JPS6299903A - Magnetic head for vertical recording - Google Patents

Abstract

PURPOSE:To measure the depth of gap by forming a gap depth control film made of a laminated structure of film or thin plate or a single layer to an auxiliary member. CONSTITUTION:The 1st auxiliary member 4 and the 2nd auxiliary member 4' consist respectively of high permeability magnetic materials 13, 13' and non- magnetic materials 14, 14' and gap depth control films 15, 15' are arranged at the boundary of the both. Then a main magnetic film 12 is clipped by the 1st and 2nd auxiliary members in sandwich shape to form a main magnetic core. In polishing a face of the main magnetic pole block opposing to the recording medium, the gap depth control films 15, 15' are exposed. That is, the gap depth (gd) is obtained by measuring the exposed width C of the gap depth control film 15 or 15'.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a perpendicular recording magnetic head that is suitable and practical for use in a perpendicular magnetic recording system.

[Background of the invention]

As a perpendicular magnetic recording system, the configuration shown in FIG. 9 has been proposed (for example, Japanese Patent Laid-Open No. 134706/1983).

That is, the auxiliary magnetic pole core 2 is excited by the excitation coil 10, forms a magnetic field with the main magnetic pole core 1, and magnetizes the magnetic recording medium 3 perpendicularly. Furthermore, in order to record at higher density, a main pole core structure as shown in No. 10 has been proposed. (For example, JP-A-52-147414),
The main magnetic pole film 12 is a magnetic thin plate or thin film with high saturation magnetic flux density and high magnetic permeability, such as sendust, permalloy, or an amorphous magnetic alloy. The main magnetic pole core is sandwiched between auxiliary members 3 made of material 14 in the form of a sandwich. With this structure, the magnetic resistance at the rear of the core is reduced and only the tip has a narrow magnetic pole with high saturation magnetic flux density, making high-density recording possible.

] - Figures are an enlarged example view of the main pole core shown in Fig. 10 and an enlarged view of the surface facing the magnetic recording medium.

In FIG. 11, if the length a is the gap depth, then
Since the recording and reproducing characteristics depend on the gap depth, it is necessary to define the gap depth a to a required depth with high dimensional accuracy. This gap depth can be measured from the side of the main pole core. but.

When polishing the head by embedding it in a slider, head mount, etc., it becomes extremely difficult to measure the gap depth from the side due to structural issues with the slider, etc. 6 Therefore, for perpendicular magnetic recording with a main pole core, There is a need for a structure and technology that can accurately measure the gap depth of the head from a direction other than the side surface of the main pole core.

[Purpose of the invention]

The object of the present invention is to overcome the drawbacks of the prior art.

An object of the present invention is to provide a perpendicular recording magnetic head having a structure that allows the gap depth to be easily measured.

[Summary of the invention]

In order to achieve the above object, the present invention provides a main pole core of a perpendicular recording magnetic head having a structure in which an auxiliary part H for protecting the main pole film is integrated with one end or the entire main pole film. A gap depth control film made of a single layer or a layered film or a thin plate was formed on the auxiliary member, and the gap depth could be measured by observing the surface of the main pole core facing the recording medium.

[Embodiments of the invention]

Embodiments of the present invention will be described in detail below with reference to FIGS. 1 to 10. FIGS. 1(A) and 1(B) are enlarged side views of the main pole core showing the first embodiment of the present invention, and FIGS.
It is an A' sectional view. Figure 1 ′(a),(b)
, 12 is a main pole film made of a magnetic material with high saturation magnetic flux density and high magnetic permeability, and 4 and 4' are first and second auxiliary members for magnetically and mechanically assisting the main pole film 12. It is. The second auxiliary member 4 and the second auxiliary member 4' are respectively made of high permeability magnetic materials 1.3 and 13' and non-magnetic materials 14 and 14'. 15 and 15' are arranged. The main pole film 12 is sandwiched between the first and second auxiliary members to form a main pole core. In FIG. 1(A), t is the thickness of the main pole film 12, and θ is the thickness of the main pole film 1.
2 and the end surfaces of the gap depth control films 15 and 15', b is the depth of the gap depth control film, and gd is the gap depth to be determined. On the other hand, FIG. 1(b) shows a sectional view taken along line AA' in FIG. 1(a). Here, T is the core width and C is the exposed width of the gap depth control film.

