JPH0827909B2 - Magnetic head manufacturing method - Google Patents

Description

The present invention relates to a method of manufacturing a magnetic head for recording / reproducing information on / from a magnetic disk in a magnetic disk device.

More specifically, the present invention relates to a method of manufacturing a magnetic head called a floating type by being attached to a slider having an air bearing surface.

[Prior Art] In a magnetic disk device provided with a floating magnetic head, a magnetic head is arranged on a magnetic disk with a certain distance (called a flying height), and a magnetic circuit of the magnetic head (member constituting this circuit). Is called the core.) Recording and playback is performed. The flying height is forcibly created by the rotation of the disk. The air bearing surface (the member that makes this outside is called the slider) is arranged so that the cross section becomes a wedge shape in the air flow, and that surface is placed. A dynamic pressure is generated in and kept at that dynamic pressure. Therefore, the magnetic head is composed of two main parts, a slider having an air bearing surface for maintaining the flying height and a magnetic head chip for recording / reproducing.

The magnetic head is a magnetic material (for example, Mn-Zn ferrite)
A monolithic head in which a slider and a magnetic head chip are machined together by using a hard non-magnetic material (for example, Ca
It is roughly classified into a composite head in which a magnetic head chip made of a magnetic material is embedded in a slider of (TiO ₃ , Al ₂ O ₃ —TiC).

FIG. 2 is a perspective view showing an example of the composite head, and the magnetic head chip 1 is attached to the slider 2. The slider 2 has two air bearing surfaces 3 and 4. In this composite head, a slit 9 in the slider longitudinal direction is provided at the outlet end of the air flow flowing along the air bearing surface 4 of the slider 2, and the magnetic head chip 1 is inserted into the slit 9 and bonded with glass. Then buried. FIG. 3 shows a magnetic head chip 1
FIG. As shown in FIG. 3, the magnetic head chip 1 has a pair of cores 5 and 6 joined by a glass 7, and a gap 8 is formed between the cores 5 and 6. Reference numeral 10 is a winding window. In order to form this winding window 10, one core 5 has a linear rod shape, while the other core 6 has a C-shape. The core 5 is commonly called an I core, and the core 6 is commonly called a C core. The core 5,
6 consists of such as Mn-Zn ferrite ceramics sintered body to MnO, ZnO, and Fe ₂ O ₃ as a main component.

The disk medium is magnetized along the circumference of a certain radius, but in order to reduce the width of the donut-shaped magnetized portion (called the track width), the magnetic head chip 1 is separated from the disk before being inserted into the slit 9. The portion on the opposite side of is processed thin in advance (this processing is called track drawing processing).

Various shapes obtained by the track drawing process have been devised, and some of them are gradually thinned as shown in FIG. 5 so as not to obstruct the flow of magnetic flux due to a sudden change in the cross-sectional area.

There is also a shape in which the thickness is gradually reduced as shown in FIG. 4, but this is not preferable because the magnetic flux leaking to the side increases as indicated by arrow 11, and the magnetized portion of the medium bleeds in the track width direction.

Therefore, as shown in FIG. 3, the magnetic head chip of the composite head has a track diaphragm having a sectional shape protruding by a height (for example, 0.1 mm) that is the same as the track width (this diaphragm has a substantially stepped shape. Because it is called a step-type track diaphragm), it is mainly used. The core shown in FIG. 3 is called a step core.

In FIG. 3, the protruding portion is a thin piece-like portion.
80, and the other parts are thick-walled main body 90.

In the field of magnetic recording, studies are being made from both the medium and the head to increase the recording density.
Magnetic heads are used in the direction of narrower gaps and narrower tracks in response to higher coercive force of media, but conventional ferrite heads saturate the medium because the saturation magnetic flux density is about 5000G. It is becoming difficult to generate a sufficient head magnetic field. Therefore, as shown in FIG. 3, a ferromagnetic metal thin film (layer) 9 having a high saturation magnetic flux density is formed on the surface of the I core 5 that is coupled to the C core 6 (hereinafter, also referred to as a bonding surface). A magnetic head in which is deposited by a sputtering method has been used.

This magnetic head has the advantages that its structure is extremely simple and has excellent productivity, and that the track width can be set regardless of the film thickness of the ferromagnetic metal thin film 9.

