JP2006049706A - Switched connection type soft-magnetic material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a soft-magnetic material having a high saturated magnetic-flux density, an excellent soft-magnetic characteristic, and a wide film-thickness range, wherein its magnetic anisotropy is controlled by a switched connection. <P>SOLUTION: In the soft-magnetic material, there are included a composite bedding film which comprises an Mn-based alloy bedding film represented by the formula of Mn<SB>a</SB>M<SB>1-a</SB>/M' and a metal bedding film, and a film represented by the formula of (Fe<SB>x</SB>Co<SB>1-x</SB>)<SB>y</SB>(A)<SB>1-y</SB>. In the formula of Mn<SB>a</SB>M<SB>1-a</SB>/M', the symbol (a) satisfies the relation of 0.4≤a≤0.95, and M is at least one kind selected from the group comprising Fe, Ir, Pt, Cr, Rh, Ru, Pd, Ni, Co, Au, Cu and Ag, and further, M' is at least one kind selected from the group comprising Ag, Al, Au, Co, Cr, Cu, Fe, Ir, Mo, Nb, Ni, Pd, Pt, Rh, Ru, Ta, Ti, V, W and Zr. In the formula of (Fe<SB>x</SB>Co<SB>1-x</SB>)<SB>y</SB>(A)<SB>1-y</SB>, the symbol (x) satisfies the relation of 0.6≤x≤0.8, (y) satisfies the relation of 0<1-y≤0.05, and further, A is at least one kind selected from the group comprising the oxides and nitrides of Mg, Al, Si, Ti, V, Cr and Mn. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a soft magnetic material in which magnetic anisotropy is controlled by exchange coupling, and in particular, an exchange that can be suitably used as a core material of a magnetic head capable of dealing with a soft magnetic backing film of a perpendicular magnetic recording medium and a high coercivity recording medium The present invention relates to a soft magnetic material whose magnetic anisotropy is controlled by bonding.

  With the increase in capacity and speed of information recording, there has been remarkable progress in information storage devices in recent years. In particular, hard disks with large capacity, high speed, excellent reliability, and capable of rewriting information have built a solid position among information storage devices.

  As the recording density increases due to the increase in capacity, the recording system is changing from in-plane magnetic recording to perpendicular magnetic recording. A perpendicular magnetic recording medium requires a backing film made of a soft magnetic film, and the control of the magnetic anisotropy is a problem. Further, since the soft magnetic backing film is relatively thick, it is necessary to reduce the film thickness from the viewpoint of productivity, and a soft magnetic film having a high saturation magnetic flux density is required.

  On the other hand, the coercive force of magnetic recording media tends to increase. As a core material of a magnetic head for recording on such a high coercive force recording medium, a soft magnetic film having a higher saturation magnetic flux density is required, and control of magnetic anisotropy is an issue.

  In addition, in order to reduce the eddy current loss in the high frequency region, a soft magnetic film having a high electrical resistivity is required for both the soft magnetic backing film and the magnetic head core material.

As described above, a high saturation magnetic flux density can be cited as a characteristic required for a soft magnetic underlayer for a perpendicular magnetic recording medium or a soft magnetic film used for a magnetic head core material. Fe _x Co _1-y alloy (0.6 ≦ x ≦ 0.8) is known to have a high saturation magnetic flux density of 2.4 T or more, and has been studied for many years. However, when a FeCo alloy having this composition is formed into a thin film by a normal sputtering method, the coercive force is 50 to 100 Oe, and cannot be used as a soft magnetic backing film for a perpendicular magnetic recording medium or a magnetic head core material. Recently, however, it has been reported that the coercivity in the hard axis direction of an FeCo-based alloy can be reduced by laminating an FeCo-based alloy film on a soft magnetic underlayer (see Non-Patent Document 1). . As a result, a high saturation magnetic flux density, excellent soft magnetic properties, and a wide film thickness range can be achieved simultaneously using an FeCo-based alloy having a high saturation magnetic flux density of 2.3 T or more. Further, since the soft magnetic material having such a laminated structure has a large design margin and manufacturing margin, it can be applied not only to the soft magnetic backing film material and the magnetic head core material but also to a thin film inductor, a thin film transformer, a high frequency noise filter, and the like. However, conventional techniques cannot control the magnetic anisotropy of FeCo alloys well.

