PROCESS FOR FORMING AN ISOLATED ELECTRICALLY CONDUCTIVE CONTACT THROUGH A METAL PACKAGE

• US 20080289178A1
• Filed: 05/25/2007
• Published: 11/27/2008
• Est. Priority Date: 05/25/2007
• Status: Active Grant

• Current Assignee: Electro Scientific Industries Incorporated (MKS Instruments Incorporated)
• Original Assignee: Electro Scientific Industries Incorporated (MKS Instruments Incorporated)
• Inventors: Nashner, Michael, Howerton, Jeff
• Granted Patent: US 7,886,437 B2
• Time in Patent Office: Days
• US Class Current: 29/852
• CPC Class Codes: H05K 1/053 the metal substrate being covered by an inorganic insulating layer
• CPC Class Codes: H05K 2201/0179 Thin film deposited insulating layer, e.g. inorganic layer for printed capacitor
• CPC Class Codes: H05K 2201/09581 Applying an insulating coating on the walls of holes
• CPC Class Codes: H05K 2201/09827 Tapered, e.g. tapered hole, via or groove bevelled, chamferred or tapered edge H05K2201/09154
• CPC Class Codes: H05K 2203/0315 Oxidising metal
• CPC Class Codes: H05K 2203/0323 Working metal substrate or core, e.g. by etching, deforming
• CPC Class Codes: H05K 2203/107 Using laser light shaping a substrate by laser ablation H05K3/0026
• CPC Class Codes: H05K 3/4061 for via connections in inorganic insulating substrates
• CPC Class Codes: H05K 3/445 having insulated holes or insulated via connections through the metal core
• CPC Class Codes: H05K 5/0247 Electrical details of casings, e.g. terminals, passages for cables or wiring
• CPC Class Codes: Y10T 29/49155 Manufacturing circuit on or in base
• CPC Class Codes: Y10T 29/49165 by forming conductive walled aperture in base

Abstract

A method of forming an isolated electrically conductive contact through a metal substrate by creating at least one via through the substrate. The at least one sidewall of the via is cleaned and coated with a non-conductive layer. In one example, the non-conductive layer is formed by anodizing the sidewall(s) of the via. In another example, the non-conductive layer may be formed by thin film deposition of a dielectric on the sidewall(s). An electrically conductive filler is then placed into the via. In the examples disclosed, the filler may be a conductive ink or a conductive epoxy.

Claims

1. A method of creating an electrically isolated contact comprising:

forming a via in a metallic substrate wherein the via includes at least one sidewall;

forming a dielectric sleeve on the at least one sidewall of the via; and

filling the via with an electrically conductive material.

2. The method as in claim 1 wherein the dielectric sleeve is formed through anodization.

3. The method as in claim 2 wherein the substrate is comprised of aluminum and the aluminum is anodized after the via is formed.

4. The method as in claim 3 wherein the at least one sidewall of the via is cleaned with an etching process prior to anodizing.

5. The method as in claim 4 wherein the via is cleaned using a sodium hydroxide alkaline etch.

6. The method as in claim 1 wherein the dielectric sleeve is formed through chemical vapor deposition.

7. The method as in claim 1 wherein the substrate includes a pocket formed therein, the pocket including at least one sidewall and a base and the vias being formed in the base of the pocket.

8. The method as in claim 1 wherein the electrically transmissive material is a conductive ink.

9. The method as in claim 1 wherein the electrically transmissive material is a silver nano particle liquid conductive epoxy.

10. The method as in claim 1 wherein the via is conically shaped.

11. The method as in claim 10 wherein the via includes a first end having a first diameter between 90 to 200 micrometers and a second end having a second diameter between 20 to 50 micrometers.

12. A housing having an electrically isolated contact formed using the method of claim 1.

13. A housing having an isolated electrical contact wherein the isolated electrical contact comprises:

a via having an electrically insulating sleeve formed on a via sidewall and a conductive filler captured by the insulating sleeve of the via sidewall.

14. The housing as in claim 13 wherein the housing is made from aluminum.

15. The housing as in claim 14 wherein the insulating sleeve is a layer of anodized aluminum.

16. The housing as in claim 15 comprising a portion of an antenna using the plurality of isolated electrical contacts.

17. A housing made from a metal and having an isolated electrical contact wherein the isolated electrical contact is formed by a method comprising:

forming a via in the housing, the via including at least one sidewall;

cleaning the housing and the at least one sidewall;

anodizing the housing and the at least one sidewall; and

filling the via with an electrically conductive filler.

18. The housing as in claim 17 wherein the via has a diameter between 20 and 200 microns.

19. The housing as in claim 18 wherein the via is drilled using a laser.

20. The housing as in claim 19 wherein the isolated electrical contact operates as an on/off switch.