JPH08285930A - Magnetism detection element and magnetic head - Google Patents

Abstract

PURPOSE: To provide a constitution in which a high output is obtained stably, whose manufacture is easy and which can be manufactured at low costs in a magnetism detection element which makes use of a magnetic impedance effect. CONSTITUTION: A magnetism detection element is constituted in such a way that a high-permeability magnetic film 12, an insulating film 13, a conductive film 16, an insulating film 14' and a high-permeability magnetic film 12' are laminated sequentially from the lower part on a nonmagnetic substrate 10. At least one out of the magnetic films 12, 12' is endowed with magnetic anisotropy in such a way that an easy direction of magnetization becomes a direction perpendicular, inside a film face, to a magnetic-field detection direction. In the conductive film 16, a plurality of straight line parts along the magnetic-field detection direction are arranged in parallel at prescribed intervals, they are connected sequentially so as to be turned up, and they are formed to be a zigzag pattern in which they are electrically connected in series. A high-frequency current is applied across terminal parts 16A, 16B at both ends of the conductive film 16, and a change in an impedance generated across the terminal parts 16A, 16B by an external magnetic field Hex is converted into an electric signal so as to obtain an output.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic detecting element for detecting a magnetic field and a magnetic head for reproducing magnetically recorded information recorded on a magnetic recording medium, and more particularly to a magnetic detecting element and a magnetic element utilizing a magnetic impedance effect. It is about the head.

[0002]

2. Description of the Related Art Recently, magnetic sensors have been diversified with the rapid development of information equipment, measurement / control equipment, etc.
Further miniaturization and higher precision are expected in the future.

In the field of magnetic heads, downsizing of digital magnetic recording devices is progressing. For example, in a conventional inductive magnetic head in a hard disk of an external storage device of a computer or a digital compact cassette (DCC) of digital audio. An MR element (magnetoresistive effect element) is used for the reproducing head because the S / N is lowered due to the decrease of the track width and the relative speed. But MR
The element does not depend on the speed of the medium and is suitable for taking out the output at low speed, but since the resistance change rate is only a few percent, it is hoped to develop an element with higher sensitivity for future high density. It is rare.

Also in the field of sensors such as magnetic encoders, the magnetic flux leaking to the outside is extremely reduced due to the reduction of the magnetization pitch of the magnetizing medium, and the sensitivity insufficiency is becoming a problem even in MR elements.

Therefore, what has recently attracted attention is an element utilizing the magneto-impedance effect (hereinafter, abbreviated as MI effect) by an amorphous wire disclosed in Japanese Patent Laid-Open No. 6-281712. The MI effect is that when a high frequency current in the MHz band is applied to a magnetic material, the impedance of the magnetic material changes due to an external magnetic field, which causes the amplitude of the voltage across the magnetic material to change by several tens of percent with a minute magnetic field of several Gauss. It is a phenomenon.

The advantage of the element utilizing the MI effect is that it is not excited in the lengthwise direction of the magnetic substance, so that there is no influence of the demagnetizing field, the length of the element can be shortened to about 1 mm or less, and it is suitable for downsizing. The resolution of magnetic flux detection is 0.1 Oe for MR element
The high sensitivity of about 10 ^-5 Oe is obtained with respect to the low sensitivity of. Further, the amount of impedance change is about 3% in the MR element, whereas the element using the MI effect can be changed in the order of several tens of percent.

[0007]

The function of the element due to the MI effect was found in the amorphous wire, and the amorphous wire is excellent in productivity as a material. However, when dealing with minute magnetization like a magnetic head, since the cross section is circular and the diameter can be reduced to only about 30 microns, an appropriate shape can be obtained at the magnetic recording medium contact portion corresponding to the magnetic gap of the induction type magnetic head. Not be
The required track width cannot be obtained and the thickness corresponding to the gap width cannot be obtained.

