Claims
- 1. A planar inductor, comprising:a planar inductance element comprising a coil having a plurality of windings, the plurality of windings all extending in the same plane; and at least one ferromagnetic layer stacked on said planar inductance element; wherein said at least one ferromagnetic layer comprises a plurality of ferromagnetic sub-layers stacked directly upon one another with no intervening structure between the plurality of sub-layers.
- 2. The planar inductor according to claim 1, wherein a saturation magnetization 4πMS, of said at least one ferromagnetic layer is not less than 10 Kg.
- 3. The planar inductor according to claim 1, wherein the thickness of each of said plurality of sub-layers is between 4 and 100 μm.
- 4. The planar inductor according to claim 1, wherein an effective permeability μ10k at a frequency of 10 kHz of said at least one ferromagnetic layer is not less than 1×104.
- 5. The planar inductor according to claim 1, wherein said at least one ferromagnetic layer consists of an amorphous alloy ribbon whose composition is represented by the following formula:(Fe1-aMa)100-bXb wherein M is at least one of Ti, V, Cr, Mn, Co, Ni, Zr, Nb, Mo, Hf, Ta, W, and Cu, and X is at least one of Si, B, P, C, Ge, and Al, and 0≦a≦0.15, and 12≦b<30.
- 6. The planar inductor according to claim 1, wherein said at least one ferromagnetic layer consists of a hyperfine grain alloy ribbon obtained by thermally treating an Fe-based amorphous alloy ribbon at a temperature that is higher than a crystallization temperature of said Fe-based amorphous alloy ribbon.
- 7. The planar inductor according to claim 1, wherein insulating layers and ferromagnetic layers are stacked on both surfaces of said planar inductance element.
- 8. The planar inductor according to claim 7, wherein said planar inductance element comprises a spiral coil.
- 9. The planar inductor according to claim 7, wherein said planar inductance element has a structure obtained by stacking a plurality of spiral coils with insulating layers interposed therebetween.
- 10. The planar inductor according to claim 1, further comprising:a coating of a mold resin surrounding said planar inductor element and said at least one ferromagnetic layer; and a relaxation layer formed on said ferromagnetic layer, for providing strain relaxation due to contraction of said coating of a mold resin when said coating of a mold resin is hardened.
- 11. The planar inductor according to claim 10, wherein said relaxation layer consists of an organic polymer film, said organic polymer film having a thermal deformation temperature which is higher than a hardening temperature of the mold resin.
- 12. The planar inductor according to claim 11, wherein said organic polymer film consists of polyphenylenesulfide.
- 13. The planar inductor according to claim 11, wherein the thickness of said organic polymer film is less than 20 μm.
- 14. An inductor according to claim 1, wherein said plurality of sub-layers comprises at least three sub-layers.
- 15. A planar inductor, comprising:a laminated structure including a spiral conductor coil means for conducting a current, said spiral conductor coil means is sandwiched between ferromagnetic layers, each ferromagnetic layer comprising a plurality of ferromagnetic ribbons which are sandwiched together, each ferromagnetic ribbon having a thickness of not more than 100 microns.
- 16. A planar inductor comprising:a first ferromagnetic layer; a coil stacked on said first ferromagnetic layer; a second ferromagnetic layer stacked on said coil; wherein the first ferromagnetic layer comprises a plurality of ferromagnetic sub-layers that are stacked upon one another; and wherein there are no coils between the stacked plurality of ferromagnetic sub-layers.
- 17. A planar inductor, comprising:a first ferromagnetic layer; a coil stacked upon said first ferromagnetic layer; a second ferromagnetic layer stacked upon said coil so that the coil is sandwiched between the first and second ferromagnetic layers; wherein the first ferromagnetic layer comprises a plurality of a sub-layers that are stacked upon one another and the second ferromagnetic layer comprises a plurality of sub-layers that are stacked upon one another; and wherein all coils of the planar inductor are disposed between the first and second ferromagnetic layers.
- 18. A planar inductor, comprising:a planar inductance element; and at least one ferromagnetic layer stacked on said planar inductance element; where said ferromagnetic layer is two-dimensionally divided into a plurality of ferromagnetic portions.
- 19. A planar inductor having an inductance, comprising:at least one ferromagnetic layer, each ferromagnetic layer having a saturation magnetization that is greater than 10 kG and a thickness of less than 100 microns; and a coil stacked on said ferromagnetic layer and having a Plurality of windings, the Plurality of windings all extending in the same plane.
- 20. A planar inductor according to claim 19, wherein said each layer of the plurality of ferromagnetic layers has an effective magnetic permeability of 10,000 at 10 Khz.
- 21. A planar inductor according to claim 19, further comprising:an insulating layer interposed between said coil and said ferromagnetic layer.
- 22. A planar inductor according to claim 19, wherein:said saturization magnetization is greater than 12 kilogauss.
- 23. A planar inductor according to claim 19, further comprising:a plurality of stacked spiral coils; and an insulating layer between each pair of adjacent coils.
- 24. A planar inductor according to claim 19, wherein:said at least one ferromagnetic layer comprises a plurality of ferromagnetic layers.
