JPH04147410A - Magnetic disk - Google Patents

Abstract

PURPOSE:To realize satisfactory recording and reproduction for a high coercive force recording medium by constituting magnetic alloy films by means of specified soft magnetic films consisting of more than one kind of element which is selected from among iron-nitrogen-oxygen, metal excepting iron and metalloid. CONSTITUTION:The magnetic alloy thin films 3 and 13 of high saturation magnetic flux density are adhered and formed on the abutting surfaces of respective magnetic core parts 1 and 11 including track width restriction grooves 2 and 12, and magnetic core halfbodies I1 and I2 are formed. In such a case, the magnetic alloy films 3 and 13 are the soft magnetic films consisting of at least more than one element selected from among iron-nitrogen-oxygen, metal excepting iron or metalloid. The soft magnetic films are expressed by the constitution expression of FeXNYOZMV and it has the relation of 1<=y<=10, 0.1<=z<=10, 0.5<=v<=6 and x+y+z+v=100. Thus, high saturation magnetic flux density is held, coercive force is small, thermal stability is superior and recording and reproducing efficiency for the high coercive force medium can be improved even if structure is not made into multi-layer.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a magnetic head used in a magnetic recording/reproducing device, and particularly to high-density magnetic recording used in the fields of audio, video, computers, etc. The present invention relates to a suitable magnetic head.

(Conventional technology) In recent years, the need for higher density and wider band magnetic recording has increased, and high-density recording has been achieved by using magnetic materials with high coercive force in magnetic recording media and narrowing the recording track width. are doing. Saturation magnetic flux density Bs is used as a magnetic head material for recording and reproducing on magnetic recording media with high coercive force.
There is a need for magnetic alloys with high magnetic properties, and magnetic heads using sendust alloys, amorphous alloys, etc. for part or all of the core have been proposed.

(Problem to be Solved by the Invention) However, as the coercive force of magnetic recording media continues to increase and the coercive force exceeds 20,000 e, magnetic heads using sendust alloys and amorphous alloys are unable to achieve good magnetic recording and reproduction. becomes difficult. Magnetic alloys containing iron as a main component, such as iron nitride and Fe-St alloys, are known as alloys for magnetic heads that have a higher saturation magnetic flux density Bs than sendust alloys and amorphous alloys.

However, conventionally known magnetic alloys with high saturation magnetic flux density have large coercive force HC and are insufficient as materials for magnetic heads as they are, so magnetic alloys with low coercive force such as sendust alloy and permalloy are used. A magnetic head made of a magnetic material with a multilayer structure using the material as an interlayer film has been proposed.

However, in such a magnetic head, there are problems in that creating a multilayered magnetic material requires a lot of man-hours and costs, and it is difficult to maintain reliability.

In particular, in order to obtain a magnetic film thickness of several μm or more, it is necessary to use a magnetic material with a multilayer structure of 100 or more layers depending on the case, and the range of use has been limited. In order to solve this problem, the present inventors proposed that a single-layer magnetic alloy with high Bs and low Hc can be obtained using FeN-0 alloy, but from the viewpoint of thermal stability, it is generally used in magnetic heads. The problem was that it was not suitable for the glass molding process, which is a standard manufacturing method.

Therefore, the present invention maintains a high saturation magnetic flux density without having to have a multilayer structure, has a small coercive force, and uses a magnetic alloy with excellent thermal stability for at least a part of the magnetic head.
An object of the present invention is to provide a magnetic head with excellent recording and reproducing efficiency for a high coercive force medium.

(Means for Solving the Problem) The present invention has been made to solve the problem, and includes a magnetic core half made of an oxide magnetic material and a magnetic alloy film, and these magnetic core halves are connected to each other. In the magnetic head formed by abutting each other with a non-magnetic gap material in between, the magnetic alloy film is a soft magnetic alloy film made of at least one element selected from iron-nitrogen-oxygen and metals or metalloids other than iron. This soft magnetic film is FeXNyO2My
It is represented by the composition formula: l≦y≦l010.1≦z≦10.5≦v≦6, x +
The present invention provides a magnetic head having the relationship: y + z + v -100 (where M is at least one element selected from metals or semimetals other than iron).

