JPH05334618A - Magnetic head and its prodcution - Google Patents

Abstract

PURPOSE:To provide the magnetic head with which a narrow track width is obtainable with good accuracy without impairing the contact characteristic with a recording medium. CONSTITUTION:The magnetic head 20 has a head core 21 constituted of a pair of base bodies 21a and magnetic metallic films 24a, 24b are inserted between the respective base bodies 21a. The respective butt parts of the magnetic metallic films 24a, 24b form the track width regulating parts corresponding to the track of the recording medium cooperatively with each other and the width size Tw of the track width regulating parts is so regulated by a pair of track width regulating grooves 26 as to be equal to the prescribed track width. The respective track width regulating grooves are formed on the sliding face 21b. The cross sectional shape of the respective track width regulating grooves 26 is rectangular and the width size of the respective track width regulating grooves 26 is W. The depth size D thereof is larger than a gap depth d.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a hard disk device,
The present invention relates to a magnetic head used in a magnetic recording device such as a floppy disk device and a VTR, and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, a magnetic recording device having a large storage capacity has appeared with an increase in the amount of information to be processed, and this magnetic recording device has a magnetic property having a high coercive force Hc in order to increase the storage capacity. A high-density recording medium made of material is used.

However, in the ferrite magnetic head, since the material of the head core constituting the main body is a ferrite material, the saturation magnetic flux density is relatively small and a sufficient write magnetic field strength can be obtained for the high density recording medium. Can't
It cannot be used in a magnetic recording device equipped with a high-density recording medium. Further, since the track width is regulated by the groove processing of the track width regulating groove, it is difficult to further narrow the track width by the groove processing. Therefore, instead of the ferrite magnetic head, a composite type head is used as a magnetic head for a high density recording medium.

This composite type head, as shown in FIG.
The head core 1 is composed of a pair of bases 1a facing each other and having a sliding surface 1b with a recording medium.
Each base 1a is made of a ferrite material. A winding groove 2 extending parallel to the sliding surface 1b is formed on one side of the base body 1a.

The head core 1 is formed with a pair of track width regulating grooves 3 facing each other. Each track width regulation groove 3 is arranged between one side and the other side of the base body 1a so as to be orthogonal to the winding groove 2. The track width regulation groove 3 has a substantially triangular cross-sectional shape.
Is filled with a glass material 7 for joining one side and the other side of the base body 1a. The angle θ of the side portion of the track width regulation groove 3 is set within the range of 30 degrees to 60 degrees.

A metal magnetic film 4 having a high saturation magnetic flux density is formed on the facing surface of each substrate 1a by a thin film forming means such as sputtering. The thickness S of the metal magnetic film 4 is
The size is set within the range of several μm to several tens of μm. The portions of the metal magnetic film 4 sandwiched by the track width regulating grooves 3 are butted against each other, and a gap 5 is formed between each of them. Each of the abutting portions of the metal magnetic film 4 cooperates with each other to form a track width defining portion corresponding to the track of the recording medium, and the width dimension Tw of the track width defining portion is predetermined by the pair of track width regulating grooves 3. It is regulated to be equal to the track width.

When the above composite magnetic head is used for a recording medium having a track pitch of P, a track width of T, and a guard band of ΔT, as shown in FIG.
The thickness dimension S of the metal magnetic film 4 is in the range of 2 to 10 μm, P is in the range of 10 to 20 μm, T is substantially equal to P, ΔT is 0. Is set to. In the floppy disk device, P is 5
T is 20 to 50 so that it is in the range of 0 to 100 μm.
It is set such that ΔT falls within the range of 30 μm, ΔT falls within the range of 30 to 50 μm, and S falls within the range of 1 to 5 μm. In the hard disk device, P is 20
T is 10 to 20 μm so that it falls within the range of ˜50 μm
, ΔT is in the range of 10 to 30 μm, and S is in the range of 1 to 10 μm.

Further, in order to cope with a magnetic recording medium having a higher density, a system in which P is 5 μm, T is 10 μm, ΔT is 5 μm, and S is in the range of 1 to 10 μm has been studied. In order to set such a narrow track width, high precision is required for groove processing for regulating the track width of the metal magnetic film. However, from the track positioning accuracy, track pitch, guard band, etc., an accuracy of ± 1 μm or less is required for the groove processing, and it is difficult to maintain this accuracy during mass production. Therefore, if the accuracy of the groove processing is lowered, the C / N ratio is deteriorated by the crosstalk signal from the adjacent track.

