Metalized dielectric substrates for EAS tags

• US 20050129842A1
• Filed: 12/17/2004
• Published: 06/16/2005
• Est. Priority Date: 05/02/2002
• Status: Active Grant

• Current Assignee: Thomas F. Burke
• Original Assignee: Thomas F. Burke
• Inventors: Burke, Thomas F.
• Granted Patent: US 7,113,131 B2
• Time in Patent Office: Days
• US Class Current: 427/116
• CPC Class Codes: G08B 13/2414 using inductive tags

Abstract

A metallized substrate, such as used to make a resonant circuit tag with inductive and capacitive elements in series, has a thin inorganic or polymeric dielectric layer formed on a metal layer. The inorganic layer may be formed by anodizing a surface of the metal layer. The organic layer may be formed by flexographic printing. In both cases, a via hole is formed through the dielectric layer. A second layer of very thin conductive metal is deposited on the dielectric layer and in the via hole. The substrate is subsequently patterned with an etch resist and then etched to form the inductor coil and the capacitor plates, which are interconnected via the metallized via hole.

Claims

1. A metalized dielectric substrate comprising:

a flexible substantially planar dielectric substrate having a thickness of no more than about 2.5 microns and a first side and a second side;

a first flexible planar conductive layer on said first side of said dielectric substrate wherein said first conductive layer is at least 10 microns thick; and

a second planar conductive layer on said second side of said dielectric substrate.

2. The metalized substrate of claim 1 wherein the dielectric substrate is an inorganic dielectric material.

3. The metalized substrate of claim 1 wherein the dielectric substrate is a polymeric dielectric material.

4. The metalized substrate of claim 1 wherein there is at least one conductive element connecting said second conductive layer to said first conductive layer.

5. The metalized substrate of claim 2 wherein the planar inorganic dielectric is alumina.

6. The metalized substrate of claim 4 wherein the planar inorganic dielectric is alumina.

7. The metalized substrate of claim 2 wherein the first conductive layer is aluminum foil or aluminized copper foil and the second conductive layer is copper or aluminum.

8. The metalized substrate of claim 4 wherein the first conductive layer is aluminum foil or aluminized copper foil and the second conductive layer is copper or aluminum.

9. The metalized substrate of claim 2 wherein the first conductive layer has an aluminum surface and wherein the dielectric substrate is an anodized layer on the first conductive layer.

10. The metalized substrate of claim 4 wherein the first conductive layer has an aluminum surface and wherein the dielectric substrate is an anodized layer on the first conductive layer.

11. The metalized substrate of claim 2 wherein the dielectric substrate is a sputtered layer on the first conductive layer and the first conductive layer is copper foil or aluminum foil.

12. The metalized substrate of claim 4 wherein the conductive element is a via hole through the dielectric substrate and containing material of the second conductive layer.

23. The metalized dielectric substrate of claim 3 wherein the first side of the dielectric layer is bonded to one side of the first conductive layer;

and

the second conductive layer is formed on the second side of said dielectric layer.

24. The metalized substrate of claim 23 wherein the material of the planar polymeric dielectric layer is selected from the group consisting of polystyrene;

polyethylene;

polypropylene;

their co-copolymers;

or a fluoropolymer.

25. The metalized substrate of claim 24 wherein the material of the planar polymeric dielectric layer is selected from the group consisting of polystyrene;

polyethylene;

polypropylene;

their co-copolymers;

or a fluoropolymer.

26. The metalized substrate of claim 23 wherein the first conductive layer is copper foil or aluminum foil and the second conductive layer is aluminum or copper.

27. The metalized dielectric substrate of claim 23 wherein the polymeric dielectric comprises at least two layers of different polymeric materials.

13. A resonant tag circuit for use as an electronic article surveillance tag, comprising:

a flexible substantially planar inorganic dielectric substrate having a thickness of no more than about 2.5 microns and a first side and a second side;

a conductive layer applied to said first side of said dielectric substrate wherein said conductive layer is at least 10 microns thick and a conductive layer applied to said second side of said dielectric substrate;

a first conductive pattern positioned on said first side of said dielectric substrate wherein said conductive pattern comprises an inductor and a capacitor plate;

a second conductive pattern positioned on said second side of said dielectric substrate wherein said conductive pattern comprises a capacitor plate in registration with said capacitor plate on said first side of said dielectric substrate;

a conductive element connecting said second conductive pattern to said first conductive pattern to form a series inductor-capacitor resonant circuit.

