JP2003197410A - Electromagnetic noise suppressing body and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic noise suppressing body and its manufacturing method, which can provide noise absorption effect in any shape, without being affected by the shape of a conductive pattern. <P>SOLUTION: An electromagnetic noise suppressing body that is a soft magnetic thin film, which has magnetic anisotropy in one direction, and which is composed of M (M is either Fe, Co, or Ni, or mixture of them) -X (X is an element other than M or Y, or mixture of them) -Y (Y is either F, N, or O, or mixture of them. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for various industrial and consumer circuit boards, semiconductor circuit boards, etc.
The present invention relates to an electromagnetic noise suppressor having magnetic anisotropy suitable for taking measures against noise and a method for manufacturing the same.

[0002]

2. Description of the Related Art A conventional electromagnetic noise suppressor will be described. The conventional electromagnetic noise suppressor is an electromagnetic noise suppressor made of a granular magnetic film and having magnetically isotropic properties. FIG. 7: is explanatory drawing of the use condition of the conventional isotropic electromagnetic noise suppression body. FIG. 7A is a diagram showing a case where the isotropic electromagnetic noise suppressor is rectangular, and FIG. 7B is a diagram showing a case where the isotropic electromagnetic noise suppressor is square.

FIG. 7A shows a state in which a rectangular isotropic electromagnetic noise suppressor 21 is formed on a rectangular conductor 31, and FIG. 7B shows a square conductor 41. On top of the,
The state where the square isotropic electromagnetic noise suppressor 22 is formed is shown.

[0004]

Here, the isotropic electromagnetic noise suppressor is a granular magnetic film, and the physical principle of its noise absorption is that the electromagnetic noise between the noise current flowing through the conductor and the granular magnetic film. The noise current is absorbed by the dynamic interaction. However, adding magnetic anisotropy to the magnetic film is effective for noise absorption. Specifically, the direction of current flow of the conductor and the direction of magnetic anisotropy of the magnetic film match. In this case, a remarkable noise absorption effect appears.

FIG. 7 is an explanatory view of noise current absorption in the conventional electromagnetic noise suppressor. In the case of FIG. 7 (a), the isotropic electromagnetic noise suppressor has a rectangular shape, so that the longitudinal direction is reduced. Magnetic anisotropy caused by the shape is generated. Therefore, FIG.
In the case of, remarkable noise current absorption is realized. However, in the case of FIG. 7B, the isotropic electromagnetic noise suppressor is formed on the square conductor, and the isotropic electromagnetic noise suppressor 22 is a square, so that it is magnetically anisotropic. Gender has no direction. Therefore, there is a problem that the degree of noise current absorption with respect to the noise current flowing through the conductor 41 is reduced as compared with the case of FIG. 7A.

As described above, the conventional isotropic electromagnetic noise suppressor has a problem in that its noise current absorption varies depending on its shape.

Therefore, an object of the present invention is to provide an electromagnetic noise suppressor and a method for manufacturing the same that can obtain a noise absorbing effect regardless of the shape of the conductor pattern, regardless of the shape of the conductor pattern. That is.

[0008]

An electromagnetic noise suppressor having magnetic anisotropy according to the present invention is an electromagnetic noise suppressor having magnetic anisotropy in a certain direction, and its material is:
M (M is any one of Fe, Co, Ni, or a mixture thereof) -X (X is an element other than M and Y, or a mixture thereof) -Y (Y is F, N, O) Or a mixture thereof), which is a soft magnetic thin film and is an electromagnetic noise suppressor having magnetic anisotropy.

The electromagnetic noise suppressor having magnetic anisotropy according to the present invention includes a first electromagnetic noise suppressor having magnetic anisotropy in a fixed direction and a magnetic anisotropic body of the first electromagnetic noise suppressor. Second with magnetic anisotropy that makes a certain angle with the direction of sex
The electromagnetic noise suppressor having magnetic anisotropy is formed by laminating the electromagnetic noise suppressor.

The method of manufacturing an electromagnetic noise suppressor having magnetic anisotropy according to the present invention forms a soft magnetic film on a substrate by sputtering using iron and aluminum oxide as targets in an argon atmosphere. And a method for manufacturing an electromagnetic noise suppressor, which is produced by inclining the plane direction of the substrate with respect to the plane direction of the target by a predetermined angle in the direction of giving magnetic anisotropy.