Another characteristic required for a soft magnetic film for use in a soft magnetic backing film for a perpendicular magnetic recording medium or a magnetic head core material is high electrical resistivity. The Fe _x Co _1-x alloy (0.6 ≦ x ≦ 0.8) has a high saturation magnetic flux density of 2.4 T or more, but its electrical resistivity is about 10 μΩ · cm. The electrical resistivity can be increased by adding an insulator to the Fe _x Co _1-x alloy having the above composition, but the magnetic anisotropy cannot be controlled well while maintaining good soft magnetic properties. .

Therefore, on the other hand, it is necessary to find a soft magnetic material that can satisfactorily control the magnetic anisotropy without impairing the excellent features of high saturation magnetic flux density, excellent soft magnetic properties, and a wide film thickness range. On the other hand, it is necessary to find a soft magnetic material having a high electric resistivity and a good control of magnetic anisotropy without impairing the excellent soft magnetic properties and the excellent feature of a wide film thickness range. Become.
K. Shintaku, K. Yamakawa, and K. Ouchi, "High-Bs Fe-Co-Al-O soft magnetic films," J. Appl. Phys., Vol. 93, no. 10, pp. 6474-6476, 2003.

  An object of the present invention is to provide a soft magnetic material having high saturation magnetic flux density or high electrical resistivity, excellent soft magnetic properties, and a wide film thickness range, and whose magnetic anisotropy is controlled by exchange coupling. There is.

Soft magnetic material anisotropy is controlled by the exchange coupling of the first aspect of the present invention is represented by the following general formula _{Mn a M 1-a / M} '( where, 0.4 ≦ a ≦ 0.95 M is at least one selected from the group consisting of Fe, Ir, Pt, Cr, Rh, Ru, Pd, Ni, Co, Au, Cu and Ag, and M ′ is Ag, Al, Au, (Co, Cr, Cu, Fe, Ir, Mo, Nb, Ni, Pd, Pt, Rh, Ru, Ta, Ti, V, W, and Zr). a composite base film made of Mn-based alloy underlayer and the metal underlayer, the following general formula _{(Fe x Co 1-x)} y (a) 1-y ( where a 0.6 ≦ x ≦ 0.8, 0 <1-y ≦ 0.05, and A is a group consisting of oxides and nitrides of Mg, Al, Si, Ti, V, Cr and Mn Characterized in that it comprises a membrane which is represented by at least one a is) selected.

Soft magnetic material anisotropy is controlled by the exchange coupling in accordance with a second aspect of the present invention is represented by the following general formula _{Mn a M 1-a / M} '( where, 0.4 ≦ a ≦ 0.95 M is at least one selected from the group consisting of Fe, Ir, Pt, Cr, Rh, Ru, Pd, Ni, Co, Au, Cu and Ag, and M ′ is Ag, Al, Au, (Co, Cr, Cu, Fe, Ir, Mo, Nb, Ni, Pd, Pt, Rh, Ru, Ta, Ti, V, W, and Zr). a composite base film made of Mn-based alloy underlayer and the metal underlayer, the following general formula _{(Fe x Co 1-x)} y (a) 1-y ( where a 0.6 ≦ x ≦ 0.8, 0.05 ≦ 1-y ≦ 0.3, and A is composed of oxides and nitrides of Mg, Al, Si, Ti, V, Cr, and Mn. Characterized in that it comprises a membrane which is represented by at least one a is) to be more selective.

