JPH08167122A - Single magnetic pole head for perpendicular magnetic recording - Google Patents

Abstract

PURPOSE: To stably control the magnetic domain structure of a main magnetic pole and to provide a single magnetic pole head allowing a two-layered medium to satisfactorily exhibit ability peculiar to the medium and capable of eliminating the effect of small track width. CONSTITUTION: At least a main magnetic pole 2 receiving a signal magnetic field from a recording medium is formed on a nonmagnetic substrate 1. At least part of the magnetic pole 2 has a three-layered structure formed by interposing a middle layer 2c of a nonmagnetic material between a pair of magnetic substance layers 2a, 2b. Electric current is supplied in the signal magnetic flux transmission direction of the magnetic pole 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single magnetic pole head for perpendicular magnetic recording used in a perpendicular magnetic recording system suitable for increasing the recording density of magnetic disk devices, magnetic tape devices and the like.

[0002]

2. Description of the Related Art At present, a perpendicular magnetic recording method has been proposed as a magnetic recording method capable of greatly improving the recording density.

Further, as a magnetic head based on the perpendicular magnetic recording method, a magnetic head to which an MR element utilizing a magnetoresistive effect is applied so that a reproduction output can be obtained regardless of the relative speed of the magnetic head and the medium is used as a reproduction head. It has been put to practical use.

[0004]

In the magnetic head using the perpendicular magnetic recording method, demagnetization of the magnetic recording medium does not easily occur even at a high linear recording density, but the spacing between the magnetic head and the recording medium and the magnetic head. The effect of the efficiency of will be significant. In order to increase the efficiency of the magnetic head, it is necessary to improve the effective magnetic permeability of the return path by forming the main magnetic pole and the return magnetic path, and to shorten the magnetic path length.

In order to increase the density of magnetic recording, it is necessary to reduce the track width of the recording medium. In response to this request, the magnetic head, for example, FIG.
As shown in (a) to (c), the track width becomes narrow.
The magnetic heads of FIGS. 27A and 27B have a wide track width and a relatively wide track width, respectively, so that the demagnetizing field does not affect the easy axis in the track width direction.

However, when the track width becomes narrow in the magnetic head as shown in FIG. 27C, the magnetic head is
Since the demagnetizing field affects the easy axis, it becomes difficult to control the magnetic domain of the main magnetic pole, and the effective magnetic permeability decreases. Due to such a cause, as a specific phenomenon, a problem occurs such that noise accompanying movement of the domain wall, magnetization operation in the easy axis direction, and waveform distortion are likely to occur in the magnetic head.

Also, regarding the magnetic path length, when recording and reproducing are performed with the same magnetic pole, considering that a recording coil is formed in the magnetic head, a limit is reached even in shortening the magnetic path length of the magnetic head. I will end up. That is, this means that the magnetic path length of the magnetic head is limited.

Therefore, the present invention has been made in view of the above-mentioned circumstances, and stably controls the magnetic domain structure of the main magnetic pole to sufficiently bring out the original capability of the two-layered medium to reduce the influence of the narrow track width. An object is to provide a single magnetic pole head for perpendicular magnetic recording which can be prevented.

[0009]

In order to solve the above-mentioned problems, a single magnetic pole head for perpendicular magnetic recording according to the present invention comprises:
A main magnetic pole that receives at least a signal magnetic field from a recording medium is formed on a non-magnetic substrate, and at least part of the main magnetic pole has a pair of magnetic layers with a three-layer structure with an intermediate layer made of a non-magnetic material interposed therebetween. At the same time, the current is supplied in the signal magnetic flux transmission direction of the main magnetic pole.

Here, the single magnetic pole head for perpendicular magnetic recording may be provided with an auxiliary magnetic pole forming a return magnetic path magnetically coupled to the rear end side of the main magnetic pole.

In the single magnetic pole head for perpendicular magnetic recording, at least a part of the magnetic material layer constituting the main magnetic pole is made of a magnetic material having a magnetoresistive effect, and the magnetic material is recorded on the recording medium by the magnetoresistive effect. It is also possible to configure a reproducing head from which the signal is reproduced.

On the main magnetic pole, it is preferable that the electrode on the sliding surface side for passing a current through the magnetic body of the main magnetic pole is grounded.

Further, in the single magnetic pole head for perpendicular magnetic recording,
The signal recorded is reproduced by forming a reproducing magnetic path for circulating the magnetic field from the recording medium by short-circuiting the recording magnetic path formed in the direction opposite to the sliding surface side of the recording medium of the MR element. I have to.

Further, the single magnetic pole head for perpendicular magnetic recording is
A configuration may be used in which a return magnetic path that causes a bias magnetic field applied to the MR element to return from the magnetic path that guides the MR element to the tip side is provided on the tip side of the main pole.

[0015]

In the single magnetic pole head for perpendicular magnetic recording according to the present invention, at least a part of the main magnetic pole has a three-layer structure with a pair of magnetic layers with an intermediate layer made of a nonmagnetic material interposed therebetween.
By supplying the current in the signal magnetic flux transmission direction of the main pole, the domain wall disappears even when the track width of the recording medium is narrow when controlling the magnetic domain structure, and the triangular domain in the main pole magnetic body is eliminated to eliminate the main domain. Waveform distortion is prevented by increasing the effective permeability of the magnetic poles.