That is, according to the present invention, M (M is Fe, Co,
Any of Ni or their mixture) -X (X
Is an element other than M and Y, or a mixture thereof)
An electromagnetic noise suppressor which is a soft magnetic thin film made of -Y (Y is any of F, N, O, or a mixture thereof) and having magnetic anisotropy in a certain direction.

According to the present invention, the first electromagnetic noise suppressor having magnetic anisotropy in a certain direction, and the magnetic anisotropy direction of the first electromagnetic noise suppressor forming a predetermined angle with the magnetic anisotropy. The electromagnetic noise suppressor is formed by stacking a second electromagnetic noise suppressor having anisotropy.

Further, according to the present invention, the predetermined angle is
The electromagnetic noise suppressor is set to about 90 °.

In the present invention, the material of the electromagnetic noise suppressor is M (M is any one of Fe, Co and Ni, or a mixture thereof) -X (X is an element other than M and Y). , Or a mixture thereof) -Y (Y is F, N, O
Or a mixture thereof) as a soft magnetic thin film.

The present invention is also a method of manufacturing an electromagnetic noise suppressor having magnetic anisotropy in a linear direction, wherein the film-forming step is performed by changing the plane direction of the substrate with respect to the plane direction of the target. This is a method for manufacturing an electromagnetic noise suppressor which is tilted by a predetermined angle in the direction of magnetic anisotropy.

The present invention is also a method for manufacturing a laminated electromagnetic noise suppressor having magnetic anisotropy in a plurality of directions, wherein the manufacturing method comprises two steps of forming a soft magnetic film on a substrate. The first film forming step comprises a step of inclining the plane direction of the substrate by a predetermined angle with respect to the plane direction of the target in a direction in which one direction of magnetic anisotropy is imparted. In the second film forming step, which is a film forming step, the plane direction of the substrate is tilted by a predetermined angle with respect to the plane direction of the target in a direction that imparts magnetic anisotropy in another direction. This is a method for manufacturing an electromagnetic noise suppressor, which is a film forming step.

Further, the present invention is the method of manufacturing an electromagnetic noise suppressor, wherein the film forming step is sputtering using iron and aluminum oxide as targets in an argon atmosphere.

In the present invention, the electromagnetic noise suppressor comprising the soft magnetic thin film is M (M is any one of Fe, Co and Ni or a mixture thereof) -X (X is M and Y). Elements other than, or their mixture) -Y (Y
Is any of F, N, O, or a mixture thereof.
And a method of manufacturing an electromagnetic noise suppressor which is a soft magnetic thin film.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION An electromagnetic noise suppressor having magnetic anisotropy and a method for manufacturing the same according to an embodiment of the present invention will be described below.

(Embodiment 1) An electromagnetic noise suppressor having magnetic anisotropy according to Embodiment 1 of the present invention will be described below. FIG. 1 is an explanatory diagram of a usage state of an electromagnetic noise suppressor having magnetic anisotropy according to a first embodiment of the present invention.
In FIG. 1, 2 is a conductor, and 1 is a uniaxial magnetic anisotropic electromagnetic noise suppressor according to the present invention formed on the conductor 2. The electromagnetic noise suppressor 1 has a uniaxial magnetic anisotropy, its shape is substantially square, and the direction of the magnetic anisotropy (the direction of the arrow in the figure) is the longitudinal direction of the conductor 2. ,
That is, the direction of flow of the current i is matched.

Here, the uniaxial magnetic anisotropic magnetic noise suppressor 1 is a material having a granular magnetic film form,
M (M is any one of Fe, Co, Ni, or a mixture thereof) -X (X is an element other than M and Y, or a mixture thereof) -Y (Y is F, N, O) Or a mixture thereof).

In the case of FIG. 1, the uniaxial magnetic anisotropy magnetic noise suppressor 1 has a square shape, but the magnetic anisotropy is set in the direction of the arrow in the figure. Therefore, the current i flowing through the conductor 2 and the direction of its magnetic anisotropy coincide with each other, and remarkable absorption of noise current is realized.

