JPH08138216A - Magnetic head - Google Patents

Abstract

(57) [Abstract] [Problem] Shifting the operating point to the center of resistance change,
Ensures good linearity with respect to the signal magnetic field. A magnetic head includes a magnetic pinned layer, a magnetic rotation layer having an easy axis of magnetization in the head track width direction, and a magnetic stack including a non-magnetic layer interposed between the magnetic pinned layer and the magnetic rotation layer. And the signal magnetic field is almost zero.
The magnetization direction of the magnetization pinned film is inclined by less than 30 degrees from the head depth direction to the magnetization direction of the magnetization rotation layer so that the magnetization of the magnetization pinned layer and the magnetization of the magnetization rotation layer are orthogonal to each other.
Alternatively, a magnetic head using a magnetic field resistance effect film, wherein the easy axis of magnetization of the magnetization rotation layer is inclined from the head track width direction toward the magnetization direction of the magnetization pinned layer by less than 30 degrees.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head using a magnetoresistive effect film.

[0002]

2. Description of the Related Art To read a signal recorded on a magnetic recording medium, a method is widely known in which a read head having a coil is moved relative to the recording medium and the voltage induced in the coil by electromagnetic induction is detected. ing. On the other hand, a magnetoresistive head that utilizes a phenomenon in which the electric resistance of a certain type of ferromagnetic material changes according to the strength of an external magnetic field is also known as a high-sensitivity head that detects the signal magnetic field of a recording medium. (IEEE MAG-7,150, (1971)). In recent years, as the demand for a small-sized and large-capacity magnetic recording device has increased and the relative speed between the read head and the recording medium has decreased, the importance of a magnetoresistive head capable of producing a large output independent of the relative speed has increased. .

In the conventional magnetoresistive head, an 80at% Ni-20at% Fe alloy (abbreviated as permalloy) is generally used for the MR element portion whose resistance changes by sensing an external magnetic field. Permalloy has good soft magnetic properties, but has a maximum magnetoresistance change of 3%
A material exhibiting a magnetoresistance change with a higher sensitivity has been desired. In recent years, a huge magnetoresistance change has appeared in a multilayer film of a ferromagnetic metal layer such as Fe / Cr or Co / Cu called an artificial lattice type and a non-magnetic metal layer, and a maximum of 100%
A large rate of change in magnetoresistance exceeding 100 is also reported (Phy
s. Rev. Lett., Vol. 61, 2472 (1998) and Phys. Rev. Lett.,
Vol. 64, 2304 (1990)). Moreover, it was reported that the rate of change in magnetoresistance periodically oscillates in the absence of an external magnetic field when the thickness of the non-magnetic layer is changed. It is explained that it occurs because of ferromagnetic coupling. At this time, the electric resistance of the multilayer film is high in the antiferromagnetically coupled state in which the magnetic layers are antiparallel to each other, and is low in the ferromagnetically coupled state in which the magnetic layers are parallel to each other. Therefore, the magnetoresistance change is obtained by antiferromagnetically coupling in the absence of an external magnetic field, and by ferromagnetically coupling by applying an external magnetic field higher than the saturation magnetic field.

On the other hand, when the above-mentioned antiferromagnetic coupling state is used, the saturation magnetic field becomes large because the coupling force is large. Therefore, some methods have been reported that do not use the antiferromagnetic coupling state but utilize the difference in resistance between the parallel magnetization state and the antiparallel magnetization state. First, different coercive force
An example of realizing a magnetoresistance change by using two types of layers and making the magnetizations of both magnetic layers antiparallel to each other by utilizing this difference in coercive force (Journal of Applied Magnetics, Vol.15, No.5 813). (1991)), secondly, the magnetization is fixed by applying an exchange bias by the antiferromagnetic layer to one of the two ferromagnetic layers sandwiching the nonmagnetic layer, and the other ferromagnetic layer reverses the magnetization by an external magnetic field. By
This is an example of realizing a large magnetoresistance change by creating parallel and antiparallel states of the magnetizations of the ferromagnetic layers with the nonmagnetic layer sandwiched (Phys. Rev. B., Vol. 45806 (1992) and JA.
ppl.Phys., Vol.69,4774 (1991)). Particularly, in the spin-valve type magnetic layer, an element has been proposed in which the magnetization direction of the antiferromagnetic layer and the easy axis of the unfixed ferromagnetic layer are made orthogonal to each other and no operating point bias is required (Japanese Patent Laid-Open No. 4-35831).
0).

[0005]

As described above, some magnetoresistive effect elements using spin-dependent scattering have been proposed. However, when these magnetoresistive effect elements are processed into a rectangular pattern used in an actual magnetic head, the magnetization at the time of design is fixed between the magnetization fixed layer and the magnetization rotation layer (soft magnetic layer that rotates by the signal magnetic field). It becomes impossible to realize the orthogonal state and the operating point shift becomes large. As a result, the magnetization of the ferromagnetic layer that is not fixed to the medium magnetic field cannot respond, and good linearity cannot be obtained with respect to the signal magnetic field, resulting in a problem that the output is distorted.

The present invention has been made to address such a problem. By shifting the operating point to the center of resistance change, good linearity with respect to the signal magnetic field can be ensured. An object is to provide a magnetic head using a magnetoresistive film.

[0007]

A first magnetic head of the present invention is a magnetic pinned layer, a magnetic rotation layer having an easy axis of magnetization in the head track width direction, and a non-magnetic layer interposed between the magnetic pinned layer and the magnetic rotation layer. A magnetic head comprising a magnetic stack including a magnetic layer, wherein the magnetization direction of the magnetization pinned layer is perpendicular to the magnetization direction of the magnetization pinned layer so that the magnetization of the magnetization pinned layer is orthogonal to the magnetization of the magnetization pinned layer when the signal magnetic field is zero. Is inclined by less than 30 degrees toward the magnetization direction of the magnetization rotation layer.

A second magnetic head of the present invention is a magnetic laminated layer including a magnetization pinned layer having a magnetization direction in the head depth direction, a magnetization rotation layer, and a non-magnetic layer interposed between the magnetization rotation layer and the magnetization rotation layer. In a magnetic head including a body, when the signal magnetic field is 0, the magnetization easy axis of the magnetization fixed layer is perpendicular to the direction of the head track width so that the magnetization of the magnetization fixed layer and the magnetization of the magnetization fixed layer are orthogonal to each other. It is characterized by being inclined less than 30 degrees toward the magnetization direction.

A third magnetic head of the present invention has a magnetization pinned layer having a magnetization direction in the head depth direction, a magnetization rotation layer having an easy axis of magnetization in the head track width direction, and between the magnetization pinned layer and the magnetization rotation layer. A magnetic head comprising a magnetic laminated body including an intervening non-magnetic layer, wherein a product of saturation magnetization and volume of a magnetization pinned layer or a ferromagnetic layer pinned by this magnetization pinned layer is V ₁ , and a magnetization rotation layer. V ₂ / V ₁ ≧ 3, where V ₂ is the product of the saturation magnetization and the volume.

