JPH1186234A - Magnetoresistance effect type reproduction head and magnetic disk apparatus loading the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent deterioration in pressure resistance when an insulating film between an upper and a lower magnetic shields and a magnetoresistance effect type element is thinned by constituting a magnetoresistance effect type reproduction head of a magnetic layer in which one or both of the lower magnetic shield and upper magnetic shield show a specific resistance of a specific value. SOLUTION: A magnetoresistance effect type reproduction head is constituted by layering on a substrate 11 a lower magnetic shield 12, a lower interlayer insulating film 14, a sensor part 15 of a magnetoresistance effect type element, an upper interlayer insulating film 14', an upper magnetic shield 13 and electrodes 16 at both sides of the magnetoresistance effect type element 15. In this case, one or both of the lower magnetic shield 12 and upper magnetic shield 13 use a magnetic layer of a magnetic body of a compound including at least one of Co, Fe and Ni and at least one of O, N, F, C, P, S and B. The magnetic layer has a specific resistance of not smaller than 200 μΩ.cm, preferably not smaller than 350 μΩ.cm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel magnetoresistive read head, and more particularly to a read / write separated magnetic head, a head disk assembly and a magnetic disk drive using the same.

[0002]

2. Description of the Related Art A magnetoresistive read head utilizing a magnetoresistive effect or a giant magnetoresistive effect has a magnetic multilayer film exhibiting a magnetoresistive effect or a giant magnetoresistive effect, and electrodes arranged on both sides of the magnetic multilayer film. And a shield film disposed above and below the magnetoresistive element.

The principle of magnetic field detection by a magnetoresistive element utilizes a phenomenon in which the electric resistance of a magnetic multilayer changes depending on the magnitude of a magnetic field applied to the magnetic multilayer exhibiting the magnetoresistance effect or the giant magnetoresistance effect. In this method, a change in a magnetic field is detected by flowing a current through a magnetic multilayer film and measuring a potential difference generated between both ends of the magnetic multilayer film. This is known.

In a magnetic disk drive, when a magnetic field leaking from magnetization information recorded on a magnetic disk is reproduced by using a magnetoresistive read head, the spatial resolution is increased and noise from a motor or the like which causes noise is increased. In order to reduce the magnetic field, it is also known that the upper and lower portions of the magnetoresistive element are covered with a shield film made of a magnetic material via an insulator.

With the increase in recording density of magnetic disk drives,
It is also known to reduce the gap between the upper and lower magnetic shields, that is, the gap between the magnetic gaps of the read head, in order to improve the spatial resolution. The main material used for the conventional shield film is 80Ni-Fe.
Permalloy, Fe-Al-Si sendust, Co-based amorphous magnetic material, and the like. Japanese Patent Application Laid-Open No. Hei 8-124121 discloses Ni-Fe-P alloy, Ni-Fe
It discloses that the -B alloy is formed by a plating method.

[0006]

The magnetoresistive read head has a magnetoresistive element on a lower magnetic shield via an insulating film, and an upper layer on the magnetoresistive element via an insulating film. It has a structure with a magnetic shield.

[0007] With the increase in recording density of a magnetic disk drive, particularly with the increase in linear recording density, the interval between the upper magnetic shield and the lower magnetic shield has been reduced in order to improve the spatial resolution. By reducing the thickness of the insulating film between the upper and lower magnetic shields and the magnetoresistive element or the giant magnetoresistive element (hereinafter the giant magnetoresistive element is also included in the magnetoresistive element), Withstand voltage deterioration between the upper and lower magnetic shields and the magnetoresistive element is likely to occur. It is considered that the deterioration of the breakdown voltage of the insulating film is caused by pinholes in the insulating film.

Conventionally, the resistivity of the 80Ni-Fe permalloy film used as the material of the lower and upper magnetic shield films is ρ-20 μΩ · cm, that of Fe-Al-Si sendust is ρ-80 μΩ · cm, Co-Nb-Zr Then roughly ρ
= 100 to 150 μΩ · cm. On the other hand, the average resistivity of the sensor portion of the magnetoresistive element differs depending on the configuration of the sensor portion, but is approximately ρ = 20 to 100.
It is about μΩ · cm. That is, the resistivity of the sensor part of the magnetoresistive element and the magnetic shield are almost the same,
The film thickness of the sensor part of the magnetoresistive element is approximately 5
0 nm, whereas the thickness of the magnetic shield film is 1 to 3 nm.
Since the thickness is about μm, the resistance of the magnetic shield in the same region as the sensor portion of the magnetoresistive effect element is extremely small, 1/20 or less. Therefore, when the magnetic gap interval is reduced, the step is large, such as the boundary between the sensor and the electrode of the magnetoresistive element, and the thickness of the insulating film is likely to be thin. It is considered that a current leaks to the magnetic shield, and the resistance value between the electrodes drops sharply thereby, causing dielectric breakdown of the magnetoresistive element. Even if the current leaks to the magnetic shield without destroying the element, most of the current flows because the resistance of the magnetic shield in the same area is 1/20 or less with respect to the sensor part of the magnetoresistive element as described above. It flows into the magnetic shield and cannot be reproduced by a magnetoresistive head. This problem is an unavoidable problem in the current structure of the magnetoresistive head in reducing the magnetic gap interval of the magnetoresistive head.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a magnetoresistive read head for preventing deterioration of withstand voltage due to thinning of an insulating film between an upper and lower magnetic shield and a magnetoresistive element due to a higher recording density, and a use thereof. It is another object of the present invention to provide a recording / reproducing separated magnetic head, a head disk assembly, and a magnetic disk device.

