JPH09320020A - Magnetic head, method for manufacturing and reproducing magnetic head, and magnetic reproducing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable reproduction by a magnetic impedance effect of high sensitivity, and simplify the structure, by arranging a conductor penetrating a magnetic core in an insulated manner. SOLUTION: A conductor line 3 is set to penetrate a magnetic core 10 consisting of magnetic layers 1 and 2 at four points, which is capacitive-coupled via an insulating layer 4. An insulating film 7 is formed between the conductor line 3 and the magnetic layers 1, 2 so as to electrically insulate the conductor line 3 from the magnetic layers 1, 2. Electrode terminals 5, 6 are provided at both ends of the conductor line 3. When a constant a.c is fed to the conductor line 3 from the electrode terminals, a voltage value inversely proportional to the amount of an entering magnetic flux is output from a reproduction voltage output circuit. A magnetic head is accordingly reproduced in a manner responsive to the magnetic flux.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head for reproducing information recorded at high density, a method for manufacturing the same, a magnetic reproducing apparatus using the magnetic head, and a magnetic reproducing means.

[0002]

2. Description of the Related Art In recent years, the demand for a large-capacity magnetic recording device has expanded, and therefore, a magnetic head capable of recording information on a magnetic recording medium at a higher density and reproducing the information has been demanded. In response to such demands, a composite MR head using an MR head which is a read-only head having higher reproduction sensitivity than a widely used induction type head, particularly a thin film head, has been put into practical use. This composite MR head is
This is a head including an R head and a conventional inductive thin film head, and an MR head having a higher reproducing sensitivity is used during reproduction, and a conventional inductive thin film head is used during recording. Here, the MR head is a magnetoresistive effect element (MR: Ma).
It is a head using a gneteto-Resistance).

[0003]

However, a composite MR head using an MR element has a considerably more complicated head structure than a conventional inductive head.

Specifically, a magnetic gap for reproduction and a shield layer are required around the MR element, and a structure for providing a magnet for making the MR film into a single magnetic domain is required. A unique structure for applying a bias magnetic field is required to achieve proper reproduction.

Therefore, the production of the composite MR head requires a high degree of production technology, and there is a problem that it is difficult to secure a high yield.

In order to solve the above problems, the present invention provides a magnetic head having a relatively simple structure and a reproducing sensitivity superior to that of a conventional induction type head, a method of manufacturing the magnetic head, and a magnetic head thereof. It is an object to provide a reproducing method and a magnetic reproducing device used.

[0007]

In order to achieve the above-mentioned object, the invention according to claim 1 comprises a magnetic core composed of first and second soft magnetic layers and a conductor insulated in the magnetic core. Electrodes are provided at both ends of the conductor, and the conductor is insulated and arranged at at least a plurality of locations in the magnetic core.

According to the second aspect of the present invention, the conductor is capacitively coupled by sandwiching an insulating layer having a desired thickness in the conductor.

According to another aspect of the invention, the magnetic core is composed of first and second soft magnetic layers, and the conductor is a conductor layer which is disposed so as to be insulated from the first and second soft magnetic layers. And the capacitive coupling portion provided on the conductor is located outside the magnetic core.

The invention according to claim 4 is characterized in that the insulating layer forming the capacitive coupling is an oxide containing lead, lanthanum, zinc, and titanium as main components.

In the invention according to claim 5, the step of forming the first magnetic layer, the step of forming the first insulating layer, and the step of forming the first insulating layer, and the conductor on the first insulating layer A first conductor layer forming step of pattern-forming a part of the layer, a second insulating layer forming step of forming a second insulating layer, an insulating layer forming step which is a dielectric portion of capacitive coupling, and the conductor layer A second conductor layer forming step of patterning the remaining part of
It has a third insulating layer forming step of forming a third insulating layer on the conductor layer, and a second magnetic layer forming step of forming a second magnetic layer on the third insulating layer. It is characterized by

According to a sixth aspect of the present invention, there is provided a reproducing method using the head according to the second aspect, wherein the phase delay due to the inductance component of the conductor of the head and the phase advance due to the capacitance component are canceled. It is characterized in that the thickness of the insulating layer in the capacitive coupling portion is determined and the output is detected as a simple sum of impedance components of all conductors.

