JPH0798681B2 - Flying magnetic head - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a levitation type magnetic head used in a magnetic disk device, and particularly to a composite type or quasi-monolithic type using a thin film laminated core as a head core. The present invention relates to a floating magnetic head.

2. Description of the Related Art Generally, a floating magnetic head used in a magnetic disk device includes a slider and a head core, and is connected to an actuator of a device body via a leaf spring support mechanism.

Conventionally, such a flying type magnetic head is (1) a monolithic type manufactured by forming a slider with ferrite, forming a gap in a part of the slider, and then cutting and grinding the slider into a predetermined shape, and (2) A slider is formed of a non-magnetic material such as ceramics, and there is a ferrite-type composite type manufactured by welding a head core made of ferrite to the slider with glass. In recent years, high density recording has been achieved. For this reason, Fe-Si has a high saturation magnetic flux density and excellent high frequency characteristics of magnetic permeability.
-A so-called MIG (Met (Met) that has magnetic thin films made of Al alloy etc.
MIG that uses an al In Gap) type head as the head core
Type composite type or pseudo-monolithic type floating magnetic heads have been attracting attention. Ferrite type and
As shown in FIG. 5, the MIG type composite type flying magnetic head incorporates a head core 1 into a predetermined groove-shaped recess 3 of a ceramic slider 2 formed by cutting and grinding a single ceramic, and a bonded glass. It is formed by welding with No. 4.

Furthermore, it is used for VTR, can achieve high-density recording, and can be narrowed track, thin film laminated core, that is, Fe-Si-Al.
A thin-film laminated composite type floating magnetic head using a thin-film laminated core formed by laminating a magnetic thin film made of an alloy (sendust), an amorphous magnetic material or the like on a non-magnetic substrate has been proposed. JP-A-62-18617 also proposes a thin-film laminated pseudo-monolithic type flying magnetic head using a thin-film laminated core as a head core.
An example is shown in Japanese Patent Publication No. 13.

For example, a thin-film laminated composite type flying magnetic head has a predetermined groove-shaped recess of a ceramic slider 2 formed by grinding a single ceramic as shown and described in the publication and FIG. 6 of the present application. It is manufactured by incorporating the head core 1 in the place 3 and welding it with the bonding glass 4.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention As materials for sliders, wear resistance, precision machinability, machining efficiency, high strength, fineness of structure, familiarity with recording medium, lubricity, and thermal compatibility with head core And various characteristics such as adhesion strength are required.

At present, CaTiO ₃ is generally used as a slider material, and a thin film head in which a so-called winding portion is also formed of a thin film has Al ₂ O ₃ -TiC as described in JP-A-55-163665.
The ceramic materials are considered to be one of the most suitable materials, but according to the results of the research and experiments conducted by the present inventors, the Al ₂ O ₃ -T
iC ceramic material or CaTiO ₃ is used as a head core.
It has been found that when a thin film laminated core made by laminating magnetic thin films made of Fe-Si-Al alloy or the like is used, there is a problem in terms of thermal compatibility with the head core and adhesion strength. .

In other words, Al ₂ O ₃ -TiC ceramic material and CaTiO ₃ ,
The difference in thermal expansion coefficient from the Fe-Si-Al alloy magnetic film is large, lacking thermal compatibility, and in the case of a composite type flying magnetic head, the head core is bonded to the slider due to thermal deformation. As a result, excessive stress is applied to the bonded glass layer, causing cracks in the bonded glass layer, and the adhesion strength of the head core to the slider and the CSS resistance are reduced.

In the process of researching and developing a flying magnetic head using a thin film laminated core having such a Fe--Si--Al alloy magnetic film as a head core, the inventors of the present invention used a slider of Co _X Ni
It has been found that the above problem can be solved by manufacturing with a ceramic material represented by _2-X O ₂ (however, 0.2 ≦ X ≦ 1.8).

The present invention has been made based on such novel findings.

