JPH04324105A - Production of magnetic head - Google Patents

Abstract

PURPOSE:To suppress the splashing of magnetic head chips and to decrease failures as the individual magnetic head chips are secured by a soluble adhesive in spite of grinding of the part remaining without being cut, thereby eventually improving the production yield of the magnetic head. CONSTITUTION:Grooves 12 which have a prescribed depth and do not reach a side face 11 are formed from one side of a flank 10 of a core block 9 toward the flank 11 and the soluble adhesive is packed into these grooves 12. The part 13 remaining without being cut by the working of the grooves 12 is thereafter ground and the soluble adhesive is removed, by which the core block is separated to the individual magnetic head chips 14.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a magnetic head having a high saturation magnetic flux density necessary for high-density recording and reproduction in video tape recorders and the like.

0002

[Background Art] In recent years, with the increase in the density of magnetic recording media,
High coercive force media such as metal tapes are becoming mainstream. For this reason, core materials used in magnetic heads are also required to have a high saturation magnetic flux density. Therefore,
For example, as shown in FIG. 10, a magnetic head chip 21 is used in which a soft magnetic thin film 23 having a high saturation magnetic flux density is provided on a substrate 22.

In the above magnetic head, a non-magnetic material such as crystallized glass or ceramics is selected for the substrate 22 in consideration of wear resistance and alpha matching with the soft magnetic thin film. A soft magnetic thin film 23 made of sendust or the like is formed on one inclined surface of the substrate 22, and the pair of substrates 22 are welded and bonded to each other using a low melting point glass 24. At this stage, a core block having a generally rod-like overall shape is formed by the mutually bonded substrates 22 and 22, and this core block is cut at predetermined intervals in the length direction (hereinafter referred to as By slicing process),
A magnetic head chip 21 shown in FIG. 10 is manufactured. Conventionally, such slicing processing is performed as shown in FIG.
This is done by adhesively fixing the core block 25 onto the dummy plate 26 and forming a separation groove extending from the upper surface to the dummy plate 26 side, for example, by dicing using a rotating blade.

0004

However, in the conventional slicing process as described above, a problem arises in that the separated magnetic head chips are easily scattered and damaged. That is, in the above-mentioned slicing process, cutting is performed with a large processing force because the substrate material is difficult to process as described above. During this time, the core block 25 is adhesively fixed on the dummy plate 26, but the adhesive fixing force on the core block 25 side no longer acts on the magnetic head chip 21 that is separated from the core block 25 side. , the fixing force decreases to a state corresponding to the adhesive area of the magnetic head chip 21 alone. Therefore, immediately after the machining groove reaches the dummy plate 26 side, a machining load that exceeds the fixing force acts, and as a result, the magnetic head chip 21 that has been separated
This may cause scattering or damage.

[0005]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the method for manufacturing a magnetic head of the present invention includes core blocks formed in a substantially rod shape, which are arranged so as to intersect with each other in the longitudinal direction and at predetermined intervals. In a method for manufacturing a magnetic head, the method includes the step of manufacturing magnetic head chips by separating them individually along parallel separation planes, from one side to an intermediate position along the separation plane toward the other. After performing a first separation process of cutting, then filling a soluble adhesive into the groove created by this first separation process, and then performing a second separation process of penetrating the tip of the groove to the other side. , the soluble adhesive is dissolved and removed to separate the magnetic head chips into individual magnetic head chips.

[0006]

[Operation] According to the above method, first, the first separation process is carried out while maintaining the state in which the core blocks are continuous in the length direction. Therefore, during this time, the fixing force of the core block remains applied to the entire core block, and the machining load does not exceed the fixing force in the machining area. Furthermore, while the second separation process is being performed, the core blocks are kept connected in the length direction via the soluble adhesive, so that the process load does not exceed the fixing force during this time as well. Does not occur. Separation into individual magnetic head chips occurs only at the stage of dissolving and removing the above-mentioned soluble adhesive, and no processing force is applied at this stage. This makes it possible to separate the magnetic head chips into individual magnetic head chips without causing scattering or damage.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail with reference to FIGS. 1 to 8 in order to explain the manufacturing process of a magnetic head.

First, as shown in FIG. 2, a plurality of substantially V-shaped cross sections having predetermined dimensions and depth are formed on the surface of a substantially rectangular parallelepiped substrate 1 made of a nonmagnetic material such as crystallized glass or ceramics. Grooves 2 are formed adjacent to each other at a predetermined pitch dimension A and extending parallel to each other. Although the substrate 1 has excellent wear resistance, it is difficult to process the grooves 2. For example, the grooves 2 are processed using a rotating blade having a grinding surface with a substantially V-shaped cross section in accordance with the shape of the grooves 2. This is done through processing.

Next, as shown in FIG. 3, each of the grooves 2...
A soft magnetic thin film 3 made of, for example, sendust or the like is formed with a predetermined thickness on one of the inclined surfaces by vacuum evaporation, sputtering, or the like. Next, as shown in FIG. 4, low melting point glass 4 is filled so as to fill each groove 2 from the surface, and then, as shown in FIG. The surface of the glass 4 is polished into a flat surface.

Next, as shown in FIG. 6, a coil winding window 5 and a coil winding groove 6 are formed on the substrate 1, and further,
A non-magnetic gap material such as SiO2 is deposited on the polished surface by vacuum evaporation or sputtering to form a gap surface 7, and a one-sided core block 8 is fabricated.

