Hermetically sealed feedthrough with co-fired filled via and conductive insert for an active implantable medical device

Patent metadata

Field	Value
Publication number	US-9889306-B2
Application number	US-201514797123-A
Country	US
Kind code	B2
Filing date	Jul 11, 2015
Priority date	Jan 16, 2012
Publication date	Feb 13, 2018
Grant date	Feb 13, 2018

Abstract

A hermetically sealed feedthrough for attachment to an active implantable medical device includes a dielectric substrate configured to be hermetically sealed to a ferrule or an AIMD housing. A via hole is disposed through the dielectric substrate from a body fluid side to a device side. A conductive fill is disposed within the via hole forming a filled via electrically conductive between the body fluid side and the device side. A conductive insert is at least partially disposed within the conductive fill. Then, the conductive fill and the conductive insert are co-fired with the dielectric substrate to form a hermetically sealed and electrically conductive pathway through the dielectric substrate between the body fluid side and the device side.

First claim

What is claimed is:

1. A hermetically sealed feedthrough for attachment to an active implantable medical device (AIMD), the feedthrough comprising:
a) a dielectric substrate hermetically sealed to a ferrule by a gold braze;
b) a via hole disposed through the dielectric substrate from a first side to a second side;
c) a conductive sintered paste fill disposed within the via hole forming a filled via electrically conductive between the first side and the second side; and
d) a conductive solid metallic insert at least partially disposed within the conductive sintered paste fill;
e) wherein the conductive sintered paste fill and the conductive solid metallic insert are co-fired with the dielectric substrate forming a hermetically sealed and electrically conductive pathway through the dielectric substrate between the first side and the second side.

2. The feedthrough of claim 1 , wherein the conductive fill comprises a metallic fill.

3. The feedthrough of claim 1 , wherein an inherent shrink rate during a co-firing treatment of the insulator in a green state is greater than that of an inherent shrink rate during the co-firing treatment of the metallic fill in a green state.

4. The feedthrough of claim 1 , wherein first and second ends of the insert are substantially flush with the respective first side and second side of the dielectric substrate.

5. The feedthrough of claim 1 , wherein at least one of an insert first end and an second insert end extends outwardly beyond a respective one of the first side and second side of the dielectric substrate.

6. The feedthrough of claim 5 , wherein the insert comprises an enlarged end cap at least one of its insert first and second ends.

7. A hermetically sealed feedthrough for attachment to an active implantable medical device (AIMD), the feedthrough comprising:
a) a conductive ferrule comprising a ferrule sidewall having an inner ferrule surface defining a ferrule opening, wherein the ferrule sidewall extends from a ferrule first end surface to a ferrule second end surface, and wherein the ferrule is configured to be attachable to an opening in a housing of an active implantable medical device;
b) an insulator residing at least partially within the inner ferrule surface, wherein the insulator comprises an outer insulator surface extending from an insulator first end surface disposed adjacent to the ferrule first end surface to an opposed insulator second end surface disposed adjacent to the ferrule second end surface;
c) a first metallization contacting at least a portion of the outer surface of the insulator;
d) an electrically conductive material hermetically sealing the ferrule sidewall to the first metallization contacting the outer surface of the insulator;
e) at least one via hole extending through the insulator from the insulator first end surface to the insulator second end surface;
f) an electrically conductive insert residing in the via hole and comprising an insert sidewall extending from an insert first end to an insert second end, wherein the insert first end is disposed at or adjacent to the insulator first end surface and the insert second end is disposed at or adjacent to the insulator second end surface; and
g) a conductive fill residing in the at least one via hole in contact with the insert sidewall, the conductive fill extending from a conductive fill first end disposed at or adjacent to the insulator first end surface to a conductive fill second end disposed at or adjacent to the insulator second end surface,
h) wherein the conductive fill is in a hermetically sealed relationship with both the insulator at the at least one via hole and the insert sidewall so that the conductive insert provides an electrically conductive pathway extending through the insulator to or adjacent to the insulator first end surface and to or adjacent to the insulator second end surface.

