Magnetic particle flow detector

• US 7,391,091 B2
• Filed: 09/29/2005
• Issued: 06/24/2008
• Est. Priority Date: 09/29/2004
• Status: Active Grant

• Current Assignee: NVE Corporation
• Original Assignee: NVE Corporation
• Inventors: Popple, Anthony D., Anderson, John M., Tondra, Mark C., Brownell, David J.
• Primary Examiner(s): Jackson; Jerome
• Assistant Examiner(s): Valentine; Jami M
• Application Number:
  US11/241,771
• Publication Number:
  US 20060081954A1
• Time in Patent Office: 999 Days
• Field of Search: 257/421, 257/427, 324/260, 360/713, 360/213, 365/8, 438/50
• US Class Current: 257/427
• CPC Class Codes: G01R 33/1276 of magnetic particles, e.g. imaging of magnetic nanoparticles G01R33/1269 takes precedence
• CPC Class Codes: G01V 3/08 operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices with electromagnetic waves G01V3/12
• CPC Class Codes: Y10S 977/932 for electronic or optoelectronic application
• CPC Class Codes: Y10S 977/933 Spintronics or quantum computing
• CPC Class Codes: Y10S 977/934 Giant magnetoresistance, GMR

Abstract

A ferromagnetic thin-film based magnetic field detection system having a substrate supporting a magnetic field sensor in a channel with a first electrical conductor supported on the substrate positioned at least in part along the channel gap and in direct contact with at least some surface of the magnetic field sensor ands a second electrical conductor supported on the substrate positioned at least in part along the channel gap in a region thereof adjacent to, but separated from, the magnetic field sensor.

Claims

1. A ferromagnetic thin-film based magnetic field detection system, said system comprising:

a substrate;

a magnetic field sensor supported on at least a portion of said substrate at a sensor location;

a channel base material supported on at least a portion of said substrate but without being across said magnetic field sensor from said substrate so as to form sides of an extended opening at said sensor location that extends past said magnetic field sensor in at least one direction to thereby form an extended channel gap in said channel base material across from at least a portion of said sensor location;

a first electrical conductor supported on said substrate positioned at least in part at said sensor location so as to be in direct contact with at least some surface of said magnetic field sensor; and

a second electrical conductor supported on said substrate positioned at least in part along, and between projections of said sides of, said channel gap in a region thereof to be across a selected distance, parallel to said substrate, from a side of said magnetic field sensor and without extending from said region along said channel gap beyond said side.

2. The system of claim 1 further comprising a plurality of electrical conductors supported on said substrate, including said second electrical conductor, positioned at least in part along said channel gap in a region thereof adjacent to, but separated from, said magnetic field sensor.

3. The system of claim 1 further comprising an electrical insulating layer supported on at least a portion of said substrate, and said channel base material being supported on at least a portion of said electrical insulating layer.

4. The system of claim 1 wherein said magnetic field sensor is a first magnetic field sensor and wherein said first magnetic field sensor is one of a plurality of magnetic field sensors supported on said substrate each having a pair of terminating regions between which occurs an electrical resistance having magnitudes dependent on magnetic fields occurring thereabout and with each of said plurality of magnetic field sensors being electrically connected at said pair of terminating regions thereof in a bridge circuit formed of two circuit branches each having circuit components including at least one of said plurality of magnetic field sensors electrically connected in series therein and with said circuit branches electrically connected in parallel between terminals suited for electrical connection to a source of electrical energy.

5. The system of claim 3 wherein said channel base material is a polymeric material.

6. The system of claim 3 wherein said magnetic field sensor is substantially covered by said electrical insulating layer.

7. The system of claim 3 wherein said electrical insulating layer is a first electrical insulating layer upon which said magnetic field sensor is supported, and further comprising a second electrical insulating layer substantially on at least a portion of said first electrical insulating layer with said magnetic field sensor being substantially covered by said second electrical insulating layer.

8. The system of claim 3 wherein said polymeric channel base material is an electrical insulating material.

9. The system of claim 3 further comprising a bonding material supported on a side of said channel base material opposite said electrical insulating layer.

