Feedthrough assemblies and methods of forming same

Patent metadata

Field	Value
Publication number	US-2016190052-A1
Application number	US-201514966101-A
Country	US
Kind code	A1
Filing date	Dec 11, 2015
Priority date	Dec 24, 2014
Publication date	Jun 30, 2016
Grant date	—

Abstract

Various embodiments of a feedthrough assembly and methods of forming such assemblies are disclosed. In one or more embodiments, the feedthrough assembly can include a non-conductive substrate and a feedthrough. The feedthrough can include a via from an outer surface to an inner surface of the non-conductive substrate, a conductive material disposed in the via, and an external contact disposed over the via on the outer surface of the non-conductive substrate. The external contact can be electrically coupled to the conductive material disposed in the via. And the external contact can be hermetically sealed to the outer surface of the non-conductive substrate by a bond surrounding the via. In one or more embodiments, the bond can be a laser bond.

First claim

What is claimed is:

1 . A feedthrough assembly comprising a non-conductive substrate and a feedthrough, the feedthrough comprising:
a via from an outer surface to an inner surface of the non-conductive substrate; a conductive material disposed in the via; and an external contact disposed over the via on the outer surface of the non-conductive substrate, wherein the external contact is electrically coupled to the conductive material disposed in the via, and wherein the external contact is hermetically sealed to the outer surface of the non-conductive substrate by a laser bond surrounding the via.

2 . The assembly of claim 1 , wherein the feedthrough further comprises an internal contact disposed over the via on the inner surface of the non-conductive substrate, wherein the internal contact is electrically coupled to the conductive material disposed in the via, and wherein the internal contact is attached to the inner surface of the non-conductive substrate by a laser bond that surrounds the via.

3 . The assembly of claim 1 , wherein the laser bond that hermetically seals the external contact to the outer surface of the non-conductive substrate comprises a bond line.

4 . The assembly of claim 3 , wherein the bond line that hermetically seals the external contact to the outer surface of the non-conductive substrate comprises an interfacial layer between the external contact and the non-conductive substrate.

5 . The assembly of claim 4 , wherein the interfacial layer has a thickness in a direction normal to the outer surface of the non-conductive substrate of no greater than 10 μm.

6 . The assembly of claim 1 , wherein the non-conductive substrate is substantially transmissive to light having a wavelength of between 1 nm and 30 μm.

7 . The assembly of claim 1 , wherein the non-conductive substrate comprises at least one of glass, quartz, silica, sapphire, silicon carbide, diamond, and gallium nitride, and alloys or combinations thereof.

8 . The assembly of claim 1 , wherein the external contact comprises at least one of copper, silver, titanium, niobium, zirconium, tantalum, stainless steel, platinum, iridium, and alloys or combinations thereof.

9 . The assembly of claim 1 , wherein the external contact comprises a thickness in a direction normal to the outer surface of the non-conductive substrate of at least 10 micrometers.

10 . The assembly of claim 1 , further comprising a weld ring hermetically sealed to the outer surface of the non-conductive substrate by a laser bond adjacent a perimeter of the substrate, wherein the weld ring surrounds the external contact.

11 . The assembly of claim 1 , further comprising an electronic device disposed on the inner surface of the non-conductive substrate, wherein the electronic device is electrically coupled to the conductive material in the via of the feedthrough, and wherein the electronic device is attached to the non-conductive substrate by a bond.

12 . The assembly of claim 11 , wherein the electronic device comprises an integrated circuit.

13 . The assembly of claim 1 , wherein the via comprises an opening at the outer surface of the non-conductive substrate that has a diameter of no greater than 500 micrometers.

14 . The assembly of claim 1 , wherein the laser bond that hermetically seals the external contact to the outer surface of the non-conductive substrate comprises a bond line that forms a closed shape in a plane parallel to the outer surface of the non-conductive substrate.

15 . The assembly of claim 1 , further comprising a conductor disposed on the outer surface of the non-conductive substrate and electrically coupled to the external contact.

16 . The assembly of claim 1 , wherein the non-conductive substrate is substantially transmissive to a transmitted light having a pre-determined magnitude such that the energy transmitted through the substantially transparent substrate material is at least one of: sufficient to activate the bonding process at the interface via absorption by the opaque material, and absorbable by the transparent material without melting, distorting, or otherwise modifying the bulk properties of the transparent material away from the bonding region.

17 . The assembly of claim 1 , wherein the feedthrough further comprises a filtering capacitor electrically coupled to the via on the inner surface of the non-conductive substrate, wherein the filtering capacitor comprises a dielectric member interposed between two conductive layers.

18 . A method of forming a feedthrough assembly, comprising:
forming a via through a non-conductive substrate, the non-conductive substrate comprising an outer surface and an inner surface; forming a conductor on the outer surface of the non-conductive substrate; forming an external contact over the via and a portion of the conductor, wherein the external contact is electrically coupled to the conductor; attaching the external contact to the outer surface of the non-conductive substrate by forming a laser bond that surrounds the via and hermetically seals the external contact to the outer surface of the non-conductive substrate; and forming a conductive material in the via that is electrically coupled to the external contact.

19 . The method of claim 18 , wherein forming the external contact comprises:
forming a conductive layer on the outer surface of the non-conductive substrate over the via and the conductor; and removing a portion of the conductive layer to form the external contact over the via and the portion of the conductor.

20 . The method of claim 18 , wherein the laser bond that surrounds the via and hermetically seals the external contact to the outer surface of the non-conductive substrate comprises a bond line, wherein attaching the external contact to the outer surface of the non-conductive substrate comprises laser bonding the external contact to the outer surface of the non-conductive substrate along the bond line that surrounds the via and hermetically seals the external contact to the outer surface of the non-conductive substrate.

21 . The method of claim 20 , wherein laser bonding the external contact comprises:
directing laser light through the inner surface of the non-conductive substrate into the non-conductive substrate; and directing the laser light at the interface of the external contact and the outer surface of the non-conductive substrate.

22 . The method of claim 18 , further comprising forming an internal contact on the inner surface of the non-conductive substrate that is electrically coupled to the conductive material formed in the via.

23 . The method of claim 18 , wherein the conductor comprises a first conductive material and the contact comprises a second conductive material different from the first conductive material.

24 . The method of claim 17 , wherein forming the conductor comprises:
forming a conductive material on the outer surface of the non-conductive substrate; and removing a portion of the conductive material to form the conductor.

25 . The method of claim 18 , further comprising forming the conductor and forming the conductive material in the via simultaneously.

26 . A method of forming a feedthrough assembly, comprising:
forming a conductive layer on an outer surface of a non-conductive substrate; attaching the conductive layer to the outer surface of the non-conductive substrate by formi

Assignees

• Medtronic Inc

Inventors

• Ruben David A
• Sandlin Michael S

Classifications

• H10W70/095

  of vias therein · CPC title

• H10W70/093

  Connecting or disconnecting other interconnections thereto or therefrom, e.g. connecting bond wires or bumps · CPC title

• H10W70/69

  Insulating materials thereof · CPC title

• H10W70/66

  Conductive materials thereof · CPC title

• H10W70/65

  Shapes or dispositions of interconnections · CPC title