[0010]

The present invention provides a lower magnetic shield made of a magnetic material, a lower interlayer insulating film made of an insulator,
A magnetoresistive element, which consists of a magnetic material, an insulator, and an electric conductor, and detects a magnetic field by a magnetoresistance effect or a giant magnetoresistance effect, an upper interlayer insulating film made of an insulator, and an upper magnetic shield made of a magnetic material are sequentially formed on a substrate. In a magnetoresistive read head formed by deposition or a read / write separated type head in which the magnetoresistive read head and a magnetic induction type write head are formed via a magnetic shield, the read head includes the lower magnetic shield and the upper magnetic shield. It is characterized by comprising a magnetic layer having one or both specific resistances of 200 μΩ · cm or more.

According to the present invention, in the above-mentioned magnetoresistive read head, the specific resistance is 20 between at least one of the lower magnetic shield and the upper magnetic shield and the interlayer insulating film.
A magnetic layer having a thickness of 0 μΩ · cm or more is provided.

Further, according to the present invention, in the magnetoresistive read head described above, at least one of the lower interlayer insulating film and the upper interlayer insulating film has a specific resistance of at least 200 μΩ in a region covering the magnetoresistive element. -It is characterized in that a magnetic layer of not less than cm is provided.

Further, according to the present invention, in the above-mentioned magnetoresistive read head, at least one of the lower magnetic shield and the upper magnetic shield is connected to the low resistivity magnetic layer via an insulating layer and has a high specific resistance of 200 μΩ · cm or more. And a resistive magnetic layer.

The present invention relates to a magnetoresistive read head in which a lower interlayer insulating film, a magnetoresistive element for detecting a magnetic field by a magnetoresistive effect, and an upper interlayer insulating film are sequentially formed on a substrate. A magnetic layer having a specific resistance of 200 μΩ · cm or more is provided in at least one of the lower interlayer insulating layer and the upper interlayer insulating layer in a region covering the effect element.

The above-mentioned 200 μΩ · cm or more, preferably 35
The magnetic layer having a specific resistance of 0 μΩ · cm or more, more preferably 500 μΩ · cm or more contains at least one of Co, Fe, and Ni and at least one of O, N, F, C, P, S, and B. It is preferred to be made of a magnetic compound.

According to the present invention, there is provided a magnetic disk having a diameter of 3.5 inches or less, means for rotating the magnetic disk, and the above-described magnetoresistive read head and recording inductive thin film magnetic head. The magnetic disk drive is characterized in that:

In the present invention, a magnetic film having a large resistivity (200 μΩ · cm or more) is used near one or both magnetic gaps of the upper and lower magnetic shield films. If the electric resistance of the shield film is sufficiently large with respect to the electric resistance of the sensor part of the magnetoresistive element, the sense current may be reduced due to a pinhole in the insulating film between the magnetic shield and the magnetoresistive element. Even if a leak occurs in the magnetic shield, the leak current is limited and dielectric breakdown hardly occurs. Further, even if the sense current leaks to the magnetic shield and the sense current is shunted to the magnetic shield, if the leak current is reduced, the reproduction output only slightly decreases. It is desirable that the magnitude of the electric resistance of the shield film relative to the sensor part of the magnetoresistive element is approximately 10 times or more as a guide.

As a magnetic film having a high resistivity and good soft magnetic properties, a magnetic metal (Fe, Co, Ni) -metal-X
(O, F, N) based magnetic films, Ni-Fe, Fe-Co
Also, a magnetic film or the like in which C, P, S, B, etc. are added to Ni-Fe-Co or the like is known.

The present invention relates to a reproducing head utilizing the magneto-resistance effect and the giant magneto-resistance effect used in a reproducing head of a recording / reproducing separated thin film magnetic head used in a magnetic disk device or the like, in which at least an upper and lower magnetic shields are used. When a magnetic gap having a high resistivity is used for at least a part of the magnetic head, the magnetoresistive effect element and the upper or lower magnetic shield are formed when the magnetic gap interval of the read head, which is determined by the upper and lower magnetic shield intervals, is reduced. Even if a sense current leaks between them, reproduction is possible. By using a magnetoresistive read head having a narrow magnetic gap interval according to the present invention, a linear recording density is high and an interval between the magnetic head and the recording head can be narrowed. Is obtained.

According to the present invention, a magnetic disk for recording information, an inductive recording head for writing the information on the magnetic disk, and a magnetoresistive read head for reproducing the information written on the magnetic disk are integrally formed. In a head disk assembly including the formed recording / reproducing separation type thin film magnetic head and driving means for rotating the disk, the recording / reproducing separation type thin film magnetic head is as described above, and is 10 Gbit / in. ^It has a recording density of ² or more.