In the soft magnetic material according to the present invention, the thickness of the Mn-based alloy underlayer is 5nm or more, the thickness of the metal base layer is 3nm or _{more, (Fe x Co 1-x} ) y (A) 1-y film with The thickness is preferably 20 to 1000 nm.

  The soft magnetic material according to the first aspect of the present invention has a high saturation magnetic flux density, excellent soft magnetic properties, and magnetic anisotropy is controlled by exchange coupling. When this soft magnetic material is used as a soft magnetic backing film for a perpendicular magnetic recording medium, noise caused by the backing film can be reduced, so that reproduced signal quality is improved. When this soft magnetic material is used as a magnetic head core material, information can be easily written on a recording medium having a high coercive force, and a stable magnetic domain can be formed on the recording medium, so that the reproduction signal quality is improved.

  The soft magnetic material according to the second aspect of the present invention has high electrical resistivity, excellent soft magnetic properties, and magnetic anisotropy is controlled by exchange coupling. When this soft magnetic material is used as a soft magnetic backing film for a perpendicular magnetic recording medium or a magnetic head core material, the eddy current loss in the high frequency region can be reduced, and the reproduction signal quality is improved.

  In addition, since the soft magnetic material according to the present invention can obtain desired magnetic characteristics in a wide range of film thickness, the design margin and manufacturing margin of the perpendicular magnetic recording medium and the magnetic head can be increased.

  Hereinafter, the soft magnetic material whose magnetic anisotropy is controlled by exchange coupling according to the present invention will be described in detail.

  The high saturation magnetic flux density soft magnetic material in which magnetic anisotropy is controlled by exchange coupling according to the present invention has a composite base film composed of a Mn-based alloy base film and a metal base film.

  As the Mn-based alloy base film, MnFe alloy, MnIr alloy, MnPt alloy, MnCr alloy, MnRh alloy, MnRu alloy, MnPd alloy, MnNi alloy, MnCo alloy, MnAu alloy, MnCu alloy, MnAg alloy, MnRhRu alloy, MnFeRh alloy, A MnPtPd alloy, a MnPtCr alloy, a MnNiCr alloy, etc. are mentioned.

  As the metal base film, Ag, Al, Au, Co, Cr, Cu, Fe, Mn, Ir, Mo, Nb, Ni, Pd, Pt, Rh, Ru, Ta, Ti, V, W, Zr, AgCu alloy , AuCu alloy, AuNi alloy, AuPd alloy, CoFe alloy, CoMn alloy, CoNi alloy, CoPd alloy, CrFe alloy, CrMo alloy, CrNi alloy, CrV alloy, CrW alloy, CuMn alloy, CuNi alloy, CuPd alloy, CuV alloy, FeMn Alloy, FeNi alloy, FePd alloy, MnNi alloy, MoNb alloy, MoTa alloy, MoTi alloy, MoV alloy, MoW alloy, MoZr alloy, NbTa alloy, NbTi alloy, NbV alloy, NbW alloy, NbZr alloy, NiPd alloy, TaTi alloy, TaV alloy, TaW alloy, TiV alloy, TiZr alloy etc. .

As the Mn-based alloy base film, a film showing a function of reducing the coercive force of the FeCo-based alloy soft magnetic film when used as the base film of the FeCo-based alloy soft magnetic film is used. Generally the Mn-based alloy underlayer formula Mn _a M _1-a (M is at least one kind of Fe, Ir, Pt, Cr, Rh, Ru, Pd, Ni, Co, Au, is selected from the group consisting of Cu and Ag The Mn composition a needs to satisfy 0.4 ≦ a ≦ 0.95. It is preferable that 0.5 ≦ a ≦ 0.95 for an Mn-based alloy containing Ir, Rh, or Ru, and 0.4 ≦ a ≦ 0.85 for an Mn-based alloy containing other elements.

