JPH06150248A - Magnetic head - Google Patents

Abstract

PURPOSE:To improve the mechanical strength of a magnetic head by strongly gap-bonding first and second core half bodies. CONSTITUTION:This magnetic head has a pair of first and second core half bodies 11a, 11b constituted by forming a laminated film 3 on a first non- magnetic substrate 121 composed of a glass-ceramic and by bonding a second non-magnetic substrate 122 composed of glass-ceramic onto the laminated film 3, and is consituted by mutually butting and gap-bonding the surfaces on the gap-forming side of the first and second core half bodies 11a, 11b, where the end faces of said laminated film 3 are exposed, via non-magnetic material being a gap spacer. The first core half body 11a has a glassy layer 14 containing a vitreous material including a crystalline material in the surface on the gap- forming side of said first and second non-magnetic substrates 121, 122 and said first and second core half bodies 11a, 11b are gap-bonded by the glassy material oozing from the vitreous layer 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head suitable for efficiently recording and reproducing high frequency signals.

[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. 12 is a perspective view showing the external appearance of the conventional laminated core type magnetic head, and FIG. 13 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. On the magnetic substrates 21 and 21, the ferromagnetic metal film 4 such as sendust and Si
Laminated films 3 and 3 with an insulating film 5 such as O ₂ are formed and formed, and second non-magnetic substrates 22 and 22 are bonded and fixed by sealing glasses 6 and 6 thereon. The first core half 1a
A glass filling groove 71 is formed in the first core half 1b, and a glass filling groove 72 and a winding groove 8 are formed in the second core half 1b. The first and second core halves 1a and 1b are in the glass filling grooves 71 and 72 and the winding groove in a state in which 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. The second sealing glass 9 filled in the upper end of the gap 8 is gap-bonded, and a magnetic gap 10 formed by interposing SiO ₂ or the like is formed on the bonding surface.

The sealing glass 6 for bonding the second non-magnetic substrate 22 on the laminated film 3 has a softening point of 500.
~ 600 ℃, glass welding temperature is 600 ~ 700
No. 2 used for gap junction
The sealing glass 9 has a lower melting point (softening point of 350 to 450 ° C.) than the sealing glass 6 in order to prevent deformation due to remelting of the sealing glass 6 during gap bonding.
The sealing glass 6 having a low melting point is heated to 450 to 500 ° C., which is 50 to 100 ° C. higher than the softening point, and melted to perform the gap bonding.

However, in the above-described conventional magnetic head, the gap bonding is performed by melting the sealing glass 9, so that bubbles are generated in the sealing glass 9 due to contamination of the bonding surface during the melting, There is a problem that sufficient gap bonding strength cannot be obtained due to bubbles. Further, such a low melting point sealing glass 9 does not contain a crystalline substance inside, and there is a problem that it has low chemical durability and mechanical strength.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the drawbacks of the above-mentioned conventional examples, and suppresses the generation of bubbles in the glass for gap bonding to obtain a sufficient gap bonding strength. It is an object of the present invention to provide a magnetic head that can be manufactured and has excellent mechanical strength.

[0008]

The magnetic head of the present invention comprises:
A pair of first and second cores formed by forming a thin film made of a magnetic material on a first non-magnetic substrate made of crystallized glass and joining a second non-magnetic substrate made of crystallized glass on the thin film. A half-body, and the gap-bonding surfaces of the first and second core halves, on which the end faces of the thin film are exposed, on the gap forming side are butted against each other via a non-magnetic material serving as a gap spacer. In at least one of the first and second core halves has a vitreous layer containing vitreous on the surface of the first and second non-magnetic substrates on the side where the gap is formed. It is characterized in that the first and second core halves are gap-joined by the taken out glass.

The magnetic head of the present invention is characterized in that the vitreous material in the vitreous layer contains a crystalline material.

[0010]

According to the above structure, the glass for gap-bonding the first and second core halves is exuded from the vitreous layer formed on the gap-forming surface of the nonmagnetic substrate. The glass for gap bonding is not melted, the generation of bubbles during gap bonding is reduced, and sufficient gap bonding strength can be obtained.

Further, the glass for gap bonding contains a crystalline material and is excellent in chemical durability and mechanical strength.

[0012]

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 the magnetic head of this embodiment, and FIG. 2 is a view showing the medium sliding contact surface of the magnetic head. The same parts as those in FIGS. 12 and 13 are designated by the same reference numerals. I will omit the explanation.