By providing the auxiliary magnetic pole as a return magnetic path magnetically coupled to the rear end side of the main magnetic pole, a phenomenon appearing due to a narrow track width can be avoided and an efficient signal without waveform distortion can be obtained.

At least a part of the magnetic material layer forming the main pole is composed of a magnetic material having a magnetoresistive effect, and the magnetoresistive effect of the magnetic material reproduces the signal recorded on the recording medium to obtain The reproduced signal to be reproduced has a higher output so that the reproduced signal can be obtained regardless of the relative speed between the magnetic head and the recording medium.

By forming an electrode on the main magnetic pole on the sliding surface side through which a current flows through the magnetic material of the main magnetic pole, electrostatic breakdown due to static electricity due to sliding of the magnetic head and the recording medium is prevented and , The noise due to dive electricity is suppressed.

In this single magnetic pole head for perpendicular magnetic recording, M
The recorded signal is reproduced by forming a reproduction magnetic path that short-circuits the recording magnetic path formed in the direction opposite to the sliding surface side of the recording medium of the R element to circulate the magnetic field from the recording medium. As a result, a sufficient magnetic field can be applied by saturating the magnetic material short-circuited during recording, and a reproducing magnetic path can be constructed through the magnetic material short-circuited during reproduction to obtain an efficient and high output.

In the single magnetic pole head for perpendicular magnetic recording, the bias magnetic field applied to the MR element is provided on the tip side of the main pole from the tip magnetic path to the return magnetic path, so that the bias magnetic field required for the MR element is provided. Are circulated through the return magnetic path to reduce the magnetic field applied to the recording medium from the tip of the single magnetic pole. Therefore, the demagnetization of the recording medium due to the bias magnetic field is less likely to occur.

[0021]

EXAMPLES Examples of a single magnetic pole head for perpendicular magnetic recording according to the present invention will be described below with reference to the drawings.

In this embodiment, an example will be given as an example in which the present invention is applied to, for example, a single magnetic pole head (hereinafter referred to as a magnetic head) used for perpendicular magnetic recording.

In the first embodiment, as shown in FIGS. 1 and 2, for example, the magnetic head has a main magnetic pole that receives at least a signal magnetic field from a recording medium on a substrate 1 via a nonmagnetic insulating layer 1a. 2 is formed, and at least a part of the main magnetic pole 2 has a three-layer structure by adding a pair of magnetic layers 2a and 2b to an intermediate layer 2c made of a non-magnetic material.
A current is made to flow in the signal magnetic flux transmission direction of the main magnetic pole 2.

An insulating film 1a made of Al ₂ O ₃ or the like is formed on a member made of a nonmagnetic material such as Al ₂ O ₃ —TiC as the substrate 1.

As the main magnetic pole magnetic body constituting the main magnetic pole 2, a Co alloy type amorphous material or a FeN type microcrystalline material having a high saturation magnetic flux density can be used in addition to the Ni-Fe alloy. The main pole 2 is formed by giving magnetic anisotropy in the track width direction.

As the non-magnetic intermediate layer of the main pole 2,
Non-magnetic metals such as Cr, Ag, Mo, Ti, W and Ta and non-magnetic materials such as Al ₂ O ₃ and SiO ₂ can be used.

By thus forming a pair of main magnetic pole magnetic layers with the intermediate layer interposed therebetween to form a three-layer structure, the magnetization directions of the upper and lower two main magnetic pole magnetic layers are antiparallel to each other. This reduces the demagnetizing field when the easy axis of magnetization is taken in the track width direction of the recording medium. In addition to this effect, by passing a current through the main magnetic pole 2 having a three-layer structure, the magnetic head can stably control the direction of magnetization by the magnetic field generated by the current. As a result, the current applied to this magnetic head is made to flow in the signal magnetic flux transmission direction so as to control the magnetic domain structure.

However, it is known that in a laminated film having such a non-magnetic intermediate layer, the effective magnetic permeability is lowered by passing a current. This phenomenon causes a magnetic field to be applied in the track width direction by the current when a current is applied in the signal magnetic field direction, hindering the magnetization rotation in the signal magnetic field direction, and lowering the effective magnetic permeability. Therefore, the current at the position where the magnetic permeability peaks in FIG. 3 is the optimum current.

In the case of a small signal magnetic field, the pair of magnetic layers 2
a three-layer structure main pole 2 having an intermediate layer 2c between a and 2b
Of the effective magnetic permeability μ _eff is the saturation magnetic flux density B _S , the anisotropic magnetic field of the material is H _k , and the magnetic field due to the magnetic domain stabilizing current is H _x.
Then, μ _eff = B _S / (H _k + H _x ) ... (1)

By setting the current value of the current magnetic field to an appropriate value in accordance with the track width and the thickness of the main magnetic pole using the relationship shown in the equation (1), the effective magnetic permeability in the signal magnetic field transmission direction can be obtained. It is possible to provide a single magnetic pole head capable of increasing perpendicular magnetic recording with high efficiency and high output.

