JPS59202614A - Magnetic element - Google Patents

Abstract

PURPOSE:To contrive improvement in frequency characteristics in the high frequency region by a method wherein a specific constitution is accomplished using an amorphous material. CONSTITUTION:The composition of the titled magnetic element is indicated by the formula T100-x{M100-y-zGyR2}x. Said magnetic element is formed by alternately laminating a plurality of magnetic thin films of 100Angstrom <=D<=10,000Angstrom consisting of an amorphous alloy wherein x, y and z satisfy 1<=x<=50, 0<=y<=100.0, 0<=z<=100.0 and 0<=y+z<=100, and amorphous insulating films in thickness (d) of 10Angstrom <=d<=2,000Angstrom . T indicates a metal element or a mixture consisting of at least one kind of Fe, Co and Ni, M indicates a metal element or a mixture consisting of at least one kind of Sc, Y, La, Ti, Zr, Hf, Be, Cr, Ta, W, Nb, V, Mo, Mn and Cu, G indicates an element or a mixture consisting of at least a kind of B, Si, C, Al, Ge, Sn and Sb, and R indicates an element or a mixture consisting of at least Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Y.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic element such as a transformer, an inductor, or a magnetic head, and particularly to a magnetic element with improved frequency characteristics in a high frequency range.

In recent years, amorphous magnetic materials have attracted attention as magnetic core materials for this type of magnetic element. Amorphous magnetic materials have high magnetic permeability,
It has superior magnetic properties compared to conventional crystalline magnetic materials in terms of low coercive force, low magnetic loss, etc., and magnetic elements using n as the magnetic core have higher frequencies than conventional magnetic elements. Good characteristics. By the way, conventional amorphous magnetic materials are generally produced in the form of a thin strip by a liquid phase quenching method called a roller quenching method. It is usually 15 μm or more. In addition, since such materials are formed into magnetic cores by winding the above-mentioned thin strip-like material or stacking annular plates punched from the thin strip-like material, it is difficult to form the magnetic core IC during the manufacturing process. Even after formation, it was extremely difficult to control the magnetic domain structure by heat treatment or the like. Therefore, in a magnetic core using an amorphous material produced by the manufacturing method described above, eddy currents are likely to occur due to the thinness of the material, and the difficulty in controlling the magnetic domain structure causes the magnetization process to be affected by the motion of the domain walls. Because of this, the loss in the high frequency range increases rapidly, and as a result, the
There was a problem that it could only be used up to H1.

In order to solve the above problem, it is conceivable to form an amorphous material into a light-thin film by a vapor phase growth method such as a sputtering method or a vapor deposition method.

In this way, eddy currents can be reduced, and the demagnetizing field effect is also reduced, making control of the magnetic domain structure relatively easy. Therefore, if an amorphous material is formed into a thin film by a vapor phase growth method and a plurality of layers are laminated with a non-magnetic insulator interposed to form a magnetic core, the frequency is 410 MHz.
A magnetic element that can be used for CW to some extent can be obtained. However, even in this case, it is difficult to heat-treat the material in the shape of the magnetic core depending on the purpose of use, and the eddy current remains although it is reduced.
There was a problem in that the loss increased rapidly near MH2, making it impossible to use it at frequencies higher than that. Therefore, in order to further improve the frequency characteristics, it is conceivable to further reduce the thickness of the amorphous material used, but this
If the thickness is made to be less than μm, if the structure is constructed using the same concept as before, the basic magnetic properties will deteriorate due to the effects of island structures or substrate irregularities that occur during vapor phase growth, so it is necessary to improve the properties. I couldn't expect that.

SUMMARY OF THE INVENTION In view of the above-mentioned circumstances, it is an object of the present invention to provide a magnetic element that uses an amorphous material and has a novel configuration, and has better frequency characteristics in a high frequency range than conventional magnetic elements.

The magnetic element according to the present invention will be explained in detail below.

