Magnetically shielded assembly

• US 6,713,671 B1
• Filed: 11/25/2002
• Issued: 03/30/2004
• Est. Priority Date: 01/22/2002
• Status: Expired due to Fees

• Current Assignee: Biophan Technologies Incorporated
• Original Assignee: Nanoset LLC
• Inventors: MacDonald, Stuart G., Helfer, Jeffrey L., Wang, Xingwu
• Primary Examiner(s): Ngo, Hung V.
• Application Number:
  US10/303,264
• Time in Patent Office: 491 Days
• Field of Search: 174/35.R, 174/35.MS, 361/816, 361/818, 361/800, 428/217, 428/219, 428/218
• US Class Current: 174/391
• CPC Class Codes: A61N 1/16 Screening or neutralising undesirable influences from or using, atmospheric or terrestrial radiation or fields using atmospheric electricity or earth currents H05F3/00
• CPC Class Codes: B82Y 25/00 Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance
• CPC Class Codes: H01B 11/10 Screens specially adapted for reducing interference from external sources
• CPC Class Codes: H01B 11/1083 the coating containing magnetic material
• CPC Class Codes: H01F 1/0063 in a non-magnetic matrix, e.g. granular solids granular films H01F10/007
• CPC Class Codes: H01F 10/007 ultrathin or granular films H01F10/005 and H01F10/3227 take precedence; applying ultrathin or granular layers to substrates H01F41/301
• CPC Class Codes: H01F 10/324 Exchange coupling of magnetic film pairs via a very thin non-magnetic spacer, e.g. by exchange with conduction electrons of the spacer
• CPC Class Codes: Y10T 428/24983 Hardness
• CPC Class Codes: Y10T 428/24992 Density or compression of components

Abstract

A shielded assembly containing a substrate and a shield. The shield contains both nanomagnetic material and a material with an electrical resistivity of from about 1 microohm-centimeter to about 1×10²⁵ microohm centimeters. The nanomagnetic material has a mass density of at least about 0.01 grams per cubic centimeter, a saturation magnetization of from about 1 to about 36,000 Gauss, a coercive force of from about 0.01 to about 5000 Oersteds, a relative magnctic permeability of from about 1 to about 500,000, and an average particle size of less than about 100 nanometers.

Claims

1. A shielded assembly comprised of a substrate and, disposed above said substrate, a shield, wherein said shield is comprised of from about 1 to about 99 weight percent of a first nanomagnetic material, and from about 99 to about 1 weight percent of a second material with an electrical resistivity of from about 1 microohm-centimeter to about 1×

10²⁵ microohm centimeters, and wherein said nanomagnetic material has a mass density of at least about 0.01 grams per cubic centimeter, a saturation magnetization of from about 1 to about 36,000 Gauss, a coercive force of from about 0.01 to about 5000 Oersteds, a relative magnetic permeability of from about 1 to about 500,000, and an average particle size of less than about 100 nanometers.

2. The shielded assembly as recited in claim 1, wherein said shield is contiguous with said substrate.

3. The shielded assembly as recited in claim 1, wherein said substrate is a foil.

4. The shielded assembly as recited in claim 1, wherein said substrate is comprised of ceramic material.

5. The shielded assembly as recited in claim 1, wherein said substrate is comprised of glass.

6. The shielded assembly as recited in claim 1, wherein said substrate is in the form of a cyulinder.

7. The shielded assembly as recited in claim 1, wherein said substrate is in the shape of a sphere.

8. The shielded assembly as recited in claim 1, wherein said substrate has a thickness of from about 100 nanometers to about 2 centimeters.

9. The shielded assembly as recited in claim 1, wherein said substrate is flexible.

10. The shielded assembly as recited in claim 1, wherein said shield is comprised of at least about 40 weight percent of said nanomagnetic material.

11. The shielded assembly as recited in claim 1, wherein said shield is comprised of at least about 50 weight percent of said nanomagnetic material.

12. The shielded assembly as recited in claim 10, wherein said shield is comprised of from about 40 to about 60 weight percent of said second material with an electrical resistivity of from about 1 microohm-centimeter to about 1×

10²⁵ microohm centimeters.