According to a fourth magnetic head of the present invention, a magnetization pinned layer having a magnetization direction in the head depth direction, a magnetization rotation layer having an easy axis of magnetization in the head track width direction, and between the magnetization pinned layer and the magnetization rotation layer. A magnetic head comprising a magnetic laminated body including an intervening non-magnetic layer, wherein a magnetic layer is laminated on the magnetic laminated body, and the direction of magnetization of the magnetic layer is approximately antiparallel to the direction of magnetization of the magnetization pinned layer. It is characterized in that the magnetization of the magnetization pinned layer and that of the magnetization rotation layer are substantially perpendicular to each other by being magnetostatically coupled to the magnetization pinned film so that

A fifth magnetic head of the present invention is a magnetization rotation film formed on a ferromagnetic underlayer, the magnetization of which is rotated by a signal magnetic field. Here, the signal magnetic field is approximately 0 and the magnetization is oriented in the track width direction. The magnetization pinned film whose magnetization does not substantially move in the signal magnetic field, the magnetization is pinned in the signal magnetic field inflow direction, and the non-magnetic film interposed between the magnetization rotation film and the magnetization pinned film And a pair of magnetoresistive effect elements using spin-dependent scattering and a pair of magnetic field rotating films formed directly below the surface of the ferromagnetic underlayer on both sides of the magnetic field rotating film, which are separated from the portions that rotate in response to a signal magnetic field from a recording track. Bias film (hard film, etc.) and the magnetoresistive element
It is characterized in that it is composed of electrodes for supplying a sense current to the child .

The above-mentioned first to fifth magnetic heads will be described in more detail below.

The basic structure is a laminated body of a magnetization rotation layer / a non-magnetic layer / a magnetization fixed layer. The film thicknesses are preferably 0.5 to 20 nm, 0.5 to 10 nm, and 0.5 to 20 nm, respectively. Further, a plurality of laminated bodies may be used, or each layer may be composed of a plurality of layers.

First, when the magnetoresistive effect element is processed into a rectangular pattern used in an actual magnetic head, the orthogonal state of the magnetization at the time of design is formed between the two layers of the magnetization fixed layer and the magnetization rotation layer. The phenomenon that the operating point cannot be maintained and the operating point shifts will be described. As the energy of the two-layer film,
Consider anisotropic energy, magnetostatic energy, interlayer exchange coupling energy, self-demagnetization energy, and interlayer magnetostatic coupling energy. One of the two-layer films is M ₁ and the other is M _2, and the angles formed by the magnetization directions of M ₁ and M ₂ with respect to the longitudinal direction of the rectangular pattern are θ ₁ , θ ₂ and M, respectively.
_The direction of the easy axis of the magnetization of ₂ is set as shown in FIG. Here, the longitudinal direction of the rectangular pattern represents the head track width direction. At this time, it is assumed that M ₁ is fixed and the magnetization does not move (that is, θ ₁ = 90 °). Again 2
The layer thicknesses of the layer films M ₁ and M ₂ are t ₁ and t ₂ , respectively. When the sum of these energies is minimized, the magnetization angle θ ₂ of the layer (M ₂ ) where the magnetization is not fixed is represented by the following equation (1). Here, H _ex is the applied magnetic field, H _in is the exchange coupling magnetic field between layers, Hd ₁ is the demagnetizing field of the pinned layer, Hd ₂ is the demagnetizing field of the magnetization rotating layer, and Ku is the induced magnetic anisotropy energy of the magnetization rotating layer. , Ms is the saturation magnetization amount of the layer that rotates in magnetization.

[0015]

[Equation 1] Further, the resistance value R of the giant magnetoresistive effect is expressed by the following equation (2). Here, R ₀ represents the resistance value when the magnetizations of M ₁ and M ₂ are orthogonal, and ΔR represents the maximum resistance change amount. Here, it is assumed that the magnetization of the pinned layer (the ferromagnetic layer whose magnetization is pinned by the FeMn layer or the high coercive force layer) does not move.

[0016]

[Equation 2] FIG. 2 shows the H _ex dependency of R obtained by substituting the equation (1) into the equation (2). Here, H _in −H d ₁ has a negative value if the element has a normal rectangular shape, and therefore the operating point of the RH curve shifts as shown in FIG. This shift is H _ex = 0.
Then, θ ₂ deviates from 0, that is, the magnetization direction relationship between the magnetization pinned layer and the magnetization rotation layer deviates from the orthogonality. For example, the element shape is a rectangular shape of 3 × 80 μm,
When the layer thickness is 5 nm, H _in = 400 A / m, Hd ₁ = 2000 A / m
Therefore, H _in −Hd ₁ = −1600 A / m.

Therefore, in the magnetic head of the present invention, the shift of the operating point due to magnetostatic coupling is suppressed, or the magnetization direction of the magnetization pinned layer and the magnetization direction of the magnetization rotation layer are set when the energy such as magnetostatic coupling or demagnetizing field is stabilized. The angles are substantially orthogonal (ie, θ ₂
= 0) It is characterized by using a magnetoresistive effect layer.

The head depth direction according to the present invention is substantially an inflow direction of a signal magnetic field, and is indicated by an arrow direction X in FIG. The head track width direction is also indicated by the arrow direction Y.

The magnetization state when the magnetization direction of the magnetization pinned layer is tilted is shown below by a simple calculation formula, ignoring the magnetostatic coupling from the pinned layer. The specific resistance value ρ of the giant magnetoresistive effect is expressed by the following equation (3). Where ρ ₀ is the resistivity value when the magnetizations are orthogonal, Δρ is the maximum resistivity change,
θ ₁ is the magnetization angle of the pinned layer (the ferromagnetic layer pinned by the FeMn layer or the high coercive force layer), and θ ₂ is the magnetization angle of the soft magnetic layer, which are set as shown in FIG.

[0020]

(Equation 3) Further, the magnetization rotation of the soft magnetic layer is uniform magnetization rotation, and the magnetization M _{2 at} this time is expressed by the following equation (4). Here, Hk is an anisotropic magnetic field, which includes a demagnetizing field due to the anisotropy and shape of the film.

[0021]

[Equation 4] From these equations, the change rate ρ ′ of the specific resistance is expressed by the following equation (5).

[0022]

(Equation 5) From this equation, H of ρ'at each θ ₁ (inclination of the fixed layer)
Fig. 3 shows the change due to (here, Hk (including demagnetizing field)
Is about 6000 A / m). As shown in FIG. 3, the magnetization of the pinned layer is appropriately tilted so that the orthogonal magnetization condition of the pinned layer and the magnetization rotation layer (in FIG. 3, the change rate of the specific resistance is 0) means that the positive magnetic field side is high (high). You can see that it shifts to the resistance side. Therefore, the applied magnetic field is set to the orthogonal magnetization condition shifted to the negative magnetic field side due to the influence of the magnetostatic coupling from the pinned layer shown in FIG.
It can be returned to the 0 side. As a result, high sensitivity due to the giant magnetoresistive effect and excellent linear response to the signal magnetic field can be obtained. Such an effect can be obtained even when the magnetization direction of the magnetization rotation layer is inclined less than 30 degrees from the head track width direction toward the magnetization direction of the magnetization pinned layer as shown in the second magnetic head of the present invention. You can In the present invention, the magnetization pinned layer is preferably a ferromagnetic layer or a high coercive force layer or a laminated film of a high coercive force layer and a ferromagnetic layer, the magnetization of which is pinned by the exchange bias of the antiferromagnetic layer. In addition, the magnetization fixing method is preferably performed by heat-treating at a temperature of, for example, 150 to 200 ° C. while applying a magnetic field after the element is manufactured.

