JPH0445886B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a magnetic head that performs recording or reproduction perpendicularly to a recording medium.

Conventional configurations and their problems Perpendicular magnetization recording has been proposed as a method for performing high-density magnetic recording (for example,
134706, JP-A-53-3209). This method has the feature that the demagnetizing field of the recorded magnetization is small and enables high-density magnetic recording, but it requires a recording medium with perpendicular anisotropy and a perpendicular magnetic recording head with a strong perpendicular magnetic field. shall be. 1st
The figure shows an example of a conventional perpendicular magnetic recording head. A magnetic recording medium 3 having a medium high permeability layer 2 under a magnetization layer 1 having perpendicular magnetic anisotropy
A main magnetic pole 6 in which a high magnetic permeability thin film 4 is sandwiched between non-magnetic materials 5 is provided in close proximity to the magnetized layer 1, and a coil 7 is wound around the main magnetic pole 6 to provide electrical input or output for perpendicular magnetic recording or Perform playback. In the conventional head with this configuration, the recording medium is formed by the magnetic flux passing through the magnetic circuit 8 formed by the current flowing through the coil 7, and the magnetic layer 1 is
A portion close to the high magnetic permeability thin film 4 is magnetized and recorded. Conversely, during reproduction, the magnetic flux due to the magnetization of the portion of the magnetic layer 1 that is close to the high magnetic permeability thin film 4 flows through the magnetic circuit 8, interlinks the coil 7, and is output from the coil 7 as an electrical signal. . Here, in the conventional magnetic head, since the magnetic circuit 8 has a large magnetic resistance, the conventional magnetic head has a disadvantage of poor efficiency both during recording and reproduction. There are three reasons why the magnetic resistance increases. The first is that the high magnetic permeability thin film 4 is generally thick.
This is because although it is thin at about 1 μm, it is several mm long, so even if it is made of a high magnetic permeability material such as permalloy, the magnetic resistance will be large. The second reason is that the magnetic circuit 8 is formed from the high magnetic permeability conjunctiva 4 to the medium high magnetic permeability layer 2 through air with low magnetic permeability, so that the magnetic resistance increases. Furthermore, the third cause is that the thickness of the medium high magnetic permeability layer 2 is 1 μm or less and the length of the portion that becomes part of the magnetic circuit 8 is several mm, which increases the magnetic resistance.

As mentioned above, conventional perpendicular magnetic recording heads have a drawback of high magnetic resistance, which has the drawback of poor recording or reproducing efficiency.

OBJECTS OF THE INVENTION The present invention is intended to eliminate the above-mentioned conventional drawbacks, and an object of the present invention is to provide a magnetic head with greatly improved recording or reproducing efficiency.

Structure of the Invention The present invention achieves the above object, and includes providing a high permeability magnetic thin film in close proximity to a magnetic recording medium having a high permeability layer under a magnetization layer having perpendicular magnetic anisotropy. A main magnetic pole having a structure in which a portion of a magnetic thin film close to the magnetization layer is sandwiched by at least a non-magnetic material, and has at least a first high magnetic permeability material magnetically connected to the high permeability magnetic thin film. a second high magnetic permeability body provided close to or connected to the main magnetic pole; and a third high magnetic permeability body provided on the opposite side of the main magnetic pole with the magnetic recording medium in between. Sd is the area of the opposing portions of the first high magnetic permeability body and the high magnetic permeability layer, d is the average distance between the first high magnetic permeability body and the high magnetic permeability layer, and the second and high magnetic permeability layers are The area of the opposing portion of the third high magnetic permeability body is Su, the average distance between the second and third high magnetic permeability body is u, and the area of the opposing portion of the first and second high magnetic permeability body is When the area is Sv and the average distance between the first and second high magnetic permeability bodies is v, it is configured such that d/Sd>u/Su, d/Sd>v/Sv. The present invention provides a magnetic head with

DESCRIPTION OF EMBODIMENTS Examples of the present invention will be described below with reference to the drawings.

FIG. 2 shows a sectional view of a magnetic head according to an embodiment of the present invention, and the same parts as in FIG. 1 are designated by the same numbers.

