JPS59101024A - Magnetic head - Google Patents

Abstract

PURPOSE:To reduce high speed abrasion, deterioration of output of a metallic tape due to its use and spontaneous deterioration of reproduction output in a high frequency region after storage at high temp. and high humidity by forming a thin amorphous magnetic alloy film made of Co-Zr-Ru type on a substrate. CONSTITUTION:A 30mum thin film of an amorphous magnetic alloy represented by formula I and ''Sendust'' is formed on a 2mm. thick alumina substrate by sputtering. It is ground and polished to obtain the half bodies 1, 1' of cores, and they are brought into contact with each other by interposing a 0.3mm. thick front gap material of silica, and a prescribed coil 8 is wound around them to prepare a magnetic head. In formula I , T is Co alone or a combination of Co and at least one of transition metals except Co, Zr, Ru and group VI B elements; X is Zr alone or a combination of one of other glass forming elements; M is at least one kind of element of group VIB; and x+y+z+w=100at%, y=5-30at%, z<=8at%, and w<=10at%.

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 magnetic head materials because they exhibit high saturation magnetization and high magnetic permeability.

In order to form a narrow magnetic head with track 11 from an amorphous magnetic alloy thin plate, for example, a rotary head for video recording, recording/playback or audio, or a magnetic head for a computer, the thin plate may be used as is, or A plurality of these sheets are laminated to form half-core cores of a predetermined shape with a track width of several tens of gm or less, particularly about 20 to 30 gm, with a gap interposed therebetween.

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

Furthermore, since the thin plate of amorphous magnetic alloy has high elasticity, it deforms as it slides at high speed with the video magnetic recording medium, causing the head arm to become unbalanced and 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 the magnetic head formed in this manner, the above-mentioned disadvantages are eliminated.

By the way, Co--Zr is known as a sputtering thin film of an amorphous magnetic alloy. However, Co-Zr
When forming a magnetic head by forming a sputtered thin film, there is a drawback that the amount of wear caused by the high-speed movement with the magnetic recording medium is large.

Furthermore, when using a coating type medium using alloy magnetic powder, such as a so-called metal tape, there is a drawback that the thin film becomes colored as it is used, resulting in a decrease in output.

In view of these actual circumstances, the present inventors first developed Co-Z
It is proposed that an r-Ru based amorphous sputtered thin film be used as a magnetic head.

However, when this head is stored under high temperature and high humidity,
The drawback is that an oxide film is formed on the surface of the thin film, increasing spacing loss and reducing self-recording/reproducing output, especially in the high frequency range.

II. Purpose of the Invention The present invention was developed in view of the above-mentioned circumstances, and its main purpose is to reduce the amount of wear at high speeds, reduce the output drop due to the use of metal tape, and also reduce storage under high temperature and high humidity conditions. It is an object of the present invention to provide a magnetic head having an amorphous magnetic alloy thin film in which the self-recording/reproducing output in the high frequency range is less degraded.

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 % Formula % (In the above formula, T is Co, or Co and Co, Zr, R
represents a combination of u and one or more transition metal elements other than group VIB elements, X represents Zr, or a combination of Zr and one or more other vitrification elements, and M is Represents one or more VIB group elements, x+y+z+
W = 100at%, of which y is 5 to 30a
t%, 2 is 8 at% or less, and W is 10 at% 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 in an amorphous state with substantially no long-range regularity.

The composition is shown by the above formula.

In the above formula, other additive elements added in combination with CO as necessary in T are CO, Zr, and Ru.
and other transition metal elements other than group VIB elements (5c-Z
n; Y-Cd; La"Hg; Ac or more), such as Fe, Ni, Ti, Hf, Mn, Rh, Pd, Os, I
Specific examples include one or more of r, Pt, and the like.

On the other hand, X is preferably Zr alone or a combination of Zr and one or more other vitrifying elements.

In this case, preferred examples of other vitrifying elements added in combination with Zr as needed include one or more of Si, B, and the like.

Furthermore, in the composition of the present invention, Ru is an essential component.

