JP3210139B2 - Magnetoresistive magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetoresistive head used in a magnetic recording / reproducing apparatus and a method of manufacturing the same.

[0002]

2. Description of the Related Art In recent years, there has been a demand for an external recording device for a computer to have a small size and a large capacity. However, in order to realize a small and large capacity of an external recording device using magnetic recording, linear recording is required. In addition to increasing the density, it is also necessary to increase the track density. In response to these demands, a magnetoresistive effect type magnetic head using a magnetoresistive element capable of obtaining a high output without depending on the medium speed and obtaining a high track density has been used at present. .

A conventional magnetoresistive head using a magnetoresistive element and a method of manufacturing the same will be described below. FIG. 6 is a configuration diagram of the magnetoresistive head as viewed from the magnetic recording medium side. 1 is a magnetoresistive element portion,
It is formed on the lower insulating layer 2 formed on the lower shield 3. The lower insulating layer 2 has a role of magnetically separating the magnetoresistive element portion 1 and the lower shield 3, and is formed by depositing an oxide such as SiO ₂ or Al ₂ O ₃ by a vacuum deposition method such as evaporation or sputtering. The magnetoresistive element 1 is formed on the lower insulating layer 2 by vacuum deposition such as evaporation or sputtering. The magnetoresistive element section 1 is an element that exhibits a change in resistance to an external magnetic field, and is made of an Fe-Ni alloy or a Co-Ni alloy.
These films are tens of nanometers to increase sensitivity to external magnetism.
The following particularly thin films are used: The magnetoresistive element section 1 is composed of a soft magnetic bias film, a nonmagnetic film, and a magnetoresistive film, and is formed by a vacuum film forming method such as a vacuum deposition method, a sputtering method, and an ion beam sputtering method. A conductor layer 5 for supplying a current to the element portion and detecting a change in the voltage is in contact with the magnetoresistive element portion 1 at a portion outside the magnetic flux detection width A. For the conductor layer 5, Au, Al, Cu, W or a laminated film thereof is used as a good conductor having a low resistance value, and is formed by a vacuum film forming method such as a vacuum evaporation method, a sputtering method, an ion beam sputtering method, and a CVD method. Filmed.

In the magnetoresistive element formed as described above, the soft magnetic bias film is magnetized by the supplied current, and the magnetization becomes a bias for inclining the magnetization of the magnetoresistive film at a predetermined angle. The ratio of Bs * δ between the saturation magnetic flux density Bs and the film thickness δ of the magnetoresistive films is determined so that the bias is optimal. Therefore, in order to bias the magnetoresistive film stably and optimally with the soft magnetic bias film, it is necessary to saturate the soft magnetic bias film with the magnetic field due to the current. A current value that generates a magnetic field equal to or greater than the magnetic field Hk. This is reflected in the vertical symmetry of the reproduced output waveform. As shown in FIG. 10, increasing the sense current of the head improves the vertical symmetry of the output waveform, and the magnetic field generated by the sense current becomes soft magnetic. After the bias film reaches Hk or more and saturates, the vertical ratio of the waveform becomes 100
It is stable at%.

[0005] On the magnetoresistive element portion 1 thus formed, on the insulating layer 4 for protecting the magnetoresistive element and on the conductor layer 5, an upper insulating layer 6 is formed by an oxide such as SiO ₂ or Al ₂ O ₃ . Is formed by vacuum evaporation such as evaporation or sputtering.
Thereafter, a soft magnetic material such as permalloy, sendust or the like having a width equal to or greater than the magnetic flux detection width A of the magnetoresistive element is formed as an upper shield 7 on the upper insulating layer 6 by a vacuum evaporation method such as evaporation or sputtering or a plating method. Film.

A recording gap 8 is formed on the upper surface of the upper shield 7 by vacuum deposition such as evaporation or sputtering of an oxide such as SiO ₂ or Al ₂ O ₃ . On the recording gap 8, a recording core 9 is formed by depositing a soft magnetic material such as permalloy or sendust by a vacuum deposition method such as evaporation or sputtering or a plating method, and is etched into a predetermined shape by a physical or chemical method. You. In FIG. 6, the magnetic flux detection width of the magnetoresistive element portion 1 for reproducing is the width indicated by A, the recording core width B for recording, and the recording is indicated by C between the recording core 9 and the upper shield 7. Is performed in the area where In this structure, the distance between the lower shield 3 and the upper shield 7 which affects the frequency characteristics in the magnetic flux detection width A of the magnetoresistive element due to the step generated by the thickness of the magnetoresistive element portion 1 and the conductor layer 5 is D. The case of E is mixed.

Further, recording is performed in the area of the recording core width B in the area C, but the recording gap 8 is not straight as shown in the figure. FIG. 7 shows a perspective view of these element portions.