In this embodiment, a high magnetic permeability thin film 4 is provided adjacent to a magnetic recording medium 3 consisting of a magnetic layer 1 and a medium high magnetic permeability layer 2, and a first high magnetic permeability block 10 is provided connected to a part of the thin film 4. , a main magnetic pole 6 including a tip portion 17 sandwiched between non-magnetic materials 5 is provided at a portion of the high magnetic permeability thin film 4 near the magnetic recording medium 2 . A second high magnetic permeability block 11 is placed adjacent to the main magnetic pole 6 on the magnetic recording medium 3.
Provided on the main magnetic pole 6 side. Furthermore, a third high magnetic permeability block 12 is provided on the opposite side of the main magnetic pole 6 of the magnetic recording medium 3.
will be established. A coil 7 is wound around the main pole 6.

FIG. 3 is an enlarged view of the main pole tip 17 of the magnetic head shown in FIG. In Figure 3, the first
The area of the opposing portions of the high magnetic permeability body 10 and the high magnetic permeability layer 2 is Sd, the average distance between the two is d, and the opposing portion of the second high magnetic permeability body 11 and the third high magnetic permeability body 12 is Sd. The area of is Su, the average distance between the two is u, the area of the opposing portion of the first high magnetic permeability body 10 and the second high magnetic permeability body 11 is Sv, and the average distance between the two is v
The configuration is such that d/Sd>u/Su, d/Sd>v/Sv.

The effects of this embodiment with such a configuration will be described. By providing the first high magnetic permeability block 10 magnetically connected to the high magnetic permeability thin film 4, the magnetic resistance of the high magnetic permeability thin film 4 can be significantly reduced.
Furthermore, by providing the second high magnetic permeability block 11 near or connected to the main magnetic pole 6 on the main magnetic pole 6 side of the magnetic recording medium 3, a magnetic circuit 13 is formed, and the magnetic circuit 13 can pass through the air. There was no magnetic resistance, and the magnetic resistance could be significantly reduced. Furthermore, by providing the third high magnetic permeability block 12 on the opposite side of the main magnetic pole 6 of the magnetic recording medium 3, the magnetic circuit 1
3 can shorten the distance through the medium high permeability layer 2,
The effect of significantly lowering the magnetic resistance of the medium high permeability layer 2 was obtained.

Further, as shown in FIG. 3, in this embodiment, in order for the magnetic flux from the medium to sufficiently interlink with the coil 7 during reproduction, the magnetic circuit 20 that interlinks the coil 7 is replaced by a magnetic circuit 21 that does not interlink the coil 7. It is desirable that the magnetic resistance be lower. For this purpose, the magnetic reluctance between the first high permeability block 10 and the medium high permeability layer 2 must be greater than the magnetic reluctance between the second high permeability block 11 and the third high permeability block 12. The condition is that it is large. Since magnetic resistance is proportional to the distance of the magnetic path and inversely proportional to the area, the area of the first high magnetic permeability block 10 facing the medium high magnetic permeability layer 2 is Sd, the average distance is d, and the second high magnetic resistance is Assuming that the area of the facing portion of the magnetic permeability block 11 and the third high magnetic permeability block 12 is Su, and the average distance is u, the above condition is satisfied by setting d/Sd>u/Su.

Similarly, the magnetic resistance between the first high magnetic permeability block 10 and the medium high magnetic permeability layer 2 is larger than the magnetic resistance between the first high magnetic permeability block 10 and the second high magnetic permeability block 11. This is also a condition. For this purpose, it is necessary to set d/Sd>v/Sv.

Note that the second high magnetic permeability block 11 is connected to the main magnetic pole 6.
It is sufficient that the non-magnetic material 5 has a structure in which at least the tip portion of the high-permeability thin film 4, which is close to the magnetic recording medium 3, is sandwiched therebetween.

