JPH02148806A - Magnetic head - Google Patents

Abstract

PURPOSE:To obtain a magnetic film having predetermined magnetic properties and to improve recording/reproducing characteristics by composing Co-Nb-Zr amorphous magnetic alloy of Co, Nb and Zr. CONSTITUTION:In a magnetic head in which at least parts 32a, 32b of magnetic layers are composed of Co-Nb-Zr amorphous magnetic alloy, the Co-Nb-Zr amorphous magnetic alloy contains (80.0+x) at% of Co, [(12.8-16.8)-0.7x] at% of Nb and [(3.2-7,2)-0.3x] at% of Zr, where 0<=x<=10, 80<=Co<=90 (at%). When the composition of the Co-Nb-Zr amorphous alloy contains in the above ranges, decrease in the magnetic properties of the head becomes an allowable range.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic head at least partially composed of a Co--Nb--Zr amorphous magnetic alloy.

(Conventional technology) In order to support high-density magnetic recording, the main G.C.

A magnetic head in which the magnetic layer force is formed by an Nb-Zr amorphous magnetic alloy has been put into practical use. As an example, the present inventors considered a core base portion whose side surface facing the magnetic gap is inclined with respect to the magnetic gap plane, and a side surface of the core base portion facing the magnetic gap. proposed a magnetic head using a magnetic heald core with a magnetic thin film mainly made of an amorphous magnetic alloy of Co--Nb--Zr (Japanese Patent Laid-Open No. 58155513).

FIG. 4 is a perspective view showing the magnetic head, with La, l
b is a half magnetic core made of a magnetic ferrite substrate, 2a,
2b is a magnetic layer mainly made of Co-Nb-Zr amorphous magnetic alloy, 3 is a protective film for protecting the magnetic layer from erosion of glass 4, 4 is glass, 5 is a magnetic gap, and 6 is a wire-wound window. be.

Hereinafter, an example of a method for manufacturing this magnetic head will be explained based on FIGS. 5 to 8. In FIG. 5, grooves 7.7 are provided in parallel in close proximity to each other on one side of the ferrite block 1 constituting the magnetic helad core halves 1a, 1b, and protrusions 8 are formed between the grooves 7.

Next, on the surface on which the grooves 7 and protrusions 8 are formed, a magnetic layer 2 mainly made of a Co-Nb-Zr amorphous magnetic alloy and a protective film 3 made of 5iOz are formed using a thin film manufacturing technique such as sputtering. . Next, as shown in FIG. 6, the glass 4 is provided relatively thickly, and then polished to the position shown by the dotted line in the figure. A portion of the magnetic film 2 formed at the tip of the protrusion 8 is polished flat to form a flat portion 9, and a magnetic gap is formed in this portion.

As shown in FIG. 7, some of the blocks formed in this manner have winding grooves 10 perpendicular to the protrusions 8 formed at a predetermined depth, thereby having winding grooves 6. This becomes the magnetic helad core half body 1b.

Next, as shown in FIG. 8, these two head core halves are joined together by a glass bonding process in which they are heated and pressed so that the glasses 4 face each other. At this time, in order to obtain a predetermined magnetic gap length, a gap regulating film made of SiO□ with a predetermined thickness is formed on the bonding surface of each of the two magnetic helad core halves 1a and 1b by a physical process such as sputtering. Formed by vapor deposition.

Finally, by cutting this joined block along the dotted line in the figure, the magnetic head shown in FIG. 4 is obtained.

By the way, RF2F2 type sputtering equipment and planar magnetron sputtering equipment are currently often used to create Co--Nb--Zr amorphous magnetic films. In particular, planar magnetron sputtering equipment has been widely used in recent years because of its high film formation rate. This device is an RF2F2 type target device in which a magnet for plasma convergence is provided below the target.

Conventionally, permanent magnets have often been used for this magnet, but
Recently, planar magnetron sputtering devices using electromagnets have also begun to be used in order to effectively utilize targets and obtain uniform film thickness distribution.