For example, referring to FIG. 11, a grindstone 8 having a tip angle of (180 ° -2θ) is used for the groove processing, the vertical variation of the mechanical precision is ΔZ, and the track width Tw is If the amount of change is ΔTw, the amount of change in the vertical direction Δ
The relationship between Z and the change amount ΔTw of the track width Tw satisfies the following expression (1).

[0010]

ΔTw = 2 × ΔZ / (tan θ) (1) Therefore, if θ = 45 ° and ΔZ = 1 μm, ΔTw =
It becomes 2 μm, and it is difficult to maintain the accuracy of ± 1 μm.

On the other hand, when the bottom portion 3a of the track width regulating groove 3 for regulating the track width of the metal magnetic film is perpendicular to the facing surface of the gap 5, as shown in FIG.
The track width does not change with respect to the change in the direction, and it is easy to maintain the accuracy with respect to the track width. The end of the part that defines the track width of is rounded. This rounded portion crosses over the guard band between tracks and is applied to the adjacent tracks, resulting in increased crosstalk.

On the other hand, in the composite type magnetic head used in the hard disk device, as shown in FIGS. 13 and 14, a head core 11 is embedded in a slider 10, and the head core 11 is bonded to the slider 10 with a low melting point glass material 12. There is. The track width of the metal magnetic film 13 sandwiched between the head cores 11 is regulated by cutting a part of the head core 11 as shown in FIG. Is narrow, the mechanical strength is weak, and the contact property due to the small contact area with the recording medium becomes unstable. Therefore, as shown in FIG.
And the head core 11 need to be joined.

[0013]

As described above, in the conventional composite magnetic head, it is difficult to obtain a narrow track width with high precision without impairing the contact property with the recording medium.

In order to solve the above problems, it is an object of the present invention to provide a magnetic head capable of obtaining a narrow track width with high accuracy without impairing the contact property with a recording medium, and a manufacturing method thereof. ..

[0015]

A magnetic head according to a first aspect of the present invention comprises a pair of bases facing each other, and has a dimension deeper than a side portion and a gap depth perpendicular to a sliding surface with respect to a recording medium. A head core provided with a track width regulating groove; and a magnetic film sandwiched between the bases of the head core and having a track width defining portion regulated by the track width regulating groove to be equal to a predetermined track width. ..

A method of manufacturing a magnetic head according to claim 2 is
A step of forming a magnetic film on at least one of the pair of substrates by a thin film forming means such as sputtering, and a joining block is formed by joining one and the other of the substrates so that the magnetic film is arranged therebetween. And a track width regulating groove having a dimension deeper than a side portion and a gap depth perpendicular to the surface defining the sliding surface of the joint block with the recording medium, and the track width regulating groove is formed. And a step of setting a track width defining portion of the magnetic film.

[0017]

According to a first aspect of the present invention, in the magnetic head according to the first aspect, as a groove for restricting a track width defining portion of the magnetic film to be equal to a predetermined track width, a side portion and a gap perpendicular to a sliding surface with a recording medium are provided. A track width regulating groove having a dimension deeper than the depth is formed on the sliding surface with respect to the recording medium.

Since the track width regulating groove has a dimension deeper than the side portion and the gap depth perpendicular to the surface defining the sliding surface with respect to the recording medium, the track width regulating groove is formed with high accuracy, and the track width regulating groove is formed. The track width defining portion regulated by the formation of the width regulation groove can be accurately formed so as to be equal to a predetermined track width, and thus a narrow track width can be accurately obtained. Further, by reducing the width of the track width regulating groove, it is possible to prevent the contact property between the recording medium and the sliding surface from being impaired.

In the method of manufacturing a magnetic head according to a second aspect of the present invention, after forming a joining block in which a magnetic film is sandwiched between the bases, the track width regulating groove is formed on a surface defining a sliding surface of the joining block. By forming
It is possible to obtain a magnetic head in which the contact property with the recording medium is not impaired and the narrow track width is formed with high accuracy.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing an embodiment of the magnetic head of the present invention, FIG. 2 is an enlarged plan view showing the periphery of the gap of the magnetic head of FIG. 1, and FIG. 3 is a line AA of FIG. It is sectional drawing obtained along with.