A magnetic path for guiding a magnetic field to the tip of this magnetic head, that is, the tip magnetic path 3 facing the sliding surface of the recording medium, as shown in FIG. 2, has a pair of magnetic layers through an intermediate layer 2c. The main magnetic pole 2 having a three-layer structure in which 2a and 2b are formed may be extended and formed. Alternatively, a soft magnetic material having a high magnetic permeability and a high saturation magnetic flux density, such as a Co alloy-based amorphous material or a FeN-based microcrystalline material, may be formed with a film thickness of 0.1 μm to 0.5 μm.

Electrodes 4a and 4b are formed on the main magnetic pole 2. The electrodes 4a and 4b are provided for passing a current that controls the magnetic domain structure of the magnetic body of the main magnetic pole 2.
Here, the electrode 4b may be provided at any position within a range in which the main magnetic pole can be energized without causing any problem. Here, the electrode 4a
Potential at the earth and the earth potential and the electrode 4b
The electric current may flow through the main magnetic pole 2 due to the potential difference from the electric potential. In the magnetic head, the electrode 4a on the sliding surface side is set to the ground potential to prevent electrostatic breakdown due to static electricity due to sliding of the magnetic head and the recording medium, and to escape the jumping electric charge through the electrode and eliminate noise. it can.

The thickened portion formed on the main magnetic pole 2 is referred to as a main magnetic pole thickened film 5.

The main magnetic pole thickening film 5 is provided to reduce the magnetic resistance of the entire closed magnetic circuit because the main magnetic pole 2 is thin and the magnetic resistance becomes large. The main magnetic pole thickening film 5 has a lower magnetic flux density as compared with the main magnetic pole 2 as the thickness is increased. Therefore, in addition to the Co-based amorphous film, permalloy may be used as another material. This portion is deposited by sputtering, vapor deposition, electroplating, or the like.

An insulating layer 6a is formed on the main pole thickening film 5 to electrically insulate it from a coil 7 which will be described later. The insulating layer 6a is formed, for example, by forming an insulating film such as Al ₂ O ₃ or SiO ₂ by sputtering or by thermosetting a photosensitive organic material.

The coil 7 is made of a conductor. The coil 7 is made of a material having a low electric resistivity, such as gold or copper.

In this magnetic head, the insulating layer 6b serves to electrically insulate the coil 7 and the return magnetic path 8 which will be described later from the coil 7 and the main magnetic pole thickening film 5 and the coil 7 so as to electrically insulate each other. It is formed between the magnetic paths 8.

The return magnetic path 8 is a magnetic path for efficiently returning the magnetic flux drawn by the main magnetic pole 2 to the double-layered medium backing layer, and is formed by, for example, Ni-Fe alloy plating or the like.

With this structure, the nonmagnetic material transmits the signal magnetic flux to the main magnetic pole 2 having the three-layer structure in which the intermediate layer is arranged between the main magnetic pole magnetic bodies to control the magnetic domain structure. By flowing in the direction, the domain wall is eliminated even in a narrow track width, and the triangular magnetic domain of the magnetic body is eliminated in the main magnetic pole 2, so that the effective magnetic permeability in the main magnetic pole 2 can be increased and the noise accompanying the domain wall movement can be increased. It also makes it difficult for waveform distortion to occur. Therefore, it is possible to provide a magnetic head for perpendicular magnetic recording that is efficient, has high output, and has no waveform distortion.

Even if the auxiliary magnetic pole is provided as a return magnetic path magnetically coupled to the rear end side of the main magnetic pole 2, the phenomenon caused by the narrow track can be avoided.

A second embodiment of the single magnetic pole head for perpendicular magnetic recording of the present invention will be described with reference to FIGS. 4 and 5. Here, common parts are given the same reference numerals, and description thereof is omitted.

On the substrate 1, for example, as shown in FIG.
Insulating layer 1a made of Al ₂ O ₃ on a non-magnetic substrate such as ₂ O ₃ -TiC
Are formed. Further, a step is formed on the insulating layer 1a by the step surface 1b. This step is formed by a physical treatment such as ion milling or a chemical treatment such as reactive ion etching using a resist formed in the photolithography process as a mask. At this time, the side surface 1b is processed so as to have a taper.

A return magnetic path 8a is formed on the insulating layer 1a having this step. This return magnetic path 8a is
For example, Ni-Fe is formed by a method such as plating. The return magnetic path 8a is a return magnetic path for efficiently returning the magnetic flux drawn by the main magnetic pole 2 described later to the two-layer film medium backing layer.

After each layer is formed in this way, the step surface 1b on the return magnetic path 8a is filled with a non-magnetic material to flatten the surface. Examples of this non-magnetic material include materials such as Al ₂ O ₃ . This embedding process is performed so that the film thickness is at least the step 1b of the return magnetic path 8a or more. After that, the surface of the return magnetic path 8a, which is the buried return path, is flattened by a method such as polishing until it is exposed. Since the main magnetic pole 2 made of a thin film having a magnetoresistive effect is formed on the flattened surface 8A, it is desirable to have sufficient smoothness.

By such processing, it is possible to eliminate the step when the main magnetic pole 2 formed later by the magnetoresistive thin film is formed.

