JP2882299B2 - Core thin film magnetic head - Google Patents

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 an HDD, and more particularly to a magnetic head having a magnetic core made of a metal magnetic thin film, and is particularly suitable for high-density recording with a small gap depth. Core thin film magnetic head.

[0002]

2. Description of the Related Art In recent years, in the field of magnetic recording, there has been an increasing demand for higher recording densities, and higher speed data has also been required. From this point, in particular, the magnetic core is formed by using a magnetic material having a high magnetic permeability and a high saturation magnetic flux density.
A magnetic head having a small inductance has been required.

In particular, recently, a core thin film magnetic head has attracted attention as a magnetic head which can satisfy the above-mentioned performance while utilizing a conventional method of manufacturing a so-called bulk type magnetic head. Various types of core thin-film magnetic heads have been proposed in which a magnetic core is formed of a metal magnetic thin film on a non-magnetic substrate. However, from the viewpoint of reducing inductance, Japanese Patent Publication No. 6-54528 discloses a core thin-film magnetic head. Things are attracting attention. In this magnetic head, as shown in FIG. 6, a metal magnetic thin film 2, 2 is formed along a winding window 5 provided on a facing surface of a pair of nonmagnetic substrates 3, 3, and a gap material is formed by the metal magnetic thin film 2, 2. To form a core thin-film magnetic head by forming a magnetic gap 14 and integrating them with glass 4 or the like.

As shown in FIG. 7, a method of manufacturing a core thin-film magnetic head of this kind is to form winding grooves 15, 15 using a dicer or the like on opposing surfaces of a pair of non-magnetic blocks 9, 9 (a). , FeAlSi, FeTaN, FeNi
(B) to form metal magnetic thin films 2 and 2 such as
The rods 40 made of glass or the like are placed in the winding grooves 15 with the
Are inserted in a welding furnace, the two are bonded and integrated (c), and sliced by a slicer to form a core thin-film magnetic head 8 (d). This integration step (c)
In the above, the gap depth end portion 11 was integrated so as not to shift as much as possible. If this portion is shifted, extra inductance is generated.

Recently, there has been a great tendency to reduce the area of the metal magnetic thin film exposed on the medium sliding surface as a whole. As shown in FIG. 8, the purpose is to reduce the magnetization transition region of the recording magnetization of the medium. The area T exposed to the medium sliding surface of the metal magnetic thin film 22 on the medium exit side with respect to the magnetic head, ie, the trailing side, for the purpose of increasing the recording magnetic field of the magnetic head.
Is made smaller than the area U exposed on the medium sliding surface of the metal magnetic thin film 23 on the medium entrance side of the magnetic head, that is, on the leading side. The reason for this is that the writing to the medium of the magnetic core is determined by the metal magnetic thin film 22 on the trailing side, and the exposed area of the metal magnetic thin film to the medium is reduced to reduce the magnetic flux. This is for increasing the perpendicular component of the recording magnetic field. As such a magnetic head, for example, Japanese Unexamined Patent Publication No.
There is one as described in 193307.

[0006]

In the above-mentioned core thin-film magnetic head, the necessity of reducing the gap depth has increased due to the recent trend of magnetic recording technology. However, the recording / reproducing characteristics of the core thin-film magnetic head having a small gap depth have been improved. The problem of inadequacy has surfaced. For example, in recent magnetic heads, those having a gap depth of 4 μm or less, particularly those having a gap depth of 1 μm or less for use in hard disk drives, have been manufactured.

As a result, even if a material with the highest saturation magnetic flux density known at present is used, a core thin film magnetic head having a small gap depth has a large head component, particularly a perpendicular component of a magnetic field of magnetic recording. In particular, magnetic saturation has become remarkable in the metal magnetic thin film portion of the magnetic core on the trailing side where the medium sliding area is small. This is because the volume of the metal magnetic thin film in this portion is too small. This greatly impairs the recording / reproducing ability of the magnetic head, especially the recording ability, and hinders the increase in recording density.

[0008]

According to the present invention, there is provided a core thin film magnetic head comprising a pair of non-magnetic substrates and a metal magnetic thin film formed on the pair of non-magnetic substrates. A winding window is formed on the opposing surfaces of the pair of non-magnetic substrates, and the metal magnetic thin film is formed on an inner peripheral surface including an apex portion of the winding window, and the apex portion of the winding window is formed. A magnetic gap is formed by sandwiching the metal magnetic thin film with the magnetic gap material sandwiched therebetween to form a magnetic gap, and the depth of the metal magnetic thin film in the gap depth direction facing the metal magnetic thin film is greater on the trailing side than on the leading side. A deeply formed, core thin film magnetic head is provided.

The core thin film magnetic head according to the present invention is characterized in that the area of the metal magnetic thin film exposed on the medium sliding surface is smaller on the trailing side than on the leading side.

Still further, the present invention provides the above-mentioned core thin-film magnetic head, wherein the contact angle of the metal magnetic thin film with the medium sliding surface is greater on the trailing side than on the leading side.

