JPH06349019A - Magnetic head - Google Patents

Abstract

PURPOSE:To improve contact with recording media and to prevent the generation of damages in substrates and films having magnetism. CONSTITUTION:Laminated films 3 are formed via metallic thin-film layers 13 consisting of metals, such as Ti, Cr, W, Zr and Mo, on the nonmagnetic substrate 121 consisting of cyrstallized glass and metal oxide thin-film layers 14 consisting of one or >=2 kinds of metal oxides such as SiO2, ZnO, Al2O3 and Ta2O5, are formed on the laminated films 3. The second nonmagnetic substrate 122 consisting of the same material as the material of the first nonmagnetic substrate 121 is joined onto these metal oxide thin-film layers 14 by the glassy material oozing from the crystallized glass constituting the substrate described above, by which first and second core half bodies 11a, 11b are formed. The end faces of the laminated films 3 of these first and second core half bodies 11a, 11b are butted via a nonmagnetic material to be formed as a magnetic gap 10, by which the magnetic head is constituted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head used in a magnetic recording device such as a VTR or a magnetic disk device.

[0002]

2. Description of the Related Art In recent years, as a magnetic head used in a magnetic recording device for handling a wide band signal such as a high definition VTR digital VTR, for example, a laminated core type magnetic as disclosed in Japanese Patent Laid-Open No. 62-119709. A head is proposed.

FIG. 8 is a perspective view showing the outer appearance of the conventional laminated core type magnetic head, and FIG. 9 is a view showing the medium sliding contact surface of the magnetic head.

In the figure, 1a and 1b are first and second core halves, and the first and second core halves 1a and 1b are first non-magnetic materials such as crystallized glass and non-magnetic ceramics. A laminated film 3 of a ferromagnetic metal film 4 made of a soft magnetic alloy such as an Fe—Al—Si alloy or an amorphous alloy containing Co as a main component and an insulating film 5 such as SiO ₂ on the magnetic substrates 21 and 21.
3 (a film having magnetism) is formed, and the second non-magnetic substrates 22 and 22 are bonded and fixed thereon by the sealing glasses 6 and 6. A glass-filled groove 7 is formed in the first core half 1a, and a winding groove 8 is formed in the second core half 1b. In the first and second core halves 1a and 1b, in the glass filling groove 7 and the winding groove 8 in a state where the surfaces on the gap forming side where the end surfaces of the laminated films 3 and 3 are exposed are butted against each other. Gap-bonding is performed by the second sealing glass 9 with which the upper end is filled, and a magnetic gap 10 formed by interposing SiO ₂ or the like is formed on the bonding surface.

However, in the above conventional magnetic head, the sealing glass 6 for bonding the second non-magnetic substrate 22 on the laminated film 3 has a softening point of 400 to 600 ° C.
A glass having a welding temperature of 500 to 800 ° C. at the time of glass bonding is used, and the sealing glass 6 of this type has the above-mentioned first and second sealing glasses.
Since the non-magnetic substrates 21 and 22 are inferior in chemical and mechanical durability, there is a problem that the sealing glass 6 is unevenly worn when the magnetic medium is slid at high speed for a long time. Further, in the glass bonding with the sealing glass 6, since bubbles are likely to be generated due to dirt on the bonding surfaces, holes are formed by the bubbles on the medium sliding contact surface, and a good magnetic head / magnetic tape running system is formed. There is also a problem that it cannot be obtained.

Further, when manufacturing the above-mentioned conventional magnetic head, since the thickness of the sealing glass 6 varies,
In the pair of blocks before cutting out the second core halves 1a and 1b, the stacking pitch of the stacked film 3 varies, and when the pair of blocks are butted to each other for gap bonding,
The laminated films 3 do not face each other, the track width varies, and the manufacturing yield deteriorates.

As a magnetic head which eliminates the above-mentioned drawbacks,
For example, there is one disclosed in Japanese Patent Laid-Open No. 4-61610.

In this magnetic head, a magnetic film is formed on a first non-magnetic substrate, and a second non-magnetic substrate is bonded on the magnetic film to form a pair of first and second core halves. The yield point of the second non-magnetic substrate is 500 to 800 ° C.
Of crystallized glass, the first non-magnetic substrate is made of crystallized glass having a sag point higher than that of the second non-magnetic substrate, and the second non-magnetic substrate is formed of the magnetic film. It is directly fusion-bonded on top. In this magnetic head, the second non-magnetic substrate is directly bonded to the magnetic film by the glass exuding from the crystallized glass forming the substrate by heating at the deformation point temperature. The soft bonding layer is not exposed between the magnetic film and the second non-magnetic substrate and the bubble is not generated.