FIGS. 8A to 8C show a method of manufacturing these elements.
(D), as shown in FIGS. 9 (a) to 9 (c). FIG.
8A, a lower insulating layer 2 is provided on a lower shield 3 and a magnetoresistive element 1 is formed thereon.
As shown in (b), an insulating layer 4 for protecting the magnetoresistive element is provided, and a conductor layer 5 is formed (FIG. 8C). Thereafter, an upper insulating layer 6 is provided (FIG. 8D), and an upper shield 7 is formed (FIG. 9A). A recording gap 8 is formed thereon (FIG. 9B), and a recording core 9 is formed thereon (FIG. 9).
(C)). FIG. 10A shows the result of measuring the sense current dependency of the upper / lower ratio of the output waveform by performing recording / reproduction with this magnetoresistive head, and FIG. 11B shows the result of measuring the linear recording density dependency of the output. Shown in

[0009]

However, in the above-mentioned conventional configuration, the problem that the optimum sense current value for realizing the good vertical symmetry of the reproduced waveform is large and the step F of the conductor layer 5 in the magnetic flux detection region are caused by the following problems. In FIG. 6, there are two types of shield distances indicated by D and E, and the waveform reproduced in this structure is obtained by superposition of two types of reproduced waveforms, so that the output is remarkable due to waveform interference at a high recording density. The step F (FIG. 6) caused by the step of the magnetoresistive element 1 is widened and the recording core 9 is widened, and if the step F is applied to the step, the linearity of the recording gap 8 is impaired together with the step F on the magnetic flux detection width A. Also, there is a problem that the output is significantly reduced due to waveform interference at a high recording density.

An object of the present invention is to provide a magnetoresistive magnetic head capable of reducing an optimum sense current value and obtaining high resolution even at a high recording density, and a method of manufacturing the same. With the goal.

[0011]

In order to achieve this object, a magnetoresistive head according to the present invention comprises a lower shield.
Laminating a magnetoresistive film on the layer via a first insulating layer,
A soft magnetic bias is applied to the magnetoresistive film via a non-magnetic insulating layer.
A magneto-resistance effect type magnetic head provided with an ass film, wherein a length of the soft magnetic bias film on the medium facing surface is shorter than a length of the magneto-resistance effect film, and a second magnetic head is provided on the soft magnetic bias film . 2 and a conductor layer formed on the magnetoresistive film, wherein the second insulation layer and the conductor layer have the same height, and the second insulation layer and the second insulation layer have the same height.
An upper shield layer is provided on the conductor layer via a third insulating layer.
Between the upper shield layer and the lower shield layer.
The intervals were uniform.

[0012]

According to the present invention, the anisotropic magnetic field of the soft magnetic bias film of the magnetoresistive element portion can be reduced and the magnetic shield interval in the magnetic flux detecting region can be kept constant. The recording gap can be formed linearly, thereby reducing the optimal sense current value.
High resolution can be obtained at a high recording density.

[0013]

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

FIG. 1 is a configuration diagram of a magneto-resistance effect type magnetic head viewed from a magnetic recording medium side. The lower shield 3 has a width at least equal to the magnetic flux detection width A of the magnetoresistive element, and is formed of a soft magnetic material such as permalloy or sendust by a vacuum film forming method or a plating method, or a soft magnetic material such as ferrite. . Lower insulating layer 2 on lower shield 3
And has a role of magnetically separating the magnetoresistive element portion 1 and the lower shield 3, and is formed by depositing an oxide such as SiO ₂ or Al ₂ O ₃ by vacuum deposition such as evaporation or sputtering.

On the lower insulating layer 2, the magnetoresistive element portion 1 is formed in the order of a magnetoresistive film 12, a nonmagnetic film 13, and a soft magnetic bias film 14 by vacuum evaporation such as evaporation or sputtering. The magnetoresistive element 1 is an element that exhibits a change in resistance to an external magnetic field.
i-based alloys and the like are used, and these films are particularly thin films of several tens nm or less in order to increase sensitivity to an external magnetic field.
The film is formed by a vacuum film forming method such as a vacuum evaporation method, a sputtering method, and an ion beam sputtering method. A conductor layer 5 for supplying a current to the magnetoresistive element section 1 and detecting a change in the voltage is formed thereon except for the detection width of the magnetoresistive element. For the conductor layer 5, Au, Al, Cu, W or a laminated film thereof is used as a good conductor having a low resistance value, and is formed by a vacuum film forming method such as a vacuum evaporation method, a sputtering method, an ion beam sputtering method, and a CVD method. Filmed.