(Embodiment) FIG. 1 is an external perspective view of an embodiment of a magnetic head to which the present invention is applied, and FIG. 2 is an enlarged plan view of the main part of FIG. 1.

In this magnetic head I, near the abutting surface of the magnetic core portion 1.11 made of an oxide magnetic material, a track width regulating groove 2°12 for regulating the track width is cut out in a substantially arc shape from both sides. It's dark. Further, one magnetic core portion 1 is formed with a winding groove 21 for winding a coil for supplying signals to the magnetic head.

Then, a high saturation magnetic flux density is applied to the abutting surfaces of each of the magnetic core parts 1 and 11 continuously from the front gap forming surface to the back gap forming surface, including the inside of the track width regulating groove 2.12. A magnetic alloy thin film 3.13 is deposited to form the magnetic core halves II, 12.

Furthermore, an operating gap g is formed by bringing parallel portions 3a and 13a formed on the contact surfaces of these magnetic alloy thin films 3 and 13 into contact with each other. In addition, a non-magnetic material 22 is provided in the track width regulating groove 2.12 to regulate the track width and prevent wear of the magnetic alloy thin films 3 and 13.
．． 22 is melt-filled.

In the present invention, the magnetic alloy thin films 3 and 13 are made of Fe
It is composed of a magnetic alloy material represented by the composition formula xNvO2My (where M is at least one element selected from metals or semimetals other than iron).

Here, the magnetic alloy thin film represented by the composition formula F eXNy O2My will be explained.

3 and 4 show Fax-NY-0□- used as a magnetic alloy thin film in the magnetic head according to the present invention.
FIG. 3 is a diagram showing changes in coercive force ()lc) depending on the heat treatment temperature of a conventional example FeN alloy when M is AI or Hf in a magnetic material represented by the compositional formula Mv.

As this figure shows, the FeN alloy is heat treated at a temperature of 800°C.
At this time, He is relatively low, but when the temperature exceeds 300°C, He increases rapidly.

On the other hand, it can be seen that the magnetic material used in the magnetic head of the present invention has a small Hc and excellent thermal stability.

Therefore, the glass welding process formed through the gap of non-magnetic material can be performed stably.

Table 1 Table 1 shows Ti and Zr as M in the deposited Fe-N alloy, especially Fe-No-M alloy.

It shows the relationship between the respective content, saturation magnetic flux density (Bs), and coercive force (He) when Hf etc. are applied, and the content is determined by ESCA (X-ray photoelectron spectroscopy), E
It is expressed in atomic % by quantitative analysis using PMA (X-ray microanalyzer method), etc., but an error of about ±20% is expected. The coercive force is the value when heat treatment is performed in vacuum, and the heat treatment temperature is 400° C. here. Among these, sample number 1 is the result when only nitrogen is contained in Fe. Sample numbers 2 to 12 are magnetic alloy films used in the present invention.

(Left below) Table 2 shows the Fe-N alloy formed into a film, especially the FeN-0-M
In the alloys, St and B are used as M.

This shows the relationship between the content, saturation magnetic flux density (Bs), and coercive force (He) when AI, Ga, C, and Ge are applied. ), quantitative analysis using EPMA (X-ray microanalyzer method), etc., and it is expressed as atomic %, but an error of about ±20% is expected.

Coercive force is the value when heat treatment is performed in vacuum,
The heat treatment temperature here is 400°C.

Among these, sample number 1 is the result when only nitrogen is contained in Fe. Sample numbers 2 to 10 are magnetic alloy films used in the present invention.

What is shown in FIG. 5 shows the relationship between the nitrogen content and the saturation magnetic flux density Bs in the Fe--N alloy. As this figure shows, when the nitrogen content is less than the original atomic weight of 1O, Bs
A high Bs magnetic alloy with a force of 15 kG or more can be obtained. Also,
Similar results are obtained when M is less than the original atomic weight of IO.