As shown in FIGS. 1 to 3, the magnetic head 20 is composed of a pair of bases 21a opposed to each other, and a head core 21 on which a sliding surface 21b with a recording medium is formed.
Equipped with. Each base 21a is made of a ferrite material. A winding groove 22 extending parallel to the sliding surface 21b is formed on one side of the base body 21a.

The head core 21 is formed with a pair of track width regulating grooves 23 facing each other. Each track width regulation groove 23 is formed in the base 2 so as to be orthogonal to the winding groove 22.
It is arranged between one side and the other side of 1a. Each track width regulation groove 23 is filled with a glass material 27 for joining one side and the other side of the base body 21a.

Metal magnetic films 24a and 24b having a high saturation magnetic flux density are sandwiched between the bases 21a. The metal magnetic film 24a is formed on the facing surface of one base 21a by a thin film forming means such as sputtering, and similarly, the metal magnetic film 24b is formed on the facing surface of the other base 21a. The thickness of the metal magnetic films 24a and 24b is set within the range of several μm to several tens of μm. The portions of the metal magnetic films 24a and 24b sandwiched by the track width regulating grooves 23 are butted against each other, and a gap 25 is formed between them. The gap depth of the gap 25 is d.

The abutting portions of the metal magnetic films 24a and 24b cooperate with each other to form a track width defining portion corresponding to the track of the recording medium, and the width dimension Tw of the track width defining portion has a pair of track width regulation. The groove 26 regulates the width to be equal to a predetermined track width.

Each track width regulating groove 26 is a groove extending parallel to each other and extending from one side of the base 21a to the other side via the metal magnetic films 24a and 24b, and the groove is the head core 21.
Is formed on the sliding surface 21b. Each track width regulation groove 26 has a rectangular cross-sectional shape. The width dimension of each track width regulation groove 26 is W, and the depth dimension D thereof is larger than the gap depth d.

In order to maintain good contact with the recording medium, it is preferable that the relationship between the track width Tw and the width dimension W of the track width regulating groove 26 satisfies the following expression (2).

[0028]

## EQU00002 ## W.ltoreq.10.Tw (2) However, the above relationship is slightly different depending on the relative speed between the recording medium and the magnetic head 20, the tension of the recording medium, and the like.

As described above, in the magnetic head 20, since the width dimension of the track width defining portion formed by the metal magnetic films 24a and 24b is regulated by the track width regulating groove 26, it is formed by the metal magnetic films 24a and 24b. The width dimension of the track width defining portion can be matched with the track width Tw with high accuracy, and a narrow track width can be obtained with high accuracy.

In this embodiment, the track width regulating groove 2
The relationship between the width dimension W of 6 and the track width Tw is as described in (2) above.
Although it is set so as to satisfy the equation, if the equation is not satisfied, the contact property with a flexible magnetic recording medium such as a magnetic tape or a floppy disk may be lowered. In order to prevent the deterioration of the contact property with the recording medium, it is preferable to fill the track width regulating groove 26 with a glass material 28 as shown in FIG. Further, a magnetic head in which the track width regulation groove 26 is filled with the glass material 28 can be used in a hard disk device. By using this magnetic head, it is not necessary to use a glass material for embedding the head core in the slider, and an organic adhesive can be used for fixing the head core and the slider.

In this embodiment, the composite type magnetic head provided with the metal magnetic film has been described as an example. However, the method of regulating the track width by the track width regulating groove 26 is a ferrite magnetic head or metal. The present invention can be applied to an in-gap head (so-called MIG head), a so-called TSS type magnetic head in which a magnetic film interface and a gap are non-parallel.

Next, a method of manufacturing the magnetic head 20 will be described with reference to the drawings. 4 to 7 are views for explaining a method of manufacturing the magnetic head of FIG. 1, and show first to fourth steps thereof, respectively.

First, as shown in FIGS. 4 (a) and 4 (b),
A block 31 in which the winding groove 30 is formed and a block 32 are prepared.

As shown in FIG. 5A, a plurality of track width regulating grooves 33 extending at right angles to the winding groove 30 are formed in the block 31, and the track width regulating grooves 33 are spaced from each other by a predetermined distance. Are arranged in parallel. Block 31
A metal magnetic film (not shown) is formed on the surface where the groove 33 is formed by thin film forming means such as sputtering. As shown in FIG. 5B, a plurality of track width regulating grooves 34 are formed in the block 32, and the track width regulating grooves 34 are arranged in parallel with each other at a predetermined interval. Similar to the block 31, a metal magnetic film (not shown) is formed on the surface of the block 32 on which the track width regulating groove 34 is formed by thin film forming means such as sputtering.