Here, an example in which the uniaxial magnetic anisotropic electromagnetic noise suppressor 1 absorbs a noise current will be described below. FIG. 2 shows noise absorption characteristics of the uniaxial magnetic anisotropic electromagnetic noise suppressor 1 corresponding to the case of FIG. Figure 2 (a)
Is a diagram showing the reflection amount vs. frequency characteristic of the noise current, FIG.
2 (b) is a diagram showing the transmission attenuation amount of the noise current versus frequency characteristics, FIG. 2 (c) is a diagram showing an evaluation system for measuring the noise absorption characteristics, and FIG. 2 (d) is a magnetic permeability μ ″ versus frequency. It is a figure which shows a characteristic.

In the evaluation system shown in FIG. 2 (c), a microstrip line 31 is formed on an insulating substrate 34 having a copper foil 35 formed on the lower side, and its ends are connected to the core wires of the coaxial cables 32 and 33. , A measurement system connected to the network analyzer 36. Here, the microstrip line 3
1, a uniaxial magnetic anisotropic electromagnetic noise suppressor 1a is arranged. Here, the size of the uniaxial magnetic anisotropic electromagnetic noise suppressor 1a was set to 10 mm × 10 mm.

From the reflection amount vs. frequency characteristic of the noise current shown in FIG. 2A, the reflection amount is -10 decibels or less in the GHz band. On the other hand, it can be seen that the transmission attenuation amount vs. frequency characteristic of the noise current in FIG. 2B shows a transmission attenuation amount of about −5 dB to −18 dB in the GHz band.

As described above, the present soft magnetic thin film realizes the transmission attenuation amount of about −5 dB to −18 dB in the GHz band, and the effect of noise current absorption can be seen.

FIG. 2D shows a comparative example of the magnetic permeability μ "vs. frequency characteristic between the present invention and the conventional isotropic case. Thus, the uniaxial magnetic anisotropic electromagnetic field of the present invention is shown. The noise suppressor has a magnetic permeability μ ″ higher than that of the conventional one, and the peak moves to the higher frequency side. As a result, as shown in FIG. 2B, the transmission attenuation amount is increased more than in the conventional case, and the effect of suppressing electromagnetic noise is exerted.

As described above, since the electromagnetic noise suppressor 1 has the uniaxial magnetic anisotropy in the X direction and the direction of the noise current flowing through the conductor 2 is substantially the same, the electromagnetic noise suppressor 1 is more electromagnetically coupled. Becomes stronger and the noise current can be efficiently absorbed.

(Embodiment 2) FIG. 3 is an explanatory view of a usage state of an electromagnetic noise suppressor having magnetic anisotropy according to Embodiment 2 of the present invention. FIG. 3A is an external view of a single electromagnetic noise suppressor having magnetic anisotropy, and FIG.
FIG. 6 is a diagram showing a state in which an electromagnetic noise suppressor having magnetic anisotropy is formed in a corner portion of the L-shaped conductor 4.

Here, the electromagnetic noise suppressor having magnetic anisotropy is the biaxial magnetic anisotropic electromagnetic noise absorber 3, the structure of which is as shown in FIG. An electromagnetic noise absorber having anisotropy is formed on the first layer, and an electromagnetic noise absorber having magnetic anisotropy in the Y direction of about 90 ° is formed on the first layer.

In this case, as shown in FIG. 3B, the current flowing through the L-shaped conductor 4 is about 90 at the corner.
° You can change the direction. In this case, noise current in each direction and 1 in the biaxial magnetic anisotropic electromagnetic noise absorber 3
The electromagnetic coupling with the anisotropic electromagnetic noise absorber of the second layer or the second layer is strengthened, and the noise current is efficiently absorbed.

(Embodiment 3) FIG. 4 is an explanatory view of a usage state of an electromagnetic noise suppressor having magnetic anisotropy according to Embodiment 3 of the present invention. FIG. 4 shows conductors 5 that are orthogonal to each other.
2 shows a state in which biaxial magnetic anisotropic electromagnetic noise absorbers 6 and 8 having a two-layer structure similar to those of the above-described second embodiment are formed at the intersection of the conductor 7 and the conductor 7.

