Implantable medical device with hydrogen getter
View Patent ↗Hydrogen getters are provided in active implantable medical device by applying a layer of selected metal with a chosen thickness over an un-oxidized portion of a base metal. The base metal may be titanium, and the selected metal may be palladium or platinum, with a thickness of less than 250 nanometers, where the selected metal acts as a passivation layer relative to oxidation but allows hydrogen capture by the base metal. The getter may be a separate component or may be formed as part of an existing component such as a feedthrough ferrule.
1 . An implantable medical device comprising:
a canister housing operational circuitry for performing functions of the implantable medical device;
a hydrogen getter comprising a titanium layer coated with a layer of selected metal having a chosen thickness, the selected metal and chosen thickness being permeable to hydrogen and substantially impermeable to oxygen, preventing oxidation of the titanium layer in the location of the layer of selected metal while allowing hydrogen to pass therethrough.
2 . The implantable medical device of claim 1 , wherein the selected metal is palladium, and the chosen thickness is in the range of about 2 nanometers to about 250 nanometers.
3 . The implantable medical device of claim 1 , wherein the selected metal is platinum, and the chosen thickness is in the range of about 2 nanometers to about 250 nanometers.
4 . The implantable medical device of claim 1 wherein the canister defines an opening in which a feedthrough assembly resides, and the hydrogen getter is part of a ferrule which surrounds the feedthrough assembly, the ferrule made of titanium and having thereon the layer of selected metal having a chosen thickness is placed.
5 . The implantable medical device of claim 4 , wherein the hydrogen getter is formed by removing an oxidation layer from at least a portion of the ferrule, and depositing the selected metal in the selected thickness thereon.
6 . The implantable medical device of claim 5 wherein the selected metal is placed on the portion of the ferrule by vapor deposition.
7 . The implantable medical device of claim 4 , wherein the hydrogen getter is formed by applying a layer of titanium to a portion of the ferrule, and depositing the selected metal in the selected thickness onto the layer of titanium.
8 . The implantable medical device of claim 1 , wherein the hydrogen getter is attached to a component carried inside the canister.
9 . The implantable medical device of claim 8 , wherein the component carried inside the canister includes a titanium layer, and the hydrogen getter is formed by applying the layer of selected metal onto the titanium layer of the component at a location where the titanium layer is not oxidized.
10 . The implantable medical device of claim 8 , wherein the hydrogen getter is a discrete component.