FIG. 9 is a sectional view of an anode electrode of a planar magnetron sputtering apparatus using this electromagnet. In FIG. 9, 21 is a yoke, 22 is an inner coil, 23 is an outer coil, 24 is a target, 25 is a backing plate,
26 is the backing plate reinforcement plate, 27 is the 0 ring, 2
8 is an earth shield, 29 is an insulating material, and 30 is an outer wall of the vacuum chamber.

Inner coil 22 and outer coil 23 wound around yoke 21
By passing an appropriate direct current through the target, erosion areas C and D appearing at the center and outer periphery of the target are alternately sputtered as shown in Figure 10, thereby achieving effective use of the target and uniform film thickness distribution. It looks like this.

[Problem to be Solved by the Invention] However, in such a case, depending on the magnitude and period of the current flowing through the electromagnet and the positional relationship between the magnetic head substrate and the target, it is possible to obtain the erosion region C at the center by sputtering. The composition of the film is different from that of the film obtained by sputtering the outer peripheral erosion region. That is, in the 11th session, white ○ indicates the composition of the film obtained by sputtering the erosion region at the center of the target, and black O indicates the composition of the film obtained by sputtering the erosion region at the outer periphery of the target. ing. If the composition of the erosion region in the central part differs from that in the outer peripheral part of the magnetic film, depending on the degree of compositional modulation in the depth direction, a magnetic film with predetermined magnetic properties cannot be obtained, and the magnetic head This was a cause of deterioration in the recording and reproducing characteristics of.

An object of the present invention is to provide a magnetic layer in which at least a portion of the magnetic layer is made of Co--Nb.
- It is an object of the present invention to provide a magnetic head made of a Zr amorphous magnetic alloy, in which a magnetic film with predetermined magnetic properties can be obtained and recording and reproducing characteristics can be improved.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a magnetic head in which at least a part of the magnetic layer is made of a Co-Nb-Zr amorphous magnetic alloy.
Amorphous n-type alloy Co: (80,0+x)at% Nb: [(12,8~16.8)-0,7x)at
%Z': [(3,2~7.2)-0,3x)a
t% However, 0≦x≦10.80≦Co≦90 (at%)
This is a magnetic head characterized by comprising:

That is, it was determined that as long as the composition of the Co--Nb--Zr amorphous alloy was within the above-mentioned range, the deterioration of the magnetic properties of the magnetic head would be within an acceptable range.

In order not to deteriorate the magnetic properties of the magnetic head, magnetostriction ±
It is necessary to satisfy 5×101.

(80,0+X)Co-(12,8-0,7x)N
b - (5,2-0,3x)Zr (at%)...
...(1) The above formula (1) is a formula showing magnetostriction ±0 in the Co-Nb-Zr amorphous alloy.

(80,0+x)Co-(13,8-0,7x)N
b - (7,2-0,3x)Zr (at%)...
- (2) Moreover, the formula (2) is a formula indicating a composition with magnetostriction of +5×10 to 1.

(80,0+x)Co-(16,8-0,7x)Nb
-(3,2-0,3x)Zr(at%)...
(3) Furthermore, formula (3) is a formula representing a composition with a brush strain of -5X 10-'. However, in formulas (1) to (3), 0≦x≦10.80≦Co≦90 (at%). Therefore, the compositions included in these ranges are Co: (80,0+x) at %Nb: [
(12,8~16.8)-0,7x)at%Zr
: [(3,2~7.2)-0,3x)a t%
In this case, deterioration of the magnetic properties of the magnetic head is prevented.

FIG. 2 shows the relationship between relative output and recording density when the compositional modulation width falls within this range (A) and when it does not (B). In the case of (A), the film composition is centered on the composition represented by the above formula (1), and the composition is modulated within the range represented by the formula (4).

In the case of method (B), the film composition is similarly centered around the composition represented by the above formula (1), and the composition is modulated within the range represented by formula (5).