According to the present invention, a magnetic disk for recording information, an inductive recording head for writing the information on the magnetic disk, and a magnetoresistive reproducing head for reproducing the information written on the magnetic disk are integrally formed. A magnetic disk drive comprising a plurality of head disk assemblies each having a formed recording / reproducing separation type thin film magnetic head and driving means for rotating the disk, wherein the magnetic disk drive comprises the head disk assembly described above. Features.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) FIG. 1 is a view showing a medium facing surface of an embodiment of a magnetoresistive read head according to the present invention. The laminated structure of the magnetoresistive read head shown in FIG.
A lower magnetic shield 12, a lower interlayer insulating film 14, a sensor part 15 of a magnetoresistive element, and an upper interlayer insulating film 1
4 ', the upper magnetic shield 13 and the electrodes 16 provided on both sides of the sensor portion 15 of the magnetoresistive element are stacked in this embodiment, and the material of the lower magnetic shield 12 and the upper magnetic shield 13 is resistivity. ρ ~ 1600
Fe-Si-O of 0 μΩ · cm was used. The film thickness of the lower and upper magnetic shield films was 1.6 μm, and the magnetic gap interval was 0.18 μm. As the magnetoresistive element, a magnetoresistive read transducer having a hard magnetic bias film described later was used. The configuration of the sensor portion 15 of the magnetoresistive element has a laminated structure of a magnetic material, an insulator, and an electric conductor from the top.
m / bias film 20 nm, so that the lower interlayer insulating film 14 on the lower magnetic shield has a thickness of 50 nm and the upper interlayer insulating film 14 on the magnetoresistive element so that the magnetoresistive film is at the center of the magnetic gap. 'Was 80 nm thick. Since the average specific resistance of the sensor portion of the magnetoresistive element used in this embodiment is ρ to 50 μΩ · cm, the length and width of the sensor are both 1 μm, and the film thickness is 50 nm, the resistance value of the sensor portion is 10Ω. Since the specific resistance of the magnetic shield film is ρ to 16000 μΩ · cm and the film thickness is 1.6 μm, the resistance value of the magnetic shield in the sensor region is 10 μm.
It becomes 0Ω. That is, the resistance value between the electrodes is changed from 10Ω to 9.1Ω by the sense current leaking to the magnetic shield.
Therefore, even if the sense current leaks to the magnetic shield, the sensor part 15 of the magnetoresistive element does not change.
Does not break. Further, since the current flowing through the sensor portion 15 of the magnetoresistive element is reduced by about 9%, the output becomes 17%.
It is possible to reproduce only by decreasing about%. The above estimate is an estimate for a case where the insulating film between the magnetic shield and the sensor portion 15 of the magnetoresistive element is short-circuited due to a pinhole or the like. Since the amount of current is smaller than the above estimate, the amount of decrease in the reproduction output is generally less than the above estimate. In addition, the estimation of the resistance value of the magnetic shield part was performed for the sensor area of the magnetoresistive element, but in general, the thickness of the insulating film was increased in areas other than the vicinity of the sensor of the magnetoresistive element, and the sense current was large. There is almost no possibility of leaking into the magnetic shield, so this is a sufficiently valid model. In this embodiment, the lower and upper magnetic shields (12 and 13) are set to have a resistivity ρ to
Although it was made only of a Fe-Si-O film of 16000 μΩ · cm, it may be a magnetic multilayer film in which high-resistance magnetic films and insulating films are alternately laminated.

The magnetoresistive element (MR) according to this embodiment
FIG. 2 shows a conceptual diagram of the element). The MR element comprises a sensor portion (MR layer) 15 of a magnetoresistive element and an electrode 16 including a hard magnetic bias layer for generating a longitudinal bias in the film. Electrode 1 including hard magnetic bias layer
Numeral 6 has electrical and magnetic continuity with the MR sensor 15. The hard magnetic bias film of the electrode 16 including the hard magnetic bias layer includes CoCr, CoPt, and CoCr.
Although a single layer such as Pt can be provided, it is desirable to use a lower or upper layer of tungsten, gold, chromium, or the like. The thickness of the hard magnetic bias film is selected to provide a desired amount of bias flux. Also, the lateral bias is necessary for the MR sensor 15,
The bias may be formed by a soft film bias, a branch bias, a spiral bias, or any other compatible lateral bias.

FIG. 3 is a perspective view of a magnetic head (MR sensor) using a spin valve magnetoresistive film having another structure of the present invention.

The MR sensor of the present invention includes a first soft ferromagnetic material on a suitable substrate 31 such as glass or ceramic.
The structure has a magnetic layer 32, a non-magnetic metal layer 1, and a ferromagnetic second magnetic layer 2 attached thereto. The ferromagnetic layers 32 and 2
When no magnetic field is applied, each magnetization direction is about 9
The angle difference should be 0 degrees. Further, the second magnetic layer 2
Is fixed in the same direction as the direction of the magnetic field of the magnetic medium. The magnetization direction of the soft magnetic ferromagnetic first magnetic layer 32 when no magnetic field is applied is inclined by 90 degrees with respect to the magnetic field direction of the second magnetic layer. In response to the applied magnetic field, magnetization rotation occurs in the first magnetic layer 32 and changes. 8 is an electrode.

For the first magnetic layer 32, means for generating a bias in the vertical direction for maintaining a single domain state in a direction parallel to the paper surface is used. As means for generating a bias in the vertical direction, a hard ferromagnetic layer 7 having a high coercive force, a high squareness, and a high electric resistance is used. The hard ferromagnetic layer 7 is in contact with an end region of the soft magnetic ferromagnetic first magnetic layer 32. The magnetization direction of the hard ferromagnetic layer 7 is parallel to the paper surface.

The antiferromagnetic layer can be deposited in contact with the end regions of the first magnetic layer 32, producing the necessary vertical bias. These antiferromagnetic layers preferably have a blocking temperature which is sufficiently different from that of the antiferromagnetic layer 3 used to fix the magnetization direction of the ferromagnetic second magnetic layer 2.

