JPS62145513A - Magnetic head - Google Patents

Abstract

PURPOSE:To prevent the generation of the loosened glass layer or core deviation during the adhesion of a gap of a magnetic head having the construction in which both sides of a magnetic material are sandwiched by substrates by constituting the adhesive layer thereof a specific material. CONSTITUTION:An amorphous alloy layer 7 is formed as a soft magnetic metallic film by an apparatus for manufacturing the thin film by sputtering onto the surface of the substrate 6 finished to a specular surface and further a polymer is coated on the opposite side surface of a substrate material 8. The polymer is a polymer crosslinked with an org. metal in which the polycarboxilane part consisting of carbosilane skeleton is crosslinked and bound by a titanium compd. An optional density and viscosity are obtd. by dilution and the polymer is prepd. according to purposes. Both are then superposed in such a manner that the amorphous alloy film 7 and the polymer layer 9 face each other and are cured by heating while pressure is exerted to the substrates 6 and 8. A winding window 11 is then formed and a gap spacer film 12 and welding glass film 13 for gap bonding are stuck to the necessary part of the butt surfaces of at least one side faces of a set of the core blocks 10, 10'.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates to a magnetic head using a head core having a structure in which a magnetic material is sandwiched between substrates.

Conventional technical materials Ferrite has been widely used as the core 1 for magnetic heads due to its good wear resistance, but its saturation magnetic flux density is 30 to 60% lower than that of alloy materials.
When used in high-density recording media with high coercive force that have appeared in recent years, magnetic saturation of the head core material becomes a problem.

From this point of view, magnetic heads using alloy materials such as permalloy and sendust have been put into practical use as heads compatible with high-density recording media.

On the other hand, bi-amorphous alloys are attracting attention because they are materials with excellent scratch resistance and magnetic properties. Due to its manufacturing characteristics, amorphous alloy materials are suitable for making thin films of about 50 μm or less. Further, since metal materials have a much lower resistivity than ferrite materials, they have a large eddy current loss in the high frequency range, which is also advantageous.

However, when such a thin plate is used alone to form a magnetic head, there are problems in machining or strength. It is served to.

This time order is due to the adhesion between the magnetic material and the substrate material. Organic adhesives are easy to handle and can be heated for curing relatively easily, but in order to obtain practical strength, the adhesive layer needs to be thick enough to break (for example, on the order of tens of microns).
The reliability against changes in temperature and humidity after bonding is poor, and it is difficult to maintain custom-made heads with narrow gap lengths, such as heads for video tape recorders.

Therefore, when it comes to highly reliable bonding, glass bonding is currently the most reliable bonding method.

On the other hand, a case will be explained in which magnetic customization of an amorphous alloy is considered. FIG. 3 shows the σ-T curve.

Generally, as shown in FIG. 3, the magnetization becomes zero at the Curie temperature TC. The reason why magnetization appears again near the crystallization temperature Tx is because the magnetism of the crystalline alloy appears.

When considering the characteristics of the magnetic material of the magnetic head, the higher the magnetic permeability, the better, but in order to obtain high magnetic permeability, it is necessary to remove anisotropy in the magnetic film.

Therefore, to achieve this, T. The heat treatment may be performed in a temperature range higher than Tx and lower than Tx.

On the other hand, the above T. There is also a material in which Tx is reversed, but in the case of this material, high magnetic permeability cannot be obtained by normal heat treatment and special heat treatment such as heat treatment in a magnetic field is required, which poses a practical problem and is usually shown in Figure 3. Amorphous alloys with similar properties are used.

On the other hand, when considering the manufacturing process of a magnetic head using an amorphous alloy by glass bonding, at least two steps are necessary: a heat treatment step for bonding the substrate material and the amorphous alloy, and a heat treatment step for forming a gap.

Considering the loosening and movement of glass, it would be ideal if glass with a high softening temperature could be used to bond the substrate and amorphous alloy, and glass with a low softening temperature could be used to form a gap, but this should be considered from the perspective of eliminating anisotropy. Then, the final heat treatment step in the head manufacturing process needs to be at least at the same temperature as the previous heat treatment step or higher.

In addition, in practice, Tx is usually around 500°C;
o is 46, considering the magnetic flux density of the magnetic head material.
The temperature will be around 0℃ or higher.

Therefore, considering practical materials, T. The current new melting point lead glass is the only one because the temperature change range between -Tx cannot be made very wide and the working temperature is below T.

