JPH0448424A - Magnetic head and manufacture of the same - Google Patents

Abstract

PURPOSE:To prevent a crosstalk from generating in plural adjacent magnetic domains on a recording medium by making a main magnetic pole almost circular arc corrdsponding to the shape of the magnetic domain on the recording medium. CONSTITUTION:A reproduction head pat 16 is equipped with a projecting part 25 (bent part) bent circular-arcuately, which is formed on the outside face of a non-magnetic substance and a magnetic core 20 as base materials. A main magnetic pole 26 constituted of a thin film is formed on this projecting part 25, and a protective layer 27 is formed on the main magnetic pole 26. Then, the main magnetic pole 26 is almost circular arc corresponding to the shape of the magnetic domain on the recording medium. Therefore, the crosstalk is prevented from generating in the plural adjacent magnetic domains on the recording medium, and the sufficient output of a regenerative signal can be obtained. Thus, an accurate reproduction can be realized even when he magnetic domains are almost in circular arc as a result that recording density is heightened at an optical assisting magnetic recording.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to the recording and/or recording of optically assisted magnetically recorded information.
The present invention also relates to a magnetic head used for reproduction and a method for manufacturing the same.

[Conventional technology]

In recent years, magneto-optical disks have been developed as recording media on which information can be recorded, reproduced, and erased. Magneto-optical disks usually use a perpendicularly magnetized film, and apply an external magnetic field to the perpendicularly magnetized film in a direction perpendicular to the film surface while the temperature is raised by irradiation with laser light to lower the coercive force. This allows the direction of magnetization to match the direction of the external magnetic field to record information. On the other hand, during reproduction, information is detected based on the phenomenon that when the perpendicularly magnetized film is irradiated with laser light, the direction of rotation of the polarization plane of the reflected light differs depending on the direction of magnetization due to the so-called magneto-optic effect. will be held.

Recording methods for magneto-optical disks can be roughly divided into optical modulation methods, in which the intensity of laser light is modulated according to the information to be recorded while continuously applying an external magnetic field in a fixed direction, and laser light with a constant intensity. There is a magnetic field modulation method that reverses the direction of the external magnetic field depending on the information to be recorded while irradiating the external magnetic field. The above-mentioned magnetic field modulation method is considered to be a promising method for realizing override in which new information is directly recorded without erasing old information when rewriting recorded information.

In this magnetic field modulation method, if the rotational speed of the disk or the frequency of magnetic field modulation is increased in order to improve the recording density, as shown in Figure 4, the recording magnetic domain length will be smaller than the spot diameter of the laser beam on the disk. It is possible to reduce the recording pit size to as small as 0.3 μm.
It is known that the magnetic domains formed by ... are arc-shaped or crescent-shaped (see 13th Japanese Society of Applied Magnetics Academic Lecture Abstracts (1989), p. 198).

[Problems to be Solved by the Invention] However, as described above, when the recording pits 1... become arcuate and the magnetic domain length becomes short, when reproducing this with a laser beam, the laser bond is Since the beam is irradiated across recording pits 1, . . ., there is a problem in that individual recording bits 1 cannot be reproduced.

Therefore, it is conceivable to magnetically reproduce the information in the recording pits 1 using a magnetic head without using laser light. However, in this case, since the recording pits 1 are arcuate, crosstalk is likely to occur between adjacent recording pits 1 during playback, and the reproduction signal output also decreases, making accurate reproduction impossible. It is.

[Means to solve the problem]

In order to solve the above-mentioned problems, a magnetic head according to the present invention is a magnetic head used for recording and reproducing information recorded in substantially arc-shaped magnetic domains on a recording medium by optically assisted magnetic recording. , a main magnetic pole consisting of a thin film core formed on a base material and having an almost circular arc shape that is almost the same as the shape of the magnetic domain when viewed from the recording medium side, a reproducing coil provided around the main magnetic pole, and a main magnetic pole. The recording coil is provided in the return path section of the magnetic flux from the magnetic head.

In manufacturing the above magnetic head, after forming a curved portion having a substantially circular arc shape on the base material by etching, a main magnetic pole consisting of a thin film core is formed on the base material, and a reproducing layer is formed on the main magnetic pole. It is preferable to provide a recording coil in the return path section as well as a recording coil in the return path section.