In this case, the biaxial magnetic anisotropic electromagnetic noise absorbers 6 and 8 are formed in the same process. Also,
An insulator is formed (not shown) at the intersection of the conductor 5 and the conductor 7. Further, the directions of anisotropy of the biaxial magnetic anisotropic electromagnetic noise absorbers 6 and 8 are made to substantially coincide with the longitudinal directions of the conductors 5 and 7.

Here, the noise current flowing in the conductor 5 and the conductor 7 which are orthogonal to each other is the anisotropy of one of the two layers of the biaxial magnetic anisotropic electromagnetic noise absorbers 6 and 8. Therefore, the electromagnetic coupling becomes strong and the noise current is efficiently absorbed with respect to the noise current flowing through either the conductor 5 or the conductor 7, which corresponds to the layer.

(Embodiment 4) FIG. 5 is an explanatory view of a method of manufacturing an electromagnetic noise absorber having uniaxial anisotropy according to Embodiment 4 of the present invention. In FIG. 5, 14 is a chamber of the sputtering apparatus, 11 is a sputtering target, 13 is a substrate holder, 12 is a substrate, and 15 is a plasma region. Here, the substrate holder 13 is inclined by an angle θ with respect to the plane direction of the sputtering target 11.
Therefore, the substrate is also inclined by the angle θ with respect to the plane direction of the sputtering target 11.

Table 1 shows the conditions for the film forming method of the electromagnetic noise suppressor having uniaxial anisotropy.

[0037]

[Table 1]

Under the film forming conditions shown in Table 1, M (M is Fe, C
o, Ni, or their mixture) -X
(X is an element other than M and Y, or a mixture thereof) -Y (Y is any one of F, N, O, or a mixture thereof), and a soft magnetic thin film having a thickness of about several Formed in microns. Here, M is Fe and X is A
One in which O is selected as l and Y is shown as an example. The composition of the soft magnetic thin film is represented by Fe ₇₂ AL ₁₁ O ₁₇ or the like. In addition to Al, Zr, T
Other elements such as i, Si, Ca, Mg, and Ge may be used, but an element having low toxicity is desirable from the environmental aspect.

The uniaxial anisotropy is formed in a direction with an inclination angle θ. Here, it is appropriate to select an angle θ of 5 ° or less.

(Fifth Embodiment) FIG. 6 is an explanatory view of a method of manufacturing an electromagnetic noise absorber having biaxial anisotropy according to a fifth embodiment of the present invention. FIG. 6A is an explanatory diagram of the manufacturing method of the first layer, and FIG. 6B is an explanatory diagram of the manufacturing method of the second layer.

In FIG. 6A, 14 is a chamber of a sputtering apparatus, 11 is a sputtering target, 13 is a substrate holder, 12 'is a substrate, and 15' is a plasma region. Here, the substrate holder 13 is inclined by an angle β with respect to the plane direction of the sputtering target 11. Therefore, the substrate is also inclined by the angle β with respect to the plane direction of the sputtering target 11.

FIG. 6B shows a state in which the substrate holder 13 in the state shown in FIG. 6A has been rotated by 90 °.

Table 2 shows the conditions for the film forming method of the electromagnetic noise suppressor having biaxial anisotropy.

[0044]

[Table 2]

Under the film forming conditions shown in Table 2, M (M is Fe, C
o, Ni, or their mixture) -X
(X is an element other than M and Y, or a mixture thereof) -Y (Y is any one of F, N, O, or a mixture thereof), and a soft magnetic thin film having a thickness of about several Formed in microns. Here, the composition is the same as that of the fourth embodiment, but as an example, the same elements as in Table 1 are selected. The composition of the soft magnetic thin film is the same as that of the fourth embodiment.
Represented by ₇₂ AL ₁₁ O ₁₇ .

The biaxial anisotropy is formed in the direction with the inclination angle β and the direction in which the substrate holder is rotated by 90 °. Here, it is appropriate to select an angle of 5 ° or less.

(Embodiment 6) FIG. 5 is an explanatory view of a method of manufacturing an electromagnetic noise absorber having uniaxial anisotropy according to Embodiment 6 of the present invention. In FIG. 5, 14 is a chamber of the sputtering apparatus, 11 is a sputtering target, 13 is a substrate holder, 12 is a substrate, and 15 is a plasma region. Here, the substrate holder 13 is inclined by an angle θ with respect to the plane direction of the sputtering target 11.
Therefore, the substrate is also inclined by the angle θ with respect to the plane direction of the sputtering target 11.