Here, when the nitrogen content is less than 1 atomic %, no significant effect of nitrogen is observed, and He hardly decreases.

On the other hand, as is clear from Tables 11 and 2, when the nitrogen content is 1 atomic % or more, the effect of nitrogen becomes noticeable. Therefore, the nitrogen content is 1 to 10 atomic percent.
When this is the case, a magnetic alloy film with high Bs and low He can be obtained.

On the other hand, when looking at the oxygen content, when the oxygen content is less than 0.1 atomic %, no significant effect of oxygen is observed, and He hardly decreases.

On the other hand, it can be seen that when the oxygen content is 0.1 atomic % or more, the effect of oxygen becomes remarkable.

Therefore, when the oxygen content is 0.1 to 10 at%,
A magnetic alloy film with high Bs and low Hc can be obtained.

Here, if the total content of Ti, Zr, Hf, St, B, AI, etc. is less than 0.5 atomic %, no significant effect on lowering HC and improving thermal stability will be observed. When the amount exceeds atomic %, an increase in He occurs.

Therefore, at least one selected from metals or metalloids
When the total content of more than one type of elements is 0.5 to B atomic %, a magnetic alloy film with high Bs, low Hc and excellent thermal stability can be obtained.

FIG. 6 is a graph showing the relationship between the magnetic permeability and frequency of the magnetic alloy film used in the present invention when the film thickness of this alloy is 2 μm.

The magnetic alloy film used in the present invention has a high magnetic permeability of 5000, and can provide sufficient reproduction efficiency as a magnetic head.

In addition, in the description of this example, Ti, S
Although the explanation has been made using L, Ga, W, etc., it is needless to say that the material is not limited thereto.

Here, a comparison is made between the Fe-N-0-M alloy film, which is a high-performance material used in the magnetic head of the present invention, and Sendust, an amorphous alloy which is a magnetic material that can be bonded to glass. It is shown as Table 3.

(Margin below) Table As is clear from Table 3, when using a high He medium to achieve high recording density, Fe-N-0-
It can be seen that the M-based magnetic alloy film is most suitable.

The composition range that makes the best use of the characteristics of this magnetic material is 1≦y≦
10.0.1≦2≦10.0.5≦v≦6x+y+z10v-100 (numbers are atomic %, M is at least one element selected from metals or semimetals other than iron) It is.

Note that various conventionally known methods can be considered as a method for forming this magnetic alloy film, but among them, a vacuum thin film forming technique is suitable.

Examples of the vacuum thin film forming technique include sputtering, ion beam sputtering, ion blating, vacuum evaporation, cluster ion beam, and the like.

Since the present invention can be implemented without making any equivalent changes to the conventional structure, manufacturing method, or process, it can be said that its practical value is extremely high.

Although one embodiment of the present invention has been described above, the present invention is not limited to this embodiment and can be applied to magnetic heads of various structures without departing from the spirit of the present invention. for example,
As shown in FIG. 7, the mating surfaces of the magnetic core portions 30 and 31 made of oxide magnetic material are each obliquely cut out to form an inclined surface 30a.

31a, and FexNy is placed on the inclined surfaces 30a and 31a.
A magnetic head in which magnetic alloy thin films 32 and 33 represented by the compositional formula Mz are formed, magnetic core halves 11 and 12 are formed respectively, and the abutting surfaces of these magnetic alloy thin films 32 and 33 are used as an operating gap g. Also good. In addition, each magnetic core part 3
0.31, a track width regulating groove 34.35 is cut out to regulate the track width, and this track width regulating groove 34.3
5 and a non-magnetic material 36.5 in the magnetic alloy thin film 32.33.
37 is melt-filled. In this magnetic head, the track width can be regulated by the thickness of the magnetic alloy thin films 32 and 33, so that it is possible to narrow the track and is suitable for high-density recording.

FIG. 8, FIG. 9, and FIG. 10 each show other embodiments of the magnetic head to which the present invention is applied, and are enlarged views of the main parts thereof as seen from the medium contacting surface. Note that the same parts as in FIGS. 1 and 2 are denoted by the same reference numerals, and detailed explanation thereof will be omitted.