- 25. An inductor according to claim 19, wherein said at least one ferromagnetic layer comprises at least three ferromagnetic layers.
- 26. A planar inductor, comprising:a laminated structure including a spiral conductor coil means for conducting a current, said spiral conductor coil means comprises a plurality of windings, the plurality of windings all extending in the same plane, wherein said spiral conductor coil means is sandwiched between ferromagnetic layers, each of said ferromagnetic layers comprising a plurality of ferromagnetic ribbons which are sandwiched together; and wherein an effective permeability at 10 kilohertz of each ferromagnetic layer is at least 1×104.
- 27. An inductor according to claim 26, wherein said plurality of ferromagnetic ribbons comprises at least three ferromagnetic ribbons.
- 28. A planar inductor comprising a laminated structure including a planar inductance element comprising a plurality of windings, the plurality of windings all extending in the same plane, said planar inductance element is sandwiched between ferromagnetic layers each including a plurality of ferromagnetic ribbons, each one of said plurality of ferromagnetic ribbons having a thickness of 100 microns or less.
- 29. A planar inductor according to claim 28, further comprising:insulating layers interposed between the planar inductance element and said ferromagnetic layers.
- 30. A planar inductor according to claim 29, wherein the thickness of each ferromagnetic ribbon is in the range between 4 and 100 microns.
- 31. A planar inductor according to claim 29, wherein each ferromagnetic layer has a thickness and a side length, and a ratio of the thickness to the side length of each ferromagnetic layer, composed of a plurality of ferromagnetic ribbons, falls within the range between 2×10−4 and 1×10−2.
- 32. An inductor according to claim 28, wherein said plurality of ferromagnetic ribbons comprises at least three ferromagnetic ribbons.
- 33. A planar inductor, comprising:a planar inductance element comprising a plurality of conducting coils which are stacked upon one another and separated from one another only by an insulating non-ferromagnetic layer, each of said conducting coils comprising a plurality of windings, a first plurality of windings for a first one of the Plurality of conducting coils all extending in the same plane; and at least one ferromagnetic layer stacked on said planar inductance element; wherein said at least one ferromagnetic layer is formed from a plurality of ferromagnetic sub-layers that are stacked upon one another and each of the plurality of ferromagnetic sub-layers has a thickness of 100 microns or less.
- 34. A planar inductor according to claim 33, wherein a saturation magnetization of said at least one ferromagnetic layer is not less than 10 Kg.
- 35. A planar inductor according to claim 33, wherein a thickness of each of said plurality of sub-layers is between 4 and 100 microns.
- 36. A planar inductor according to claim 33, wherein an effective magnetic permeability at a frequency of 10 kHz of said at least one ferromagnetic layer is not less than 1×104.
- 37. An inductor according to claim 33, wherein said plurality of sub-layers comprises at least three sub-layers.
- 38. A planar inductor, comprising:a planar inductance element comprising a plurality of windings, the plurality of windings all extending in the same plane; and at least one ferromagnetic layer stacked on said planar inductance element; wherein said at least one ferromagnetic layer comprises a plurality of ferromagnetic sub-layers which are stacked upon one another and form said ferromagnetic layer and have no electrically conductive material between them.
- 39. An inductor according to claim 38, wherein each of said plurality of ferromagnetic sub-layers is less than 10 microns thick and greater than 7 microns thick.
- 40. An inductor according to claim 38, wherein said plurality of ferromagnetic sub-layers comprises at least three ferromagnetic sub-layers.
- 41. A planar conductor comprising a laminated structure including spiral conductor coil means sandwiched between ferromagnetic layers each including a plurality of ferromagnetic ribbons, each of said ferromagnetic ribbons having a thickness of 100 microns or less.
- 42. An inductor according to claim 41, wherein a saturation magnetization of each of said ferromagnetic layers is not less than 10 kilogauss.
- 43. The inductor according to claim 41, wherein the thickness of each of said plurality of ferromagnetic ribbons is between 4 and 100 microns.
- 44. The inductor according to claim 41, wherein an effective permeability at a frequency of 10 kilohertz of each of said ferromagnetic layers is not less than 1×104.
- 45. An inductor according to claim 41, wherein said spiral conductor coil means comprises a plurality of coils with insulating layers interposed therebetween to form a stack of the plurality of coils and the insulating layers.
Priority Claims (3)
Number |
Date |
Country |
Kind |
63-246432 |
Sep 1988 |
JP |
|
63-246433 |
Sep 1988 |
JP |
|
1-14613 |
Jan 1989 |
JP |
|
Parent Case Info
This application is a continuation of application Ser. No. 07/414,455, filed on Sep. 29, 1989, now abandoned.
US Referenced Citations (8)
Foreign Referenced Citations (3)
Number |
Date |
Country |
3908896 |
Sep 1989 |
DE |
271657 |
Jun 1988 |
EP |
0310396 |
Apr 1989 |
EP |
Non-Patent Literature Citations (1)
Entry |
Technical University Delft, pp. 3.47, Jul. 1983, E. Hommes, et al., “Electrische Machines”. |
Continuations (1)
|
Number |
Date |
Country |
Parent |
07/414455 |
Sep 1989 |
US |
Child |
08/059350 |
|
US |