JP2000163717A - Magnetoresistive element - Google Patents

Abstract

(57) Abstract: A magnetoresistive element has a narrow read gap without deteriorating element characteristics. The magnetoresistive film has at least one antiferromagnetic layer and is patterned into an arbitrary shape.
And magnetic shield layers 2 and 1 provided above and below the magnetoresistive effect films 4 to 7 with the read gap layers 3 and 9 interposed therebetween.
A thin portion 8 having a thickness different from other portions is provided in a part of at least one antiferromagnetic layer 7 constituting a magnetoresistive element made of zero.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetoresistive element, and more particularly, to a hard disk drive (H).
The present invention relates to a magnetoresistive element characterized by a structure for thinning a spin valve film used for a read head of a magnetic recording device such as DD).

[0002]

2. Description of the Related Art Research and development of hard disk devices capable of high-density magnetic recording have been rapidly progressing with the recent demand for miniaturization and large-capacity hard disk devices. Higher sensitivity and miniaturization are also required for read head elements, and a magnetic sensor using a giant magnetoresistance (GMR) effect that can obtain a large output with a low magnetic field has been developed in terms of high sensitivity. ing.

For example, IBM has proposed a "magnetoresistive sensor utilizing the spin valve effect (see Japanese Patent Application Laid-Open No. 4-358310). This magnetic sensor comprises two magnetic layers separated by a non-magnetic metal layer. It has a non-coupled ferromagnetic layer, and an antiferromagnetic layer typified by FeMn is attached to one of the ferromagnetic layers to form a sandwich structure in which the magnetization M of the ferromagnetic layer is fixed. In view of the fact that a high magnetoresistance effect can be obtained with respect to a minute magnetic field from a recording medium, a conventional inductive head or AMR (Anisotropic Magneto-Re
It is much better than the film, and is used as a high-sensitivity readhead element.

In this magnetic sensor, when an external magnetic field is applied from a magnetic recording medium or the like, the magnetization direction of the other ferromagnetic layer whose magnetization is not fixed, ie, the free layer, matches the external magnetic field. The ferromagnetic layer having a fixed magnetization, that is, a pinned,
An angle difference will occur between the magnetization direction of the layer and the angle.

Since the scattering depending on the spin of the conduction electrons changes depending on the angle difference and the electric resistance changes, the change in the electric resistance is changed by flowing a constant sense current. As a result, the state of the external magnetic field, that is, the signal magnetic field from the magnetic recording medium is obtained, and the magnetoresistance change rate of this spin valve magnetoresistance sensor is about 5%.

[0006] To increase the efficiency of such a spin valve magnetoresistive sensor, IBM also used a "double spin-type magnetoresistive sensor".
A valve magnetoresistive sensor (see Japanese Patent Application Laid-Open No. 6-223336) has been proposed, and this dual (double) spin valve magnetoresistive sensor has a spin valve structure symmetrically stacked around a free layer. Yes, this configuration provides about twice the change in magnetoresistance.

In particular, as an antiferromagnetic layer of such a dual spin valve magnetoresistive sensor, a regular alloy type Pd
-When a Pt.Mn alloy is used (If necessary, refer to Japanese Patent Application
Unlike the conventional disordered alloy type FeMn, a fixed magnetic field, which is a vise magnetic field, can be applied to any of the upper and lower pinned layers.
A highly reliable dual structure spin valve magnetoresistive sensor can be easily formed. That is, in the case of FeMn conventionally used as an antiferromagnetic material layer, it becomes an antiferromagnetic material only when deposited on a film having an fcc (face-centered cubic) structure. There is a problem that it cannot be used as the upper pinned layer of the resistance sensor.

Here, the conventional spin valve element and dual spin valve element will be briefly described with reference to FIG. FIG. 7A is a schematic cross-sectional view of a principal part of a conventional spin valve element. First, Al ₂ O _{3 serving as} a base of a slider is shown.
Ni on the TiC substrate 41 via the Al ₂ O ₃ film 42
A lower shield layer 43 made of Fe alloy or the like is provided, and a lower read gap layer 44 made of Al ₂ O ₃ or the like is provided. Cu intermediate layer 46,
A pinned layer 47 made of CoFe or the like, and PdPtMn
A spin valve film to be a magnetoresistive element is formed by stacking antiferromagnetic layers 48 made of the same.