According to a seventh aspect of the present invention, there is provided a carrier signal generator for applying a constant-current high-frequency signal to the electrodes on both ends of the conductor, and bias magnetic field generating means for generating a bias magnetic field in the magnetic core. The magnetic head according to item 2 is used.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the magneto-impedance element according to the first aspect of the present invention, the magnetic core is magnetized by an external magnetic field, and the magnetic permeability of the magnetic core is changed, so that a high-frequency signal is applied between both ends of the conductor. The impedance value of changes. The voltage across the conductor changes based on the change in the impedance value of the conductor. Since the conductors are arranged in an insulating manner at a plurality of locations on the magnetic core, the detection sensitivity is increased.

According to the second and third aspects of the present invention, the delay of the impedance component can be canceled by the advance of the capacitance component by capacitively coupling the conductors.

In the invention according to claim 4, since the oxides containing lead, lanthanum, zinc, and titanium as the main components have a high relative dielectric constant, the thickness of the insulating layer can be controlled in the magnetic head of the present invention.

According to a fifth aspect of the invention, after forming the first magnetic layer, a first insulating layer is formed, and a part of the conductor layer is patterned on the first insulating layer, A second insulating layer is formed, a step of forming an insulating layer which is a dielectric portion for capacitive coupling and the remaining portion of the conductor layer are patterned.
Then, a third insulating layer is formed on the conductor layer, and a second magnetic layer is formed on the third insulating layer.

According to the invention of claim 6, the thickness of the insulating layer of the capacitive coupling portion is determined so that the phase delay due to the inductance component of the conductor of the head and the phase advance due to the capacitance component are canceled. The output is detected as the simple sum of the impedance components of all conductors.

According to the invention of claim 7, it is possible to provide a magnetic reproducing apparatus capable of high-sensitivity reproduction by mounting the magnetic head according to claim 4 by the magnetic impedance effect.

The first embodiment relating to the magnetic head of the present invention, the second embodiment relating to the method of manufacturing the magnetic head of the present invention, the third embodiment relating to the reproducing method of the present invention, and the magnetic reproducing of the present invention. A fourth example of the apparatus will be described.

First, a first embodiment relating to the magnetic head of the present invention will be described. 1 and 2 are views showing a first embodiment of a magnetic head of the present invention. The magnetic head comprises a first magnetic layer 1, a second magnetic layer 2, a conductor wire 3 and electrodes 5 and 6. The conductor lines are capacitively coupled with the insulating layer 4 in between.

The magnetic layers 1 and 2 are amorphous (Co--Co) composed of cobalt, zircon, niobium, and tantalum.
Zr-Nb-Ta) thin film. The film thickness of both the first and second magnetic layers is 1 μm.

The conductor wire 3 is provided at a position penetrating the magnetic core 10 composed of the magnetic layers 1 and 2 at four places, and each of them is capacitively coupled with the insulating layer 4 interposed therebetween. A Cu thin film or the like is used as the material. The insulating layer 4 is preferably a thin film having a high dielectric constant, and in Example 1, an oxide (PLZT) containing lead, lanthanum, zinc, and titanium as main components was used. In addition, the conductor wire 3 has an insulating film 7 formed between the conductor wire 3 and the magnetic layers 1 and 2 so as to be electrically insulated from the magnetic layers 1 and 2. As the insulating film 7, a SiO2 film was mainly used.

The electrode terminals 5 and 6 are electrodes provided at both ends of the conductor wire 3. The electrode terminal 5 and the electrode terminal 6 are terminals for flowing an alternating constant current, which will be described later, in the conductor wire 3.

FIG. 3 is an equivalent circuit diagram of a magnetic reproducing apparatus including the magnetic head of FIGS. This figure comprises an impedance element 21, a carrier signal generator 22, and a reproduction voltage output circuit 25.

The impedance element 21 is equivalent to the conductor wire 3 of the magnetic head shown in FIG. 1 as an impedance element. The terminal 23 and the terminal 24 correspond to the electrode terminals 5 and 6 shown in FIG. 1, respectively.