Next, the 811 constant of the gap depth will be explained.

As shown in the AA' cross-sectional view of FIG. 1B, when the recording medium facing surface of the main pole block is polished, the gap depth control films 15 and 15' are exposed. That is, by measuring the exposed width C of one of the gap depth control films 15 or 15', the gap depth gd can be determined using the following formula (gd=b-C/lanθ), where b is the first figure(
This is the depth of the gap depth control films 15, J, and 5' shown in a), which can be measured in the state of the core before assembling the slider, and can also be calculated from the thickness of the gap depth control film. 0 is the main pole film 12 and the gap depth control films 15 and 15
This is the angle formed by the end surface of 0'' and an arbitrary angle can be selected as θ≦906.

Note that the measurement of the gap depth can be started when the point P shown in FIG. gd
The thickness of the gap depth control films 15 and 15' must be determined in consideration of this.

Other Embodiment 1 For example, as shown in FIG. 3, when one auxiliary member 4 and the other auxiliary member 4' are joined with different heights, the gap depth is first controlled in the gap depth polishing process. Preferably, the gap depth is defined by the auxiliary member 4 on the side of point P that reaches the membrane.

This kind of structure is effective in keeping the gap depth measurement constant and has excellent workability, so it is preferable to intentionally shift the gap depth. It is sufficient if it is formed on the auxiliary member. Third
In this embodiment shown in the figure, it is preferable to form it on the auxiliary member 4 side.

Next, the constituent materials of the main pole core of the present invention will be described. In FIGS. 4(a) and 4(b), the main magnetic pole film 12 is N1-F'
e alloy, F a -A n -S i alloy, Fa-8i
It is made of a thin film with high saturation magnetic flux density and high magnetic permeability, such as an alloy or an amorphous magnetic alloy. The film thickness t is 0.1 μm to 1
It is set to about μm.

The magnetic materials 13 and 13' of the auxiliary members 4 and 4' are M
High magnetic permeability bulk materials such as n-Zn ferrite and Ni-Zn ferrite are used. Also, non-magnetic materials 14 and 1
4' is made of glass or the like. Gap depth control film 15
, 15' are made of a non-magnetic material such as S x Oz r A Q 2 Oa v high melting point glass, high hardness carbide, oxide, nitride, or other ceramic material.

These nonmagnetic materials are preferably formed by thin film forming techniques such as sputtering and vapor deposition.

Although its thickness is not particularly specified, it is preferably 5 μm to 50 μm.

Next, regarding the second embodiment of the present invention, FIGS.
(b)). Hereinafter, the same materials and members will be denoted by the same reference numerals as in FIG. 1, and their explanation will be omitted. Fifth
(a) and (b) show a main pole core in which the gap depth control film is multilayered with two types of materials. For example, gap depth control films 15 and 16 as shown in FIG.
When gap depth polishing is performed on a main pole core having alternating layers, a multilayer film is exposed on the surface facing the recording medium as the polishing progresses, and the number of layers increases. That is, the gap depth can be measured by observing the number of exposed layers. The thickness of the multilayer film is determined by the required gap depth accuracy, and layers of several microns may be swept evenly, and as the gap depth becomes shallower, it is effective to increase the dimensional accuracy by making them denser. . In addition, gap depth control [15
It is also possible to stack the gap depth control film 16 mainly as an intermediate layer. For example, the main gap depth control film 15 is set to 1 to 5 μm, and the gap depth control film 31W416, which is the intermediate layer, is set to 0.05 to 0.5 μm.
Let it be μm. Furthermore, it is a good idea to change the color depending on the material selected.