Therefore, the object of the present invention is excellent in thermal matching and adherence strength with a head core having a Fe-Si-Al alloy magnetic film, wear resistance, precision workability, good CSS resistance. It is an object of the present invention to provide a flying type magnetic head capable of improving the above.

Means for Solving the Problems The above object is achieved by the flying magnetic head according to the present invention. In summary, the present invention relates to a flying magnetic head constructed by integrally providing a slider with a head core formed by laminating a magnetic thin film on a non-magnetic substrate, wherein the magnetic thin film of the head core is Fe--Si--Al. The flying magnetic head is an alloy magnetic film, and the slider is made of a ceramic material represented by Co _X Ni _2-X O ₂ (where 0.2 ≦ X ≦ 1.8). Preferably, the ceramic material for producing the slider has 0.1 to 5% by weight of at least one selected from MnO, TiO ₂ , Al ₂ O ₃ and CaO as a basic composition of CoO and NiO. Yes, one
5% by weight of Y ₂ O _3, 0.1~1 wt% of TiN and 0.3 to 2 of the weight% B ₂ O _3, it is also possible to add at least one. Furthermore, the slider is made of MgO, CaO, CoO and NiO.
A mixed ceramics of MgO and CaO
Each contain less than 30 mol% and the balance is Co _X Ni _2-X
It is also possible to make it with a ceramic material having a rock salt type structure with O ₂ (however, 0.2 ≦ X ≦ 1.8).

EXAMPLE Next, the floating magnetic head according to the present invention will be described in more detail with reference to the drawings.

Referring to FIG. 4, an embodiment of a composite type flying magnetic head constructed in accordance with the present invention is illustrated. In this embodiment, the floating magnetic head is provided with a slider 2 and a head core 1 as in the conventional case, and is connected to an actuator (not shown) of the magnetic disk device body via a leaf spring support mechanism 5.

Next, with reference to FIG. 3, an embodiment of a method of manufacturing a thin film laminated core, which is used as the head core 1 and is formed by laminating magnetic thin films on a non-magnetic substrate, will be described. An Fe-Si-Al alloy magnetic body is used as the magnetic thin film.

First, the non-magnetic substrate 11 is prepared (FIG. 3A), and the Fe-Si-Al alloy film 12 is formed on the substrate 11 by the sputtering method.
Is formed with a film thickness of 1 to 20 μm. Then, the Fe-Si-
A nonmagnetic insulating film 13 is formed on the Al alloy film 12 with a film thickness of 0.03 to 0.5 μm by a sputtering method (FIG. 3 (B)).
As the nonmagnetic insulating film 13, SiO ₂ , Al ₂ O ₃ or the like is used.

By repeating the above steps, the Fe-Si-Al alloy film 12 and the non-magnetic insulating film 13 are laminated a required number of times, and the alloy magnetic thin film 14 is formed on the substrate 11 as shown in FIG. It The outermost layer of the alloy magnetic thin film 14 is preferably the Fe-Si-Al alloy layer 12. At this time, the total thickness (t) of the alloy magnetic thin film 14 is
From an economical point of view, it is preferably 30 μm or less.

Then, the laminated glass 15 on the alloy magnetic thin film 14 has a film thickness of 0.05 to
It is formed by a sputtering method or the like at 0.5 μm (FIG. 3 (D)), and the other non-magnetic substrate 16 made of the same material as the previous substrate 11 is bonded onto the laminated glass 15 to make it magnetic. The core block 17 is produced (FIG. 3 (E)). Glass or SiO of _{SiO 2 -Al 2 O 3 -Na 2} O system a layered glass 15
_2- B ₂ O ₃ —Na ₂ O based glass is suitable.

The magnetic core block 17 manufactured in this way has a third
As shown in FIG. 4F, the laminated half-blocks 18 and 19 are formed by cutting the laminated sheets in the thickness direction.