However, in the magnetic head chip 1, since the boundary surface 16 between the core 5 and the ferromagnetic metal thin film 9 is positioned parallel to the magnetic gap 8, the boundary surface 16 is a pseudo gap (secondar).
It acts as a y gap) and causes deterioration of recording / reproducing characteristics. That is, as shown in FIG. 9, in addition to the reproduction output E ₁ by the gap 8, another reproduction output E ₂ is generated by this pseudo gap. For this reason, the frequency characteristic of the reproduction signal is wavily generated, which causes a reduction in reproduction output.

In order to eliminate the above-mentioned pseudo gap, JP-A-60-2292
As described in Japanese Patent No. 10, a ferromagnetic metal thin film is formed with a tilt of about 10 to 80 ° with respect to the magnetic gap and the pseudo gap is reduced by azimuth loss, or a groove or a groove is formed on the surface to which the ferromagnetic metal thin film is attached. A method has been proposed in which unevenness is provided so that the boundary surface with ferrite is not parallel to the magnetic gap. However, these methods have problems in terms of productivity and manufacturing cost.

Further, as disclosed in JP-A-63-39106 and JP-A-63-32709, a method of interposing a base film made of a high magnetic permeability material on the boundary surface between the magnetic core portion and the ferromagnetic metal thin film is known. Proposed. However, in this method, when an iron-aluminum-silicon-based (Fe-Al-Si-based) alloy thin film is used as the ferromagnetic thin film and a nickel-iron (Ni-Fe) underlayer film is used, due to heating during glass bonding, Ni is Fe-Al-
It has become more clear that it diffuses into Si (Proceedings of Applied Magnetics in '88), which deteriorates the characteristics of the magnetic film and cannot sufficiently reduce the pseudo gap.

Further, when a ferrite (Ni-Zn ferrite) containing nickel oxide, zinc oxide, and iron oxide is used as the underlayer film, it is difficult to stably produce an underlayer film that can obtain sufficient soft magnetism.

A non-magnetic chromium (Cr) film is applied to the ferrite core and Fe-
A method for preventing the reaction between the ferrite and the Fe-Al-Si film by interposing it between the Al-Si film and the Al-Si film has also been proposed (JP-A-63-31).
1611, JP-A 64-1109).

That is, in the claims of JP-A-61-311611,
"In a composite magnetic head in which at least the vicinity of the working gap of the magnetic core mainly composed of ferromagnetic oxide is made of a metal magnetic material, a ferromagnetic oxide surface with a strain-free high flatness surface has a thickness of 100 Å to 1000 Å A composite magnetic head having a metallic magnetic material in which a Cr thin film and an Fe-Al-Si alloy thin film are laminated in this order. " In the range, “(1) In a magnetic head in which a ferromagnetic metal thin film is formed in the vicinity of a magnetic gap by a vacuum thin film forming technique, and a rear magnetic path is formed with a ferromagnetic oxide so as to sandwich the ferromagnetic metal thin film, A magnetic head characterized in that a non-magnetic element film is formed between the metal thin film and the ferromagnetic oxide (2) The non-magnetic element film contains Cr or Ti. (3) The non-magnetic element The first claim of the magnetic head thickness of characterized in that it is a 200～2000A. "Is described.

As is clear from these claims, JP-A-63-
In the magnetic heads of 311611 and 64-1109, the Cr layer remains between the Fe-Al-Si film and the ferrite core.
However, the pseudo gap could not be reduced by these methods. That is, the magnetic permeability of Cr itself is 1,
The remaining Cr layer acts as a pseudo gap layer.

As described above, the method of interposing the base film made of a high magnetic permeability material or a non-magnetic material also has problems in reliability, manufacturing cost, and productivity.

[Problems to be Solved by the Invention] As described above, in the magnetic head in which the ferromagnetic metal thin film is formed in parallel with the magnetic gap, the productivity and the accuracy are excellent, but the influence of the pseudo gap is large. There is a problem with reliability. In a magnetic head in which a ferromagnetic metal thin film is formed obliquely with respect to the magnetic gap, or in a magnetic head in which a base film made of a high magnetic permeability material or a nonmagnetic material is interposed at the interface between the magnetic core portion and the ferromagnetic metal thin film, There was a problem in terms of productivity and manufacturing cost.

Further, even when the chromium layer is formed between the core and the Fe-Al-Si thin film layer, it is difficult to reduce the pseudo gap.