  As the metal base film provided below the Mn-based alloy base film, a film having a function of improving the crystallinity and orientation of the Mn-based alloy base film is used. The material for the metal underlayer can be selected from a very wide range. By providing the metal base film, strong exchange coupling is generated between the Mn-based alloy base film and the FeCo-based alloy soft magnetic film.

The FeCo-based alloy soft magnetic film contains Fe _x Co _1-x (0.6 ≦ x ≦ 0.8) as a main component. It is known that FeCo having an appropriate composition reaches a maximum value of 2.45 T, which is the maximum value that can be obtained in an alloy system, by adjusting a sputtering target and film formation conditions. An FeCo alloy having a composition range represented by Fe _x Co _1-x (0.6 ≦ x ≦ 0.8) has a saturation magnetic flux density close to the above value. In the present invention, 30% or less A (where A is Mg, Al, Si, Ti, V, Cr and Mn) with respect to Fe _x Co _1-x (0.6 ≦ x ≦ 0.8). A soft magnetic film having a composition containing at least one selected from the group consisting of oxides and nitrides is used.

  In the soft magnetic material according to the first aspect of the present invention, in order to obtain a high saturation magnetic flux density of 2.3 T or more, the A content is preferably 0.5 to 5%. If the A content is less than 0.5%, the coercive force in the hard axis direction tends to increase. When the A content exceeds 5%, the saturation magnetic flux density tends to decrease.

  In the soft magnetic material according to the second aspect of the present invention, in order to obtain a high electrical resistivity of 100 μΩ · cm or more, the A content is preferably 5 to 30%. If the A content is less than 5%, the electrical resistivity tends to be low. If the A content exceeds 30%, the soft magnetic properties tend to deteriorate.

Soft magnetic material according to the present invention, by forming the Mn-based alloy underlayer and a metal base on the composite base film formed with a film _{(Fe x Co 1-x)} y (A) 1-y film, The magnetic anisotropy is controlled by exchange coupling while exhibiting high saturation magnetic flux density or high electrical resistivity and good soft magnetic properties.

  The soft magnetic material according to the first aspect of the present invention has a high saturation magnetic flux density, excellent soft magnetic properties, and magnetic anisotropy is controlled by exchange coupling. When this soft magnetic material is used as a soft magnetic backing film for a perpendicular magnetic recording medium, noise caused by the backing film can be reduced, so that reproduced signal quality is improved. When this soft magnetic material is used as a magnetic head core material, information can be easily written on a recording medium having a high coercive force, and a stable magnetic domain can be formed on the recording medium, so that the reproduction signal quality is improved.

  The soft magnetic material according to the second aspect of the present invention has high electrical resistivity, excellent soft magnetic properties, and magnetic anisotropy is controlled by exchange coupling. When this soft magnetic material is used as a soft magnetic backing film for a perpendicular magnetic recording medium or a magnetic head core material, the eddy current loss in the high frequency region can be reduced, and the reproduction signal quality is improved.

The soft magnetic material anisotropy is controlled by the exchange coupling in accordance with the present invention, the thickness of the Mn-based alloy underlayer is 5nm or more, the thickness of the metal base layer is 3nm or more, (Fe _x Co _1-x ) The film thickness of the _y (A) _1-y film is preferably 20 to 1000 nm. When the film thickness is within this range, excellent soft magnetic characteristics can be obtained, and a large anisotropic magnetic field controlled by exchange coupling can be obtained. Since desired magnetic characteristics can be obtained in such a wide range of film thickness, the design margin and manufacturing margin of the perpendicular magnetic recording medium or magnetic head can be increased.

In the present _{invention, (Fe x Co 1-x} ) y (A) 1-y film can be deposited by a sputtering method. Specifically, the following method can be used.

  1) Sputtering is performed using a sintering target containing 5% or less of A in FeCo.

  2) Simultaneous sputtering is performed using an FeCo alloy target and an A target.

  3) Sputtering is performed using a composite target with an A chip attached on an FeCo alloy target.