Table 3 shows the conditions for the film forming method of the electromagnetic noise suppressor having uniaxial anisotropy.

[0049]

[Table 3]

Under the film forming conditions shown in Table 3, M (M is Fe, C
o, Ni, or their mixture) -X
(X is an element other than M and Y, or a mixture thereof) -Y (Y is any one of F, N, O, or a mixture thereof), and a soft magnetic thin film having a thickness of about several Formed in microns. Here, M is Co and X is Z
The case where O is selected as r and Y is shown as an example. The composition of the soft magnetic thin film is represented by CoZrO or the like.
As X, in addition to Zr, Al, Ti, Si, C
Other elements such as a, Mg and Ge may be used, but an element having low toxicity is desirable from the environmental aspect.

The uniaxial anisotropy is formed in a direction with an inclination angle θ. Here, it is appropriate to select an angle θ of 5 ° or less.

(Embodiment 7) FIG. 6 is an explanatory view of a method of manufacturing an electromagnetic noise absorber having biaxial anisotropy according to Embodiment 7 of the present invention. FIG. 6A is an explanatory diagram of the manufacturing method of the first layer, and FIG. 6B is an explanatory diagram of the manufacturing method of the second layer.

In FIG. 6A, 14 is a chamber of a sputtering apparatus, 11 is a sputtering target, 13 is a substrate holder, 12 'is a substrate, and 15' is a plasma region. Here, the substrate holder 13 is inclined by an angle β with respect to the plane direction of the sputtering target 11. Therefore, the substrate is also inclined by the angle β with respect to the plane direction of the sputtering target 11.

FIG. 6B shows a state in which the substrate holder 13 in the state shown in FIG. 6A has been rotated by 90 °.

Table 4 shows the conditions for the film forming method of the electromagnetic noise suppressor having biaxial anisotropy.

[0056]

[Table 4]

Under the film forming conditions shown in Table 4, M (M is Fe, C
o, Ni, or their mixture) -X
(X is an element other than M and Y, or a mixture thereof) -Y (Y is any one of F, N, O, or a mixture thereof), and a soft magnetic thin film having a thickness of about several Formed in microns. Here, the composition is the same as that of the sixth embodiment, but as an example, the same elements as in Table 3 are selected. The composition of the soft magnetic thin film is similar to that of the sixth embodiment.
It is represented by ZrO.

The biaxial anisotropy is formed in the direction with the inclination angle β and the direction in which the substrate holder is rotated by 90 °. Here, it is appropriate to select an angle of 5 ° or less.

[0059]

As described above, according to the present invention, an electromagnetic noise suppressor having magnetic anisotropy that can obtain a noise absorbing effect in any shape regardless of the shape of the conductor pattern, and It is to provide the manufacturing method.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a usage state of an electromagnetic noise suppressor having magnetic anisotropy according to the first embodiment of the present invention.

FIG. 2 is a diagram showing noise absorption characteristics of an electromagnetic noise suppressor having magnetic anisotropy according to the present invention. 2A is a diagram showing the reflection amount versus frequency characteristic of the noise current, FIG. 2B is a diagram showing the transmission attenuation amount versus frequency characteristic of the noise current, and FIG. 2C is
The figure which shows the evaluation system which measured the noise absorption characteristic. Figure 2 (d)
FIG. 4 is a diagram showing magnetic permeability μ ″ vs. frequency characteristic.

FIG. 3 is an explanatory diagram of a usage state of an electromagnetic noise suppressor having magnetic anisotropy according to the second embodiment of the present invention. Figure 3 (a) shows
FIG. 3B is an external view of a single electromagnetic noise suppressor having magnetic anisotropy, and FIG. 3B is a diagram showing a state in which the electromagnetic noise suppressor having magnetic anisotropy is formed at a corner portion of an L-shaped conductor. .

FIG. 4 is an explanatory diagram of a usage state of an electromagnetic noise suppressor having magnetic anisotropy according to the third embodiment of the present invention.

