JPH04105807U - thin film magnetic head - Google Patents

Abstract

(57) [Summary] [Purpose] The purpose of this invention is to realize a thin-film magnetic head that maintains the inherent advantage of a thin-film magnetic head, such as steep magnetic flux, and can perform high-density recording. shall be. [Structure] A coil 5 is sandwiched between insulating layers 12a and 12b and upper and lower core members 3 and 6. Metal magnetic films 11, 13 made of Sendust (registered trademark), which has a higher saturation magnetic flux density than magnetic ferrite, are placed on the gap forming parts 3c, 6c of the upper and lower core materials 3, 6 formed of magnetic ferrite with high magnetic permeability. , and a gap 14 is formed. [Effect] The gap forming portion 3 is formed by the metal magnetic films 11 and 13.
Magnetic saturation at c and 6c can be prevented, and high-density recording becomes possible.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention relates to a thin film magnetic head, particularly a thin film magnetic head with improved recording characteristics. Regarding.

0002

[Conventional technology]

Magnetic heads with various structures have been proposed, one of which is the 2. Description of the Related Art Thin film magnetic heads are known in which coils, etc. are formed using thin film technology.

0003 FIG. 4 is a cross-sectional view showing the configuration of the main parts of an example of a conventional thin film magnetic head. Same figure The thin film magnetic head 1 shown in FIG. Sea urchins are formed.

0004 A single material such as magnetic ferrite is placed on the substrate 2 made of non-magnetic material. A lower core 3 is formed, and an insulating layer 4a is formed thereon. Next, make the conductor into a spiral shape. (In FIG. 4, only the portion formed on the lower core material 3 is cut.) ), and an insulating layer 4b is further formed thereon. And insulation An upper core 6 made of the same material as the lower core 3 is formed on the layer 4b, and finally a protective layer 7 is applied to cover the entire body. cover.

[0005] The left side surface of the thin-film magnetic head 1 formed as described above is a recording medium (not shown). ) is the facing surface 1a. On this opposing surface 1a, a lower core 3 and an upper core 6 are disposed. The end surfaces 3a and 6a are arranged with an insulating layer 4a in between, and this gap becomes the gap 8 of the thin film magnetic head 1.

[0006] The thin-film magnetic head 1 having the above structure has a lower upper part than other so-called bulk type heads. The area of the end surfaces 3a and 6a of the core 6 and the lower core 3 facing the recording medium can be reduced. I can do that. As a result, the magnetic flux across the gap 8 is smaller in area than the end faces 3a and 6a. By flying in a concentrated manner, the slope of the magnetic flux with respect to the end surfaces 3a and 6a becomes steeper, and the upper The magnetic flux reaches a high position on the opposing surface 1a. That is, the magnetic flux becomes steep. and , when the thin-film magnetic head 1 with a steep magnetic flux is actually used, the deep part of the recording medium You can record in minutes and achieve reliable records. Especially magnetic disk recording In devices, recording characteristics are not affected by the gap size between the disk and magnetic head. Become. Effects such as this can be obtained.

[0007] Thin-film magnetic heads have the advantage of having a steep magnetic flux due to their structure. essentially has the following.

[0008]

[Problem that the idea aims to solve]

In recent years, the demand for high-density magnetic recording and reproducing processing has increased, and we are working to meet this demand. Magnetic heads require high saturation magnetic flux density during recording, and sufficient saturation magnetic flux density during playback. In order to obtain high playback sensitivity, high magnetic permeability is required, especially in the high frequency range. Ru. In the thin film magnetic head 1 having the above structure, in order to obtain the above effects, Because the area of the part facing the recording medium is reduced, bulk type heads The magnetic flux density is easily saturated compared to Achievement was hindered. This is because the lower core 3 and When a magnetic ferrite with high magnetic permeability is used as the material for the upper core 6, it generally has a high permeability. Magnetic materials with magnetic permeability have a low saturation magnetic flux density as a physical property of the material, so they can be used for high-density recording. was considered more difficult.