The magnetic core of the magnetic element according to the present invention is constructed by laminating a thin film of an amorphous alloy having a thickness within a specific range and a thin film of an insulating material having a thickness within another specific range. This not only suppresses eddy currents, but also utilizes magnetic interaction between thin films of amorphous alloy to improve frequency characteristics. In other words, in the above case, if the film thickness of the amorphous alloy is several thousand amps or less, and if the insulator floats in the hundreds, then the domain wall and Even if leakage flux occurs due to structural defects, this leakage flux will flow back through the amorphous alloy thin films on both sides.
As a result, the gradient of the energy potential of the domain wall and structural defects becomes gentler, and the thickness of the domain wall also increases. Therefore, if you configure as above,
The movement of domain walls becomes easier, and even if a defect such as an island structure is formed in a thin film of an amorphous alloy, the influence of this defect can be reduced.

Here, the composition of the amorphous alloy used in this invention will be described. This amorphous alloy is T100-Z”
It is represented by the composition formula 100-y-Z Gy"Z)Z, where T is a ferromagnetic metal that increases the magnetic saturation level at room temperature, for example, F6.
□, N1 (or a mixture of two or more of these is preferred). In order to increase the saturation magnetic flux density, the content of the ferromagnetic metal T is desirably 50 or more and 99 or less in terms of atomic chain. Furthermore, M is a metal required to adjust the magnetostrictive effect, such as sc, y,
La, 'ri, zr, Hf, Be, Cr,
Ta, W.

A metal element consisting of at least one of Nb, 141Mn, and Cu (or a mixture of two or more of these is preferred). This magnetostriction adjusting metal M has the effect of raising the crystallization temperature of the amorphous alloy, thereby providing thermal stability of the amorphous alloy. Furthermore, G is a metalloid element used to facilitate amorphization when a large amount of Co is used as the ferromagnetic metal T in this amorphous alloy, such as B, St, C, A#
, Ge, sn, and Sb.

In addition, R is used when instability such as a decrease in crystallization temperature occurs when a large amount of co is used.
For example, Ce, Pr, Nd, Pm, Sm, Eu
, Gd.

Tos D'ls Ho, Er, Tm, Yb,
It is an element consisting of at least one of Lu and Y. The content χ of the adjusting elements M, G, and R described above is 1 to 50% in terms of atomic weight. In this case, the magnetostriction adjusting metal M is an essential component, but the other elements G and R are each used as necessary. Therefore, the element GO content y and the element R content 2 for element M are:

0≦y<1o.

O≦z<100 0≦)'-1-Z<100 becomes.

By the way, since the magnetic element according to the present invention is mainly intended for use in a high frequency range, it is desirable that it can be made smaller and lower in power for coupling with semiconductor integrated circuits, etc. It must be able to withstand chemical or physical processing (e.g. stress application, high temperature heating, etc.). Therefore, the content χ#
3' tz is.

Each must be set to an appropriate value to optimize the improvement of saturation magnetic flux density by T, the magnetostriction adjustment by M, and the ease of chemical treatment and stabilization of magnetic properties at high temperatures by M, G, and H. .

Next, the material for the insulating film in this invention needs to be a non-magnetic insulator that can be easily formed into a thin film.
Examples include oxides such as 1021M203 or 40.

Next, a thin film of an amorphous alloy made of each of the above-mentioned compositions,
The laminated structure with the insulating film made of the above composition will be described in detail.

w, Figure 1 shows a case where a magnetic thin film of an amorphous alloy having a composition of Co87zr5Nb8 and formed by sputtering is used in a single layer structure, and a case where an insulating film of 50^ thickness made of 5IO2 is used between each layer. The thickness D of the magnetic thin film when used in a multilayer structure of four layers with
The changes in the antimagnetic strength of both of these were measured and plotted when the values were changed. As is clear from Fig. 1, the coercive force peak increases as the thickness D decreases for the thin layer structure shown by the chain line, but the coercive force peak increases even if the thickness D is reduced for the multilayer structure shown by the solid line. The coercive force Ha does not increase that much (with 100≦D, a low coercive force suitable for the magnetic element can be ensured.