10. The system of claim 9 wherein said channel base material is enclosed about said magnetic field sensor except for channel gaps therein extending toward said substrate from that said side thereof supporting said bonding material including said extended channel gap, and further comprising a lid affixed to said bonding material.

11. The system of claim 1 wherein said second electrical conductor extends in part in a direction that parallels that direction in which said channel gap portion thereabout extends and extends in part in a direction that is at angle to that direction in which said channel gap portion thereabout extends.

12. The system of claim 1 wherein said second electrical conductor extends from an initial position in said channel gap to be positioned in a first paralleling zone of said channel gap, and in an adjacent diverging zone of said channel gap, and thereafter in a second paralleling zone adjacent to said diverging zone;

said second conductor (a) first extending from said initial position in part through said first paralleling zone in a direction that parallels that direction in which said channel gap portion thereabout extends, and (b) next extending in part through said diverging zone in a direction that is at angle to that direction in which said channel gap portion thereabout extends, and (c) next extending in part through said second paralleling zone in a direction that parallels that direction in which said channel gap portion thereabout extends, and (d) next extending further in part through said second paralleling zone through three direction reversals to form two adjacent semi-enclosed, partial loops, and (e) next extending in part through said diverging zone toward said first paralleling zone in a direction that is at angle to that direction in which said channel gap portion thereabout extends, and (f) next extending in part through said first paralleling zone in a direction that parallels that direction in which said channel gap portion thereabout extends, and (g) next extending further in part through said first paralleling zone through a direction reversal to another semi-enclosed, partial loop, and (h) next extending in part through said diverging zone in a direction that is at angle to that direction in which said channel gap portion thereabout extends, and (i) next extending in part through said second paralleling zone in a direction that parallels that direction in which said channel gap portion thereabout extends.

13. The system of claim 1 wherein said magnetic field sensor is formed of materials in an oblong layered structure, and said first electrical conductor is in contact with a substantial fraction of a surface of said oblong layered structure.

14. The system of claim 1 wherein said magnetic field sensor is formed in an oblong structure extending in a direction that parallels that direction in which said channel gap portion thereabout extends and said second electrical conductor extends at least in part in that direction so as to have that part thereof substantially aligned with said magnetic field sensor along said channel gap portion.

15. The system of claim 1 wherein said channel base material, enclosed about said magnetic field sensor except for channel gaps therein extending toward said substrate from that said side thereof opposite said substrate, has a primary channel gap extending in a selected direction and opens to a diverter channel gap extending away from said primary channel gap at an angle with respect to said selected direction.

16. The system of claim 1 wherein said channel base material, enclosed about said magnetic field sensor except for channel gaps therein extending toward said substrate from that said side thereof opposite said substrate, has a primary channel gap extending in a selected direction and opens across at least a part of a cross section thereof to a first diverter channel gap extending away from said primary channel gap at an angle with respect to said selected direction.

17. The system of claim 1 further comprising a third electrical conductor as an interconnection electrical conductor supported on said substrate in addition to said second electrical conductor and with said third electrical conductor extending at least in part substantially perpendicularly to said second electrical conductor but conductively interconnected with said second electrical conductor at one end thereof.

18. The system of claim 1 further comprising a third electrical conductor supported on said substrate positioned at least in part along said channel gap in a region thereof adjacent to, but separated from, said second electrical conductor such that said second electrical conductor is positioned between those positions taken by said magnetic field sensor and said third electrical conductor along said channel gap.

19. The system of claim 1 further comprising a channel side electrical conductor supported in said channel base material on said substrate at least in part along and adjacent to said channel gap between said substrate and a side of said channel base material opposite said substrate.

20. The system of claim 1 further comprising a fluid located in said channel gap in which relatively small material particles are present.

21. The system of claim 2 wherein said second electrical conductor extends in part in a direction that parallels that direction in which said channel portion thereabout extends and extends in part in a direction that is at angle to that direction in which said channel portion thereabout extends.

22. The system of claim 2 wherein said plurality of electrical conductors further comprises a third electrical conductor positioned at least in part along said channel gap parallel to, but separated from, said second electrical conductor.

23. The system of claim 4 wherein said first magnetic field sensor is formed of materials in an oblong layered structure, and said first electrical conductor is in contact with a substantial fraction of a surface of said oblong layered structure as one of said pair of terminating regions thereof.

