JPS62157307A - Magnetic head - Google Patents

Abstract

PURPOSE:To obtain a magnetic head excellent in an electromagnetic transfer characteristic, reliability and productivity by constructing the surface forming a ferromagnetic thin film of two tilting surfaces in the vicinity of a magnetic gap at the prescribed angle with respect to a magnetic gap forming surface. CONSTITUTION:The ferromagnetic thin metallic films 15 and 19 are formed on the ferromagnetic thin film forming surfaces 13 and 14 of a joint surface obtained by obliquely notching magnetic cores 11 and 12, thereby constituting a magnetic core half. Core halves 21 and 22 are butted through a gap member, and the abutting surface of the thin metallic films 15 and 19 becomes the magnetic gap (g) of track width. The thin metallic film forming surfaces 13 and 14 are constructed of tilting surfaces 13a and 14a formed at an angle theta with respect to the magnetic gap forming surface, and tilting surfaces 13b and 14b at an angle alpha, and have bending points 13c and 14c. The angles theta and alpha are set to 10 deg.<theta<=35 deg., and 45 deg.<=alpha<=70 deg., respectively. Thus an electromagnetic transfer characteristic is further improved, and crosstalk is reduced.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a magnetic head, and in particular, a magnetic gap is formed by butting ferromagnetic metal thin films against each other via a gear or a spacer, and a core This relates to a so-called composite magnetic head in which most of the magnetic head is formed of ferromagnetic oxide.

[Summary of the invention]

In the present invention, a magnetic core half is formed from a magnetic core part made of a ferromagnetic oxide and a ferromagnetic metal thin film formed by a vacuum thin film forming technique on the ferromagnetic thin film forming surface of the magnetic core part. A magnetic head in which a magnetic gap is formed by making magnetic metal thin films face each other in series, and the ferromagnetic bacteria Ill formation surface and the magnetic gap formation surface are inclined at a predetermined angle on the surface facing the magnetic recording medium. In,
The ferromagnetic thin film forming surface is inclined at an angle θ of 10'<θ≦35'' with respect to the magnetic gap forming surface in the vicinity of the magnetic gap (approximately 456
By configuring the magnetic head with an inclined surface inclined at an angle α such that ≦α≦70°, the track width can be expanded and the magnetic groove can be provided with less influence of crosstalk and pseudo gaps.

[Conventional technology]

In the field of magnetic recording, the recording density and frequency of information signals are increasing, and in response to this trend, powders of ferromagnetic metals such as Fe, Co, and Ni are being used as magnetic powders as magnetic recording media. So-called metal tapes using 6i metal materials, and so-called vapor deposition tapes in which 6i metal materials are directly deposited on a base film by vacuum thin film forming techniques such as vapor deposition, have been put into practical use.

By the way, since this type of magnetic recording medium has high coercive force and residual magnetic flux density, the head material of the magnetic head used for recording and reproducing must have a high saturation magnetic flux density.

It is required to have a high i3 magnetic flux. For example, conventionally,
Ferrite materials, which are often used as head materials, have a low saturation magnetic flux density and cannot cope with the above-mentioned increase in coercive force.

Conventionally, in order to support magnetic recording media with high coercive force, a ferromagnetic metal '7ii film having a high saturation magnetic flux density is deposited on a non-magnetic substrate such as ceramic or a magnetic substrate such as ferrite. A so-called composite magnetic head has been proposed in which magnetic metal thin films are butted against each other to form a magnetic gap.

However, in these conventional composite magnetic heads,
There are many problems in terms of productivity and reliability.

For example, a composite magnetic head has been proposed in which ferromagnetic metal thin films sandwiched between non-magnetic substrates such as ceramics are butted against each other, and the track width is determined by the thickness of the ferromagnetic metal thin films. Since the entire magnetic path is made up of only a thin ferromagnetic metal film, not only does the magnetic resistance increase and the efficiency decreases, but the ferromagnetic metal thin film must be deposited to a certain degree thicker to maintain a predetermined track width. However, there are problems such as a long time required for film formation.

Alternatively, a composite type magnetic head has been proposed in which the magnetic core portion is made of a ferromagnetic oxide such as ferrite, and a ferromagnetic metal thin film is coated on the magnetic gap forming surface of each magnetic core portion. In this case, since the magnetic path and the metal thin film are located in a direction perpendicular to each other, the influence of the pseudo gap is large, and there is a risk that eddy current loss will occur, leading to a decrease in the reproduction output, and sufficient reliability is not achieved. There are problems such as not being able to obtain it.

