JPH10320720A - Magnetic head for perpendicular recording - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a perpendicular magnetic recording magnetic head capable of recording the magnetization of a medium so that the steep reproducing waveform is obtainable and also capable of reducing the influence of crosstalk. SOLUTION: This perpendicular recording magnetic head is formed in such a manner that the MR head 50 for reproduction and a magnetic induction head 10 for recording are laminated. The MR head 50 is composed of a lower shield 54, reproducing gap 56, MR element 58, common pole 60, etc. The magnetic induction head 10 is composed of the common pole 60, recording gap 62, exciting coil, trailing pole 12, etc. On the trailing pole 12, the end surface 12a at the side opposite to the side of MR head 50 is flattened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a perpendicular recording magnetic head used in a magnetic recording / reproducing apparatus employing a perpendicular magnetization system, and more particularly to a perpendicular double-layered medium having a perpendicular magnetic layer and a soft magnetic underlayer. And a magnetic head for perpendicular recording.

[0002]

2. Description of the Related Art Since a perpendicular magnetization system has a higher recording resolution than a longitudinal magnetization system, it is expected to be put to practical use with the recent increase in magnetic recording density. Conventionally, in a perpendicular magnetic recording / reproducing apparatus using a perpendicular double-layer film medium,
A perpendicular recording magnetic head having an MR head in a reproducing unit and a magnetic induction type head in a recording unit is used. The conventional magnetic head for perpendicular recording is described in, for example, “Journal of the Japan Society of Applied Magnetics Vol. 19 Supplement No. S2.
PP122-125 ", and has the same structure as that used in the longitudinal recording method.

FIGS. 5 and 6 show a conventional magnetic head for perpendicular recording. FIG. 5 is a bottom view as viewed from a medium sliding surface, and FIG. 6 is a longitudinal sectional view. Hereinafter, description will be made based on these drawings.

The conventional magnetic head for perpendicular recording has a structure in which an MR head 50 for reproduction and a magnetic induction type head 52 for recording are laminated. The MR head 50 includes a lower shield 54, a reproducing gap 56, an MR element 58, a common pole 60, and the like. Magnetic induction type head 52
Are the common pole 60, the recording gap 62, the exciting coil 6
4, the trailing pole 66 and the like. In FIG. 6, the recording medium moves from right to left along the lower end of the perpendicular recording magnetic head.

When recording is performed on a longitudinal medium using this perpendicular recording magnetic head, the recording magnetic field generated from the end face 66b of the trailing pole 66 on the MR head 50 side (tip side) determines the medium recording magnetization. . On the other hand, when recording is performed on a perpendicular double-layer film medium using this perpendicular recording magnetic head, the recorded magnetization distribution is the end face of the trailing pole 66 on the opposite side (rear end side) of the MR head 50 side. 66
It is determined by the recording magnetic field generated from a.

[0006] As shown in FIG.
The end face 66b on the tip end side of No. 6 has a substantially rectangular shape when viewed from the medium sliding surface. On the other hand, the trailing end surface 66a of the trailing pole 66 is not a flat surface when viewed from the medium sliding surface. Therefore, when recording is performed on a perpendicular double-layer film medium, the shape of the recording magnetization transition is changed to the end face 66.
It does not become flat according to the shape of a.

When the perpendicular recording magnetic head is used for a longitudinal recording medium, side erase bands (non-information recording tracks) exist at both ends of the recording tracks. The side erase band has an effective role in reducing the influence of so-called crosstalk in reproducing erroneous information from an adjacent track during signal reproduction.

However, the perpendicular double-layer film medium has a very high recording resolution, so that the magnetization reversal part is steep, so that a side erase band is hardly observed.

[0009]

When recording is performed on a perpendicular double-layered medium using a conventional perpendicular recording magnetic head,
The following problems arise.

[0010] The first problem is that the shape of the magnetization transition is not linear. Therefore, no matter how the perpendicular double-layer film medium having a high recording resolution is used, the pulse width of the reproduced waveform is widened. This makes it difficult to obtain a clear recording magnetization distribution, especially in a high recording density region, so that good recording / reproducing characteristics cannot be obtained. The reason is that the end face 66a on the trailing end side of the trailing pole 66, which determines the medium recording magnetization when a perpendicular double-layer film medium is used,
Is not flat.

The second problem is that the influence of crosstalk from adjacent recording tracks or previous recording tracks is large. The crosstalk component becomes noise at the time of reproduction, leading to a reduction in error rate. The reason is that the perpendicular double-layer film medium does not have a side erase band at the end of the recording track, and thus reproduces erroneous information from an adjacent recording track or a previous recording track.