In addition, the present invention provides the above-mentioned core thin-film magnetic head, wherein a contact angle of the metal magnetic thin film forming the magnetic gap with a medium sliding surface on the trailing side is 20 to 60 degrees.

[0012]

According to the present invention, since the above structure is adopted, the area of the metal magnetic thin film exposed on the medium sliding surface is reduced as before, and the depth of the metal magnetic thin film on the trailing side of the magnetic gap portion in the gap depth direction is reduced. Therefore, magnetic saturation does not occur even when the gap depth is extremely small. Therefore, the perpendicular component of the recording magnetic field from the core thin-film magnetic head can be increased without causing magnetic saturation in the magnetic core.

The present invention also provides a volume of the metal magnetic thin film on the trailing side by making the angle of the metal magnetic thin film on the trailing side relative to the medium sliding surface larger than the angle of the metal magnetic thin film on the leading side with respect to the medium sliding surface. The effect can be realized by a very simple manufacturing method.

Further, since the angle between the metal magnetic thin film on the trailing side and the medium sliding surface is set to 20 to 60 degrees, magnetic saturation does not occur even when the gap depth is sufficiently small. The mechanical strength of the upper part of the wire window can be sufficiently secured.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. The same parts as those in the related art are denoted by the same reference numerals, and description thereof will be omitted. As shown in FIG. 1, the core thin-film magnetic head of the present invention forms a winding window 5 on a pair of non-magnetic substrates FeTaN, FeTaC, F on the inner peripheral surface of the wire window 5
eTaNCu, FeTaNC, FeMoN, FeCo
N, FeCN, FeTaNAg, FeAlSi, NiF
e, metal magnetic thin films 2 and 2 are formed by sputtering, vapor deposition, etc., a magnetic gap material is sandwiched between the metal magnetic thin films 2 and 2 to form a magnetic gap 14, and both substrates are formed using glass 4 or the like. The core thin film magnetic head 20 is formed by welding and integrating.

At this time, as shown in the enlarged view of FIG. 3, the portion of the metal magnetic thin film facing the metal magnetic thin film in the apex portion 50 forming the magnetic gap 14 is connected to the metal magnetic thin film 12 on the trailing side by the leading side. The two substrates are integrated by being slightly shifted downward from the metal magnetic thin film 13.
By doing so, the depth D in the gap depth direction on the trailing side is increased, and as a result this volume can be increased. Therefore, even if the portion S where the metal magnetic thin film on the trailing side is exposed to the medium sliding surface is small, Regardless, the trailing metal magnetic thin film 12 does not become magnetically saturated. At this time, if the gap depth of the gap depth end portion 19 is shifted by 10 to 50% with respect to the gap depth, a sufficient volume of the metal magnetic thin film that does not saturate can be secured. It should be slightly shifted.

More specifically, the method of manufacturing the core thin-film magnetic head will be described. The core thin-film magnetic head is formed by slicing a long block for mass production, and the steps are as shown in FIG. That is, the winding grooves 35, 35 are machined by a dicer or the like along the length direction of the block composed of the long non-magnetic material blocks 30, (a). Then, metal magnetic thin films 32, 32, for example, an FeTaN alloy are formed on the opposing surfaces of both blocks, and S is used as a gap material.
An iO2 or the like 33 is formed (b), the positions of both blocks are adjusted so that the winding grooves 35, 35 face each other to form a winding window, and then the glass rod 40 is fitted with the winding grooves 35, 35.
35 and placed in a welding furnace to be welded and integrated (c).

At the stage of position adjustment before entering the welding furnace, the two blocks are half-fixed to a welding jig 41 as shown in FIG. This is fixed with the tool fixing screw 46, and the micrometer 45 is fixed.
And a gap depth end portion 3 of the non-magnetic block 30, 30 by a spring 42 on the opposite side of the non-magnetic block.
1 is observed from the side with a microscope (not shown), and the trailing side is positioned below the medium sliding surface side with a displacement of about 0.2 μm. When the positioning is completed, the nonmagnetic blocks 30 are fixed with the block fixing screws 43, and a glass rod or the like (not shown) is inserted into the winding groove 47.
The welding jig 41 is put into a welding furnace (not shown) by loosening the welding jig fixing screw 46, and the two blocks are integrated by welding.

If the block integrated in this way is sliced by a slicer or the like, a plurality of core thin-film magnetic heads 20 having the same gap depth end deviation amount can be obtained at a time as shown in FIG. I can do it. As the non-magnetic substrate used in the core thin-film magnetic head, various ceramics and various glass substrates can be used.
Further, as the gap material, SiO2, Al2O3, or the like, or a laminated film of these and a certain metal material can be used.