After this, as shown in FIG. 7, the pair of one-sided core blocks 8, 8 have their respective gap surfaces 7, 7 facing each other, and their respective soft magnetic thin films 3, 3 are positioned on the same straight line. The substantially rod-shaped core block 9 is produced by joining in this state.

Next, the core block 9 is cut along a plane perpendicular to its length. In the core block 9, soft magnetic thin films 3 inclined with respect to the center line are sequentially exposed on the upper surface in the figure, and the plane passing through each end position of each soft magnetic thin film 3 is the separation plane, and therefore, The above cutting operation is performed along each separation plane at intervals B as shown. In this operation, as shown in FIG.
from the side surface (the upper surface in the figure) 10 facing the magnetic head to a depth that somewhat exceeds the predetermined width dimension of the magnetic head.
First, a first separation process is performed to form cutting grooves 12 along each separation surface. This processing is performed, for example, by dicing using a conventional rotating blade.

After that, a soluble adhesive (
(not shown) is filled. After separating from the dummy board, the uncut portion 1 on the side surface 11 side in the first separation process is
A second separation process is performed for No. 3. This processing is performed by grinding in the direction of the arrow from the side surface 11 to the position indicated by the broken line in the figure. As a result, the uncut portion 1
3 is removed, and each cutting groove 12 in the first separation process becomes a penetrating state where it is exposed on the side surface 11 side. Note that during this time, the entire core block 9 is held in an integrally connected state with the above-mentioned soluble adhesive.

[0014] After completing the above processing, the soluble adhesive is dissolved and removed. As a result, the magnetic head chips 14 are individually separated at the positions of the cutting grooves 12 and have the shape shown in FIG.
...is produced.

The magnetic head chip 14 then has the following steps:
A coil winding 15 is applied, fixing to a base plate (not shown), tape sliding surface polishing, etc. are performed, and the magnetic head is completed.

As explained above, in the process of cutting the core blocks 9 to form individual magnetic head chips 14, the core blocks 9 are maintained in a continuous state in the length direction. Then, a first separation process is performed, and then a second separation process is performed while maintaining the longitudinally connected state via a soluble adhesive as described above.

[0017] Therefore, during these separation processes, the entire core block 9 is maintained in a state where a fixing force is applied, and a state in which the processing load exceeds the fixing force in the processing area does not occur. Separation into individual magnetic head chips 14 occurs only at the stage of dissolving and removing the above-mentioned soluble adhesive, and no processing force is applied at this stage. This makes it possible to separate the magnetic head chips 14 into individual magnetic head chips 14 without causing scattering or damage. As a result, the manufacturing yield of magnetic heads can be improved.

In the above embodiment, the second separation process is performed by grinding, but the uncut portion 1
It is also possible to use other processing methods such as forming cutting grooves by dicing or the like in accordance with each separation surface from the side surface 11 on the third side to the tip of the cutting groove 12 in the first separation process.

[0019]

Effects of the Invention As described above, the method for manufacturing a magnetic head of the present invention includes the first step of cutting a core block, which is formed into a substantially rod shape, along the separation surface from one surface to an intermediate position toward the other surface. After performing a separation process, filling the grooves created in the first separation process with a soluble adhesive, and then performing a second separation process in which the tips of the grooves penetrate through to the other side,
The soluble adhesive is dissolved and removed to separate the magnetic head chips into individual magnetic head chips.

[0020] Thereby, final separation into individual magnetic head chips is performed by dissolving and removing the soluble adhesive without the need to apply processing force. For this reason, it is possible to separate the magnetic head chips into individual magnetic head chips without causing scattering or damage, resulting in an effect that the manufacturing yield of the magnetic head can be improved.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a core block at the end of a first separation process in a method for manufacturing a magnetic head according to an embodiment of the present invention.

FIG. 2 is a perspective view of a substrate on which grooves are formed in the method for manufacturing the magnetic head.

FIG. 3 is a front view of a substrate in which a soft magnetic thin film is formed in the groove.

FIG. 4 is a front view of a substrate in which the grooves are filled with low melting point glass.

FIG. 5 is a front view of a substrate on which the low melting point glass is polished into a flat shape.

FIG. 6 is a perspective view of a one-sided core block in which a coil winding groove is formed in the substrate and a gap material is further provided.

FIG. 7 is a perspective view of a core block produced by joining a pair of one-sided core blocks facing each other.

FIG. 8 is a perspective view of a magnetic head chip obtained by slicing the core block at a predetermined pitch.

FIG. 9 is a perspective view of a core block showing a slicing step in a conventional magnetic head manufacturing method.

FIG. 10 is a perspective view of a magnetic head chip cut out through the slicing process.

[Explanation of symbols]

1　　　　Substrate 3 Soft magnetic thin film 9 Core block 10/11 Side 12 Groove 13 Uncut part 14 Magnetic head chip

Claims (1)

[Claims] 1. A step of manufacturing a magnetic head chip by separating core blocks each having a substantially rod shape into individual parts along separation planes that intersect with each other in the longitudinal direction of the core blocks and are parallel to each other at predetermined intervals. In the method for manufacturing a magnetic head, a first separation process is performed to cut along the separation plane from one surface to a midway point toward the other surface, and then a soluble A second groove is filled with adhesive and then penetrates the tip of the groove to the other side.
A method for manufacturing a magnetic head, which comprises performing separation processing and then dissolving and removing a soluble adhesive to separate the magnetic head chips into individual magnetic head chips.