On this flattened surface 8A, a layer using a short-circuit magnetic material is formed as a reproducing magnetic path 9. The reproducing magnetic path 9 is saturated during recording and has a role of promptly guiding the magnetic flux passing through the MR element to the return magnetic path 8a during reproduction. Therefore, it is necessary to set the film thickness so that the short-circuit magnetic material of the reproducing magnetic path 9 is not saturated during reproduction, but is saturated during recording. As a method of setting the film thickness, for example, the main magnetic pole film may be extended and used.

The main magnetic pole 2 is provided on the flattened surface 8A on the sliding surface side of the magnetic head, that is, on the tip side of the magnetic head.
At least a part of the main magnetic pole 2 is a pair of magnetic layers 2a, 2
b has a three-layer structure with an intermediate layer 2c made of a non-magnetic material, and a structure in which a current is supplied in the signal magnetic flux transmission direction of the main magnetic pole 2. A current flows in the main magnetic pole 2 in the signal magnetic flux transmission direction in order to control the magnetic domain structure (see FIG. 5).

The main magnetic pole 2 may be made of a magnetic material having a magnetoresistive effect. As the magnetic substance having such a magnetoresistive effect, for example, a Ni—Fe—Co alloy having a high resistivity can be used in addition to the Ni—Fe alloy.
As a result, the recording medium is formed by imparting magnetic anisotropy in the track width direction.

Further, as the intermediate layer 2c, Cr, Ag, Mo,
A non-magnetic metal such as Ti, W, Ta or a non-magnetic material such as Al ₂ O ₃ or SiO ₂ is used.

As described above, the pair of magnetic layers in the main magnetic pole 2 are made of thin films having a magnetoresistive effect.
The single magnetic pole head for perpendicular magnetic recording of the present invention can be reproduced by the vertical two-layer MR element, and a higher output can be obtained regardless of the relative speed of the magnetic head and the recording medium, and the magnetic field having a large S / N ratio. It can be provided as a recording / reproducing head.

Tip magnetic path 3 as a magnetic path for guiding a magnetic field to the tip of this magnetic head facing the sliding surface of the recording medium.
May be formed, for example, by extending a thin film having a magnetoresistive effect which constitutes a vertical two-layered MR element, and may be formed from a soft magnetic material having a high magnetic permeability and a high saturation magnetic flux density such as another Co-based amorphous alloy.
You may form with a film thickness of 0.1 micrometer-0.5 micrometer.

As described above, the pair of magnetic layers 2a, 2
Electrodes 4a and 4b made of conductors are formed to pass a current for controlling the magnetic domain structure of the main magnetic pole 2 having a magnetic two-layer structure by b.

A part or all of the main pole 2 is a vertical two-layer MR.
In the case of being composed of an element, this current flowing between the electrodes 4a and 4b becomes a sense current for detecting a change in magnetoresistance due to a signal magnetic flux. If the potential of the electrode 4a is set to the ground potential and a current is passed through the main magnetic pole 2 by the potential difference between the potential of the electrode 4b and the ground potential, electrostatic breakdown due to static electricity due to sliding of the magnetic head and the recording medium is prevented. At the same time, it is possible to prevent the generation of noise by letting the jumping charges escape through the electrodes. The electrode 4b does not pose any problem even if it is provided at any position within a range where the main magnetic pole 2 can be energized.

Bias conductor 10 arranged on main pole 2
Is provided in order to improve the linearity of the MR element by supplying a bias current to the bias conductor 10 and generating a magnetic field that returns from the MR element of the main pole 2 to the bias return magnetic body.

The bias return magnetic path 11 formed so as to cover the bias conductor 10 from the electrode 4a is formed of a magnetic material for bias return. Bias return magnetic path 1
1 has a role of circulating a bias magnetic field from the sliding surface side of the MR element to the rear portion of the MR element. By providing the bias return magnetic path 11, the efficiency of the bias magnetic field generated by the bias current to the MR element can be increased.

Further, by setting the film thickness and the saturation magnetic flux density so that the magnetic substance of the bias return magnetic path 11 is saturated in the state where an appropriate bias magnetic field is applied to the MR element,
The bias current dependence of the bias magnetic field can be moderated at the bias optimum point.

Further, by providing the bias return magnetic path 11, the magnetic field applied to the recording medium when the MR element is biased can be reduced and demagnetization of the recording medium can be prevented.

By the way, at least one side of the bias return magnetic path 11 must be electrically separated from the path of the sense current so that the bias return magnetic path 11 does not bypass the sense current flowing in the MR element (see FIG. 3). reference).

The coil 7 made of a conductor is made of a material having a low electric resistivity, such as gold or copper, and is formed with a sufficient number of turns for recording information on a recording medium.

A recording magnetic path 8b for transmitting a magnetic flux when a recording current is applied to the coil 7 is formed so as to cover the coil 7. The recording magnetic path 8b is formed by, for example, plating a Ni—Fe alloy by a method such as plating.

An insulating layer 12 is provided to electrically insulate the coil 7 from the reproducing magnetic path 8a and the recording magnetic path 8b.
a and 12b are provided. Insulating layers 12a, 12b
Is formed by, for example, forming an insulating film of Al ₂ O ₃ , SiO _2, or the like by sputtering, or by thermosetting a photosensitive organic material.

