US5068147A
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Soft magnetic thin film comprising alternate layers of iron carbide with either iron, iron nitride or iron carbon-nitride
Assignee: Panasonic Holdings Corp
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Filing: 1989-04-27
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Granted: 1991-11-26
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Expires: 2009-04-27
Abstract
Abstract In a soft-magnetic thin film, layers of iron carbide are laminated alternately with layers of at least one of iron, iron nitride and iron carbon-nitride and when needed, layers of non-magnetic material. The thin film provides particular features including 1) saturation magnetic flux density of at least 1.5 teslas; 2) relative permeability and coercive force greater than those of the conventional soft-magnetic material; and 3) durability for practical use.
Inventors
- 👤 Tohru Hori
- 👤 Masaki Aoki
- 👤 Kenichi Fujii
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:54
CPC Classifications
B; B82; B82Y; B82Y25/00; G; G11; G11B; G11B5/00; G11B5/127; G11B5/31; G11B5/3109; H; H01; H01F; H01F10/00; H01F10/32; H01F10/324; H01F41/00; H01F41/14; H01F41/18; H01F41/183; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
27 words
A soft-magnetic thin film comprising layers of iron carbide and layers of at least one of iron, iron nitride and iron carbon-nitride, which layers are alternately laminated.
Claim 2
Dependent Claim
27 words
A soft-magnetic thin film comprising layers of iron carbide and layers of at least one of iron, iron nitride and iron carbon-nitride, which layers are alternately laminated.
Claim 3
Dependent Claim
36 words
A magnetic head comprising magnetic permeable layers incorporated at least partially with the soft-magnetic thin film defined in claim 1, a magnetic gap, and coils for control of a magnetic flux across the magnetic permeable layers.
Claim 4
Dependent Claim
50 words
A soft-magnetic thin film in which iron layers and iron carbide layers containing carbon at a density providing a positive magnetostriction constant are alternately laminated, wherein the thickness of each iron layer is 0.5 to 60 nm and the thickness of each iron carbide layer is 3 to 800 nm.
Claim 5
Dependent Claim
50 words
A soft-magnetic thin film in which iron layers and iron carbide layers containing carbon at a density providing a positive magnetostriction constant are alternately laminated, wherein the thickness of each iron layer is 0.5 to 60 nm and the thickness of each iron carbide layer is 3 to 800 nm.
Claim 6
Dependent Claim
57 words
A soft-magnetic thin film in which iron carbide layers containing 4 to 35% of carbon in mole percentage and iron nitride layers composed mainly of γFe 4 N are alternately laminated, wherein the thickness of each iron carbide layer is 3 to 1000 nm and the thickness of each iron nitride layer is 0.6 to 200 nm.
Claim 7
Dependent Claim
57 words
A soft-magnetic thin film in which iron carbide layers containing 4 to 35% of carbon in mole percentage and iron nitride layers composed mainly of γFe 4 N are alternately laminated, wherein the thickness of each iron carbide layer is 3 to 1000 nm and the thickness of each iron nitride layer is 0.6 to 200 nm.
Claim 8
Dependent Claim
57 words
A soft-magnetic thin film in which iron carbide layers containing 8 to 25% of carbon in mole percentage and iron nitride layers composed mainly of γFe 4 N are alternately laminated, wherein the thickness of each iron carbide layer is 10 to 150 nm and the thickness of each iron nitride layer is 1 to 10 nm.
Claim 9
Dependent Claim
57 words
A soft-magnetic thin film in which iron carbide layers containing 8 to 25% of carbon in mole percentage and iron nitride layers composed mainly of γFe 4 N are alternately laminated, wherein the thickness of each iron carbide layer is 10 to 150 nm and the thickness of each iron nitride layer is 1 to 10 nm.
Claim 10
Dependent Claim
60 words
A soft-magnetic thin film in which iron carbide layers containing 3 to 35% of carbon in mole percentage and iron carbon-nitride layers containing 0.2 to 15% of nitrogen in mole percentage are alternately laminated, wherein the thickness of each iron carbide layer is 0.5 to 1000 nm and the thickness of each iron carbon-nitride layer is 0.5 to 300 nm.
Claim 11
Dependent Claim
60 words
A soft-magnetic thin film in which iron carbide layers containing 3 to 35% of carbon in mole percentage and iron carbon-nitride layers containing 0.2 to 15% of nitrogen in mole percentage are alternately laminated, wherein the thickness of each iron carbide layer is 0.5 to 1000 nm and the thickness of each iron carbon-nitride layer is 0.5 to 300 nm.
Claim 12
Dependent Claim
60 words
A soft-magnetic thin film in which iron carbide layers containing 5 to 30% of carbon in mole percentage and iron carbon-nitride layers containing 5 t 10% of nitrogen in mole percentage are alternately laminated, wherein the thickness of each iron carbide layer is 5 to 100 nm and the thickness of each iron carbon-nitride layer is 5 to 90 nm.