Next, after patterning the magnetoresistive element into a predetermined shape, a conductive film made of W or Au is deposited on both ends of the magnetoresistive element to form a lead electrode 49.
Then, an upper shield layer 51 made of a NiFe alloy or the like is provided again via an upper read gap layer 50 made of Al ₂ O ₃ or the like, thereby completing the basic structure of the spin valve element. In this case, after the free layer 45 to the antiferromagnetic layer 48 are sequentially deposited in a state where the first magnetic field is applied, the second layer orthogonal to the first magnetic field is formed in a vacuum.
Heat treatment in a state where a magnetic field of
By determining the magnetization direction of 8, the basic structure of the magnetoresistive element is formed.

The read gap in this spin valve element is a total of the thicknesses of the lower read gap layer 43, the free layer 45 to the antiferromagnetic layer 48, and the upper read gap layer 49.

FIG. 7B is a schematic view of a conventional dual spin valve element.
FIG. 2 is a cross-sectional view of a main part, and first, A, which is a base of the slider;
l_TwoO_ThreeAl on the TiC substrate 41_TwoO_ThreeThrough the membrane 42
To form a lower shield layer 43 made of NiFe alloy or the like.
And then Al _TwoO_ThreeLower lead gap consisting of
After the layer 44 is provided, an antiferromagnetic layer 5 such as PdPtMn
2. Pinned layer 53 made of CoFe or the like, Cu intermediate layer 5
4. Free layer 4 such as a laminated structure of NiFe and CoFe
5, Cu intermediate layer 46, pinned layer 4 made of CoFe or the like
7, and an antiferromagnetic layer 48 made of PdPtMn or the like.
Dual spin valves that are stacked to form a magnetoresistive element
A film is formed.

Next, after patterning the magnetoresistive element into a predetermined shape, a conductive film made of W or Au is deposited on both ends of the magnetoresistive element to form a lead electrode 49.
Then, an upper shield layer 51 made of a NiFe alloy or the like is provided again via an upper read gap layer 50 made of Al ₂ O ₃ or the like, thereby completing the basic structure of the dual spin valve element. In this case, the first
After the antiferromagnetic layer 52 to the antiferromagnetic layer 48 are sequentially deposited with the applied magnetic field, heat treatment is performed in a vacuum while a second magnetic field orthogonal to the first magnetic field is applied. By determining the magnetization directions of the antiferromagnetic layers 48 and 52, the basic structure of the magnetoresistive element is formed.

The read gap in this dual spin-valve element is the total of the thicknesses of the lower read gap layer 43, the antiferromagnetic layers 52 to 48, and the upper read gap layer 49.

In such a spin valve element, the magnetization directions of the pinned layers 47 and 53 are different from those of the antiferromagnetic layer 4 respectively.
The magnetization directions of the free layer 45 and the magnetization direction of the free layer 45 are substantially orthogonal to the magnetization directions of the pinned layers 47 and 53, and the external current is applied by flowing a sense current between the pair of lead electrodes 49. The magnetic field, that is, the magnetic field leaked from the magnetic recording medium is measured.

In recent years, the recording capacity of magnetic recording disks for computers has been increasing at a rate of 1.6 times a year, and a sufficient signal reproduction output can be obtained from recording bits that have been miniaturized by such a high density. For this reason, the narrowing of the read gap, which determines the bit length of the read signal, is becoming very important as well as the fine processing technology for the magnetoresistive element width, which is the read track width. This will be described with reference to FIG.

FIG. 8 is an explanatory diagram of the distance d between the upper and lower magnetic shield layers with respect to the magnetic recording medium 56, that is, the relationship between the read gap and the recording density. magnetoresistive element sandwiched 55 is will read the magnetic recording medium bit length recorded in the 56 L _b of the recording bit 57 which faces successively read gap d
When There too wide with respect to the bit length L _b of the recording bits 57, reading neighboring other than the recording bit 57 of the subject to the influence of the magnetic field of the recording bit 57, the position resolution is lowered, the reading target recording bit 57 The read gap d is set such that the magnetic fields of adjacent recording bits 57 other than the above are absorbed by the lower shield layer 43 and the upper shield layer 49.
So as to be less than twice the bit length L _b, i.e., d ≦ 2L _b
Has been adjusted.

[0017]

However, with the recent development of multimedia, there has been a demand for a higher density of the magnetic disk drive.
If the bit length _{Lb of the above} is further miniaturized, it is necessary to further narrow the read gap d.
Lower read gap layer 43 and upper read gap 49
, Or the magnetoresistive element 55 itself needs to be thinned.