  Once the sputtering conditions are determined, a soft magnetic material having desired magnetic properties can be stably produced thereafter. The Mn alloy base film and the metal base film can also be formed by the same method.

  In the following examples, a soft magnetic material having the configuration shown in FIG. 1 was produced. As shown in FIG. 1, a metal base film 2, a Mn alloy base film 3, and an FeCo soft magnetic film 4 are formed on a substrate 1.

Example 1
As a target, a disc-shaped sintered body having a diameter of 100 mm and a thickness of 3 mm, Pt, Mn _0.8 Ir _0.2 and (Fe _0.70 Co _0.30 ) _0.99 (Al ₂ O ₃ ) _0.01 was used. A substrate in which silicon oxide was formed on the surface of a 10 mm square and 1 mm thick silicon was used.

  The above three targets and the substrate were fixed in a vacuum tank of a six-target high-frequency magnetron sputtering apparatus (SPM-505 manufactured by Tokki), and the distance between the substrate and the target was adjusted to about 75 mm. In order to impart magnetic anisotropy to the soft magnetic film, a permanent magnet is disposed outside the substrate so that a magnetic field of 100 Oe or more is applied at the center of the substrate.

The inside of the vacuum chamber was evacuated to 2 × 10 ⁻⁵ Pa. Thereafter, Ar gas was introduced into the vacuum chamber, and the gas flow rate was adjusted so that the pressure was 1 Pa. High frequency sputtering was performed at a discharge power of 400 W and a discharge frequency of 13.56 MHz. 10nm The metal base layer by using a Pt alloy target on a substrate, Mn _0.8 Ir _0.2 10nm a Mn-based alloy underlayer film using an alloy target used _{(Fe 0.70 Co 0.30) 0.99 (} Al 2 O 3) 0.01 alloy target An FeCo-based soft magnetic film was deposited to 100 nm.

As a comparative example, only an Fe ₇₀ Co ₃₀ alloy target containing no Al ₂ O ₃ was prepared, and only an Fe ₇₀ Co ₃₀ film having a thickness of about 100 nm was deposited on the substrate in the same procedure as described above.

For reference, a (Fe _0.70 Co _0.30 ) _0.99 (Al ₂ O ₃ ) _0.01 film having a thickness of about 100 nm was deposited on the substrate in the same procedure as above without forming the MnIr / Pt underlayer.

  The characteristics of the FeCo-based soft magnetic film produced as described above were evaluated. A vibrating sample magnetometer (VSM) was used for the measurement.

FIG. 2 shows the magnetization curve of the soft magnetic material of this example having a MnIr / Pt underlayer and (Fe _0.70 Co _0.30 ) _0.99 (Al ₂ O ₃ ) _0.01 . The saturation magnetic flux density was 2.42 T, the coercivity in the hard axis direction was 0.3 Oe, and the anisotropic magnetic field was 50 Oe, indicating a high saturation magnetic flux density, good soft magnetic properties, and magnetic anisotropy. It can also be seen from the magnetization curve in the easy axis direction that a bias magnetic field is generated by exchange coupling and the magnetic domain is controlled.

FIG. 3 shows a typical magnetization curve of only the Fe ₇₀ Co ₃₀ film. The saturation magnetic flux density was 2.45 T, and the coercive force in the hard axis direction was 100 Oe.

FIG. 4 shows the magnetization curve of only the (Fe _0.70 Co _0.30 ) _0.99 (Al ₂ O ₃ ) _0.01 film. The saturation magnetic flux density was 2.42 T, the coercive force in the hard axis direction was 3 Oe, and the anisotropic magnetic field was 20 Oe.

  2 to 4, it can be seen that the soft magnetic material of this example can significantly improve the soft magnetic characteristics and magnetic anisotropy of the FeCo-based film by providing the MnPt / Pt underlayer.