In the third magnetic head of the present invention, the product of the saturation magnetization and volume of the magnetization pinned layer or the ferromagnetic layer pinned by this magnetization pinned layer is V ₁ , and the saturation magnetization and volume of the magnetization rotation layer are When the product is V ₂ , the operating point shift is controlled by setting V ₂ / V ₁ ≧ 3. The reason will be described below. In the above formula (1), the applied magnetic field is
0 (that is, when H _{ex is} almost 0), and when the inter-layer exchange coupling magnetic field can be ignored (that is, H _{in is} almost 0).
, And the induced magnetic anisotropy energy, that is, the anisotropic magnetic field (2 Ku / Ms) is about 800 A / m, θ ₂
In order to be 0 to less than 30 degrees, it follows that t ₂ / t ₁ ≧ 3. Generally, in a magnetoresistive element, the magnetization pinned layer and the magnetization rotation layer often have the same planar shape. Therefore, when the layer thickness of the magnetization pinned layer is t ₁ and the layer thickness of the magnetization rotation layer is t _2. , And the volumes of the magnetization pinned layer and the magnetization rotation layer can be replaced by t ₁ and t ₂ . θ
_In order to make the range of ₂ more preferable, the more preferable range of V ₂ / V ₁ ratio is 3.5 times or more. Furthermore, the free layer has a multilayer structure in which a high resistance magnetic layer (Co-based amorphous alloy, NiFeCr alloy, etc.) is laminated on the opposite side in contact with the non-magnetic layer, so that even if the free layer thickness increases, ΔR / R It is possible to suppress the deterioration and enable highly sensitive reproduction.

In the third magnetic head, when the magnetization pinned layer is a laminated film of an antiferromagnetic layer and a ferromagnetic layer, V ₁ is the saturation magnetization × volume of the ferromagnetic layer pinned by this antiferromagnetic layer. When the magnetization fixed layer is a laminated film of a high coercive force layer and a ferromagnetic layer, the total magnetization x volume of the ferromagnetic layer and the high coercive force layer fixed by the high coercive force layer is obtained. In order to control the operating point shift in this way, a method of changing the layer thickness of the ferromagnetic layer whose magnetization direction is fixed and the layer thickness of the magnetization rotation layer,
There is a method of inclining the magnetization direction of the magnetization fixed layer, and each of them can be used independently. Furthermore, if both are used in combination, even better results are obtained.

In the fourth magnetic head of the present invention, another magnetic layer is laminated on the magnetization pinned layer or the magnetization rotation layer, preferably via a non-magnetic layer, and the direction of magnetization of this magnetic layer is set to the magnetization of the magnetization pinned layer. By substantially antiparallel to the direction of, the magnetization of the magnetization pinned layer and the magnetization rotation layer can be made substantially orthogonal at a signal magnetic field of 0, and the operating point shift can be improved. This is because the magnetostatic coupling between the pinned layer and another magnetic layer (the leakage magnetic field from the pinned layer is absorbed by another magnetic layer) weakens the magnetostatic coupling between the pinned layer and the magnetization rotation layer. The other magnetic layer may be a hard film magnetized in a direction opposite to the magnetization direction of the pinned layer, or a soft film whose magnetization direction is easily changed by a leakage magnetic field from the pinned layer. good. In order to suppress the shunting of the sense current (when the sense current is shunted, the rate of change in resistance decreases), it is desirable that the other magnetic layer have a resistance as high as possible.

With the above-mentioned first to fourth structures, the magnetization direction of the magnetization pinned layer and the magnetization direction of the magnetization rotation layer can be made substantially orthogonal to each other.

With such a structure, the shift of the operating point that occurs when the magnetoresistive effect element is processed can be alleviated, and the operating point can be shifted to the center of the resistance change. As a result, a high resistance change rate can be effectively utilized, and good linearity can be obtained with respect to the signal magnetic field. Therefore, an excellent magnetic head having high sensitivity and high frequency can be manufactured.

A fifth magnetic head of the present invention is a magnetization rotating film, whose magnetization is rotated by a signal magnetic field formed on a ferromagnetic underlayer, a magnetization fixed film whose magnetization does not substantially move in the signal magnetic field, and a magnetization. A magnetoresistive effect element utilizing spin-dependent scattering composed of a non-magnetic film sandwiched between a rotating film and a magnetically pinned film, and a part of the magnetically rotating film which is magnetized and rotated in response to a signal magnetic field from a recording track. It is composed of a pair of bias films (hard films or the like) formed on both sides immediately below the surface of the ferromagnetic underlayer, and electrodes for supplying a sense current to the magnetoresistive film.

In the conventional spin valve GMR head, a longitudinal bias magnetic field was applied to the magnetization rotation layer by hard films arranged close to both ends of the spin valve film in order to suppress Barkhausen noise. (For example
(USP5079035) Since the hard film is formed by lift-off with the resist used when patterning the spin valve film by Ar ion milling, the hard film attached to the resist taper is likely to remain at the spin valve end, and the insulation between the shield and the spin valve is poor. Is likely to occur, and it will be difficult to narrow the gap, which is essential for increasing the linear recording density in the future. In addition, since the stray magnetic field of the hard film adversely affects the spin valve film,
If the track width is reduced to 2 μm or less, the sensitivity will decrease.

On the other hand, in the present invention, the spin valve pattern can be produced by the ordinary film formation, photolithography, etching and resist removal after the hard film pattern is formed by ordinary film formation, photolithography, etching and resist removal. The above-mentioned insulation failure is unlikely to occur. In addition, by increasing the distance between the hard films as compared with the electrode distance that defines the reproduction track width, the leakage magnetic field from the hard film does not flow into the magnetic sensitive part (between the electrodes) of the spin valve part. Therefore, it is possible to prevent a decrease in sensitivity during narrow track reproduction.

Specifically, the thickness of the gap film is 0.15 μm.
In the following, if the hard film gap is expanded by 1 μm or more than the electrode gap, even if the electrode gap is as narrow as 1 μm, the sensitivity degradation due to the hard film leakage magnetic field can be significantly reduced.

In the conventional MR head using the anisotropic magnetoresistive effect, crosstalk from adjacent tracks becomes a problem when the hard film spacing is made wider than the electrode spacing, but the magnetization of the magnetization rotation layer is orthogonal to the medium magnetic field. Direction (track width direction)
By aligning with, it is possible to prevent not only the operating point shift but also crosstalk. In addition, since the conventional spin valve film uses a non-magnetic underlayer such as Ta, the Ta underlayer interferes with the magnetic coupling between the hard film and the magnetization rotation layer, making it difficult to suppress Barkhausen noise. However, such a problem does not occur in the spin valve film of the present invention using the ferromagnetic underlayer.

As the ferromagnetic base film, a Co type amorphous film or the like for improving the smoothness of the metal film thereon and fcc (1
11) NiFe, which is an fcc-based magnetic film that promotes orientation
A magnetic laminated structure such as NiFeCr or NiFeCr is desirable. As a result of the warpage, fcc (1
11) Good soft magnetism of the Co-based film due to orientation can be realized.

Further, a Co type alloy used for the magnetization rotation layer,
Since Cu used for the non-magnetic film, Co or Co-based alloy used for the magnetization pinned film, and FeMn antiferromagnetic bias film used for pinning the magnetization of the magnetization pinned film do not necessarily have sufficient corrosion resistance, the magnetization rotation film, Part or all of the magnetic pinned film including the magnetic film and bias film recedes backward from the medium facing surface compared to the magnetic underlayer film and hard film of the head (recess).
Therefore, it is desirable that the slider is not exposed directly to the outside during processing. In this recess configuration, the longitudinal biasing bias film is present up to the vicinity of the medium facing surface like the magnetic underlayer film, and thus Barkhausen noise of the magnetic underlayer and the magnetization rotation layer of the spin valve film can be suppressed.

