JP2779526B2 - Composite thin film magnetic head - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to a thin film magnetic head used for a magnetic recording device, a VTR, and the like, and particularly to a recording head and a reproducing head suitable for ultra-high density magnetic recording and reproduction. The present invention relates to an integrally formed composite thin film magnetic head and a magnetic recording device.

[Conventional technology]

One method of combining a conventional inductive thin film magnetic head with a magnetoresistive thin film magnetic head is disclosed in Japanese Patent Application Laid-Open No. 58-189818.
As described in Japanese Patent Application Laid-Open Publication No. H10-157, a method of forming a magnetoresistive thin-film magnetic head on an upper surface of an upper magnetic film via an electrical insulating film has been proposed, and a method of reducing a gap at an end portion of the upper magnetic film has also been proposed. Proposed.

A method of forming a magnetic film by dividing the magnetic film into a front portion and a rear portion is proposed in Japanese Patent Application Laid-Open No. 60-10410 (US priority). According to this method, it is possible to form a thin film magnetic head having excellent recording characteristics because the front end of the magnetic film can be formed of a high saturation magnetization alloy and the rear can be formed of a material having high magnetic permeability. I have.

Further, Japanese Patent Application Laid-Open No. 60-10409 proposes a method in which only the top portion of the upper magnetic film is formed before forming the insulating film, and then the insulating film and the rear portion of the upper magnetic film are formed. By using this method, the width of the upper magnetic film can be determined with almost no step, so that the dimensional accuracy in the track width direction is improved.

And, JP-A-62-71006 and JP-A-63-16881
In Japanese Patent Application Publication No. 2000-135, a method is proposed in which after forming the lowermost insulating film, only the tip portion of the upper magnetic film is formed, and then the upper layer portion of the insulating film and the rear portion of the upper magnetic film are formed. By using this method, the width of the upper magnetic film is determined in a state where the step is low, so that the dimensional accuracy in the track width direction is improved.

Next, in JP-A-58-19718, a through hole is provided in a magnetoresistive film via an insulating film, and a conductor is connected to the magnetoresistive film there, and used as a magnetic head for magnetic recording. It is described that a large output was obtained upon reproduction.

[Problems to be solved by the invention]

The above prior art is disclosed in JP-A-60-10409,
-10410 JP, JP-A-62-71006, JP-A-63-16
JP-A-8811 proposes a method of forming an upper magnetic film of an inductive thin film magnetic head by dividing the upper magnetic film into a tip portion and a rear portion. The thin film magnetic head for inductive recording and the thin film magnetic for magnetoresistive effect reproduction are proposed. No suggestion is made regarding the method of combining with the head.

Japanese Patent Application Laid-Open No. 58-189818 proposes a method of combining a thin-film magnetic head for inductive recording and a thin-film magnetic head for magnetoresistive effect reproduction. No suggestion is made regarding head alignment. When there is a positional deviation (off-track) between the recording magnetic head and the reproducing magnetic head in the track width direction, when reproducing the stored magnetic information, the reproducing magnetic head is displaced from the position where the magnetic information is present on the track. Therefore, the reproduction output is reduced, and crosstalk occurs in which the magnetic information of the adjacent track is mixed. For the relationship between the displacement and the decrease in the reproduction output, see IEE Transactions on Magnetics 25 (1).
(1989) pages 710 to 715 (IEEE, Trans. Magnetics)
25 (1) 1989 pp. 710 to 715), and alignment is an important technical problem for a composite thin film magnetic head.

Furthermore, when a through-hole is provided in an insulating film covering the magnetoresistive effect film to connect the magnetoresistive effect film and the conductor, a method of processing the track width accurately without damaging the magnetoresistive effect film, that is, a magnetoresistive effect. Japanese Patent Application Laid-Open No. 58-19718 does not suggest any method for processing a through hole while maintaining the end face shape of the film accurately.

Track width dimension error is ± 10% of track width
If the track width is 5 μm, the value is ± 0.5 μm or less. If you try to reduce the dimensional error of the track width in the process of forming through holes,
The magnetoresistive film is damaged. The processing method for forming through holes is usually a wet etching method or an ion milling method. In the wet etching method, the damage of the magnetoresistive film is small, but the track width dimension error of ± 0.5 μm is limited to the above magnetoresistive effect. This is difficult because the end face of the film is slightly over-etched. In the ion milling method, although the track width dimension error is small, there is a problem that the magneto-resistive film is damaged by the over milling.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a thin-film magnetic head for performing ultra-high-density recording by preventing misalignment between an inductive recording head and a magnetoresistive reproducing head in a composite thin-film magnetic head and a magnetic recording apparatus using the same. Is to do.