In the figure, 11a and 11b are first and second core halves, and the first and second core halves 11a and 11b are provided with sendust and the like on the first non-magnetic substrates 121 and 121, respectively. Laminated films 3 and 3 of a ferromagnetic metal film 4 and an insulating film 5 such as SiO 2 are formed and formed, and second non-magnetic substrates 122 and 122 are bonded and fixed by sealing glasses 6 and 6 thereon. Become. A winding groove 13 is formed in the second core half body 11b. The first and second non-magnetic substrates 121 and 122
Is a ZnO—Al ₂ O ₃ —SiO ₂ system (for example, yield point 1
000 ° C.), Li ₂ O—SiO ₂ system (for example, yield point 85
0 ° C.), Li ₂ O—ZnO—SiO ₂ system (for example, yield point 900 ° C.), and the like, and have sufficient heat resistance. Further, as the sealing glass 6, a Na ₂ O—B ₂ O ₃ —SiO ₂ system (for example, a softening point 54
0 ° C.), ZnO—B ₂ O ₃ —SiO ₂ system (for example, softening point 580 ° C.), Na ₂ O—Al ₂ O ₃ —SiO ₂ system (for example,
A softening point of 650 ° C.) or the like is used.

PbO is formed on the surfaces of the non-magnetic substrates 121 and 122 forming the first core half 11a on the side of the gap formation.
—B ₂ O ₃ —SiO ₂ system (for example, yield point 430 ° C., softening point 510 ° C.), Na ₂ O—B ₂ O ₃ —SiO ₂ system (for example,
Sag 460 ° C., a softening point of _{540 ℃), ZnO-B 2} O 3 -
SiO ₂ system (for example, yield point 510 ° C., softening point 580
A glassy layer 14 containing an amorphous glassy material including a crystalline material such as (° C.) is formed. The glassy layer 1
The thickness of the inclusion region of 4 is 1 to 20 μm, and the glass concentration decreases from the surface of the surface on the gap forming side toward the inside of the substrate. The first and second core halves 11a and 11b
Is made of glass exuding the non-magnetic substrates 121 and 122 of the first core half 11a from the vitreous layer 14
By joining the non-magnetic substrates 121 and 122 of the core half body 11b, they are gap-joined and integrated.

Since the glassy layer 14 has a lower yielding point temperature as the concentration of the glass having a lower yielding point contained therein increases, the glassy layer 14 is adjusted by adjusting the concentration of the glass. The yield point temperature on the surface of the can be adjusted to an appropriate temperature, for example, 400 to 600 ° C. Therefore, the first and second core halves 11a, 11b are formed by heating the glass in the vitreous layer 14 at a temperature of 400 to 600 ° C., which is a yield point temperature lower than the softening point. The glass in 14 can be exuded to form a gap junction, and a magnetic gap 10 formed by interposing SiO ₂ or the like is formed on the junction surface. The glassy layer 1
4 has a thickness of the first and second non-magnetic substrates 121, 12
It is possible to obtain a desired value by combining 2 and the material of the vitreous layer 14 or by appropriately changing the heating and melting conditions.

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

First, as shown in FIG. 3, a laminated film 3 of a ferromagnetic metal film 4 and an insulating film 5 is deposited on the upper surface of a non-magnetic substrate 12 made of crystallized glass by sputtering or the like to form a laminated substrate 15. Form. The laminated substrate 15 is made of SiO ₂ , Ti ₂ O, ZnO or the like at a thickness of 0.1 to 0.5 on the uppermost surface of the laminated film 3 in order to improve the strength of bonding described later.
A protective film (not shown) having a thickness of μm is formed.

Next, as shown in FIG. 4, the laminated substrate 1
Prepare a plurality of 5 and stack them, each Na ₂ O-Al ₂ O
_The sealing glass 6 made of _3- SiO ₂ system is 600 to 700
By heating and melting at a temperature of ° C, they are glass-bonded and integrated to form a laminated block 16. A second non-magnetic substrate 122 is bonded and fixed to the uppermost surface of the laminated block 16.

Next, by cutting along the broken lines aa 'and bb' in FIG. 4, a pair of laminated head pieces 17a, 17b are formed as shown in FIG.

Next, as shown in FIG. 6, the non-magnetic substrate 1 on the surface on the gap forming side of one of the laminated head pieces 17a.
A groove 18 for glass filling is formed in the portion 2 so as to be adjacent to the laminated film 3.

Next, as shown in FIG. 7, the on the surface of the groove 18 is formed a gap formed side of the laminating head piece _{17a, PbO-B 2 O 3} -SiO 2 system, Na ₂ O-B ₂ O ₃
-Si0 ₂ system, or placing the glass plate made of ZnO-B ₂ O ₃ -Si0 ₂ system like glass, heating and melting the glass plates _{(e.g., Na 2 O-B 2 O} 3 -Si0 2 system If 50
The molten glass 19 is filled in the groove 18 by holding it at 0 ° C. for 1 hour, and the glass quality of the molten glass 19 is further formed on the surface (interface) of the non-magnetic substrate 12 in contact with the molten glass 19. Diffusion reaction occurs and glassy layer 1
4 is formed.

