Hermetic terminal for an AIMD having a pin joint in a feedthrough capacitor or circuit board

• US 10,449,375 B2
• Filed: 12/18/2017
• Issued: 10/22/2019
• Est. Priority Date: 12/22/2016
• Status: Active Grant

• Current Assignee: Greatbatch Limited (Greatbatch Incorporated)
• Original Assignee: Greatbatch Limited (Greatbatch Incorporated)
• Inventors: Frustaci, Dominick J., Seitz, Keith W., Marzano, Thomas, Stevenson, Robert A., Frysz, Christine A., Brendel, Richard L., Woods, Jason
• Primary Examiner(s): Hulbert, Amanda K
• Assistant Examiner(s): Edwards, Philip C
• Application Number:
  US15/844,683
• Publication Number:
  US 20180178016A1
• Time in Patent Office: 673 Days
• Field of Search: 607 37
• CPC Class Codes: A61N 1/05 for implantation or insertion into the body, e.g. heart electrode A61N1/06 takes precedence
• CPC Class Codes: A61N 1/08 Arrangements or circuits for monitoring, protecting, controlling or indicating for external stimulators A61N1/3603; for implantable neurostimulators A61N1/36128; for heart stimulators A61N1/37; for defibrillators A61N1/3925
• CPC Class Codes: A61N 1/3754 Feedthroughs
• CPC Class Codes: H01G 2/103 Sealings, e.g. for lead-in wires; Covers
• CPC Class Codes: H01G 2/22 Electrostatic or magnetic shielding
• CPC Class Codes: H01G 4/35 Feed-through capacitors or anti-noise capacitors
• CPC Class Codes: H01G 4/40 Structural combinations of fixed capacitors with other electric elements, the structure mainly consisting of a capacitor, e.g. RC combinations
• CPC Class Codes: H01R 13/7195 with planar filters with openings for contacts
• CPC Class Codes: H01R 2201/12 for medicine and surgery
• CPC Class Codes: H05K 1/0231 Capacitors or dielectric substances
• CPC Class Codes: H05K 2201/10015 Non-printed capacitor
• CPC Class Codes: H05K 2201/10189 Non-printed connector
• CPC Class Codes: H05K 2201/10303 Pin-in-hole mounted pins

Abstract

A hermetically sealed feedthrough subassembly attachable to an active implantable medical device includes a first conductive leadwire extending from a first end to a second end, the first conductive leadwire first end disposed past a device side of an insulator body. A feedthrough filter capacitor is disposed on the device side. A second conductive leadwire is disposed on the device side having a second conductive leadwire first end at least partially disposed within a first passageway of the feedthrough filter capacitor and having a second conductive leadwire second end disposed past the feedthrough filter capacitor configured to be connectable to AIMD internal electronics. The second conductive leadwire first end is at, near or adjacent to the first conductive leadwire first end. A first electrically conductive material forms a three-way electrical connection electrically connecting the second conductive leadwire first end, the first conductive leadwire first end and a capacitor internal metallization.

Claims

1. A hermetically sealed feedthrough subassembly attachable to an active implantable medical device (AIMD), the feedthrough subassembly comprising:

a) an insulator substrate assembly, comprising;

i) an insulator body defined as having a body fluid side opposite a device side, the body fluid side and device side separated and connected by at least one outer perimeter surface;

ii) at least one via hole disposed through the insulator body and extending from the body fluid side to the device side;

iii) an internal metallization formed at least partially on an inside of the at least one via hole;

iv) a first conductive leadwire extending from a first end to a second end, wherein the first conductive leadwire is at least partially disposed within the at least one via hole and wherein the first conductive leadwire first end is disposed outwardly beyond the device side of the insulator body;

v) a first braze residing at least partially between the first conductive leadwire and the internal metallization, the first braze forming a first hermetic seal separating the body fluid side from the device side; and