[Function] In the magnetic head of the present invention described above, the magnetic flux from the magnetic domain on the recording medium is guided to the main magnetic pole, and a voltage is induced between the terminals of the reproducing coil in response to a change in the magnitude of this magnetic flux. is,
Information is detected based on this. In this case, since the main magnetic pole has an almost arc shape that corresponds to the shape of the magnetic domain on the recording medium, crosstalk does not occur between multiple adjacent magnetic sections on the recording medium, and a sufficient reproduction signal is generated. You will be able to get the output. As a result of increasing the recording density in optically assisted 1-1 recording, accurate reproduction can be performed even when the magnetic domain has a substantially arcuate shape.

Furthermore, since a recording (or erasing) coil is provided in the return bus section, recording (or erasing) and reproduction can be performed using the same magnetic head, thereby simplifying the configuration.

On the other hand, according to the method for manufacturing the magnetic head described above, first,
After forming a curved portion on the base material in a shape corresponding to the magnetic domain on the recording medium, which is in the shape of an arc, the main magnetic pole was formed with a thin film on the base material, so that the magnetic domain on the recording medium It becomes possible to form a main magnetic pole with a substantially arc shape corresponding to the shape.

[Embodiment 1] An embodiment of the present invention will be described below based on FIGS. 1 to 14.

As shown in Fig. 2, the optically assisted magnetic recording/reproducing device is
Recording, reproduction, or erasing is performed on a disk 8 including a substrate 5, a recording film 6 as a recording medium formed on the substrate 5, and a protective film 7 for protecting the recording film 6. It is equipped with an optical head that irradiates the recording film 6 with a laser beam 10 through the recording film 6, and a floating magnetic helad 11. The floating magnetic head 11 has a suspension 12 made of a leaf spring or the like.
As the disk 8 rotates, the disk 8
It is designed to float above the surface.

As shown in FIG. 3, groups 2, 2, and lands 3, 3, and so on are alternately formed on the substrate 5 with a predetermined pinch, and the groups 2, 2, and lands 3, 3, and so on are alternately formed along each land 3 in an approximately arcuate or crescent shape. Recording pits 1 . . . (see FIG. 4) are formed to form magnetic domains in the shape of a shape, and information is recorded.

As shown in FIG. 5, the floating magnetic head 11 has a magnetic head main body 14 mounted on a slider 13 that can slide on the disk 8.
The magnetic head main body 14 includes a reproducing head section 16 around which a reproducing coil 15 is wound, and a recording coil 1.
7 is wound around the return path section 18.

As shown in FIGS. 1(a) and 1(b), the magnetic head body 1
4 is made of MnZn ferrite or the like and includes a magnetic core 20 constituting the return bus section 18 .

The magnetic core 20 includes a reproduction coil 15 and a recording coil 1.
A coil winding groove 2121 for winding the coil 7 is formed. A non-magnetic material 22 serving as a base material is adhered to the magnetic core 20 on the outside of one coil winding groove 21, and a non-magnetic material 23 is adhered to the magnetic core 20 on the outside of the other coil winding groove 21. is glued. In addition, coil winding grooves 21, 21
A recording magnetic pole part 24 made of a magnetic material is attached to the magnetic core 20 in between.
is glued.

In the above reproducing head section 16, the non-magnetic material 22 as a base material and the outer surface of the magnetic core 20 are
As shown in the figure, a convex portion 25 (curved portion) curved in an arc shape is formed. A main magnetic pole 26 made of a thin film is formed on the convex portion 25, and a protective layer 27 is formed on the main magnetic pole 26. As shown in FIG. 5, the reproducing coil 15 is wound around the main magnetic pole 26 on the protective layer 27, while the recording coil 17 is wound around the recording magnetic pole part 24. .

In the above configuration, as the disk 8 rotates during recording or reproduction, the slider 13 rises above the surface of the disk 8, as shown in FIG. When recording, in this state,
By applying a magnetic field generated by the recording coil 16 wound around the recording magnetic pole part 23 to the recording film 6 while irradiating the recording film 6 with the laser beam 10 from the optical head, the recording film 6 is formed into a substantially arcuate shape with high recording density. A recording layer 1 . . . is formed on the recording film 6 .

On the other hand, during reproduction, the magnetic flux from each recording bit 1 on the recording film 6 is guided to the main magnetic pole 26. At this time, when the magnitude of the magnetic flux passing through the main magnetic pole 26 changes, a voltage is induced in the reproducing coil 15 accordingly, so by detecting the voltage of the reproducing coil 15, Information is detected.