[0035]

BEST MODE FOR CARRYING OUT THE INVENTION

[0036]

Embodiments of the present invention will be described below with reference to the drawings. Example 1 In this example, a case in which the layer thickness of a ferromagnetic layer having a magnetization fixed layer and the layer thickness of a magnetization rotation layer are changed will be described. Spin-valve MR element with high coercive force layer 2 at the end 100 μm
× 5 μm was formed on the substrate 4, processed into a rectangular shape, and then C
u A lead 3 having a thickness of about 200 nm was formed. Figure 4 is a plan view
FIG. 4B is a sectional view taken along line AA and FIG. The spin valve laminated film 1 has a lower ferromagnetic layer (CoFe) 11 on the supporting substrate 4.
15 nm, intermediate layer (Cu) 12 3 nm, upper ferromagnetic layer (CoF
e) 13 is 5 nm, antiferromagnetic layer (FeMn) 14 is 8 nm,
A protective layer (Ti) 15 having a thickness of 10 nm was laminated in that order. The high coercive force layer 2 is formed of CoPt with a thickness of about 40 nm and is magnetized as shown in FIG.
It was magnetized in the direction shown in. In this case, V ₂ / V ₁ = 3.

The resistance value-applied magnetic field curve (hereinafter referred to as RH curve) of the obtained magnetic head is shown in FIG. The shift was significantly eased as compared with the RH curve of Comparative Example 1 (FIG. 9) described later. Therefore, even when a negative signal magnetic field is applied, a resistance change can be obtained as compared with FIG.

In the present invention, examples of the material of the intermediate layer 12 include Cu, Au, Ag, and alloys containing these as main components. As the material of the antiferromagnetic layer 14, in addition to FeMn, NiMn, CoMn, PtMn,
An antiferromagnetic alloy such as PdMn may be used. As the material of the protective layer 15, W, Mo, Cr, Nb, Ta or the like can be used in addition to Ti.

For the magnetization rotation layer and the magnetization pinned layer, a ferromagnetic material containing Co, Fe, Ni or the like can be used, and particularly Co _1-x Fe _x (0 <x ≤ 0.4 at) is used. Alloys are preferred. Furthermore, Pd, Cu, Au, A
It does not matter if g, Ir, Rh, etc. are added.

Example 2 In this example, the case where the layer thickness of the ferromagnetic layer having the magnetization pinned layer and the layer thickness of the magnetization rotation layer are changed and the magnetization direction of the magnetization pinned layer is further tilted will be described. To do. As shown in FIG. 7, a magnetic head having the same configuration as in Example 1 was obtained except that the magnetization direction of the antiferromagnetic layer (FeMn) 14 was inclined 20 degrees toward the magnetization direction of the high coercive force layer 2.

The RH curve of the obtained magnetic head is shown in FIG.
Shown in Compared to FIG. 6, the shift of the RH curve was further alleviated. Therefore, even when a strong negative signal magnetic field invades, the high resistance change rate, which is a characteristic of the giant magnetoresistive effect, can be fully utilized and the output is not distorted.

Example 3 In this example, the case where the magnetization direction of the magnetization fixed layer is inclined will be described. A magnetic head having the same configuration as in Example 2 was obtained except that the lower ferromagnetic layer (CoFe) 11 had a thickness of 5 nm.
The shift of the RH curve of the obtained magnetic head is shown in Example 1.
And an almost intermediate value between Example 2 and Example 2.

Comparative Example 1 A magnetic head having the same structure as in Example 1 except that the lower ferromagnetic layer (CoFe) 11 was 5 nm was obtained. The RH curve of the obtained magnetic head is shown in FIG. As shown in FIG. 9, the R-H curve shifts greatly and the applied magnetic field (H) is 0
At the time of, it can be seen that the resistance is increased, that is, the magnetization is antiparallel. Since this magnetic field is the signal magnetic field from the medium, almost no resistance change is obtained when a negative signal magnetic field is applied. in this way,
The layer thickness of the ferromagnetic layer (the upper ferromagnetic layer in this comparative example) fixed by the magnetization pinned layer (the antiferromagnetic layer in this comparative example) and the layer of the magnetization rotation layer (lower ferromagnetic layer in this comparative example) Equal thickness,
Furthermore, when the magnetization direction of the antiferromagnetic layer is not tilted,
The RH curve shifts significantly.

Comparative Example 2 The same structure as in Example 2 was used except that the magnetization direction of the antiferromagnetic layer (FeMn) was tilted by 20 degrees to the side opposite to the magnetization direction of the high coercive force layer 2 as shown in FIG. A magnetic head having the above was obtained. The RH curve of the obtained magnetic head is shown in FIG. FIG.
As shown in FIG. 1, the shift of the RH curve is promoted as compared with FIG. 8, and the magnetizations of both ferromagnetic layers are almost antiparallel in the magnetic field 0, and the response of the magnetization to the negative signal magnetic field is increased. There was nothing at all, and the linearity of the RH curve was distorted.

The tilt angle of the magnetization direction of these magnetization pinned layers and the layer thickness ratio of each ferromagnetic layer depend on the element shape, the saturation magnetization amount of each magnetic layer, the anisotropic magnetic field, etc. When the inclination angle of the magnetization direction of the pinned layer is less than 30 degrees, the layer thicknesses of the magnetization pinned layer and the magnetization rotation layer are t ₁ and t ₂ , and the saturation magnetization amounts are M ₁ and M ₂ , respectively, t ₂ · M ₂ / t ₁
・ By setting M ₁ ≧ 3, the shift of the RH curve can be significantly alleviated. Therefore, the high resistance change rate can be fully utilized.

Example 4 The lower ferromagnetic layer 11 was formed of CoFe (5 nm) / CoZrNb (5
nm) and the upper ferromagnetic layer (CoFe) 13 is 3 nm
A magnetic head having the same structure as in Example 1 except that the thickness was Here, V ₂ / V _1b = 3.1.

The RH curve of the obtained magnetic head is shown in FIG.
It is shown in FIG. As shown in FIG. 12, the operating point was near the center of the RH curve, and the shift was significantly eased. As shown in this embodiment, good results can be obtained even when the lower magnetic layer is a laminated film of ferromagnetic layers.

Although the antiferromagnetic layer is used in this embodiment to fix the magnetization direction of the ferromagnetic layer, a high coercive force layer such as CoPt or CoNi may be used instead of the antiferromagnetic layer. it can. In that case, the product (V _1a ) of the layer thickness of the high coercive force layer and the ferromagnetic layer fixed thereto and the saturation magnetization amount.
And the ratio of the product (V ₂ ) of the layer thickness of the magnetization rotation layer to the saturation magnetization amount must be V ₂ / V _1a ≧ 3. When the laminated film of the high coercive force layer / ferromagnetic layer is a high coercive force layer single layer film, the product of the layer thickness of the high coercive force layer and the saturation magnetization amount (V
_1b ) and the product of the layer thickness of the magnetization rotation layer and the saturation magnetization (V ₂ ).
It is necessary to set the ratio to V ₂ / V _1b ≧ 3.

Further, even when the high coercive force layer is used instead of the antiferromagnetic layer in this way, by tilting the magnetization direction, the same effects as those of the second and third embodiments can be obtained.
However, as shown in FIG. 3, the RH curve becomes distorted as the tilting angle increases. At this time, when the actual head is manufactured, the magnitude of the second-order distortion of the reproduced signal is -20d.
In order to be able to suppress it to around B,
It must be less than 30 degrees, that is, 0 degrees <θ ₁ <70 degrees. The angle can be appropriately determined based on the relationship between V _1a and V _2, etc., but it is preferable that the angle is substantially 1 to 25 degrees.

Embodiment 5 In this embodiment, in addition to the case where the layer thickness of the ferromagnetic layer having the magnetization pinned layer and the layer thickness of the magnetization rotation layer are changed, the magnetization direction of the magnetization rotation layer (direction of easy axis of magnetization) is further added. The case of tilting will be described.