After forming the track width regulating grooves 33 and 34 and the metal magnetic film, as shown in FIG. 6, the block 31 and the block 32 respectively have track width regulating grooves 33 and 34.
Are butted so as to face each other, and are integrally joined by a glass material (not shown). An insulating film for forming the gap 35 is sandwiched between the metal magnetic film of the block 31 and the metal magnetic film of the block 32. The insulating film is made of silicon dioxide. Each of the portions of the metal magnetic film that are butted against each other through the gap 35 cooperate with each other to form a track width defining portion corresponding to a track of the recording medium.

In the joint block 36 obtained by joining the block 31 and the block 32, as shown in FIG. 7, a plurality of tracks for adjusting the width dimension of the track width defining portion of the metal magnetic film to the track width. The track width regulation groove 37 is formed. The track width regulating grooves 37 are parallel to each other, and the distance between one and the other of the grooves 37 that sandwich the metal magnetic film near the gap 35 is equal to a predetermined track width.

After the track width regulating groove 37 is formed, the joining block 36 is cut along a predetermined cutting line (not shown) to obtain a head base material. After subjecting the head base material to predetermined machining, the magnetic head 20 is obtained as shown in FIG.

As described above, since the width of the track width defining portion of the metal magnetic film is restricted by the formation of the track width restricting groove 37, it is possible to obtain a magnetic head having a predetermined track width with high accuracy. As a result, it is possible to obtain a magnetic head in which a narrow track width is formed with high precision to accommodate a high-density magnetic recording medium.

[0039]

As described above, according to the magnetic head of the present invention, the contact property with the recording medium is not impaired.
It is possible to obtain a narrow track width with high accuracy for a high density recording medium.

According to the method of manufacturing a magnetic head of the present invention,
It is possible to obtain a magnetic head in which the contact property with a recording medium is stable and a narrow track width is formed with high precision to accommodate a recording medium having a higher density.

[Brief description of drawings]

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

FIG. 2 is an enlarged plan view showing the periphery of the gap of the magnetic head of FIG.

FIG. 3 is a cross-sectional view taken along the line AA of FIG.

FIG. 4 is a diagram for explaining a first step of the method of manufacturing the magnetic head of FIG.

5A and 5B are views for explaining a second step of the method of manufacturing the magnetic head of FIG.

6A and 6B are views for explaining a third step of the method of manufacturing the magnetic head of FIG.

7 is a diagram for explaining a fourth step of the method of manufacturing the magnetic head of FIG. 1. FIG.

FIG. 8 is a perspective view showing another embodiment of the magnetic head of the present invention.

FIG. 9 is a perspective view showing a conventional composite magnetic head.

10 is an enlarged plan view showing the periphery of the gap of the magnetic head of FIG. 9. FIG.

FIG. 11 is a diagram for explaining a step of forming a track width regulating groove of the magnetic head of FIG.

FIG. 12 is an enlarged plan view showing the periphery of a gap of another conventional magnetic head.

FIG. 13 is a perspective view showing a magnetic head used in a conventional hard disk device.

FIG. 14 is a plan view showing a bonded state of the head core and the slider of the magnetic head of FIG.

15 is a perspective view showing a head core of the magnetic head of FIG.

[Explanation of symbols]

 20 magnetic head 21 head core 21a, 21b substrate 22, 30 winding groove 24a, 24b metal magnetic film 25 gap 26, 37 track width regulating groove 28 glass material 31, 32 substrate 36 joint block

Claims (2)

[Claims] 1. A head core comprising a pair of bases facing each other, and a track width regulating groove having a dimension deeper than a side portion and a gap depth perpendicular to the pair, formed on a sliding surface with respect to a recording medium, and the head core. And a magnetic film having a track width defining portion which is sandwiched between the bases and is regulated by the track width regulating groove to be equal to a predetermined track width. 2. A step of forming a magnetic film portion on at least one of a pair of bases by means of thin film forming means such as sputtering, and joining one and the other of the bases so that the magnetic film is disposed therebetween. A step of forming a junction block by forming a track width regulating groove having a dimension deeper than a side portion and a gap depth perpendicular to the side surface defining the sliding surface of the junction block with the recording medium, And a step of setting a track width defining portion of the magnetic film by forming a track width restricting groove.