14. The resonant tag circuit of claim 13 wherein the conductive element is a via hole through the dielectric substrate and containing material of the conductive layer applied to said second side of the dielectric substrate.

15. The resonant tag circuit of claim 13 wherein the dielectric substrate is alumina, the conductive layer applied to the first side of the dielectric substrate is aluminum foil or aluminized copper foil and the conductive layer applied to the second side of the dielectric substrate is aluminum or copper.

16. The resonant tag circuit of claim 13 wherein the dielectric substrate is a composite of two or more layers of different inorganic materials.

17. The resonant tag circuit of claim 15 wherein the dielectric substrate is a composite of two or more layers of different inorganic materials.

18. The resonant tag circuit of claim 13 wherein multiple inductor and capacitor plate patterns are positioned on said first side of said dielectric and corresponding multiple capacitor plates are positioned in registration on said second side of said dielectric substrate.

19. The resonant tag circuit of claim 13 wherein one or more integrated circuit chips and other electronic components are electrically connected to the circuit patterns formed on either side of said dielectric.

20. The resonant tag circuit of claim 18 wherein one or more integrated circuit chips and other electronic components are electrically connected to the circuit patterns formed on either side of said dielectric.

21. The resonant tag circuit of claim 13 wherein the dielectric substrate is a sputtered layer on the first conductive layer, the conductive layer applied to the first side of the dielectric substrate is aluminum foil or copper foil and the conductive layer applied to the second side of the dielectric substrate is copper or aluminum.

22. The resonant tag circuit of claim 21 wherein the dielectric substrate is a composite of two or more layers of different inorganic materials.

28. A resonant tag circuit for use as an electronic article surveillance tag, comprising:

a first conductive layer at least 10 microns thick;

a flexible substantially planar polymeric dielectric layer having a thickness of no more than about 2.5 microns, a first side of the dielectric layer being bonded to one side of the first conductive layer;

a second conductive layer formed on a second side of said dielectric layer;

a first conductive pattern formed in said first conductive layer, said first conductive pattern comprising an inductor and a capacitor plate;

a second conductive pattern formed in said second conductive layer, said second conductive pattern comprising a capacitor plate in registration with said capacitor plate; and

a conductive element connecting said second conductive pattern to said first conductive pattern to form a series inductor-capacitor resonant circuit.

29. The resonant tag circuit of claim 28 wherein the dielectric layer comprises polystyrene, the first conductive layer comprises copper foil or aluminum foil, and the second conductive layer comprises copper or aluminum.

30. The resonant tag circuit of claim 28 wherein the dielectric layer is selected from the group consisting of polyethylene, polypropylene, one of their copolymers, or a fluoropolymer.

31. The resonant tag circuit of claim 28 wherein the second conductive layer comprises a conductive polymer.

32. The resonant tag circuit of claim 28 wherein multiple inductor and capacitor plate patterns are formed in the first conductive layer and corresponding multiple capacitor plates are formed in registration in the second conductive layer.

33. The resonant tag circuit of claim 28 wherein one or more integrated circuit chips and other electronic components are electrically connected to the circuit patterns formed in either the first or second conductive layers.

34. The resonant tag circuit of claim 32 wherein one or more integrated circuit chips and other electronic components are electrically connected to the circuit patterns formed in either the first or second conductive layers.

35. The resonant tag circuit of claim 28 wherein the polymeric dielectric layer comprises at least two layers of different polymeric materials.

36. The resonant tag circuit of claim 28 wherein the conductive element is a via hole through the dielectric layer and containing material of the second conductive layer.

37. For use in making a resonant tag circuit a metalized dielectric substrate comprising:

a flexible substantially planar dielectric substrate having a uniform thickness of no more than about 2.5 microns and a first side and a second side;

a first flexible planar conductive layer on said first side of said dielectric substrate wherein said first conductive layer has a uniform thickness of at least 10 microns; and

a second planar conductive layer of uniform thickness on said second side of said dielectric substrate.

38. The metalized substrate of claim 37 wherein there is at least one conductive element connecting said second conductive layer to said first conductive layer.

39. The metalized substrate of claim 38 wherein the dielectric substrate is an inorganic dielectric material.

40. The metalized substrate of claim 38 wherein the dielectric substrate is a polymeric dielectric material.

41. The metalized dielectric substrate of claim 38 wherein the conductive element is a via hole through the dielectric substrate and containing material of the second conductive layer.