A magnetic head having the same structure as in Example 1 and having the magnetization (easy axis) direction of the magnetization rotation layer inclined was manufactured.
The magnetization direction (easy axis) of the magnetization rotation layer is either 200 nm in the bias magnetic field, or 200 nm in the magnetic field after film formation or after device fabrication.
It can be tilted by performing heat treatment at a temperature of up to 300 ° C. Therefore, at the time of film formation, as shown in FIG. 13, a bias magnetic field is applied by tilting the antiferromagnetic layer (FeMn) by 20 degrees, or by tilting the antiferromagnetic layer (FeMn) by 20 degrees. By performing heat treatment while applying a bias magnetic field, the magnetization direction (easy axis) can be tilted.
These two methods can also be used simultaneously. At this time, the film formation in the bias magnetic field may be performed similarly to the upper and lower ferromagnetic layers of the spin valve laminated film, or the magnetization direction (easy axis) may be inclined only in the magnetization rotation layer. With such a structure, the shift of the RH curve can be alleviated. Example 6 In this example, a case where the magnetization direction of the longitudinal bias is further tilted in addition to the case where the layer thickness of the ferromagnetic layer having the magnetization fixed layer and the layer thickness of the magnetization rotation layer are changed will be described. A magnetic head having the same structure as in Example 1 and having the magnetization direction of the magnetization rotation layer tilted was manufactured. The high coercive force layer can be magnetized by applying a magnetic field from the outside after manufacturing the element. The magnitude of the magnetic field applied from the outside must be sufficiently larger than the coercive force of the high coercive force layer. Since the coercive force of the high coercive force layer used in this example was about 80 kA / m (1 kOe), the magnetization was 240 kA / m.
A magnetic field of (3 KOe) was applied to perform this. At this time, as in Example 5, the magnetic field application direction was tilted by 20 degrees to the magnetization direction of the antiferromagnetic layer (FeMn), thereby tilting the magnetization direction of the high coercive force layer.

With such a structure, the shift of the RH curve can be alleviated. Example 7 Examples 7 to 16 and Comparative Example 3 describe the case where magnetic layers are stacked with a non-magnetic layer in between. A plan view of the magnetic head of Example 7 is shown in FIG. 14 (a), and a sectional view taken along the line AA is shown in FIG. 14 (b). A high coercive force layer (CoPt) 2 having a thickness of 5 nm is formed on the supporting substrate 4, and a nonmagnetic layer (SiO ₂ ) 5
Was formed to a thickness of 2 nm, and then a spin valve laminated film 1 was produced. The spin-valve laminated film 1 includes a lower ferromagnetic layer (CoFe) 11 5
nm, intermediate layer (Cu) 12 is 3 nm, upper ferromagnetic layer (CoF
e) 13 is 5 nm, antiferromagnetic layer (FeMn) 14 is 8 nm,
A protective layer (Ti) 15 having a thickness of 10 nm was laminated in that order. This laminated film is processed into a rectangular shape as shown in FIG.
A lead 3 made of Cu about 200 nm was formed to obtain a magnetic head. The magnetization of the high coercive force layer 2 and the upper ferromagnetic layer 13, which is the pinned layer, was magnetized in the direction shown in FIG. The easy axis of magnetization of the lower ferromagnetic layer 11, which is the magnetization rotation layer, is given in the direction of the arrow in the figure. Here, the symbols ○, ×, → represent the direction of magnetization,
The symbol O indicates that the magnetization is from the back to the front of the paper, the symbol X indicates that the magnetization is from the front to the back of the paper, and the symbol → indicates that the magnetization is from the left to the right. The same symbols are used in the following examples.

The RH curve of the obtained magnetic head is shown in FIG.
5 shows. RH curve of Comparative Example 3 described later (FIG. 17)
The shift was significantly eased compared to. Therefore, even when a positive signal magnetic field is applied, a sufficient resistance change can be obtained as compared with FIG.

Although SiO ₂ is used as the non-magnetic layer 5 in this embodiment, Al ₂ O ₃ or the like may be used. Thus, it is desirable to use a non-conductive layer as the non-magnetic layer. For example, if a conductive layer such as Cu is used, the sense current is shunted and the rate of change in resistance is reduced.

The magnetization direction of the high coercive force layer 2 is preferably the element width direction (head depth direction) and the direction opposite to the magnetization direction of the antiferromagnetic layer. However, it may have a component in the element longitudinal direction (head track width direction).

The bias layer in this embodiment is determined by the saturation magnetization × volume with the magnetization pinned layer (CoFe). Therefore, the operating point shift is, for example, when the saturation magnetization × volume of the magnetization pinned layer is larger than the saturation magnetization × volume of the bias layer,
When they are equal as in this embodiment, they are almost in the middle (however, depending on the distance between the bias layer and the magnetization pinned layer (nonmagnetic layer thickness, etc.)). The operating point shift amount can be controlled by the saturation magnetization and the volume.

Comparative Example 3 A magnetic head having the same structure as in Example 7 except that the spin valve laminated film 1 was formed without forming a high coercive force layer (CoPt) and a nonmagnetic layer on the supporting substrate 4. Obtained. A cross-sectional view of the magnetic head is shown in FIG. The RH curve of the obtained magnetic head is shown in FIG. As shown in FIG. 17, it can be seen that the R-H curve is largely shifted, and when the applied magnetic field (H) is 0, the resistance is increased, that is, the magnetization is antiparallel. Since this magnetic field becomes a signal magnetic field from the medium, almost no resistance change is obtained when a positive signal magnetic field is applied.

Example 8 A magnetic head having the same structure as in Example 7 except that the film thickness of the high coercive force layer (CoPt) 2 was 2.5 nm was obtained.
The RH curve of the obtained magnetic head is shown in FIG. As shown in FIG. 18, the RH curve has a slight shift to the high resistance side, but the shift of the RH curve is moderated.

Example 9 A magnetic head having the same structure as in Example 7 except that the film thickness of the high coercive force layer (CoPt) 2 was set to 10 nm was obtained.
The RH curve of the obtained magnetic head is shown in FIG. As shown in FIG. 19, the shift of the RH curve was on the contrary to the low resistance side.

Example 10 A spin valve laminated film 1 was formed on a supporting substrate 4, and a nonmagnetic layer (SiO ₂ or TiN) 5 was formed thereon to a thickness of 2 nm.
A high coercive force layer (CoPt) 2 having a thickness of 5 nm was formed. The structure of the spin valve laminated film 1 is the same as that of the seventh embodiment except that the protective layer 15 is not laminated. This laminated film 1 was processed into the same rectangular shape as in Example 7, and leads 3 made of Cu about 200 nm were formed to obtain a magnetic head. A cross section of the magnetic head is shown in FIG.
The high coercive force layer 2, the upper ferromagnetic layer 13 and the lower ferromagnetic layer 11 were magnetized in the directions shown in FIG.

The RH curve of the obtained magnetic head was almost equal to that in FIG. Therefore, even when a positive signal magnetic field is applied, a sufficient resistance change can be obtained. The magnetization direction of the high coercive force layer 2 is preferably the element width direction (head depth direction) and the direction opposite to the magnetization direction of the antiferromagnetic layer. However, it may have a component in the element longitudinal direction (head track width direction).

Example 11 An antiferromagnetic layer (FeMn) 14 having a thickness of 8 nm, a ferromagnetic layer (NiFe) 16 having a thickness of 8 nm, and a nonmagnetic layer (SiO ₂ ) were formed on a supporting substrate 4.
5 was sequentially formed in a thickness of 2 nm, and a spin valve laminated film 1 was formed thereon. The structure of the spin valve laminated film 1 is the same as that of the seventh embodiment. This laminated film 1 was processed into the same rectangular shape as in Example 7, and leads 3 made of Cu about 200 nm were formed to obtain a magnetic head. FIG. 21 shows a cross section of the magnetic head. The ferromagnetic layer 16, the upper ferromagnetic layer 13, and the lower ferromagnetic layer 11 were magnetized in the directions shown in FIG.