As shown in FIG. 8, the magnetic recording medium 8
With the minute magnetization of 1, the magnetic flux easily circulates, and since the magnetic detection element 82 utilizing the MI effect is arranged perpendicular to the medium 81, the magnetic flux density decreases as it goes deeper into the magnetic detection element 82. This causes a problem that the sensitivity (impedance change amount) of the entire device cannot be obtained. If the length of the element is shortened, the sensitivity of the entire element is improved, but the absolute value of the impedance itself is reduced, the voltage at both ends or the output of the LC oscillation circuit is reduced, and the operation becomes unstable.

Further, in terms of handling, the amorphous wire is easily bent when the diameter is several tens of microns, and it is difficult to position and take out terminals, and there is a problem that the element is not easily manufactured.

Therefore, an object of the present invention is to solve the above problems in a magnetic detecting element and a magnetic head utilizing the MI effect, to obtain a stable and high output, and to have no problem in handling the element body. It is an object of the present invention to provide a structure that can be easily manufactured, and in particular, in a magnetic head, a track width can be set as desired at a medium contact portion of a magnetic body corresponding to a magnetic gap, and a thickness corresponding to the gap width can also be set as desired.

[0011]

In order to solve the above-mentioned problems, according to the present invention, there is provided a magnetic detection element utilizing a magneto-impedance effect, which has a first high magnetic permeability in order from the bottom on a non-magnetic substrate. A magnetic film, a first insulating film, a conductive film, a second insulating film, and a second high-permeability magnetic film are laminated to form at least one of the first and second high-permeability magnetic films. Magnetic anisotropy is applied so that the easy axis of magnetization is perpendicular to the magnetic field detection direction in the film plane, and the conductive film has a plurality of linear portions parallel to each other at predetermined intervals along the magnetic field detection direction. Formed in a zigzag pattern that is connected in series and folded back in sequence and electrically connected in series, and a high-frequency current is applied from both ends of the conductive film, and an impedance generated between both ends of the conductive film by an external magnetic field. Change to electric signal and output Configuration was obtained as to the employed.

Further, according to the present invention, there is provided a reproducing magnetic head utilizing the magneto-impedance effect, wherein a tip end surface of the non-magnetic substrate is formed as a sliding surface of a magnetic recording medium, and the head surface is substantially different from the sliding surface. The first high-permeability magnetic film, the first insulating film, the conductive film, the second insulating film, and the second high-permeability magnetic film are arranged in this order from the bottom on the vertical upper surface.
Of the high permeability magnetic film are laminated, and the first and second
At least one of the high-permeability magnetic films is provided with magnetic anisotropy so that the easy axis of magnetization is in a direction substantially parallel to the sliding surface within the film surface, and the first high-permeability magnetic film is formed. An end portion of is exposed to the sliding surface, the conductive film, a plurality of linear portions along a direction substantially perpendicular to the sliding surface are arranged in parallel at a predetermined interval, are connected so as to be sequentially folded back, Formed in a zigzag pattern electrically connected in series, a high-frequency current is applied from both ends of the conductive film, and a change in impedance generated between both ends of the conductive film by a magnetic field from a magnetic recording medium is converted into an electric signal. We adopted a configuration that can be converted to obtain playback output.

[0013]

According to the above structure of the magnetic detecting element, the MI effect is obtained by the first and second high-permeability magnetic films and the conductive film.
Magnetic detection can be performed. In particular, by forming the conductive film into a zigzag pattern, even if the length of the element body composed of the magnetic film and the conductive film in the magnetic field detection direction is shortened in order to increase the sensitivity, the absolute value of the impedance can be earned and stable. High output can be obtained.

Further, since the element body is composed of the above-mentioned thin films formed on the non-magnetic substrate, there is no problem in handling such as an amorphous wire.

Further, according to the structure of the magnetic head, a stable and high output can be obtained by the same operation as that of the magnetic detecting element. Further, the thickness corresponding to the track width and the gap width can be set as desired by setting the width and thickness of the end portion of the first high-permeability magnetic film exposed on the medium sliding surface.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment] FIGS. 1 to 3 show a first embodiment of the present invention.
As an example, an example of a magnetic detection element utilizing the MI effect will be described. First, FIG. 1 shows the structure of the entire element.