The object of the present invention is to utilize the characteristics of a magnetic head in which a ferromagnetic metal thin film is formed parallel to a magnetic gap,
An object of the present invention is to provide a method of manufacturing a magnetic head which suppresses the influence of a pseudo gap generated between a magnetic core part and a ferromagnetic metal thin film and is excellent in reliability and productivity.

[Means for Solving the Problem] In the method of manufacturing a magnetic head according to claim (1), a pair of ferrite cores are arranged so as to oppose each other with a magnetic gap therebetween, and at least one of the cores has a strong metal surface. In a magnetic head on which a magnetic alloy film is formed, chromium is sputtered on the surface of one of a pair of ferrite cores to be bonded by glass on the bonding side to form a chromium layer, The step of forming a layer of chromium oxide having a thickness of 3 to 100Å between the chromium layer and the ferrite by combining with oxygen in the ferrite, and the sputtering of the next step without contacting the chromium layer with an oxidizing atmosphere. During the steps of forming a thin film of iron-aluminum-silicon alloy on the chromium layer and bonding the pair of ferrite cores with glass. Diffused in the iron-aluminum-silicon alloy thin film layer,
And a step of bringing the alloy layer into direct contact with the chromium oxide layer.

According to a second aspect of the present invention, there is provided a magnetic head manufacturing method, wherein a pair of ferrite cores are arranged so as to face each other with a magnetic gap therebetween, and a metal ferromagnetic alloy film is formed on the facing surface of at least one of the cores. In the head, a metal ferromagnetic alloy film is formed on at least one core of a pair of ferrite cores bonded by glass, and chromium is sputtered on the surface of the core to be bonded to form a chromium layer, A step of combining chromium and oxygen in the ferrite to form a layer of chromium oxide having a thickness of 3 to 100Å between the chromium layer and the ferrite, and the following step without contacting the chromium layer with an oxidizing atmosphere. Sputtering is performed to deposit iron on the chromium layer.
One of a step of forming a thin film of an aluminum-silicon alloy and a step of heat treatment to diffuse chromium into the iron-aluminum-silicon alloy layer so that the alloy layer is in direct contact with the chromium oxide layer, Glass between the core and the other core, and heating to bond the cores to each other by the glass.

A method of manufacturing a magnetic head according to claim (3) is based on claim (1).
Alternatively, in (2), the steps from the chromium sputtering step to the step of forming the iron-aluminum-silicon alloy thin film are performed in an atmosphere of a total oxygen partial pressure and a water pressure of less than 10 ^-1 Pa. .

[Operation] By forming a chromium oxide layer between the ferrite core portion and the ferromagnetic alloy film, the reaction between the two is suppressed. This chromium oxide layer prevents mutual diffusion of oxygen atoms, aluminum atoms, and manganese atoms, which are easily diffused.

According to the present invention, when a chromium film is formed on a ferrite core by sputtering, a partial reaction occurs at the boundary between chromium and the ferrite material to form a chromium oxide layer. This chromium oxide layer may grow on subsequent heating. The thickness of this chromium oxide layer is at least 3Å
Is necessary, and 100Å to avoid the pseudo gap
Must be: The thickness of this chrome oxide layer is 10Å
With the above, it seems that the mutual diffusion of oxygen atoms, aluminum atoms, and manganese atoms can be completely prevented.

As the ferromagnetic alloy film, a material having a higher saturation magnetic flux density and a higher magnetic permeability than the ferrite material is used. An iron-aluminum-silicon ferromagnetic alloy film usually called sendust having a thickness of 0.5 to 20 μm is used.

In the present invention, metallic chromium is sputtered onto the ferrite surface to thin the chromium oxide layer as described above. An oxidation layer of chromium is formed by the oxidation reaction at the boundary of the metallic chromium attached to the ferrite.
When a ferromagnetic alloy film is formed on this metallic chromium and then heated, the metallic chromium diffuses into the alloy film, and only the chromium oxide layer generated above remains at the boundary between the ferrite and the ferromagnetic alloy film, and extremely It will be thin. The thickness of the chromium metal deposited in advance needs to be a certain thickness. If it is too thin, it is scattered or islets (isla).
nds form) and the ferrite and alloy film are directly attached. Therefore, the required thickness of chromium is sufficient to cover the entire surface of the ferrite core to which the alloy film is attached. Even if the thickness of chromium is a little thick, there is no problem because the part that has not become an oxide will diffuse into the alloy, and if the Cr content in the alloy is less than 4 wt%, desirably less than 2 wt%, the corrosion resistance is improved. It is desirable from the aspect of doing.