The RH curve of the obtained magnetic head was almost equal to that shown in FIG. Therefore, even when a positive signal magnetic field is applied, a sufficient resistance change can be obtained.

The magnetization directions of the two ferromagnetic films fixed by the two antiferromagnetic layers are preferably antiparallel to each other in the element width direction (head depth direction).

Further, the magnetization of the antiferromagnetic layer has a different blocking temperature depending on whether the ferromagnetic layer whose magnetization is fixed is NiFe or CoFe.
After heat treatment of e / FeMn in a magnetic field, NiFe /
When magnetizing FeMn, the magnetic field heat treatment may be performed by changing the applied magnetic field direction. In addition, the bias layer (NiFe / FeM
n) and the magnetization pinned layer (CoFe / FeMn) have a relationship of saturation magnetization × volume as described in Example 7, and thus the operating point shift amount can be controlled by the saturation magnetization and volume.

Example 12 A CoZrNb layer 17 having a thickness of 5 nm and a nonmagnetic layer (SiO ₂ ) 5 having a thickness of 2 nm were sequentially formed on a supporting substrate 4, and then a spin valve laminated film 1 was formed thereon. The structure of the spin valve laminated film 1 is the same as that of the seventh embodiment. This laminated film 1 was processed into the same rectangular shape as in Example 7, and leads 3 made of Cu about 200 nm were formed to obtain a magnetic head. A cross section of the magnetic head is shown in FIG.

The RH curve of the obtained magnetic head is shown in FIG.
3 shows. The shift was moderated as compared with the RH curve of Comparative Example 3 (FIG. 17). This is because the magnetization of the CoZrNb layer 17 was rotated so that the magnetization was antiparallel to the magnetization of the pinned layer, so that the leakage magnetic field from the pinned layer was hard to be applied to the magnetization rotating layer. Therefore, even when a positive signal magnetic field is applied, a sufficient resistance change can be obtained as compared with FIG. Further, the easy axis direction of the CoZrNb layer may be the element width direction (head depth direction) or the element longitudinal direction (head track width direction).

Example 13 A spin valve laminated film 1 was formed on a supporting substrate 4, a nonmagnetic layer (SiO ₂ or TiN) 5 was formed thereon to a thickness of 2 nm, and
The CoZrNb layer 17 was formed to a thickness of 5 nm. The structure of the spin valve laminated film 1 is the same as that of the seventh embodiment except that the protective layer 15 is not laminated. This laminated film 1 was processed into the same rectangular shape as in Example 7, and leads 3 made of Cu about 200 nm were formed to obtain a magnetic head. A cross section of the magnetic head is shown in FIG.

The RH curve of the obtained magnetic head was almost equal to that shown in FIG. Therefore, even when a positive signal magnetic field is applied, a sufficient resistance change can be obtained. In this case, since the antiferromagnetic layer 14 of the spin valve laminated film 1 and the CoZrNb layer 17 are not magnetically coupled to each other, almost the same characteristics can be obtained with the magnetic head having the same structure except that the nonmagnetic layer 5 is not formed. Was given.

Example 14 A CoZrNb layer having a thickness of 10 nm was formed on a supporting substrate 4 and oxygen was added to the substrate.
% Atmosphere, heat treatment at a temperature of 200 ℃, CoZr
An oxide layer 18 of about 5 nm is formed on the surface of the Nb layer. The same spin valve laminated film 1 as in Example 7 was formed on this.
This laminated film 1 was processed into the same rectangular shape as in Example 7, and Cu
A lead 3 having a thickness of about 200 nm was formed to obtain a magnetic head. A cross section of the magnetic head is shown in FIG. The CoZrNb layer 17, the upper ferromagnetic layer 13, and the lower ferromagnetic layer 11 were magnetized in the directions shown in FIG.

The RH curve of the obtained magnetic head was almost equal to that in FIG. Therefore, even when a positive signal magnetic field is applied, a sufficient resistance change can be obtained.

Example 15 A lower ferromagnetic layer (CoFe) 11 having a thickness of 5 nm, an intermediate layer (Cu) 12a having a thickness of 3 nm, and an upper ferromagnetic layer (CoFe) 1 are formed on a supporting substrate 4.
3 is formed to a thickness of 5 nm, and the intermediate layer (Cu) 12b is formed on the layer to 1 n.
m, a ferromagnetic layer (CoFe) 13a having a thickness of 5 nm, and an antiferromagnetic layer (FeMn) 14 having a thickness of 8 nm are sequentially formed to form a protective layer (Ti).
15 were laminated. This laminated film was processed into the same rectangular shape as in Example 7, and the lead 3 made of Cu about 200 nm was formed to obtain a magnetic head. FIG. 26 shows a cross section of the magnetic head. The lower ferromagnetic layer 11, the upper ferromagnetic layer 13, and the ferromagnetic layer 13a were magnetized in the directions shown in FIG.

The RH curve of the obtained magnetic head was almost equal to that in FIG. Therefore, even when a positive signal magnetic field is applied, a sufficient resistance change can be obtained. In this embodiment, the layer driven by the signal magnetic field is the lower ferromagnetic layer 11, and the upper ferromagnetic layers 13 and 13a are antiferromagnetically coupled to each other. This antiferromagnetic coupling is found in the artificial lattice shown in the prior art, and therefore depends on the layer thickness of the intermediate layer (Cu) 12b.

FeMn / Co was used as the spin valve film.
Although an example of Fe / Cu / CoFe is shown, when no antiferromagnetic layer is used, for example, Co / Cu / NiFe
The structure of the present invention can also be applied to a giant magnetoresistive layer including two or more ferromagnetic layers having different coercive forces. Further, when using an antiferromagnetic layer, FeM
FeMn / Ni other than n / CoFe / Cu / CoFe
As long as it has a structure of antiferromagnetic layer / ferromagnetic layer / nonmagnetic conductive layer / ferromagnetic layer such as Fe / Cu / NiFe, the structure of the present invention can be used regardless of the material. Further, even when the antiferromagnetic layer is not used and the Co / Cu / NiFe giant magnetoresistive layer is different from the material shown in this embodiment, the high coercive force layer / nonmagnetic conductive layer / soft magnetic layer is obtained. As long as it has a layer structure, the structure of the present invention can be used regardless of the material.

Example 16 A magnetic head having the same structure as in Example 7 except that the magnetization direction of the antiferromagnetic layer (FeMn) 14 is inclined 20 degrees toward the magnetization direction of the lower ferromagnetic layer (CoFe) 11 Obtained.

The RH curve of the obtained magnetic head is almost the same as that of FIG. 15, the shift is remarkably relaxed, and a sufficient resistance change can be obtained even when a positive signal magnetic field is applied. it can.

Example 17 As shown in FIG. 27, a CoPt high coercive force film 2 (20 nm thick) for longitudinal bias was sputter-deposited on a plastic substrate 4 to form a pair of patterns by ion milling (the interval was 3 μm, 3 μm × 40 μm shape that is long in the track width direction).

Next, the first magnetic underlayer film 16-1 (4 nm thick C
oZrNb amorphous film), second magnetic underlayer film 16-
2 (Ni ₈₀ Fe ₂₀ film added with 5 at% of Cr, 4 nm
Thickness), magnetic rotation film 11 (Co ₉₀ Fe ₁₀ film, 3 nm
Thickness), non-magnetic film 5 (Cu film, 3 nm thickness), magnetization pinned film 13
(Co ₉₀ Fe ₁₀ film, 2.5 nm thickness), antiferromagnetic bias film 14 for fixing magnetization (Ir ₂₅ Mn ₇₅ film, 10 nm thickness),
A protective film 15 (TiN film, 20 nm thick) was sequentially formed by sputtering, and finely processed by ion milling into a striped shape long in the track width direction (2 μm × 80 μm).