Next, a method of manufacturing the floating type magnetic-soto type 1 will be explained.

When manufacturing the magnetic head main body 14, first, as shown in FIG. 6, a magnetic core 2 made of MnZn ferrite, etc.
0 is prepared, non-magnetic materials 22 and 23 are attached to both ends of the front surface of the magnetic core 20, and glass or glass thin films are used as adhesives.
Adhesion is achieved by melting at a temperature of about 0'C.

Similarly, a recording magnetic pole part 24 made of a magnetic material is adhered to approximately the center of the front surface of the magnetic core 20.

Next, as shown in FIG. 7, coil winding grooves 21 are formed between the nonmagnetic material 22 and the recording magnetic pole section 24 and between the nonmagnetic material 23 and the recording magnetic pole section 24.

Subsequently, as shown in FIG. 8, a photoresist film 28 is formed on the outer surfaces of the nonmagnetic material 22 and the magnetic core 20 so as to have a substantially arc shape. Then, when the non-magnetic material 22 and the magnetic core 2 (H-etching) are performed by ion milling using Ar gas, etc., approximately arc-shaped convexities are formed on the outer surfaces of the non-magnetic material 22 and the magnetic core 20, as shown in FIG. A convex portion 25 is formed.Instead of the convex portion 25, a roughly arcuate concave portion may be formed.Also, in the above, the convex portion 25 is formed along the entire length of the non-magnetic material 22 and the magnetic core 20. Although the non-magnetic material 22 is provided across the entire length, the substantially arc-shaped protrusion may be provided only on the front end of the non-magnetic material 22 facing the disc 8.

Next, as shown in FIGS. 10(a) and 10(b), the convex portion 25
The main magnetic pole 26 is formed by depositing FeSi, CoNbZr, NiFe, etc. on the top by sputtering or the like to a thickness of about 0.1 to 0.2 μm. On the non-magnetic material 22, the main magnetic pole 26 is formed only on the convex portion 25, and on the magnetic core 20, it is formed in an area wider than the convex portion 25, including the convex portion 25.

Next, as shown in FIG.
enhanced Chemical Vapor Dep
The protective layer 27 is formed by depositing a thickness of several gm by a method such as a photocoating method.

Note that, for convenience of explanation, the steps up to the formation of the main magnetic pole 26 and the protective layer 27 have been described above as being performed independently for each magnetic head body 14, but in FIG. The magnetic core 20 is formed by using long pieces in the left-right direction and in the direction perpendicular to the plane of the paper, and by using pieces long in the direction perpendicular to the plane of the paper as the non-magnetic materials 22 and 23 and the recording magnetic pole part 24. By providing a plurality of similar structures in the left and right direction, a plurality of main magnetic poles 26 are arranged two-dimensionally, and after the process of forming the protective layer 27 is completed, they are separated into individual magnetic head bodies 14. You can do it like this.

Next, the manufacturing process of the slider 13 will be explained.

First, for the slider material 41 as shown in FIG.
A head insertion groove 42 is formed (FIG. 12). Next, rail forming grooves 43 are formed on both sides of the head insertion groove 42, and a suspension mounting groove 44 is formed on the back side of the slider material 41 in a direction perpendicular to the rail forming grooves 43. Figure 13).

Once the magnetic head body 14 and slider 13 are configured,
As shown in FIG. 14, the head insertion groove 4 of the slider 13
The magnetic head main body 14 is inserted into the
It is bonded with glass or the like melted at a temperature of about 100 ℃.

Next, as shown in FIG. 5, the rail surface 45 of the slider 13 is
45 . . . and the surfaces of the non-magnetic materials 22 and 23 and the recording magnetic pole portion 24 that are continuous with the central rail surface 45 are ground and polished. Inclined surfaces 46, 46, . . . for introducing air between the disk 8 and the slider 13 are formed near the opposite end. Further, the recording coil 17 is wound around the recording magnetic pole section 24, and the reproducing coil 15 is wound around the main magnetic pole 26 of the reproducing head section 16.

In the above embodiment, the slider 13 and the magnetic head body 14 are constructed separately, but the slider 13 and the magnetic core 20 of the magnetic head body 14 may be constructed integrally.