However, when the lower read gap layer 43 and the upper read gap 49 are made thinner, the withstand voltage of the read gap layer becomes a problem, and there is a limit in making the read gap layer thinner.

On the other hand, when the magnetoresistive element 55 is made thinner, the antiferromagnetic layers 48 and 52 having the largest relative layer thickness are most effective. , 5
When the thickness of the layer 2 is reduced, the fixing force of the pinned layers 47 and 53 in the magnetization direction is weakened, and there is a problem that the element characteristics are deteriorated, and in particular, the magnetic field detection sensitivity is lowered.

Accordingly, it is an object of the present invention to narrow the read gap without deteriorating device characteristics.

[0021]

FIG. 1 is an explanatory view of the principle configuration of the present invention. Referring to FIG. 1, means for solving the problems in the present invention will be described. In addition, FIG.
FIG. 2 is a schematic cross-sectional view of a principal part of a spin valve element. See FIG. 1. (1) The present invention provides a magnetoresistive film 4 having at least one antiferromagnetic layer 7 and patterned into an arbitrary shape.
, And at least one antiferromagnetic layer 7 in the magnetoresistive element comprising the magnetic shield layers 2 and 10 provided above and below the magnetoresistive films 4 to 7 with the read gap layers 3 and 9 interposed therebetween. A thin part 8 with a thickness different from that of the other part
Is provided.

As described above, by providing the thin portion 8 having a thickness different from that of the other portion in at least one antiferromagnetic layer 7 of at least one layer, the fixed magnetic force on the pinned layer 6 can be reduced without reducing the fixed magnetic force. The thickness of the ferromagnetic layer 7 can be effectively reduced.

(2) Further, the present invention is characterized in that, in the above (1), the thin portion 8 is provided in a portion related to signal reading of the magnetoresistive element.

As described above, by providing the thin portion 8 in a portion related to signal reading of the magnetoresistive effect element, the read gap d can be reduced without reducing the fixed magnetic force on the pinned layer 6. Thereby, the reading sensitivity from a magnetic recording medium on which high-density recording has been performed can be improved.

(3) In the present invention, in the above (2), the magneto-resistive films 4 to 7 may include one or more magnetic films, a free layer 4, a non-magnetic layer 5, and one or more magnetic films. A pinned layer 6 and an antiferromagnetic layer 7 are sequentially stacked.

The configuration of the above (2) is the same as that of the magnetoresistive film 4
7 is a single layer having a structure in which a free layer 4 made of one or more magnetic films, a nonmagnetic layer 5, a pinned layer 6 made of one or more magnetic films, and an antiferromagnetic layer 7 are sequentially stacked. By applying the present invention to a spin valve element, the reading sensitivity of a single spin valve element can be improved. The antiferromagnetic layer 7 may be provided on the substrate 1 side, or may be provided on the top of the magnetoresistive films 4 to 7.

(4) The invention according to (2), wherein the magnetoresistive film is an antiferromagnetic layer, a pinned layer comprising one or more magnetic films, a nonmagnetic layer, or a magnetic layer comprising at least one magnetic layer. It has a structure in which a free layer 4 made of a film, a nonmagnetic layer 5, a pinned layer 6 made of one or more magnetic films, and an antiferromagnetic layer 7 are sequentially laminated.

In the configuration (2), the magnetoresistive effect film is an antiferromagnetic layer, a pinned layer composed of one or more magnetic films, a nonmagnetic layer, and a free layer composed of one or more magnetic films. ,
By applying the present invention to a dual spin valve element having a structure in which a nonmagnetic layer 5, a pinned layer 6 composed of one or more magnetic films, and an antiferromagnetic layer 7 are sequentially laminated, the read sensitivity of the dual spin valve element is obtained. Can be improved. The thin portion 8 may be provided on at least one of the antiferromagnetic layer on the substrate 1 side or the uppermost antiferromagnetic layer 7 of the magnetoresistive film. In addition, the effect of narrowing the read gap is maximized.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIGS.
Thus, the manufacture of the spin valve element according to the first embodiment of the present invention is described.
The fabrication process will be described. See FIG. 2 (a)._TwoO_Three-Sputtering on TiC substrate 11
Method of 2μm thick Al _TwoO_ThreeAfter depositing the film 12,
Using a selective electrolytic plating method, apply a magnetic field of 100 Oe
While forming a 3 μm thick NiFe film, for example.
To form a lower shield layer 13 and then a sputtering method
The thickness is, for example, 500 ° (= 50 nm) using
Al_TwoO_ThreeBy depositing a film, the lower read gap layer 14
I do.