[0012]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to improve the characteristics of a perpendicular magnetization type magnetic recording / reproducing apparatus, and to enable recording of medium magnetization so as to obtain a steep reproducing waveform and to reduce the influence of crosstalk. An object of the present invention is to provide a magnetic head for perpendicular magnetic recording.

[0013]

A perpendicular recording magnetic head according to the present invention comprises an MR head for reproduction and a magnetic induction type head for recording. The trailing pole of the magnetic induction type head has a flattened end face opposite to the MR head. This trailing pole may have a flattened end face opposite to the MR head side made of a high magnetic flux density film, or may be made entirely of a high magnetic flux density material. The shape of the trailing pole viewed from the medium sliding surface is the M
It may be trapezoidal with the end face on the R head side as the base.

[0014]

FIG. 1 is a bottom view of a perpendicular recording magnetic head according to a first embodiment of the present invention, as viewed from a medium sliding surface. Hereinafter, description will be made based on this drawing.

The magnetic head for perpendicular recording according to the present embodiment comprises an MR head 50 for reproduction and a magnetic induction type head 10 for recording.
Are laminated. The MR head 50 includes a lower shield 54, a reproducing gap 56, an MR element 58, a common pole 60, and the like. The magnetic induction type head 10 includes a common pole 60, a recording gap 62, an exciting coil 64 (FIG. 2), a trailing pole 12, and the like. The trailing pole 12 has an end surface 12a on the opposite side (rear end side) of the MR head 50 side (front end side) flattened.

A method for manufacturing the magnetic head for perpendicular recording will be described. First, from the lower shield 54 to the trailing pole 12 are formed on the non-magnetic substrate in order.
After the formation of the trailing pole 12, the trailing end 12a of the trailing pole 12 is flattened so as to be parallel to the MR element 58 and the like. This flattening is performed by lapping (polishing), FIB (focused ion beam) processing, or the like.

FIG. 2 is a longitudinal sectional view of the magnetic head for perpendicular recording of FIG. Hereinafter, a case in which recording is performed on a perpendicular double-layer film medium with the perpendicular recording magnetic head will be described with reference to FIGS.

The perpendicular double layer medium 20 includes a recording magnetic layer 22,
It is composed of a backing soft magnetic layer 24 and the like. The recording magnetic field is generated from the entire end surface 12 b on the tip side of the trailing pole 12, passes through the recording magnetic layer 22, and forms the soft magnetic layer 2.
It turns out that it flows to 4. The perpendicular recording magnetic head runs from left to right in FIG. Therefore, the recording magnetization recorded on the perpendicular double-layered film medium 20 is determined by the magnetic field generated from the end face 12 a on the trailing end of the trailing pole 12. In the perpendicular recording magnetic head of the present embodiment, the trailing end surface 12 of the trailing pole 12
Since a is flattened, the shape of the recording magnetization transition portion of the perpendicular double-layered film medium 20 can be made linear. By making the magnetization transition portion linear, the pulse width of the isolated reproduction waveform can be narrowed. Furthermore, by making the magnetization transition part linear,
Good recording can be performed even if the magnetization transition interval is narrowed, whereby good recording / reproducing characteristics can be obtained in a high-density region.

FIG. 3 is a bottom view of the second embodiment of the magnetic head for perpendicular recording according to the present invention, as viewed from the medium sliding surface. Hereinafter, description will be made based on this drawing. However, the same parts as those in FIG.

In this embodiment, the magnetic induction type head 3
The zero trailing pole 32 is composed of two layers, a high magnetic flux density film 34 and a normal magnetic pole film 36. High magnetic flux density film 34
Is made of an Fe-based high magnetic flux density material, and has a rear end face 3
2a is flattened. In addition, trailing pole 3
2 may be replaced by the high magnetic flux density film 34.

In the same manner as described in the first embodiment, the recording magnetization of the medium is controlled by the trailing end surface 3 of the trailing pole 32.
It is determined by the recording magnetic field generated from 2a. By arranging the high magnetic flux density film 34 on the trailing end side of the trailing pole 32, it is possible to perform recording on the medium with a stronger recording magnetic field. Therefore, the same effect as in the first embodiment can be obtained even in a perpendicular double-layered medium having a high coercive force of the medium recording magnetic film.

Next, a third embodiment of the magnetic head for perpendicular recording according to the present invention will be described with reference to FIG.

In the magnetic head for perpendicular recording according to this embodiment,
As shown in FIG. 1, the shape of the trailing pole 12 viewed from the medium sliding surface is a trapezoidal shape with the end surface 12 b on the MR head 50 side as the base. Trailing pole 12
Of the trailing pole 12 is defined by the azimuth angle θ of the both side surfaces 12 c and 12 d of the trailing pole 12. The trapezoid is formed by etching or FIB processing.