By providing the bias return magnetic body for circulating the bias magnetic field from the sliding surface side of the MR element to the rear portion of the MR element, the efficiency of the bias magnetic field generated by the bias current to the MR element can be increased. At the same time, by providing a bias return magnetic path, M
The magnetic field applied to the recording medium when a bias is applied to the R element can be reduced to prevent demagnetization of the recording medium.

Further, the bias current dependence of the bias magnetic field is biased by setting the film thickness and the saturation magnetic flux density so that the magnetic substance of the bias return magnetic path is saturated in the state where an appropriate bias magnetic field is applied to the MR element. It can be loosened at the optimum point. Therefore, it is possible to provide a perpendicular magnetic recording single magnetic pole head which saves power and has little variation.

Next, a method of manufacturing the magnetic head of the first embodiment will be described with reference to the sectional views of the essential parts shown in FIGS.

A procedure of a method for manufacturing a single magnetic pole head for perpendicular magnetic recording in which at least a main magnetic pole for applying a signal magnetic field to a recording medium is formed on a non-magnetic substrate will be briefly described. Here, common portions are given the same reference numerals, and description thereof is omitted.

First, the insulating layer 1a is formed on the substrate 1. On this insulating layer 1a, as shown in FIG. 6, a main pole 2 having a three-layer structure is formed.

Next, a tip magnetic path 3 made of a conductor is formed at the end of the main pole 2 on the sliding surface side when it is used as a magnetic head (see FIG. 7).

Next, a thin film of the electrode 4a is formed on the tip magnetic path 3, as shown in FIG. This electrode 4a
On the surface of the main magnetic pole 2 which does not overlap with the main magnetic pole 2 as shown in FIG. Since the magnetic flux density of the main magnetic pole thickening film 5 is lower than that of the main magnetic pole 2, permalloy may be used instead of the Co-based amorphous film, and the main magnetic pole thickening film 5 is deposited by sputtering, vapor deposition, electroplating or the like.

After the main magnetic pole thickening film 5 is formed, an insulating layer 6a is formed so as to cover the main magnetic pole thickening film 5, as shown in FIG. On the insulating layer 6a, as shown in FIG. 11, the coil 7 is formed with a sufficient number of turns for recording information on the recording medium. By forming the insulating layer 6a in advance, the coil 7 and the main pole thickening film 5 are electrically insulated.

In the next step, an insulating layer 6b made of the same material as the insulating layer 6a is formed so as to cover the coil 7 (see FIG. 12).

In order to connect the return magnetic path 8 formed on the insulating layer 6b to the main pole thickening film 5, the insulating layer 6 is formed.
A tapered recess is formed in b. As shown in FIG. 13, the return magnetic path 8 along this surface shape is, for example, N
The i-Fe alloy is formed by a method such as plating. By forming the insulating layer 6b in advance, the coil 7 and the return magnetic path 8 are formed.
And are electrically isolated.

On the return magnetic path 8, as shown in FIG. 14, an electrode 4b paired with the electrode 4a is formed. Electrode 4a
When the electric potential of is the earth potential, a current is passed through the main magnetic pole 2 due to the potential difference between the electric potentials of the electrodes 4a and 4b.

The magnetic head finally has insulating layers 6a, 6 so as to cover the return magnetic path 8 and the electrode 4b shown in FIG.
The insulating layer 6c is formed similarly to b. This insulating layer 6c
The upper surface of is flattened. Further, in order to form a sliding surface facing the recording medium, cutting is performed at a position including the electrode 4a indicated by the alternate long and short dash line.

By this procedure, a current for controlling the magnetic domain structure is applied to the main magnetic pole 2 having a three-layer structure by providing an intermediate layer made of a non-magnetic material between the main magnetic pole magnetic bodies in the signal magnetic flux transmission direction. By flowing the magnetic domain wall even in a narrow track width, and by eliminating the triangular magnetic domain of the magnetic body in the main magnetic pole 2, the effective magnetic permeability in the main magnetic pole 2 can be increased and noise due to the movement of the magnetic wall can be reduced. The magnetic head is for perpendicular magnetic recording, in which waveform distortion is less likely to occur, efficiency is high, and there is no waveform distortion.

Next, a method of manufacturing the single magnetic pole head for perpendicular magnetic recording corresponding to the second embodiment will be briefly described with reference to the sectional views of the essential parts of FIGS. Also in this case, common parts are given the same reference numerals and the description thereof is omitted.

The single magnetic pole head for perpendicular magnetic recording comprises a non-magnetic substrate 1 and at least a main magnetic pole 2 for applying a signal magnetic field to a recording medium, and at least a part of the main magnetic pole 2 is a pair. The magnetic layers 2a and 2b made of a material having a magnetoresistive effect have a three-layer structure with the intermediate layer 2c made of a non-magnetic material interposed therebetween, and a current is supplied in the signal magnetic flux transmission direction of the main magnetic pole 2. Composed.