In the structure of the magnetic sensing element shown in FIG. 1, the rectangular first high-permeability magnetic film 12 is formed on the upper surface of the non-magnetic substrate 10.
Is formed, the first insulating film 14 is laminated thereon, and the conductive film 16 having a zigzag pattern is further formed thereon.
Are formed. Then, a second insulating film 14 'is further formed thereon, and a rectangular second high-permeability magnetic film 12' is laminated on the second insulating film 14 '. A rectangular terminal portion 16A is provided at both ends of the zigzag pattern of the conductive film 16.
16B are formed, and external wiring (not shown) for taking out the output of the element is connected to the terminal portions 16A and 16B by soldering or wire bonding.

With this structure, when a high frequency current is applied to the conductive film 16 from the terminal portions 16A and 16B at both ends, the impedance between the terminal portions 16A and 16B of the conductive film 16 is changed by the external magnetic field Hex, and this change is electrically changed. It is designed to be converted into a signal and output.

Next, the details of each component of the element will be described. First, the non-magnetic substrate 10 is formed of calcium titanate (Ti-Ca based ceramic), oxide glass, titania, alumina, or the like.

The high permeability magnetic films 12 and 12 'are made of Fe--Co.
A magnetic film such as a -B system amorphous film, a Fe-C system, and a Fe-N system microcrystalline film is formed by a vacuum film forming technique. At least one of the high-permeability magnetic films 12 and 12 ′ has an easy axis of magnetization in the direction of arrow B in the drawing, which is a direction perpendicular to the magnetic field detection direction in which the external magnetic field Hex is applied.
After film formation, magnetic anisotropy is provided by cooling in a magnetic field.
Both the magnetic films 12 and 12 ′ are indicated by arrows B in the easy magnetization axis direction.
It is desirable to have magnetic anisotropy in the direction, but there is no problem if at least one magnetic anisotropy is secured in order to obtain the MI effect. If the thicknesses of the magnetic films 12 and 12 'are too thin, the MI effect is lowered, and if they are too thick, the impedance is lowered. Therefore, it is preferable to set the thickness between 1 μm and 20 μm.

The insulating films 14 and 14 'are made of SiO ₂ , Cr ₂ O.
An oxide insulating film of ₃ , TiO ₂ or the like is formed by a vacuum film forming technique or the like. The thickness of the insulating films 14 and 14 ′ is a gap of the magnetic circuit formed by the upper and lower two layers of high magnetic permeability magnetic films 12 and 12 ′, each of which has an insulating effect of 0.05 μm.
Is the lower limit, and the upper limit is preferably 1 μm or less so that the inductance value generated between the high-permeability magnetic films 12 and 12 ′ and the conductive film 16 does not become small.

The conductive film 16 formed on the insulating film 14 is
It is made of Cu, Au or the like having a low specific resistance and is formed in the pattern shown in FIG. That is, in the pattern of the conductive film 16, a plurality of straight line portions having a predetermined length along the magnetic field detection direction, which is the direction in which the external magnetic field Hex is applied, are arranged in parallel at predetermined intervals, and adjacent straight line portions are sequentially folded. The end portions are bent and connected vertically as folded portions 16C and 16D, and as a whole, a zigzag folded pattern electrically connected in series is formed. In addition, as described above, the rectangular terminal portions 16A are formed on both ends of the zigzag pattern of the conductive film 16.
16B is formed.