Next, 30 Oe was used as a spin valve film.
After forming a Ta film 15 having a thickness of, for example, 50 ° as a base layer by using a sputtering method while applying a magnetic field of Ni, the NiFe free layer 1 having a thickness of, for example, 40 ° is formed.
6, the thickness is, for example, a 25 ° CoFe free layer 17, the thickness is, for example, a 25 ° Cu intermediate layer 18, the thickness is, for example, a 25 ° CoFe pinned layer 19, and the thickness is 10, for example.
A PdPtMn antiferromagnetic layer 20 of 0 to 300 °, for example, 250 ° is sequentially laminated. In this case, NiF
The composition of e is, for example, Ni ₈₁ Fe ₁₉ , the composition of CoFe is, for example, Co ₉₀ Fe ₁₀ , and PdPt
The composition of Mn is, for example, Pd ₃₁ Pt ₁₇ Mn ₅₂ .

Next, in order to fix the magnetization direction of the CoFe pinned layer 19, while applying a DC magnetic field of 100 kA / m in a direction orthogonal to the magnetic field applied at the time of film formation, at 230 ° C. for 1 to 3 hours in vacuum. The heat treatment of P
The magnetization direction of the dPtMn antiferromagnetic layer 20 is the direction of the applied DC magnetic field. In this case, in a heat treatment step at 230 ° C., Cu and NiF
In order to prevent mutual diffusion with the e-free layer 16, a CoFe free layer 17 serving as a barrier layer is provided between the two to form a two-layer free layer.

Next, referring to FIG. 2B, ion milling using Ar ions is performed using the resist pattern 21 as a mask to obtain PdP.
Only the portion to be the reading area of the tMn antiferromagnetic layer 20 is 2
Etching is performed so as to leave 0 to 100 °, for example, 50 ° to form a thinned portion 22 having a thickness of, for example, 50 °.

Next, after the resist pattern 21 is removed, a new photoresist is applied and patterned, and the resist pattern 23 formed by patterning is used as a mask to perform ion milling using Ar ions. , Pd
The PtMn antiferromagnetic layer 20 to the Ta film 15 are selectively etched to shape the device.

Next, after removing the resist pattern 23, a W film having a thickness of, for example, 1200 ° is deposited by a lift-off method using a resist pattern (not shown) to form one pair. Is formed, and then, again,
The thickness is, for example, 500 ° by the sputtering method.
Al ₂ O ₃ film is deposited, and the upper read gap layer 2 is formed.
5, and then the thickness was changed by selective electrolytic plating.
For example, by forming a 3.8 μm NiFe film to form the upper shield layer 26, the basic configuration of the single spin valve element is completed.

In this case, the read gap d is the distance between the lower shield layer 13 and the upper shield layer 26 at the position where the thinned portion 22 is provided. Therefore, d = 500 + 50 + 40 + 25 + 25 + 25 + 50 + 500 = 1215 (Å) The gap can be reduced by about 15% as compared with 1415 ° when the layered portion 22 is not provided.

As described above, the PdPtMn antiferromagnetic layer 20
In the case where the thinned portion 22 is provided in the reading region of the above, although the direct magnetization direction fixing force of the region corresponding to the thinned portion 22 of the CoFe pinned layer 19 is weakened, a sufficient thickness not involved in reading is required. Since the magnetization direction fixing force acting on both ends of the CoFe pinned layer 19 biased by the both ends of the PdPtMn antiferromagnetic layer 20 has the magnetization direction fixing force at the center of the CoFe pinned layer 19, the characteristics may be degraded. Absent.

Next, referring to FIG. 4 and FIG.
Manufacturing process of the dual spin valve element according to the second embodiment
The process will be described. See FIG. 4 (a)._TwoO_Three-Sputtering on TiC substrate 11
Method of 2μm thick Al _TwoO_ThreeAfter depositing the film 12,
Using a selective electrolytic plating method, apply a magnetic field of 100 Oe
While forming a 3 μm thick NiFe film, for example.
After forming the lower shield layer 13, the resist pattern is again
1 using a selective electrolytic plating method using
While applying a magnetic field of 00 Oe, the thickness is, for example, 20
At 0 °, a NiFe raised portion 28 having a width of 0.5 μm is formed.
To achieve.