Therefore, in order to eliminate the above-mentioned drawbacks, the applicant first
Specification of Japanese Patent Application No. 58-250988 or Japanese Patent Application No. 1983
No. 0-153745 proposed a magnetic head in which a ferromagnetic metal thin film was obliquely deposited to improve reliability and productivity. Among them, the patent application No. 60-153745
The magnetic head described in the specification has a bend in the middle of the surface on which the ferromagnetic a film is formed, and even with a thin ferromagnetic metal thin film, a certain trunk width can be secured, and damage due to cracks can be ensured. It has the characteristics of high reliability and productivity.

[Problem that the invention seeks to solve]

The present invention aims to further improve such magnetic heads.

In other words, in the above-mentioned magnetic head, in addition to expanding the trunk width, we determined the optimal value of the inclination angle of the ferromagnetic thin film forming surface, taking into account crosstalk, pseudo gaps, reproduction output, etc., and achieved excellent electromagnetic conversion characteristics and reliability. .

The object of the present invention is to provide a magnetic head that is also advantageous in terms of productivity.

[Means for solving problems]

In order to achieve the above objects, the present invention has a magnetic core made of a ferromagnetic oxide and a ferromagnetic component of the magnetic core.
A magnetic core half is formed from a ferromagnetic metal thin film formed by vacuum thin film formation technology on the iyi film forming surface, and a magnetic gap is formed by making the ferromagnetic metal thin films face each other in series, A magnetic head in which the ferromagnetic thin film forming surface and the magnetic gap forming surface are inclined at a predetermined angle on the surface facing the magnetic recording medium, wherein the IAI magnetic thin film forming surface is adjacent to the magnetic gear forming surface in the vicinity of the magnetic gap. An inclined surface that is inclined at an angle θ of 10′<θ≦35″′ with respect to the magnetic gap forming surface, and 456≦α≦70 with respect to the magnetic gap forming surface.
It is characterized by being composed of a 1-degree slope inclined at an angle α.

(Function) Since the inclination angle of the ferromagnetic thin film forming surface is set to an angle θ of 10゛<θ≦35° with respect to the magnetic gap forming surface in the vicinity of the magnetic gap, the film thickness of the ferromagnetic metal thin film is Track width is ensured even if it is thin.

In addition, the above ferromagnetic 'iXj tl! By setting the inclination angle of the J forming surface to the above angle θ, the interface between the ferromagnetic metal thin film and the ferromagnetic oxide does not act as a pseudo gap.

Furthermore, the angle of the inclined surface far from the magnetic gap is set to 45°.
By setting ≦α≦70@, the volume of the magnetic core portion in the vicinity of the magnetic gap is ensured, and the contact area between the ferromagnetic metal thin film and the ferromagnetic oxide is expanded, and the reproduction characteristics are improved.

〔Example〕

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

FIG. 1 is an external perspective view showing an example of a composite type magnetic head to which the present invention is applied, and FIG. 2 is an enlarged plan view of a main part showing the surface in contact with a magnetic recording medium.

In this magnetic head, a magnetic core portion (11).

(12) is formed of a ferromagnetic oxide, such as Mn-Zn ferrite, and these magnetic core parts (11) and (12)
Ferromagnetic thin film forming surface (13) with diagonally cut out bonding surface
, (14), a ferromagnetic metal thin film (15), which is a high magnetic permeability alloy, such as a Fe-Al-3i alloy film, is continuously formed from the front gap forming surface to the back gap forming surface (15), (19). The magnetic core halves (21) are formed using vacuum thin film forming technology.

(22) is configured. Then, these pair of magnetic core halves (21) and (22) are butted together via a gear knob material such as 5ins, and the above-mentioned ferromagnetic metal thin n.
.

The abutment surface of (19) is configured to be a magnetic gear knob g having a track width Tw.

Here, the ferromagnetic metal thin film forming surface (13), (1
4) is an angle θ with respect to the joining surface which is the abutting surface of the magnetic core halves (21) and (22), that is, the magnetic gap forming surface (16) when viewed from the surface facing the magnetic recording medium. The first inclined surface (13a), (14
a), and a second inclined surface (13b) inclined at an angle α with respect to the magnetic gap forming surface (16),
(14b), and has obtuse angle bent portions (13c) and (14c) in the middle.

Then, first inclined surfaces (13a), (14
a) Ferromagnetic metal GT film (15) to be deposited on top
, (19) are butted against each other to form a magnetic gap g.

A first inclined surface (
13a), (14a) and magnetic gap forming surface (16
) is set within the range of 10° and θ≦35°. When this inclination angle θ exceeds 356, the ferromagnetic metal thin film (1
5) and (19), a sufficient film thickness must be ensured, which is undesirable as productivity deteriorates. Conversely, when the inclination angle θ is 10" or less, the magnetic gap g and the first inclined surface (13
a) and (14a) approach parallelism, 1. Crosstalk and pseudo gaps occur, degrading recording and reproducing characteristics.

