JPS58224425A - Magnetic head - Google Patents

Abstract

PURPOSE:To obtain a magnetic head small in abrasion amt. due to high speed sliding and also deterioration of output due to the use of a metallic tape, and good in storage stability in high temp. and high humidity, by forming an amorphous magnetic thin alloy film having a specified compsn. on a base. CONSTITUTION:The amorphous magnetic thin alloy films 4, 4' are formed on bases 3, 3' using a cast alloy having the formula as shown to form core bodies 2, 2', and they are butted to each other, interposing each gap material SiO2 6, 7 in a front gap 11 and a back gap 13, respectively, and a wire is coiled to manufacture a magnetic tape. In the formula, T is Co, a combination of Co and Fe, or a combination of Co, Fe and at least one kind of transition metals, such as Ni, Mn, and Os; X is B, a combination of B and Si, or a combination of B, Si, and another glass-forming element, such as P, C, Ge, Sn, or Al; x+y+z= 100at%, y is 16-35at%, z is <=8at%; and Fe is 0.1-6at%, and Co is >=50at%. The magnetic head thus obtained is small in an amt. of abrasion due to contact with a metallic tape, and good in storage stability even in high temp. and high humidity.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Background of the Invention Technical Field The present invention relates to a magnetic head. More specifically, the present invention relates to a magnetic head having an amorphous magnetic alloy thin film.

Prior art and its problems Thin sheets of amorphous magnetic alloys have attracted attention as mishead materials because they exhibit high saturation magnetization and high magnetic permeability.

Narrow magnetic heads in tracks, for example, rotating heads for video recording, recording/playback or audio, magnetic heads for computers, etc., are formed from amorphous magnetic alloy thin sheets (thin sheets). is used as it is, or a plurality of them are laminated to form a track with a thickness of several tens of micrometers or less, especially about 20 to 30 micrometers, and half cores of a predetermined shape are made by butting them together through a gap. .

However, heads for videos and the like manufactured in this manner are extremely thin and therefore do not have sufficient strength, are deformed by mechanical processing, and have the disadvantage of poor dimensional accuracy after processing.

In addition, since the thin plate of amorphous magnetic alloy is highly elastic, it deforms when sliding at high speed with the magnetic recording medium for video.
The head arm becomes unbalanced, resulting in poor rotational running performance.

In order to eliminate such inconveniences, it is conceivable to form a thin film of an amorphous magnetic alloy on the substrate by sputtering to make the core half-closed, and then form a magnetic head from this.

In such a magnetic head, the above-mentioned disadvantages can be solved.

However, when forming an amorphous magnetic alloy thin film with a normal composition, there is a drawback that the amount of wear caused by high-speed sliding with a magnetic recording medium is large.

Also, when using a coating type medium using alloy magnetic powder, such as a so-called metal tape.

The disadvantage is that the thin film becomes colored as it is used, resulting in a decrease in output.

In view of this situation, the present inventors have previously proposed the use of an amorphous magnetic alloy thin film containing Ru.

In such a case, high speed wear t is reduced.

Output reduction due to the use of metal tape is reduced.

However, there is a drawback that the single frequency characteristic (f characteristic) deteriorates due to storage under high temperature and high humidity conditions.

■ Purpose of the Invention The present invention was made in view of the above-mentioned circumstances, and its main purpose is to create an amorphous material that has less high-speed wear, less output loss due to the use of metal tape, and has good storage stability. An object of the present invention is to provide a magnetic head having a magnetic alloy thin film.

The present inventors have conducted intensive research for such purposes,
The present invention has been accomplished.

That is, the present invention is a magnetic head characterized in that an amorphous magnetic alloy thin film having a composition represented by the following formula is formed on a substrate.

Formula T X X y a u 2Cr w (in the above formula,
T represents CO1CO and Fe, or a combination with one or more of CO1 or other transition metal sulfide groups such as CO and Fe.

x y ± z w = 100 at%, of which y is 16 to 35 at%, 2 is 8 at% or less, and W is Sat% or less. ) ■Specific structure of the invention The specific structure of the present invention will be explained in detail below.