Further, Ta (10 nm thickness) / Cu (100 nm thickness)
/ Ta (10 nm thick) laminated electrode 3 is formed by sputtering, and the interval (corresponding to the reproduction track width) is 1 μ by ion milling.
Finely processed to m.

After that, after heat treatment in a rotating magnetic field of 250 ° C. × 1 hour, heat treatment in a static magnetic field in the longitudinal direction of the spin valve film stripe is performed at 250 ° C. × 5 minutes, and 220 ° C. during cooling.
Heat treatment that rotates the static magnetic field direction by 90 ° (corresponding to the blocking temperature of the IrMn film) is performed, and after cooling to room temperature, the hard film is magnetized in the longitudinal direction of the MR stripe (the static magnetic field direction during annealing at 250 ° C x 5 minutes). ) Was done.

As a result, the magnetization of the pinned film is pinned approximately in the width direction of the spin valve film stripe (head depth direction) into which the signal magnetic field flows, and the magnetization of the magnetization rotation layer exists along the length of the spin valve film stripe. FIG. 28 shows the resistance-magnetic field characteristics of this spin valve element measured in the plus-minus 200 Oe magnetic field range. A sense current of 10 mA was passed from left to right in FIG. ΔR / R (definition: (maximum resistance-minimum resistance) / minimum resistance) was 6%, which showed a good linear resistance-magnetic field characteristic with no hysteresis and almost no operating point shift.

Therefore, a shield type magnetic head using this spin valve element was manufactured. An amorphous CoZrNb film formed by sputtering was used for the upper and lower shield films, and a laminated film of Si (10 nm) / SiO _x (10 nm) / alumina (50 nm) was used for the upper and lower gap films. Machined to 50% slider shape (spin valve film width: 2 μm), Hc = 25
The recording / reproducing characteristics were measured at a flying bite of 40 nm using a CoPt medium with Mr δ (Mr: residual magnetic field, δ: medium recording layer thickness) = 1 menu / cm ² at 00 Oe. The recording is MIG using a FeTaN film with a saturation magnetic flux density of 1.6 T.
It was performed by the head.

As a result, a Barkhausen noise-free reproduced waveform with little waveform asymmetry due to a good linear response as shown in FIG. 29 was obtained (sense current: 10 mA).
Also, a standardized reproduction output of 0.8 mVpp / μm was obtained. Also, a good linear recording density of D ₅₀ = 150 KFCl was obtained.
Further, when a 0.5 μm micro track was recorded on the medium and the off-track characteristic of the reproduction output was examined, the results shown in FIG. 30 were obtained. It can be seen that the effective playback track width at which the output is halved (6 dB down) is achieved with a narrow track width playback corresponding to approximately 1 μm of the electrode interval.

From the above results, the value of the film thickness of the magnetization rotation layer and the magnetic underlayer × the saturation magnetic field can be calculated by multiplying the film thickness of the magnetization fixed film × the saturation magnetic field by 3
By setting the value more than twice, the reproducing head with good linear response without operating point shift is provided with the hard film wider than the electrode interval exchange-coupled with the magnetic underlayer only on the edge part deviated from the magnetic sensitive part. This shows that a spill valve GMR head with a narrow gap of 0.1 μm or less and a narrow track of 1 μm without crosstalk can be realized with high sensitivity.

Embodiment 18 FIG. 31 shows an embodiment of the present invention in which the spin valve element is retracted from the medium facing surface. After forming a shield and a gap film (not shown) on the substrate 4 as required, a pair of hard bias films 2 and a magnetic underlayer film 1 as shown in Example 17 are formed.
6, spin valve element receding from the medium facing surface (magnetization rotation layer 11, nonmagnetic layer 5, magnetization pinned layer 13, bias film 1
4 are sequentially laminated), and a pair of electrodes 3 is formed. In order to retract the spin valve element from the medium facing surface, the base film 16
Then, after spin-valve elements are continuously formed, only the spin-valve elements are selectively removed by chemical etching or the magnetic underlayer film 16 is left alone for milling.

Cu used for the non-magnetic layer in the spin valve element
The FeMn film and the like used for the bias film 14 and the like have a problem in corrosion resistance, and if exposed to the medium facing surface, a problem occurs in reliability. However, according to this embodiment, by retracting the spin valve element from the medium facing surface, the spin valve element can be protected by the gap film on alumina, the reliability of the spin valve element can be ensured, and the magnetic underlayer film can be secured. Since the magnetization rotation layer is formed by exchange coupling with 16, the signal magnetic field can be effectively drawn into the magnetic field of the spin valve element even if it recedes from the medium facing surface, so that highly sensitive reproduction can be maintained.

In order to maintain high-sensitivity reproduction, it is desirable that the amount of receding of the spin valve element is smaller than the characteristic length λ expressed by the following equation in which the signal magnetic field is attenuated.

Λ = (g μt / 2) ^0.5 μ: Permeability of the magnetic underlayer, g: Interval between shield and MR,
t: Thickness of magnetic underlayer For example, when g = 0.1 μm, μ = 1000, and t = 10 nm, λ is about 0.7 μm, and a recession amount less than this is desirable. This amount of retreat is a value that can be achieved by high precision polishing in slider processing.

[0089]

As described in detail above, in the magnetic head of the present invention, the magnetization direction of the magnetization pinned layer and the magnetization direction of the easy axis of magnetization in the magnetization rotation layer can be made substantially orthogonal to each other, so that the operating point Can be shifted. As a result, it is possible to effectively use the high resistance change rate,
Since good linearity can be obtained with respect to the signal magnetic field, a magnetic head having high sensitivity and high frequency can be obtained.

The operating point can be shifted by setting V ₂ / V ₁ ≧ 3 defined above.

Further, the operating point can be shifted also by stacking a magnetic layer on the magnetization fixed layer or the magnetization rotation layer with a nonmagnetic layer interposed therebetween.

As a result, a high resistance change rate can be effectively used and good linearity can be obtained with respect to the signal magnetic field, so that a magnetic head with high sensitivity and high frequency can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram for explaining a phenomenon in which an operating point shifts in a magnetoresistive film having a rectangular pattern.

FIG. 2 is a diagram showing the dependency of the resistance value R of the giant magnetoresistive effect on the applied magnetic field H _ex .

FIG. 3 shows a change ρ in specific resistance depending on the inclination of the magnetization pinned layer.
It is a figure which shows the change by the magnetic field H of '.

4A and 4B are views showing the configuration of a magnetic head of Example 1, where A is a plan view and B is a sectional view.

FIG. 5 is a diagram showing a magnetization direction of Example 1.

FIG. 6 is a diagram showing the relationship between the applied magnetic field and the resistance (hereinafter referred to as the RH curve) of the magnetic head obtained in Example 1.

FIG. 7 is a diagram showing a magnetization direction of Example 2.

FIG. 8 is a diagram showing an RH curve of the magnetic head obtained in Example 2;

9 is a diagram showing an RH curve of the magnetic head obtained in Comparative Example 1. FIG.

FIG. 10 is a diagram showing a magnetization direction of Comparative Example 2.

11 is a diagram showing an RH curve of the magnetic head obtained in Comparative Example 2. FIG.