In FIG. 8, similar to FIGS. 1 and 2, the track width regulating grooves 2 and 12 for regulating the track width are cut out in a substantially arc shape from both sides, but the operating gap g is inclined. In this way, the regulating grooves are configured to be shifted by a predetermined portion.

9 and 10 show track width regulating grooves 2, 12 after depositing magnetic alloy thin films 3, 13 represented by the composition formula FexN, 07Mv on a substrate made of an oxide magnetic material.
A magnetic head formed in such an order as to form
In FIG. 10, like FIG. 8, the operating gap g is inclined. Figure 11 shows FexNyO□Mv
A coercive force of 1940 is obtained by the magnetic head 1 according to the present invention using Hf as M in a magnetic alloy thin film represented by the composition formula: and the magnetic head 2 using a conventional amorphous CO alloy thin film.
This figure shows the difference in input/output characteristics of 0e recording media. As this figure shows, a magnetic head 1 according to the present invention
It can be seen that compared to the conventional magnetic head 2, better recording and reproducing is performed on a high coercive force medium.

(Margin below) Table (B) Magnetic film specification table 4 is for explaining this Fig. 11, in which (A) shows the measurement conditions of the input/output characteristics, and (B) shows the measurement conditions for the input/output characteristics. These are the magnetic film specifications.

Note that when Fe-Al5t (Sendust alloy) is used as the magnetic alloy thin film, for example, the Al in the Sendust alloy
However, when the Fe-N-
In the 0-M alloy, since M forms a nitride in the alloy, there is little reaction with the oxide magnetic substrate, so pseudo gaps are less likely to occur.

Therefore, there is an advantage that pseudo pulses are less likely to occur during reproduction due to pseudo gaps.

(Effects of the Invention) As detailed above, according to the magnetic head of the present invention, the magnetic alloy thin film constituting the working gap and serving as the main core has a high saturation magnetic flux density, a small coercive force, and a low magnetic permeability. Because it is a magnetic alloy thin film expressed by the composition formula FezNYOZMV, which is large and has excellent thermal stability (where M is at least one element selected from metals or semimetals other than iron), it has a high coercive force. Good recording and reproduction can be performed on the medium.

Further, according to the present invention, since a magnetic alloy thin film as described above is used, a pseudo gap does not occur, and therefore, pseudo pulses are less likely to occur during reproduction. Furthermore, according to the present invention, there is no need to change the manufacturing process of conventional magnetic heads, and there is no decrease in production efficiency or accuracy, so it is easy to manufacture magnetic heads with features such as high reliability and high density. This is what can be obtained.

[Brief explanation of the drawing]

FIG. 1 is an external perspective view of an embodiment of a magnetic head to which the present invention is applied, FIG. 2 is an enlarged plan view of the main part of FIG. 1, and FIGS. 3 and 4 show He Diagram showing changes,
Fig. 5 is a graph showing the nitrogen content and saturation magnetic flux density (Bs), Fig. 6 is a graph showing the relationship between the magnetic permeability and frequency of the magnetic alloy film used in the present invention, and Figs. 11 is an enlarged plan view of a main part of another embodiment of the present invention, and FIG. 11 is a diagram showing input/output characteristics of a magnetic head according to the present invention and a conventional magnetic head. ■...Magnetic head, 1゜1...Magnetic core part, 3゜3...Magnetic alloy thin film.

Claims (1)

[Claims] In a magnetic head in which a magnetic core half is constituted by an oxide magnetic material and a magnetic alloy film, and these magnetic core halves are abutted against each other with a non-magnetic gap material interposed therebetween, the magnetic alloy film is , a soft magnetic film made of iron-nitrogen-oxygen and at least one element selected from metals or metalloids other than iron, and this soft magnetic film is made of Fe_XN_YO_ZM_
Represented by the composition formula V, 1≦y≦10, 0.1≦z≦10, 0.5≦v≦6, x
A magnetic head characterized by having the following relationship: +y+z+v=100. (However, M is at least one element selected from metals or semimetals other than iron)