Thus, in order to diffuse chromium into the alloy, it is necessary to perform all sputtering under the condition that the surface of chromium is not oxidized. Although the conditions vary depending on the temperature, the total of oxygen partial pressure and moisture pressure is generally less than 10 ^-1 Pa, preferably less than 10 ^-2 Pa at 400 ° C or lower where sputtering is usually performed.

EXAMPLES Examples of magnetic heads to which the present invention is applied will be described below with reference to the drawings.

FIG. 1 is an enlarged perspective view showing an example of a magnetic head to which the present invention is applied, and FIG. 6 is an enlarged plan view showing its magnetic recording medium facing surface.

In this magnetic head, the magnetic core parts 5 and 6 are Mn-Zn
A chromium oxide layer 12 formed of ferrite and having a thickness of 3 to 100 Å is formed on the joint surface of the magnetic core 5. A Fe—Al—Si thin film 9 in which Cr is diffused continuously is formed in direct contact with the chromium oxide layer 12 from the front gap forming surface to the back magnetic head forming surface.

Incidentally, FIGS. 1 and 6 are schematic views, and the chromium oxide layer 12 and F
The e-Al-Si layer 9 is also shown with some thickness. However, these thicknesses are 3 to 100 Å or several μm or less, and it is obvious that they cannot be discriminated by the naked eye.

 A method of manufacturing this magnetic head will be described below.

First, the I core 5 and the C core 6 are separately formed using Mn-Zn ferrite. Next, the I core is put into a sputtering device, and chromium (Cr) is sputtered on the joint surface of the I core. This sputtering preferably results in a thickness of 20.
~ 400Å, particularly preferably 50 ~ 150Å to form a Cr layer. At this time, oxygen (O) in the ferrite reacts with Cr, possibly due to the energy of collision of Cr atoms with the ferrite surface, and chromium oxide A layer is formed at least in part.

After forming the Cr layer, the Cr layer is subjected to sputtering in the next step without exposing it to an oxidizing atmosphere such as the air, and an Fe-Al-Si alloy layer is preferably formed on the Cr layer in an amount of 0.5 to 20 μm, particularly preferably 1. It is formed to have a thickness of ˜5 μm.

Next, Cr is diffused into the Fe-Al-Si layer by heat treatment to eliminate the Cr layer. At this time, it is considered that the chromium oxide layer at the boundary between the ferrite and the Cr layer also increases. The heat treatment temperature is preferably 640 to 730 ° C., and the treatment time is preferably 10 minutes or longer, more preferably 20 minutes or longer. As a result, the Fe-Al-Si layer 9 containing Cr is formed so as to be in direct contact with the chromium oxide layer 12.

This I-core 5 is then joined to the C-core 6 by the glass 7. This glass has a softening point more than that used when fixing the magnetic head to the slider.
Use the one with the highest price. The reason for this is to prevent the glass 7 connecting the I core and the C core from softening when heated to fix the magnetic head to the slider.

In the present invention, after the Fe-Al-Si layer is formed on the Cr layer, the heat treatment only for Cr diffusion is not performed, but instead the I core and the C core are heated for glass bonding. Alternatively, the Cr layer may be diffused into the Fe-Al-Si layer so that the chromium oxide layer directly contacts the Fe-Al-Si layer containing Cr. In this way, the number of heat treatment steps is reduced by one.

The temperature for glass bonding cores is 640 ~ 7
30 ° C is preferred. When Cr is diffused at the time of glass bonding, the heating time is preferably 10 minutes (min) or more, particularly 20 minutes or more so that Cr is sufficiently diffused in the Fe-Al-Si layer.

A magnetic alloy thin film having a high magnetic permeability may be formed on the surface of the C core 6 on the mating side with the I core 5.

Suitable Fe-Al-Si-based magnetic alloys used in the present invention include those having a weight percentage of Al: 2 to 10%, Si: 3 to 16%, and the balance being substantially Fe. 4 ~ 8%, Si: 6 ~
Particularly preferred is 11% with the balance being substantially Fe.