The magnetoresistive element portion 1 and the conductor layer 5
SiO as upper insulating layer 6_TwoAnd Al_TwoO _ThreeSteam oxides
It is formed by vacuum deposition such as deposition or sputtering. So
Then, as an upper shield 7 on these upper insulating layers 6
It has a width at least equal to the magnetic flux detection width A of the magnetoresistive element.
Vapor deposition of soft magnetic materials such as permalloy and sendust
Film formation by vacuum deposition method such as sputtering or plating method
You. A recording gap 8 is formed on the upper surface of these upper shields 7.
SiO_TwoAnd Al_TwoO_ThreeSuch as evaporation or sputtering of oxides
The film is formed by a vacuum deposition method. Next, the recording gap 8
The recording core 9 is made of a soft magnetic material such as permalloy or sendust.
Vacuum deposition method such as evaporation or sputtering
Films are formed by the key method and physically or chemically formed into a predetermined shape.
Engraved by the method.

In FIG. 1, the magnetic flux detection width of the magnetoresistive element portion 1 for performing reproduction is a width indicated by A, the recording core width for performing recording is B, and recording is performed between the recording core width B and the upper shield 7. Is performed in the area indicated by C between In this structure, a step generated by the thickness of the magnetoresistive element portion 1 and the conductor layer 5 and a magnetic flux detection width A of the magnetoresistive element
In this case, the distance between the shields that affects the frequency characteristics is a uniform distance of D. Further, recording is performed in the area of C having the recording core width B, and the recording gap 8 is straight as shown in the figure. FIG. 2 shows a perspective view of these element portions.

The method of manufacturing these devices is shown in FIGS.
4 (e) and FIGS. 4 (a) to 4 (e). As shown in FIG. 3A, a lower insulating layer 2 is provided on a lower shield 3, and a magnetoresistive element portion 1 is formed thereon in the order of a magnetoresistive element film, a nonmagnetic film 13, and a soft magnetic bias film 14. Next, an oxide insulating layer 4 is entirely formed to a predetermined thickness by a vacuum film forming method such as vapor deposition or sputtering, and is processed into a predetermined shape by etching. Next, as shown in FIG. 3 (b), after the etching prevention material 10 is formed except for the portion which becomes the contact with the conductor layer 5, the insulating layer 4 at the contact portion is removed by etching. The etching stopper 10 is removed as shown in FIG. A photosensitive resin generally used in photolithography is used for the etching stopper 10.

Thereafter, as shown in FIG. 3D, the soft magnetic bias film 1 at a contact portion with the conductor layer 5 of the magnetoresistive element portion 1 is formed.
4 and the entire surface is etched to remove the non-magnetic film 13,
At this time, since the etching speed ratio of the oxide insulating layer 4 and the metal magnetoresistive element 1 is about 1: 2, the insulating layer 4 remains at the same thickness as the magnetoresistive film 12 by this etching. To be determined. Since the etching speed ratio changes depending on the etching conditions, various selections can be made together with the thickness of the insulating layer depending on the thickness of the magnetoresistive element film.

Thereafter, the conductor layer 5 is formed to a height equal to that of the insulating layer 4 (FIG. 3E), and an etching stopper 11 is formed thereon in a predetermined shape of the conductor of the magnetoresistive element (FIG. 3E). FIG.
(A)). Further, by removing unnecessary portions of the conductor layer 5 by etching and removing the etching preventing material 11, FIG.
A flat surface without a step as shown in FIG.

FIG. 5 shows a magnetoresistive element of this embodiment and a conventional example. In the conventional configuration, as shown in FIG. 5B, the magnetoresistive element is laminated in the order of the magnetoresistive film 12, the non-magnetic film 13, and the soft magnetic bias film 14, and the insulating layer 4 having the detection width of the magnetoresistive element is formed. After the formation, in order to form the conductor layer 5, the shapes of the magnetoresistive film 12 and the soft magnetic bias film 14 become equal, the aspect ratio of the film is approximately 10: 1, and the surface on which the insulating layer 4 is formed is formed. On the contrary, in the configuration of the present embodiment, the magnetoresistive film 12, the nonmagnetic film 13, and the soft magnetic bias film 14 are stacked in this order, as shown in FIG. After forming the insulating layer 4 having the detection width, the soft magnetic bias film 14 and the nonmagnetic film 13 at the contact portion of the conductive layer 5 are removed by etching, and the conductive layer 5 having the same thickness as the insulating layer 4 is formed. In order to remove the unnecessary portion by etching, a contact between the soft magnetic bias film 14 and the conductor layer 5 is formed. Since minute can be removed film aspect ratio approximately 1: 1 and the surface forming an insulating layer 4 thereon is flat. For this reason, the anisotropic magnetic field Hk of the soft magnetic bias film 14 has conventionally been increased by the influence of the film shape, but in the present embodiment, there is no influence of the shape anisotropy caused by the film shape. A soft magnetic bias film 14 having a small Hk is obtained.