First, the insulating layer 1a made of Al ₂ O ₃ or the like is formed on the nonmagnetic substrate 1 such as Al ₂ O ₃ —TiC. As shown in FIG. 16, the insulating layer 1a is provided with steps so as to reduce the film thickness on the sliding surface side facing the recording medium. The step is formed by using, for example, a resist formed by a photolithography process as a mask and a physical treatment such as ion milling or a chemical treatment such as reactive ion etching. In particular, the side surface 1b is tapered. In order to form a taper, for example, in the case of ion milling, the method of adjusting the ion incident angle and the like and operating the shape of the resist edge by applying heat, or in the case of reactive ion etching, adjusting the etching gas pressure and the like by applying heat A method such as edge shape manipulation is applied. The return magnetic path 8a is formed on the insulating layer 1a having this step. The return magnetic path 8a is formed by plating Ni-Fe, for example.

A step is buried on the return magnetic path 8a by using a nonmagnetic insulator made of the same material as that of the insulating layer 1a, and the insulating layer 1c is formed to have a film thickness of at least the step 1b or more of the return magnetic path 8a.
Is formed. Then, as shown in FIG. 17, the insulating layer 1c is flattened by polishing or the like until the surface of the return magnetic path 8a is exposed.

Next, the reproducing magnetic path 9 is formed on the flattened surface (see FIG. 18). This reproducing magnetic path 9
The short-circuit magnetic body is formed by using a short-circuit magnetic body, and the short-circuit magnetic body is required to have a film thickness setting that does not saturate during reproduction but saturates during recording.

After the process of forming the reproducing magnetic path 9, the main magnetic pole 2 having a three-layer structure of the pair of magnetic layers shown in FIG. 19 is formed. The main magnetic pole 2 is formed so as to cover a part of the reproducing magnetic path 9. As a result, a step is also formed in the reproducing magnetic path 9. As the main magnetic pole magnetic body having a magnetoresistive effect, for example, a Ni-Fe alloy and a Ni-Fe-Co alloy having a high resistance change rate can be used for the main magnetic pole 2, and magnetic anisotropy in the track width direction can be used. It is formed by applying. For the non-magnetic intermediate layer of the main pole 2, a non-magnetic metal such as Cr, Ag, Mo, Ti, W, Ta or a non-magnetic material such as Al ₂ O ₃ or SiO ₂ is used.

After forming the main pole 2, a thin film of the insulating layer 1d having a uniform thickness is formed on the entire surface. Further, in the bias conductor forming step, as shown in FIG. 20, the bias conductor 10 is formed on the insulating layer 1d in a region that does not overlap the reproducing magnetic path 9.

After forming the bias conductor 10, the insulating layer 1e is formed of an insulating film having a uniform thickness. The thickness of this insulating film is at least thicker than the step formed by the reproducing magnetic path 9.

With this insulating layer 1e, the bias conductor 10
Is insulated. The insulating layer 1e maintains the insulation of the bias conductor 10 while maintaining the area A corresponding to the sliding surface side.
The main magnetic pole 2 is exposed by. Furthermore, the drilling process is shown in FIG.
As shown in FIG. 1, the insulating layer 1e is removed in a tapered shape by performing a process of forming an inclined surface from a position on the opposite side of the sliding surface to a position before the bias conductor 10, for example. In the step of forming the bias return magnetic path, the bias return magnetic path 11 is formed up to the formation start position of the reproducing magnetic path 9 including the region A on the surface thus drilled.

Next, the electrode 4a is formed on the region A in the bias return magnetic path 11 (see FIG. 22).

As the next step, the coil 7 is formed. As shown in FIG. 23, the coil 7 is formed on the insulating layer 1e with a material having a low electric resistivity, such as gold or copper.
The insulating layer 1f forms a layer corresponding to the insulating layer 12b in FIG. 4 so as to completely cover the coil 7.

Next, a part of the insulating layer formed so far is removed and a punching process is performed. This punching process is performed so that an exposed region C of the reproducing magnetic path 9 between the partial region B of the main magnetic pole 2 on the reproducing magnetic path 9 and the formed coil 7 is formed. Bias return magnetic path 11 and each coil 7,
The insulating layer is removed while being tapered so as not to be exposed from the insulating layer. The recording magnetic path 8b is formed in the direction opposite to the sliding surface including the area B to the area C (see FIG. 2).
See 4).

In the next step, the electrode 4b is formed on the recording magnetic path 8b (see FIG. 25).

In the next step, the substrate 1 thus formed
Insulating layer 1g is formed so as to fill the upper irregularities. The surface 1G of the formed insulating layer 1g is flattened by a treatment such as polishing. Further, in order to form a sliding surface facing the recording medium, cutting is performed at a position including the electrode 4a indicated by the alternate long and short dash line (see FIG. 26).

By such a procedure, the efficiency of the bias magnetic field generated by the bias current to the MR element is increased by providing the bias return magnetic body for circulating the bias magnetic field from the sliding surface side of the MR element to the rear part of the MR element. Excuse me. At the same time, by providing the bias return magnetic body, it is possible to reduce the magnetic field applied to the recording medium when the MR element is biased and prevent demagnetization of the recording medium.

Furthermore, by setting the film thickness and the saturation magnetic flux density so that the bias return magnetic material is saturated in the state where an appropriate bias magnetic field is applied to the MR element, the bias current dependency of the bias magnetic field at the bias optimum point. It is loose. Therefore, this magnetic head is a perpendicular magnetic recording single-pole head with low power consumption and little variation.