FIG. 5 is an explanatory diagram of a method for manufacturing an electromagnetic noise absorber having uniaxial anisotropy according to the fourth and sixth embodiments of the present invention.

FIG. 6 is an explanatory diagram of a method for manufacturing an electromagnetic noise absorber having biaxial anisotropy according to the fifth and seventh embodiments of the present invention. FIG. 6A is an explanatory view of the manufacturing method of the first layer, FIG.
(B) is explanatory drawing of the manufacturing method of a 2nd layer.

FIG. 7 is an explanatory diagram of a usage state of a conventional isotropic electromagnetic noise suppressor. FIG. 7A is a diagram showing a case where the isotropic electromagnetic noise suppressor is rectangular, and FIG. 7B is a diagram showing a case where the isotropic electromagnetic noise suppressor is square.

[Explanation of symbols]

1,1a Uniaxial magnetic anisotropy Electromagnetic noise suppressor 2,4,5,7,31,32 Conductor 3,6,8 Biaxial magnetic anisotropic electromagnetic noise suppressor 11 Sputtering target 12,12 'substrate 13,13 'substrate holder 14 chambers 15,15 ', 15 "plasma region 21,22 isotropic electromagnetic noise suppressor 31,41 Conductor 32,33 coaxial cable 34 Insulating substrate 35 copper foil 36 Network Analyzer

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Michio Nemoto             6-7-1 Koriyama, Taihaku-ku, Sendai City, Miyagi Prefecture             Tokin Co., Ltd. F-term (reference) 5E040 CA13                 5E041 AA06 AA07                 5E049 AA04 BA11                 5E321 BB25 BB53 GG09

Claims (8)

[Claims] 1. M (M is any one of Fe, Co and Ni, or a mixture thereof) -X (X is M and Y)
Element other than or a mixture thereof) -Y (Y is
An electromagnetic noise suppressor comprising a soft magnetic thin film made of any one of F, N and O, or a mixture thereof, having magnetic anisotropy in a certain direction. 2. A first electromagnetic noise suppressor having magnetic anisotropy in a fixed direction, and a magnetic anisotropy forming a predetermined angle with the direction of magnetic anisotropy of the first electromagnetic noise suppressor. An electromagnetic noise suppressor comprising a laminated second electromagnetic noise suppressor. 3. The electromagnetic noise suppressor according to claim 2, wherein the predetermined angle is set to about 90 °. 4. The material of the electromagnetic noise suppressor is M (M
Is any one of Fe, Co and Ni, or a mixture thereof) -X (X is an element other than M and Y, or a mixture thereof) -Y (Y is any one of F, N and O) Or a mixture thereof) is a soft magnetic thin film, and the electromagnetic noise suppressor according to claim 2 or 3. 5. A method of manufacturing an electromagnetic noise suppressor having magnetic anisotropy in a linear direction, wherein the film-forming step is such that the plane direction of the substrate is relative to the plane direction of the target. A method for manufacturing an electromagnetic noise suppressor, wherein the electromagnetic noise suppressor is tilted by a predetermined angle in the direction of turning on. 6. A method of manufacturing a stacked electromagnetic noise suppressor having magnetic anisotropy in a plurality of directions, the manufacturing method comprising two film forming steps of forming a soft magnetic film on a substrate. The first film forming step is a film forming step in which the plane direction of the substrate is inclined by a predetermined angle with respect to the plane direction of the target in a direction in which one direction of magnetic anisotropy is imparted. The second second film forming step is a film forming step of inclining the plane direction of the substrate by a predetermined angle with respect to the plane direction of the target in a direction that imparts magnetic anisotropy in another direction. A method of manufacturing an electromagnetic noise suppressor, comprising: 7. The film forming step is performed in an argon atmosphere,
7. The method for manufacturing an electromagnetic noise suppressor according to claim 5, wherein the target is a sputter using iron and aluminum oxide. 8. The electromagnetic noise suppressor is M (M is F
e, Co, Ni, or their mixture)
-X (X is an element other than M and Y, or a mixture thereof) -Y (Y is any one of F, N, O, or a mixture thereof) is a soft magnetic thin film. The method for manufacturing an electromagnetic noise suppressor according to any one of claims 5 to 6.