[Means for solving the problem]

The object is to form a lower magnetic film in a concave shape, dispose a conductor coil and an insulating material covering the conductor coil in the concave portion, form the insulating material surface flat, and form the insulating material surface and the lower portion. A first gap material is formed on the surface of the magnetic film on the magnetic recording surface side, and the first magnetic material and an upper magnetic film including a front end and a rear portion are substantially formed on the surface of the lower magnetic film opposite to the magnetic recording surface. A recording thin-film magnetic head formed flat to record an electric signal as magnetic information; and a second gap material formed on a front end surface of the upper magnetic film, and a magnetoresistive effect film formed on the second gap material surface. And a reproducing thin-film magnetic head for reproducing magnetic information by forming a tip of the upper magnetic film, a shape of the second gap material, and a shape of the magnetoresistive film in a track width direction and a direction of the upper magnetic film. Composite thin-film magnetic head identical in rear direction It is achieved by providing.

The above object is achieved by providing a magnetic recording apparatus using the composite thin-film magnetic head described above.

[Action]

According to the above configuration, the lower magnetic film is formed in a concave shape with a depth of 5 to 10 μm, and the conductor coil and the insulating material covering the conductor coil are disposed therein, and the upper magnetic film is flattened thereon. After that, a gap material and a magnetoresistive effect film are sequentially formed on the upper magnetic film surface, so that there is no displacement between the respective films in the track width direction, and a displacement from a position where magnetic information exists on the track. Thus, it is possible to prevent a decrease in reproduction output due to tracing, and a crosstalk in which magnetic information of an adjacent track is mixed.

When a conductor is connected to the magnetoresistive film, the portion between the conductors operates as a magnetoresistive film, so that the upper magnetic film and the magnetoresistive film are formed to have the same width in the track width direction. The magnetic head for reproduction using a magnetoresistive film becomes smaller by the size of the conductors at both ends, and can be written on a track and reproduced from a narrow part. Even if the mechanism is displaced, it is possible to prevent the recording magnetic head from deviating from the written portion.

When a conductor is connected by providing a through hole in the insulating material that covers the magnetoresistive element, the shape of the through hole is formed using a photoresist as the insulating material and irradiated with light rays, for example, ultraviolet rays, and then developed and baked. However, since the magnetoresistive element is not damaged, the track width of the magnetoresistive element can surely maintain an accurate predetermined dimension.

〔Example〕

 An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a cross section of the composite thin film magnetic head used in the first embodiment in the track advancing direction. Alumina 20 is sputtered on the ceramic substrate 10 to a thickness of 7 to 8 μm, and a concave portion having a depth of 5 to 6 μm is formed by an ion milling method. A lower magnetic film 30 is sputtered thereon as a lower magnetic core by about 2 μm and patterned into a magnetic core shape. In the concave portion of the lower magnetic film 30, a coil 50 and an insulating material 40 covering the coil 50 with a copper conductor are provided with a photoresist here,
0.4 μm of alumina is sputtered as a gap material 60 on the insulating material 40 and the lower magnetic film 30 on the writing surface side, and an upper magnetic film 65 is sputtered thereon by about 2 μm and then flattened. As alumina on it
0.1-0.2μm sputtered and magnetoresistive film
Sputter 100. If the depth of the concave portion of the alumina 20 is less than 5 to 6 μm, the coil 50 and the insulating material 40 covering the coil 50 cannot be provided, and making the coil deeper makes the processing difficult. Next, in the direction parallel to the track width, the magnetoresistive film 10
0 and the gap material 90 are patterned. Thereafter, the magnetoresistive film 100, the gap material 90 and the upper magnetic film 65 are simultaneously patterned. Also, the magnetoresistance effect film 10 of the upper magnetic film 65
If the unevenness on the 0-side surface is not reduced to 1 μm or less, the magnetoresistive film 1
It becomes difficult to form 00, and its characteristics also deteriorate. A photoresist is applied as a through-hole insulating material 110 on the magnetoresistive film 100 and optically processed to form a through-hole. Conductor 1 in through-hole part of magnetoresistive film 100
20 Here, Cr / Cu is subjected to sputtering and patterning of about 0.03 to 0.5 μm, and a reproduction output is taken out by the conductor 120. Then, 0.1 to 0.2 alumina is used as the gap material 130.
The magnetic shield material 140 is sputtered about 2 μm thereon and patterned. Finally, alumina is sputtered as a protective film 150 by 10 to 30 μm to complete the formation of the composite thin-film magnetic head.