With the above structure, at least a part of the main magnetic pole has a three-layer structure with a pair of magnetic layers sandwiching an intermediate layer made of a non-magnetic material, and a current flows in the signal magnetic flux transmitting direction of the main magnetic pole. Is supplied to increase the effective magnetic permeability in the main magnetic pole signal magnetic field transmission direction by controlling the magnetic domain structure, and improve the efficiency to a higher output than the conventional output to form a single magnetic pole head for perpendicular magnetic recording. You can

Further, the potential of the electrode on the sliding surface side is set to the ground potential, and a current is passed through the main magnetic pole due to the potential difference from the deep electrode. A single magnetic pole head for perpendicular magnetic recording with less noise is provided while preventing electric breakdown and letting in electric charges escape through the electrodes.

Further, by forming a pair of main magnetic pole magnetic bodies in the main magnetic pole of the three-layer structure with thin films having a magnetoresistive effect, reproduction can be performed by an MR element having a vertical two-layer structure, for example. By providing a high output and a large S / N ratio that does not depend on the relative speed of the magnetic head and the recording medium, and providing a short-circuit magnetic path, it is possible to provide a single magnetic pole head for perpendicular magnetic recording with higher reproduction efficiency.

When recording, the magnetic flux is saturated, and when reproducing, M
By providing a short-circuit magnetic path that quickly guides the magnetic flux that has passed through the R element to the return magnetic path, it is possible to provide a high-output single magnetic pole head for perpendicular magnetic recording with even higher reproduction efficiency.

Further, by providing a bias return magnetic path for circulating a bias magnetic field from the sliding surface side of the MR element to the rear of the MR element, the MR generated by the bias current is generated.
While increasing the efficiency of the bias magnetic field to the device,
The magnetic field applied to the recording medium at the time of biasing the R element can be reduced to prevent demagnetization of the recording medium, and the thickness of the bias return magnetic body is saturated so that the MR element is applied with an appropriate bias magnetic field. By setting the saturation magnetic flux density and the saturation magnetic flux density, the bias current dependency of the bias magnetic field can be moderated at the bias optimum point. Therefore, it is possible to obtain a magnetic head that saves power and has less variation.

[0096]

In the recording / reproducing apparatus according to the present invention, at least a part of the main magnetic pole has a three-layer structure with a pair of magnetic layers sandwiching an intermediate layer made of a non-magnetic material, and a signal magnetic flux of the main magnetic pole. By supplying a current in the transmission direction, the magnetic domain structure is controlled to increase the effective magnetic permeability in the main magnetic pole signal magnetic field transmission direction, resulting in higher efficiency and higher output than the conventional output, and a single magnetic pole for perpendicular magnetic recording. Can be a head.

Further, the potential of the electrode on the sliding surface side is set to the ground potential, and a current is passed through the main magnetic pole due to the potential difference between the electrode and the deep electrode. It is possible to prevent electric breakdown and to escape the jumping charges through the electrodes to form a single magnetic pole head for perpendicular magnetic recording with less noise.

Further, when the pair of main magnetic pole magnetic bodies in the main magnetic pole of the three-layer structure are made of thin films having a magnetoresistive effect, reproduction by, for example, a vertical two-layer structure MR element becomes possible, and further By providing a high output and a large S / N ratio that does not depend on the relative speed of the magnetic head and the recording medium, and providing a short-circuit magnetic path, it is possible to provide a single magnetic pole head for perpendicular magnetic recording with higher reproduction efficiency.

When recording, the magnetic flux is saturated, and when reproducing, M
By providing a short-circuit magnetic path that quickly guides the magnetic flux that has passed through the R element to the return magnetic path, it is possible to provide a high-output single magnetic pole head for perpendicular magnetic recording with even higher reproduction efficiency.

Further, by providing a bias return magnetic path for circulating a bias magnetic field from the sliding surface side of the MR element to the rear portion of the MR element, the MR generated by the bias current is generated.
While increasing the efficiency of the bias magnetic field to the device,
The magnetic field applied to the recording medium at the time of biasing the R element can be reduced to prevent demagnetization of the recording medium, and the thickness of the bias return magnetic body is saturated so that the MR element is applied with an appropriate bias magnetic field. By setting the saturation magnetic flux density and the saturation magnetic flux density, the bias current dependency of the bias magnetic field can be moderated at the bias optimum point. Therefore, it is possible to obtain a magnetic head that saves power and has less variation.

[Brief description of drawings]

FIG. 1 is a diagram showing a cross section of a main part of a first embodiment of a single magnetic pole head for perpendicular magnetic recording according to the present invention.

FIG. 2 is a view showing a cross section of a main part of a tip portion of a single magnetic pole head for perpendicular magnetic recording, which is an enlarged view of the cross section of the main part.

FIG. 3 is a graph showing the relationship between current and magnetic permeability of the single magnetic pole head for perpendicular magnetic recording.

FIG. 4 is a view showing a cross section of a main part of a second embodiment of a single magnetic pole head for perpendicular magnetic recording according to the present invention.

FIG. 5 is a view showing a cross section of a main part of a tip portion of a single magnetic pole head for perpendicular magnetic recording, which is an enlarged view of the cross section of the main part.

