JPH04285706A - Magnetic head and production of it - Google Patents

Abstract

PURPOSE:To prevent the degradation of the electromagnetic conversion characteristics in a short wavelength region, to greatly improve the defects of the frequency characteristics and to supply the magnetic head of a high yield by forming a high-definition gap length by preventing the corrosion of a boundary part between a winding wire pore slanting surface of a first magnetic block and a gap forming part in the magnetic head used for various information devices. CONSTITUTION:The magnetic head is provided with a first magnetic head block 1 forming the winding wire pore 2, a second magnetic block 5 and a glass material 6 stucked the prescribed first magnetic block 1 and the prescribed second magnetic block 5 with a gap material 8. It has a constitution on which a non-magnetic film consisting of an oxidized non-magnetic material or a high melting point metal non-magnetic material is formed on the winding wire pore slanting surface 3 provided at the gap side of the prescribed first magnetic block 1.

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 video tape recorders, electronic calculators, etc., and a method for manufacturing the same.

0002

[Background Art] In recent years, technological developments have been actively carried out to make magnetic disk drives for electronic computers, etc. smaller and to increase their capacity.
In magnetic recording media, higher coercivity (Hc) and thinner films have been developed, while magnetic heads have a high saturation magnetic flux density (B
A so-called metal-in-gap type magnetic head has been developed in which the vicinity of the magnetic gap is formed of a metal magnetic material such as a Fe-Al-Si alloy or an amorphous alloy having the following characteristics. In addition, narrowing the track width is being researched in order to improve the recording density in the track width direction, but gap depth (G.D) and gap length (G. L) is required to be highly accurate.

A conventional magnetic head and its manufacturing method will be explained below. FIG. 3 is a front view of a conventional magnetic head, FIG. 4 is an enlarged view of part A in FIG. be. 1 is a first made of Mn-Zn ferrite, etc.
A magnetic block, 2 is a winding hole formed by grinding with a diamond grindstone or the like on the side surface of the first magnetic block 1, 3 is a mirror-finished winding hole slope, 4 is a gap forming part, and 5 is the first magnetic block 1. A second magnetic block made of the same material, 6
7 is a glass material for adhesion, and 7 is a boundary between the winding hole slope 3 and the gap forming portion 4. In FIG. 5, 21 is a window for forming a winding hole and a closed magnetic path, 22 is an inner edge of the window 21 for forming a winding hole and a closed magnetic path, and 23 is a non-reducing substance for bonding.

A method of manufacturing the conventional magnetic head constructed as described above will be described below with reference to FIGS. 3 and 5. The magnetic head of the type shown in FIG. 3 has a first magnetic block 1.
After forming a winding hole 2 using a diamond grindstone or the like, the winding hole slope 3 is finished to a mirror surface. Next, after processing the gap forming part 4 of the first magnetic block 1 and the second magnetic block 5 into a mirror surface, the first magnetic block 11 and the second magnetic block 5 are connected through a gap material made of a non-magnetic material such as SiO2. They are made to face each other, and then a glass material 6 for adhesion is attached, and the glass material 6 is melted and bonded at a high temperature of about 700° C. to manufacture them.

The magnetic head of the type shown in FIG. 5 is manufactured by attaching a non-reducing substance 23 to the inner edge 22 of the winding hole/closed magnetic path forming window 21 before the core halves 1 and 5 are butted and joined. .

[0006]

However, in the above-mentioned conventional structure, in the magnetic head shown in FIG.
The n-ferrite is eroded and the winding hole slope 3 and gap forming part 4 are formed.
There was a problem in that the boundary 7 formed by the gap became unclear, and the gap length further increased by about 3 μm from the boundary 7, as shown by the dotted line in FIG. In particular, recent magnetic heads
In order to obtain high output with narrow tracks, the gap depth is processed to be extremely short, for example, around 5 μm. However, due to variations, magnetic heads processed to have a gap depth of 3 μm or less have too large a gap length and cannot be used as products. However, there was a problem in that the yield was significantly lowered. Furthermore, as the gap depth becomes smaller and the gap length becomes more precise due to higher density recording in the future, there is a problem that the product yield will further decrease.