(Embodiment 2) FIG. 4 is a view showing a medium facing surface of another embodiment of a magnetoresistive read head according to the present invention. In this embodiment, the lower magnetic shield 12 and the upper magnetic shield 13 are made of 46Ni-F formed by plating.
a low-resistance lower magnetic shield 122 and a low-resistance upper magnetic shield 132 made of an e-film (.rho.-45 .mu..OMEGA.cm, film thickness 1.5 .mu.m), and an Fe-Ni-O ferrite film formed on the magnetoresistive element side by plating. (Ρ ~ 1Ω · cm, 0.5
μm) in a laminated structure in which a high-resistance lower magnetic shield 121 and a high-resistance upper magnetic shield 131 are arranged. A giant magnetoresistive spin-valve film is used for the sensor portion 15 of the magnetoresistive element.
5nm / CrMnPt30nm / CoFe3nm / Cu
2 nm / CoFe 1 nm / NiFe 5 nm / Ta 5 nm
And The free layer of the spin valve film of this embodiment is CoFe
/ NiFe layer, the lower interlayer insulating film 14 on the lower magnetic shield has a thickness of 85 nm, and the upper interlayer insulating film 1 on the magnetoresistive effect element, so that it is at the center of the magnetic gap.
The film thickness of 4 'was 50 nm. That is, the magnetic gap interval is
0.186 μm. Ferrite-based materials such as Fe-Ni-O used in this example have sufficiently high resistivity,
Dielectric breakdown of the magnetoresistive element is unlikely to occur. By optimizing the high-resistance shield film (high resistivity, thinning, improvement of soft magnetic characteristics, etc.), the thickness of the insulating film between the upper and lower magnetic shields and the magnetoresistive element can be reduced to almost zero. It is possible. In the case where the spin-valve giant magnetoresistive film used in this embodiment is used as an example, the thickness of the insulating film on the lower magnetic shield is 35 nm, and the thickness of the insulating film on the magnetoresistive element is zero. That is, the magnetic gap interval is set to 86n.
m. One or both of the high-resistance lower magnetic shield 121, the high-resistance upper magnetic shield 131, the low-resistance lower magnetic shield 122, and the low-resistance upper magnetic shield 132 are magnetic multilayers in which a magnetic film and an insulating film are alternately laminated. It may be a film.

(Embodiment 3) FIG. 5 is a view showing another embodiment of a magnetoresistive read head according to the present invention. FIG.
(A) is a view showing the medium facing surface, and (b) is a view of the high resistance upper magnetic shield 131 (region surrounded by a dotted line), the sensor portion 15 of the magnetoresistive element, and the electrode 16 as viewed from above. is there. In this embodiment, the high-resistance upper magnetic shield 13
The distance between 1 and the high-resistance lower magnetic shield 121 is 0.146.
μm. The method of manufacturing the magnetoresistive read head of the present embodiment is as follows. A 46-Ni-Fe film is deposited on the substrate 11 to a thickness of 2 μm, shaped into a lower magnetic shield shape, and then plated with a Fe-Ni-O ferrite film (ρ to 1Ω).・ Cm)
After 5μm deposition, a mask to cover the region for forming the sensor of the magnetoresistive effect element, the Al ₂ O ₃ 0.5
After the μm deposition, Al ₂ O ₃ deposited on the mask was removed together with the mask. After that, Al ₂ O ₃ was further deposited to a thickness of 65 nm, and then a spin-valve magnetoresistive element 15 and an electrode 16 were formed as in the second embodiment. Then Al ₂ O ₃
Is deposited on the mask after depositing a 30-nm thick Fe-Ni-O-plated ferrite film at a thickness of 0.5 μm and covering the sensor portion of the magnetoresistive element, and depositing Al ₂ O ₃ at a thickness of 0.5 μm. Removed Al ₂ O ₃ together with the mask,
A 46 Ni-Fe film was deposited at 2 μm and shaped into an upper magnetic shield shape. Ferrite-based materials such as Fe-Ni-O used in the present embodiment have sufficiently high resistivity, so that dielectric breakdown of the magnetoresistive element is unlikely to occur. Further, by optimizing the high resistance shield film, it is possible to make the thickness of the insulating film between the upper and lower magnetic shields and the magnetoresistive element almost zero. The high-resistance lower magnetic shield 121, the high-resistance upper magnetic shield 131, the low-resistance lower magnetic shield 122, and the low-resistance upper magnetic shield 1
Either one or both of them may be a magnetic multilayer film in which magnetic films and insulating films are alternately laminated.

(Embodiment 4) FIG. 6 is a diagram showing a medium facing surface of another embodiment of a magnetoresistive read head according to the present invention. In this embodiment, the interlayer insulating film (123 and 133) comprising comprising a lower magnetic shield 12 and the upper magnetic shield 13 from 80Ni-Fe permalloy low resistance magnetic shield (122, 132) from the Al ₂ O _3, Fe-Hf- O
(Ρ ~ 2000μΩcm) High-resistance magnetic shield (1
21 and 131). The thicknesses of the magnetic films of the lower and upper magnetic shield films were 2 μm, and the magnetic gap interval was 0.18 μm. The structure of the upper magnetic shield film is 80 Ni-Fe 1.8 μm / Al ₂ O ₃ 50 nm /
Fe-Hf-O 0.2 μm, and the lower magnetic shield is the opposite. The configuration of the magnetoresistive element used in this embodiment is the same as that of the first embodiment. The resistance of the sensor portion is 10Ω, and the resistivity of the high-resistance magnetic shield film is ρ to 20.
Since the resistance value of the magnetic shield in the sensor area is 100Ω, which is sufficiently larger than the resistance value of the sensor part, the output slightly decreases even if a current leaks to the magnetic shield, because the resistance value of the magnetic shield is 100 μΩ · cm and the film thickness is 0.2 μm. It is possible to play just by doing. The high-resistance magnetic shields (121 and 131) and the low-resistance magnetic shield (122)
And 132) may be a magnetic multilayer film in which magnetic films and insulating films are alternately stacked.