Example 2
In the same procedure as in Example 1, the Pt film was deposited on the substrate with a fixed film thickness of 10 nm, and the MnIr film was fixed on the film with a fixed film thickness of 10 nm, on which (Fe _0.70 Co _0.30 ) _0.99 (Al ₂ O ₃ ) _0.01 films were deposited in various thicknesses.

FIG. 5 shows the relationship between the coercive force and anisotropic magnetic field in the hard axis direction and the film thickness of the (Fe _0.70 Co _0.30 ) _0.99 (Al ₂ O ₃ ) _0.01 film for the obtained soft magnetic material. From FIG. 5, when the film thickness of the (Fe _0.70 Co _0.30 ) _0.99 (Al ₂ O ₃ ) _0.01 film is 20 to 1000 nm, the coercive force in the hard axis direction is 1 Oe or less and the anisotropic magnetic field is 20 Oe or more. It can be seen that it is.

Further, in all soft magnetic materials in which the film thickness of the (Fe _0.70 Co _0.30 ) _0.99 (Al ₂ O ₃ ) _0.01 film was in the range shown in FIG. 5, the saturation magnetic flux density was substantially constant at 2.42 T.

Example 3
In the same procedure as in Example 1, the Pt film is deposited on the substrate with various thicknesses, and the MnIr film is deposited with the film thickness fixed at 10 nm thereon, and (Fe _0.70 Co _0.30 ) _0.99 thereon. A (Al ₂ O ₃ ) _0.01 film was deposited with a film thickness fixed at about 100 nm.

  FIG. 6 shows the relationship between the coercive force and anisotropic magnetic field in the hard axis direction and the film thickness of the Pt underlayer for the obtained soft magnetic material. From FIG. 6, it can be seen that if the thickness of the Pt film is 3 nm or more, the coercive force in the hard axis direction is 1 Oe or less and the anisotropic magnetic field is 50 Oe or more.

  Further, in all soft magnetic materials having a Pt film thickness in the range shown in FIG. 6, the saturation magnetic flux density was substantially constant at 2.42T.

Example 4
In the same procedure as in Example 1, a Pt film was deposited on a substrate with a fixed thickness of 10 nm, and a MnIr film was deposited thereon with various film thicknesses, and (Fe _0.70 Co _0.30 ) _0.99 ( An Al ₂ O ₃ ) _0.01 film was deposited with a fixed film thickness of about 100 nm.

  FIG. 7 shows the relationship between the coercive force and anisotropic magnetic field in the hard axis direction and the film thickness of the MnIr film for the obtained soft magnetic material. From FIG. 7, it can be seen that if the thickness of the MnIr film is 5 nm or more, the coercive force in the hard axis direction is 1 Oe or less and the anisotropic magnetic field is 50 Oe or more.

  Further, in all soft magnetic materials in which the film thickness of the MnIr film is in the range shown in FIG. 7, the saturation magnetic flux density was substantially constant at 2.42T.

Example 5
As targets for FeCo-based soft magnetic films, sintered bodies having different contents of Al ₂ O ₃ (Fe _0.70 Co _0.30 ) _y (Al ₂ O ₃ ) _1-y (0.005 ≦ 1-y ≦ 0.05) A FeCo-based soft magnetic film containing Al ₂ O ₃ with various contents was deposited on the substrate through a MnIr / Pt underlayer in the same procedure as in Example 1 except that was used.

FIG. 8 shows the relationship between the saturation magnetic flux density and the coercivity in the hard axis direction and the Al ₂ O ₃ content of the obtained soft magnetic material. FIG. 8 shows that when the Al ₂ O ₃ content is 0.5 to 5%, the saturation magnetic flux density is 2.3 T or more and the coercive force in the hard axis direction is 1 Oe or less.

Further, in all the soft magnetic materials in which the composition of the (Fe _0.70 Co _0.30 ) _y (Al ₂ O ₃ ) _{1 -y} film is in the range shown in FIG. 8, the anisotropic magnetic field was 50 Oe or more.