vi) an external metallization disposed at least partially on the at least one outer perimeter surface of the insulator body; and

b) a ferrule, comprising;

i) a conductive ferrule body defined as having a ferrule first side opposite a ferrule second side and defining a ferrule opening between and through the ferrule first and second sides, wherein the insulator body is at least partially disposed within the ferrule opening; and

ii) a second braze residing at least partially between the external metallization of the insulator body and the conductive ferrule body, the second braze forming a second hermetic seal hermetically sealing the ferrule opening;

c) a feedthrough filter capacitor disposed on the device side, the feedthrough filter capacitor comprising;

i) at least one active electrode plate disposed parallel and spaced from at least one ground electrode plate, wherein the active and ground electrode plates are disposed within a capacitor dielectric substrate;

ii) a first passageway disposed through the capacitor dielectric substrate and disposed perpendicular to the active and ground electrode plates; and

iii) a capacitor internal metallization disposed within the first passageway and being electrically connected to the at least one active electrode plate and in non-conductive relation with the at least one ground electrode plate;

iv) wherein the first conductive leadwire first end is disposed within the first passageway;

d) a second conductive leadwire disposed on the device side and having a second conductive leadwire first end at least partially disposed within the first passageway of the feedthrough filter capacitor and having a second conductive leadwire second end disposed outwardly beyond the feedthrough filter capacitor, the second conductive leadwire second end being configured to be connectable to electronics internal to the AIMD, wherein the second conductive leadwire first end is at, near or adjacent to the first conductive leadwire first end; and

e) a first electrically conductive material forming at least a three-way electrical connection electrically connecting the second conductive leadwire first end, the first conductive leadwire first end and the capacitor internal metallization together.

2. The feedthrough subassembly of claim 1, wherein the first electrically conductive material is selected from the group consisting of a solder, a solder BGA, a solder paste, a conductive epoxy, and a conductive polyimide.

3. The feedthrough subassembly of claim 1, wherein the first conductive leadwire is not of the same material as the second conductive leadwire.

4. The feedthrough subassembly of claim 1, wherein the first conductive leadwire comprises platinum, palladium, niobium, tantalum or alloys thereof.

5. The feedthrough subassembly of claim 1, wherein the first braze and second braze each comprise a gold braze.

6. The feedthrough subassembly of claim 5, wherein the first electrically conductive material directly contacts and is electrically connected to the first gold braze.

7. The feedthrough subassembly of claim 1, wherein the first braze is disposed at or near the device side and does not extend to, at or near the body fluid side.

8. The feedthrough subassembly of claim 1, wherein the first braze is disposed at or near the device side and does extend to, at or near the body fluid side.

9. The feedthrough subassembly of claim 1, wherein the first and second hermetic seals have a leak rate no greater than 1×

10−

7 std cc He/sec.

10. The feedthrough subassembly of claim 1, wherein the external metallization disposed at least partially on the at least one outer perimeter surface of the insulator body comprises an adhesion metallization and a wetting metallization, wherein the adhesion metallization is disposed at least partially on the at least one outer perimeter surface of the insulator body and wherein the wetting metallization is disposed on the adhesion metallization.

11. The feedthrough subassembly of claim 1, wherein the adhesion metallization or the wetting metallization comprise at least one of niobium or titanium.

12. The feedthrough subassembly of claim 1, wherein an insulative washer is disposed between the insulator substrate assembly and the feedthrough filter capacitor.

13. The feedthrough subassembly of claim 1, wherein the ferrule is configured to be joined to an opening in an AIMD housing by a laser weld or braze.

14. The feedthrough subassembly of claim 1, wherein the ferrule is formed from and as a continuous part of an AIMD housing.

15. The feedthrough subassembly of claim 1, including a capacitor external metallization disposed on an outside perimeter surface of the capacitor dielectric substrate and being electrically connected to the at least one ground electrode plate and in non-conductive relation with the at least one active electrode plate.