(Embodiment 5) FIG. 7 is a view showing another embodiment of a magnetoresistive read head according to the present invention. FIG.
(A) is a view showing the medium facing surface, and (b) is a view of the high resistance upper magnetic shield 131 (region surrounded by a dotted line), the sensor portion 15 of the magnetoresistive element, and the electrode 16 as viewed from above. is there. In this embodiment, the high-resistance upper magnetic shield 13
The distance between 1 and the high-resistance lower magnetic shield 121 is 0.14 μ.
m. In the method of manufacturing the magnetoresistive read head of this embodiment, an 80Ni—Fe film of a conventional material is deposited on the substrate 11 by 2 μm, shaped into a lower magnetic shield shape, and
₂ O ₃ is deposited to a thickness of 30 nm, and Co—Fe—B—Si—O (ρ to
500μΩ · cm) after the 50nm deposit, a mask to cover the region for forming the sensor part of the magnetoresistive element, after 50nm deposited Al ₂ O _3, the Al ₂ O ₃ deposited on the mask mask Was removed. After that, further Al ₂ O ₃
Was deposited to form a magnetoresistive element 15 and an electrode 16. After that, Al ₂ O ₃ is deposited to a thickness of 60 nm,
After depositing 50 nm of Co-Fe-B-Si-O, a mask is formed so as to cover the sensor part of the magnetoresistive element,
After depositing Al ₂ O ₃ by 50 nm, the Al deposited on the mask was
_After removing ₂ O ₃ together with the mask and further depositing Al ₂ O ₃ to a thickness of 30 nm, an 80 Ni—Fe film was deposited at 2 μm and shaped into an upper magnetic shield shape. The resistance value of the sensor portion of the magnetoresistive element used in this embodiment is 10Ω, the resistivity of the high resistance shield film is ρ to 500 μΩ · cm, and the film thickness is 50 nm.
Therefore, the resistance value of the high resistance shield film in the sensor area is 100Ω, which is sufficiently large compared to the resistance value of the sensor part. Even if current leaks to the shield, it is possible to reproduce with only a slight decrease in output. is there. One or both of the high resistance magnetic shields (121 and 131) and the low resistance magnetic shields (122 and 132) may be a magnetic multilayer film in which magnetic films and insulating films are alternately laminated.

(Embodiment 6) In each of Embodiments 1 to 5, the upper magnetic shield 13 and the lower magnetic shield 12 have the same configuration. For example, 80Ni-Fe which has been conventionally used as the lower magnetic shield film is used. Permalloy film, Fe-A
Using a l-Si sendust film or a Co-based amorphous magnetic film, or a magnetic multilayer film in which those magnetic materials and insulators are alternately stacked, using a magnetic material having a high resistivity only in the upper magnetic shield film, The lower magnetic shield has a laminated structure of a conventional material, an insulating material and a high-resistance magnetic material as shown in FIG. 6, and the upper magnetic shield is a portion covering the magneto-resistance effect film with the high-resistance magnetic material as shown in FIG. It is also possible to use them in combination, such as to use them only. In the above embodiment, Al ₂ O ₃ was used as the insulating film, SiO ₂
Oxide or nitride such as SiN may be used. As described in the second and third embodiments, by optimizing the configuration of the sensor section of the magnetoresistive element and the high-resistance magnetic shield film, etc., the distance between the upper magnetic shield and the magnetoresistive element and the magnetoresistive element can be improved. Either one or both of the insulating films between the effect type element and the lower magnetic shield can be made zero in any of the above embodiments.

In each of the first to fifth embodiments, the MR element shown in FIG. 2, the spin valve type magnetoresistive element shown in FIG. 3, or the giant magnetoresistive element is used as the magnetoresistive element. It may be used for any of an element and a tunnel type magnetoresistive element.

(Embodiment 7) FIG. 8 is a schematic diagram of a hard disk drive using the magnetoresistive read head and the spin valve magnetoresistive read head described in Examples 1 to 6. This apparatus has a disk rotation shaft 164 and a spin valve motor 165 for rotating the disk at a high speed. One or more (two in this embodiment) disks 167 are provided at a predetermined interval on the disk rotation shaft 164. Installed. Therefore, each magnetic disk 167 rotates integrally with the disk rotation shaft 164. The magnetic disk 167 is a disk having a predetermined radius and thickness, and has a permanent magnet film formed on both surfaces, and serves as a data recording surface.
This apparatus also has a rotary shaft 162 for positioning the head and a voice coil motor 163 for driving the rotary shaft 162 outside the magnetic disk 167. A plurality of access arms 161 are attached to the rotary shaft 162 for positioning the head. At the end of each access arm 161, a recording / reproducing head (hereinafter referred to as a head) 160 is attached. Therefore, each head 160 moves in a radial direction on each magnetic disk 167 by rotating the positioning rotary shaft 162 by a predetermined angle, and is positioned at a predetermined position. Each head 160 is mounted on the disk 1
Due to the balance between the buoyancy generated when the 67 rotates at a high speed and the pressing force of a gimbal which is an elastic body constituting a part of the access arm 161, the space is maintained at a distance of about several tens nm from the surface of the disk 167. The spindle motor 165 and the voice coil motor 163 are respectively connected to a hard disk controller 166, and the rotation speed of the disk 167 and the position of the head 160 are controlled by the hard disk controller 166.