Next, FIG. 3 shows a cross section of the device taken along the line AA 'in FIG. As shown in FIG. 3, the conductive film 16
The directions of the currents flowing in the straight line portions 161 to 164 are opposite to each other in the straight line portions adjacent to each other, so that the reflux magnetic fluxes generated in the high permeability magnetic films 12 and 12 'are indicated by reference numerals 20A to 20D. Reverse rotation loops are formed alternately. By forming a small magnetic path around each of the linear portions of the conductive film 16 like the return magnetic fluxes 20A to 20D, the inductance per conductive film 16 increases and the length of the conductive film 16 due to the zigzag folding. In addition to the effect of earning a profit, the magnetic films 12, 12 ', the insulating films 14, 1
Even if the length of the element body made of 4'and the conductive film 16 in the magnetic field detection direction is short, a large inductance can be obtained and an absolute value of impedance can be obtained. Further, the length of the element body in the magnetic field detection direction can be made almost as short as that of the MR element, and an excellent MI effect can be exhibited even for minute magnetization.

The folded portions 16C and 16D at both ends of the zigzag pattern of the conductive film 16 shown in FIG. 2 generate a magnetic field in the same direction as the external magnetic field Hex detection direction by passing a current through the conductive film 16. But the folded portions 16C, 16D
Is located outside the high-permeability magnetic film 12.
By determining the size and arrangement of 6 and the high permeability magnetic film 12,
The interference of magnetic flux in the high-permeability magnetic film 12 is suppressed. Similarly for the high permeability magnetic film 12 ', the folded portion 16
Although C and 16D may be located outside, it is not always necessary. Folded portion 16 of conductive film 16
Two layers of high-permeability magnetic films 12, 12 'for C and 16D
If at least one of the above is not applied, the clear reflux magnetic flux as shown in FIG. 3 cannot be generated in that portion, so that the sensitivity of the element is not affected.

Next, the results of testing the characteristics of the magnetic sensing element of this embodiment as described above will be described. The high-permeability magnetic films 12 and 12 'are Fe-Ta-C based magnetic films having a thickness of 0.2 mm x 0.2 mm and a thickness of 5 µm, and the insulating films 14 and 14' have a thickness of 0.1 µm. And The conductive film 16 was formed with a thickness of 1 μm, a zigzag number of 7 times, a linear portion width of 10 μm, and a linear portion spacing of 10 μm.

The impedance change is measured by the conductive film 16
A high-frequency current of 100 MHz was passed through and the change in voltage across both ends was examined. External magnetic field is applied by Helmholtz coil, ± 2
It was changed in the range of 5 Oe.

As a result, first, the inductance at 100 MHz was 62 nH, and the Q value at that time was 8.2. On the other hand, in the case of the conventional Fe-Co-B amorphous wire having a diameter of 30 μm, L45nH, Q5.
In the device of this example, the length was as short as 0.2 mm and high values for both L and Q were obtained. The amount of change in impedance is 68 in the external magnetic field of 8 Oe in the element of this embodiment.
% Impedance change, indicating a good change.

As described above, the element of this embodiment has a large amount of change in impedance and high sensitivity, and moreover, the absolute value of impedance can be secured by gaining the inductance, and stable high output can be obtained. Further, since the element body of the magnetic detection element of the present example is formed of a thin film formed on a non-magnetic substrate, there is a problem of bending and positioning like an element using an amorphous wire in the element body, and it is difficult to take out terminals. It is easy to manufacture without problems such as size. Also,
After forming a thin film of a plurality of element bodies on a common non-magnetic substrate, the non-magnetic substrate can be cut to manufacture a large number of elements at a time, so-called multi-cavity production is possible.

[Second Embodiment] Next, a second embodiment of the magnetic head for reproduction which is a modification of the structure of the first embodiment will be described with reference to FIGS. 4 to 7, parts common to or corresponding to those in FIGS. 1 to 3 of the first embodiment are designated by common reference numerals, and description of common parts will be omitted.