In this case, Ru may be replaced with other platinum group metal elements, such as Pt, R
If the tape is changed to H or the like, the effects of excellent high-speed abrasion resistance and little output drop when using a metal tape will not be achieved.

In addition, the composition of the present invention contains Vl, group B elements (Cr,
Mo, W) (7) One or more types of M are contained.

In this case, if the VIB group element is not included or if other elements are used, the desired effects of the present invention will not be achieved.

On the other hand, in the above formula, x+y+z+w=100
Under the condition of at%, the Ru addition amount 2 is 8 at% or less.

This is because if it exceeds 8 at%, it becomes difficult to become amorphous and the adhesive strength with the substrate decreases.

In this case, if the Ru addition amount 2 is small, the desired effect of the present invention will not be effective, so Z is preferably 0.5 to 6 at%, more preferably 1 to 5 at%.

On the other hand, the vitrification element component X which has Zr as an essential component
The addition amount y is 5 to 30 at%.

If y is less than 5 at%, it will be difficult to make it amorphous, and if y is more than 30 at%, sufficient saturation magnetic flux density will not be obtained.

In this case, more preferable results are obtained when y is 5 to 20 at%.

Further, the amount W added of M is 10 at % or less.

When W exceeds 1 oat%, the saturation magnetic flux density becomes as small as 0.6 T or less, making it unsuitable for recording on a high coercive force medium.

However, if W becomes small, the effect of preventing deterioration due to storage under high temperature and high humidity becomes ineffective, so W is preferably 0.5% or more.

In particular, W is 0.5 to 6%, more preferably 1 to 6%.
Even more favorable results are obtained at 6%.

Note that the T content X is 1100-y-z-,
It is preferably 75 to 85 at%.

In this case, T contains Co as an essential component.

As mentioned above, T can be composed of Co and one or more transition metal elements other than C01Ru, Zr, and VIB group elements, but one or more of the other transition metal elements are
Usually, the total content can be up to 10 at%.

If the content exceeds this range, problems such as a decrease in the saturation magnetic flux density Bs will occur.

One example of such an element is Fe.

Addition of Fe has the effect of lowering magnetostriction, but as the amount of Fe increases, magnetostriction increases and magnetic properties deteriorate due to the influence of processing strain, so the Fe content should be 6 at% or less. preferable.

Further, Ni can also be added to T. Ni
Addition has the effect of replacing Co and reducing material cost I. However, as the amount of Ni increases, Bs decreases, so the Ni content is preferably 10 at % or less.

Furthermore, as described above, Mn or the like can also be added.

However, rather than something like this, it is usually better to
It is preferable that it be used alone.

On the other hand, the vitrification element component X has Zr as an essential component.

Usually, X consists only of Zr, but X consists of the above-mentioned B, S
It may be a combination of one or more types such as i etc. in a total amount of 10 at % or less and Zr.

The amorphous magnetic alloy thin film having such a composition is deposited on the substrate in an amount of approximately 0.001 m to 100 g, preferably 20 to 50 g.
It is formed to have a thickness of about 1.0 m.

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, silicides, nitrides, glasses, etc. can be suitably used.

The substrate material may be appropriately selected and used in consideration of the physical properties of the amorphous magnetic alloy thin film, workability, slidability with the medium, and the like.

There are no particular restrictions on the thickness of such a substrate, but
Usually, it is about 0.1 to 5 mm.

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

The sputtering used is to sputter a target using bombarded ions, usually at several eV to about 100 eV.
Any known sputtering method that evaporates the target material with a kinetic energy on the order of V can be used.

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 inert gas atmosphere such as Ar,
An ion beam method in which ion beams such as , Xe, etc. are irradiated may be used.

When using a plasma method, it may be so-called RF sputtering or so-called DC sputtering,
The device configuration may be either 2-pole, 4-pole, etc.
Furthermore, so-called magnetron sputtering may be used. 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 substrate 2.2' on which the amorphous magnetic alloy thin film 3.3' is formed is processed into a predetermined shape, such as a 1-shape, a C-shape, etc., as shown in FIGS. 1 and 2. Core half of 1.1
', and are brought together to form the magnetic head 1 through a cap material 40 such as SIO2 at the front gear, pull section 4, and rear gap section.