FIG. 9 is a sectional view of an inductive recording head used in the hard disk drive of the present invention. This thin-film head is composed of an upper magnetic shield 186, a lower magnetic film 184 made of a magnetic film attached thereon, and an upper magnetic shield 186. Magnetic film 1
Consists of 85. A non-magnetic insulator 189 is attached between these magnetic films. Part of the insulator is a magnetic gap 18
8 is specified. The support is an air bearing surface (AB
S) in the form of a slider, which is in close proximity to the rotating media of the disk during disk file operations.

The thin film magnetic head has a back gap 190 formed by the upper magnetic film 185 and the lower magnetic film 184. The back gap 190 has an intervening coil 187
Are separated from the magnetic gap.

The continuous coil 187 is a layer formed on the lower magnetic film 184 by, for example, plating.
These are electromagnetically coupled. The coil 187 has an electrical contact at the center of the coil buried with insulator 189, and also has a larger area at the outer end of the coil as an electrical contact. The contacts are connected to an external electric wire and a read / write signal processing head circuit (not shown).

In the present invention, the coil 187 made of a single layer has a slightly distorted elliptical shape, and a portion having a small cross-sectional area is arranged closest to the magnetic gap, and the distance from the magnetic gap is increased. Becomes larger, the cross-sectional area gradually increases.

However, the elliptical coil has a back gap of 1
The coils are relatively densely packed between 90 and the magnetic gap 188, and the width or cross-sectional diameter of the coil is small in this area. Further, a large cross-section reduction at the portion farthest from the magnetic gap results in a decrease in electrical resistance. In addition, elliptical (elliptical) coils have no corners, sharp corners or edges, and have less resistance to current. In addition, the elliptical shape requires a smaller total length of the conductor than a rectangular or circular (annular) coil. As a result of these advantages, the total resistance of the coil is relatively low, the heat generation is low, and a suitable heat dissipation is obtained. Since the heat is reduced by a considerable amount, the collapse, extension and expansion of the thin film layer are prevented, and the ball
The cause of tip protrusion is eliminated.

An elliptical coil shape in which the change in width progresses almost uniformly can be attached by a conventional plating technique which is less expensive than sputtering or vapor deposition. A coil having another shape, particularly a cornered shape, tends to have a structure in which the plating adhesion is uneven. The removal of corners and sharp edges places less mechanical stress on the resulting coil.

In this embodiment, a coil wound in a large number of turns is formed in a substantially elliptical shape between the magnetic cores, the cross-sectional diameter of the coil gradually increases from the magnetic gap toward the back gap, the signal output increases, and heat is generated. Decrease.

FIG. 10 is a perspective conceptual view of a magnetic head having an inductive recording head and a magneto-resistance effect reproducing head according to the present invention. Substrate 15 doubles as head slider
0, a lower magnetic shield 182, a magnetoresistive film 11
0, a magnetic domain control film 141, a read head having an electrode terminal 140, and a lower magnetic film and an upper magnetic film 183 which also serve as an upper magnetic shield 186. A lower gap and an upper gap are not shown. An inductive recording head in which a magnetomotive force is generated in an upper magnetic core and an upper shield / lower core by an electromagnetic induction effect is mounted.

FIG. 11 is a perspective view of the negative pressure slider. The negative pressure slider 170 has a negative pressure generating surface 178 surrounded by an air introducing surface 171 and two positive pressure generating surfaces 177, 177 for generating a levitation force, and further has an air introducing surface 179 and two positive pressure generating surfaces. Groove 17 having a larger step than negative pressure generating surface 178 at the boundary between surfaces 177, 177 and negative pressure generating surface 178.
And 4. The air outflow end 175 has a recording / reproducing separation type thin-film magnetic head element 176 having an inductive recording head for recording information on the magnetic disk, which will be described later, and an MR sensor for reproducing.

When the negative pressure slider 170 flies,
The air introduced from the air introduction surface 179 is the negative pressure generation surface 17.
8, the air flow toward the groove 174 is also created at that time, so that the air introduction surface 17 is also provided inside the groove 174.
There is an air flow from 9 to the air outflow end 175. Therefore, even if the dust floating in the air when the negative pressure slider 170 flies is introduced from the air introduction surface 171, it is introduced into the groove 174, is swept away by the flow of air in the groove 174, and flows out of the air outflow end 178. This is discharged to the outside of the negative pressure slider 170. Further, when the negative pressure slider 170 flies, since the air flow always exists inside the groove 4 and there is no stagnation or the like, dust does not aggregate.

FIG. 12 is an overall perspective view of a magnetic disk drive which is an example of the present invention. The configuration of the magnetic disk device includes a magnetic disk for recording information, a DC motor (not shown) for rotating the magnetic disk, a magnetic head for writing and reading information, and a magnetic head for supporting the magnetic disk. Positioning means for changing the position by means of
It consists of an actuator and a voice coil motor. These figures show examples in which five magnetic disks are mounted on the same rotating shaft to increase the total storage capacity.

According to this embodiment, it is possible to sufficiently record even on a high coercive force medium even in a high frequency region, and a medium transfer speed of 15 MB / sec or more, a recording frequency of 45 MHz or more,
A magnetic disk device with an areal recording density of 10 Gb / in ² or more because a high-sensitivity MR sensor having an excellent MR effect such as high-speed transfer of data of 4000 rpm or more, reduction of access time, and increase of recording capacity can be obtained. Is obtained.