The thin film in the present invention is substantially in an amorphous state with no long-range regularity.

The composition is shown by the above formula.

In the above formula, in T, if necessary, Co or other additive elements added in combination with Fe and CO are transition metal elements other than Fe and Co and Ru (Sc-Zn; Y% Cd; La-H
f ; Ac or higher), for example, N1, Mn, R
Specific examples include one or more of H, Pd, Os, Ir, and Pt.

On the other hand, X is B, Si and B1 or B or Si
A combination of B and one or more other vitrification elements is preferred.

In this case, an example of other vitrifying elements that may be added as necessary in combination with B or Sl and B is:
One or more types of P, C, Ge, Sn, At, etc. can be mentioned.

Furthermore, in the composition of the present invention, Ru and C
Let r be an essential component.

In this case, Ru may be replaced with other platinum group metal elements, such as Pt, R
When changing to h etc., or replacing Cr with other transition metal elements,
For example, when the material is changed to Mo, W, ■, Nb, Ta, Ti, Zr, etc., the desired effects of the present invention will not be achieved.

On the other hand, in the above formula, x+y+z+W=10Q
Under the condition of at%, Ru addition -Ikz is 8 at% or less.

When the content exceeds 8 at%, it becomes difficult to become amorphous, and conversely, high-speed wear resistance etc. decrease.

This is because the use of a metal tape causes a large decrease in output.

In this case, if Ru addition i'z is small, these effects will be lost, so 2 is preferably 0.5 to 5 at%, more preferably 0.5 to 5 at%.

On the other hand, C'addition amount W&'! is 13 at% or less.

When it exceeds 8 at%, it becomes difficult to become amorphous.

Moreover, on the contrary, the storage stability, etc., especially under high temperature and high humidity conditions, deteriorates.

In this case, if the amount W of Or added is small, these effects will not be effective, so it is preferable that W is 0.5 to 6 at%, more preferably 05 to 5 at%.

On the other hand, the amount y of the vitrification element component X added is 16 to 3
It is 5at%.

When y is less than 16 at%, it becomes difficult to make it amorphous,
Moreover, when y exceeds 35 at%, sufficient saturation magnetic flux density cannot be obtained.

In this case, more preferable results are obtained when y is 18 to 30 at%.

The content X of 'r above is 100-Y-Z-W, which is 48 at% or more and less than 84 at%, but 48 to
Preferably, it is 83 at%.

In this case, T includes Co or CO and Fe.

The elemental composition ratio in T is selected so that the magnetostriction is close to zero.

Therefore, the Fe content is usually 0 or 6 at% or less. When the Pe content exceeds 6 at %, magnetostriction increases, and magnetic permeability decreases due to various stresses in the magnetic head manufacturing process.

Note that T contains Fe, and the Fe content is 0.1 to 5.
At %, more preferably i2 to 5 at %, more favorable results can be obtained in terms of magnetostriction.

On the other hand, the Co content is preferably 50a1% or more. If the Co content is less than 50 at%, the saturation magnetic flux density Bs will decrease.

Furthermore, as mentioned above, within the above content range, T may consist of only COl or Fe and CO;
It may consist of Ol or Fe and CO and one or more of the other elements mentioned above.

T, Co or Fe and CO plus one of the other elements
When more than one species is included, one or more of the other transition metal elements can usually be contained up to a maximum of 10 at% in total.
If the content exceeds this range, Bs decreases, causing problems such as deterioration of abrasion resistance, metal tape compatibility, and storage stability.

An example of such an element is Ni.

The addition of N1 has the effect of replacing Co and reducing material costs, but as lNi1L- increases, Bs decreases, so the Nj content is preferably 8 at% or less.

However, one or more of these other transition metal elements may be present.
The total amount is preferably 10 at% or less. At this time, the decrease in Bs is small and effects unique to each addition are realized.

Suitable examples of such elements include Mn and the like.

On the other hand, the vitrification element component X has B or Si and B as essential components.

In this case, when the B content is 16 to 35 at% and the Si content is 0 to 6 at%, Bs becomes high, and the wear resistance and
Metal tape compatibility and storage stability are improved to obtain favorable results.