13. The shielded assembly as recited in claim 12, wherein said second material with an electrical resistivity of from about 1 microohm-centimeter to about 1×

10²⁵ microohm centimeters has a dielectric constant of from about 1 to about 50.

14. The shielded assembly as recited in claim 12, wherein said second material with an electrical resistivity of from about 1 microohm-centimeter to about 1×

10²⁵ microohm centimeters has a dielectric constant of from about 1.1 to about 10.

15. The shielded assembly as recited in claim 12, wherein said second material with an electrical resistivity of from about 1 microohm-centimeter to about 1×

10²⁵ microohm centimeters has a particle size of from about 5 to about 100 nanometers.

16. The shielded assembly as recited in claim 12, wherein said second material with an electrical resistivity of from about 1 microohm-centimeter to about 1×

10²⁵ microohm centimeters has an elongated shape with an aspect ratio of at least about 10.

17. The shielded assembly as recited in claim 16, wherein said second material with an electrical resistivity of from about 1 microohm-centimeter to about 1×

10²⁵ microohm centimeters is comprised of a multiplicity of aligned fibers.

18. The shielded assembly as recited in claim 12, wherein said second material with an electrical resistivity of from about 1 microohm-centimeter to about 1×

10²⁵ microohm centimeters is comprised of a multiplicity of filaments, and wherein each filament is comprised of a metal and an essentially coaxial core.

19. The shielded assembly as recited in claim 18, wherein each of said filaments has a diameter less than about 6 microns.

20. The shielded assembly as recited in claim 19, wherein each of said coaxial cores is comprised essentially of carbon.

21. The shielded assembly as recited in claim 12, wherein said second material with an electrical resistivity of from about 1 microohm-centimeter to about 1×

10²⁵ microohm centimeters is a particulate carbon complex.

22. The shielded assembly as recited in claim 21, wherein said particulate carbon complex is comprised of a carbon black substrate and a plurality of carbon filaments.

23. The shielded assembly as recited in claim 12, wherein said second material with an electrical resistivity of from about 1 microohm-centimeter to about 1×

10²⁵ microohm centimeters is a diamond like carbon material with a Mohs hardness of from about 2 to about 15.

24. The shielded assembly as recited in claim 12, wherein said second material with an electrical resistivity of from about 1 microohm-centimeter to about 1×

10²⁵ microohm centimeters is a diamond like carbon material with a Mohs hardness of from about 5 to about 15.

25. The shielded assembly as recited in claim 12, wherein said second material with an electrical resistivity of from about 1 microohm-centimeter to about 1×

10²⁵ microohm centimeters is a carbon nanotube material.

26. The shielded assembly as recited in claim 12, wherein said second material with an electrical resistivity of from about 1 microohm-centimeter to about 1×

10²⁵ microohm centimeters is selected from the group consisting of silicon dioxide, aluminum nitride, cerium oxide, yttrium dioxide, and mixtures thereof.

27. The shielded assembly as recited in claim 26, wherein said second material with an electrical resistivity of from about 1 microohm-centimeter to about 1×

10²⁵ microohm centimeters has a particle size of form about 10 to about 100 nanometers.

28. The shielded assembly as recited in claim 1, wherein said shield is in the form of a layer material comprised of said first nanomagnetic material and said second material with an electrical resistivity of from about 1 microohm-centimeter to about 1×

10²⁵ microohm centimeters.

29. The shielded assembly as recited in claim 1, wherein said shield is comprised of a first layer comprising said nanomagnetic material and a second layer comprised of said second material with an electrical resistivity of from about 1 microohm-centimeter to about 1×

10²⁵ microohm centimeters.

30. The shielded assembly as recited in claim 29, wherein said first layer is disposed between said substrate and said second layer.

31. The shielded assembly as recited in claim 29, wherein said second layer is disposed between said substrate and said first layer.

32. The shielded assembly as recited in claim 1, wherein said shield has an electromagnetic shielding factor of at least about 0.9.