Example 6
Ag, Al, Au, Co, Cr, Cu, Fe, Mn, Ir, Mo, Nb, Ni, Pd, Pt, Rh, Ru, Ta, Ti, V, W, as a target for the metal underlayer (M ′) Using a simple metal or alloy selected from the group consisting of Zr and depositing a metal base film on the substrate and depositing a MnIr film on the substrate in the same procedure as in Example 1, (Fe _0.70 Co _0.30 ) _0.99 (Al ₂ O ₃ ) _0.01 film was deposited _thereon .

  Table 1 shows values of saturation magnetic flux density (Bs), hard axis coercive force (Hch), and anisotropic magnetic field (Hk) for some of the obtained soft magnetic materials.

  Table 1 shows that for all soft magnetic materials, the saturation magnetic flux density is 2.3 T or more, the coercivity in the hard axis direction is 1 Oe or less, and the anisotropic magnetic field is 30 Oe or more.

Example 7
Mn _a M _1-a (0.4 ≦ a ≦ 0) in which the alloy component M is Fe, Ir, Pt, Cr, Rh, Ru, Pd, Ni, Co, Au, Cu, or Ag as the Mn-based alloy underlayer target .95), and a Pt underlayer film is deposited on the substrate and a Mn-based alloy underlayer film is deposited thereon, and (Fe _0.70 Co _0.30 ) _0.99 (Al ₂ An O ₃ ) _0.01 film was deposited.

  Table 2 shows values of saturation magnetic flux density (Bs), hard axis coercive force (Hch), and anisotropic magnetic field (Hk) for the obtained soft magnetic material.

  Table 2 shows that for all soft magnetic materials, the saturation magnetic flux density is 2.3 T or more, the coercivity in the hard axis direction is 1 Oe or less, and the anisotropic magnetic field is 20 Oe or more.

Example 8
A Pt underlayer was formed on the substrate in the same procedure as in Example 1 except that a sintered body having a different A (Fe _0.70 Co _0.30 ) _0.99 (A) _0.01 was used as the target of the FeCo-based soft magnetic film. Then, a Mn alloy base film was deposited thereon, and a FeCo soft magnetic film was deposited thereon.

  Table 3 shows the values of saturation magnetic flux density (Bs), hard axis coercive force (Hch), and anisotropic magnetic field (Hk) for some of the obtained soft magnetic materials.

  Table 3 shows that for all soft magnetic materials, the saturation magnetic flux density is 2.3 T or more, the coercivity in the hard axis direction is 1 Oe or less, and the anisotropic magnetic field is 40 Oe or more. If the A content is in the range of 0.5% or more and 5% or less, the saturation magnetic flux density is 2.3 T or more, the coercive force in the hard axis direction is 1 Oe or less, and anisotropy. The magnetic field was 30 Oe or more.

Example 9
Except for using a sintered body of (Fe _0.70 Co _0.30 ) _y (Al ₂ O ₃ ) _1-y (0.005 ≦ 1-y ≦ 0.3) having different Al ₂ O ₃ content as a target. In the same procedure as in Example 1, FeCo-based soft magnetic films containing Al ₂ O ₃ with various contents were deposited on a substrate via a MnIr / Pt underlayer.

FIG. 9 shows the relationship between the electrical resistivity, the coercive force in the hard axis direction, and the Al ₂ O ₃ content of the obtained soft magnetic material. FIG. 9 shows that when the Al ₂ O ₃ content is 5 to 30%, the electrical resistivity is 100 μΩ · cm or more and the coercive force in the hard axis direction is 2 Oe or less.

Further, in all soft magnetic materials in which the composition of the (Fe _0.70 Co _0.30 ) _y (Al ₂ O ₃ ) _{1 -y} film is in the range shown in FIG. 9, the anisotropic magnetic field was 30 Oe or more.