Thereafter, an upper insulating layer 6 is provided (FIG. 4).
(C)), the upper shield 7 is formed (FIG. 4D).
Further, a recording gap 8 is formed thereon, and a recording core 9 is formed thereon (FIG. 4E). By adopting such a method, a structure in which the gap between the shields is uniform in the magnetic flux detection width A of the magnetoresistive element can be obtained, and the recording gap 8 formed thereabove can be formed linearly.

FIG. 10C shows the result of measuring the sense current dependency of the up / down ratio of the reproduced waveform, and FIG. 10C shows the result of measuring the linear recording density characteristic of the output. This is shown in 11d. In the magnetoresistive head of this embodiment, the shape of the soft magnetic bias film 14 is approximately 1: 1 as shown in FIG. 10 and there is no influence of the shape anisotropy. Therefore, the optimum sense current value was reduced, and furthermore, the detection area of the magnetoresistive element was flat and the recording gap 8 was flat as shown in FIG. 11, so that the output reduction due to waveform interference was reduced, and high resolution at high recording density was obtained. You can see that.

[0024]

According to the present invention, the anisotropic magnetic field caused by the shape anisotropy of the soft magnetic bias film in the magnetoresistive element portion is small, the magnetic flux detecting region is flat, and the recording formed thereon is performed. A magnetoresistive head having a flat gap can be obtained. As a result, an excellent vertical ratio of the reproduced waveform can be obtained at a low current, and therefore, a magnetoresistive head capable of obtaining high resolution at a high recording density with low power consumption and small heat generation can be realized.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a magnetoresistive element portion of a magnetoresistive magnetic head according to an embodiment of the present invention.

FIG. 2 is a perspective view of a magnetoresistive head according to an embodiment of the present invention.

3A is a view showing a manufacturing process of a magnetoresistive head according to an embodiment of the present invention; FIG. 3B is a diagram showing a manufacturing process of a magnetoresistive head according to an embodiment of the present invention; Manufacturing process diagram of a magnetoresistive magnetic head according to one embodiment. (D) Manufacturing process diagram of a magnetoresistive magnetic head according to an embodiment of the present invention. (E) Magnetoresistive magnetic head according to an embodiment of the present invention. Manufacturing process diagram

4A is a view showing a manufacturing process of a magnetoresistive head according to an embodiment of the present invention; FIG. 4B is a diagram showing a manufacturing process of a magnetoresistive head according to an embodiment of the present invention; Manufacturing process diagram of a magnetoresistive magnetic head according to one embodiment. (D) Manufacturing process diagram of a magnetoresistive magnetic head according to an embodiment of the present invention. (E) Magnetoresistive magnetic head according to an embodiment of the present invention. Manufacturing process diagram

5A is a structural view of a magnetoresistive element according to an embodiment of the present invention. FIG. 5B is a structural view of a conventional magnetoresistive element.

FIG. 6 is a configuration diagram of a conventional magnetoresistance effect type magnetic head.

FIG. 7 is a perspective view of a conventional magnetoresistive head.

8A is a manufacturing process diagram of a conventional magnetoresistive magnetic head. FIG. 8B is a manufacturing process diagram of a conventional magnetoresistive magnetic head. FIG. 8C is a manufacturing process diagram of a conventional magnetoresistive magnetic head. d) Manufacturing process diagram of conventional magnetoresistive head

9A is a manufacturing process diagram of a conventional magnetoresistive magnetic head, FIG. 9B is a manufacturing process diagram of a conventional magnetoresistive magnetic head, and FIG. 9C is a manufacturing process diagram of a conventional magnetoresistive magnetic head.

FIG. 10 is a diagram showing the dependence of the upper / lower ratio of the reproduced waveform on the sense current in one embodiment of the present invention and a conventional example

FIG. 11 is a diagram showing linear recording density dependence of output in one embodiment of the present invention and a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Magnetoresistance element part 4 Insulating layer 5 Conductive layer 9 Recording core 12 Magnetoresistance film 13 Nonmagnetic film 14 Soft magnetic bias film

Claims (1)

(57) [Claims] 1. A magnetoresistive effect type wherein a magnetoresistive film is laminated on a lower shield layer via a first insulating layer, and a soft magnetic bias film is provided on the magnetoresistive effect film via a nonmagnetic insulating layer. A magnetic head, wherein a length of the soft magnetic bias film on the medium facing surface is shorter than a length of the magnetoresistive effect film, and a second insulating layer provided on the soft magnetic bias film; A conductor layer formed on an effect film, the second insulating layer and the conductor layer being at the same height, and a third insulating layer interposed on the second insulating layer and the conductor layer. A magnetoresistive head according to claim 1, wherein an upper shield layer is provided, and a distance between the upper shield layer and the lower shield layer is made uniform.