[Example 2] Next, a second embodiment will be explained.

In this embodiment, the wire-wound regeneration coil 1 of the first embodiment is
5, a reproducing coil 51 made of a thin film is used as shown in FIG. 15(a).

That is, on the outer surfaces of the nonmagnetic material 22 and the magnetic core 20, there are rear thin film coils 54 and 55 insulated from the main magnetic pole 53 by the insulating layer 52, and w! ! , the main magnetic pole 5 by the edge layer 56
Front side thin film coils 58 and 60 are insulated from the main magnetic pole 53 and covered with a protective layer 57. They are connected to form a reproduction coil 51. Note that parts having the same configuration as those in the first embodiment are given the same reference numerals and redundant explanations will be omitted.

The manufacturing procedure of the magnetic head main body 50 of this embodiment will be described below.

The procedure for forming the convex portions 25 on the outer surfaces of the magnetic core 20 and the non-magnetic material 22 is the same as in the first embodiment (see FIGS. 6 to 9).

After forming the convex portion 25, as shown in FIGS.
Form 4.55. The back side thin film coil 54 extends along the nonmagnetic material 22 and an example of the magnetic core 20 to near the rear end of the magnetic core 20 . In addition, the back side thin film coil 54.
55 is Nb (0.05um), Cu (1μm)
, Nb (0,1 μm) and Ti (0,2 μm)
EB (Electron Beam)
After vapor deposition, unnecessary portions are removed by etching such as ion milling.

Subsequently, as shown in FIG. 17, the back side thin film coil 54 is
- After forming the insulating layer 52 by depositing SiO□ on the layer 55 by P-CVD or the like, or by applying an appropriate material by a spin code method or the like and baking it (for example, at about 300°C), Remove unnecessary parts by reactive ion etching etc.

Next, as shown in FIGS. 18(a) and (b), FeSi
, CoNbZr, NiFe, etc., for example, 0.1~0°2μ
The main magnetic pole 26 is formed along the convex portion 25 by sputtering about m and removing unnecessary portions by ion milling or the like.

Next, 1 layer of SiO□ was deposited on the main pole 26 using the P-CVD method.
The insulating layer 56 is formed by depositing about μm (
(Fig. 19), then Nb (0.05 μm
), Cu (1 μm), Nb (0.1 μm), and Ti (0.2 μm) are sequentially deposited by EB evaporation, and unnecessary portions are removed by ion milling or the like to form the front side thin film coils 58 and 60. (Figure 20(a)(b)
). Both ends of the front side thin film coil 58 are connected to each end of the back side thin film coils 54 and 55, and one end of the front side thin film coil 60 is connected to the other end of the back side thin film coil 55. 60 is the back side thin film coil 54
It also extends to the vicinity of the rear end of the magnetic core 20. Note that before forming the front side thin film coils 58 and 60, the insulating layer 52 is
・Remove the connecting portion between the back side thin film coils 54 and 55 and the front side thin film coils 58 and 60 at 56.

Next, a protective layer 57 is formed by depositing S+Oz on the front side thin film coils 58 and 60 by the P-CVD method (FIGS. 15(a) and 15(b)). Note that the area 6 shown by hatching in FIG. 20(a) in this protective layer 57
1.62, that is, the regions corresponding to the external connection ends of the back side thin film coil 54 and the front side thin film coil 60 are removed by etching.

Thereafter, this magnetic head main body 50 is connected to the slider 13, and after necessary grinding, polishing, etc. are performed, the recording coil 17 is wound around the recording magnetic pole part 24.

Note that in this embodiment as well as in the first embodiment, the magnetic core 2
0. By using long pieces of non-magnetic material 22 and 23 and the recording magnetic pole part 24, it is possible to manufacture the upper body 50 at the same time and then separate it, or The core 20 and the slider 13 can be constructed integrally.

[Effects of the Invention] As described above, the magnetic head according to the present invention includes a thin film core formed on a base material, and has a main body having a substantially arcuate shape that is substantially the same as the shape of the magnetic domain when viewed from the recording medium side. magnetic pole and
This configuration includes a reproducing coil provided around the main magnetic pole and a recording coil provided in a return bus section for magnetic flux from the main magnetic pole.