Furthermore, in the magnetic head shown in FIG.
Since a non-reducing substance 23 is attached to the inner edge 22 of the magnetic block 5, when bonding the first magnetic block 1 and the second magnetic block 5, even if there is a vertical misalignment of only a few microns, the gap length will increase. Since the width of the gap becomes wider, there is a problem in that it is impossible to manufacture a magnetic head that requires precision in gap length.

The present invention solves the above conventional problems, and provides a magnetic head and its magnetic head which prevent erosion of the boundary between the winding hole slope of the first magnetic block and the gap forming part and have a highly accurate gap length. The purpose is to provide a manufacturing method.

[0009]

[Means for Solving the Problems] In order to achieve this object, the magnetic head of the present invention has a structure in which a non-magnetic film is formed on the slope of the winding hole of a first magnetic block in which the winding hole is formed. In addition, the method for manufacturing a magnetic head includes forming a winding hole in a first magnetic block, then forming a nonmagnetic film on the slope of the winding hole, and then forming a gap forming part between the first magnetic block and the second magnetic block. is mirror-finished, then a film of gap material is formed on the gap forming parts, each gap forming part is made to face each other, a glass material for adhesion is attached, and the glass material is melted at high temperature to manufacture a magnetic head. It has a structure consisting of steps.

0010

[Operation] With this configuration, the magnetic head can be operated under high temperature heating because the glass material and the Mn-Zn ferrite, which is the material of the first magnetic block, do not come into direct contact due to the presence of the non-magnetic film formed on the slope of the winding hole. Also, erosion of the Mn-Zn ferrite can be prevented, and as a result, high accuracy of the gap length can be achieved and the shortest gap depth can be obtained.

[0011]

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

FIG. 1 is a front view of a magnetic head in one embodiment of the present invention, and FIG. 2 is an enlarged view of section A in FIG.

1 is a first magnetic block, 2 is a winding hole, 3 is a slope of the winding hole, 4 is a gap forming part, 5 is a second magnetic block, and 6 is a glass material for bonding, and these are the conventional examples. Since it is similar to the above, the same number will be given and the explanation will be omitted. 8 is a gap material, 9 is a nonmagnetic film formed by a thin film forming method such as a sputtering method, and 10 is a metal magnetic film made of a Fe-Al-Si alloy or the like.

Here, as the nonmagnetic film 9, an oxide nonmagnetic material such as SiO2 or Al2O3 or a high melting point metal nonmagnetic material such as Ti or Cr is used. SiO2 and Al2O3
Non-magnetic oxide materials such as the above are preferable because they have good compatibility with the glass material 6 for adhesion and there is no risk of peeling or the like. When using an oxide nonmagnetic material such as SiO2 or Al2O3, the thickness of the nonmagnetic film 9 is equal to or greater than the gap length, preferably 1.
A thickness of 0 μm or more is desirable. This is to prevent erosion of the glass material 6 for adhesion. When using a high melting point nonmagnetic material such as Cr, Ti or an alloy thereof, the thickness is preferably 0.1 μm or more. This is because these materials are hardly eroded by the glass material 6 for adhesion, so even if they are thin, erosion of the core material such as Mn-Zn ferrite can be prevented.Furthermore, metal materials are generally used in the vacuum thin film forming process in a short time. It has the advantage of being able to be formed into a film, and although the cost is somewhat high, the non-magnetic film 9 can be made thinner, so it is possible to significantly improve productivity and workability.

Since the metal magnetic film 10 has a flat surface where the second magnetic block 5 contacts the glass material 6 for adhesion without a boundary like the first magnetic block 1, erosion by the glass material 6 for adhesion occurs. Since it is difficult to do so, it is not necessary to provide it if the magnetic head is a general-purpose product. However, in a magnetic head that records on and reproduces information from a recording medium with high coercive force (Hc), forming a metal magnetic film such as a Fe-Al-Si alloy on the gap forming surface of the second magnetic block 5 increases the recording density. It is preferable to form it because it can be used for various purposes. The metal magnetic film is M
Since the adhesive glass material 6 is much less eroded than n-Zn ferrite, there is no need to further form a nonmagnetic film on the metal magnetic film surface.

A method of manufacturing the magnetic head constructed as described above will be explained below.