In order to lower the softening temperature, it is possible to increase the lead content in the glass, but if the lead content is increased, the glass itself will become unstable and its mechanical strength will also weaken, so the softening temperature cannot be lowered unnecessarily. is the current situation.

Against this background, new melting point glasses are currently being put into practical use (Japanese Unexamined Patent Publication No. 14313/1983).

Problems to be Solved by the Invention Although the substrate adhesion and gap forming glasses are the same, even if they are used differently, the softening temperatures are very similar for the above reasons.
The glass layer loosens when forming a gap when bonding the substrate/
) As shown in Figure 4, the gap accuracy is poor,
This causes core misalignment, resulting in a decrease in gear tooth clarity and a decrease in head yield.

Although FIG. 4 is schematically shown in an enlarged manner, the actual movement is on the order of microns. In the figure, a substrate 1 is bonded to a magnetic material 2 through a welded glass layer 3. The gap 4 is solid, but the welded glass layer 3 is loose.
Gap 5 has occurred.

The object of the present invention is to prevent the loosening of the glass layer or core shift during gap bonding, which occurs when conventional glass bonding techniques are used.

Means for Solving the Problems The adhesive layer between the magnetic material and the substrate material is made of an organometallic crosslinked polymer in which a polycarbosilane portion consisting of a carbosilane skeleton is crosslinked with a titanium compound, and silicon made by partially decomposing the above polymer. , titanium, charcoal action With the above structure, core displacement due to loosening or movement of the adhesive layer does not occur in the gap forming step, which is a heat treatment process, so that the head yield is dramatically improved.

Embodiment The structure of a magnetic head according to an embodiment of the present invention will be explained in accordance with the order of the head manufacturing process shown in FIG.

As shown in FIG. 1A, an amorphous alloy film 7 was formed as a soft magnetic metal film on the mirror-finished surface of the substrate 6 using a sputtering thin film forming apparatus. Furthermore, a polymer is applied to the surface of the substrate material 8 on the opposite side.

This polymer is an organometallic crosslinked polymer in which a polycarbosilane/moiety consisting of a carbosilane skeleton is crosslinked with a titanium compound. Any concentration and viscosity can be obtained by diluting it with an appropriate organic solvent, and it can be prepared according to the purpose. . This polymer can be applied using the blade method, spray method, or screen printing.

Any method such as brushing or spinner coating may be used.

The characteristics of the amorphous alloy film 7 are saturation magnetic flux density Bs-80o
O Gauss, crystallization temperature Tx = 560°C, Curie point TC
=450°C.

Thereafter, as shown in FIG. 1B, the upper and lower surfaces of the substrates 6 and 8 are aligned so that the amorphous alloy film 7 and the polymer layer 9 face each other. : 5, and was cured at 500°C in a non-oxidizing atmosphere. After being heated and hardened, it will not loosen even if it is reheated to a degree of 1-0'4 at least to the softening temperature. Adhesive layer thickness: Determined by the viscosity of the polymer and the applied pressure.

Considering the surface properties of the substrate and the strength of warpage and patterning, it is recommended that the thickness be 51 m or less, preferably 3 μm or less. Sled 2 has the advantage of completely covering even if there are irregularities or gaps on the surface.

As the temperature rises, polycarbosilane begins to volatilize from about 300°C, and mineralization progresses by sequential volatilization of H2, CH4:Th, and up to 1300°C, Si, Ti, and C
,O has an amorphous structure. Therefore, when heat-cured at about 50° C., a polymer and an amorphous substance consisting of Si, Ti, C, and O are mixed together.

Next, a winding window 11 is formed, and a set of core blows 10.
On at least one side surface of the core block 10', a gap spacer film 12 such as S 10'2 and a welded glass film 13 for gap bonding were attached to necessary portions of the abutting surfaces of the core blocks by a method such as sputtering. At this time, there is no problem even if the above-mentioned polymer is used in place of the spacer film 12 or the welded glass film 13 for gap bonding.

However, in order to obtain gap accuracy, it is necessary to control the film thickness of the incoming order, and with the current technology, sputtering is more difficult to control the film thickness. If the film thickness can be controlled to the same level as sputtering or the gap length is large, either method is fine.

Next, as shown in FIG. 1C, the spacer film 12 and the glass film 13 are brought together so as to face each other and heated. At this time, a bonding glass 14 is placed at the tip of the winding window 11 and simultaneously melted at 500° C. (gap formation).

At this time as well, the above polymer may be used instead of the bonding glass 14, but glass is superior in terms of bulk strength (when cured at 500°C).