In order to make the area of the metal magnetic thin film on the trailing side exposed on the medium sliding surface smaller than the area of the metal magnetic thin film on the leading side exposed on the medium sliding surface, in the above step (b), the tray The formed film thickness of the metal magnetic thin film on the ring side is made smaller than the formed film thickness of the metal magnetic thin film on the leading side. Specifically, for example, when the track width is 1 μm, the thickness of the metal magnetic thin film on the leading side is set to 1 μm and the thickness of the metal magnetic thin film on the trailing side is set to 0.2 to 0.5 μm.
It should just be about.

The angle formed between the metal magnetic thin film on the trailing side and the medium sliding surface of the medium may be greater than the angle formed between the metal magnetic thin film on the leading side and the medium sliding surface. The contact angle with the sliding surface is 20 ~
To increase the volume of the metal magnetic thin film on the trailing side by setting it to 60 degrees, when grooves are formed on the long blocks 30, 30 with a dicer or the like in the step (a) of FIG.
As shown in FIG. 7, the groove processing of the long block may be performed by using the diamond blade portions 37, 39 on the outer periphery of the metal support portions 36, 38 of the dicer blade having desired tip angles α, β. In this way, as shown in FIG. 2, the metal magnetic thin film formed thereon by sputtering or the like is also formed at a desired angle of α and β with the medium, that is, 20 to 60 degrees.

As described above, if the contact angle β of the metal magnetic thin film 17 on the trailing side with the medium sliding surface is made larger than the contact angle α of the metal magnetic thin film 18 on the leading side with the medium sliding surface. Unlike the embodiment described above, the gap depth end portion 19 can be accurately matched, so that the gap depth end portion 19 shifts while maintaining the advantages of the embodiment shown in FIG. An increase in unnecessary inductance and a decrease in magnetic resistance in a magnetic gap can be suppressed to a low level.

When the contact angle β of the metal magnetic thin film 17 on the trailing side with the sliding surface of the medium is less than 20 degrees, the structural strength of the upper part 21 of the winding window is weakened. A short circuit of magnetic flux (indicated by an arrow) occurs at a portion, which is not preferable.

[0024]

According to the structure of the core thin film magnetic head described above, magnetic recording and reproduction can be performed without magnetic saturation even with a very small magnetic gap depth, so that recording and reproduction at a high recording density can be performed.

[Brief description of the drawings]

FIG. 1 is a side view of a core thin film magnetic head according to the present invention.

FIG. 2 is a side view of a core thin film magnetic head having a larger angle on the trailing side than on the leading side of the core thin film magnetic head according to the present invention;

FIG. 3 is an enlarged view of a gap portion of the core thin film magnetic head according to the present invention.

FIG. 4 is a perspective view showing a state in which the position of the core thin-film magnetic head according to the present invention is adjusted and welded with a jig;

5 (a) is a partially enlarged front view showing a tip shape of a winding window processing blade of a core thin film magnetic head according to the present invention. FIG. 5 (a) shows a tip shape of a blade for processing a leading side winding groove. Shows the tip shape of the blade for machining the winding groove on the trailing side

FIG. 6 is a side view of an example of a magnetic head according to the related art.

FIG. 7A is a perspective view illustrating a manufacturing process of a magnetic head according to a conventional technique. (B) is a figure which shows a metal magnetic thin film formation process. (C) is a figure which shows a welding process.
(D) is a diagram showing a step of slicing the magnetic head chip.

FIG. 8 is a side view of another example of the conventional magnetic head.

FIG. 9A is a perspective view illustrating a manufacturing process of a core thin-film magnetic head according to the present invention. (B) is a figure which shows a metal magnetic thin film formation process. (C) is a figure which shows a welding process.
(D) is a diagram showing a step of slicing the core thin-film magnetic head chip.

[Explanation of symbols]

 2 Metal magnetic thin film 3 Nonmagnetic substrate 5 Winding window 12 Metal magnetic thin film on trailing side 13 Metal magnetic thin film on leading side 14 Magnetic gap 16 Gap depth end portion

Claims (4)

(57) [Claims] 1. A core thin-film magnetic head comprising: a pair of non-magnetic substrates; and a metal magnetic thin film formed on the pair of non-magnetic substrates. Is formed, and the metal magnetic thin film is an apex portion of the winding window.
A magnetic gap is formed on the inner peripheral surface of the winding window including the C-shaped opposed portion, and the metal magnetic thin film of the apex portion of the winding window is opposed to each other with a magnetic gap material interposed therebetween. A core thin-film magnetic head, wherein a depth of a facing portion of the metal magnetic thin film forming the magnetic gap in a gap depth direction is formed deeper on a trailing side than on a leading side. 2. The core thin film magnetic head according to claim 1, wherein an area of a portion of the metal magnetic thin film exposed to the medium sliding surface is smaller on a trailing side than on a leading side. 3. The core thin film magnetic head according to claim 2, wherein the contact angle of the metal magnetic thin film with the medium sliding surface is larger on the trailing side than on the leading. 4. A contact angle between the metal magnetic thin film forming the magnetic gap and the medium sliding surface on the trailing side is 20.
4. The core thin-film magnetic head according to claim 3, wherein the angle is from 60 to 60 degrees.