After forming the winding hole 2 in the first magnetic block 1 made of Mn--Zn ferrite or the like using a diamond grindstone or the like, the winding hole slope 3 is finished to a mirror surface using a diamond grindstone or the like having a small abrasive grain diameter. Next, a film of a high melting point material such as SiO2, Ti-based alloy, or Cr-based alloy is formed on the winding hole slope 3 by a vacuum thin film forming technique such as sputtering to form a nonmagnetic film 9.

Next, the gap forming portions 4 of the first magnetic block 1 and the second magnetic block 5 are polished to a mirror surface by lapping or the like using diamond abrasive grains. The non-magnetic film 9 formed on the gap forming part 4 by this lapping process
is removed, leaving the non-magnetic film 9 only on the winding hole slope 3 where the non-magnetic film 9 is required.

Next, a gap material 8 having a size equivalent to the gap length (GL) is formed on the gap forming part 4 by vacuum thin film formation of SiO2, glass, etc. to form a gap between the first magnetic block 1 and the second magnetic block 5. The forming portions 4 are made to face each other and pressurized. After that, insert the glass material 6 for bonding into the winding hole 2 and heat it to 700℃.
The first magnetic block 1 and the second magnetic block 5 are bonded at the front and rear. Also, in the conventional magnetic head of the type shown in FIG. 3, the gap forming portion 4 of the second magnetic block 5 is as shown in FIG.
Since a non-magnetic film corresponding to the non-reducing substance 23 shown in FIG. Therefore, even if misalignment occurs between the magnetic blocks during adhesion, it is possible to prevent a defective phenomenon in which the gap length (GL) increases.

After bonding the first magnetic block 1 and the second block 5, a magnetic head is manufactured by cutting them at a desired position.

In the magnetic head manufactured by the above manufacturing method, since the non-magnetic film 9 is interposed between the winding hole slope 3 and the glass material 6, the glass material 6 maintains the Mn of the boundary portion 7 even at high temperatures of around 700°C. - Does not erode Zn ferrite.

[0022]

As described above, the present invention forms a non-magnetic film on the slope of the winding hole and prevents direct contact between the adhesive glass material and the slope of the winding hole of the first magnetic block. Even at high temperatures around ℃, the adhesive glass material prevents erosion of the boundary between the winding hole slope of the first magnetic block and the gap forming surface, allowing a highly accurate gap length (G.L) to be obtained. Even a short magnetic head with (G.D) of about 1 μm can be easily manufactured. Furthermore, since the gap length (GL) does not widen, it is possible to prevent deterioration of electromagnetic conversion characteristics in the short wavelength range, significantly improve frequency characteristic defects, and significantly improve product yield. An excellent magnetic head and method for manufacturing the same can be realized.

[Brief explanation of the drawing]

FIG. 1 is a front view of a magnetic head in an embodiment of the present invention.

[Figure 2] Enlarged view of section A in Figure 1

[Figure 3] Front view of a conventional magnetic head

[Figure 4] Enlarged view of part A in Figure 3

[Fig. 5] Perspective view of another conventional example

[Explanation of symbols]

1 First magnetic block 2 Winding hole 3 Winding hole slope 4 Gap forming part 5 Second magnetic block 6 Glass material 7 Boundary part 8 Gap material 9 Non-magnetic film 10 Metal magnetic film

Claims (3)

[Claims] 1. A first magnetic block having a winding hole formed therein, a second magnetic block, and a glass material bonding the first magnetic block and the second magnetic block through a gap material.
1. A magnetic head comprising: a non-magnetic film formed on a slope of a winding hole provided on the gap side of the first magnetic block. 2. The magnetic head according to claim 1, wherein the nonmagnetic film is made of an oxide nonmagnetic material or a high melting point metal nonmagnetic material. 3. A step of forming a winding hole of a first magnetic block, a step of forming a nonmagnetic film in the winding hole, and a step of forming a winding hole of the first magnetic block.
A step of mirror-finishing the gap forming portions of the magnetic block and the second magnetic block, a step of forming a film of gap material on the gap forming portion, and a step of making each of the gap forming portions face each other and melt-bonding them with a glass material for bonding. A method of manufacturing a magnetic head, comprising: