JP2000076629A - Magnetoresistive effect type head, its manufacture and magnetic storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetoresistive effect type head ('MRE head') capable of a high output corresponding to a narrow track width, to provide a manufacturing method by which the MRE head can be manufactured easily and surely, and to provide a magnetic storage device capable of recording and reproducing in excess of 20 giga bit/(square) inch in surface recording density by means of the MRE head. SOLUTION: The MRE head is arranged such that an effective reproducing track width is 0.5 μm or less and that a distance between a pair of permanent magnet films 23, which applies bias to a magnet sensing area 100, is made longer by 0.3 μm or more than a distance between a pair of electrode films 24 for feeding an electric current. The permanent magnet films 23 and the electrode films 24 are formed by the ion beam sputter method using a separate photo mask. The recording and reproducing head is designed to use such MRE head.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetoresistive head capable of reproducing magnetization recorded on a magnetic medium with a narrow width of 0.1 .mu.m to 0.5 .mu.m, a method of manufacturing the same, and a magnetic storage device.

[0002]

2. Description of the Related Art With the increase in capacity of magnetic recording devices, Ni
A magnetoresistive head (hereinafter, referred to as an AMR head) utilizing the anisotropic magnetoresistance effect of an Fe film has been put to practical use. Regarding this AMR head, “IEEE Tra
ns. On Magn, MAG7 (1971) 150 "
In "A Magnetoresistivity"
Read Out Transducer ".

In recent years, in response to the improvement in magnetic recording density, A
A GMR head using a giant magnetoresistive effect (hereinafter, referred to as GMR) capable of achieving a much higher output than an MR head has attracted attention. In this GMR, in particular, the magnetoresistive effect generally called a spin valve effect, in which the change in resistance corresponds to the cosine between the magnetization directions of two adjacent magnetic layers, means that a large change in resistance occurs with a small operating magnetic field. From
It is expected as the next generation GMR head of the AMR head.

FIG. 7 shows a laminated structure of this spin valve element. The spin-valve laminated film 10 includes the first ferromagnetic layer 1
1, nonmagnetic layer 12, second ferromagnetic layer 13, antiferromagnetic layer 14
Are stacked in this order. In the spin valve laminated film 10, the magnetization of the second ferromagnetic layer 13 is
, And a uniaxial anisotropy is given in a direction perpendicular to the track width direction (direction 16 in the figure). On the other hand, the first ferromagnetic layer 11 is a non-pinned magnetization rotating layer, and the magnetization is parallel to the track width direction (the direction of 15 in the figure) and perpendicular to the second ferromagnetic layer 13. A magnetic field leaking from the magnetic medium can be detected by a resistance change corresponding to a cosine between the magnetization directions of the first and second ferromagnetic layers.

A GMR head using the spin valve effect is described in IEEE Trans. On Mag.
n,. Vol. 30, no. 6 (1994) 3801 "
"Design, Fabrication &
Testing of Spin Valve Rea
d Heads for High DensityR
and "ecoding".

FIG. 8 shows an example of a recording / reproducing head using this spin valve element. This recording / reproducing head includes a lower shield layer 21 on a ceramic base 20 serving as a slider.
The lower gap layer 22 is sequentially stacked, and the track width spin valve layer 10 is formed thereon. A permanent magnet film 23 for applying a bias magnetic field to the magnetization rotation layer 11 of the spin valve layer 10 to form a single magnetic domain is formed on both ends in the track width direction of the spin valve layer 10. An electrode film 24 for supplying a current to the electrode 10 is formed. The laminated film of the permanent magnet film 23 and the electrode film 24 has a structure in which the spin valve layer 10 is sandwiched at both ends in the track width direction. On these, an upper gap layer 25 and an upper shield layer 2 which is also used as a recording magnetic pole.
6. A recording magnetic pole 28 is formed via a recording gap layer 27. Further, a protective layer 29 covering them is provided. Between the recording magnetic poles 26 and 27, an exciting coil (not shown) insulated by a photoresist in the depth direction of the drawing is provided.

In the above-described AMR head and GMR head, it is indispensable to make the magnetic layer 11 whose magnetization changes according to the medium magnetic field into a single magnetic domain in order to suppress Barkhausen noise. An element structure for realizing this is described in Japanese Patent Publication No. 3-125311. This element structure will be described with reference to FIG.

In FIG. 9, it is assumed that a spin valve layer is used in a magneto-sensitive region where the medium magnetic field is detected.
(A) shows the layer configuration when the element is viewed from the medium facing surface. The permanent magnet film 2 serves as an end region for supplying a bias magnetic field and a sense current to the magneto-sensitive region 100 which is a spin valve layer.
3 and an electrode film 24 are formed. The permanent magnet film 24 is joined to the first ferromagnetic layer 11 of the spin valve film 10. (B) shows the state of magnetization of the first ferromagnetic layer 11 that changes with respect to an external magnetic field in the spin valve film when there is no medium magnetic field, and the state of the permanent magnet film 23 that biases the first ferromagnetic layer 11. The state of magnetization is shown. As shown in FIG. 9, the first ferromagnetic layer 11 in the magneto-sensitive region 100 is made into a single magnetic domain by the bias magnetic field from the permanent magnet film 23.

FIG. 9C shows the case where the element receives the medium magnetic field, and FIG. 9D shows the case where the element receives the medium magnetic field in the opposite direction to that of FIG. The magnetization is
Indicates that it is changing in response to the medium magnetic field. At this time, the magnetization of the magneto-sensitive region 100 does not change uniformly, but the change becomes small near the junction region where the influence of the bias magnetization from the permanent magnet is large. This causes the following problems as the width of the magneto-sensitive area becomes narrower with the improvement in recording density.

That is, with reference to FIG.
As shown in (a), the magneto-sensitive area 1 that defines the track width
When the width of 00 is small, the medium is magnetized. In this case, the sensitivity of the magnetization of the first ferromagnetic layer 11 in the spin valve layer 10 is reduced. This is a change from the absence of the medium magnetic field shown in (b), as shown in (c) and (d), as shown in FIG. The reason for this is that the influence of becomes relatively large. For this reason, the output of the reproducing head is greatly reduced more than a reduction amount proportional to the reduction of the track width. In particular, in a super-high-density region where the track width is submicron, that is, 0.5 μm or less, the situation exactly as shown in FIG. 10 is obtained.
Reproduction of an ultra-high-density region of μm or less was impossible. As a result, a magnetic storage device that performs recording and reproduction with a surface recording density exceeding 20 gigabits / square inch has not been realized.

[0011]

However, the improvement in magnetic recording density in recent years has been remarkable, and there is a demand for reproduction in an ultra-high-density region of 0.5 μm or less. For this reason, when the track width of the reproducing head is reduced, it is possible to prevent the reproduction output from being greatly reduced more than the above-described reduction amount proportional to the reduction in the track width, and to achieve high output even in a narrow track. Requires a suitable reproducing head.

Accordingly, it is an object of the present invention to provide a high-output magnetoresistive head corresponding to a narrow track width.

Another object of the present invention is to provide a method of manufacturing a magnetoresistive head which can easily and surely manufacture such a magnetoresistive head.

It is a further object of the present invention to provide a magnetic storage device capable of performing recording and reproduction with a surface recording density exceeding 20 gigabits / square inch using such a magnetoresistive head.

[0015]

According to another aspect of the present invention, there is provided a magnetoresistive head having a magnetosensitive region having a magnetoresistive effect for sensing a magnetic field of a medium, and a current flowing in the magnetosensitive region. A pair of electrode films spaced apart from each other,
In a magnetoresistive head having a magnetoresistive element including a pair of spaced permanent magnet films for applying a bias magnetic field to the magnetosensitive region, an effective reproduction track width is 0.1 μm to 0.5 μm. The distance between the pair of permanent magnet films is 0.3 μm to 10 μm longer than the distance between the pair of electrode films.

FIG. 1 shows an element structure of the present invention. In FIG. 1, it is assumed that a spin-valve film is used in a magneto-sensitive region where the medium magnetic field is detected. (A) shows the layer configuration when the element is viewed from the medium facing surface. A spin valve layer, which is a magnetically sensitive region 100 wider than the track width, that is, a permanent magnet film 23 for applying a bias magnetic field and an electrode film 24 for supplying a sense current are laminated on both ends of the magnetically sensitive region 100. Is set smaller than the inter-electrode film Ll. By doing so, a region in the free layer (first ferromagnetic layer) 11 in the spin valve film described below that is highly sensitive to the medium magnetic field can be used as a reproduction track.

FIG. 1B shows the state of magnetization of the free layer 11 whose magnetization changes with an external magnetic field in the spin valve film 10 when there is no medium magnetic field, and the permanent magnet film 23 that biases the free layer 11. 3 shows the state of magnetization. FIG. 1 (b)
As shown in (1), the magneto-sensitive film 11 in the magneto-sensitive area 100 is made into a single magnetic domain by the bias magnetic field from the permanent magnet film 23. FIG. 1C shows a case where the element receives a medium magnetic field, and FIG.
3C shows a case where a medium magnetic field in a direction opposite to that of FIG. 3C is received, and shows that the magnetization of the free layer 11 changes in response to the medium magnetic field. At this time, the magnetization of the free layer 11 does not change uniformly, but the change becomes small near the junction region where the influence of the bias magnetic field from the permanent magnet film 23 is large. Therefore, the electrode film 24 is extended in the direction of the center where the magnetization in the free layer 11 is largely changed, and the track width is defined by the distance L1 between the electrodes. Ll). This effect is obtained when the track width is small and Ll is substantially 0.5 μm or less, and specifically, (0.1 to 0.1 μm).
0.5 μm). The positional relationship between the track width L1 and the width of the spin valve 10, that is, the interval L2 between the permanent magnet films 23 is defined from the results shown in FIG.

FIG. 2 shows a magneto-sensitive region 100 of the device shown in FIG.
Of the heads manufactured by making the centers of Ll and L2 coincide with the center of the head and changing the amount of displacement between the permanent magnet film and the electrode film represented by (L2-Ll) / 2 Is shown. The reproduction track width is less than 0.5 μm. The output increases as the position of the magnet film moves backward with respect to the position of the electrode film. This is because, as shown in FIG. 1, a portion having a higher magnetic field sensitivity in the magneto-sensitive region 100 where the magnetic field is detected can be used as the track width. FIG.
It can be seen from the above that by setting (L2−L1) /2≧0.15 μm, it is possible to obtain a high-output narrow-track reproducing element which is not affected by a low-sensitivity portion in the magnetosensitive region 100. Therefore, the difference between the distance L2 between the electrode films 24 and the distance L1 between the permanent magnet films 23 is 0.3 μm to 10 μm.
It is necessary to be above. (L2-L1) in FIG.
/ 2 = 0 corresponds to the conventional example shown in FIG. The difference between the distance L2 between the electrode films 24 and the distance L1 between the permanent magnet films 23 is suitably not more than 10 μm. This is because the width of the pattern exposed on the medium facing surface is not excessively increased.

Japanese Patent Application Laid-Open No. 7-307012 proposes to use the central portion of the magneto-sensitive region where the movement of magnetization is not suppressed by the permanent magnet film by making the distance between the electrodes narrower than the magneto-sensitive region. However, the prior art of this publication shows a case where the track width is larger than 0.5 μm, and does not assume a case where the track width is smaller than 0.5 μm.

In the present invention, the optimum inter-electrode width when the track width is smaller than 0.5 μm is obtained by experiments.

According to a second aspect of the present invention, there is provided a magnetoresistive head according to the first aspect.
The magneto-sensitive region includes a spin valve layer in which a change in electric resistance is proportional to a cosine between the magnetization directions of the two magnetic layers facing each other via the non-magnetic layer.

According to the invention having such a configuration, the effect of defining the electrode-to-electrode width and the permanent magnet film interval is maximized by using the magnetically sensitive region as the spin valve layer.

According to a third aspect of the invention, there is provided a magnetoresistive head.
3. The magnetoresistive head according to claim 1, wherein
Among the two magnetic layers constituting the spin valve layer, the pair of permanent magnet films are joined to a rotating magnetization layer whose magnetization changes, and a bias magnetic field is applied.

According to the invention having such a configuration, it is possible to achieve the object of the present invention in which high sensitivity is achieved by eliminating the adverse effect of the permanent magnet film in which the rotational magnetization layer of the spin valve layer is made into a single magnetic domain.

According to a fourth aspect of the present invention, in the method of manufacturing a magnetoresistive head, the effective reproduction track width is 0.1 μm to 0.1 μm.
In the method of manufacturing a magnetoresistive head of 5 μm, a step of forming a laminated film to be a magnetically sensitive region having a magnetoresistive effect for magnetically detecting a medium magnetic field; Patterning a resist film;
Patterning the laminated film to be the magnetically sensitive region using the first photoresist film as a mask to form a magnetically sensitive region; and applying a bias magnetic field to the magnetically sensitive region using the first photoresist film used in the step as a mask. A step of lifting off the first photoresist film after forming a pair of spaced apart permanent magnet films, and forming a second photoresist film narrower in the track width direction than the first photoresist film. And a step of using the second photoresist film as a mask to reduce the distance between the pair of permanent magnet films by 0.1 mm.
Forming a pair of electrode films having a small distance from each other by 3 μm to 10 μm, and then lifting off the second photoresist film.

According to such an invention, the width between the electrodes is made smaller than the width between the permanent magnet films, and the magnetoresistive head having a high sensitivity in a narrow track using a sensitive area in the center of the magnetosensitive area. Can be reliably manufactured.

According to a fifth aspect of the present invention, there is provided a method of manufacturing a magnetoresistive head according to the fourth aspect, wherein the step of forming the electrode film is performed in a direction in which sputtered particles fly. It is characterized by being a sputtering method having high performance.

According to the invention, it is possible to form an electrode film with an accurate width required for a magnetoresistive head having a narrow track width.

According to a sixth aspect of the present invention, in the method of manufacturing a magnetoresistive head according to the fifth aspect, the sputtering method is an ion beam sputtering method.

According to such an invention, the electrode spacing can be accurately formed by the ion beam sputtering method having high directivity.

According to a seventh aspect of the present invention, in the method of manufacturing a magnetoresistive head according to the sixth aspect, the gas pressure in the ion beam sputtering method is 1 × 10 ^-5 to 1 ×. 10 ^-3 Torr.

According to the present invention, sputtered particles having excellent directivity can be obtained, and the electrode interval can be accurately formed.

According to a eighth aspect of the present invention, in the method of manufacturing a magnetoresistive head according to the sixth or seventh aspect, the distance between the target surface and the substrate in the ion beam sputtering method is 20 or less. ~ 100
cm.

According to the invention, it is possible to obtain sputtered particles having a uniform flying direction, and it is possible to accurately form an electrode interval.

According to a ninth aspect of the present invention, there is provided a magnetic recording medium for magnetically recording information, and a recording head for generating a magnetic field corresponding to an electric signal and recording the information on the magnetic recording medium with the magnetic field. A magnetic storage device comprising a reproducing head for converting a change in a magnetic field leaking from the magnetic recording medium into an electric signal, wherein the reproducing head has a magneto-sensitive region having a magneto-resistance effect for detecting a medium magnetic field; A pair of spaced apart electrode films for supplying current to the magnetic region,
A magnetoresistive element including a pair of spaced permanent magnet films that apply a bias magnetic field to the magneto-sensitive region,
A magnetoresistive head having an effective reproduction track width of 0.1 μm to 0.5 μm and a separation distance between the pair of permanent magnet films of 0.3 μm to 10 μm longer than a distance between the pair of electrode films. There is a configuration.

According to the invention having such a configuration, since the above-described magnetoresistive head according to the present invention is used as a reproducing head, it is possible to reproduce with high output even with a narrow track width.

According to a tenth aspect of the present invention, in the magnetic storage device of the ninth aspect, when the magnetic recording medium has a coercive force of 2500 Oe to 4000 Oe, the areal recording density is 20 gigabits / square inch to 100 gigabits. / Square inch.

According to the invention, it is possible to achieve a high areal recording density, which could not be achieved until now.

[0039]

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

FIG. 1A is a configuration diagram showing a main part of a magnetoresistive head according to the present invention. A pair of permanent magnet films 23 separated from each other and joined to the rotating magnetic layer 11 shown in FIG. 7 of the magnetic sensing region 100 are arranged on both side surfaces of the magnetic sensing region 100 wider than the track width. A single magnetic domain is formed by applying a bias magnetic field. A pair of electrode films 24 spaced apart from each other is stacked on the permanent magnet film 23, and the ends of the opposing electrode films 24 also overlap the magneto-sensitive region 100. The center of the gap between the electrode films 24 substantially coincides with the center of the magneto-sensitive region 100 in the track width direction.

The separation distance L1 of the electrode film 24 is substantially the track width, and is 0.1 μm to 0.5 μm. One end side is shorter by 0.15 μm to 5 μm than the separation distance L2 between the front ends in the track width direction of the permanent magnet film 23, and the total of both ends is shorter by 0.3 μm to 10 μm.
As described above, by reducing the width between the electrode films 24 by 0.15 μm to 5 μm at a time from the separation distance of the permanent magnet film 23, the track width becomes 0.1 μm to 0.5 μm as shown in FIG.
Even with a narrow track width of m, high output can be obtained.

When the magneto-sensitive region 100 is the spin valve layer 10 shown in FIG. 7, the configuration of the present invention is most utilized. The spin valve layer 10 includes a first ferromagnetic layer 11 serving as a free layer formed of, for example, NiFe, CoFe, or CoFe.
The nonmagnetic layer 12 is made of, for example, 1-5 nm of copper, and has a thickness of 2-15 nm using NiFe or the like.
For example, NiFe is used as a fixed layer in a thickness of 1 to 5 nm. For example, PtMn, N
iO is used and has a thickness of 20 to 80 nm.

As the permanent magnet film 23, for example, Co
A CrPt-based alloy is used and has a thickness of 4 to 30 nm. This permanent magnet film 23 is joined to the free layer 11 as a magnetic domain control layer of the free layer 11. The pair of electrode films 24 are made of, for example, a metal such as Au, Cu, or Ta.

FIG. 2 is a sectional view of a read / write composite head using such a magnetoresistive element. In this recording / reproducing head, a lower shield layer 21 and a lower gap layer 22 are sequentially laminated on a ceramic base 20 serving as a slider, and a spin valve layer 10 having a track width is formed thereon. A permanent magnet film 23 for applying a bias magnetic field to the magnetization rotation layer of the spin valve layer to form a single magnetic domain is formed on both ends of the spin valve layer 10 in the track width direction, and a current is applied to the spin valve layer on the permanent magnet film. An electrode film 24 to be supplied is formed. The laminated film of the permanent magnet film 23 and the electrode film 24 has a structure in which the spin valve layer 10 is sandwiched at both ends in the track width direction. The distance L1 between the electrode films 24 is substantially the track width, and is 0.3 μm to 10 μm smaller than the distance L2 between the permanent magnet films 23. On these, a recording magnetic pole 28 is formed via an upper gap layer 25, an upper shield layer 26 also serving as a recording magnetic pole, and a recording gap layer 27. Further, a protective layer 29 covering them is provided. Between the recording magnetic poles 26 and 27, an exciting coil (not shown) insulated by a photoresist in the depth direction of the drawing is provided.

A method of manufacturing a magnetoresistive head according to the present invention will be described with reference to FIG. First, as shown in FIG. 5A, a spin valve film 10a for forming a magnetically sensitive region for sensing a medium magnetic field is formed. This spin valve film 1
Although not shown in FIG. 5, Oa is formed on a substrate on which a lower shield layer and a lower gap layer are stacked. The structure of the spin valve film 10a is the same as that shown in FIG.

Next, as shown in FIG. 5B, a first photoresist pattern R1 for patterning the spin valve film 10a is formed on the spin valve film 10a. The first photoresist pattern R1 is formed in a two-step shape or a reverse taper shape in which the base end side is thin.

Next, as shown in FIG. 5C, using the first photoresist R1 as a mask, the spin-valve film 10a is patterned by ion beam etching to form the magnetosensitive region 100. This etching is performed so that the end of the magneto-sensitive region 100 has an inclination from the shape of the first photoresist R1.

Next, as shown in FIG. 5D, a permanent magnet film for applying a bias magnetic field to the magneto-sensitive region 100 is formed.
The permanent magnet film 23 is formed by lift-off.

In the conventional device structure, since the permanent magnet film and the electrode film are formed at the same distance, FIGS.
As shown in (e), a photoresist film R3 is formed on the spin-valve film 10a, and the spin-valve film is etched to form the magneto-sensitive region 100. Then, the photomask R3 is formed.
Is used to form a permanent magnet film 231 and an electrode film 241 continuously, and lift off.

On the other hand, in the present invention, after the permanent magnet film 23 is formed and lifted off, the first photomask R1 is removed.
As shown in FIG. 5E, a first photomask R1 is newly added.
After forming the second photomask R2 having a smaller width, the electrode film 24 is formed by an ion beam sputtering method as shown in FIG.

In forming the permanent magnet film 23 and the electrode film 24, the present embodiment uses an ion beam sputtering method. In a conventional device, since a track width is wide, a normal RF sputtering method or a magnetron sputtering method is sufficient when a permanent magnet film or an electrode film is formed. However, in the present invention having a track width of 0.5 μm or less, these methods are not sufficient.

FIGS. 12 (a) to 12 (g) show the same steps as those of FIG. 5 in which the spin valve film 10 is formed using the first photomask R4.
is etched to form a permanent magnet film 232 by sputtering, and using the second photomask R5 as a mask, the electrode film 24 is formed using a normal RF sputtering method or magnetron sputtering method.
When film No. 2 is formed, the influence of the electrode film 242 wrapping around the photomask R5 is increased because the element has a narrow track width, which indicates that burrs having the mask R5 as a wall are generated. The burrs cause problems such as a decrease in the insulation resistance of the element.

FIGS. 13 (a) to 13 (g) show the same process as in FIG. 5 in which the spin valve film 10a is etched using the first photomask R6 to form the permanent magnet film 233 by sputtering. When the second photomask R7 is formed, the stem of the photomask R7 disappears due to the narrowing of the width of the second photomask R7, and the photomask R7 is formed in a bridge shape in the front-back direction of the drawing. . In this case, when the electrode film 243 is formed by using a normal RF sputtering method or a magnetron spar method, a short circuit occurs due to the wraparound of the electrode film 243.

As described above, in order to define the narrow reproduction width by the electrode film interval, the flying particles of the film to be deposited are different from the ordinary RF sputtering method or magnetron sputtering method.
That is, a special film forming technique that has a small dispersion of the incident angle of the substrate of the spack particles, that is, a high directivity is required.

According to the present invention, the ion beam sputtering method was found to be the most suitable as the film forming technique having a high directivity, and by applying this method to the manufacturing process of the present invention, a high output with a narrow track was obtained. The device can be manufactured reliably. In the ion beam sputtering method, the gas pressure of argon or the like during film formation is set to 1 × 10 ⁻⁵ to 1 × 10 ⁻³ To.
Since rr can be reduced to as low as rr, scattering of gas due to the spack particles can be suppressed, and the distance between the base material (target) for diverging sputtered particles and the substrate on which the film is deposited is set at 20.
Since it is easy to increase the length to about 100 cm to about 100 cm, it is possible to form a film by depositing sputter particles having a uniform flight direction.

Further, since the temperature of the substrate at the time of film formation is kept low, the photoresist mask is not deformed by heat, so that the electrode interval can be accurately formed. If the gas pressure of argon or the like during film formation exceeds 1 × 10 ⁻³ (Torr), the scattering of sputter particles due to the gas becomes large, and the dispersion of the sputter particles in the flying direction becomes remarkable.
^If the distance is lower than ^-5 (Torr), the stability of the ion beam is reduced. If the distance between the target and the substrate is shortened to 20 cm or less, it is difficult to align the flying directions of the spar particles, and the distance between the target and the substrate is 100 cm or more. Then, the problem that the equipment becomes too large becomes remarkable.
For the first time, an element having a reproduction track width of 0.5 μm or less can be easily realized by the process of the present invention in which the ion beam spatter method is introduced. Note that the lower limit of the track width according to the present method is preferably about 0.1 μm from the limit of lift-off of the electrode film.

According to the present invention, the reproduction track width is 0.5 μm.
Since the following high-density heads have been realized, mounting them will realize a magnetic storage device having a surface recording density of 20 gigabits / square inch or more. FIG. 6 shows the configuration of the magnetic storage device.

The magnetic storage device shown in FIG. 6 has a recording / reproducing head 10 according to the present invention as shown in FIG. 3 which faces a magnetic storage surface of a magnetic medium 102 rotated by a driving motor 101.
3 is attached by a suspension 104 and an arm 105, and is tracked by a voice coil motor (VCM) 106. The recording / reproducing operation is performed by a signal from the recording / reproducing channel 107 to the head 103. The control unit 108 controls the recording / reproducing channel 107, the VCM 106 for positioning the head 103, and the drive motor 101 for rotating the magnetic medium 102.

In the above magnetic storage device, the magnetic medium 1
By setting the coercive force of No. 02 to 2500 Oe to 4000 Oe, recording of 20 gigabits / square inch to 100 gigabits / square inch became possible. Further, when combined with the magnetic head 103 having a narrow track according to the present invention, a magnetic storage device having an areal recording density of 20 gigabits / square inch or more was realized.

[0060]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

[Embodiment 1] FIG. 3 shows a structure of a combined spin-valve reproducing / inductive recording head according to the present invention as viewed from the medium facing surface (ABS). On the Al ₂ O ₃ —TiC ceramic substrate 20 serving as a slider, CoTaZ
Lower shield layer 21 of 1 μm in thickness consisting of an r film, thickness of 80
After forming the lower gap layer 22 made of an alumina film having a thickness of 10 nm, a spin valve element shown below was formed.

The spin valve pattern serving as the magneto-sensitive region 100 includes a Ta underlayer having a thickness of 3 nm, a PtMn film having a thickness of 25 nm as the antiferromagnetic layer 14, a CoFe film having a thickness of 4 nm as the second ferromagnetic layer 13, 2.7 n film thickness as the magnetic layer 12
m Cu film, 1 nm thick Co as the first ferromagnetic layer 11
Fe film, 8 nm thick NiFe film, 3 nm thick Ta
It consists of a protective film. The width L2 of the magneto-sensitive area 100 is set to 0.4 μm.
m, 0.6μm, 0.7μm, 0.8μm, 1.0μ
m and 1.2 μm, and a permanent magnet film 23 for applying a bias magnetic field to the magneto-sensitive region was arranged at the end. The permanent magnet film 23 is mainly composed of CoPt and has a thickness of 30 nm.
It is. By inserting a 10 nm-thick Cr film as the base film, the coercive force of the CoPt film can be increased. An electrode film 24 made of a 50 nm-thick Au film was arranged on the magneto-sensitive region 100 with an interval L1 of 0.4 μm therebetween. The center points of L1 and L2 were almost matched.

A film having a thickness of 6
An upper gap layer 25 made of a 0 nm alumina film, an upper shield film 26 made of a 3 μm-thick NiFe film also used as a recording magnetic pole, and a recording gap 27 made of a 0.2 μm-thick alumina film are formed. , Film thickness 2.5 μm
The recording magnetic pole 28 made of the CoFeNi film was formed. An exciting coil (not shown) insulated by a photoresist in the depth direction of FIG. 3 was formed between the recording magnetic poles 26 and 27. Further, a protective layer 29 was formed to cover the recording magnetic pole 28.

The head described above was subjected to a coercive force of 2500 Oe in C
The recording / reproducing characteristics were evaluated using a magnetic medium composed of an oCrPt magnetic film. As a result, an effective reproduction track width of 0.5 μm or less was obtained. As shown in FIG. 2, the reproduction output is a spin valve pattern width L2 (that is, a permanent magnet film width), in this case, 0.4 μm, 0.6 μm,
0.7 μm, 0.8 μm, 1.0 μm, 1.2 μm,
When the value ((L2−L1) / 2) that is half of the difference between the electrode spacing L1 and 0.4 μm in this case is 0.15 μm or more,
Almost constant high output was obtained.

[Embodiment 2] FIG. 4 shows a structure of a combined spin-valve reproducing / inductive recording head according to the present invention as viewed from the medium facing surface (ABS). On the A1203-TiC ceramic substrate 20 serving as a slider, CoTa
After forming a lower shield layer 21 made of a ZrCr film and having a thickness of 1 μm and a lower gap layer 22 made of an alumina film having a thickness of 80 nm, a magneto-sensitive region 100 ′ shown below was formed.

The magneto-sensitive region 100 'includes a spin valve film, a 3 nm thick Zr base film, and a 30 nm thick PtMn film.
Film, 3.5 nm thick CoFe film, 2.5 nm thick C
u film, 1 nm thick CoFe film, 7 nm thick NiFe
The film is made of a Ta protective film having a thickness of 3 nm. This magnetic sensing area 1
00 'was not patterned.

On the magneto-sensitive area 100 ', a permanent magnet film 23' for applying a bias magnetic field was arranged. The permanent magnet film 23 'contains CoPt as a main component and has a thickness of 30 nm. By inserting a 10 nm-thick Cr film as the base film, the coercive force of the CoPt film can be increased. The permanent magnet film interval L2 is 0.4 μm, 0.6 μm
m, 0.7 μm, 0.8 μm, 1.0 μm, 1.2 μm
6 types. Further, an electrode film 24 ′ made of an Au film having a film thickness of 75 nm was arranged at an interval Ll of 0.4 μm. The center points of L1 and L2 were almost matched.

On the magneto-sensitive area 100 ', a film thickness of 60 n
An upper gap layer 25 made of an alumina film having a thickness of m and an upper shield film 26 made of a NiFe film having a thickness of 3 μm also serving as a recording magnetic pole are formed. , 2.5 μm thick C
A recording magnetic pole 28 made of an oFeNi film was formed. An exciting coil (not shown) insulated by a photoresist was formed between the recording magnetic poles 26 and 27 in the depth direction of FIG.
The recording / reproducing characteristics of the above head were evaluated using a magnetic medium comprising a CoCrPt magnetic film having a coercive force of 2500 Oe.

As a result, an effective reproduction track width of 0.1 μm to 0.5 μm was obtained. As shown in FIG. 2, the reproduction output is a permanent magnet film width L2, in this case, 0.4.
μm, 0.6 μm, 0.7 μm, 0.8 μm, 1.0 μ
m, 1.2 μm and electrode spacing L1, in this case 0.4 μm
The half value of the difference ((L2-L1) / 2) is 0.15 μm.
m, an almost constant high output was obtained.

[Embodiment 3] An embodiment of a method for manufacturing a magnetoresistive head according to the present invention shown in FIG. 2 will be described with reference to FIG.

As shown in (a), first, a spin valve film 10a is formed. Although the film is formed by the magnetron sputtering method, it can be formed by a radio frequency (RF) sputtering method or an ion beam sputtering method.

Next, as shown in (b), a photoresist pattern R1 for patterning the spin valve film 10a is formed. The photoresist material is pattern R1
By changing the resist material forming the stalk portion and the material forming the upper head portion, the shape shown by R1 in which the upper head portion was wider than the stalk portion shown in (b) was obtained.

Next, as shown in (c), the spin valve film 10a is patterned by ion beam etching using a photoresist pattern R1.

Next, as shown in (d), the permanent magnet film 2 for applying a bias magnetic field to the spin valve 10 in the magneto-sensitive region.
3 Film formation and lift-off. In this step, a film was formed by an ion beam sparging method. This step can be performed by a magnetron sputtering method or a radio frequency (RF) sputtering method.

Next, as shown in (e), a photomask R2 having a smaller width than the photomask R1 is newly formed. At this time, the center of the photomask R2 was made to coincide with the center of the photomask R1 as much as possible.

Next, as shown in (f), an electrode film 23 is formed. The Au film was used as the electrode material.
a is also possible. In the present invention, in order to carry out this step, it has been discovered that the ion beam spatter method is the most suitable as a film forming technique having high directivity, and applied. In the ion beam sparging method, the gas pressure of argon or the like at the time of film formation can be reduced to 1 × 10 ⁻⁴ (Torr) or less.
Base material (target) that further emits spar particles
In addition, since it is easy to increase the distance from the substrate on which the film is deposited to 20 cm or more, it was possible to form a film by depositing sputter particles having a uniform flight direction. Further, since the temperature of the substrate at the time of film formation was kept low, the photoresist mask R2 was not deformed by heat, so that the electrode interval could be accurately formed. At this time, the gas pressure of argon or the like at the time of film formation is 1 × 10 ⁻³ (To
If rr) is exceeded, the scattering of sputtered particles due to gas becomes large, and the dispersion of the sputtered particles in the flying direction becomes remarkable. If the distance between the target and the substrate becomes shorter than 20 cm, it becomes difficult to align the flying directions of the sputtered particles. thing,
Such a problem was remarkable. From this, while using the ion beam sputtering method, more preferably,
It can be said that it is preferable that the argon gas pressure at the time of film formation be as low as 1 × 10 ⁻⁴ (Torr) or less and the distance between the target and the substrate on which the film is deposited is as long as 20 cm or more.

Next, as shown in (g), the photoresist mask R2 was removed to complete the device. For the first time, an element having a reproduction track width of 0.5 μm or less can be easily realized by the steps of the present invention in which the above-described ion beam sputtering method is introduced. The lower limit of the track width according to this method was 0.1 μm.

As a comparative example of the production method of the present invention, (f)
The problems identified in the step (3) when using a normal RF sputtering method or a magnetron sputtering method that has been used in the conventional device fabrication will be described below.

FIG. 12 shows a case where an electrode film is formed by using a normal RF sputtering method or a magnetron sputtering method. Since the element has a narrow track width, the influence of the electrode 242 wrapping around the photomask is increased, and it has been confirmed that burrs having the mask as a wall are generated. The burrs caused problems such as a decrease in insulation resistance of the element.

FIG. 12 shows a case where the stem of the photomask R7 disappears because the width of the photomask R7 is narrow, and the photomask R7 is formed in a bridge shape in the front-back direction of the drawing. In this case, when the electrode film was formed by using the normal RF sputtering method or the magnetron sputtering method, an electric short circuit occurred due to the wraparound of the electrode film. As described above, in order to define the narrow reproduction width by the electrode interval, it has not been possible to realize the normal RF sputtering method or the magnetron sputtering method.

[0081]

As described above, according to the magnetoresistive head of the present invention, in order to perform high-density recording and reproduction,
When the track width of the reproducing head is narrowed, it is possible to prevent the reproduction output from being greatly reduced more than a reduction amount proportional to the decrease in the track width, and high output can be obtained even in a narrow track of 0.5 μm or less. A reproducing head can be realized.

Further, according to the method of manufacturing a magnetoresistive head of the present invention, a magnetoresistive head capable of reproducing with high output even with such a narrow track width can be surely manufactured.

Further, according to the magnetic storage device of the present invention, since the magnetoresistive head of the present invention is used for the reproducing head, the coercive force of the magnetic medium is set to 2500 Oe or more, so that the areal recording density becomes 20%. Gigabits per square inch or more.

[Brief description of the drawings]

FIG. 1A is a cross-sectional view showing an element configuration of a magnetoresistive head according to the present invention, and FIGS. 1B to 1D are schematic views showing magnetization behavior of a magnetic film.

FIG. 2 is a graph showing how a normalized output changes with an electrode film interval.

FIG. 3 is a sectional view showing a configuration of an embodiment of a recording / reproducing head according to the present invention.

FIG. 4 is a sectional view showing a configuration of an embodiment of a recording / reproducing head according to the present invention.

FIGS. 5A to 5G are cross-sectional views showing the steps of manufacturing the magnetoresistive head of the present invention.

FIG. 6 is a configuration diagram showing a configuration of a magnetic storage device according to the present invention.

FIG. 7 is a schematic diagram showing a configuration of a spin valve film.

FIG. 8 is a sectional view showing a configuration of a conventional magnetic recording / reproducing head.

FIG. 9A is a cross-sectional view showing the element configuration of a conventional magnetoresistive head, and FIGS. 9B to 9D show the magnetization behavior of a magnetic film.

FIG. 10 is a cross-sectional view showing an element structure when a track width in a conventional magnetoresistive head is reduced,
(B) to (d) show the magnetization behavior of the magnetic film.

FIGS. 11A to 11E are flowcharts showing a conventional method for manufacturing a magnetoresistive head.

12 (a) to 12 (g) are flowcharts for explaining generation of burrs in a conventional method of manufacturing a magnetoresistive head.

FIGS. 13A to 13G are flowcharts for explaining problems in a conventional method of manufacturing a magnetoresistive head.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 magnetic sensitive region 10 spin valve layer 11 (first ferromagnetic layer) rotating magnetization layer 23 permanent magnet film 24 electrode film L1 separation distance between electrode films L2 separation distance between permanent magnet films

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Seiman Nagahara 5-7-1 Shiba, Minato-ku, Tokyo Inside NEC Corporation (72) Inventor Shigeru Mori 5-7-1 Shiba, Minato-ku, Tokyo NEC Corporation F term (reference) 5D034 BA03 BA05 BA09 CA04 DA07

Claims (10)

[Claims] 1. A magneto-sensitive area having a magnetoresistive effect for sensing a medium magnetic field, a pair of electrode films separated from each other for supplying a current to the magneto-sensitive area, and a pair of electrode films separated from each other for applying a bias magnetic field to the magneto-sensitive area. In a magnetoresistive head having a magnetoresistive element having a pair of spaced permanent magnet films, an effective reproduction track width is 0.1 μm to 0.5 μm
Wherein the distance between the pair of permanent magnet films is 0.3 μm to 10 μm than the distance between the pair of electrode films. 2. The magneto-resistive head according to claim 1, wherein the magneto-sensitive region has a change in electric resistance proportional to a cosine between directions of magnetization of two magnetic layers opposed to each other via the non-magnetic layer. A magnetoresistive head comprising a spin valve layer. 3. The magnetoresistive head according to claim 1, wherein, of the two magnetic layers constituting the spin-valve layer, the pair of permanent magnet films are arranged with respect to a rotating magnetic layer whose magnetization changes. A magnetoresistive head, wherein a bias magnetic field is applied by bonding. 4. An effective reproduction track width is 0.1 μm or more.
In a method of manufacturing a 0.5 μm magnetoresistive head, a step of forming a laminated film that becomes a magneto-sensitive region having a magneto-resistive effect of magneto-optically detecting a medium magnetic field; (1) a step of patterning a photoresist film, a step of patterning a laminated film to be the magnetically sensitive region using the first photoresist film as a mask to form a magnetically sensitive region, and a first photoresist film used in the step. After forming a pair of spaced apart permanent magnet films for applying a bias magnetic field to the magneto-sensitive area using the
Lifting off the photoresist film, forming a second photoresist film having a smaller width in the track width direction than the first photoresist film, and using the second photoresist film as a mask, the pair of permanent magnet films Forming a pair of electrode films whose distance from each other is narrower by 0.3 μm to 10 μm than the distance between them, and then lifting off the second photoresist film. Production method. 5. The method of manufacturing a magnetoresistive head according to claim 4, wherein the step of forming the electrode film is a sputtering method having high directivity in a direction in which sputtered particles fly. A method for manufacturing a resistance effect type head. 6. The method of manufacturing a magnetoresistive head according to claim 5, wherein said sputtering method is an ion beam sputtering method. 7. The method of manufacturing a magnetoresistive head according to claim 6, wherein the gas pressure in said ion beam sputtering method is 1 × 10 ⁻⁵ to 1 × 10 ⁻³ Torr. Manufacturing method of effect type head. 8. The method of manufacturing a magnetoresistive head according to claim 6, wherein a distance between a target surface and a substrate in the ion beam sputtering method is 20 cm.
A method for manufacturing a magnetoresistive head, wherein 9. A magnetic recording medium for magnetically recording information, a recording head for generating a magnetic field corresponding to an electric signal, and recording the information on the magnetic recording medium by the magnetic field, and leaking from the magnetic recording medium. In a magnetic storage device having a reproducing head for converting a change in a magnetic field into an electric signal, the reproducing head includes a magneto-sensitive region having a magneto-resistance effect for detecting a medium magnetic field and a current supplying region for supplying a current to the magneto-sensitive region. The magnetoresistive element includes a pair of spaced electrode films and a pair of spaced permanent magnet films for applying a bias magnetic field to the magneto-sensitive region, and has an effective reproduction track width of 0.1 μm to 0.1 μm. 5 μm, and the distance between the pair of permanent magnet films is 0.3 μm more than the distance between the pair of electrode films.
A magnetic storage device characterized by being a magnetoresistive head of m to 10 μm long. 10. The magnetic storage device according to claim 9, wherein the magnetic recording medium has a coercive force of 2500 Oe to 4000 Oe.
A magnetic storage device which performs recording / reproduction with an areal recording density of 20 gigabits / square inch to 100 gigabits / square inch when Oe.