However, also in this magnetic head, in order to match the mechanical strength of the first non-magnetic substrate and the second non-magnetic substrate, it is necessary to use a substrate whose sag points are close to each other. It is difficult to control the heating temperature and so on. Further, since it is impossible to completely match the mechanical characteristics of the first and second non-magnetic substrates, the wear of the first and second non-magnetic substrates on the medium sliding contact surface is uneven. There are also problems. Further, since it is impossible to completely match the thermal expansion coefficients of the first and second non-magnetic substrates, in the manufacturing process, the non-magnetic substrates may be deformed due to deformation after bonding or residual thermal stress. Cracks are produced and the magnetic film is peeled off, which deteriorates the manufacturing yield. Furthermore, since two types of non-magnetic substrates are used, it is necessary to strictly check each of them so as not to replace each other.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned drawbacks of the conventional example. The first and second non-magnetic substrates are formed with a magnetic film between them. In the magnetic head having the two core halves, the glass layer for bonding the substrate is exposed on the medium sliding contact surface, and uneven wear and holes due to air bubbles are generated on the medium sliding contact surface, resulting in poor contact with the magnetic medium. It is also possible to prevent the occurrence of cracks on the substrate and the peeling of the magnetic film, and to prevent the magnetic properties of the magnetic film from being deteriorated by the glass when bonding the substrates. It is an object of the present invention to provide such a magnetic head.

[0011]

The magnetic head of the present invention comprises:
Ti, C on the first non-magnetic substrate made of crystallized glass
A magnetic film is formed through a metal thin film layer made of a metal such as r, W, Zr, or Mo, and Si is formed on the magnetic film.
Forming a metal oxide thin film layer composed of one or more metal oxides such as O ₂ , ZnO, Al ₂ O ₃ and Ta ₂ O ₅ ;
A second non-magnetic substrate made of the same material as the first non-magnetic substrate is bonded onto the metal oxide thin film layer by vitreous material exuded from the crystallized glass forming the first and second substrates. Core half bodies are formed, and the end surfaces of the magnetic films of the first and second core half bodies are butted against each other via a non-magnetic material forming a magnetic gap.

[0012]

According to the above construction, the second non-magnetic substrate is directly fusion-bonded to the magnetic film by the glassy substance exuding from the crystallized glass forming the substrate, so that the magnetic property of the medium sliding surface is improved. The soft bonding layer is not exposed between the film having s and the second non-magnetic substrate. Furthermore, the first non-magnetic substrate and the second
Since the non-magnetic substrate is made of the same material, uneven wear of the medium sliding contact surface, cracking of the substrate, peeling of the magnetic film and the like caused by the difference in the characteristics of both substrates can be suppressed.
Further, when the second non-magnetic substrate is joined, the vitreous exuding from the second non-magnetic substrate is prevented from reacting with the magnetic film by the metal oxide thin film layer, The vitreous exuded from the non-magnetic substrate is prevented from reacting with the magnetic film by the metal thin film layer.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a perspective view showing the external appearance of a magnetic head of this embodiment, and FIG. 2 is a view showing a medium sliding contact surface of the magnetic head. The same parts as those in FIGS. 8 and 9 are designated by the same reference numerals. I will omit the explanation.

In the magnetic head of this embodiment, the first and second core halves 11a and 11b are respectively the first non-magnetic substrate 12
1. High melting point metal thin film layers 13 and 13 are formed on 1, 121, laminated films 3 and 3 are formed on the metal thin film layers 13 and 13, and metal oxide thin films are formed on the laminated films 3 and 3. Layers 14, 1
4 is formed, and second non-magnetic substrates 122 and 122 are bonded on the metal oxide layers 14 and 14. The metal thin film layers 13 and 13 are made of Ti, Cr, W, Zr, Mo or the like.
It is made of a kind of metal and has a film thickness of 500 to 5000 Å. The metal oxide thin film layers 14 and 14 are made of Si.
O _2, ZnO, consists _{Al 2 O 3, Ta 2 O} 5 1 kind or 2 or more metal oxides such as, having a thickness of 500 to 5000 Å. The first and second non-magnetic substrates 121 and 122
Are both made of the same crystallized glass, and specifically, they are made of Li ₂ O—SiO ₂ type crystallized glass. And the characteristic of this crystallized glass is that the coefficient of thermal expansion is 120 ×
10 ^-7 / ° C, yield point 640 ° C, density 2.52 g / c
m ³ , Vickers hardness is 580 kg / mm ² , and bending strength is 2200 kg / cm ² .