[0047]

According to the present invention, when the magnetic gap interval of the reproducing head determined by the upper and lower magnetic shield intervals is reduced, the insulator between the upper and lower magnetic shields and the magnetoresistive element is reduced. Even if the sense current is shunted to the magnetic shield due to the withstand voltage failure, the resistance of the magnetic shield is high and the shunt of the sense current is limited, so that the withstand voltage degradation in which the dielectric breakdown of the magnetoresistive element does not easily occur is prevented. Further, even if the sense current is diverted to the magnetic shield, it is possible to provide a magnetoresistive effect type reproducing head capable of reproducing only by slightly reducing the reproducing output. Further, by using the magnetoresistive read head having a narrow magnetic gap interval according to the present invention, the linear recording density is high and the interval between the magnetic head and the recording head can be narrowed. A disk assembly and a magnetic disk drive using the same can be provided.

[Brief description of the drawings]

FIG. 1 is a sectional view of a medium facing surface of a magnetoresistive read head according to an embodiment of the present invention.

FIG. 2 is a sectional view of a magnetoresistive element.

FIG. 3 is a perspective view of a spin-valve magnetoresistive read head according to another embodiment of the present invention.

FIG. 4 is a cross-sectional view of a medium facing surface of a magnetoresistive read head according to another embodiment of the present invention.

FIG. 5 is a cross-sectional view of a medium facing surface of a magnetoresistive read head according to another embodiment of the present invention, and a plan view of a magnetoresistive element and a high-resistance upper magnetic shield as viewed from above.

FIG. 6 is a sectional view of a medium facing surface of a magnetoresistive read head according to another embodiment of the present invention.

FIG. 7 is a cross-sectional view of a medium facing surface of a magnetoresistive read head according to another embodiment of the present invention, and a plan view of a magnetoresistive element and a high-resistance upper magnetic shield as viewed from above.

FIG. 8 is a schematic diagram of a hard disk device.

FIG. 9 is a sectional view of an inductive recording head.

FIG. 10 is a partial cross-sectional perspective view of a read / write separated magnetic head.

FIG. 11 is a perspective view of a negative pressure slider.

FIG. 12 is an overall perspective view of a magnetic disk drive.

[Explanation of symbols]

11, 31 ... substrate, 12, 182 ... lower magnetic shield,
13, 186: Upper magnetic shield, 14, 123: Lower interlayer insulating film, 14 ', 133: Upper interlayer insulating film, 15:
Sensor part of magnetoresistive element, 16 electrodes, 12
DESCRIPTION OF SYMBOLS 1 ... High resistance lower magnetic shield, 122 ... Low resistance lower magnetic shield, 131 ... High resistance upper magnetic shield, 132 ...
Low resistance upper magnetic shield, 142, 187 ... coil, 1
67: magnetic disk, 185: upper magnetic film, 188: magnetic gap.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Katsuro Watanabe, Inventor 1-280 Higashi Koikekubo, Kokubunji-shi, Tokyo Inside the Central Research Laboratory, Hitachi, Ltd. Central Research Laboratory (72) Inventor, Moriaki Fuyama 1-280 Higashi Koikebo, Kokubunji-shi, Tokyo Inside Central Research Laboratory, Hitachi, Ltd.

Claims (17)