In addition, even if each contains 2% or less of Ti and Ru,
Corrosion resistance and abrasion resistance can be improved, which is preferable.

In addition, as a constituent material of the C core and the I core, Mn-Zn ferrite, Ni-Zn ferrite and the like are preferable. The preferred composition of the Mn-Zn ferrite is MnO: 25-37 in mol%.
%, ZnO: 8~23%, Fe 2 O 3: 51~57% , and the like.

Si is used as the glass for connecting the C core and the I core.
O ₂ -PbO-R ₂ O (R is an alkali metal) glass or SiO _{2-
PbO-R 2 O-B 2} O 3 based glass is preferred. Particularly preferable compositions are exemplified below. This glass has a softening point of 560-580 ℃
Is.

SiO ₂ 28 to 49 wt% B ₂ O _{3 5 to} 15 wt% Na ₂ O 7 to 13 wt% PbO balance PbO-SiO ₂ -Al ₂ O ₃ -B ₂ O is used as the glass to bond the magnetic head to the slider. ₃ type glass is suitable, and particularly preferable compositions are as follows.

PbO 70-83wt% Al ₂ O ₃ 3-10wt% SiO ₂ 6-13wt% B ₂ O ₃ 4-10wt% The softening point of this PbO-based glass is 410-450 ° C.
Is.

Hereinafter, the present invention will be described in more detail with reference to manufacturing examples.

Example 1 The I core 5 is placed in a sputtering apparatus having a high performance exhaust system. After exhausting this system to the following conditions, the metal Cr
(Purity of 99.99% or more) and Fe-Al-Si alloy are sequentially formed.

<Exhaust characteristics> H ₂ O partial pressure <10 ^-3 Pa O ₂ partial pressure <10 ^-3 Pa Core temperature = 300 ° C <Sputtering condition> Sputtering power = 1 KW Cr film thickness 80 Å Fe-Al-Si film thickness 2.5 μm Further, the core was subjected to a heat treatment at a temperature between 700 ° C. for 30 minutes to complete the diffusion of Cr. This allows
The magnetic core 5 having the Fe-Al-Si film in which Cr is diffused is manufactured.

Next, SiO ₂ 35 wt%, B ₂ O ₃ 10 wt%, Na ₂ O ₃ 10 wt%
% And the balance PbO, and the I core and the C core were joined using glass having a softening point of 570 ° C. This heating temperature is 700
° C., time 60min, the atmosphere is N _2.

FIG. 6 is an enlarged view of the principal part of the surface of the manufactured magnetic head facing the magnetic recording medium. FIG. 7 is a graph showing the results of measuring the distribution of Mn and Cr along the line AA in the region shown in FIG. From this measurement, it was confirmed that a chromium oxide layer having a thickness of about 25 Å was formed at the boundary portion 13 between the ferrite core 5 and the Fe-Al-Si film in FIG. Cr
It was confirmed that the layer did not exist at all and Cr was diffused in the Fe-Al-Si film 9.

That is, the chromium oxide layer is in direct contact with the ferrite core 5 and the Fe-Al-Si alloy layer 9 containing Cr. The composition of the core used was MnO: 31 mol%, ZnO: 16
Mol%, balance Fe ₂ O ₃ , Fe-Al-Si alloy is Al: 6 wt
%, Si: 9 wt%, and the balance Fe.

Example 2 In Example 1, the temperature of the core during Cr sputtering was
At 300 ° C, the sputtering power was set to 2KW, and the Cr film thickness was set to
A magnetic head was manufactured in the same manner except that it was set to 200 Å.

As a result, the thickness between the I core and the Fe-Al-Si alloy is 50
A magnetic head having a Å chromium oxide layer formed was manufactured.

Example 3, Comparative Example 1 A magnetic head was manufactured in the same manner as in Example 1 except that the core temperature and sputtering power during sputtering were the same as those in Example and the heating time during glass bonding was as follows. Part of the metallic chromium becomes chromium oxide, and part of it remains as metallic chromium.
It was formed between the Fe-Al-Si alloys and in contact with them. The film thickness of the non-magnetic layer was as shown in the following table.

