Metal Deposition

• US 20100044079A1
• Filed: 10/29/2009
• Published: 02/25/2010
• Est. Priority Date: 08/27/1999
• Status: Abandoned Application

• Current Assignee: Littelfuse Incorporated
• Original Assignee: Littelfuse Incorporated
• Inventors: Kosowsky, Lex
• Application Number:
  US12/608,315
• Publication Number:
  US 20100044079A1
• Time in Patent Office: Days
• US Class Current: 174/250
• CPC Class Codes: C25D 5/022 using masking means
• CPC Class Codes: C25D 5/56 of plastics
• CPC Class Codes: H05K 1/0257 Overvoltage protection
• CPC Class Codes: H05K 1/0259 Electrostatic discharge [ESD] protection
• CPC Class Codes: H05K 1/0373 containing additives, e.g. fillers H05K1/036 takes precedence
• CPC Class Codes: H05K 1/0393 Flexible materials H05K1/038 takes precedence; specific organic compositions are classified in H05K1/0313 and subgroups
• CPC Class Codes: H05K 1/056 the metal substrate being covered by an organic insulating layer
• CPC Class Codes: H05K 2201/0215 Metallic fillers
• CPC Class Codes: H05K 2201/0738 Use of voltage responsive materials, e.g. voltage switchable dielectric or varistor materials
• CPC Class Codes: H05K 2203/0557 Non-printed masks
• CPC Class Codes: H05K 2203/1168 Graft-polymerization
• CPC Class Codes: H05K 2203/1492 Periodical treatments, e.g. pulse plating of through-holes
• CPC Class Codes: H05K 3/07 being removed electrolytically
• CPC Class Codes: H05K 3/188 by direct electroplating
• CPC Class Codes: H05K 3/423 characterised by electroplating method
• CPC Class Codes: H05K 3/426 initial plating of through-holes in substrates without metal
• CPC Class Codes: H05K 3/4644 by building the multilayer layer by layer, i.e. build-up multilayer circuits making via holes in the insulating layers H05K3/0011; special circuit boards as base or core whereon the multilayer is built H05K3/4602

Abstract

Systems and methods include depositing one or more materials on a voltage switchable dielectric material. In certain aspects, a voltage switchable dielectric material is disposed on a conductive backplane. In some embodiments, a voltage switchable dielectric material includes regions having different characteristic voltages associated with deposition thereon. Some embodiments include masking, and may include the use of a removable contact mask. Certain embodiments include electrografting. Some embodiments include an intermediate layer disposed between two layers.

Claims

1. A method for fabricating a current-carrying formation, the method comprising:

providing a voltage switchable dielectric material having a characteristic voltage;

applying a contact mask to a surface of the voltage switchable dielectric material, the contact mask including;

an insulating foot that contacts the surface and defines a portion of the surface for deposition, and

an electrode, separated from the surface by the foot;

immersing the voltage switchable dielectric material and applied contact mask in a solution that provides a source of ions associated with an electrical conductor to the defined portion; and

depositing the electrical conductor onto the defined portion of the surface of the voltage switchable dielectric material.

2. The method of claim 1, wherein depositing includes creating a voltage between the electrode and the voltage switchable dielectric material that is greater than the characteristic voltage.

3. The method of claim 2, wherein the voltage includes a cyclic voltage.

4. The method of claim 2, wherein the voltage includes a voltage between 2 and 200 volts.

5. The method of claim 1, wherein the voltage switchable dielectric material includes a via, and depositing includes depositing in the via.

6. The method of claim 1, wherein depositing includes electroplating.

7. The method of claim 1, wherein the insulating foot includes a polymer.

8. The method of claim 1, wherein the insulating foot includes a photoresist.

9. The method of claim 1, wherein the electrode is separated from the surface by a distance of less than 2 cm.

10. The method of claim 9, wherein the electrode is separated from the surface by a distance of less than 2 mm.

11. The method of claim 1, wherein providing includes providing the voltage switchable dielectric material on a conductive backplane.

12. The method of claim 1, wherein providing includes providing the voltage switchable dielectric material with an intermediate layer disposed on the surface.

13. A method for fabricating a current-carrying formation, the method comprising:

providing an electrically conductive material on a voltage switchable dielectric material having a characteristic voltage;

applying a contact mask to a surface of the electrically conductive material, the contact mask including;

an insulating foot that contacts the surface and defines a portion of the surface for etching, and

an electrode, separated from the surface by the foot;

immersing the voltage switchable dielectric material, deposited electrically conductive material and applied contact mask in an electrochemical etching solution; and

etching the electrically conductive material from the defined portion of the surface.

14. The method of claim 13, wherein etching includes creating a voltage between the electrode and the voltage switchable dielectric material that is greater than the characteristic voltage.

15. The method of claim 14, wherein the electrochemical etching solution does not etch the conductive material when the voltage is less than the characteristic voltage.

16. The method of claim 13, wherein the electrically conductive material includes a metal.

17. The method of claim 13, wherein the insulating foot includes a polymer.

18. The method of claim 13, wherein the electrically conductive material includes any of Cu, Ti, Ta, Au, and Ag.

19. The method of claim 13, wherein the electrode is separated from the surface by a distance of less than 2 cm.

20. The method of claim 19, wherein the electrode is separated from the surface by a distance of less than 1 mm.

21. The method of claim 14, wherein creating the voltage includes creating a cyclic voltage.

22. The method of claim 14, wherein the voltage is between 1 and 300 volts.

23. The method of claim 13, wherein providing includes providing the voltage switchable dielectric material on a conductive backplane.

24. The method of claim 13, wherein providing includes providing the voltage switchable dielectric material with an intermediate layer disposed on at least a portion of the surface.

25. A current-carrying formation fabricated using a method comprising:

providing a voltage switchable dielectric material having a characteristic voltage;

applying a contact mask to a surface of the voltage switchable dielectric material, the contact mask including;

an insulating foot that contacts the surface and defines a portion of the surface for deposition, and

an electrode, separated from the surface by the foot;

immersing the voltage switchable dielectric material and applied contact mask in a solution that provides a source of ions associated with an electrical conductor to the defined portion; and

depositing the electrical conductor onto the defined portion of the surface of the voltage switchable dielectric material.

26. A current-carrying formation fabricated using a method comprising:

providing an electrically conductive material on a voltage switchable dielectric material having a characteristic voltage;

applying a contact mask to a surface of the electrically conductive material, the contact mask including;

an insulating foot that contacts the surface and defines a portion of the surface for etching, and

an electrode, separated from the surface by the foot;

immersing the voltage switchable dielectric material, deposited electrically conductive material and applied contact mask in an electrochemical etching solution; and

etching the electrically conductive material from the defined portion of the surface.