Further, second inclined surfaces (13b) and (1) are formed continuously with the first inclined surfaces (13a) and (14a).
4b) and the magnetic gap forming surface (16)
is set within the range of 45°≦α≦70″. If this inclination angle α exceeds 70°, the volume of the magnetic core portions (11) and (12) decreases near the magnetic gear g, and the reproduction output decreases. Inconveniences occur such as a decrease in the angle of inclination or a deterioration of wear resistance.On the other hand, if the groove is formed so that the inclination angle α is not 45°, crosstalk increases and the reliability of the head decreases, which is preferable. do not have.

In addition, near the magnetic gear g, that is, on both sides of the magnetic gap g on the surface facing the magnetic recording medium, the ferromagnetic metal thin films (15), (19) regulate the track width.
A non-magnetic material (17L (18)) is melt-filled to prevent wear.

In addition, in this example, the magnetic core part (11)
, (12) Track width regulating groove (Ilb) formed in
, (12b) are formed so that the shape of the interface between the non-magnetic material (18) and the ferromagnetic oxide is curved. The trunk width regulating grooves (11b) and (12
In addition to securing the distance between the ferromagnetic oxide facing b) and the ferromagnetic metal a film (15), (1'l) facing it, the symmetrical balance of this groove allows the ferromagnetic oxide to be The stress may be reduced to prevent microcracks from occurring in the magnetic core portions (11) and (12).

On the other hand, the material of the ferromagnetic metal thin films (15) and (19) is a ferromagnetic amorphous metal alloy, a so-called amorphous alloy (for example, one or more elements of Fe, Ni, and co, and P, C, B, An alloy consisting of one or more elements of Si,
Or A1 with this as the main component. Ge.

Be, Sn, Inn, Mo, W, Ti, Mn, Cr.

Metal-metalloid amorphous alloys such as alloys containing Zr, HE, Nb, etc., or metal-metal amorphous alloys whose main components are transition elements or rare earth elements such as Co, Hf, Zr, etc.), Fe-Al- Sendust alloy, Fe-Aff alloy, Fe-3i alloy, Fe-3i-CO alloy, Permalloy, etc., which are 3i-based alloys, can be used, and their coating methods include flash vapor deposition,
Vacuum deposition.

Ion brating, spankling, clascou・
Vacuum thin film formation technology such as ion beam method is employed.

When using the above Fe-Al-3i alloy, its main components are Fe, A1. The composition range of Si is Af
Fi content is 2-10% by weight, Si content is 4-1%
It is preferable that Fe accounts for 5% and the balance is Fe. That is, when the above-mentioned Fe-At'-3i alloy is expressed as Fe, A11b 5ic (a, b, c represent the weight ratio of each component), its composition range is 70sa<g5 2≦b≦10 It is desirable that 4≦c515. Even if the above At' and Si are too small or too large, Fe = Aj! -The magnetic properties of the 3i-based alloy deteriorate.

It is also possible to replace a part of the Fe with at least one of Co and Ni.

The saturation magnetic flux density can be increased by replacing a portion of Fe with Co. In particular, the maximum saturation magnetic flux density can be obtained by replacing 40fi% of Fe with Co.

The setting ram of this Co is 0 to 60 for Fe.
It is preferably within the range of % heavy needles.

By replacing a portion of the Fe with Ni, the magnetic permeability can be maintained at a high level without reducing the saturation magnetic flux density. This Ni substitution (■) is 0 to 1 for Fe.
It is preferably within the range of 40%.

Furthermore, various elements may be added to the above-mentioned Fc-An-3i alloy as additives in order to improve corrosion resistance and wear resistance. Elements used as the above additives include:
Ma group elements including lanthanum series such as Sc, Y, La, Ce, Nd, Gd, f'ia group elements such as Ti, Zr, HE, Va group elements such as V, Nb, Ta, Cr, Mo, W
■A group elements such as Mn+=Tc+ Re, etc., Cu, Ag.

Ib group elements such as Au, Ga, In, Ge, Sn.

sb etc.

By the way, the above ferromagnetic metal 'iyJ film (15), (
19) is formed as a single layer by vacuum thin film formation technology in this example, and the tail is made of, for example, SiO2, TaZo,...
A12o,.

A plurality of layers may be laminated via a highly wear-resistant insulating material such as Zr○, Si3N, or the like. In this case, the number of laminated ferromagnetic metal thin films can be set arbitrarily.

Of the magnetic core halves (21) and (22), one of the magnetic core halves (22) is provided with an S wire groove (2o), and the coil is inserted into this winding groove (20). By winding it, a signal is supplied to or extracted from the magnet.

