Process for forming an isolated electrically conductive contact through a metal package

• US 7,886,437 B2
• Filed: 05/25/2007
• Issued: 02/15/2011
• Est. Priority Date: 05/25/2007
• Status: Expired due to Fees

• Current Assignee: Electro Scientific Industries Incorporated (MKS Instruments Incorporated)
• Original Assignee: Electro Scientific Industries Incorporated (MKS Instruments Incorporated)
• Inventors: Nashner, Michael, Howerton, Jeff
• Primary Examiner(s): Banks; Derris H
• Assistant Examiner(s): PARVEZ, AZM A
• Application Number:
  US11/753,996
• Publication Number:
  US 20080289178A1
• Time in Patent Office: 1,362 Days
• Field of Search: 298/52, 257/E23.011, 257/E23.067, 257/E23.145, 257/E29.119, 257/E21.577, 257/E21.578, 257/E21.774, 438/8, 438/689, 438/696, 438/694
• 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
• 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
• 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 a first opening in a top surface of the metallic substrate, a second opening in an opposing bottom surface of the metallic substrate and at least one sidewall extending between the first opening and the second opening;

forming a dielectric sleeve on the at least one sidewall of the via, the dielectric sleeve formed through anodization; and

filling the via with an electrically conductive material.

2. The method as in claim 1 wherein the substrate is comprised of aluminum and the aluminum is anodized after the via is formed.

3. The method as in claim 2 wherein the at least one sidewall of the via is cleaned with an etching process prior to anodizing.

4. The method as in claim 3 wherein the via is cleaned using a sodium hydroxide alkaline etch.

5. 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 via being formed in the base of the pocket.

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

12. The method of claim 1 wherein the electrically conductive material is a conductive ink.

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

a via having a first opening in a top surface of a portion of the housing, a second opening in an opposing bottom surface of the portion and a via sidewall extending between the first opening and the second opening;

an electrically insulating sleeve formed on the via sidewall; and

a conductive filler captured by the insulating sleeve of the via sidewall, wherein the housing is made from aluminum and the insulating sleeve is a layer of anodized aluminum.

8. The housing as in claim 7 comprising a portion of an antenna using a plurality of isolated electrical contacts.

13. The housing of claim 7 wherein the electrically conductive filler is a conductive ink.

9. 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 through drilling using a laser, the via including a first opening in a top surface of a portion of the housing, a second opening in an opposing bottom surface of the portion and at least one sidewall extending between the first opening and the second opening;

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.

10. The housing as in claim 9 wherein the via has a diameter between 20 and 200 microns.

11. The housing in claim 10 wherein the isolated electrical contact operates as an on/off switch.

14. The housing of claim 9 wherein the electrically conductive filler is a conductive ink.