consisting of a braze bond and a solder bond.
4. The hermetic package according to claim 1 , wherein the top and the bottom are selected from the group consisting of a metal and a ceramic.
5. The hermetic package according to claim 1 , wherein the bottom is optically opaque.
6. The hermetic package according to claim 1 , wherein the top further comprises a lip around the bottom.
7. The hermetic package according to claim 1 , wherein the hermetic package is suitable for implantation within a human body as a neural stimulator.
8. The hermetic package according to claim 1 , wherein the hermetic package is suitable for implantation within a human body as a visual prosthesis.
9. The hermetic package according to claim 1 , wherein the bottom is flat, the top is curved and the bond is to an edge of the top.
10. The hermetic package according to claim 1 , wherein the bottom is a ceramic substrate including electrical feedthroughs.
11. The hermetic package according to claim 9 , further comprising electronic circuits mounted to the substrate and connected to the feedthroughs.
12. The hermetic package according to claim 10 , wherein the electronic circuits include a flip chip.
13. The hermetic package according to claim 10 , wherein the electronic circuits include a wire bonded circuit.
14. The hermetic package according to claim 10 , wherein the electronics circuit includes a flip chip and a wire bonded circuit.