In order to modify the structure of the magnetic sensing element of FIG. 1 of the first embodiment into a reproducing magnetic head, the first high magnetic permeability magnetic film 12 is formed on the non-magnetic substrate 10 as shown in FIG. Extend to the edge of the tip surface. Then, the magnetic film 12 and the other film 1
Non-magnetic substrate 10 having 2 ', 14, 14' and 16 formed thereon
Is formed as a medium sliding surface 10A on which an unillustrated magnetic recording medium (hereinafter abbreviated as a medium) slides, and the tip of the high-permeability magnetic film 12 is formed on the medium sliding surface 10A. The part should be exposed and in contact with the medium. The medium sliding direction is perpendicular to the film surface of the high-permeability magnetic film 12 as indicated by the arrow. The thickness of the tip of the magnetic film 12 exposed on the medium sliding surface 10A corresponds to the gap width of the magnetic gap of the inductive magnetic head, and the width of the tip of the magnetic film 12 becomes the track width.

Due to the positional relationship with the medium sliding surface 10A, the easy axis of magnetization of the arrow B of at least one of the magnetic films 12 and 12 'is parallel to the medium sliding surface 10A within the film surface. Further, the direction of the zigzag pattern of the conductive film 16 is such that the parallel straight line portions are along the direction perpendicular to the medium sliding surface 10A.

When the conductive film 16 contacts the medium, the high-frequency current applied to the conductive film 16 flows out to the medium side. Therefore, the medium sliding surface 10 on the upper surface of the non-magnetic substrate 10 is exposed.
It is arranged so as to be separated from A.

The second high-permeability magnetic film 12 'is separated from the medium sliding surface 10A on the upper surface of the non-magnetic substrate 10 and the folded portions 16C at both ends of the zigzag-shaped pattern of the conductive film 16 are formed. The layout and size are determined so that it does not overlap with 16D.

Under such a structure, at the time of reproduction, the medium (not shown) slides on the medium sliding surface 10A, and a high frequency current is applied to the conductive film 16 from the terminal portions 16A and 16B at both ends. By doing so, the impedance between the terminal portions 16A and 16B of the conductive film 16 changes due to the magnetic field from the recording magnetization of the medium, and this change is converted into an electric signal to obtain a reproduction output. The magnetic head of this embodiment can obtain high sensitivity and impedance by the same operation as that of the first embodiment, and a stable and high reproduction output can be obtained. Further, similarly, the manufacturing is easy, and a large number can be taken.

In the magnetic head of this embodiment, the track width can be set as desired by setting the width of the tip of the magnetic film 12 exposed on the medium sliding surface 10A. For example, when the track width is made narrower than the entire width of the magnetic film 12,
As shown in FIG. 5, the medium sliding surface 1 of the high permeability magnetic film 12 is shown.
By narrowing the width of the tip exposed at 0A toward the sliding surface and making the width Wt of the tip smaller than the entire width Wm of the magnetic film 12, a narrow track width Wt can be dealt with.

Further, the thickness corresponding to the gap width of the induction type magnetic head can be set as desired by setting the thickness of the tip portion of the magnetic film 12 exposed on the medium sliding surface 10A. For example, as shown in FIG. 6, the thickness Tg of the tip portion of the magnetic film 12 exposed on the medium sliding surface 10A is made thinner than the thickness Tm of the remaining portion of the conductive film 16 to correspond to the gap width. It is also possible to reduce the thickness and improve the shape loss due to minute magnetization.

In each of the magnetic heads shown in FIGS. 4 to 6, since the magnetic film 12 exposed on the medium sliding surface 10A is insulated from the conductive film 16 by the insulating film 14, the conductive film 1
There is no concern that the high-frequency current applied to 6 will flow out to the medium side through the magnetic film 12.

Further, the magnetic films 12, 12 ', the insulating film 14,
A multi-track head can be easily constructed by arranging a plurality of element bodies composed of 14 'and the conductive film 16 on the upper surface of the non-magnetic substrate 10 as shown in FIG. In this case, since the facing area between the adjacent element bodies is very small, crosstalk can be prevented.

[Third Embodiment] FIG. 9 shows a magnetic sensing element of a third embodiment in which the structure of the terminals of the first embodiment is modified. In the present embodiment, in the zigzag pattern of the conductive film 16, the terminal portions 16A and 16B are formed continuously at both ends on the side opposite to the magnetic detection side to which the external magnetic field Hex is applied, and in addition, in the middle portion. A terminal portion 16E, which is a center tap, is formed continuously with the folded portion 16D.
According to this configuration, it is possible to connect to the output circuit so that the impedance change of the element can be taken out in two.