Figure 2 shows the case where the same type of magnetic thin film as that used in the measurement in Figure 1 is used in a single layer structure, and the case where there is S between each layer.
10 with an insulating film of 100× thickness made of tO□ interposed
When using a multilayer structure of ~50 layers, the thickness D of the amorphous alloy is changed to increase the initial magnetic permeability μ0 of both of them.
was measured at an excitation frequency of lKH2. As is clear from this figure, in the case of the thin-layered structure shown by the chain line, μ0 decreases rapidly when the thickness D is less than 10000A, especially less than 5000μm, but in the case of the multilayered structure shown by the solid line, μ0 decreases only slightly. It is. In other words, in a multilayer structure, the magnetic properties are significantly improved due to the magnetic interaction between the magnetic thin films when the thickness D is 10,000 A or more and especially 5,000 A or less, although it also depends on the thickness d of the insulating film. Also, FIG. 3 shows a film having a thickness of 20 mm and having a composition of co, ozrlo and formed by a sputtering method.
Changes in coercive force Hc when the thickness of this insulating film, d, is varied in a two-layer structure of a thin film of 00A amorphous alloy with an insulating film made of SiO2 interposed between the eyebrows. is measured and plotted. As is clear from Figure 0, when the thickness d is less than 10A, the coercive force Hc increases rapidly.

Furthermore, FIG. 4 shows the thickness of the magnetic thin film of an amorphous alloy having a composition of Co87zr5Nb8, which has a multilayer structure with an insulating film of SiO□ and a thickness of 100 A interposed between the layers. D to 2 s o oX
In the case of a multilayer structure of 40 layers (shown by a solid line),
When the thickness D is 1 μm and the multilayer structure has 12 layers (
Magnetic permeability μ was measured by changing the excitation frequency f for each case (indicated by a dashed-dotted line), and when the thickness D was 2.7 μm and a multilayer structure of 4 layers (indicated by a dashed-double line). It is.

As is clear from this figure, if a magnetic thin film is made of two or more laminated layers, there will not be a large difference in characteristics depending on the number of laminated layers, but as for the thickness of the magnetic thin film, as the thickness D increases, , it can be seen that the magnetic permeability μ decreases in the high frequency range.

As is clear from the characteristics shown in Figures 1 to 4, when considering the thickness D of the magnetic thin film and the thickness d of the insulating film, if the thickness D is increased too much (for example, 100OOA As described above), it can be seen that the magnetic flux from the magnetic thin films on both sides stops penetrating in the middle part A in the thickness direction of the magnetic thin film, so the magnetic interaction decreases and the characteristics cannot be improved. Also, if the thickness D is made a little thinner (
If FJ is set to 1008 or less), the thickness d of the insulating film will increase relatively, and as a result, the obtained magnetic flux will decrease. Also, if the thickness d is increased too much, (
For example, if the current is 200 OA or more), the magnetic interaction between the magnetic thin films decreases and the characteristics deteriorate. Furthermore, if the thickness d is made too thin (for example, if it is less than IOA)
, the island-like structure of the insulating film becomes prominent and the insulating film loses its function as an insulating material, causing a cylindrical interaction, and the whole becomes like a single magnetic material, resulting in a significant deterioration of its properties. Therefore, the thickness D of the amorphous alloy thin film in this invention is:

100＾≦D≦10,0OOA Moreover, the thickness d of the insulating film is 10＾≦d≦2000λ It is desirable that

It should be noted that it seems that the multilayer structure as described above can be obtained by using a crystalline alloy such as Vermalloy as a magnetic thin film, but when such a crystalline alloy is used, (
b) Coercive force increases due to grain boundaries. (N) When heat treatment is performed, the multilayer structure is damaged due to interdiffusion. (C) Crystal growth is difficult to occur in vapor phase growth methods such as sputtering, so a thin film with strong mutual adhesion is formed. It is a well-known fact that problems arise, such as that it is difficult to do so.