FIG. 2 shows a cross section of the composite thin film magnetic head used in the second embodiment in the track advancing direction. Alumina 20 is sputtered on the ceramic substrate 10 to a thickness of 7 to 8 μm, and a concave portion having a depth of 5 to 6 μm is formed by an ion milling method. A lower magnetic film 30 is sputtered thereon as a lower magnetic core by about 2 μm and patterned into a magnetic core shape. In the concave portion of the lower magnetic film 30, a coil 50 and an insulating material 40 covering the coil 50 with a copper conductor are provided with a photoresist here,
0.4 μm of alumina is sputtered as a gap material 60 on the insulating material 40 and the lower magnetic film 30 on the writing surface side, and a magnetic film 70 is sputtered thereon for about 2 μm for the rear of the upper magnetic film. Is patterned.
Then, the upper magnetic film 80 is used for the top of the upper magnetic film.
Sputtering is performed with the end face in close contact with 70. Further, alumina is sputtered thereon as a gap material 90 by 0.1 to 0.2 μm, and a magnetoresistive film 100 is sputtered and patterned into a magnetoresistive head shape. At this time, when the magnetic film 70 is patterned at an angle of 45 ° to 70 ° with respect to the gap material 60, the bulge of the upper magnetic film 80 becomes gentle at the boundary surface between the upper magnetic film 80 and the magnetic film 70, and The gap material 90 to be sputtered thereon adheres well. Next, a photoresist is applied as a through-hole insulating material 110 on the magnetoresistive film 100, and optical processing is performed to form a through-hole. Conductor 120 in the through-hole portion of the magnetoresistive film 100, where Cr / Cu is about 0.03-0.5
μm sputtering and patterning the conductor 120
To retrieve the playback output. Then, a gap material 130 is sputtered with 0.1 to 0.2 μm of alumina, and a magnetic shield material 140 is sputtered thereon for about 2 μm and patterned. Finally, alumina is used as the protective film 150 for 10-30.
The formation of the composite thin-film magnetic head is completed by the μm sputtering.

FIG. 3 shows a cross section of the composite thin film magnetic head viewed from the air bearing surface side, that is, from the magnetic recording surface side. Assuming that the horizontal direction in FIG. 3 is the track width direction, the lower magnetic film 30 has the largest track width, the upper magnetic film 80 has the next largest track width, and the track width of the magnetoresistive film 100 is effectively effected by the interval between the conductors 120. So its width is the smallest. The track width of the inductive thin-film magnetic head for recording is dominated by the smaller upper magnetic film 80, but it is larger than the magneto-resistive film 100 of the magneto-resistive magnetic head for reproduction and is widely written on the magnetic recording surface. Since the information is reproduced narrowly, magnetic information can be surely reproduced. Further, since the lower magnetic film 30, the upper magnetic film 80, and the magnetoresistive film 100 are sequentially formed on the same substrate by repeating sputtering and patterning, there is no displacement between the recording magnetic head and the reproducing magnetic head.

An embodiment of a magnetic recording apparatus using the composite thin film magnetic head of the present invention will be described.

FIG. 4 shows the configuration of the magnetic recording apparatus. A motor 203 supported by a base 201 drives a spindle 202 to rotate a plurality of disk-shaped magnetic disks 204 attached to the spindle 202. The control current from the voice coil motor control circuit is output to the voice coil 207 provided in the magnet 208, and the voice coil motor drives the voice coil 207 by the action of the magnetic field and the control current by the magnet 208. The voice coil 207 drives and couples the carriage 206 and the magnetic head 205 for positioning and the magnetic head 205 for positioning.
Determine the position of a. The data magnetic head 205 is connected to a write / read circuit and connected to a host device such as a computer system via an interface.
Exchange information with 4 Magnetic head for positioning 2
05a is connected to the voice coil motor control circuit, detects and provides a position on the magnetic disk 204, and uses it for position control.

FIG. 5 is an enlarged view of a part of the data magnetic head 205 that floats by a dimension t due to the effect of an air current generated by the rotation of the magnetic disk 204 called a slider 211 in the rotation direction 212 and the magnetic disk 204. Magnetic disk 204 therein to form a magnetic layer 204b on one or both sides of a non-magnetic disc 204a such as alumina, a large number of the track grooves of the track pitch T _P at a recording wavelength 209 is provided. As a high-performance magnetic recording device, the areal recording density of the magnetic disk 204 is 7 per square centimeter.
It is preferable that the linear recording density is not less than 4.7 kilobits per centimeter and the track density is not less than 230 tracks per centimeter.With such performance, recording can be performed without significantly increasing the diameter of the magnetic disk 204. Density can be increased. As described above, by using the composite thin film magnetic head of this embodiment,
It is possible to provide a magnetic recording device, such as a hard disk device, a floppy disk drive device, and a video tape recorder, which can achieve a high recording density of 7 megabits per square centimeter or more per square centimeter and have excellent characteristics for reliably reproducing magnetic information.