Specifically, in the multivibrator type oscillation circuit shown in FIG. 10, for example, the center tap terminal portion 16E is connected to the power source + E, and the terminal portions 16A, 1 at both ends are connected.
6B is connected to the oscillator circuit side. In this configuration, since the impedance change obtained by dividing the element into two parts is utilized, the characteristics of the two oscillating parts become extremely symmetrical, and a stable output can be obtained.

When the oscillator circuit is connected and used, a DC bias magnetic field is required for the magnetic detection element along the external magnetic field detection direction, but a bias magnet or a DC magnetic field application coil is used. The bias magnetic field may be applied by arranging the bias magnetic field with respect to the magnetic detection element. As a specific arrangement, in the case of a magnet, it may be arranged above the detection element or behind the terminals 16A, 16B, 16E, and in the case of a coil, it may be arranged so as to surround the periphery of the detection element. Alternatively, it may be formed on the detection element as a pattern of one elongated conductive film.

Also in the device of this embodiment, the first high magnetic permeability magnetic film 12 is provided on the non-magnetic substrate 10 in the structure of FIG.
The magnetic head for reproduction can be constructed by extending the end surface of the non-magnetic substrate 10 as the medium sliding surface 10A.

[0044]

As is apparent from the above description, according to the magnetic sensing element of the present invention, the first high magnetic permeability magnetic film, the first insulating film, the conductive film, By forming a conductive film in a zigzag pattern with a structure in which a second insulating film and a second high-permeability magnetic film are laminated, the absolute value of the impedance is obtained even if the length of the element body in the magnetic field detection direction is shortened. Can be ensured, the impedance change efficiency of the entire element with respect to minute magnetization can be improved, and stable high output can be obtained. In addition, the problems of cross-sectional shape and handling, which the conventional amorphous wire could not cope with minute magnetization, can be solved, the manufacturing is easy, and a large number can be taken, and the cost can be provided at low cost. In addition, since the length of the element in the magnetic field detection direction can be shortened to almost the same level as MR, an excellent MI effect can be exhibited even for minute magnetization, and new applications can be expanded in place of the MR element.

Further, according to the magnetic head of the present invention, the end portion of the first high-permeability magnetic film is exposed on the medium sliding surface of the non-magnetic substrate with the same structure as the magnetic detecting element of the present invention. With the structure, a stable and high reproduction output can be obtained similarly to the magnetic detection element of the present invention, the manufacture is easy, a large number of pieces can be obtained, and the device can be provided at low cost. In addition, it is easy to use multiple heads. Further, by setting the width and thickness of the end portion of the first high-permeability magnetic film exposed on the medium sliding surface, the thickness corresponding to the track width and the gap width can be set as desired, which is an excellent application range. The effect is obtained.

[Brief description of drawings]

FIG. 1 is a perspective view showing a structure of a magnetic detection element according to a first embodiment of the present invention.

FIG. 2 is a plan view showing a zigzag pattern of a conductive film of the magnetic detection element.

FIG. 3 is a cross-sectional view taken along the line AA ′ in FIG. 1, showing a return magnetic flux due to a current applied to the conductive film of the magnetic detection element.

FIG. 4 is a perspective view showing the structure of a magnetic head according to a second embodiment of the invention.

FIG. 5 is a perspective view showing a structure of a modified example of the magnetic head corresponding to a narrow track width.

FIG. 6 is a cross-sectional view showing the structure of a modified example in which the thickness of the magnetic film tip portion exposed on the medium sliding surface of the magnetic head is thin.

FIG. 7 is a perspective view showing a modified example configured as a multi-track head.

FIG. 8 is an explanatory diagram showing how a magnetic flux is applied from a magnetic recording medium to a magnetic detection element.

FIG. 9 is a perspective view showing the structure of the magnetic detection element of the third embodiment.

