JPS60115014A - Magnetic head for vertical magnetization - Google Patents

Abstract

PURPOSE:To attain both recording and reproducing functions by filling a nonmagnetic insulated material into a cut groove formed at a part of a magnetic substrate to form a coil layer on said insulated material and then forming an MR element via an insulated layer to provide the 1st and 2nd magnetic thin films on the MR element. CONSTITUTION:A coil layer 12 is formed on a single side of a magnetic substrate 10 where a nonmagnetic insulated material 11 is filled. An MR element film 14 is formed via an insulated layer 13, and conductor layers are provided at both ends of the MR element 14 for supply of current. Then the 1st magnetic thin film 16 having an end exposed, an insulated layer 17 and the 2nd magnetic thin film 18 are formed on the driving surface of a recording medium 4. The reluctance force of the film 18 is set larger than that of the film 16. The magnetic fluxes flow through the 1st and 2nd magnetic films in a record mode when a record current is flowed to a coil layer 12. These magnetic fluxes are concentrated to the tip of the film 18. Thus the vertical recording is possible. While the signal magnetic flux detected by the film 16 does not leak out so much to the film 18 in a reproeuction mode.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to vertical magnetic recording devices used in perpendicular magnetic recording type magnetic recording devices, such as computer disks, tape devices, floppy disk devices, digital PCM recorders, digital VTRs, etc. This invention relates to a magnetic head for magnetization.

Conventional Structure and Problems Conventionally, as shown in FIG. 1, perpendicular recording was performed on a recording medium 4 having a high magnetic permeability layer 2 such as permalloy and a Co--Cr vertically deposited layer 3 on a base film 1. As a magnetic head for reading signals, a perpendicular magnetization head using a magnetoresistive element (hereinafter simply referred to as an MR element) 6 has been proposed. This type of head has a notch in a part of the magnetic substrate 6, and the groove is filled with a non-magnetic insulator.
Moreover, it is a formed structure. A kind of closed magnetic circuit is constituted in which the signal magnetic flux passes through the magnetic flux guide section 8, the MR element 5, and the magnetic flux return section 9 and returns to the high magnetic flux layer 2 of the recording medium 4.
This head is capable of efficiently reproducing signals. However, such a head basically does not have a recording function, and a recording head must be provided separately. If recording and playback are separated in this way, it becomes one of the obstacles to miniaturization of the device itself, and it is a problem in terms of realizing inexpensive devices. However, there was a need for a recording/reproducing magnetic head with an efficient recording function.

OBJECTS OF THE INVENTION An object of the present invention is to provide a novel perpendicular magnetization magnetic head having highly efficient recording and reproducing functions.

Structure of the Invention In the present invention, a cutout groove filled with a non-magnetic insulating material is arranged in a part of a magnetic substrate, and a coil layer with a predetermined number of turns is formed on a surface different from the recording medium running surface. Next, an MR element is placed at a position separated from the recording medium running surface via an insulating layer, and one end of the MR element is magnetically coupled to the magnetic substrate. Terminal layers to which current is supplied are formed at both ends of the MR element, and means for supplying current is added. At the top is the first. Second
A magnetic thin film is formed. One end of the first magnetic thin film is exposed to the recording medium running surface, and the other end is magnetically coupled to the MR element and serves as a magnetic flux guiding section. The second magnetic thin film has one end that is magnetically coupled or physically continuous with the first magnetic thin film, and the other end that faces the magnetic flux return portion of the magnetic substrate and is magnetically coupled to the first magnetic thin film or is physically continuous with the first magnetic thin film. The magnetic yoke is combined with the magnetic yoke. Second
The coercive force of the first magnetic thin film is made to be stronger than that of the first magnetic thin film.

DESCRIPTION OF THE EMBODIMENTS A first embodiment will be explained with reference to FIG. A groove is provided in a magnetic substrate 10 such as ferrite and filled with a non-magnetic insulating material 11 such as glass or barium titanate.
A coil layer 12 (FIG. 2 shows an example of 4 turns) is made of a conductive thin film such as L, Cu, or Au/Cr.

), then a non-magnetic insulating layer 13 such as S 102 +A22o3, and then a Fe-Ni film (in the figure, a current is passed in a direction perpendicular to the plane of the paper. The direction perpendicular to the plane of the paper is the track width direction) MR element 14 An, Cu, Au/
A conductor layer such as Cr is applied.

(Not shown.)? Ite, 5iO2Sio2. AL
The nonmagnetic insulating layer 16 203 is formed by vacuum evaporation or sputtering. Next, the first magnetic thin film 16 is formed so that one end thereof is exposed on the recording medium running surface, the non-magnetic insulating layer 17 provides some interlayer insulation, and the second magnetic thin film 18 is formed.

Note that the recording medium running surface herein refers to a surface that is used in contact with or in close proximity to the recording medium 4.

Sarani, s io2. Af), 203. A protective layer 19 such as Sio is laminated, and a protective plate 20 made of glass or the like or ferrite or the like is adhered to reduce external noise.