Next, as shown in FIG. 8, the portion of the non-magnetic substrate 12 where the groove 18 is formed is removed by grinding, polishing or the like so that the vitreous layer 14 remains adjacent to the laminated film 3. .

The steps of forming the glassy layer 14 shown in FIGS. 7 and 8 are shown in FIG. FIG. 11 (a)
1 is a diagram showing a state just before placing the glass plate 191; FIG.
1 (b) is a diagram showing a state where the groove 18 is filled with glass, and FIG. 11 (c) is a diagram showing the vitreous layer 14 in each of the grinding and polishing steps. As shown in FIG. 11A, the vitreous layer 14 is formed so that the glass concentration continuously decreases from the surface of the non-magnetic substrate 12 toward the inside of the substrate, and the layer thickness is 1 to 20 μm. Is.

Next, as shown in FIG. 9, a winding groove 13 is formed on the surface of the other laminated head piece 17b on the side where the gap is formed, and further a non-magnetic layer (not shown) such as SiO ₂ to serve as a gap spacer (not shown). Temperature) near the sag point of the glass forming the vitreous layer 14 in a state where the surfaces on the gap forming side of the laminated head piece 17b and the laminated head piece 17a shown in FIG. (400-
The laminated head piece 17a is heated and pressed at 600 ° C. (pressurized 2 kg / cm 2, held for about 1 hour) to allow the glass material exuding from the glass material layer 14 to absorb the laminated head piece 17a,
Layered head block 20 by gap bonding 17b
To form.

After that, the laminated head block 20 is cut along a broken line cc 'shown in FIG. 10 to form a plurality of laminated head chips, and the laminated head chips are subjected to a predetermined shape processing. The laminated core type magnetic head of this embodiment shown in FIG. 1 is completed. By the cutting step, the nonmagnetic substrate 12 is divided into the first nonmagnetic substrate 121 and the second nonmagnetic substrate 122.

In the magnetic head of this embodiment as described above,
The first and second core halves 11a and 11b are composed of the vitreous layer 14
By heating in the vicinity of the yield point temperature lower than the softening point of the vitreous material inside, the non-magnetic substrate 12 of the first core half body 11a
Since the gap bonding is performed by the glass exuding from the vitreous layer 14 formed on the surface on the gap forming side of Nos. 1 and 122, it is unlikely that the glass for gap bonding melts at a temperature higher than its softening point as in the conventional case. There is almost no generation of bubbles due to dirt on the joint surface. Moreover, the glass for gap bonding, which exudes from the vitreous layer 14, contains a crystalline substance and is excellent in chemical durability and mechanical strength. Further, since the vitreous material in the vitreous layer 14 is based on crystallized glass as in the non-magnetic substrate, the vitreous layer 14 is made into the non-magnetic substrate 121, 1.
Even if it is exposed to the medium sliding contact surface 22, uneven wear does not occur in the exposed portion. Therefore, the vitreous layer 14 can be formed close to the magnetic gap 10, the area of the glass bonding portion in the gap bonding can be increased, and the gap bonding strength can be increased.

[0028]

According to the present invention, a magnetic head having excellent mechanical strength and high reliability can be provided by firmly gap-bonding the first and second core halves.

[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 method of manufacturing the magnetic head of the present invention.

FIG. 9 is a perspective view showing the method of manufacturing the magnetic head of the present invention.

FIG. 10 is a perspective view showing the method of manufacturing the magnetic head of the present invention.

FIG. 11 is a diagram showing a step of forming a glassy layer of the magnetic head of the present invention.

FIG. 12 is a perspective view showing the appearance of a conventional magnetic head.

FIG. 13 is a diagram showing a medium sliding contact surface of a conventional magnetic head.

[Explanation of sign]

 3 Laminated film (thin film made of magnetic material) 10 Magnetic gap 11a First core half body 11b Second core half body 121 First non-magnetic substrate 122 Second non-magnetic substrate 14 Vitreous layer

Claims (2)

[Claims] 1. A pair of a first non-magnetic substrate made of crystallized glass, a thin film made of a magnetic material formed on the first non-magnetic substrate, and a second non-magnetic substrate made of crystallized glass bonded on the thin film. Gap between the first and second core halves, the surfaces of the first and second core halves on the gap forming side where the end faces of the thin film are exposed are abutted via a non-magnetic material serving as a gap spacer. In a bonded magnetic head, at least one of the first and second core halves has a vitreous layer containing vitreous on the gap-forming surface of the first and second non-magnetic substrates, A magnetic head characterized in that the first and second core halves are gap-joined by glass exuding from the vitreous layer. 2. The magnetic head according to claim 1, wherein the vitreous material in the vitreous layer contains a crystalline material.