FIG. 10 is a circuit diagram of a multivibrator type oscillation circuit to which the detection element is connected.

[Explanation of symbols]

 10 Non-magnetic Substrate 12, 12 'High Permeability Magnetic Film 14, 14' Insulating Film 16 Conductive Film 16A, 16B, 16E Terminal Part 16C, 16D Folding Part

Claims (11)

[Claims] 1. A magnetic sensing element utilizing a magneto-impedance effect, comprising a first high-permeability magnetic film and a first magnetic film on a non-magnetic substrate in order from the bottom.
Of the insulating film, the conductive film, the second insulating film, and the second high-permeability magnetic film are laminated, and at least one of the first and second high-permeability magnetic films is
Magnetic anisotropy is added so that the easy axis of magnetization is perpendicular to the magnetic field detection direction in the film plane, and the conductive film has a plurality of linear portions parallel to each other at predetermined intervals along the magnetic field detection direction. Formed in a zigzag pattern that is connected in series and folded back in series and electrically connected in series. A high-frequency current is applied from both ends of the conductive film, and an impedance is generated between both ends of the conductive film by an external magnetic field. A magnetic detection element characterized in that a change in the electric field is converted into an electric signal to obtain an output. 2. The at least one of the first and second high-permeability magnetic films is arranged so as not to overlap the folded-back portion at the end of the zigzag pattern of the conductive film. 1. The magnetic detection element according to 1. 3. The magnetic detecting element according to claim 1, wherein each of the first and second insulating films has a thickness of 0.05 μm to 1 μm. 4. The magnetic detection element according to claim 1, wherein each of the first and second high-permeability magnetic films has a thickness of 1 μm to 20 μm. . 5. A terminal portion is formed at each of both ends of the meandering pattern of the conductive film, and a terminal portion as a center tap is formed continuously to the folded portion in the middle portion. Claims 1 to 4
The magnetic detection element according to any one of 1 to 6 above. 6. A reproducing magnetic head utilizing a magneto-impedance effect, wherein a top surface of a non-magnetic substrate having a tip surface formed as a sliding surface of a magnetic recording medium is substantially perpendicular to the sliding surface from below. A first high-permeability magnetic film, a first insulating film, a conductive film, a second insulating film, and a second high-permeability magnetic film are laminated in this order, and the first and second high-permeability magnetic films are formed. At least one of the magnetic films is
Magnetic anisotropy is applied so that the easy axis of magnetization is in a direction substantially parallel to the sliding surface within the film surface, and the end portion of the first high-permeability magnetic film is exposed on the sliding surface. The conductive film is formed in a zigzag pattern in which a plurality of straight line portions along a direction substantially perpendicular to the sliding surface are arranged in parallel at a predetermined interval, are sequentially folded, and are electrically connected in series. A high frequency current is applied from both ends of the conductive film, and a change in impedance generated between the both ends of the conductive film by a magnetic field from a magnetic recording medium is converted into an electric signal so that a reproduction output can be obtained. A magnetic head characterized in that 7. The magnetic head according to claim 6, wherein the width of the end of the first high-permeability magnetic film exposed on the sliding surface is narrowed toward the sliding surface. . 8. The thickness of an end of the first high magnetic permeability magnetic film exposed on the sliding surface is smaller than the thickness of a portion of the conductive film. The magnetic head described in 1. 9. The first and second high permeability magnetic films, the first
9. The magnetic head according to claim 6, wherein a plurality of element bodies each composed of a second insulating film and a conductive film are arranged in parallel on the upper surface of the non-magnetic substrate. 10. A terminal portion is formed on each of both ends of the meandering pattern of the conductive film, and
The magnetic head according to any one of claims 6 to 9, wherein a terminal portion as a center tap is formed continuously with the folded portion of the intermediate portion. 11. The magnetic head according to claim 10, wherein the terminal portion as the center tap is connected to a power source, and the terminal portions at both ends are connected to a multivibrator type oscillation circuit.