Next, after the resist pattern 27 is removed, an Al film having a thickness of, for example, 500.degree.
_{A 2} O ₃ film is deposited to form a lower read gap layer 14,
Next, after providing a resist pattern 29, 30 Oe
A PdPtMn film having a thickness of, for example, 200 ° is deposited using a sputtering method while applying a magnetic field of
PdPt for embedding the step due to the NeFe raised portion 28
The Mn thick part 30 is formed.

Next, the PdPtMn film (not shown) deposited on the resist pattern 29 is simultaneously removed by removing the resist pattern 29, and then sputtering is performed again while applying a magnetic field of 30 Oe. Using a method, for example, a PdPtMn thin film portion 31 having a thickness of 50 °, a CoFe pinned layer 32 having a thickness of 25 °, for example,
For example, a Cu intermediate layer 33 of 25 °
5% CoFe film / 20% NiFe film / 25% Co
The free layer 34 of a three-layer structure made of Fe, the Cu intermediate layer 18 having a thickness of, for example, 25 °, and the thickness of, for example, 25 °
CoFe pinned layer 19 and a thickness of 100 to 300
{, For example, 250 ° PdPtMn antiferromagnetic layer 20
Are sequentially laminated. In this case, the composition of NiFe is, for example, Ni ₈₁ Fe ₁₉ and the composition of CoFe is
For example, a Co ₉₀ Fe _10, The composition of PdPtMn are, for example, Pd ₃₁ Pt ₁₇ Mn _52.

Next, in order to fix the magnetization directions of the CoFe pinned layers 19 and 32, while applying a DC magnetic field of 100 kA / m in a direction orthogonal to the magnetic field applied at the time of film formation,
By performing a heat treatment at 230 ° C. in a vacuum for 1 to 3 hours, the magnetization directions of the PdPtMn antiferromagnetic layer 20, the PdPtMn thick portion 30, and the PdPtMn thin film portion 31 are set to the direction of the applied DC magnetic field. Note that, in this case as well,
In the heat treatment process at 0 ° C., the Cu intermediate layers 18 and 33 and N are mixed so that mutual diffusion between Cu forming the Cu intermediate layers 18 and 33 and NiFe forming the free layer 34 does not occur.
A free layer 34 has a three-layer structure by providing a CoFe film serving as a barrier layer between the iFe film and the iFe film.

Next, as in the steps after FIG. 2B in the first embodiment, ion milling using Ar ions with a resist pattern (not shown) as a mask is performed as in the first embodiment. By doing so, only the portion to be the reading region of the PdPtMn antiferromagnetic material layer 20 is etched so as to leave 20 to 100 °, for example, 50 °, to form the thinned portion 22 having a thickness of, for example, 50 °.

Next, after removing the resist pattern, a PdPtMn solution is formed by applying ion milling using Ar ions using a resist pattern (not shown) formed by applying a new photoresist and patterning as a mask. Ferromagnetic layer 20 to Pd
The PtMn thick portion 30 is formed into an element shape by selective etching.

Next, after removing the resist pattern, a pair of lead electrodes 24 is formed again by depositing a W film having a thickness of, for example, 1200 ° by a lift-off method using a resist pattern (not shown). After that, an Al ₂ O ₃ film having a thickness of, for example, 500 ° is deposited again by a sputtering method to form an upper read gap layer 25, and then, by a selective electrolytic plating method, a thickness of, for example, By forming a 3.8 μm NiFe film to form the upper shield layer 26, the basic configuration of the dual spin valve element is completed.

In this case, the read gap d is the distance between the lower shield layer 13 and the upper shield layer 26 at the position where the thinned portion 22 and the NiFe raised portion 28 are provided. Therefore, d = 500 + 50 + 25 + 25 +
25 + 20 + 25 + 25 + 25 + 50 + 500 = 127
0 (Å), and the gap can be reduced by about 24% as compared with 1670 ° where the thinned portion 22 and the NiFe raised portion 28 are not provided.