The pseudo gap peak ratios of the magnetic heads manufactured in Examples 1 to 3 and Comparative Example 1 were measured. The results are shown in Table I. The pseudo gap peak ratio is the percentage of the ratio E ₂ / E ₁ between the reproduction output peak E ₁ due to the gap and the reproduction output peak E ₂ due to the pseudo gap as shown in FIG. The reproduction output was measured using a hard disk with a coercive force of 80KAT / m and E ₂ / E ₁ of 12
It was read from an isolated playback waveform measured at 5 KHz.

As described above, it is clear that when the chromium oxide layer (non-magnetic layer) is formed to 100 Å or less, the pseudo gap peak ratio is extremely small and the noise is significantly reduced. It is also recognized that when the non-magnetic layer exceeds 100Å, the pseudo gap peak ratio becomes considerably large.

Comparative Examples 2, 3 and 4 In Examples 1, 2 and 3, after the Cr layer was formed on the I core, the I core was exposed to the atmosphere. After that, of this I core
An Fe-Al-Si based alloy layer was formed on the Cr layer. Other conditions were the same as in Examples 1, 2 and 3 to manufacture a magnetic head.

FIG. 8 is an analysis diagram similar to FIG. 7 of the magnetic head manufactured in Comparative Example 2. As shown in FIG. 8, in Comparative Example 2, Cr did not diffuse and remained as a Cr layer. The thickness of the residual Cr layer was consistent with the thickness of the sputtered Cr layer.

The pseudo gap peak ratio of each magnetic head was measured. The results are shown in Table II below.

As is clear from Tables I and II, when the Cr layer remains, the pseudo gap peak ratio becomes significantly large and the noise of the magnetic head becomes large.

Example 4 Various magnetic heads having a Cr film thickness formed on the I core between 50 and 500 Å were manufactured in the same manner as in Example 1.
In each magnetic head, a chromium oxide layer having a thickness of about 10 to 40Å was formed between the I core and the Fe-Al-Si alloy layer, and the Cr layer did not remain. The measurement results of the pseudo gap peak ratio (%) of each magnetic head are shown in FIG.

Comparative Example 5 Various magnetic heads having a Cr film thickness formed on the I core between 30 and 500 Å were manufactured in the same manner as in Comparative Example 1.
A Cr layer remained between the I core and the Fe-Al-Si alloy layer, and the thickness of the residual Cr layer was the same as the thickness of the formed Cr layer. The measurement results of the pseudo gap peak ratio (%) of each magnetic head are also shown in FIG.

Comparative Example 6 Fe-Al- was directly formed on the I core without forming a Cr layer.
A magnetic head was manufactured in the same manner as in Example 1 except that the Si-based alloy layer was formed. The measurement result of the pseudo gap peak ratio (%) is shown in FIG.

As is clear from FIG. 5, when the Cr layer remains, the pseudo gap peak ratio becomes more than twice as large as that when the Cr layer is diffused and disappeared. That is, when Cr remains, since the magnetic permeability of Cr is 1, the Cr layer itself acts as a pseudo gap and the pseudo gap peak ratio becomes large.
The influence of the residual Cr layer on the pseudo gap peak ratio becomes more remarkable as the thickness of the residual Cr layer increases.

When the Auger analysis was performed on the magnetic head of Comparative Example 6 in which the Cr layer was not formed, A of about 500 to 1000Å
It was confirmed that the oxide layer of l and the oxygen deficient layer of ferrite were formed at the interface between the core and the ferrite layer. Due to the pseudogap generated by this reaction, the pseudogap peak ratio reaches 13%.

After forming the Cr layer on the core, if the Fe-Al-Si film is formed by sputtering without exposing the Cr layer to an oxygen-containing atmosphere such as the air, the Fe-Al-Si film and the Mn-Zn ferrite are separated. Adhesion is significantly increased.

The measurement results between the two films are shown in Table III. The adhesive force is a value obtained by the scratch method.

The values in Table III show the load at which the Fe-Al-Si film peels off. Table I
As is clear from II, in the absence of the Cr underlayer, a very small adhesion of 5 to 9 N is obtained and the mechanical strength is weak, so the yield during head manufacture is also very low.

On the other hand, when a Cr thin film is formed in the range of 30 to 500Å and diffused, the adhesive force is significantly increased to 26 to 40N. This Cr layer eventually diffuses and disappears in the Fe-Al-Si alloy, but this Cr layer was firmly adhered to the core via the chromium oxide layer, and The Cr-containing Fe-Al-Si layer is firmly adhered via the chromium oxide layer.