FIG. 12 is a diagram showing an RH curve of the magnetic head obtained in Example 4;

FIG. 13 is a diagram showing a magnetization direction of Example 5;

14A and 14B are views showing the configuration of a magnetic head of Example 7, where A is a plan view and B is a sectional view.

15 is a diagram showing an RH curve of the magnetic head obtained in Example 7. FIG.

16 is a sectional view of a magnetic head of Comparative Example 3. FIG.

17 is a diagram showing an RH curve of the magnetic head obtained in Comparative Example 3. FIG.

FIG. 18 is a diagram showing an RH curve of the magnetic head obtained in Example 8;

19 is a diagram showing an RH curve of the magnetic head obtained in Example 9. FIG.

FIG. 20 is a cross-sectional view of the magnetic head of Example 10.

FIG. 21 is a cross-sectional view of a magnetic head of Example 11.

22 is a sectional view of a magnetic head of Example 12. FIG.

23 is a diagram showing an RH curve of the magnetic head obtained in Example 12. FIG.

FIG. 24 is a cross-sectional view of a magnetic head of Example 13.

FIG. 25 is a cross-sectional view of a magnetic head of Example 14.

FIG. 26 is a sectional view of a magnetic head of Example 15.

FIG. 27 is a perspective view showing a schematic configuration of a magnetic head including a spin valve element of Example 17.

28 is a diagram showing resistance-magnetic field characteristics of the spin valve element of Example 17. FIG.

FIG. 29 is a reproduction waveform of the magnetic head of Example 17.

FIG. 30 shows off-track characteristics of reproduction output of the magnetic head of the seventeenth embodiment.

31 is a perspective view showing the arrangement of spin valve elements in the magnetic head of Example 18. FIG.

[Explanation of symbols]

1 ………… Spin valve laminated film, 2 ………… High coercive force film, 3
… Lead, 4 ………… Support substrate, 5 ………… Non-magnetic layer,
11 ... Lower ferromagnetic layer, 12 ... Intermediate layer, 13 ...
Upper ferromagnetic layer, 14 ... antiferromagnetic layer, 15 ... protective layer, 16 ... ferromagnetic layer, 17 ... CoZrNb layer,
18 ... An oxide layer of CoZrNb.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hitoshi Iwasaki 1 Komukai Toshiba-cho, Saiwai-ku, Kawasaki-shi, Kanagawa Toshiba Research & Development Center, Ltd. (72) Inventor Yuzo Ueguchi Komukai, Kouki-ku, Kawasaki-shi, Kanagawa TOSHIBA-Cho No. 1 in stock company Toshiba Research and Development Center (72) Inventor Susumu Hashimoto Komukai, Kozaki-ku, Kanagawa Koumu TOSHIBA-Cho 1 company in stock company Toshiba Research and Development Center (72) Inventor Masaji Sahashi Kawasaki City, Kanagawa Prefecture Komukai Toshiba-cho, Saiwai-ku, Toshiba Research & Development Center

Claims (11)

[Claims] 1. A magnetic head comprising a magnetic pinned layer, a magnetization rotating layer having an easy axis of magnetization in the head track width direction, and a magnetic laminate including a nonmagnetic layer interposed between the magnetization fixed layer and the magnetization rotating layer. The magnetization direction of the magnetization pinned layer is changed from the head depth direction to the magnetization direction of the magnetization rotation layer so that the magnetization of the magnetization pinned layer and the magnetization of the magnetization rotation layer are orthogonal to each other when the signal magnetic field is 0. A magnetic head characterized by an inclination of less than 30 degrees. 2. The product of the saturation magnetization and the volume of the magnetization pinned layer or the ferromagnetic layer pinned by the magnetization pinned layer is V
_1. The magnetic head according to claim ₁ , wherein V ₂ / V ₁ ≧ 3, where V ₂ is the product of the saturation magnetization and the volume of the magnetization rotation layer. 3. The magnetization direction of the magnetization pinned film is inclined in the range of 1 to 25 degrees from the head depth direction to the magnetization direction of the magnetization rotation layer. Magnetic head. 4. A magnetic head including a magnetic pinned layer having a magnetization direction in the head depth direction, a magnetic rotation layer, and a magnetic laminated body including a non-magnetic layer interposed between the magnetization fixed layer and the magnetic rotation layer. Then, when the signal magnetic field is 0, the magnetization easy axis of the magnetization fixed layer is perpendicular to the magnetization direction of the magnetization fixed layer so that the magnetization of the magnetization fixed layer is orthogonal to the magnetization of the magnetization fixed layer. Towards 30
A magnetic head characterized by being inclined to less than a degree. 5. The product of the saturation magnetization and the volume of the magnetization pinned layer is V ₁ , and the product of the saturation magnetization and the volume of the magnetization rotation layer is V ₂
The magnetic head according to claim 4, wherein V ₂ / V ₁ ≧ 3. 6. The magnetization direction of the magnetization pinned film is inclined in the range of 1 degree to 25 degrees from the head depth direction toward the magnetization direction of the magnetization rotation layer. Magnetic head. 7. A magnetization fixed layer having a magnetization direction in the head depth direction, a magnetization rotation layer having an easy axis of magnetization in the head track width direction, and a nonmagnetic layer interposed between the magnetization fixed layer and the magnetization rotation layer. A magnetic head comprising a magnetic layered body including V, where V ₁ is the product of the saturation magnetization of the magnetization pinned layer and the volume, and V ₂ is the product of the saturation magnetization of the magnetization rotation layer and the volume.
A magnetic head characterized in that ₂ / V ₁ ≧ 3. 8. A magnetization pinned layer having a magnetization direction in the head depth direction, a magnetization rotation layer having an easy axis of magnetization in the head track width direction, and a nonmagnetic layer interposed between the magnetization rotation layer and the magnetization rotation layer. A magnetic head comprising a magnetic layered body including a magnetic layer, wherein a magnetic layer is laminated on the magnetic layered body, and the magnetization direction of the magnetic layer is substantially antiparallel to the magnetization direction of the magnetization pinned layer. A magnetic head, wherein the magnetization of the magnetization pinned layer and the magnetization of the magnetization rotation layer are substantially orthogonal to each other by being magnetostatically coupled to the film. 9. A magnetization rotating film whose magnetization is rotated by a signal magnetic field formed on a ferromagnetic underlayer, wherein the signal magnetic field is substantially 0 and the magnetization is oriented in the track width longitudinal direction. Magnetization pinned film whose magnetization does not move substantially,
Here, the magnetization in the magnetization pinned film is pinned substantially in the signal magnetic field inflow direction, and a magnetoresistive effect utilizing spin-dependent scattering formed of a non-magnetic film interposed between the magnetization rotation film and the magnetization pinned film. An element, a pair of bias films formed immediately below the surface of the ferromagnetic underlayer on both sides of the magnetization rotation film, which are separated from the portion of the magnetization rotation film that rotates in response to a signal magnetic field from a recording track, and the magnetoresistive film. A magnetoresistive head comprising an electrode for supplying a sense current to the head. 10. The magnetoresistive film according to claim 12, wherein the ferromagnetic underlayer film is formed by laminating a Co-based amorphous alloy film and an alloy film made of at least one selected from NiFe and NiFeX. Effect type head, where X is Ta, Zr, Nb, Hf, Cr, Rh, Ir, R
The magnetic head according to claim 9, wherein the magnetic head is at least one selected from the group consisting of e, Ru, Pd, Pt, Cu, Au, and Ag. . 11. A part or all of the magnetic field detection film, the non-magnetic film and the magnetization fixed film are recessed rearward from the medium facing surface of the head as compared with the ferromagnetic underlayer film and the bias film. The magnetoresistive head according to claim 9, wherein the head is a magnetoresistive head.