When the 8th row content is 15.2 to 24 at% and the Sr content is 0.1 to 48 at%, Bs becomes even higher, and wear resistance, metal tape compatibility, and storage stability are further improved. Get favorable results.

In such a case, the Si 2 /(Si 1 B ) ratio (atomic ratio) in X is preferably 0 or 0.02 or less.

When the Si/(Si + B) ratio] becomes 0.2 or less,
High-speed wear becomes extremely small, output decrease due to the use of metal tape becomes extremely small, and f% deterioration due to storage under high temperature and high humidity becomes extremely small.

Further, when the ratio/(81+B) is 0.05 to 0.15, even more favorable results can be obtained.

Note that the vitrification principal component X may contain one or more elements other than Si and B, if necessary. However, if the total amount exceeds 0.5 at%, it becomes difficult to form amorphous, so the content is preferably 0.5 at% or less.

An amorphous magnetic alloy thin film having such a composition is formed on a substrate to a thickness of approximately 0.1 to 100 μm, particularly 1 to 100 μm.

The substrate used is usually non-magnetic.

In this case, there are no particular restrictions on the material of the base.

Therefore, any of various oxides, carbides, nitrides, silicides, glasses, etc. can be used, and should be selected as appropriate, taking into consideration the physical properties of the amorphous magnetic alloy thin film, workability, slidability with the medium, etc. Just use it.

There are no particular restrictions on the thickness of such a substrate, but
Usually, it is about 01 to 5 mm.

A vapor phase deposition method, usually sputtering, is used to form an amorphous magnetic alloy thin film on such a substrate.

As the sputtering method used, any known sputtering method can be used, in which a target is sputtered by bombarded ions and the target material is usually evaporated with a kinetic energy of several eV to about 100 eV.

Therefore, even if a plasma method is used in which the target is sputtered with ions such as Ar caused by abnormal glow discharge in an atmosphere of an inert gas such as Ar, Kr, or Xe, the target will not contain Ar or Kr.

An ion beam method using a neutral ion beam such as Xe may also be used.

When using the plasma method, it may be so-called IT F sputtering or so-called DC sputtering, and the method Wt#! The configuration may also be bipolar, quadrupolar, etc. Furthermore.

It is also possible to use magnetron sputtering. In some cases, so-called reactive sputtering may also be used. Furthermore, various methods can be used as the ion beam method.

In normal cases, a master alloy having a corresponding composition may be used as the target.

Note that there are no particular restrictions on the operating pressure, plate voltage, plate current, gap between electrodes, etc., and these can be set to arbitrary values depending on the conditions.

In such a case, an underlayer may be formed on one surface of the substrate, and an amorphous magnetic alloy thin film may be formed on this underlayer.
Further, an upper protective layer may be formed on the amorphous magnetic alloy thin film.

Furthermore, amorphous magnetic alloy thin films and non-magnetic thin films can be alternately laminated.

The substrates 3, 3' on which the amorphous magnetic alloy thin film 4.4' is formed are processed into a predetermined shape, such as a 1-shape, a C-shape, etc., as shown in FIGS. 1 and 2. core half-day break 2.2
', and are brought together at the front gap tlJit and the rear gap part 13 via a gap material 6.7, such as SiO□, to form the magnetic head 1.

Furthermore, on the core half-hole 2.2', there is also a base body 3.3'.
A protector made of the same material can also be attached.

In such a case, after forming the thin film, heat treatment is performed in a non-magnetic field or in a static or rotating magnetic field, if necessary.

Next, it is ground to a predetermined shape, and if necessary, it is ground to a predetermined film thickness, and if necessary, it is further polished to make the core semi-dry.

Then, winding is performed, alignment is performed as described above, and other necessary processing is performed to produce a magnetic head.

Note that the above heat treatment may be performed after shape processing and before winding.

(2) Specific effects of the invention Such a magnetic head is extremely useful as a rotary head for video recording, recording/playback, audio, etc., a magnetic head for computers, and the like.