Next, embodiments of the present invention will be described in more detail. 6th
As shown in the figure, the main pole film 12 is a Co-Zr-W amorphous alloy (B 5-1200 Gauss) with a thickness of 0.5 μm.
, Mn-Zn ferrite was used for the auxiliary member 113, lead glass was used for the auxiliary member 14, and a 5iOz single layer film with a thickness of 15 μm was used as the gap depth control film 15. Lead glass was used as the nonmagnetic material 17 for the main pole. A perpendicular recording magnetic head having a structure in which an auxiliary magnetic pole core made of Mn--Zn ferrite was sandwiched from both sides for the auxiliary magnetic pole 18 was used, and this head was incorporated into a slider to perform gap depth polishing. As a result, ±0.5 for a gap depth of 10 μm
It was confirmed that the gap depth could be controlled with micrometer accuracy.

Next, an example of a method for manufacturing the main pole core of the perpendicular recording magnetic head of the present invention will be described below. Figures 7 and 8
This figure is a multi-piece block perspective view schematically showing a method for manufacturing the main pole core of the perpendicular recording magnetic head of the present invention shown in FIG. 4. First, M n −Z as shown in FIG.
A gap depth control film 15 made of 5 iOz is formed with a thickness of 5 to 50 μm using a sputtering method on the side surface of the V-shaped groove of the auxiliary member 13 made of n-ferrite, and a wandering magnetic material 14 made of lead glass is formed thereon. Fill it and cut it at the specified position. After cutting, the bonding surface was mirror-polished as shown in FIG. 8, and then a main pole film 12 made of a Go-Zr-W amorphous alloy was formed on one of the auxiliary members 4 using a sputtering method, and the other was The main pole core of the perpendicular recording magnetic head as shown in FIG. 4 is obtained by bonding the auxiliary member 4' with glass or resin and cutting it at a predetermined position.

〔Effect of the invention〕

By creating a structure in which a single-layer or multilayer gap depth control film is provided at the boundary between the magnetic auxiliary member and the non-magnetic auxiliary member near the recording medium facing surface of the main pole core, the perpendicular recording magnetic head The gap depth can be machined with high dimensional accuracy. For example, ±0 for a gap depth of 10 μm.
．． Control with an accuracy of 5 μm is possible. Further, according to the present invention, since the required depth can be controlled while #Itm the gap depth control film that is cursed on the surface facing the recording medium, measurement is easy and mass productivity is also excellent.

[Brief explanation of drawings]

1 and 2 are explanatory diagrams of the main pole core of the perpendicular recording magnetic head according to the present invention, in which (a) shows a side view and (b) shows a cross-sectional view, and FIG. 1 is a side view of the main pole core of a magnetic head for perpendicular recording according to the present invention, and FIGS. 4 and 5 are side views of the core of a practical magnetic head for perpendicular recording according to the present invention. , a plan view of the surface facing the recording medium is shown in (b), FIG. 6 is a perspective view showing an embodiment of the main pole core of the recording magnetic head according to the present invention, and FIGS. The figure is an assembled perspective view showing an outline of the method for manufacturing the main pole core of a magnetic head for perpendicular recording according to the present invention, FIG. 9 is an explanatory diagram showing the principle of conventional perpendicular magnetic recording, and FIG. 10 is a conventional perpendicular recording magnetic head. A side view of the main pole core of the magnetic head, and FIG. 11 is an enlarged view of the vicinity of the recording medium facing surface of the main pole core shown in FIG. 10.

Claims (1)

[Scope of Claims] 1. A main magnetic pole made of a thin film of a high magnetic permeability magnetic material, and a main magnetic pole core serving as an auxiliary member that is joined and integrated so as to sandwich the main magnetic pole from both sides, the auxiliary member is a composite of a non-magnetic material and a magnetic material extending from the surface facing the magnetic recording medium to a desired position, and at least one layer of gap depth control film is formed at the boundary between the non-magnetic material and the magnetic material. A perpendicular recording magnetic head characterized by: 2. The boundary between the non-magnetic material and the magnetic material of the main pole auxiliary member is inclined toward the main pole, and a gap depth control film with a multilayer structure is formed at this boundary, which changes the gap depth. 2. The perpendicular recording magnetic head according to claim 1, wherein the number of layers of the gap depth control film changes when observed from a surface facing a magnetic recording medium.