As described above, the manufacturing method of the present invention can suppress the pseudo gap and increase the mechanical strength, and is therefore a method very suitable for a composite type head. In this example, after the Cr underlayer film and the Fe-Al-Si film are continuously formed, the heat treatment is performed to diffuse the Cr component and further glass bonding is performed. It was confirmed that the same result can be obtained even under the conditions.

[Effect of the Invention] According to the magnetic head manufactured by the method of the present invention,
The effect of the pseudo gap at the interface between the magnetic core and the ferromagnetic metal thin film, which could not be reduced without the use of azimuth loss and the underlying film made of a high-permeability material, was reduced by Fe-Al-Si in the Cr thin film. It can be significantly reduced by diffusing into a thin film.

Since this magnetic head has a simple structure and a simple manufacturing method, there are advantages that the manufacturing cost can be reduced and high reliability can be secured.

According to the method of manufacturing a magnetic head of the present invention, the above magnetic head can be manufactured easily and at low cost. Further, a magnetic head having high adhesion strength between the core and the ferromagnetic alloy layer and having high reliability can be manufactured.

[Brief description of drawings]

FIG. 1 is an external perspective view of a magnetic head to which the present invention is applied, FIG. 2 is a perspective view of a slider, FIGS. 3, 4, and 5 are perspective views of a conventional magnetic head, and FIG. FIG. 7 is an enlarged view of the medium facing surface of the head, FIGS. 7 and 8 are element distribution diagrams of the core junction, FIG. 9 is a reproduction output waveform diagram, and FIG. 10 is a pseudo gap peak ratio measurement diagram. 1 ... Magnetic head chip, 5,6 ... Core, 9 ... Fe-Al-Si alloy layer, 12 ... Chromium oxide layer.

Front page continuation (72) Fumio Futanda, 5200 Mikajiri, Kumagaya, Saitama Prefecture, Research Institute for Magnetic Materials, Hitachi Metals Co., Ltd. In-house (56) Reference JP 62-145510 (JP, A) JP 63-311611 (JP, A) JP 64-1109 (JP, A) JP 63-195813 (JP, A) Japanese Patent Laid-Open No. 1-100714 (JP, A)

Claims (3)

[Claims] 1. A magnetic head in which a pair of ferrite cores are arranged so as to face each other via a magnetic gap, and a metal ferromagnetic alloy film is formed on the facing surface of at least one of the cores. Chromium is sputtered on the surface of one of the pair of ferrite cores on the side to be bonded to form a chromium layer, and chromium is bonded to oxygen in the ferrite to form a space between the chromium layer and the ferrite. A step of forming a layer of chromium oxide having a thickness of 3 to 100 Å, and sputtering of the next step without contacting the chromium layer with an oxidizing atmosphere to form an iron-aluminum-silicon alloy thin film on the chromium layer. During the step of forming and the step of bonding the pair of ferrite cores with glass, chromium is diffused into the iron-aluminum-silicon alloy thin film layer to form an alloy layer. Preparation of magnetic head comprising the steps of a contact directly to the chromium oxide layer. 2. A magnetic head in which a pair of ferrite cores are arranged so as to face each other with a magnetic gap therebetween, and a metal ferromagnetic alloy film is formed on the facing surface of at least one of the cores. A metal ferromagnetic alloy film is formed on at least one of the pair of ferrite cores. A chromium layer is formed by sputtering chromium on the surface of the core on the side where the cores are joined, and chromium and oxygen in the ferrite are separated. A step of forming a chromium oxide layer having a thickness of 3 to 100 Å between the chromium layer and the ferrite by combining them, and performing a sputtering step in the next step without contacting the chromium layer with an oxidizing atmosphere to form a chromium layer on the chromium layer. And a step of forming a thin film of an iron-aluminum-silicon alloy on the surface of the iron-aluminum-silicon alloy to form a chromium oxide layer. Preparation of magnetic heads which is interposed a glass, comprising and a step of attaching the core comrades of glass heated between a step of the contact with the contact, and one core and the other cores. 3. The method according to claim 1 or 2, wherein the total of oxygen partial pressure and water pressure is 10 ⁻¹ Pa from the step of sputtering chromium to the step of forming a thin film of iron-aluminum-silicon alloy. A method of manufacturing a magnetic head, characterized in that the magnetic head is performed in an atmosphere of less than