24. The system of claim 4 wherein said first magnetic field sensor is formed in an oblong structure extending in a direction that parallels that direction in which said channel gap portion thereabout extends and said second electrical conductor extends at least in part in that direction so as to have that part thereof substantially aligned with said first magnetic field sensor along said channel gap portion.

25. The system of claim 4 wherein said two circuit branches each have two of said plurality of magnetic field sensors electrically connected in series therein.

26. The system of claim 11 wherein said second electrical conductor extends in a first part in a direction that parallels that direction in which said channel gap portion thereabout extends, and extends in a second part in a direction that is at angle to that direction in which said channel gap portion thereabout extends, and also extends in a third part in a direction that is at a different angle to that direction in which said channel gap portion thereabout extends than said angle at which said second part extends with said first, second and third parts meeting at a common junction.

27. The system of claim 11 further comprising a third electrical conductor supported on said substrate in addition to said second electrical conductor as an interconnection electrical conductor and extending at least in part substantially perpendicularly to said second conductor but conductively interconnected with said second electrical conductor at one end thereof.

28. The system of claim 15 further comprising a channel side electrical conductor supported in said channel base material on said substrate at least in part along and adjacent to said channel gap between said substrate and a side of said channel base material opposite said substrate.

29. The system of claim 16 wherein said channel base material, enclosed about said magnetic field sensor except for channel gaps therein extending toward said substrate from that said side thereof opposite said substrate, has said primary channel gap opening across at least another part of a cross section thereof to a second diverter channel gap extending away from said primary channel gap at an angle with respect to said selected direction.

30. The system of claim 17 further comprising a plurality of interconnection electrical conductors supported on said substrate, including said third electrical conductor, such that said plurality of interconnection electrical conductors are conductively interconnected with said second electrical conductor at one end thereof.

31. The system of claim 18 further comprising fourth and fifth electrical conductors as interconnection electrical conductors supported on said substrate in addition to said second and third electrical conductors with said fourth electrical conductor extending at least in part substantially perpendicularly to said second electrical conductor but conductively interconnected with said second electrical conductor at one end thereof, and with said fifth electrical conductor extending at least in part substantially perpendicularly to said third electrical conductor but conductively interconnected with said third electrical conductor at one end thereof.

32. The system of claim 19 wherein said channel side electrical conductor is a first channel side electrical conductor further comprising a second channel side electrical conductor supported in said channel base material on said substrate at least in part along and adjacent to said channel gap across said channel gap from said first channel side electrical conductor and between said substrate and a side of said channel base material opposite said substrate.

33. The system of claim 20 wherein at least some of said material particles are paramagnetic material particles.

34. The system of claim 20 wherein at least some of said material particles are magnetic material particles that are linearly magnetizable.

35. The system of claim 20 wherein at least some of said material particles are superparamagnetic material particles.

36. The system of claim 20 wherein at least some of said material particles are magnetic material particles that are substantially of a spherical shape.

37. The system of claim 20 wherein at least some of said material particles are magnetic material particles that are substantially of an ellipsoidal shape.

38. The system of claim 20 wherein at least some of said material particles are magnetic material particles that are substantially of a rectangular solid shape.

39. The system of claim 20 wherein at least some of said material particles are coated at least in part with another kind of material.

40. The system of claim 20 wherein at least some of said material particles are magnetic material particles and further comprising said fluid having therein electrically polarizable material particles.

41. The system of claim 20 wherein at least some of said material particles are magnetic material particles and further comprising said fluid having therein electrically charged particles.

42. The system of claim 21 wherein another of said plurality of electrical conductors extends in part in a direction that parallels that direction in which said channel portion thereabout extends and extends in part in a direction that is at angle to that direction in which said channel portion thereabout extends to thereby parallel similarly extending parts of said second electrical conductor.

43. The system of claim 22 further comprising a fourth electrical conductor as an interconnection electrical conductor supported on said substrate in addition to said second and third electrical conductors and with said fourth electrical conductor extending at least in part substantially perpendicularly to said second and third electrical conductors but conductively interconnected with said second and third electrical conductors at one end of each.