The carrier signal generator 22 generates a carrier signal which is a constant alternating current in the impedance element 21.

The reproduction voltage output circuit 25 measures the voltage generated between the terminals 23 and 24 and outputs it from the terminal 26.

Next, the reproducing operation of magnetic information will be described with reference to FIGS. When the magnetic core 10 including the magnetic layers 1 and 2 in the magnetic head shown in FIG. 1 is on the magnetization of magnetic information of the magnetic recording medium, a magnetic flux passes through the magnetic core. At this time, the magnetic core is magnetized by the magnetic flux, and the magnetic permeability is lowered. That is, the state is equivalent to that the impedance of the impedance element 21 in FIG. 3 is lowered. At this time, since an alternating constant current is applied to the conductor line 3, a counter electromotive voltage proportional to its impedance is generated between the terminals 23 and 24. After all, the reproduction voltage output circuit 2
The voltage value output from 5 is proportional to the impedance value, that is, the magnetic permeability.

Furthermore, it can be seen that the amount of inflowing magnetic flux, that is, a voltage value inversely proportional to the strength of magnetization is output from the reproduction voltage output circuit 25, and so-called magnetic flux response type reproduction is performed. . To increase the output voltage value, it is preferable that the impedance is high,
Further, it is desired that the magnetic field response is high. Therefore, the frequency should be as high as possible within the range where the magnetic permeability of the magnetic core is high.

As described above, the magnetic head of the present invention does not need to be provided with a magnetic gap for reproduction like the conventional composite MR head, and does not require a shield layer, which is a relatively simple structure. Thus, a magnetic flux response type reproducing head having a reproducing sensitivity superior to that of the conventional induction type head can be obtained.

Next, a second embodiment of the method of manufacturing the magnetic head of the present invention will be described.

FIGS. 4 and 5 are schematic cross-sectional views of the magnetic head for explaining the second embodiment and showing the manufacturing method of the first embodiment of the magnetic head of the present invention. FIG. 4 is a schematic sectional view when the magnetic head of the first embodiment shown in FIG. 2 is cut along line A, and FIG. 5 is a schematic sectional view when cut along line B.

The substrate 3 shown in FIGS. 4 (a) and 5 (a)
In No. 1, a mirror-finished alumina film is deposited on an alumina / titanium carbide (AlTiC) substrate. First
The magnetic layer 32 is formed by sputtering an amorphous alloy of Co-Zr-Nb-Ta.

4 (b) and 5 (b) show the first magnetic layer subjected to ion milling treatment.

FIGS. 4 (c) and 5 (c) show a case where a first insulating film 33 is formed by sputtering SiO2, and a Cu thin film or the like is sputtered thereon as a first conductor layer 34. is there.

4 (d) and 5 (d) show that SiO 2 is sputtered as the second insulating film 35 after being patterned by ion milling. The second insulating film 35 is the same SiO2 as the first insulating film 33.

4 (e) and 5 (e) show that after patterning the second insulating film 35 by ion milling,
A dielectric such as PLZT is sputtered to form an insulating layer 36, and a second conductor layer 37 is sputtered thereon. The second conductor layer 37 is made of the same material as the first conductor layer 34.

It is patterned by the ion milling treatment of FIGS. 4 (f) and 5 (f). Figure 5 (f)
As can be seen, the capacitive coupling portion 38 of the conductor is constructed.

4 (g) and 5 (g), the third insulating film 39 is formed by sputtering and then patterned by ion milling, and then the second magnetic layer 30 is formed by sputtering, and then dry or chemical etching is performed. It is a pattern.

Here, it is important that the insulating films 33, 35, 3 are
9 is smaller than the patterns of the first magnetic layer 32 and the second magnetic layer 30. The reason is to prevent the formation of a magnetic gap by the insulating layers 33, 35, 39 in the magnetic core. If a gap is formed here, the magnetic flux leaks from the magnetic recording medium at the time of reproduction, and the magnetic flux leaks when magnetizing the first and second magnetic layers, resulting in a loss and a reduction in reproduction efficiency. Further, the magnetic flux inside the magnetic layers 32 and 30 generated by the carrier signal current flowing through the conductor layers 34 and 37 during reproduction leaks from the gap formed on the surface of the magnetic core, and the magnetic flux magnetizes the magnetic recording medium. This is because there is a possibility that it will be done.