The above-described combination of structures for reducing magnetic resistance makes it possible to significantly reduce the overall magnetic resistance, and the efficiency of the head is greatly improved in both recording and reproduction. Specifically, the high magnetic permeability thin film 4 is made of an amorphous material whose main components are Co and Zn, which have higher saturation magnetization and higher magnetic permeability, such as CoZrNb or CoFeZrNb, in addition to the conventionally used permalloy.
The length of the main pole tip portion 17 is determined by sputtering an amorphous material of about 1 μm such as
The thickness should be approximately 100μm. First high permeability block 1
0 is made of ferrite material, etc., and has a thickness of 100 μm.
The length is about 5 mm. Second high permeability block 1
Block 1 is made of ferrite material or the like and is sufficiently larger than the first high magnetic permeability block 10 to reduce the magnetic resistance of the space. The third high magnetic permeability block 12 on the rear surface of the medium also has a large surface facing the second high magnetic permeability block 11 to reduce magnetic resistance, and is made of ferrite material or the like.

Effects of the Invention In summary, the present invention provides a high permeability magnetic thin film in close proximity to a magnetic recording medium having a high permeability layer under a magnetic layer having perpendicular magnetic anisotropy, and a main magnetic pole having a structure in which a portion adjacent to the magnetization layer is sandwiched by at least a non-magnetic material and has at least a first high magnetic permeability material magnetically connected to the high magnetic permeability magnetic thin film; A second high magnetic permeability body provided adjacent to or connected to the first high magnetic permeability body, and a third high magnetic permeability body provided on the opposite side of the main magnetic pole with the magnetic recording medium in between. The area of the opposing portion of the magnetic permeability body and the high magnetic permeability layer is Sd, the average distance between the first high magnetic permeability body and the high magnetic permeability layer is d, and the second and third
The area of the opposing parts of the high magnetic permeability bodies is Su, the average distance between the second and third high magnetic permeability bodies is u, and the area of the opposing parts of the first and second high magnetic permeability bodies is
Sv, when the average distance between the first and second high magnetic permeability bodies is v, d/Sd>u/Su, d/Sd>v/Sv. The magnetic head has the advantage of lowering the resistance of the magnetic circuit of the magnetic head and increasing the recording or reproducing efficiency.

[Brief explanation of drawings]

Figure 1 is a sectional view of a conventional perpendicular magnetic recording head, Figure 2 is a sectional view of a magnetic head according to an embodiment of the present invention, and Figure 3 is an enlarged view of the tip of the main pole showing the optimal structure of this embodiment. It is a diagram. 1...Magnetization layer, 2...Medium high permeability layer, 3...
Magnetic recording medium, 4... High magnetic permeability thin film, 5... Nonmagnetic material, 6... Main magnetic pole, 7... Coil, 8, 13,
20... Magnetic circuit, 10... First high magnetic permeability block, 11... Second high magnetic permeability block, 12...
...Third high magnetic permeability block, 17... Main magnetic pole tip portion.

Claims (1)

[Scope of Claims] 1. A high permeability magnetic thin film is provided adjacent to a magnetic recording medium having a high magnetic permeability layer under a magnetization layer having perpendicular magnetic anisotropy, and the magnetization of the high permeability magnetic thin film is a main magnetic pole having a structure in which a portion adjacent to the layer is sandwiched by at least a non-magnetic material and has at least a first high magnetic permeability material magnetically connected to the high magnetic permeability magnetic thin film; and a main magnetic pole adjacent to the main magnetic pole. or a second high magnetic permeability body provided in connection with the second high magnetic permeability body and a third high magnetic permeability body provided on the opposite side of the main magnetic pole with the magnetic recording medium in between; The area of the opposing parts of the high magnetic permeability body and the high magnetic permeability layer is
Sd, the average distance between the first high magnetic permeability body and the high magnetic permeability layer, d, the area of the opposing portions of the second and third high magnetic permeability bodies, Su, the second and third heights. The average distance between the magnetic permeability bodies is u, the area of the opposing portions of the first and second high magnetic permeability bodies is Sv, and the first
A magnetic head characterized in that it is constructed such that d/Sd>u/Su, d/Sd>v/Sv, where v is the average distance between the magnetic head and the second high magnetic permeability body. 2. The magnetic head according to claim 1, wherein the high magnetic permeability thin film is made of an amorphous material containing Co and Zr as main components. 3. The magnetic head according to claim 1, wherein the high magnetic permeability thin film is made of an amorphous material containing Co, Fe, Zr, and Nb.