1st. The second magnetic thin film 16.18 is made of Fe-Ni.
Alloy film or Co-Nb-Zr system, C.

An amorphous film based on -Nb-Fe can be used. Manufacturing methods such as electron beam evaporation, plating, and snow ivy are selected depending on the material. First magnetic thin film 16
The thickness of the disc will become thinner as it becomes compatible with high-density recording. Usually about 0.1 to 1 μm is selected. Second magnetic thin film 1
8 is determined in consideration of the magnetic properties of the MR element 14, but for example, if the thickness and initial permeability of the MR element 14 are each 50.
Assuming 0 people and 2000 people, that of the second magnetic thin film is ~1
μm, 10 or less is selected. As a result, in terms of magnetoresistance, the branching of the magnetic flux to the second magnetic thin film 18 can be suppressed to about 10%, and the sensitivity does not need to drop much. It is preferable that the magnetic properties of the first magnetic thin film 16 be as soft as possible, and in that sense, the coercive force of the second magnetic thin film 18 is selected to be greater than that of the first. Generally, for the coercive force number Oe or less of the first magnetic thin film 16,
The coercive force of the second magnetic thin film 18 is from several 10 oe to several 1008 oe.
In the above configuration, during so-called recording when a recording current is passed through the coil layer, the magnetic flux level is extremely high. At that time, the magnetic flux flows through the second magnetic thin film and the first magnetic thin film, and the magnetic flux flows through the second magnetic thin film and the first magnetic thin film. Magnetic flux concentrates at the tip of the magnetic thin film, making perpendicular recording possible.On the other hand, during playback, the magnetic flux level is small, so the signal magnetic flux detected by the first magnetic thin film is transferred to the second magnetic thin film.
Since the liquid flows into the MR element without leaking into the magnetic thin film of the magnetic thin film, it is possible to maintain an efficient state.

Another embodiment is shown in FIG. This embodiment is almost the same as the embodiment shown in FIG. 2, and the same parts are given the same numbers and their explanations will be omitted. The difference is that by partially roughening the surface of the nonmagnetic insulating layer 15 formed on the MR element 14, the coercive force of the magnetic thin film formed thereon is partially increased. As a result, the first magnetic thin film part 21 (the surface roughness of this base surface is sufficiently small and the coercive force is also small in this upper part) and the second magnetic thin film part are physically continuous. 22. The relationship between surface roughness and coercive force changes depending on the thickness of the magnetic thin film, but
There is a correlation, and it is possible to obtain a predetermined coercive force by determining the surface roughness of the underlying surface.

Effects of the Invention As described above, according to the present invention, an MR element is laminated on a substrate at a position away from the recording medium running surface with a coil layer interposed therebetween, and furthermore, one end is placed on the recording medium running surface. A first magnetic thin film to be exposed and a second magnetic thin film magnetically coupled to the first magnetic thin film and surrounding the coil layer are provided, and the second magnetic thin film has a higher magnetic property than the first magnetic thin film. The coercive force is stronger than that of a thin film. As a result, a large level of magnetic flux can be passed through the first and second magnetic thin films during recording, and a reproduction magnetic flux can be efficiently passed from the first magnetic thin film to the MR transponder during reproduction, combining the functions of recording and reproduction. A small, highly efficient magnetic head for perpendicular magnetization can be realized.

[Brief explanation of the drawing]

Figure A 1 is a sectional view showing the vertical direction of the conventional example;
FIG. 2 is a sectional view showing a perpendicular magnetization magnetic head according to a first embodiment of the invention, and FIG. 3 is a sectional view showing another embodiment of the invention. 1o...Magnetic substrate, 11...Nonmagnetic insulating material, 12...Coil layer, 13,15.17...
...Nonmagnetic insulating layer, 14...MR element film,
16...First magnetic thin film, 18... Second magnetic thin film. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
figure

Claims (3)

[Claims] (1) A non-magnetic insulating layer is laminated on top of a coil layer formed on a substrate, and a magnetoresistive element is disposed above the coil layer and at a position away from the recording medium running surface, and the magnetoresistive effect a first magnetic thin film having one end exposed to the recording medium running surface on the upper part of the magnetoresistive element; and magnetically coupled to the first magnetic thin film; A magnetic head for perpendicular magnetization, characterized in that a second magnetic thin film is arranged to surround the coil layer, and the coercive force of the second magnetic thin film is stronger than the coercive force of the first magnetic thin film. (2) The substrate is a magnetic material, a groove is formed in a part of the non-magnetic material, and a coil layer is disposed on the non-magnetic material. Magnetic head for perpendicular magnetization. (3) First. The second magnetic thin film is a physically continuous integral film, and the surface roughness of the underlying surface on which the second magnetic thin film is formed is rougher than the surface roughness of the underlying surface of the first magnetic thin film. A magnetic head for perpendicular magnetization according to claim 1.