The manufacturing method and material of each layer are not limited to those described here. The material of the magnetic layer may be, for example, a NiFe alloy, a Co-based amorphous film, or a Fe-based film. As the manufacturing method, various thin film manufacturing methods such as vapor deposition, sputtering and plating may be used. The first magnetic layer and the second magnetic layer may be made of different materials.

In order to increase the magnetic permeability at high frequencies,
Multi-layering of the magnetic core is also effective.

Furthermore, the material of the substrate, the material of the protective film, and the manufacturing method are not limited to those in this embodiment.

Next, a third embodiment of the magnetic reproducing method and the magnetic reproducing apparatus will be described with reference to FIGS. 6 and 7. FIG. 6 is a conceptual diagram showing a magnetic reproducing apparatus of the present invention, and FIG. 7 is a diagram showing a recording / reproducing circuit particularly necessary for the magnetic reproducing apparatus of the present invention.

In FIG. 6, a magnetic head 400 is the same as the magnetic head of the present invention described in the first embodiment.
The magnetic head 400 is installed on a flying slider (not shown). Electrode terminals 43 and 44 are provided at both ends of a conductor wire 45 that is insulated and arranged so as to penetrate a magnetic core 46 composed of the first magnetic layer 41 and the second magnetic layer 42. A minute level DC current flows through the conductor wire 45 in order to bias magnetize the magnetic layers 41 and 42 in one direction.

The disk-shaped magnetic recording medium 40 is a so-called in-plane recording medium having a magnetic easy axis in the plane. The disk-shaped magnetic recording medium 40 has a film thickness of 0..0 as a recording layer on a glass disk having a very smooth surface.
A CoNiCr film having a thickness of 03 μm is deposited and has a diameter of 25 mm. In the magnetic information reproducing apparatus of this embodiment, the disk-shaped magnetic recording medium 40 is rotated in the direction of arrow A in FIG. 4 by a spindle motor or the like, and the magnetic head 400 floats above the disk-shaped medium to perform recording / reproduction. To do. Reference numeral 49 indicates a magnetization vector of magnetic information recorded on the disk-shaped magnetic recording medium 40.

FIG. 7 is a block diagram of the reproducing circuit of this embodiment. The reproducing apparatus includes a magnetic head 500, a carrier signal generator 55, a reproducing signal detecting circuit 56, a reproducing amplifier 57, and a reproducing signal processing circuit 58.

The magnetic head 500 is the equivalent circuit of the magnetic head 400 of the present invention. The magnetic head 500 has an impedance element 51. The impedance element 51 is an equivalent element of the conductor wire 45 provided on the magnetic core during reproduction. Electrode terminals 52 and 53 corresponding to the electrode terminals 43 and 44 of FIG. 6 are connected.

The carrier signal generator 55 supplies an alternating constant current, which is a carrier signal, to the impedance element 51 via the electrode terminals 52 and 53 during reproduction. Although not shown, a minute current is passed through the conductor wire 45 to generate a bias magnetic field. The carrier signal generator 55 includes a carrier signal oscillating circuit, a constant current drive circuit, and a circuit for supplying a direct current to the conductor wire. The frequency of the carrier signal is, for example, 500 MHz.

The reproduction signal detection circuit 56 is composed of an AM detection circuit (not shown) and an AM demodulation circuit (not shown). The AM detection circuit detects a signal between the electrode terminal 52 and the electrode terminal 53. The AM demodulation circuit demodulates the AM wave detected by the AM detection circuit and outputs a signal to be originally reproduced.

The reproduction amplifier 57 includes a reproduction signal detection circuit 56.
The reproduced signal demodulated by is amplified. Reproduction signal processing circuit 5
Reference numeral 8 converts the reproduction signal amplified by the reproduction amplifier 57 into a signal suitable for output. For example, code demodulation is performed. The converted signal is output from the output terminal 59.