FIG. 4 is a schematic diagram showing a recording track pattern when recording is performed on a perpendicular double-layer film medium by the magnetic head for perpendicular recording according to the present embodiment. Hereinafter, description will be made with reference to FIGS.

The recording track 38 is composed of a signal recording track 40 recorded by the trailing end surface 12a of the trailing pole 12 and the both side surfaces 1 of the trailing pole 12.
Side recording track 42 recorded by 2c and 12d
And can be separated into Since the recording pattern of the side recording track 42 is not parallel to the MR element 58 for reproduction, the recording information of the side recording track 42 is greatly reduced due to azimuth loss. As a result, the side recording track 42 corresponds to a non-signal recording track. Here, the azimuth angle θ is set to 4 so as to receive a sufficient azimuth loss.
0 degree or more.

With the side recording track 42, the recording track 38 is always recorded while being separated from the adjacent recording track (or the previous recording track) 44. As a result, it is possible to reduce the influence of crosstalk that erroneously reproduces a signal from the adjacent recording track (or previous track) 44. Also, the track width t of the side recording track 42
Can be arbitrarily changed depending on the azimuth angle θ and the film thickness h of the trailing pole 12. As a result, the side recording tracks 4 can be adjusted according to the specifications of the magnetic disk drive.
2 can be arbitrarily set.

Conventionally, to avoid the influence of crosstalk,
The design is such that the track width of the MR element 58, which is the reproduction track width, is smaller than the recording track width. On the other hand, in the present embodiment, by providing the side recording track 42, the track width of the MR element 58 can be made equal to or larger than the recording track. In general, the reproduction output is proportional to the reproduction track width. Therefore, a higher reproduction output can be obtained by using the perpendicular recording magnetic head of the present embodiment.

[0028]

The first effect is that the magnetization transition region of the medium can be made linear. The reason for this is that the end face on the trailing end side of the trailing pole, which had not been subjected to any processing in the past, was flattened. As a result, uniform and steep recording magnetization can be recorded in the track width direction, and a favorable recording magnetization state can be obtained even in a high-density region where the interval between magnetization transitions is narrow. Therefore, good recording / reproducing characteristics can be obtained in a high density region.

The second effect is that the first effect can be obtained even when a high coercive force medium is used as a recording medium. The reason for this is that by laminating a high magnetic flux density film on the trailing end side of the trailing pole or by using a high magnetic flux density material for the entire trailing pole, it is possible to perform recording on the medium with a stronger recording magnetic field. .

The third effect is that the effect of crosstalk can be reduced. The reason for this is that a side recording pattern that does not become a signal component is recorded at both ends of a recording track by using a structure in which azimuth angles are provided on both side surfaces of the trailing pole. Since the signal recording track is separated from the adjacent recording track or the previous recording track by the side recording track, the influence of crosstalk can be reduced. Thereby, high S /
The N signal can be reproduced, and good recording / reproducing characteristics can be obtained.

[Brief description of the drawings]

FIG. 1 is a bottom view of a first embodiment of a magnetic head for perpendicular recording according to the present invention, as viewed from a medium sliding surface.

FIG. 2 is a longitudinal sectional view of the perpendicular recording magnetic head of FIG. 1;

FIG. 3 is a bottom view showing a second embodiment of the magnetic head for perpendicular recording according to the present invention, as viewed from a medium sliding surface.

FIG. 4 is a schematic diagram showing a recording track pattern when recording is performed on a perpendicular double-layer film medium by the perpendicular recording magnetic head of FIG. 1;

FIG. 5 is a bottom view showing a conventional perpendicular recording magnetic head viewed from a medium sliding surface.

FIG. 6 is a longitudinal sectional view of the perpendicular recording magnetic head of FIG. 5;

[Explanation of symbols]

 50 MR head 10, 30 Magnetic induction type head 12, 32 Trailing pole 12a, 32a Flattened end face

Claims (4)

[Claims] 1. A perpendicular recording magnetic head in which an MR head for reproduction and a magnetic induction type head for recording are stacked, wherein the trailing pole of the magnetic induction type head is M
A perpendicular recording magnetic head, wherein an end surface opposite to the R head is flattened. 2. The perpendicular recording magnetic head according to claim 1, wherein the trailing pole has a flattened end face opposite to the MR head and made of a high magnetic flux density film. 3. The perpendicular recording magnetic head according to claim 1, wherein the trailing pole is entirely made of a high magnetic flux density material. 4. The perpendicular recording magnetic head according to claim 1, wherein the shape of the trailing pole viewed from the medium sliding surface is a trapezoid having an end face on the MR head side as a base.