44. The system of claim 25 wherein said first magnetic field sensor is formed of materials in an oblong layered structure, and said first electrical conductor is in contact with a substantial fraction of a surface of said oblong layered structure as one of said pair of terminating regions thereof.

45. The system of claim 25 wherein all four of said plurality of magnetic field sensors electrically connected in said two circuit branches are positioned side by side parallel to one another but with each separated along a separation direction from any adjacent one thereof such that said separation direction is substantially perpendicular to that direction in which said channel portion thereabout extends.

46. The system of claim 27 further comprising a plurality of interconnection electrical conductors supported on said substrate, including said third electrical conductor, such that said plurality of interconnection electrical conductors are conductively interconnected with said second electrical conductor at one end thereof.

47. The system of claim 28 wherein said channel side electrical conductor is a first channel side electrical conductor further comprising a second channel side electrical conductor supported in said channel base material on said substrate at least in part along and adjacent to said channel gap across said channel gap from said first channel side electrical conductor and between said substrate and a side of said channel base material opposite said substrate.

48. The system of claim 29 wherein said second electrical conductor extends from an initial position in said primary channel gap to be positioned in a first diverging zone of said channel gap, and in an adjacent first paralleling zone of said primary channel gap, and thereafter in a partially paralleling zone of said primary channel gap adjacent to said first paralleling zone, and next in a second diverging zone of said primary channel gap adjacent to said partially paralleling zone, and finally in a second paralleling zone of said first and second diverting channel gaps adjacent to said second diverging zone;

said second conductor (a) first extending from said initial position in part through said first diverging zone in a direction that is at least at one angle to that direction in which said primary channel gap portion thereabout extends, and (b) next extending in part through said first and said partial paralleling zones in a direction that parallels that direction in which said primary channel gap portion thereabout extends, and (c) next extending in part through said second diverging zone in a direction that is at least at one angle to that direction in which said primary channel gap portion just previously extended, and (d) finally extending in part through said second paralleling zone in a direction that parallels that direction in which said diverting channel gap portion thereabout extends;

a third conductor (a) first extending from an initial position thereof in part through said first diverging zone in a direction that is at least at one angle to that direction in which said primary channel gap portion thereabout extends, and (b) next extending in part through said first and said partial paralleling zones in a direction that parallels that direction in which said primary channel gap portion thereabout extends, and (c) next extending in part through said second diverging zone in a direction that is at least at one angle to that direction in which said primary channel gap portion just previously extended, and (d) finally extending in part through said second paralleling zone in a direction that parallels that direction in which said primary channel gap portion previously extended;

a fourth conductor (a) first extending from an initial position thereof in part through said first paralleling zone in a direction that parallels that direction in which said primary channel gap portion thereabout extends, and (b) next extending in part through said partial paralleling zone in a direction that is at least at one angle to that direction in which said primary channel gap portion thereabout extends, and (c) next extending in part through said second diverging zone in a direction that is at least at one angle to that direction in which said primary channel gap portion just previously extended, and (d) finally extending in part through said second paralleling zone in a direction that parallels that direction in which said diverting channel gap portion thereabout extends.

49. The system of claim 31 wherein said magnetic field sensor is formed in an oblong structure extending in a direction that parallels that direction in which said channel gap portion thereabout extends and said second electrical conductor extends at least in part in that direction so as to have that part thereof substantially aligned with said magnetic field sensor along said channel gap portion.

50. The system of claim 40 further comprising an electrostatic detector provided at said channel gap.

51. The system of claim 41 further comprising an electrostatic detector provided at said channel gap.

52. The system of claim 45 further comprising a plurality of electrical conductors supported on said substrate, including said second electrical conductor, positioned at least in part along said channel gap in a region thereof adjacent to, but separated from, said magnetic field sensor wherein said plurality of electrical conductors comprises four electrical conductors positioned at least in part along said channel gap parallel to, but separated from, said second electrical conductor therein with said four electrical conductors each being aligned with a corresponding one of said four of said plurality of magnetic field sensors.

53. The system of claim 49 wherein said third electrical conductor extends at least in part in said direction in which said second electrical conductor extends so as to have that part thereof substantially aligned with said second electrical conductor along said channel gap portion.