Next, referring to the application of the magnetic element according to the present invention, the magnetic core of this magnetic element generates less eddy current and can significantly accelerate the motion of domain walls, so it has high magnetic permeability and low resistance in the high frequency range. It has excellent properties such as magnetic force, high squareness, and high-speed magnetization reversal characteristics. Therefore, this magnetic element can be used as a magnetic element in various devices that have hitherto been limited to an operating frequency of about several tens of KH2 due to the limits of the frequency characteristics of the magnetic element itself. These include devices that take advantage of the saturable nature of the magnetization process, its nonlinearity, and its ability to maintain magnetic flux levels;
Examples include magnetic elements in magnetic amplifiers, magnetic phase shifters, or parallel I/J amplifiers, and magnetic elements in Royer oscillators, switching power supplies, DC+DC converters, and the like. Further, by utilizing the reactance function and the electric energy conversion function, it can be configured as a high frequency inductor, transformer, or current transformer. Furthermore, a magnetic sensor can be constructed by utilizing high magnetic permeability and low coercive force. Examples of this magnetic sensor include a so-called magnetic head or a magnetic element for a mag-sototometer. Specifically, the above-described magnetic element for a magnetometer may be constructed by forming the laminate according to the present invention into a rod shape and winding the rod sufficiently.

Next, Example 1 of the present invention will be described in detail.

[Example 1] On the substrate, co. An amorphous alloy thin film with a composition of Zr3Nb5Nd2 and a thickness of 2500X, and SiO2.
An insulating film of 50× thickness consisting of 50 layers each was alternately laminated in sequence by sputtering. Next, an annular photoresist film with an inner diameter of 1.5u and an outer diameter of 3u is formed on the top surface, and etching is performed using this as a mask.
Further, the substrate was separated to obtain an annular magnetic core 1 as shown in FIG. Next, after heat-treating this magnetic core 1 at a temperature of 500°C for about 1 hour, as shown in the figure, Q, Q5
A magnetic element 3 was prepared by winding a 1 uφ copper wire 2 around 3 turns.

This magnetic element 3 can be used in a semiconductor-magnetic circuit with several hundred M
It worked well until H2. In addition, by adding Nb to the amorphous alloy thin film used in this magnetic element 3, corrosion resistance is improved, chemical processing is facilitated, and the crystallization temperature is increased. This made high-temperature heat treatment possible. Note that arrow 4 in FIG. 5 indicates the axis of easy magnetization of the amorphous alloy.

[Example 2] Co. Composed of YINb7Si2 and thickness 5o
ooi amorphous alloy thin film and SiO2 with a thickness of 10
10 layers each of 0A insulating films were alternately formed by sputtering.
This was laminated and processed into a ribbon shape. Next, the above is made of an insulating material and has an inner diameter of 1 mm and an outer diameter of 1.41 mm.
LIl! After wrapping 10 turns around the tubular body, cut into rings,
An annular magnetic core 5 having a thickness of 1 mm as shown in FIG. 6 was obtained. In this figure, 6 indicates the ribbon-shaped laminate, and 7 indicates the tubular body. Next, this magnetic core 5 is
After heat treatment at 0° C., the conductive wire was wound with 1 to 10 turns to produce a magnetic element. It has been confirmed that this magnetic element can be used as a microtransformer or inductor up to several hundred MHz. In this example, it is necessary to form the amorphous alloy into a ribbon shape by increasing the weight, and in order to prevent this from increasing the magnetostriction and reducing the range of the amorphous composition. y, st are added to.