Next, the reproducing operation of the magnetic reproducing apparatus of this embodiment will be described with reference to FIGS. 6 and 7. First, the magnetic head 400 shown in FIG. 6 scans the recording magnetization 49 on the disk-shaped magnetic recording medium 40. When the recording magnetization 49 is scanned, the leakage magnetic flux from the recording magnetization 49 passes through the magnetic core 46 composed of the magnetic layers 41 and 42. The magnetic core 46 is magnetized by the magnetic flux, and its magnetic permeability decreases.

On the other hand, a carrier signal current of 2 MHz is made to flow between the electrode terminals 43 and 44 by the carrier signal generator 55 shown in FIG. 7, and the signal voltage V between the electrode terminals 43 and 44 which changes depending on the current. Is V = ZI (where I
Is a constant), the impedance Z between the electrode terminals is
Is determined by The impedance Z has a relationship in which the impedance Z decreases as the magnetic permeability of the magnetic core 46 decreases. That is, the impedance Z decreases when the leakage magnetic field from the magnetic recording medium is large, and the impedance Z increases when the leakage magnetic field is small. For example, as shown in FIG. 8, it is assumed that the stray magnetic field of the magnetic recording medium read by the magnetic head fluctuates in the range of −a to + a. Here, the polarity of − + indicates the direction of the magnetic field. Then, as shown in FIG. 9, when the external magnetic field Hext which is the leakage magnetic field from the magnetic recording medium is 0, the impedance Z takes a large value b2 and the leakage magnetic field is -a or When it is + a, it takes a small value b2.

However, the level of this impedance value is
Although it is inversely proportional to the strength of the leakage magnetic field from the recording magnetization 49, it has nothing to do with the polarity of the recording magnetization 49. If the amount of magnetic flux passing through the core is the same, the signal voltage between the electrode terminals 43 and 44 will be the same.

Therefore, since the recording magnetization cannot be reproduced by any signal processing as it is, the magnetic core is DC bias magnetized in one direction in order to change the impedance value depending on the polarity of the recording magnetization. . Specifically, for example, a small amount of direct current (flown from the carrier signal generator 55 shown in FIG. 7) is passed through the conductor wire 45 shown in FIG. 6 to direct-bias magnetize the magnetic core in one direction. As a result, the signal voltage changes according to the polarity of the recording magnetization 49. FIG. 10 shows the size d
6 is a diagram showing the relationship between the impedance Z and the external magnetic field Hext when a bias magnetic field of negative polarity is applied in FIG. FIG.
It can be seen that the curve moves to the right by the bias magnetic field d. Regarding the value of the impedance Z, when the leakage magnetic field from the magnetic recording medium is −a, the impedance value takes the minimum value c3, and when the leakage magnetic field is 0, the value of the impedance Z takes the intermediate value c2, and the leakage magnetic field When is + a, the impedance value reflects the polarity of the external magnetic field, as can be seen from the maximum value c1.

In this way, the voltage that changes based on the impedance value that changes based on the external magnetic field and the carrier signal current appears at the electrode terminals 52 and 53.

Here, since the magnetic head 400 scans the recording magnetizations having different polarities and different lengths one after another, the voltage change between the electrode terminals 52 and 53 causes an AM wave whose carrier is the carrier signal current. Become. This AM wave is demodulated as a reproduction signal in the reproduction signal detection circuit 56 and output to the reproduction amplifier 57. The reproduction amplifier 57 amplifies the demodulated reproduction signal and outputs it to the reproduction signal processing circuit 58.
The reproduction signal processing circuit 58 converts the reproduction signal into a signal suitable for output, and outputs the signal from an output terminal 59.

Here, the absolute value of the impedance Z is expressed by (Equation 1).

[0060]

[Equation 1]

Since the output is proportional to Z as described above,
To obtain a high output, ZI of each conductor penetrating the magnetic core may simply be added. However, since the impedance Z of the conductor 45 of the magnetic head 400 of the present invention penetrating the magnetic core at four places is delayed by the inductance (L) component and advanced by the capacitance (C) component, there is a phase shift between the conductors. Occurs. Therefore, the thickness of the insulating layer 48 of the capacitive coupling portion 47 of the magnetic head 400 is determined so as to cancel the phase delay due to the L component and the phase advance due to the C component, as shown in (Equation 2).