(4) (80,0+ x)Co − [(13,8±1
．． 0)-0,7xl Nb[(5,2±1.0)-0,
3x) ) Zr (at%) (5) (80,0+
x) Go - [(12,8±2.5)-0,1x3Nb
[(5,2±2.5) 0.3x) Zr (at
%) (0≦x≦10) It can be seen that the relative output of (A) is about 3 dB higher than that of (B). This is because (B) has a large compositional modulation width with respect to the central composition, so the magnetostriction becomes too large, and due to the stress on the film, the uniaxial magnetic anisotropy of the magnetic film does not go in the predetermined direction. This is probably due to a large decrease in magnetic permeability. On the other hand, in (A), the width of the compositional modulation is small, so the magnetostriction is also small, and it is difficult to be affected by stress, which is considered to be the reason for the large relative output.

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

FIG. 1 is a perspective view of a magnetic head according to the present invention, 31
a and 31b are magnetic ferrite substrates, 32a and 32b are magnetic layers mainly made of a Co-Nb-Zr amorphous magnetic alloy, and 3
3 is a protective film for protecting these magnetic layers from glass 34;
34 is glass, 35 is a magnetic gap, and 36 is a winding window. The manufacturing method of this magnetic head is the same as that described in FIGS. 5 to 8 except for the sputtering conditions when producing the Co--Nb--Zr amorphous magnetic winding.

Next, the sputtering conditions for Co-Nb-Zr amorphous winding were changed to the first
Shown in the table.

Table 1 The magnetron electromagnet current is as follows: 4A current is constantly passed through the inner coil 22, 4A current of opposite polarity is passed through the outer coil 23 for 4.5 seconds, the current is set to OA in 0.5 seconds, and then 4.
Hold at OA for 5 seconds, then go back to 4A for 0.5 seconds.

In other words, a current of OA and 4A is applied only to the outer coil 23 at a cycle of 10 seconds.

The composition of the film thus obtained is shown in FIG. 3 by circles.

Then, in order to observe the compositional modulation in the depth direction, the outer coil 23
The composition of the obtained film was eroded only at the center of the target by not periodically changing the current flowing through the outer coil 23, and by passing a current of 4 A through the outer coil 23. The composition of the film obtained by eroding only the part is shown below.

From this, by adopting the sputtering conditions in Table 1,
The Co-Nb-Zr amorphous alloy in this example is the above-mentioned (1
It can be seen that the composition is modulated within the range expressed by (6) 2, centered on the composition expressed by formula (6).

〔Effect of the invention〕

As explained above, according to the present invention, Co-Nb sputtering is performed using a planar magnetron sputtering apparatus using an electromagnet.
By defining the width of the compositional modulation in the depth direction when creating the -Zr amorphous magnetic alloy, it was possible to obtain a magnetic head with good recording and reproducing characteristics.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a magnetic head according to the present invention, and Fig. 2 shows the relationship between relative output and recording density of a magnetic head having a Co-Nb-Zr amorphous alloy composition of the present invention and a magnetic head of a comparative example. 3 is a film composition diagram, FIG. 4 is a perspective view of a magnetic head according to the prior art, FIGS. 5, 6, 7,
Fig. 8 is an explanatory diagram of the manufacturing method, Fig. 9 is a cross-sectional view of a planar magnetron electrode using an electromagnet, and Fig. 1
FIG. 0 is an explanatory diagram showing the erosion region appearing on the target, and FIG. 11 is a composition diagram showing the difference in film composition when the erosion region is different. 31a, 31b...Magnetic ferrite base, 32
a, 32b...Magnetic layer (Co-Nb-Zr amorphous alloy), 33...Protective film, 34...
Glass, 35...Magnetic gap, 36...
...Window window. Fig. 2 Fig. 1 Recording density 1 truth (Ki C1) Fig. 4 Fig. 8 Fig. ? Figure 1O

Claims (1)

[Claims] 1) A magnetic head in which at least a part of the magnetic layer is made of a Co-Nb-Zr amorphous magnetic alloy, in which the C
The o-Nb-Zr amorphous magnetic alloy is Co:(80.0+x
)at% Nb: [(12.8-16.8)-0.7x]at%Z
r: [(3.2-7.2)-0.3x] at% However, 0
A magnetic head characterized in that ≦x≦10, 80≦Co≦90 (at%).