The second non-magnetic substrates 122 and 122 are
It is directly bonded and fixed onto the metal oxide thin film layers 14 and 14 by vitreous material exuded from the crystallized glass constituting the substrate by heating at the sag point. At this time,
Since the metal oxide thin film layer 14 has a good reaction with the glassy substance exuded from the crystallized glass, the metal oxide thin film layer 14 is firmly bonded to the second non-magnetic substrate 122. Further, the metal oxide thin film layer 14 also serves to prevent the vitreous exuded from the crystallized glass from directly reacting with the laminated film 3 to deteriorate the magnetic characteristics of the laminated film 3. Further, when the second non-magnetic substrate 122 is joined by heating at its sag point, vitreous tends to exude from the crystallized glass forming the first non-magnetic substrate 121. The presence of the metal thin film layers 13 and 13 prevents the exuded glass from reacting with the laminated film 3 and deteriorating the magnetic characteristics of the laminated film 3.

The first and second non-magnetic substrates 121,
As the deformation point temperature of the crystallized glass forming 122,
650 ° C. or lower is desirable in order not to deteriorate the magnetic characteristics of the laminated film 3 even at the temperature at the time of substrate bonding (the temperature at this time is equal to the yield point temperature), while sufficient heat resistance is required at the time of gap bonding. Therefore, 550 ° C. or higher is desirable. That is, the first and second non-magnetic substrates 12
The yield point temperature of the crystallized glass constituting 1,122 is 55.
A temperature of 0 to 650 ° C is suitable.

Next, a method of manufacturing the magnetic head of the above embodiment will be described.

First, as shown in FIG. 3, a metal thin film layer 13 made of Ti, Cr or the like and having a thickness of 500 to 5000 Å is formed on the upper surface of a non-magnetic substrate 12 made of crystallized glass by sputtering or the like, and then the thin film layer 13 is formed. A laminated film 3 of a ferromagnetic metal film and an insulating film is formed on the upper surface by sputtering or the like in an amount of 5 to 20 μm.
m thickness is formed, and SiO ₂ , ZnO, A
A metal oxide thin film layer 14 of 500 to 5000 Å made of l ₂ O ₃ or the like is adhered and formed to form a laminated substrate 15.

Next, as shown in FIG. 4, the laminated substrate 1
A plurality of sheets of No. 5 are prepared and stacked, and the non-magnetic substrate 12 is placed on the uppermost surface thereof, and the stacked ones are heated to a deformation point temperature of 550 to 650 ° C. Then, by pressurizing and holding at 2 kg / cm ² for 1 hour, the vitreous substance is exuded from the crystallized glass, and the plural laminated substrates 15 are integrated by the glass bonding by the vitreous substance to form a laminated block 16 To form.

Next, the laminated block 16 is cut along broken lines aa 'and bb' shown in FIG. 5, and as shown in FIG. 6, a pair of first and second laminated head pieces. 17a,
17b is formed.

Next, as shown in FIG. 7, a glass filling groove 7 is formed on the gap forming side surface of the first laminated head piece 17a, and the gap forming side surface of the second laminated head piece 17b is formed. After forming the winding groove 8 in the first,
In the state where the gap forming surfaces of the second laminated head pieces 17a and 17b are butted against each other via the gap spacer, the sealing glass 9 and 9 having a low melting point whose melting temperature is lower than the deformation point temperature of the above-mentioned crystallized glass is used. The laminated head block 18 is formed by gap bonding.

Thereafter, the laminated head block 18 is cut to form a plurality of laminated head chips, and the laminated head chips are subjected to a predetermined shape processing to form a laminated core type magnetic head of this embodiment shown in FIG. Is completed. It should be noted that, by this cutting step, the non-magnetic substrate 12 becomes
21 and the second non-magnetic substrate 122.