Also in this case, the PdPtMn antiferromagnetic layer 2
In the case where the thinned portion 22 is provided in the 0 reading region, the direct magnetization direction fixing force of the region corresponding to the thinned portion 22 of the CoFe pinned layer 19 is weakened, but a sufficient thickness not involved in reading is obtained. The magnetization direction fixing force acting on both ends of the CoFe pinned layer 19 biased by both ends of the PdPtMn antiferromagnetic layer 20 having the above-mentioned structure compensates for the magnetization direction fixing force at the center of the CoFe pinned layer 19, and the CoFe pinned layer 32 Also, the magnetization direction fixing force acting on both ends of the CoFe pinned layer 32 biased by the PdPtMn thick portion 30 having a sufficient thickness which is not involved in the reading and fixing the magnetization direction at the center of the CoFe pinned layer 32 Since the force is also supplemented, the characteristics do not deteriorate.

Next, a modification of the first and second embodiments of the present invention will be described with reference to FIG. FIG. 6A is a modification of the first embodiment of the present invention. As shown in FIG. 6A, a spin valve provided with an antiferromagnetic material layer on the substrate side is used. In order to form such a structure, the NiFe raised portion 28 and the PdPtMn thick portion in FIGS. 3A and 3B in the second embodiment are required. The formation process of No. 30 may be used as it is, and the effect of narrowing the read gap obtained is the same as that of the first embodiment.

In the case of the modification of the first embodiment, the manufacturing process is more complicated than in the first embodiment.
Since the surface can be flattened, the upper shield layer 2
When an inductive head having the upper shield layer 26 as a lower magnetic pole layer is provided on 6 to form a composite magnetic head, patterning of the inductive head can be performed with high precision.

FIG. 6B shows a modification of the second embodiment of the present invention. As shown in FIG. 6B, the lower lead gap layer is not provided without the NiFe raised portion 28. After depositing the PdPtMn antiferromagnetic layer 35 having a thickness of, for example, 250 ° on the layer 14, the steps after the step of depositing the CoFe pinned layer 32 may be exactly the same as those in the second embodiment. Things.

In the case of the modification of the second embodiment, the manufacturing process is simplified as compared with the second embodiment.
The effect of narrowing the read gap is half that of the second embodiment.

Although not shown, when the thin portion is provided only on one of the PdPtMn antiferromagnetic layers constituting the dual spin valve element, the substrate side is opposite to the case of FIG. 6B. 4 may be provided in the PdPtMn antiferromagnetic layer provided in FIG.
After the formation up to the step (c), the lead electrode 24, the upper lead gap layer 25, and the upper shield layer 26 may be provided without providing the thinned portion 22.

Although the embodiments of the present invention have been described above, the present invention is not limited to the configurations described in the embodiments, and various modifications are possible. For example, in the description of each of the above embodiments, PdPtMn, which is a Mn-based ordered alloy type antiferromagnetic material, is used as the antiferromagnetic layer, but it is not necessarily a Mn-based ordered alloy type antiferromagnetic material. It is not necessary to use, for example, IrMn, which is a Mn-based disordered alloy type antiferromagnetic material. In this case, the crystal of the underlayer is formed so that the deposited IrMn has antiferromagnetic properties. The structure needs to be considered.

In each of the above embodiments, N
As iFe, CoFe, and PdPtMn, respectively,
Ni ₈₁ Fe ₁₉ , Co ₉₀ Fe ₁₀ , and Pd ₃₁ Pt ₁₇ Mn
_{Although 52} is used, the composition ratio is not limited to such a composition ratio, and the composition ratio may be appropriately selected according to required magnetic characteristics, processing characteristics, and the like.

In the above description of each embodiment of the present invention, an Al ₂ O ₃ —TiC substrate is used as a substrate, but a substrate such as a Si substrate or a glass substrate having a SiO ₂ film formed on the surface is used. May be used, and
As the ferromagnetic material and the antiferromagnetic material, a commonly used ferromagnetic material and antiferromagnetic material other than those described in the embodiment may be used.

In the description of the second embodiment, when the NiFe raised portion 28 is formed, the selective electrolytic plating method is used. However, the present invention is not limited to the selective electrolytic plating method. Alternatively, the convex structure may be formed by etching the periphery of the thicker lower shield layer by ion milling using Ar ions using a resist pattern as a mask.

In the description of the second embodiment, the PdPtMn thick portion 30 is formed by the lift-off method. However, the present invention is not limited to the lift-off method, and the PdPtMn film may be formed to have a substantially flat surface. It is formed as thick as possible, and is etched back or CMP (Chemical
The PdPtMn thin film portion having a thickness of about 50 ° may be left by stopping the etch-back or CMP process halfway.