In the magnetic head configured in this way, the first inclined surfaces (13a), (14a) near the magnetic gear g
is formed so that 106<θ≦35° with respect to the magnetic gap forming surface (16), so even if the ferromagnetic gold JFvlJ films (15) and (19) are thin, a magnetic head with a wide track width can be formed. . Therefore, productivity is greatly improved.

Further, as described above, the interface between the ferromagnetic oxide and the ferromagnetic metal thin film, that is, the first inclined surface (13a), (14a
) is formed at a predetermined angle with respect to the magnetic gear g, so that crosstalk from adjacent or neighboring tracks is reduced, and the influence of the l-domain gap is also reduced.

Furthermore, a magnetic core half (21) which is a ferromagnetic oxide.

(22) a ferromagnetic metal thin film (15) deposited thereon;
(19) is the ferromagnetic metal thin film forming surface (13), (1
4) At the bent portions (13c) and (L4c), the magnetic core portions (11) and (12) and the ferromagnetic metal thin film (15)
, (19), the stress caused by the difference in the coefficient of thermal expansion is relaxed and dispersed, so damage such as cracking does not occur.

Furthermore, the ferromagnetic thin film forming surfaces (13) and (14) are
A bent part (13c) consisting of an obtuse angle in the middle part, (1
4c), the volume occupied by the ferromagnetic oxide increases in the vicinity of the magnetic gear g, improving wear resistance, and the ferromagnetic metal thin films (15), (
19) and the magnetic core portions (11) and (12) is expanded, and the recording and reproducing characteristics are improved.

By the way, the present invention is not limited to the above-described embodiments, and various other structures may be adopted without departing from the spirit of the present invention.

For example, as shown in FIG. 3, track width regulation '18 (31a), (3
2a) may also be formed. With such a configuration, for example, a distance between the ferromagnetic metal thin film (15) of one magnetic core half (35) and the magnetic core part (32) of the other magnetic core half (36) is ensured. Therefore, the effects of crosstalk can be further reduced. In FIG. 3, the same members as in FIGS. 1 and 2 are given the same reference numerals, and detailed explanations are omitted.

〔Effect of the invention〕

As is clear from the above description, in the present invention,
Since the ferromagnetic metal thin film forming surface is composed of two inclined surfaces inclined at different angles with respect to the magnetic gap forming surface, the abutting width (track width) of the ferromagnetic metal thin film in the vicinity of the magnetic gap can be adjusted. Can be expanded. Therefore, for example, the thickness of the ferromagnetic metal thin film to ensure a predetermined track width can be reduced, which is advantageous in terms of productivity.

In addition, in the present invention, since the inclination angle of each of the above-mentioned inclined surfaces is set to 106 × θ≦35° in the vicinity of the magnetic gap, and the inclination angle far from the magnetic gap is set to 45°≦α≦70＠, crosstalk occurs. It is possible to suppress the effects of gaps and pseudo gaps. Therefore, good electromagnetic conversion characteristics can be obtained.

Furthermore, since an obtuse-angled bent part is formed on the surface on which the ferromagnetic metal thin film is formed, strain caused by the difference in thermal expansion coefficient between the ferromagnetic metal thin film and the ferromagnetic oxide is dispersed and absorbed in this part, thereby preventing cracks. This results in a highly reliable magnetic head with no cracks.

Furthermore, by forming the above-mentioned bent portion, the volume occupied by the ferromagnetic oxide in the vicinity of the magnetic gap becomes larger, ensuring reproduction output and improving wear resistance, resulting in a highly reliable magnetic head. .

[Brief explanation of drawings]

FIG. 1 is an external perspective view showing an example of a magnetic head to which the present invention is applied, and FIG. 2 is an enlarged plan view of a main part showing the surface in contact with a magnetic recording medium. FIG. 3 shows another example of the present invention, showing the surface of a magnetic head in contact with a 61K recording medium, in which a part of the ferromagnetic metal thin film is cut out by a track width regulating groove near the magnetic gap. FIG. 3 is an enlarged plan view of main parts.

Claims (1)

[Scope of Claims] A magnetic core half is formed from a magnetic core portion made of a ferromagnetic oxide and a ferromagnetic metal thin film formed by a vacuum thin film forming technique on the ferromagnetic thin film forming surface of the magnetic core portion, A magnetic gap is formed by making the ferromagnetic metal thin films face each other in series, and the ferromagnetic thin film forming surface and the magnetic gap forming surface are inclined at a predetermined angle on the surface facing the magnetic recording medium. The head, wherein the ferromagnetic thin film forming surface has an inclined surface that is inclined at an angle θ of 10°<θ≦35° with respect to the magnetic gap forming surface near the magnetic gap, and a 45° angle with respect to the magnetic gap forming surface. ≦
1. A magnetic head comprising an inclined surface inclined at an angle α such that α≦70°.