[Claims] A lower magnetic shield made of a magnetic material, a lower interlayer insulating film, a magnetoresistive element for detecting a magnetic field by a magnetoresistance effect, an upper interlayer insulating film, and an upper magnetic shield made of a magnetic material are sequentially formed on a substrate. In the magnetoresistive read head, the specific resistance of at least one of the lower magnetic shield and the upper magnetic shield is 200 μΩcm.
A magnetoresistive effect type reproducing head characterized by the above. 2. A lower magnetic shield made of a magnetic material, a lower interlayer insulating film, a magnetoresistive element for detecting a magnetic field by a magnetoresistance effect, an upper interlayer insulating film, and an upper magnetic shield made of a magnetic material are sequentially formed on a substrate. Wherein the magnetic layer having a specific resistance of not less than 200 μΩ · cm is provided between at least one of the lower magnetic shield and the upper magnetic shield and the interlayer insulating film. Magnetoresistive read head. 3. A lower magnetic shield made of a magnetic material, a lower interlayer insulating film, a magnetoresistive element for detecting a magnetic field by a magnetoresistance effect, an upper interlayer insulating film, and an upper magnetic shield made of a magnetic material are sequentially formed on a substrate. In the magnetoresistive read head, a magnetic layer having a specific resistance of at least 200 μΩcm is provided in at least one of the lower interlayer insulating film and the upper interlayer insulating film in a region covering at least the magnetoresistive element. A magnetoresistive read head characterized in that it is provided. 4. A lower magnetic shield made of a magnetic material, a lower interlayer insulating film, a magnetoresistive element for detecting a magnetic field by a magnetoresistance effect, an upper interlayer insulating film, and an upper magnetic shield made of a magnetic material are sequentially formed on a substrate. Wherein at least one of the lower magnetic shield and the upper magnetic shield comprises a low-resistivity magnetic layer and a high-resistivity magnetic layer of 200 μΩ · cm or more via an insulating layer. Magnetoresistive read head. 5. A magnetoresistive read head in which a lower interlayer insulating film, a magnetoresistive element for detecting a magnetic field by a magnetoresistive effect, and an upper interlayer insulating film are sequentially formed on a substrate. A magnetoresistive effect type, wherein a magnetic layer having a specific resistance of 200 μΩ · cm or more is provided in at least one of the lower interlayer insulating layer and the upper interlayer insulating layer in a region covering the element. Playhead. 6. The magnetic layer having a specific resistance of 200 μΩ · cm or more, wherein at least one of Co, Fe and Ni and O,
6. The magnetoresistive read head according to claim 1, comprising a compound magnetic material containing at least one of N, F, C, P, S, and B. 7. A read / write separated magnetic head in which a magnetoresistive read head and a magnetic induction type write head are formed via a magnetic shield, wherein the read head is a lower magnetic shield made of a magnetic material, and a lower interlayer insulating layer. A magnetoresistive read head in which a film, a magnetoresistive element for detecting a magnetic field by a magnetoresistive effect, and an upper magnetic shield comprising an upper interlayer insulating film and a magnetic material are sequentially formed on a substrate;
A read / write separated magnetic head comprising a magnetic layer having a specific resistance of at least one of the lower magnetic shield and the upper magnetic shield of 200 μΩ · cm or more. 8. A read / write separated magnetic head in which a magnetoresistive read head and a magnetic induction type write head are formed via a magnetic shield, wherein the read head is a lower magnetic shield made of a magnetic material, and a lower interlayer insulating layer. A magnetoresistive read head in which a film, a magnetoresistive element for detecting a magnetic field by a magnetoresistive effect, and an upper magnetic shield comprising an upper interlayer insulating film and a magnetic material are sequentially formed on a substrate;
A read / write separated magnetic head, wherein a magnetic layer having a specific resistance of 200 μΩ · cm or more is provided between at least one of the lower magnetic shield and the upper magnetic shield and the interlayer insulating film. 9. A read / write separation type magnetic head in which a magnetoresistive read head and a magnetic induction type write head are formed via a magnetic shield, wherein the read head is a lower magnetic shield made of a magnetic material, and a lower interlayer insulating layer. A lower magnetoresistive read head in which a film, a magnetoresistive element for detecting a magnetic field by a magnetoresistive effect, an upper interlayer insulating film, and an upper magnetic shield made of a magnetic material are sequentially formed on a substrate; And a magnetic layer having a specific resistance of at least 200 μΩ · cm in at least one of the upper interlayer insulating film and a region covering the magnetoresistive element. . 10. A read / write separation type magnetic head in which a magnetoresistive read head and a magnetic induction type write head are formed via a magnetic shield, wherein the read head is a lower magnetic shield made of a magnetic material, and a lower interlayer insulating layer. A magnetoresistive read head in which a film, a magnetoresistive element for detecting a magnetic field by a magnetoresistive effect, an upper interlayer insulating film, and an upper magnetic shield made of a magnetic material are sequentially formed on a substrate;
At least one of the lower magnetic shield and the upper magnetic shield is connected to the low-resistivity magnetic layer through an insulating layer by 200 μΩ ·
A recording / reproducing separation type magnetic head comprising a high resistivity magnetic layer having a diameter of at least cm. 11. A read / write separated magnetic head in which a magnetoresistive read head and a magnetic induction type write head are formed via a magnetic shield, wherein the read head generates a magnetic field by a lower interlayer insulating film and a magnetoresistive effect. A magnetoresistive element to be detected, and a magnetoresistive read head in which an upper interlayer insulating film is sequentially formed on a substrate, and the lower interlayer insulating layer and the upper interlayer insulating layer are provided at least in a region covering the magnetoresistive element. A recording / reproducing separation type magnetic head, wherein a magnetic layer having a specific resistance of 200 μΩ · cm or more is provided in at least one of the interlayer insulating layers. 12. The magnetic layer having a specific resistance of 200 μΩ · cm or more, wherein the magnetic layer contains at least one of Co, Fe and Ni and at least one of O, N, F, C, P, S and B. The recording / reproducing separation type magnetic head according to any one of claims 7 to 11, comprising a body. 13. A magnetic disk having a diameter of 3.5 inches or less, and means for rotating the magnetic disk,
A magnetic disk drive comprising the magnetoresistive read head and the inductive thin film magnetic head for recording according to any one of the above. 14. A magnetic disk having a diameter of 3.5 inches or less, and means for rotating the magnetic disk,
3. A magnetic disk drive comprising the read / write separated magnetic head according to any one of 2. 15. A magnetic disk for recording information, an inductive recording head for writing the information on the magnetic disk, and a magnetoresistive read head for reproducing the information written on the magnetic disk are integrally formed. 7. A thin-film magnetic head according to claim 1, wherein said magneto-resistive read head is provided with a read / write separated thin-film magnetic head and driving means for rotating said disk. Consisting of 3Gbit / in ²
A head disk assembly having the above recording density. 16. A magnetic disk for recording information, an inductive recording head for writing the information on the magnetic disk, and a magnetoresistive read head for reproducing the information written on the magnetic disk are integrally formed. 2. A head disk assembly comprising a read / write separation type thin-film magnetic head and a drive unit for rotating the disk, wherein the read / write separation type thin-film magnetic head is provided.
2. The thin-film magnetic head according to any one of 2.
A head disk assembly having a recording density of t / in ² or more. 17. A magnetic disk for recording information, an inductive recording head for writing the information on the magnetic disk, and a magnetoresistive read head for reproducing the information written on the magnetic disk are integrally formed. 16. A magnetic disk drive comprising a plurality of head-disk assemblies each comprising a read / write separated thin-film magnetic head and driving means for rotating said disk.
A magnetic disk drive comprising the head disk assembly according to claim 1.