Claim 13
Dependent Claim
60 words
A soft-magnetic thin film in which iron carbide layers containing 5 to 30% of carbon in mole percentage and iron carbon-nitride layers containing 5 t 10% of nitrogen in mole percentage are alternately laminated, wherein the thickness of each iron carbide layer is 5 to 100 nm and the thickness of each iron carbon-nitride layer is 5 to 90 nm.
Claim 14
Dependent Claim
46 words
A soft-magnetic thin film in which layers of iron carbide and layers of at least one of iron, iron nitride and iron carbon-nitride are alternately laminated, and a non-magnetic material layer is interposed between at least one pair of adjacent layers of the alternately laminated layers.
Claim 15
Dependent Claim
46 words
A soft-magnetic thin film in which layers of iron carbide and layers of at least one of iron, iron nitride and iron carbon-nitride are alternately laminated, and a non-magnetic material layer is interposed between at least one pair of adjacent layers of the alternately laminated layers.
Claim 16
Dependent Claim
36 words
A magnetic head comprising magnetic permeable layers incorporated at least partially with the soft-magnetic thin film defined in claim 8, a magnetic gap, and coils for control of a magnetic flux across the magnetic permeable layers.
Claim 17
Dependent Claim
45 words
A soft-magnetic thin film in which iron layers and iron carbide layers containing carbon at a density providing a positive magnetostriction constant are alternately laminated, and a non-magnetic material layer is interposed between at least one pair of adjacent layers of the alternately laminated layers.
Claim 18
Dependent Claim
45 words
A soft-magnetic thin film in which iron layers and iron carbide layers containing carbon at a density providing a positive magnetostriction constant are alternately laminated, and a non-magnetic material layer is interposed between at least one pair of adjacent layers of the alternately laminated layers.
Claim 19
Dependent Claim
51 words
A soft-magnetic thin film in which iron carbide layers containing 4% to 35% of carbon in mole percentage and iron nitride layers composed mainly of γFe 4 N are alternately laminated, and a non-magnetic material layer is interposed between at least one pair of adjacent layers of the alternately laminated layers.
Claim 20
Dependent Claim
51 words
A soft-magnetic thin film in which iron carbide layers containing 4% to 35% of carbon in mole percentage and iron nitride layers composed mainly of γFe 4 N are alternately laminated, and a non-magnetic material layer is interposed between at least one pair of adjacent layers of the alternately laminated layers.
Claim 21
Dependent Claim
51 words
A soft-magnetic thin film in which iron carbide layers containing 8 to 25% of carbon in mole percentage and iron nitride layers composed mainly of γFe 4 N are alternately laminated, and a non-magnetic material layer is interposed between at least one pair of adjacent layers of the alternately laminated layers.
Claim 22
Dependent Claim
51 words
A soft-magnetic thin film in which iron carbide layers containing 8 to 25% of carbon in mole percentage and iron nitride layers composed mainly of γFe 4 N are alternately laminated, and a non-magnetic material layer is interposed between at least one pair of adjacent layers of the alternately laminated layers.
Claim 23
Dependent Claim
54 words
A soft-magnetic thin film in which iron carbide layers containing 3 to 35% of carbon in mole percentage and iron carbon-nitride layers containing 0.2 to 15% of nitrogen in mole percentage are alternately laminated, and a non-magnetic material layer is interposed between at least one pair of adjacent layers of the alternately laminated layers.
Claim 24
Dependent Claim
54 words
A soft-magnetic thin film in which iron carbide layers containing 3 to 35% of carbon in mole percentage and iron carbon-nitride layers containing 0.2 to 15% of nitrogen in mole percentage are alternately laminated, and a non-magnetic material layer is interposed between at least one pair of adjacent layers of the alternately laminated layers.
Claim 25
Dependent Claim
54 words
A soft-magnetic thin film in which iron carbide layers containing 5 to 30% of carbon in mole percentage and iron carbon-nitride layers containing 5 to 10% of nitrogen in mole percentage are alternately laminated, and a non-magnetic material layer is interposed between at least one pair of adjacent layers of the alternately laminated layers.
Claim 26
Dependent Claim
54 words
A soft-magnetic thin film in which iron carbide layers containing 5 to 30% of carbon in mole percentage and iron carbon-nitride layers containing 5 to 10% of nitrogen in mole percentage are alternately laminated, and a non-magnetic material layer is interposed between at least one pair of adjacent layers of the alternately laminated layers.
Claim 27
Independent Claim
50 words
A method of making a multi-layer thin film of iron carbide and iron carbon-nitride comprising the steps of forming an iron carbon-nitride layer by supplying a nitrogen gas during sputtering with an iron carbide target, and forming an iron carbide layer without supplying the nitrogen gas, these steps being repeated.
Claim 28
Independent Claim
50 words
A method of making a multi-layer thin film of iron carbide and iron carbon-nitride comprising the steps of forming an iron carbon-nitride layer by supplying a nitrogen gas during sputtering with an iron carbide target, and forming an iron carbide layer without supplying the nitrogen gas, these steps being repeated.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1994-11-25 | 1995-05-27 | 1995-11-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-11-25 | 1999-05-27 | 1999-11-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-11-25 | 2003-05-27 | 2003-11-26 | $7700.00 | Window Closed / Lapsed |