JPH11224416A - Magnetic head and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic head which is used for recording and reproducing of a magnetic recording medium with a high-density recorder and has excellent wear resistance and sliding resistance. SOLUTION: An air floating surface 3 of a magnetic head slider 1 is provided with a hard amorphous carbon film 4 contg. hydrogen and contg. at least one kind among elements, such as silicon, iron and aluminum, as a protective film. The content of the hydrogen is specified to >=10 to <=30 atm.% of the entire element constituting the hard amorphous carbon film 4 and the contents of the elements, such as silicon, iron and aluminum, is specified to >=1 to <=10 atm.% of the carbon. The thickness of the hard amorphous carbon film 4 to be formed as the protective film is specified to >=1 to <=30 nm, more preferably <=10 nm in such a manner that the gap between the magnetic head and the magnetic recording medium is made narrow and sliding resistance may be obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head used for recording and reproducing on a magnetic recording medium in a high-density magnetic storage device.

[0002]

2. Description of the Related Art A magnetic storage device is widely used as an external storage device of a computer, and will be used for recording and reproduction of a moving image in the future. The magnetic head is for writing a signal to a magnetic recording medium or reproducing the written signal in a magnetic storage device, and is used for a non-magnetic slider such as ceramics (Al2O3-TiC) made of alumina and titanium carbide. Equipped with elements for recording and reproduction, thin-film magnetic heads using semiconductor manufacturing processes and MR heads using magnetoresistive (MR) elements for high-density recording are currently used. Have been.

The magnetic head is in contact with the magnetic recording medium while the apparatus is stopped, and the magnetic recording medium rotates at a high speed during recording / reproducing, and the magnetic head flies at a constant interval with respect to the magnetic recording medium. -The start / stop (CSS) operation is repeated. In order to stabilize the flying attitude of the magnetic head and keep the distance between the magnetic head and the magnetic recording medium constant, the air flying surface (AB) is provided on the slider.
S) is formed. Therefore, the magnetic recording medium is CS
At the start and stop of the S operation, it contacts and slides with the ABS. Further, the magnetic head may come into contact with the magnetic recording medium at high speed due to some disturbance while flying. In this way, the magnetic recording medium frequently comes into contact with and slides on the magnetic head, causing wear and damage. Therefore, a protective film having a thickness of several tens nm and a lubricating layer having a thickness of several nm are formed on the surface thereof. .

Recently, a proposal has been made to provide a protective film on the ABS of a magnetic head to improve abrasion resistance. The prior art will be described with reference to FIG. For example, in Japanese Patent Application Laid-Open No. 4-364217, a pair of air floating surfaces 3 are formed on one surface of a slider 1 made of a ceramic material so as to protrude and extend in a rail shape. Is formed with a chamfer 5 having a predetermined inclination angle, and gives a flying height to the slider 1 when the opposing magnetic disk plate rotates. On the side surface at the rear end of the air floating surface 3, the detection element 2 for magnetic recording is arranged so as to be exposed to the air floating surface 3. A protective film made of silicon (Si) 6 and amorphous hydrogenated carbon 7 and having a thickness of about 125 Å is provided on the air floating surface 3. In this case, the Si layer 6 has a role as an adhesion layer between the slider 1 and the amorphous hydrogenated carbon 7, and is made of Al2 O3 which is a slider material.
The reason for this is that the adhesion between TiC and amorphous hydrogenated carbon is small and easily peeled off by a slight force. Amorphous hydrogenated carbon is known to have excellent wear resistance and lubricity, and is provided to protect a magnetic recording medium from mechanical damage.

In order to improve the recording density in a magnetic storage device, it is essential to reduce the distance between the magnetic head and the magnetic recording medium during recording / reproducing, that is, to reduce the flying height. Quantity is required. For this reason, it is essential to further reduce the thickness of the magnetic head protective film, and the film thickness is 10 nm or less, preferably 5 nm.
m or less is required.

[0006]

However, in the case of the conventional two-layer structure of the adhesion layer and the carbon film, the substantial thickness of the carbon-based film with respect to the thickness of the protective film is reduced by the thickness of the intermediate layer. Therefore, when the film thickness is 10 nm or less, the carbon-based film for originally protecting the magnetic recording medium becomes extremely thin, and the wear resistance is lost. Further, if the thickness of the protective film is reduced by reducing the thickness of the intermediate layer in order to maintain the thickness of the carbon-based film, the adhesion of the protective film to the slider is reduced, and the protective film is easily peeled off by an external force. Therefore, it is difficult to make the protective film extremely thin with the magnetic head according to the conventional technique, and it is not possible to sufficiently reduce the gap with the magnetic recording medium required for high-density magnetic recording. Further, in the prior art, the step of forming the intermediate layer is required, so that the step of forming the magnetic head is complicated.