[0062]

[Equation 2]

By performing such processing, ZI is the sum of ZI (1-4) of the conductors penetrating at four places, that is, ZI = ZI (1) + ZI (2) + ZI (3) + ZI.
It becomes (4).

A method of obtaining the thickness of the insulating layer 48 from (Equation 2) will be described. (Equation 3) shows capacitance.

[0065]

(Equation 3)

The impedance is assumed as shown in (Equation 4).

[0067]

(Equation 4)

The number of surrogates in the equation is shown in FIG. Here, since the conductor 45 is copper, the relative magnetic permeability is 1. The relative dielectric constant of the insulating layer PLZT is 2300. The area S of the insulating surface was 50 μm × 25 μm. The cross-sectional area of the conductor 45 is 2
The size was 5 μm × 1 micron. Therefore r2 is 2 microns. r1 was 100 μm. Carrier frequency is 50
0 MHz. The thickness of the insulating layer 48 was set to 7 nm by substituting (Equation 3) and (Equation 4) into (Equation 2). In the examples, the insulating layer 4 is formed by measuring the film thickness after forming PLZT by sputtering and selecting the film thickness of 7 nm.
The thickness of 8 was controlled.

By thus canceling the phase delay due to the L component and the phase advance due to the C component, the output can be detected as a simple sum of the impedance components of all conductors, and the accuracy is improved. be able to.

As described above, recording is performed by the conventional method using the magneto-impedance element of the present invention,
Since the reproduction is performed by the magnetic impedance element, it is not necessary to provide a magnetic gap for reproduction like a conventional composite MR head, and a shield layer is not necessary. A magnetic flux response type magnetic recording / reproducing head superior to the induction type head can be obtained.

The materials for the magnetic core and the like are not limited to those described here. The material may be, for example, a Co-based amorphous film or a Fe-based film. The magnetic core of the magnetic head and the magnetic core of the magnetic impedance element may be made of the same material.

In order to increase the magnetic permeability at high frequencies,
Multi-layering of the magnetic core of the magneto-impedance element is also effective.

Further, the shape of the magnetic head is not limited to the shape shown in this embodiment. The magneto-impedance element may be arranged in another portion of the magnetic core other than this embodiment as long as the easy axis of magnetization of the magnetic core is parallel to the magnetic flux in the magnetic core of the magnetic head.

[0074]

The magnetic head according to the first aspect of the present invention has a structure in which the conductors penetrating the magnetic core are arranged in an insulating manner, and has a simpler structure than the MR head, so the manufacturing process is also simpler. In addition, it is easy to secure a relatively high yield and is excellent in mass productivity. Further, it becomes possible to reproduce by the magneto-impedance effect having higher sensitivity than before.
Further, since the conductors are arranged in a through insulation manner at a plurality of positions of the magnetic core, higher sensitivity can be achieved. Further, since it is a magnetic flux response type like the conventional MR head, it is possible to cope with the speed reduction due to the miniaturization of the recording / reproducing apparatus.

According to the second and third aspects of the present invention, by capacitively coupling the conductors, the delay of the impedance component can be canceled by the advance of the capacitance component, and a highly sensitive head can be provided.

According to the fourth aspect of the invention, since the oxide containing lead, lanthanum, zinc, and titanium as the main components has a high relative dielectric constant, the thickness of the insulating layer can be controlled in the magnetic head of the present invention.

According to the fifth aspect of the present invention, the capacitive coupling can be performed accurately by forming the conductor in two steps.

According to the sixth aspect of the invention, the thickness of the insulating layer in the capacitive coupling portion is determined so that the phase delay due to the inductance component of the head conductor and the phase lead due to the capacitance component cancel each other. The output can be detected as a simple sum of the impedance components of the conductors, and high sensitivity can be easily achieved.

According to the seventh aspect of the present invention, by mounting the magnetic head of the present invention, reproduction by the magnetic impedance effect is possible, and the reproduction sensitivity is superior to that of the conventional inductive head. Further, since it is of the magnetic flux response type like the conventional MR head, it is possible to provide a magnetic reproducing apparatus which can cope with a reduction in speed due to downsizing of the recording and reproducing apparatus.