Then, as shown in FIG. 2, after forming the winding groove 20 in at least one of the core half bodies, in this embodiment, the core half body 18, the abutting surfaces 18a of both core half body blocks 18 and 19, 19a is polished, and a non-magnetic gap spacer 21 such as SiO ₂ is polished on the surface.
Is formed by a method such as a sputtering method (FIG. 3 (F)), and then, as shown in FIG. 2, both core half blocks 18 and 19 are glass at the joint surfaces 18a and 19a. Bonded to obtain the head core 1 consisting of a thin film laminated core.

As shown in FIGS. 1 and 2, the head core 1 manufactured in this way has a bonding glass layer 4 (4a, 4b, 4c) in the recess 3 of the slider 2 manufactured in a predetermined shape and size. )
And a composite type floating magnetic head are formed.

Here, according to the present invention, in the flying magnetic head having the above-mentioned structure, the slider 2 having excellent thermal matching property with the head core 1 and adhesion strength is further required, and further, wear resistance and precision machining. A material with good CSS property and excellent CSS resistance is also selected.

In general, the thermal expansion coefficient (α) of a Fe-Si-Al alloy magnetic body is
Since it is 135 to 150 × 10 ⁻⁷ / ° C., a material having such a coefficient of thermal expansion is also selected as the slider material from the viewpoint of thermal matching. In addition, the non-magnetic substrates 11 and 16 of the head core 1
Also, it is preferable that the slider is made of the same material as the slider from the viewpoint of thermal matching.

Al ₂ O ₃ which was previously considered to be the optimum slider material
-The thermal expansion coefficient (α) of TiC-based ceramic materials and CaTiO ₃ ceramic materials is 75-80 × 10 ^-7 /
C. and 100 to 115 × 10 ⁻⁷ / ° C., which has a large difference in thermal expansion coefficient from the Sendust thin film and cannot be used in the present invention.

The present inventors have studied to develop a slider material that can satisfy the above-mentioned various characteristics required for the present invention, and as a result, Co _X Ni
It has been found that an oxide having a composition of _2-X O ₂ (however, 0.2 ≦ X ≦ 1.8) is effective. Within this composition range, the coefficient of thermal expansion can be easily adjusted within the range of 128 to 150 × 10 ^-7 / ° C.
The hardness (Vickers hardness) is 550 to 600, which is close to the physical properties of Sendust. Further, as will be described later, according to the test result using the dummy slider, the CSS resistance of the ceramic itself was as good as that of the conventional ceramic slider material such as CaTiO ₃ .

Moreover, when the additive material is also examined, it is effective to add 0.1 to 5% by weight of at least one selected from MnO, TiO ₂ , Al ₂ O ₃ and CaO based on the above composition as a basic composition. It turned out that That is, MnO promotes sinterability, TiO ₂ and CaO bring about an increase in hardness, and Al ₂ O ₃ has an effect of suppressing coarse growth.

When Y ₂ O ₃ is added in an amount of 1 to 5% by weight, it has an effect of suppressing coarse growth, and when 0.1 to 1% by weight of TiN is added,
It brings about the case of hardness, and when 0.3-2% by weight of B ₂ O ₃ is added, it brings about the promotion of sinterability.

With these additives, the hardness becomes 600 to 700, which is closer to the value of Sendust, which is preferable.

Furthermore, mixed ceramics of Co _X Ni _2-X O ₂ (however, 0.2 ≦ X ≦ 1.8) and other oxides were also investigated, and MgO, CaO, Co
In mixed ceramics composed of O and NiO, Mg
O and CaO content of less than 30 mol% each and the balance Co
It has been found that even when it is composed of _X Ni _{2 -X} O ₂ (however, 0.2 ≦ X ≦ 1.8) and has a rock salt type structure, it can be preferably used in the present invention.

MgO and CaO are effective because they have the effect of promoting sintering, increase the hardness, and have the same coefficient of thermal expansion as CoO and NiO. Outside the above composition range, the thermal expansion coefficient is remarkably reduced,
It is not desirable because it causes segregation and lowers the density.