In this way, a necessary gap 15 is formed as shown in the first diagram. Then, cut the line 16.16' to the predetermined core thickness.
Then, as shown in FIG. 1E, a tape sliding portion 17 is formed to complete the head chip.

Table 1 shows the yield of head chips obtained in this manner. For reference, conventional glass (softening temperature 450℃
and 500°C glass) are used in place of Polymer 9. The yields are also shown.

Note that the temperature for forming the core blocks 1o, 10' and the gap forming temperature (d) are the same for both materials.

Table 1 As is clear from Table 1, it can be seen that the head yield was dramatically improved by the present invention. The low yield of conventional examples is mainly due to poor adhesion due to loosening of the glass during gap formation for those with a softening temperature of 450°C, and peeling of the welded glass layer due to poor welding for those with a softening temperature of 500°C. .

FIG. 2 shows changes in head output due to the tape running and reversing of the head. The head of the present invention has no change in output even if it is repeatedly run, but the head with the conventional configuration (the softening temperature of the welded glass layer is 450'C) has a loosened welded glass layer as described above, and the amorphous alloy A gap is partially generated between the film 7 and the substrate 8, and tape residue adheres to the gap, resulting in a decrease in output due to spacing loss. The degree of adhesion of tape residue changes depending on the number of times the tape is repeated, resulting in a change in head output.

In the embodiments of the present invention, the method of forming an amorphous alloy film by sputtering has been described, but the method is not limited to sputtering, and vapor deposition methods can also be used.

Alternatively, a ribbon amorphous material obtained by ultra-quenching may be used.

However, in the case of ribbon amorphous, as shown in FIG. 4, a welded glass layer 3 corresponding to a single layer of the polymer of the present invention is arranged on both sides of the magnetic material 2.

Co-Fe-5i-B, Ni-3 as the amorphous alloy film
In addition to metal-metalloid systems containing St, B, C, P, etc., such as the i-B system, Co-metallic systems, which are metal-metal systems, have good wear resistance, high magnetic flux density, and high crystallization temperature. M (M is a metal element such as Nb, Ti, Ta, Zr, W, etc.) or Co-M'-M"(M',M" is the metal element shown by M above) system amorphous metal magnetic film is more preferable.

Furthermore, as described in the examples, if the polymer of the present invention is used in place of the welded glass film 13 and the bonding glass 14, bonding is possible at a temperature of about 25oC or higher, so especially for those with a low crystallization temperature. In this embodiment, a single layer of amorphous alloy film has been described, but it is more desirable to use a laminated core in which alloy films and interlayer insulating materials are alternately formed in order to prevent eddy current loss in the alloy film. In the examples, the description was limited to amorphous alloy films, but sendust alloys also have similar effects. However, since Sendust alloy is crystalline, it can be said that manufacturing is easier because there is no restriction on crystallization temperature.

Effects of the Invention According to the present invention, in a magnetic head having a structure in which both sides of a magnetic material are sandwiched between substrates, the adhesive layer is made of an organometallic crosslinked material in which a polycarbosilane portion consisting of a carbosilane skeleton is crosslinked with a titanium compound. polymer or silicon,
By using a substance made of titanium, carbon, and oxygen in an amorphous state, or a mixture of these polymers and an amorphous state, adhesion between the substrate and the magnetic material is achieved stably, and when a gap is formed, As a result of no loosening of the adhesive layer, the head yield during processing is dramatically improved, and since there is no tape residue adhering during tape running, stable head output can be obtained.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the manufacturing process of an embodiment of the magnetic head of the present invention, FIG. 2 is a characteristic diagram showing the output of the head of the present invention, and FIG. 3 is a characteristic diagram showing magnetization versus temperature of an amorphous alloy. , FIG. 4 is a front view showing the tape sliding surface of the conventional head configuration. 7...Amorphous alloy film, 6, 8...Substrate, 9...Polymer single layer. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure (E) Figure 2 Traveling Memories (@)

Claims (2)

[Claims] (1) Constructed using a composite of a magnetic material forming a magnetic core and a supporting substrate, at least a part of the joint of each component has a polycarbosilane part consisting of a carbosilane skeleton formed by a titanium compound. From a crosslinked organometallic crosslinked polymer, an amorphous substance consisting of silicon, titanium, carbon, and oxygen obtained by partially decomposing the above polymer, or a mixture of the above polymer and an amorphous substance. A magnetic head characterized by being provided with an adhesive layer. (2) The magnetic head according to claim 1, wherein an amorphous alloy or a sendust alloy is used as the magnetic material.