In the magnetic head of this embodiment as described above,
The second non-magnetic substrate 122 is heated at the deformation point temperature of the crystallized glass forming the substrate so that the glassy substance exudes from the crystallized glass. It is directly bonded onto the metal oxide thin film layer 14 formed in the above. Therefore, there is no soft bonding layer between the laminated film 3 and the second nonmagnetic substrate 122.
Further, when heated at the deformation point temperature, no bubbles are generated from the crystallized glass, and no holes due to bubbles are generated on the medium sliding contact surface. Further, since the first and second non-magnetic substrates 121 and 122 are formed of the same crystallized glass, the first and second non-magnetic substrates 121 and 122 are evenly worn on the medium sliding contact surface. To do. Further, since the first and second non-magnetic substrates 121 and 122 have the same coefficient of thermal expansion, the first and second non-magnetic substrates 121 and 122 are bonded to each other due to residual thermal stress or the like. Non-magnetic substrate 1
There is no occurrence of cracks in 21 or 122 and peeling of the laminated film 3.

Further, when the second non-magnetic substrate 122 is bonded, the vitreous exuded from the first and second non-magnetic substrates 121 and 122 reacts with the laminated film 3 because of the reaction of the first non-magnetic substrate. Since the metal thin film layer 13 formed on the magnetic substrate 121 and the metal oxide thin film layer 14 formed on the laminated film 3 prevent this, deterioration of the magnetic characteristics of the laminated film 3 is also prevented.

Further, in the manufacturing method of this embodiment, the non-magnetic substrate 12 does not have its outer shape deformed by heating at the deformation point temperature of the crystallized glass forming the substrate, so that the lamination block 15 shown in FIG. The pitch of the films 3 can be defined with high accuracy by the thickness of the non-magnetic substrate 12, and the laminated films 3 of the first and second laminated head pieces 17a and 17b can be easily formed at the time of gap bonding shown in FIG. Highly accurate magnetic gap 10 that can be accurately opposed to each other.
Can be formed.

[0027]

According to the present invention, it is possible to prevent poor contact with a medium due to uneven wear or the like on the sliding surface of the medium, and to prevent heat from contacting the substrates or contact with the bonding glass. It is possible to provide a magnetic head that prevents damage to the magnetic film and deterioration of the magnetic characteristics of the magnetic film.

[Brief description of drawings]

FIG. 1 is a perspective view showing the appearance of a magnetic head of the present invention.

FIG. 2 is a diagram showing a medium sliding contact surface of the magnetic head of the present invention.

FIG. 3 is a perspective view showing a method of manufacturing a magnetic head of the present invention.

FIG. 4 is a perspective view showing a method of manufacturing a magnetic head of the present invention.

FIG. 5 is a perspective view showing a method of manufacturing a magnetic head of the present invention.

FIG. 6 is a perspective view showing a method of manufacturing a magnetic head of the present invention.

FIG. 7 is a perspective view showing a method of manufacturing a magnetic head of the present invention.

FIG. 8 is a perspective view showing the appearance of a conventional magnetic head.

FIG. 9 is a perspective view showing a medium sliding contact surface of a conventional magnetic head.

[Explanation of sign]

 3 laminated film (film having magnetism) 10 magnetic gap 11a first core half body 11b second core half body 121 first non-magnetic substrate 122 second non-magnetic substrate 13 metal thin film layer 14 metal oxide thin film layer

Claims (3)

[Claims] 1. A magnetic film is formed on a first non-magnetic substrate made of crystallized glass via a metal thin film layer, and a metal oxide thin film layer is formed on the magnetic film. A second non-magnetic substrate made of the same material as the first non-magnetic substrate is bonded onto the oxide thin film layer by vitreous material exuded from the crystallized glass forming the first and second cores. A magnetic head comprising a half body, and end faces of the magnetic films of the first and second core halves are butted against each other via a non-magnetic material serving as a magnetic gap. 2. The metal thin film layer is made of Ti, Cr, W, Z.
The magnetic head according to claim 1, which is made of a metal such as r or Mo. 3. The metal oxide thin film layer comprises SiO ₂ , Zn
_3. The magnetic head according to claim 1, wherein the magnetic head is made of one or more metal oxides such as O, Al ₂ O ₃ , Ta ₂ O _{5 and the} like.