The inventors of the present invention produced a floating magnetic head by using the above-mentioned ceramics having a basic composition of CoO and NiO as a slider and a head core substrate, and found that the thermal matching between each member was extremely good and the adhesion strength was sufficient. I got something.

Next, one example of the ceramic material that can be used in the present invention will be specifically described below.

Example 1 CoO and NiO were used as raw materials and adjusted to have a CoNiO ₂ composition and mixed. This was calcined in N ₂ at 1000 ° C., and then pulverized with an ethanol wet ball mill for 22 hours. After crushing this crushed powder into CIP, 1 in O ₂
Sintered at 350 ° C.

The HIP treatment was performed at 1280 ° C. and 1000 Kg / cm ² for 1 hour.

The physical properties of the sintered body according to this example were as follows.

Density 6.5g / cm ³ Hardness (Hv) 700 Bending strength 30Kg / mm ² Average crystal grain size 6.8μm Thermal expansion coefficient 136 × 10 ^-7 / ℃ The coefficient of thermal expansion is determined by the composition of the material,
The characteristics of 128 to 150 × 10 ^-7 / ℃ were exhibited.

The flying magnetic head was manufactured by using the ceramic material manufactured as described above for the substrates of the slider and the head core.

Table 1 shows the test results of the materials of the flying magnetic head and the dummy slider manufactured by using the material of this example in comparison with the conventional example using CaTiO ₃ .

From Table 1, as described above, the floating magnetic head of the present invention had extremely good thermal matching between the respective members, sufficient adhesion strength, and improved CSS resistance.

Also, the CSS resistance of the ceramic material produced in this way
Also, according to the test results using the dummy slider, the CSS resistance was about the same as the result of testing the conventional CaTiO ₃ using the dummy slider. Thereby, CoO according to the present invention,
Ceramics with NiO as the basic composition are resistant to C
It was found that the SS property was good.

For the measurement of CSS resistance, a disc coated with a carbon film having a diameter of 3.5 inches was used.
The time cycle was such that the speed was increased to 00 rpm, held at 3600 rpm for 1 second, then reduced to 0 rpm in 4 seconds, stopped for 1 second, and restarted.

Although the floating magnetic head of the present invention has been described as a composite type in the above embodiments, the present invention
It can also be suitably embodied in a pseudo-monolithic type flying magnetic head as shown in FIG.

As shown in FIG. 7, the flying type magnetic head in this embodiment is constructed by integrally joining a head core 1 to a slider 2 via a gap spacer 21. Further, the alloy magnetic film 14 is manufactured on both the slider 2 and the head core 1 to form a magnetic circuit of the magnetic head. Next, an example of the manufacturing method will be described.

Also in this embodiment, the Fe-Si-Al alloy film is formed on the non-magnetic substrate 11 by the same manufacturing process as described with reference to FIG.
The nonmagnetic insulating film 12 and the nonmagnetic insulating film 13 are stacked a required number of times, and the alloy magnetic thin film 14 is formed on the substrate 11 as shown in FIG.
The outermost layer of the alloy magnetic thin film 14 is preferably the Fe-Si-Al alloy film 12. At this time, the total thickness (t) of the alloy magnetic thin film 14 is preferably 30 μm or less from the economical point of view.

Then, the laminated glass 15 on the alloy magnetic thin film 14 has a film thickness of 0.05 to
The non-magnetic substrate 16 made of the same material as the previous substrate 11 is bonded to the laminated glass 15 to form a magnetic core block 17 by sputtering at 0.5 μm. (Fig. 9). As laminated glass 15, SiO ₂ -Al ₂ O
_3- Na ₂ O based glass or SiO ₂ —B ₂ O ₃ —Na ₂ O based glass is preferable.

The magnetic core block 17 manufactured in this manner is the tenth
As shown in the figure, the laminated pieces are cut in the thickness direction and cut into a slider portion 2'and a head core portion 1 '.

