Electromagnetic noise suppressing thin film
View Patent ↗An electromagnetic noise suppressing thin film has a structure including an inorganic insulating matrix made of oxie, nitride, fluoride, or a mixture thereof and columnar-structured particles made of a pure metal of Fe, Co, or Ni or an alloy containing at least 20 weight % of Fe, Co, or Ni and buried in an inorganic insulating matrix.
1. An electromagnetic noise suppressing thin film having a structure including an inorganic insulating matrix made of oxide, nitride, fluoride, or a mixture thereof and columnar-structured particles made of a pure metal of Fe, Co, or Ni or an alloy containing at least 20 weight % of Fe, Co, or Ni and buried in the inorganic insulating matrix, and each columnar-structured particle has an easy magnetization axis in a longitudinal direction thereof and a plurality of the columnar-structured particles are arranged substantially parallel to one another in a diameter direction via the insulating matrix to form a repetitive structure, the columnar-structured particles having a dimension ratio L/D, where L represents the length of the columnar-structured particle and D represents the width of the columnar-structured particle, in the range of 1<L/D<1000.
2. The electromagnetic noise suppressing thin film according to claim 1 , wherein the columnar-structured particles are made of a metal having a composition of Ni x Fe (100-x) alloy (75<x<85 at %), iron, or a composition of Fe y Co (100-y) alloy (50<y<70 at %).
3. The electromagnetic noise suppressing thin film according to claim 1 , wherein L/D is in the range of 100≦L/D≦1000.
4. The electromagnetic noise suppressing thin film according to claim 1 , wherein the thickness of the insulating matrix present in a gap between columnar-structured particles is in the range of 1 nm to 1000 nm.
5. The electromagnetic noise suppressing thin film according to claim 1 , wherein each columnar-structured particle has an easy magnetization axis in a longitudinal direction thereof and a plurality of the columnar-structured particles are arranged to be stacked on one another in the longitudinal direction via the inorganic insulating matrix to form a repetitive structure.
6. The electromagnetic noise suppressing thin film according to claim 5 , wherein, in the longitudinal direction of the columnar-structured particles, a gap between every adjacent ones of the columnar-structured particles or a thickness of the insulating matrix present in the gap is in the range of 1 nm to 1000 nm.
7. The electromagnetic noise suppressing thin film according to claim 5 , wherein the electromagnetic noise suppressing thin film comprises a plurality of columnar structure layers stacked on one another, each of the columnar structure layers being a magnetic layer comprising the columnar-structured particles different in dimension ratio L/D, where L represents the length of the columnar-structured particle and D represents the width of the columnar-structured particle, from those in the other columnar structure layers.
8. The electromagnetic noise suppressing thin film according to claim 7 , wherein the magnetic layers comprising the columnar-structured particles different in dimension ratio L/D are stacked on one another via the insulating matrix having a thickness t, the electromagnetic noise suppressing thin film having a plurality of different magnetic resonance frequencies equal to or smaller in number than the number of the magnetic layers.
9. The electromagnetic noise suppressing thin film according to claim 1 , wherein a saturation magnetostrictive constant of the electromagnetic noise suppressing thin film has an absolute value |λ s | within the range of |λ s |<60 ppm.
10. The electromagnetic noise suppressing thin film according to claim 1 , wherein the electromagnetic noise suppressing thin film has a d.c. resistivity within the range of 10 2 to 10 9 μΩcm.
11. The electromagnetic noise suppressing thin film according to claim 1 , wherein the electromagnetic noise suppressing thin film has a d.c. resistivity within the range of 10 4 to 10 7 μΩcm.
12. The electromagnetic noise suppressing thin film according to claim 1 , wherein a longitudinal direction of the columnar-structured particles is substantially parallel to a thickness direction of the electromagnetic noise suppressing thin film.
13. The electromagnetic noise suppressing thin film according to claim 1 , wherein a longitudinal direction of the columnar-structured particles is inclined by an average angle θ with respect to a thickness direction of the electromagnetic noise suppressing thin film, the average angle φ falling within the range of 0≦φ≦90°.
14. The electromagnetic noise suppressing thin film according to claim 1 , wherein a longitudinal direction of the columnar-structured particles is inclined by an average angle φ with respect to a thickness direction of the electromagnetic noise suppressing thin film, the average angle f falling within the range of 45≦φ≦90°.
15. The electromagnetic noise suppressing thin film according to claim 1 , wherein a longitudinal direction of the columnar-structured particles is inclined by an average angle φ with respect to a thickness direction of the electromagnetic noise suppressing thin film, the average angle f falling within the range of 80<φ≦90°.
16. A circuit board including an interconnection line provided with the electromagnetic noise suppressing thin film according to claim 1 .
17. An electromagnetic noise suppressing thin film having a structure including an inorganic insulating matrix made of oxide, nitride, fluoride, or a mixture thereof and columnar-structured particles made of a pure metal of Fe, Co, or Ni or an alloy containing at least 20 weight % of Fe, Co, or Ni and buried in the inorganic insulating matrix, wherein the columnar-structured particles exhibit a single-domain behavior, and each columnar-structured particle has an easy magnetization axis in a longitudinal direction thereof and a plurality of the columnar-structured particles are arranged substantially parallel to one another in a diameter direction via the insulating matrix to form a repetitive structure, the columnar-structured particles having a dimension ratio L/D, where L represents the length of the columnar-structured particle and D represents the width of the columnar-structured particle, in the range of 1<L/D<1000.