16. The feedthrough subassembly of claim 15, including a second electrically conductive material electrically connecting the capacitor external metallization to the ferrule and/or to the second braze.

17. The feedthrough subassembly of claim 1, including at least one internal ground plate disposed within the insulator body and being electrically connected to the at least one ground electrode plate of the feedthrough filter capacitor and being electrically connected to the ferrule.

18. The feedthrough subassembly of claim 1, including a third conductive ground leadwire at least partially disposed within the insulator body and having a third conductive ground leadwire first end disposed outwardly beyond the device side of the insulator body, wherein the third conductive ground leadwire is electrically connected to the at least one ground electrode plate of the feedthrough filter capacitor.

19. The feedthrough subassembly of claim 18, including a braze channel electrically connected between and to the third conductive leadwire and the ferrule.

20. The feedthrough subassembly of claim 19, wherein the feedthrough filter capacitor does not have an external metallization disposed on an outside perimeter surface of the capacitor dielectric substrate.

21. The feedthrough subassembly of claim 19, including a conductive clip electrically connected between and to the third conductive leadwire and the ferrule.

22. The feedthrough subassembly of claim 19, wherein the conductive ferrule body includes a conductive peninsula extending at least partially into the ferrule opening, and wherein the third conductive leadwire is electrically connected to the conductive peninsula with a third braze.

23. A hermetically sealed feedthrough subassembly attachable to an active implantable medical device (AIMD), the feedthrough subassembly comprising:

a) an insulator body defined as having a body fluid side opposite a device side, the body fluid side and device side separated and connected by at least one outer perimeter surface, wherein at least one via hole disposed through the insulator body extends from the body fluid side to the device side;

b) an internal metallization formed at least partially on an inside of the at least one via hole;

c) a first conductive leadwire extending from a first end to a second end, wherein the first conductive leadwire is at least partially disposed within the at least one via hole and wherein the first conductive leadwire first end is disposed outwardly beyond the device side of the insulator body;

d) a first gold braze residing at least partially between the first conductive leadwire and the internal metallization, the first gold braze forming a first hermetic seal separating the body fluid side from the device side;

e) an external metallization disposed at least partially on the at least one outer perimeter surface of the insulator body; and

f) a conductive ferrule body defined as having a ferrule first side opposite a ferrule second side and defining a ferrule opening between and through the ferrule first and second sides, wherein the conductive ferrule body is configured to be joined to an opening in an AIMD housing by a laser weld or braze;

g) a second gold braze residing at least partially between the external metallization of the insulator body and the conductive ferrule body, the second gold braze forming a second hermetic seal hermetically sealing the ferrule opening to the conductive ferrule body;

h) a feedthrough filter capacitor disposed on the device side, the feedthrough filter capacitor comprising;

i) at least one active electrode plate disposed parallel and spaced from at least one ground electrode plate, wherein the active and ground electrode plates are disposed within a capacitor dielectric substrate;

ii) a first passageway disposed through the capacitor dielectric substrate and disposed perpendicular to the first and second plates; and

iii) a capacitor internal metallization disposed within the first passageway and being electrically connected to the at least one active electrode plate and in non-conductive relation with the at least one ground electrode plate;

iv) wherein the first conductive leadwire first end is disposed within the first passageway;

i) a second conductive leadwire disposed on the device side and having a second conductive leadwire first end at least partially disposed within the first passageway of the feedthrough filter capacitor and having a second conductive leadwire second end disposed outwardly beyond the feedthrough filter capacitor, the second conductive leadwire second end being configured to be connectable to electronics internal to the AIMD, wherein the second conductive leadwire first end is at, near or adjacent to the first conductive leadwire first end, and wherein the first conductive leadwire is not of the same material as the second conductive leadwire; and

j) a first electrically conductive material forming at least a three-way electrical connection electrically connecting the second conductive leadwire first end, the first conductive leadwire first end and the capacitor internal metallization together.