[Brief description of drawings]

FIG. 1 is an external view of a magnetic head of the present invention.

FIG. 2 is an external view of a magnetic head of the present invention.

FIG. 3 is an equivalent circuit diagram of the magnetic head of the present invention.

FIG. 4 is a sectional view for explaining the manufacturing method according to the second embodiment of the present invention.

FIG. 5 is a sectional view for explaining the manufacturing method according to the second embodiment of the present invention.

FIG. 6 is a conceptual diagram of a magnetic reproducing apparatus of the present invention.

FIG. 7 is a block diagram of a magnetic reproducing apparatus of the present invention.

FIG. 8 is a diagram showing changes over time in the leakage magnetic field from the medium.

FIG. 9 is a diagram showing a relationship between an external magnetic field and impedance when a bias magnetic field is not applied.

FIG. 10 is a diagram showing a relationship between an external magnetic field and impedance when a bias magnetic field is applied.

FIG. 11 is a schematic view showing a magnetic head of the present invention.

[Explanation of symbols]

 1 1st magnetic layer 2 2nd magnetic layer 3 Conductor wire 4 Insulating layer 5,6 Electrode terminal 7 Insulating film 21 Impedance element 22 Carrier signal generator 23, 24 Electrode terminal 25 Reproduction voltage output circuit 26 Terminal 31 Substrate 32th First magnetic layer 33 First insulating film 34 Conductor layer 35 Second insulating film 36 Insulating layer 37 Second magnetic layer 38 Capacitive coupling portion 39 Third insulating film 30 Second magnetic layer 400 Magnetic head 40 Disk shape Magnetic recording medium 41 First magnetic layer 42 Second magnetic layer 43 Electrode terminal 44 Electrode terminal 45 Conductor wire 46 Magnetic core 47 Capacitive coupling portion 48 Insulating layer 49 Magnetic information magnetization vector 500 Magnetic head 51 Impedance element 52, 53 Electrode Terminal 55 Carrier signal generator 56 Reproduction signal detection circuit 57 Reproduction amplifier 58 Reproduction signal processing circuit 59 Output terminal

Claims (7)

[Claims] 1. A magnetic core composed of first and second soft magnetic layers and a conductor insulated in the magnetic core, and electrodes are provided at both ends of the conductor, wherein the conductor is at least in the magnetic core. A magnetic head characterized by being insulatedly arranged at a plurality of locations. 2. The magnetic head according to claim 1, wherein the conductor is capacitively coupled by sandwiching an insulating layer having a desired thickness in the conductor. 3. The magnetic core is composed of first and second soft magnetic layers, and the conductor is a conductor layer which is disposed so as to be insulated from the first and second soft magnetic layers. 3. The magnetic head according to claim 2, wherein the provided capacitive coupling portion is located outside the magnetic core. 4. The magnetic head according to claim 3, wherein the insulating layer forming the capacitive coupling is an oxide containing lead, lanthanum, zinc, and titanium as main components. 5. A step of forming the first magnetic layer, a step of forming a first insulating layer, and a step of forming a part of the conductor layer on the first insulating layer. A first conductor layer forming step of forming a pattern, and a second forming of a second insulating layer
Of the insulating layer, the step of forming an insulating layer which is a dielectric portion for capacitive coupling, the step of forming a second conductor layer for patterning the remaining portion of the conductor layer, and the third insulating layer on the conductor layer. 4. A third insulating layer forming step of forming a layer, and a second magnetic layer forming step of forming a second magnetic layer on the third insulating layer. Magnetic head manufacturing method. 6. A reproducing method using a head according to claim 2, wherein insulation of the capacitive coupling portion is performed so that a phase delay due to an inductance component of the conductor of the head and a phase advance due to a capacitance component cancel each other out. A reproducing method characterized by determining the layer thickness and detecting the output as a simple sum of impedance components of all conductors. 7. A magnetic field generator according to claim 2, further comprising a carrier signal generator for applying a constant-current high-frequency signal to electrodes on both ends of the conductor, and bias magnetic field generating means for generating a bias magnetic field in the magnetic core. A magnetic reproducing device characterized by using a head.