18. The electromagnetic noise suppressing thin film according to claim 17 , wherein the columnar-structured particles are made of a metal having a composition of Ni x Fe (100-x) alloy (75≦x≦85 at %), iron, or a composition of Fe y Co (100-y) alloy (50≦y≦70 at %).
19. The electromagnetic noise suppressing thin film according to claim 17 , wherein a thickness of the insulating matrix present in a gap between adjacent columnar-structured particles is in the range of 1 nm to 1000 nm.
20. The electromagnetic noise suppressing thin film according to claim 17 , wherein each columnar-structured particle has an easy magnetization axis in a longitudinal direction thereof and a plurality of the columnar-structured particles are arranged substantially parallel to one another in a diameter direction via the insulating matrix to form a repetitive structure.
21. The electromagnetic noise suppressing thin film according to claim 20 , wherein a gap between every adjacent ones of the columnar-structured particles in the diameter direction of the columnar-structured particles or a thickness of the insulating matrix present in the gap is in the range of 1 nm to 1000 nm.
22. The electromagnetic noise suppressing thin film according to claim 20 , wherein, in the diameter direction of the columnar-structured particles, a gap between every adjacent ones of the columnar-structured particles or a thickness of the insulating matrix present in the gap is in the range of 1 nm to 100 nm.
23. The electromagnetic noise suppressing thin film according to claim 20 , wherein the electromagnetic noise suppressing thin film comprises a plurality of columnar structure layers stacked on one another, each of the columnar structure layers being a magnetic layer comprising the columnar-structured particles different in dimension ratio L/D, where L represents the length of the columnar-structured particle and D represents the width of the columnar-structured particle, from those in the other columnar structure layers.
24. The electromagnetic noise suppressing thin film according to claim 17 , wherein a saturation magnetostriction constant of the electromagnetic noise suppressing thin film has an absolute value |λ s | within the range of |λ s |≦60 ppm.
25. The electromagnetic noise suppressing thin film according to claim 17 , wherein the electromagnetic noise suppressing thin film has a d.c. resistivity within the range of 10 2 to 10 9 μΩcm.
26. The electromagnetic noise suppressing thin film according to claim 17 , wherein the electromagnetic noise suppressing thin film has a d.c. resistivity within the range of 10 4 to 10 7 μΩcm.
27. The electromagnetic noise suppressing thin film according to claim 17 , wherein a longitudinal direction of the columnar-structured particles is substantially parallel to a thickness direction of the electromagnetic noise suppressing thin film.
28. The electromagnetic noise suppressing thin film according to claim 27 , wherein the magnetic layers comprising the columnar-structured particles different in dimension ratio L/D are stacked on one another via the insulating matrix having a thickness t, the electromagnetic noise suppressing thin film having a plurality of different magnetic resonance frequencies equal to or smaller in number than the number of the magnetic layers.
29. The electromagnetic noise suppressing thin film according to claim 17 , wherein a longitudinal direction of the columnar-structured particles is inclined by an average angle φ with respect to a thickness direction of the electromagnetic noise suppressing thin film, the average angle φ falling within the range of 0<φ<90°.
30. A circuit board including an interconnection line provided with the electromagnetic noise suppressing thin film according to claim 17 .
31. An electromagnetic noise suppressing thin film having a structure including an inorganic insulating matrix made of oxide, nitride, fluoride, or a mixture thereof and columnar-structured particles made of a pure metal of Fe, Co, or Ni or an alloy containing at least 20 weight % of Fe, Co, or Ni and buried in the inorganic insulating matrix, and each columnar-structured particle has an easy magnetization axis in a longitudinal direction thereof and a plurality of the columnar-structured particles are arranged substantially parallel to one another in a diameter direction via the insulating matrix to form a repetitive structure, wherein the columnar-structured particles are made of a metal having a composition of Ni x Fe (100-x) alloy (75≦x≦85 at %), iron, or a composition of Fe y Co (100-y) alloy (50≦y≦70 at %).
32. An electromagnetic noise suppressing thin film having a structure including an inorganic insulating matrix made of oxide, nitride, fluoride, or a mixture thereof and columnar-structured particles made of a pure metal of Fe, Co, or Ni or an alloy containing at least 20 weight % of Fe, Co, or Ni and buried in the Inorganic insulating matrix, wherein the columnar-structured particles exhibit a single-domain behavior, and each columnar-structured particle has an easy magnetization axis in a longitudinal direction thereof and a plurality of the columnar-structured particles are arranged substantially parallel to one another in a diameter direction via the insulating matrix to form a repetitive structure, the columnar-structured particles are made of metal having a composition of Ni x Fe (100-x) alloy (75≦x≦85 at %), an iron, or a composition of Fe y Co (100-y) alloy (50≦y≦70 at %).