The magnetic head of the present invention has extremely little wear due to high-speed sliding of the medium.

In addition, there is very little reduction in output due to the use of coated media such as metal tapes that use alloyed magnetic powder.

In addition, there is very little deterioration even under high temperature and high humidity conditions.

These effects are achieved only when Ru and Cr are contained in predetermined amounts.

(1) Specific Examples of the Invention One specific example of the present invention will be shown below to explain the present invention in further detail.

Example 2 Thin films of each amorphous magnetic alloy and sendust having the compositions shown in Table 1 below were formed to a thickness of 30 μm on an alumina substrate having a thickness of 30 μm.

The thin film was formed by sputtering.

In this case, a cast alloy of the corresponding composition was used as the target, and an operating argon pressure of 5.5×10” Tor
r, plate! [At 2KV, input power 4W/-,
ILF magnetron sputtering was performed.

Next, this was ground and @thickened to obtain a core half-hole 2.2' as shown in Figs. 1 and 2.
They were brought together via a gap material 5I02 and wound in a predetermined manner to produce various magnetic heads.

Next, each magnetic head was mounted on an 8-dark video deck, and the following measurements were performed.

1) Amount of wear (μm) At 25°C and 50% RH, coated metal tape was applied to 4.
It was run at 75 m/sec for 100 hours, and the zero wear amount after running was measured using a surface roughness meter. The amount of wear when milled rice is Sendust is assumed to be 1, and Table 1 shows relative values to this.

2) Output drop (dB) of 5 MHz signal At 25° C. and 50% f-LH, a coated metal tape was run for 4 hours at 4.75 m/sec, and the output drop after running was measured.

The results are shown in Table 1.

3) 1% change after storage After storage at 70° C. and 95% FLH for 240 hours, the change in f at 0.5 MHz (dB) from before storage was measured.

The results are shown in Table 1.

From the results shown in Table 1, the effects of the present invention are clear.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an example of the structure of the magnetic head of the present invention, and FIG. 2 is a right side view of FIG. 1. 1・・・・・・・・・・・・・・・・・・Magnetic head 2.2′・・・・・・・・・Core half 3
・・・・・・・・・・・・・・・・・・・・・Base 4・・・・・・・・・・・・・・・・・・・・・Amorphous magnetic alloy Thin film applicant Tokyo Denki Kagaku Kogyo Co., Ltd. Daikonto Masumaku Ju Ishii Hiroshi - (22) 153- Figure 1 Figure 2

Claims (1)

[Claims] 1. A magnetic head characterized by forming an amorphous magnetic alloy thin film having a composition represented by the following formula on a substrate. Formula T xX y Ru z Cr w (in the above formula, T
is C01CO and Fe1 or CO1 or CO
and represents a combination of Fe and lli or more of another transition metal element, X is B, or B and Si, or B or B
and represents a combination of Si and one or more other vitrifying elements. X'+y+Z+W=loOat%, of which y is 16 to 35 at%, 2 is 8 at% or less, and W is 8 at% or less. ) 2. T is CO and Fe, or CO and Fe and one or more other transition metal elements, and the F"e content is 0
．． The magnetic head according to claim 1, wherein the content is 1 to 6 at%. 3 X is B, or B and Sl, or a combination of B or B and Si with one or more other vitrifying elements, and the Sj/(Si + B) ratio in X is 0 or 0
．． 2. The magnetic head according to claim 1 or 2, wherein the magnetic head is 2 or less. 4. Si/(Si + B) ratio in X is 0.05 to 0.
15. The magnetic head according to claim 3, which is No. 15. 5. The magnetic head according to any one of claims 1 to 4, wherein Y is 18 to 3 Qat%. 5. The magnetic head according to any one of claims 1 to 5, wherein z is 0.5 to 5 at%. 7. The magnetic head according to any one of claims 1 to 6, wherein w is 0°5 to 5 at%. 8. 8. The magnetic head according to claim 1, wherein the thin film has a thickness of 01 to 100 μm. 9. The magnetic head according to any one of claims 1 to 8, wherein the base is nonmagnetic and insulating.