8. The feedthrough of claim 7 , wherein the conductive fill comprises a metallic fill.

9. The feedthrough of claim 8 , wherein the conductive insert comprises a metallic insert, and where the metallic insert and the metallic fill are of the same metallic material.

10. The feedthrough of claim 8 , wherein an inherent shrink rate during a co-firing treatment of the insulator in a green state is greater than that of an inherent shrink rate during the co-firing treatment of the metallic fill in a green state.

11. The feedthrough of claim 7 , wherein the conductive fill comprises a platinum fill.

12. The feedthrough of claim 11 , wherein the conductive insert comprises a platinum insert.

13. The feedthrough of claim 12 , wherein the insulator comprises an alumina ceramic substrate comprised of at least 96 percent alumina.

14. The feedthrough of claim 7 , wherein the conductive fill is a platinum fill that forms a first tortuous and mutually conformal knitline with the insulator at the at least one via hole.

15. The feedthrough of claim 7 , wherein the conductive fill is a platinum fill that forms a second tortuous and mutually conformal knitline with the insert sidewall, the insert being a platinum insert.

16. The feedthrough of claim 7 , wherein the conductive fill does not contact:
i) the insert first end disposed at or adjacent to the insulator first end surface, and
ii) the insert second end disposed at or adjacent to the insulator second end surface.

17. The feedthrough of claim 7 , wherein the insert first and second ends are substantially flush with the respective insulator first and second end surfaces.

18. The feedthrough of claim 7 , wherein at least one of the insert first and second ends extends outwardly beyond a respective one of the insulator first and second end surfaces.

19. The feedthrough of claim 18 , wherein the insert comprises an enlarged end cap at at least one of its insert first and second ends.

20. The feedthrough of claim 7 , wherein the conductive insert comprises a first insert portion separate and distinct from a second insert portion, and wherein the first and second insert portions are adjacent to or abut one another at an intermediate location along a length of the at least one via hole in which the insert resides.

21. The feedthrough of claim 7 , wherein the conductive insert comprises a crimp post portion extending outwardly beyond at least one of the insulator first and second end surfaces.

22. The feedthrough of claim 21 , wherein the crimp post portion comprises a receptacle configured to receive a conductive wire, and wherein the crimp post portion comprises a cross-sectional shape selected from the group consisting of a circle, an oval, a rectangle, and a square.

23. The feedthrough of claim 22 , wherein the receptacle of the crimp post portion of the conductive insert is disposed perpendicular to a longitudinal length of the crimp post portion.

24. The feedthrough of claim 22 , wherein the receptacle of the crimp post portion of the conductive insert is aligned along a longitudinal length of the crimp post portion.

25. The feedthrough of claim 22 , wherein the crimp post portion of the conductive insert comprises at least one slot that is at least partially disposed along a longitudinal length of the crimp post portion.

26. The feedthrough of claim 7 , wherein the conductive insert has a length extending from the insert first end to the insert second end and wherein at least one slot extends along the length of the conductive insert fro

Assignees

• Greatbatch Ltd

Inventors

• Stevenson Robert A
• Tang Xiaohong
• Thiebolt William C
• Frysz Christine A
• Seitz Keith W
• Brendel Richard L
• Marzano Thomas
• Woods Jason
• Frustaci Dominick J
• Winn Steven W

Classifications

• A61N1/37512

  Pacemakers · CPC title

• C22C29/12

  based on oxides · CPC title

• H01G4/35

  Feed-through capacitors or anti-noise capacitors · CPC title

• H01R43/00

  Apparatus or processes specially adapted for manufacturing, assembling, maintaining, or repairing of line connectors or current collectors or for joining electric conductors (of trolley lines B60M1/28) · CPC title

• A61N1/3754 Primary

  Feedthroughs · CPC title