FIG. 6 is a schematic view showing a cross section of a main part at the time of forming a main pole in a process of manufacturing the magnetic head of the first embodiment.

FIG. 7 is a schematic view showing a cross section of a main part when a leading end magnetic path is formed in a process of manufacturing the magnetic head.

FIG. 8 is a schematic view showing a cross section of a main part when an electrode is formed in a process of manufacturing the magnetic head.

FIG. 9 is a schematic view showing a cross section of a main part when a main magnetic pole thick film is formed in a process of manufacturing the magnetic head.

FIG. 10 is a schematic view showing a cross section of a main part when an insulating layer is formed in a step of manufacturing the magnetic head.

FIG. 11 is a schematic view showing a cross section of a main part when a coil is formed in a process of manufacturing the magnetic head.

FIG. 12 is a schematic view showing a cross section of a main part when an insulating layer is formed after forming a coil in a process of manufacturing the magnetic head.

FIG. 13 is a schematic view showing a cross section of a main part when a return magnetic path is formed in a step of manufacturing the magnetic head.

FIG. 14 is a schematic view showing a cross section of a main part when an electrode is formed on the return magnetic path in the process of manufacturing the magnetic head.

FIG. 15 is a schematic view showing a cross section of a main part relating to flattening by an insulating layer and cutting of a sliding surface in a process of manufacturing the magnetic head.

FIG. 16 is a schematic view showing a cross section of a main part at the time of forming a return magnetic path in the process of manufacturing the magnetic head of the second embodiment.

FIG. 17 is a schematic view showing a cross section of a main part at the time of insulation and flattening processing in the process of manufacturing the magnetic head.

FIG. 18 is a schematic view showing a cross section of a main part when a reproducing magnetic path is formed in a process of manufacturing the magnetic head.

FIG. 19 is a schematic view showing a cross section of a main part when a main pole is formed in a process of manufacturing the magnetic head.

FIG. 20 is a schematic view showing a cross section of a main part when a bias conductor is formed in a step of manufacturing the magnetic head.

FIG. 21 is a schematic view showing a cross section of a main part when a bias return magnetic path is formed in a process of manufacturing the magnetic head.

FIG. 22 is a schematic view showing a cross section of a main part at the time of forming electrodes in the process of manufacturing the magnetic head.

FIG. 23 is a schematic view showing a cross section of a main part at the time of insulation treatment after coil formation in the process of manufacturing the magnetic head.

FIG. 24 is a schematic view showing a cross section of a main part when a recording magnetic path is formed in a process of manufacturing the magnetic head.

FIG. 25 is a schematic view showing a cross section of a main part when an electrode is formed on a recording magnetic path in a process of manufacturing the magnetic head.

FIG. 26 is a schematic view showing a cross section of a main part regarding flattening by an insulating layer and cutting of a sliding surface in a process of manufacturing the magnetic head.

FIG. 27 is a conceptual diagram showing track dependence of a magnetic domain structure in a single magnetic pole head for perpendicular magnetic recording.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Substrate 1a, 1c to 1g, 6a, 6b, 12a, 12b Insulating layer 2 Main magnetic poles 2a, 2b Magnetic material layer (or magnetic material having magnetoresistive effect) 2c Intermediate layer (non-magnetic material) 3 Tip magnetic guide path 4a 4b electrode 5 main pole thickening film 7 coil 8 and 8a return magnetic path 8b recording magnetic path 9 reproducing magnetic path 10 bias conductor 11 bias return magnetic path

Claims (6)

[Claims] 1. A main magnetic pole, which receives at least a signal magnetic field from a recording medium, is formed on a non-magnetic substrate, and at least a part of the main magnetic pole comprises a pair of magnetic layers and an intermediate layer made of a non-magnetic material. Through a three-layer structure,
A single magnetic pole head for perpendicular magnetic recording, wherein a current is supplied in a signal magnetic flux transmission direction of the main magnetic pole. 2. The single magnetic pole head for perpendicular magnetic recording according to claim 1, wherein an auxiliary magnetic pole is provided as a return magnetic path magnetically coupled to the rear end side of the main magnetic pole. 3. A magnetic material layer constituting the main pole is at least partially formed of a magnetic material having a magnetoresistive effect, and a signal recorded on the recording medium is reproduced by the magnetoresistive effect of the magnetic material. The single magnetic pole head for perpendicular magnetic recording according to claim 1, wherein 4. The single magnetic pole for perpendicular magnetic recording according to claim 1, wherein on the main magnetic pole, an electrode on the sliding surface side for passing a current through the magnetic body of the main magnetic pole is grounded. head. 5. The recording is performed by forming a reproducing magnetic path for circulating a magnetic field from the recording medium by short-circuiting a recording magnetic path formed in the magnetoresistive effect element in a direction opposite to a sliding surface side of the recording medium. The single magnetic pole head for perpendicular magnetic recording according to claim 3, wherein the reproduced signal is reproduced. 6. A return magnetic path is provided on the front end side of the main magnetic pole for returning a bias magnetic field applied to the magnetoresistive effect element from a magnetic path leading to the front end side. The single magnetic pole head for perpendicular magnetic recording according to 3 or 5.