[0056]

According to the present invention, the thickness of the portion corresponding to the reading region of the antiferromagnetic layer constituting the spin valve film is made thinner than the other portions, so that the magnetic characteristics are degraded. Without this, the effective read gap can be narrowed, thereby improving the positional resolution of the MR head using the magnetoresistive element, and consequently contributing to the spread of high-density HDD devices. large.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a basic configuration of the present invention.

FIG. 2 is an explanatory diagram of a manufacturing process of the spin valve element according to the first embodiment of the present invention up to a certain point.

FIG. 3 is an explanatory diagram of a manufacturing process of the spin valve element according to the first embodiment of the present invention after FIG. 2;

FIG. 4 is an explanatory diagram of a manufacturing process of a dual spin valve element according to a second embodiment of the present invention up to a certain point;

FIG. 5 is an explanatory diagram of a manufacturing process after FIG. 4 of the dual spin valve element according to the second embodiment of the present invention.

FIG. 6 is an explanatory diagram of a modification of the first and second embodiments of the present invention.

FIG. 7 is an explanatory diagram of a conventional spin valve element.

FIG. 8 is an explanatory diagram of a relationship between a read gap and a recording density.

[Explanation of symbols]

1 substrate 2 magnetic shielding layer 3 read gap layer 4 free layer 5 nonmagnetic layer 6 pinned layer 7 antiferromagnetic layer 8 thin portion 9 read gap layer 10 magnetic shielding layer 11 Al ₂ O ₃ -TiC substrate 12 Al ₂ O ₃ Film 13 Lower shield layer 14 Lower read gap layer 15 Ta film 16 NiFe free layer 17 CoFe free layer 18 Cu intermediate layer 19 CoFe pinned layer 20 PdPtMn antiferromagnetic layer 21 Resist pattern 22 Thinned portion 23 Resist pattern 24 Lead electrode Reference Signs List 25 upper read gap layer 26 upper shield layer 27 resist pattern 28 NiFe raised part 29 resist pattern 30 PdPtMn thick part 31 PdPtMn thin film part 32 CoFe pinned layer 33 Cu intermediate layer 34 free layer 35 PdPtMn antiferromagnetic layer 41 Al ₂ O ₃ —TiC substrate 42 Al ₂ O ₃ film 43 Lower shield layer 44 Lower read gap layer 45 Free layer 46 Cu intermediate layer 47 Pinned layer 48 Antiferromagnetic layer 49 Lead electrode 50 Upper read gap layer 51 Upper shield layer 52 Antiferromagnetic layer 53 Pinned layer 54 Cu intermediate layer 55 Magnetoresistive element 56 Magnetic recording medium 57 Recording bit

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Keiichi Nagasaka 4-1-1, Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Limited (72) Inventor Atsushi Tanaka 4-1-1, Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture No. 1 F-term in Fujitsu Limited (reference) 5D034 BA05 BA15 BB08 CA06 CA08 5E049 AA04 AA07 AA09 AC00 AC05 BA12 BA16 CB01 CC01 DB04 DB12 EB01 GC01

Claims (4)

[Claims] 1. An antiferromagnetic layer having at least one antiferromagnetic layer,
In a magnetoresistive element comprising a magnetoresistive film patterned into an arbitrary shape and magnetic shield layers provided above and below the magnetoresistive effect film via a read gap layer, the at least one antiferromagnetic material A magnetoresistive element, wherein a thin portion having a thickness different from that of another portion is provided in a part of the layer. 2. The magnetoresistive element according to claim 1, wherein the thin portion is provided in a portion related to signal reading of the magnetoresistive element. 3. The magneto-resistance effect film is formed by sequentially laminating a free layer composed of at least one magnetic film, a non-magnetic layer, a pinned layer composed of at least one magnetic film, and an antiferromagnetic layer. 3. The magnetoresistive element according to claim 2, wherein said magnetoresistive element has a structure. 4. The method according to claim 1, wherein the magnetoresistive film is an antiferromagnetic layer,
A pinned layer composed of at least one magnetic film, a nonmagnetic layer, a free layer composed of at least one magnetic film, a nonmagnetic layer, a pinned layer composed of at least one magnetic film, and an antiferromagnetic layer 3. The magnetoresistance effect element according to claim 2, wherein the magnetoresistance effect element has a laminated structure.