〔The invention's effect〕

According to the present invention, the inductive thin film magnetic head for recording of the composite thin film magnetic head and the magnetoresistive effect type magnetic head for reproducing are formed as a thin film on the same substrate in order to eliminate the displacement, The effect of preventing a decrease in reproduction output and crosstalk from an adjacent track and enabling high-density recording is obtained.

In addition, if a photoresist is used as an insulating material for covering the magnetoresistive film of the magnetoresistive head, when a through hole for connecting a conductor to the magnetoresistive film is provided, the magnetoresistive film can be formed without being damaged. Accurate track width is obtained.

Further, by using a composite thin film magnetic head having no displacement between the recording magnetic head and the reproducing magnetic head of the present invention, a magnetic recording having a large recording density and an excellent characteristic of reliably reproducing recorded magnetic information. A device can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a composite thin-film magnetic head according to a first embodiment of the present invention viewed from the track traveling direction. FIG. 2 is a view of the composite thin-film magnetic head according to the second embodiment of the present invention viewed from the track traveling direction. FIG. 3 is a sectional view of the composite thin-film magnetic head according to the second embodiment of the present invention as viewed from the magnetic recording surface side, and FIG. 4 is a perspective view showing the configuration of a magnetic recording apparatus to which the present invention is applied. FIG. 5 is a perspective view showing an enlarged magnetic head and a magnetic disk of the magnetic recording apparatus shown in FIG. 10 ceramic substrate, 20 alumina, 30 lower magnetic film, 40 insulating material, 50 coil, 60 gap material, 65 upper magnetic film, 70 magnetic film, 80 …… Upper magnetic film, 90 …… Gap material, 100 …… Magnetoresistance effect film, 110 …… Insulation material for through hole, 120 …… Conductor, 130 …… Gap material, 140 …… Magnetic shield material, 150 …… Protective film, 204: Magnetic disk, 211: Slider

Continuing on the front page (72) Inventor Hiroshi Fukui 4026 Kuji-cho, Hitachi City, Ibaraki Prefecture Inside Hitachi, Ltd.Hitachi Research Laboratory, Ltd. 72) Inventor Shinji Narushige 4026 Kuji-cho, Hitachi City, Ibaraki Prefecture Within Hitachi Research Laboratory, Hitachi, Ltd. (56) References JP-A-1-96814 (JP, A) (58) Fields investigated (Int. Cl. ⁶⁾ , DB name) G11B 5/39

Claims (6)

(57) [Claims] A lower magnetic film formed in a concave shape, a conductor coil and an insulating material covering the conductor coil are disposed in the concave portion, and the insulating material surface is formed flat; Forming a first gap material on the magnetic recording surface side surface of the lower magnetic film;
A thin film magnetic head for recording for recording an electric signal as magnetic information by forming an upper magnetic film having a front end and a rear substantially flat on the surface of the first gap material and the surface of the lower magnetic film opposite to the magnetic recording surface. And a second surface on the tip surface of the upper magnetic film.
A reproducing thin-film magnetic head for reproducing magnetic information by forming a magnetoresistive film on the surface of the second gap material, wherein a tip of the upper magnetic film and the second magnetic material are formed.
Wherein the shape of the gap material and the shape of the magnetoresistive film are the same in the track width direction and the rear direction of the upper magnetic film. 2. The composite thin-film magnetic head according to claim 1, wherein the unevenness on the surface of the upper magnetic film on the side of the second gap material is 1 μm or less. 3. The distance between the upper magnetic film and the lower magnetic film is five.
3. The composite thin-film magnetic head according to claim 1, wherein the thickness is at least μm. 4. The electrical insulating material covering the magnetoresistive film is provided with through holes to connect conductors, and a photoresist is used as the electrical insulating material. 3. The composite thin-film magnetic head according to item 1. 5. The magnetic recording surface according to claim 1, wherein a rear side of the upper magnetic film has an angle of 45 ° to 75 ° with respect to the second gap material. A composite thin-film magnetic head according to claim 1. 6. A magnetic recording apparatus using the composite thin-film magnetic head according to claim 1.