An object of the present invention is to provide an ultra-thin protective film having high adhesion and excellent sliding resistance on a sliding surface without providing an intermediate layer, thereby narrowing a gap with a magnetic recording medium. ,
It is an object of the present invention to provide a magnetic head that can support an ultra-high density magnetic storage device.

[0008]

According to the present invention, there is provided a magnetic head comprising a protective film made of a hard amorphous carbon film provided on a slider, wherein the hard amorphous carbon film contains hydrogen, and The slider is characterized by containing an element that easily bonds to carbon or an element that easily diffuses into carbon and easily bonds to a nonmetal element in the slider material.
Here, the protective film made of the hard amorphous carbon film has a thickness of 1 nm or more and 30 nm or less, preferably 10 nm or less so that the gap between the magnetic head and the magnetic recording medium is narrowed and sliding resistance is obtained. is there.

Here, it is desirable that the hydrogen contained in the hard amorphous carbon film is not less than 10 atomic% and not more than 30 atomic% based on all elements, and the element is not less than 1 atomic% and not more than 10 atomic% based on carbon. % Is desirable.

When hydrogen is contained in the hard amorphous carbon film,
The dangling bonds of carbon atoms in the film are terminated with hydrogen, whereby the hardness of the film is improved, and the wear resistance and slidability are improved.

As an element which easily diffuses into carbon, Si is used.
Is mentioned. Since Si forms a Si—C bond with carbon, when Si is contained in the hard amorphous carbon film, the hard amorphous carbon film is chemically bonded to carbon atoms and taken in the network of carbon atoms. Further, since Si easily reacts with oxygen and metal elements, at the interface between the hard amorphous carbon film and the slider, when Si is used as an oxide material as the slider material, it chemically bonds with oxygen or metal elements in the slider material. . Therefore, the hard amorphous carbon film comes to adhere firmly to the slider by containing Si.

The element which easily diffuses into carbon and easily couples with the nonmetal element in the slider material is variously selected depending on the material of the slider. For example, iron (Fe), aluminum (Al) Although is less reactive with carbon than Si, it is easily diffused into carbon and is easily incorporated into a hard amorphous carbon film. The standard enthalpy of formation of Fe and Al oxides is -1000 kJ / m at room temperature.
ol to -1700 kJ / mol.
e and Al easily react with oxygen. Therefore, when an oxide is used as a slider, Fe and Al in the hard amorphous carbon film are chemically bonded to oxygen atoms, and as a result, the hard amorphous carbon film containing Fe and Al adheres firmly to the slider. I will be. Since the hard amorphous carbon film containing the element having the above-mentioned properties adheres firmly to the slider, there is no need to provide an intermediate layer for adhesion. Table 1 shows additive elements that are effective depending on the slider material used.

[0013]

[Table 1] A good conductor such as TiN is not suitable for a head substrate as a substrate to be used.

Since the magnetic head according to the present invention has a very thin protective film made of a hard amorphous carbon film having high hardness and strong adhesion to the slider, the gap with the magnetic recording medium is reduced. Can be used.

[0015]

FIG. 1 is a perspective view of a magnetic head according to an embodiment of the present invention.

A hard amorphous carbon film 4 was formed on the air floating surface 3 of the slider 1 using an Al2O3-TiC sintered body by sputtering a graphite by a high frequency (rf) magnetron sputtering method. As a sputtering gas, a mixed gas of argon gas and hydrogen gas is used.
In order for Al to be contained in the hard amorphous carbon film 4, each pellet was placed on a graphite target and sputtered simultaneously with graphite. The thickness of the hard amorphous carbon film 4 was controlled by the formation time of the film.

The amount of hydrogen contained in the hard amorphous carbon film 4 formed as described above is analyzed by hydrogen forward scattering and Rutherford back scattering. On the other hand, it was confirmed to contain up to 40 atomic% of hydrogen. Further, as a result of the analysis by Auger electron spectroscopy, the hard amorphous carbon film 4 contained S
It was confirmed that the amounts of i, Fe, and Al were controlled by the number and size of the pellets placed on the carbon target.