Note that on the thin film 3.3' of the core half 1.1', 1. Furthermore, a protective body 5 made of the same material as the base body 2.2' can also be adhered.

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

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

Then, winding 8 is applied, alignment is performed as described above, and other necessary processing is performed, and the magnetic head is fixed to a support 9 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., or a magnetic head for computers.

Furthermore, the magnetic head of the present invention suffers 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.

Furthermore, there is little formation of a surface oxide film after storage under high temperature and high humidity conditions, and the decrease in self-recording/reproducing output due to spacing and loss is extremely small.

And, such an effect is caused by a predetermined amount of Ru and VIB.
This is achieved only when group elements are added.

(2) Specific Examples of the Invention Hereinafter, specific examples of the present invention will be shown and the present invention will be explained in more detail.

Example 3071 thin films of each amorphous magnetic alloy and sendust having the compositions shown in Table 1 below were deposited on a 2 mm thick alumina substrate.
It was formed to have a thickness of m.

The thin film was formed by sputtering.

In this case, a cast body of an alloy with a corresponding composition is used as a target, and an operating argon pressure of 5,5 X I 0-
3Torr, plate voltage 2KV, input power 4W/
RF magnetron sputtering was performed at Cm'.

Next, this was ground and polished to obtain core halves l, 1' as shown in Figs.
The front gap material of pm is brought together via SiO2,
A predetermined winding 8 was applied to produce a magnetic head.

Next, each magnetic head was mounted on an 8 mm video deck, and the following measurements 1) and 2) were performed.

1) Abrasion amount At 25°C and 150%RH, apply 3 coated metal tape.
．． It was run at 75 m/see for 100 hours, and the amount of wear after running was measured using a surface roughness meter. The results are shown in Table 1 as relative values, assuming that the amount of wear in the case of Sendust is 10.
Shown below.

2) Decrease in output of 5MHz signal At 25°C, 550%RH, apply coated metal tape to
．． A short run was made for 4 hours at 75 m/sec, and the decrease in output after the run was measured.

The results are shown in Table 1.

3) Self-recorded reappearance after storage under high temperature and high humidity conditions (low 40°C1)
After storage for 240 hours at relative humidity 90-95%, coercive force 1
The self-recording/reproducing output was measured using a coated metal tape of 5000e, and the output drop (dB) 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 drawings]

1 and 2 show one example of the structure of the magnetic head of the present invention.
1 is a perspective view, and FIG. 2 is an enlarged partial front view. 1.1'...Core half-break 2.2'...Substrate 3.3'...Amorphous magnetic alloy thin film Applicant Tokyo Denki Kagaku Kogyo Co., Ltd. Agent Patent attorney Mr. Yo Ishii - 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 % Formula % (In the above formula, T is Co, or co, l!: co, Z
r, Ru and one or more transition metal elements other than group VIB elements, and X is Zr or Z
represents a combination of r and one or more other vitrifying elements, M represents one or more VIB group elements, x+y+z+
W=100at%, of which y is 5 to 30at%
%, Z is 8 at% or less, and W is 10 at% or less. 2. The magnetic head according to claim 1, wherein T is made of Co. 3. The magnetic head according to claim 1 or 2, wherein X is composed of Zr or a combination of Zr and at least 10 at % in total of one or more of B and Si. 4. The magnetic head according to any one of paragraphs 1 to 3 of the first range of patent H1'i, wherein Y is 5 to 20 at%. 5. The magnetic head according to claim 1, wherein z is 0.5 to 6 at%. 6. The magnetic head according to any one of claims 1 to 5, wherein w is 0.5 to 6 at%. 7. The magnetic head according to any one of claims 1 to 6, wherein the thin film has a thickness of 0.1-100 pm. 8. A magnetic head according to any one of claims 1 to 7, wherein the base is nonmagnetic.