Sectional drawing of the soft-magnetic material produced in the Example of this invention. Shows the magnetization curve of the soft magnetic material containing MnIr / Pt underlayer and _{(Fe 0.70 Co 0.30) 0.99 (} Al 2 O 3) 0.01 film in Example 1. Shows the magnetization curves of Fe ₇₀ Co ₃₀ film only. _{(Fe 0.70 Co 0.30) 0.99 (} Al 2 O 3) shows the magnetization curve of only _0.01 membrane. The soft magnetic material according to Example 2, showing the relationship between the thickness of the hard axis direction of the coercive force and the anisotropic magnetic field _{(Fe 0.70 Co 0.30) 0.99 (} Al 2 O 3) 0.01 film FIG. The figure which shows the relationship between the coercive force and anisotropic magnetic field of a hard-axis direction, and the film thickness of Pt film | membrane about the soft magnetic material in Example 3. The figure which shows the relationship between the coercive force and anisotropic magnetic field of a hard-axis direction, and the film thickness of a MnIr film | membrane about the soft-magnetic material in Example 4. FIG. The soft magnetic material according to Example 5, illustrates the relationship between the Al ₂ O ₃ content in the saturated magnetic flux density and the hard axis coercivity and FeCo-based soft magnetic film. The soft magnetic material according to Example 9, shows the relationship between the content of Al ₂ O ₃ of the electric resistivity and the hard axis coercivity and FeCo-based soft magnetic film.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Board | substrate, 2 ... Metal base film, 3 ... Mn type alloy base film, 4 ... FeCo type soft magnetic film.

Claims (3)

The following general formula _{Mn a M 1-a / M} '
(Where 0.4 ≦ a ≦ 0.95, and M is at least one selected from the group consisting of Fe, Ir, Pt, Cr, Rh, Ru, Pd, Ni, Co, Au, Cu, and Ag. M ′ is a seed from the group consisting of Ag, Al, Au, Co, Cr, Cu, Fe, Ir, Mo, Nb, Ni, Pd, Pt, Rh, Ru, Ta, Ti, V, W, and Zr. At least one selected)
A composite base film made of Mn-based alloy underlayer and the metal underlying film represented in the following general formula _{(Fe x Co 1-x)} y (A) 1-y
(Where 0.6 ≦ x ≦ 0.8, 0 <1-y ≦ 0.05, and A is an oxide and nitride of Mg, Al, Si, Ti, V, Cr and Mn. At least one selected from the group consisting of:
And a soft magnetic material whose magnetic anisotropy is controlled by exchange coupling. The following general formula _{Mn a M 1-a / M} '
(Where 0.4 ≦ a ≦ 0.95, and M is at least one selected from the group consisting of Fe, Ir, Pt, Cr, Rh, Ru, Pd, Ni, Co, Au, Cu, and Ag. M ′ is a seed from the group consisting of Ag, Al, Au, Co, Cr, Cu, Fe, Ir, Mo, Nb, Ni, Pd, Pt, Rh, Ru, Ta, Ti, V, W, and Zr. At least one selected)
A composite base film made of Mn-based alloy underlayer and the metal underlying film represented in the following general formula _{(Fe x Co 1-x)} y (A) 1-y
(Where 0.6 ≦ x ≦ 0.8, 0.05 ≦ 1-y ≦ 0.3, A is an oxide and nitridation of Mg, Al, Si, Ti, V, Cr and Mn At least one selected from the group consisting of products)
And a soft magnetic material whose magnetic anisotropy is controlled by exchange coupling. Thickness of the Mn-based alloy underlayer is 5nm or more, the thickness of the metal base layer is 3nm or more, the _{(Fe x Co 1-x)} y (A) the thickness of the _1-y layer is a 20~1000nm The soft magnetic material having magnetic anisotropy controlled by exchange coupling according to claim 1 or 2.

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