[Example 3] Co85Y2Nb7W6 was deposited on a mirror-polished insulating substrate.
After forming a laminate of 20 layers of an amorphous alloy thin film having a thickness of 500X and sandwiching a 5102 film having a thickness of 50A, a protective layer of the same quality and size as the substrate was formed on the upper surface of the 5102 film. Next, the above-mentioned material was ground and lapped to obtain a magnetic core 8 for a magnetic head as shown in FIG. This magnetic core 8 is
Consisting of a magnetic core piece 9 on which a flat magnetic gap surface 9a is formed, and a magnetic core piece 11 on which two magnetic gap surfaces 11 a , 1 b separated by a notch 10 are formed. Then, on each magnetic core piece 9, 11,
12 is the substrate, 13 is the amorphous alloy, and 14 is the S
The iO□ film 15 is the protective layer. After each of these magnetic core pieces 9.11 is heat-treated, the surface 9a and the surface 11a are
, llb and glass melt S-a 1. After further heat treatment in a magnetic field, the conductive wire 16 was wound. In addition,
In the magnetic head 17 manufactured in this manner, a portion d! denoted by reference numeral 18! Forms a magnetic gap for recording and reproduction. The amorphous alloy in this example also has a magnetic head.

To improve the wear resistance as Nl), the crystal f
W was added to improve the heat temperature, and Y was added to adjust the magnetostriction. This magnetic head 17 can operate on signals up to several hundred MH2.

As is clear from the above description, the magnetic element according to the present invention is made of an amorphous alloy and has a thickness D of 100°A≦D.
It consists of a magnetic thin film in the range of ≦10.00 OA and a non-magnetic insulator, and the thickness d is IQA≦, ≦2. Since it has a magnetic core formed by alternately laminating a plurality of insulating films in the range of oooA, in addition to the effect of suppressing eddy currents in the magnetic core, it also suppresses the magnetic interaction between magnetic thin films ( Therefore, the movement of the magnetic layer can be made faster, thereby making it possible to realize a magnetic element that operates at a much higher frequency than conventionally used magnetic elements.

[Brief explanation of the drawing]

Figures 1 and 2 show the relationship between film thickness and coercive force, and the relationship between film thickness and magnetic permeability, respectively, when an amorphous alloy thin film is used as a thin layer or a multilayer. Fig. 3 is a characteristic diagram showing the relationship between the thickness of the insulating film and the coercive force when an amorphous alloy thin film is used as a multilayer body, and Fig. 4 is a characteristic diagram showing the relationship between the thickness of the insulating film and the coercive force when an amorphous alloy thin film is used as a multilayer body. In a laminate of amorphous alloy thin films,
A characteristic diagram showing the relationship between excitation frequency and magnetic permeability, FIG. 5 is a perspective view of the first embodiment of the invention, FIG. 6 is a perspective view of the second embodiment of the invention, and FIG. This is a perspective view of the third embodiment of this invention. 1...Magnetic core, 3...Magnetic element. Figure 3 Figure 4 υ. Figure 6

Claims (1)

[Claims] The compositional formula is T100-χ(Mloo-y-2GyR2)χ
, T is a metal element or a mixture consisting of at least one of Fe, Co, and Ni, M is Sc,
Y. La, Ti, Zr, Hf, Be, Cr,
Ta, W, Nb, V. A metal element or mixture consisting of at least one of Mo, Mn, and Cu, where G is B, Si, C, A
-13, Ge. Sn, an element or mixture consisting of at least one of 8b, R is Ce, Pr, Nd, Pm, Sm
tEu. Gd, 'rb, Dy, Ho, Er, Tm,
An element or mixture consisting of at least one of yb, Lu, and y, where Zr'I + Z is 1
Formed from an amorphous alloy that satisfies ≦χ<50・0≦y〈ku100, 0−z<100, 0≦y+z<100, the thickness D is 100X≦D
≦10.00 Magnetism in the OA range! ? ! membrane and thickness d
is IOA≦d≦2. 1. A magnetic element comprising a magnetic core formed by alternately laminating a plurality of magnetic thin films and insulating films, each consisting of a non-magnetic insulating film in the range oooA.