As shown in FIG. 11, the head core portion 1'is formed with the winding groove 20 and then the head core portion 1'and the slider portion 2 '.
The abutting surfaces 1a 'and 2a' are polished, and a non-magnetic gap spacer 21 such as SiO _{2 is} formed on the surfaces by a method such as a sputtering method, and then shown in FIG. 11 by a chain line. As described above, the head core portion 1'and the slider portion 2'are glass-bonded at the abutting surfaces 1a 'and 2a' so that the alloy magnetic thin film 14 is aligned.

Next, as shown in FIG. 7, the head core portion 1'is cut and ground into a predetermined shape to obtain a head core 1 made of a thin film laminated core, and the slider portion 2'is also cut into a predetermined shape. The slider 2 is ground.

According to this embodiment, the alloy magnetic film 14 is formed on both the slider 2 and the head core 1 to form the magnetic circuit of the magnetic head.

Here, in the present invention, for example, the non-magnetic substrates 11 and 16 that substantially form the slider 2 are made of the same Co as described in the above embodiment.
A ceramic material having a composition of _X Ni _{2 -X} O ₂ (however, 0.2 ≦ X ≦ 1.8) and further containing an additive is used.

According to this example, the thermal matching property was extremely good and the adhesion strength was sufficiently obtained. Moreover, the wear resistance and the precision workability were also good, and the good CSS resistance was shown.

EFFECTS OF THE INVENTION The flying magnetic head according to the present invention configured as described above is excellent in thermal matching property and adhesion strength with a head core having a Fe—Si—Al alloy magnetic film, wear resistance, and precision machining. It also has good properties, and has the effect that the CSS resistance can be significantly improved.

[Brief description of drawings]

FIG. 1 is a partially enlarged detailed view of a composite type flying type magnetic head according to the present invention. FIG. 2 is a perspective view of a composite type floating magnetic head according to the present invention. FIG. 3 is a process drawing showing the method of manufacturing the head core. FIG. 4 is a perspective view showing the overall configuration of a composite type flying type magnetic head according to the present invention. FIG. 5 is a perspective view of a conventional ferrite type composite type flying type magnetic head. FIG. 6 is a perspective view of a conventionally proposed thin film laminated composite type floating magnetic head. FIG. 7 is a perspective view of a pseudo-monolithic floating magnetic head according to the present invention. 8 to 11 are process diagrams showing a method of manufacturing the floating magnetic head of FIG. 1: Head core 2: Slider 3: Groove recess of slider 4: Bonding glass layer 11, 16: Non-magnetic substrate 14: Multilayer magnetic thin film

Claims (4)

[Claims] 1. A levitation type magnetic head comprising a slider and a head core formed by laminating magnetic thin films on a non-magnetic substrate, wherein the magnetic thin film of the head core is Fe--Si--Al alloy magnetic. The film is made of Co _X N.
A flying magnetic head characterized by being made of a ceramic material represented by i _2−X O ₂ (where 0.2 ≦ X ≦ 1.8). 2. The slider is made of a ceramic material containing CoO and NiO as a basic composition and 0.1 to 5% by weight of at least one selected from MnO, TiO ₂ , Al ₂ O ₃ and CaO. The flying magnetic head according to claim 1, wherein 3. The slider has a basic composition of CoO and NiO of 1 to 5 wt% Y ₂ O ₃ , 0.1 to 1 wt% of TiN and 0.1.
The flying magnetic head according to claim 1, wherein the flying magnetic head is made of a ceramic material to which at least one of B ₂ O ₃ of _{3 to 2} % by weight is added. 4. The slider is a mixed ceramic having a composition of MgO, CaO, CoO and NiO, each containing MgO and CaO in an amount of 30 mol% or more, and the balance being Co _X Ni _2-X O ₂
The flying magnetic head according to claim 1, wherein the flying magnetic head is made of a ceramic material having a rock-salt structure, with 0.2 ≦ X ≦ 1.8.