[0009] Therefore, the present invention was devised in view of the above-mentioned problems. A thin-film magnetic head that maintains the original strengths of magnetic heads and is capable of high-density recording. The purpose is to provide.

0010

[Means to solve the problem]

In order to achieve the above purpose, this invention In a thin film magnetic head comprising a pair of core materials made of a first magnetic material, A metal magnetic film made of a second magnetic material having a higher saturation magnetic flux density than the first magnetic material. , a thin film is formed on the pair of core materials, and a magnetic gap is formed between the respective metal magnetic films. It has a compact structure.

[0011]

[Effect]

A metal magnetic film made of a second magnetic material having a higher saturation magnetic flux density than the first magnetic material is By forming a magnetic gap between the pair of core materials, the magnetic The saturation magnetic flux density near the gap increases, preventing magnetic saturation during recording. . In addition, since the metal magnetic film is formed in a thin film shape, the surface of the core material facing the recording medium is area will not increase compared to before. For this reason, thin-film magnetic heads with steep magnetic flux conditions will remain unchanged.

0012

【Example】

FIG. 1 is a cross-sectional view showing the configuration of the main parts of the first embodiment of the thin-film magnetic head according to the present invention. , FIG. 2 is a front view of the thin film magnetic head shown in FIG. 1, viewed from the surface facing the recording medium. Note that FIG. 1 shows a cross section taken along line II in FIG. 2.

[0013] The thin film magnetic head 10 shown in FIG. 1 is the same as that shown in FIG. 4 except for the gap forming portion 10b. It has the same configuration as the conventional magnetic head 1. Therefore, the part corresponding to the part shown in FIG. The same numerals are used for the minutes. The configuration of the thin film magnetic head 10 will be described in detail below. Ru.

In FIG. 1, the left end side surface of the thin-film magnetic head 10 is an opposing surface 10a on which a recording medium (not shown) such as a magnetic tape faces in sliding contact or with a gap therebetween. In the case of this embodiment, recording and reproduction are performed by moving the recording medium in the Z ₁ -Z ₂ direction in the figure while facing the opposing surface 10a.

[0015] The substrate 2 forming a part of the opposing surface 10a is made of a non-magnetic material such as ceramic. The upper surface 2a is a flat surface. on this flat surface 2a , the lower core material 3 is formed into a thin film with the end surface 3a exposed to the opposing surface 10a. . This lower core material 3 is made of a magnetic material with high magnetic permeability such as magnetic ferrite. A thin film is formed on the substrate 2 by taring etc., and the film thickness dimension is the same as that of the main body. Approximately 5 μm in the portion 3b, and approximately 5 μm in the gap forming portion 3c near the opposing surface 10a. , it has been narrowed down to about 3 μm.

[0016] On the gap forming portion 3c of the lower core material 3, an end surface 11a is exposed on the opposing surface 10a. The exposed metal magnetic film 11 is formed into a thin film shape. This metal magnetic film 11 is For example, magnetic ferrite having a higher saturation magnetic flux density than the magnetic ferrite constituting the core material 3 It is formed from Dust (registered trademark) or the like. The film thickness dimension of the metal magnetic film 11 is A dimension of 1 μm or less that is thinner than the film thickness dimension (film thickness = 3 μm) of the gap forming portion 3c. It is considered a law.

[0017] The coil 5 is a conductive pattern formed in a spiral shape along the upper surface 2a of the substrate 2. (In Figure 1, the radial portion of the three-turn spiral is shown as a cross section.) , an insulating layer 12a is sandwiched between the parts above the lower core material 3, as shown in FIG. It is formed by

[0018] An insulating layer 12b is formed on the insulating layer 12a so as to cover the coil 5. An upper core material 6 made of the same material as the lower core material 3 is formed in the form of a thin film on the upper part of the core material. . This upper core material 6 has a main body portion 6 formed so as to cover the coil 5 with a convex curved surface. b (shown in a trapezoidal shape in FIG. 1 for convenience of illustration), and near the opposing surface 10a. It is composed of a gap forming part 6c. One end 6d of the main body 6b is a lower core. It is in contact with the end portion 3d of the material 3. In addition, the film thickness dimension of the upper core material 6 is the lower core material 6. Equivalent to material 3, the main body portion 6b is approximately 5 μm and the gap forming portion 6c is approximately 3 μm. It is.

[0019] The ends 3d and 6d of the upper and lower core materials 3 and 6 are located at the spiral center of the coil 5. The upper and lower core materials 3 and 6 are arranged from the center to the outermost periphery of the coil 5. The radius part up to is sandwiched. Further, the upper and lower core materials 3 and 6 are insulating layers 12a, It is electrically insulated from the coil 5 by the coil 12b. Therefore, the coil 5 is The structure is such that when an electric current is applied, the upper and lower core materials 3 and 6 are excited.

A metal magnetic film 13 with an end surface 13a exposed on the opposing surface 10a is formed at a position opposite to the metal magnetic film 11 below the gap forming portion 6c. This metal magnetic film 13 is made of the same material and has the same shape as the metal magnetic film 11. An insulating layer 12c is filled between the metal magnetic films 11 and 13, and as shown in FIG. 2, a gap 14 is formed along the _X1 - _X2 direction. The width dimension of the gap 14 in the X ₁ -X ₂ direction represents the track width of the thin film magnetic head 10 . Further, the distance between the gaps 14 is about 0.1 μm, which is the same as that of the conventional thin film magnetic head 1.

[0021] The gap forming portions 3c and 6c of the upper and lower core materials 3 and 6 explained above and the metal magnetic The films 11 and 13 and the insulating layer 12c form the gap type of the thin film magnetic head 10 described above. This constitutes the construction section 10b.

[0022] Further, a protective layer 7 made of a non-magnetic material is formed on the upper part of the upper core material 6, and The various thin films formed on 2 as described above are protected from external impact.

[0023] In this way, the upper and lower core materials 3 and 6 and the coil are formed as thin films on the substrate 2. 5. Insulating layers 12a, 12b, 12c, metal magnetic films 11, 13, and protective layer 7, All using general thin film forming technology such as sputtering, and photolithography technology. etc., and are formed in order from the side closest to the substrate 2.

[0024] In general, thin-film magnetic heads have a core material made of a thin film, as mentioned above. As a result, the area of the core material facing the recording medium can be reduced. The advantage is that the magnetic flux can be made steeper than bulk type magnetic heads. have. However, on the other hand, because the area is small, the magnetic flux density is saturated. For this reason, magnetic saturation occurs during recording, making high-density recording difficult. The problem was that it couldn't be done.

[0025] However, according to the thin film magnetic head 10 of this embodiment, the upper and lower core materials 3 and 6 The metal magnetic films 11 and 13 having a higher saturation magnetic flux density than the gap of the upper and lower core materials 3 and 6 are By forming gaps 14 in the gap forming portions 3c and 6c, the metal In the vicinity of the gap 14 of the upper and lower core materials 3 and 6 including the magnetic films 11 and 13 The saturation magnetic flux density becomes high, and the occurrence of magnetic saturation as in the conventional case is prevented. Therefore, If the thin film magnetic head 10 is used, higher density recording than before is possible.

[0026] Further, as mentioned above, the metal magnetic films 11 and 13 are smaller than the upper and lower core materials 3 and 6. Since the film is formed with a large thickness, the area of the end faces 11a and 13a becomes extremely small. Therefore , the end surfaces of the upper and lower core materials 3 and 6 including the metal magnetic films 11 and 13 (end surfaces 3a and 6a The area of the + end surfaces 11a, 13a) does not increase much compared to the conventional case. For this reason, Thin film magnetic fields have a steep magnetic flux due to the small area facing the recording medium. The original advantages of the magnetic head are maintained as they are in the thin film magnetic head 10 of this embodiment. Ru.

[0027] Furthermore, the thin-film magnetic head 10 includes magnetic ferrite with high magnetic permeability in the upper and lower core materials 3 and 6. Since a light is used, playback sensitivity is good during playback.

As described above, according to the thin film magnetic head 10 of this embodiment, high-density recording is possible, and the recording is ensured by the steep magnetic flux, resulting in good recording characteristics, and also good reproduction characteristics. It becomes possible to realize a thin film magnetic head. Furthermore, as shown in FIG. 2, by arranging a plurality of thin film magnetic heads 10 in parallel in the track direction (X ₁ -X ₂ direction) (only two, 10 _-1 and 10 _-2 are shown in FIG. ), it is possible to realize a high-density, multi-channel magnetic head.

[0029] Note that the present invention is not limited to the above embodiment, and the upper and lower core materials 3 and 6 may be The magnetic ferrite used may be a material such as permalloy, or may be a metal. The sendust used for the magnetic films 11 and 13 may be amorphous or other material. stomach.

[0030] A second embodiment shown in FIG. 3 is also conceivable. Figure 3 shows the thin film magnetic head according to the present invention. FIG. 2 is a cross-sectional view showing the configuration of the main part of a second embodiment of the invention.

[0031] The thin film magnetic head 20 of this embodiment is the upper part of the thin film magnetic head 10 shown in FIG. The entire gap forming portions 3c and 6c of the lower core materials 3 and 6 have a high saturation magnetic flux density. This is an example in which metal magnetic films 21 and 22 are substituted. According to this, the upper and lower core materials 2 The area of the exposed portions on the opposing surfaces 20a of the metal magnetic films 21 and 22 The areas of the end faces 21a and 22a of the metal It becomes smaller by the area of the end faces 11a and 13a of the magnetic films 11 and 13, and the thin film magnetic head Compared to the head 10, a steeper magnetic flux can be obtained.

[0032]

[Effect of the idea]

As described above, according to the present invention, the area of the surface of a pair of core materials facing the recording medium is The saturation near the magnetic gap of the core material can be improved without significantly changing compared to conventional methods. It is possible to increase the sum magnetic flux density, thereby preventing magnetic saturation during recording. I can do that. Therefore, the inherent advantage of a thin film magnetic head is that it can obtain a steep magnetic flux. Enables high-density recording without compromising performance, improving the recording characteristics of thin-film magnetic heads can be achieved.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing the configuration of the main part of a first embodiment of a thin-film magnetic head according to the present invention, showing a cross section taken along line II in FIG. 2;

FIG. 2 is a front view of the thin-film magnetic head shown in FIG. 1, viewed from a surface facing a recording medium.

FIG. 3 is a cross-sectional view showing the configuration of the main parts of a second embodiment of the thin-film magnetic head according to the present invention.

FIG. 4 is a cross-sectional view showing the configuration of a main part of an example of a conventional thin-film magnetic head.

[Explanation of symbols]

2 Board 3,24 Lower core material 5 coil 6,23 Upper core material 7 Protective layer 10,20 Thin film magnetic head 10a, 20a Opposing surface 10b, 3c, 6c gap forming part 11, 13, 21, 22 Metal magnetic film 12a, 12b, 12c insulating layer 14 Gap

Claims (1)

[Scope of utility model registration request] 1. A thin film magnetic head comprising a pair of core materials made of a first magnetic material, wherein a metal magnetic film made of a second magnetic material having a higher saturation magnetic flux density than the first magnetic material is attached to the core material of the first magnetic material. A thin film magnetic head having a structure in which each metal magnetic film is formed in the form of a thin film on a core material, and a magnetic gap is formed between the respective metal magnetic films.