In this way, since the main magnetic pole has a substantially circular arc shape corresponding to the shape of the magnetic domain on the recording medium, crosstalk does not occur between a plurality of adjacent magnetic sections on the recording medium, and
It becomes possible to obtain sufficient reproduction signal output. As a result, in optically assisted magnetic recording, accurate reproduction can be performed even when recording bits are formed into a substantially circular arc shape to increase recording density.

On the other hand, in the method for manufacturing a magnetic head according to the present invention, a curved portion (concave or convex portion) having a substantially arc shape is formed on the base material by etching, and then a main magnetic pole made of a thin film core is formed on the base material. In addition, the main magnetic pole is provided with a reproducing coil and a recording coil is provided in the return bus section.

As a result, first, a curved portion having a shape corresponding to the magnetic domain on the recording medium having a semicircular arc shape is formed on the base material, and then the main magnetic pole is formed by a thin film on the base material.
This has the effect that a substantially arc-shaped main magnetic pole corresponding to the shape of the magnetic domain on the recording medium can be formed.

[Brief explanation of drawings]

1 to 14 show an embodiment of the present invention. FIG. 1(a) is a schematic vertical sectional view of the magnetic head main body. Figure (b) is a schematic bottom view of the same. FIG. 2 is a schematic diagram of a magneto-optical recording/reproducing apparatus equipped with a floating magnetic head. FIG. 3 is a schematic longitudinal sectional view of the disk. The fourth is an explanatory diagram showing the shape of recording bits. FIG. 5 is a perspective view of the floating magnetic head. FIG. 6 is a schematic front view showing how a nonmagnetic material and a recording magnetic pole part are adhered to a magnetic core. FIG. 7 is a schematic front view showing how the coil winding grooves are formed in the magnetic core. FIG. 8 is a schematic bottom view showing how a photoresist film is formed. FIG. 9 is a schematic bottom view showing how etching is performed through a photoresist film. FIG. 10(a) is a schematic plan view showing how the main magnetic pole is formed. Figure (b) is a schematic sectional view taken along line A--A in figure (a). FIGS. 11 to 13 are schematic perspective views showing the manufacturing steps of the slider, respectively. FIG. 14 is a perspective view showing how the magnetic head body is bonded to the slider. FIGS. 15 to 20 show other embodiments of the present invention. FIG. 15(a) is a schematic vertical sectional view of the magnetic head main body. Figure (b) is a schematic bottom view of the same. FIG. 16(a) is a schematic front view showing how the back side thin film coil is formed. Figure (b) is a schematic sectional view taken along line BB in figure (a). FIG. 17 is a schematic vertical cross-sectional view showing how an insulating layer is formed. FIG. 18(a) is a schematic plan view showing how the main magnetic pole is formed. FIG. 0)) is a schematic sectional view taken along line CC in FIG. 0(a). FIG. 19 is a schematic vertical cross-sectional view showing how an insulating layer is formed. FIG. 20(a) is a schematic plan view showing how the front side thin film coil is formed. The figure (b) is a schematic sectional view along the DD line of the figure (a). 6 is a recording film (recording medium), 15 and 51 are reproduction coils,
17 is a recording coil, 18 is a return bus portion, 22 is a non-magnetic material (substrate), 25 is a convex portion (curved portion), and 26 and 53 are main magnetic poles. Figure 1 (a) Figure 1 (b) Patent applicant Sharp Corporation Figure 10 (a) Figure 10 (b) Figures Figure 15 (a) Figure 15 (b) Figure 16 (a) Figure 16 (b) Figure 17 n j Figure (a) Figure 18 (b) Figure 19

Claims (1)

[Scope of Claims] 1. A magnetic head used for recording and reproducing information recorded in substantially arc-shaped magnetic domains on a recording medium by optically assisted magnetic recording, which comprises a thin film formed on a base material. a main magnetic pole consisting of a core and having a substantially circular arc shape that is substantially the same as the shape of the magnetic domain when viewed from the recording medium side; and a reproducing coil provided around the main magnetic pole;
A magnetic head comprising a recording coil provided in a return path of magnetic flux from a main magnetic pole. 2. A step of forming a curved portion having an approximately arc shape on the base material by etching, a step of forming the main magnetic pole made of a thin film core on the base material on which the curved portion is formed, and a step of regenerating the main magnetic pole. 2. A method of manufacturing a recording magnetic head according to claim 1, further comprising the step of providing a recording coil in a return path section and a recording coil in a return path section.