Changes in the wear resistance and lubricity of the protective film made of a hard amorphous carbon film due to the contents of hydrogen, Si, Fe, and Al are measured by repeating the adhesion measurement and the contact start / stop (CSS) cycle. The coefficient μ was evaluated by the CSS-μ test method. Here, C
In the SS-μ test, a 3.5-inch diameter magnetic recording medium was used, and the contact load of the magnetic head applied to the magnetic recording medium was 8
g, the rotational speed of the magnetic recording medium was 3600 revolutions per minute.

FIG. 3 shows a magnetic head obtained by a CSS cycle when a hard amorphous carbon film containing 5 atomic% of Si and containing 5 atomic% of hydrogen and having a thickness of 5 nm is used as a protective film for the air floating surface of the magnetic head. 4 shows a change in a friction coefficient between magnetic recording media.
After 20,000 CSS cycles, the coefficient of friction is more than twice that at the start of the test. After the test, when the sample surface was observed with a metallurgical microscope, wear marks or peeling marks were observed on both the magnetic recording medium and the magnetic head. FIG. 4 shows a case where a hard amorphous carbon film having a thickness of 5 nm containing 20 atomic% of hydrogen and 5 atomic% of Si is used as a protective film for the air floating surface of the magnetic head.
4 shows a change in a coefficient of friction between a magnetic head and a magnetic recording medium due to a CSS cycle. The coefficient of friction after 20,000 cycles of CSS is about the same as at the start of the test. As a result of observing the sample surface after the test, no damage was recognized on both the magnetic head and the magnetic recording medium. Hydrogen and Si, F contained in the hard amorphous carbon film
e. The relationship between the increase in the friction coefficient due to CSS and the damage of the magnetic head and the magnetic recording medium was examined for the samples in which the amounts of Al and Al were changed. No damage was observed on the magnetic head and the magnetic recording medium in the sample No., but the sample with a friction coefficient after 20,000 times of CSS was 1.5 times or more the value at the start of CSS showed damage. From this, the sliding resistance of the film can be determined from the change in the friction coefficient. The hard amorphous carbon film whose friction coefficient after 20,000 times of CSS is 1.5 times or less of that at the start of CSS has excellent sliding resistance. Is determined to be.

FIG. 5 shows a change in the friction coefficient between the magnetic head and the magnetic recording medium by a CSS test when the hydrogen content of the hard amorphous carbon film having a thickness of 5 nm containing 5 atomic% of Si is changed. The change in the coefficient of friction is represented by the ratio of the coefficient of friction after 20,000 cycles of CSS and the coefficient of friction at the start of the test (the value obtained by dividing the coefficient of friction after the test by the coefficient of friction at the start of the test). When hydrogen is contained, the change in the friction coefficient due to the CCS test becomes small. When the hydrogen content is in the range of 10 at% to 30 at%, the friction coefficient after 20,000 times of CSS is 1.
5 times or less.

FIG. 6 shows a change in a friction coefficient between a magnetic head and a magnetic recording medium by a CSS test when Si is contained in a hard amorphous carbon film having a thickness of 5 nm containing 20 atomic% of hydrogen. The change in the coefficient of friction is represented by the ratio of the coefficient of friction after 20,000 cycles of CSS and the coefficient of friction at the start of the test (the value obtained by dividing the coefficient of friction after the test by the coefficient of friction at the start of the test). When Si is contained, the change in the coefficient of friction by the CSS test becomes small, and when the Si content is 1 atomic% or more and 10 atomic% or less, CSS
The coefficient of friction after 20,000 times is smaller than 1.5 times that at the start of the CSS test. When the metal element is Fe or Al, as in the case where Si is contained, when the content is 1 atomic% or more and 10 atomic% or less, the friction coefficient after 20,000 times of CSS is 1.5 times that at the start of CSS. Smaller than.

From the above, hydrogen contained in the hard amorphous carbon film is not less than 10 atomic% and not more than 30 atomic%, and Si, Fe, Al
Is desirably from 1 atomic% to 10 atomic%.

[0023]

EXAMPLES Table 2 shows the adhesion of the protective film to the magnetic head and the results of evaluation by a CSS test when the thickness of the protective film of the magnetic head was 5 nm. In the determination of the CSS test, a sample in which the friction coefficient was 1.5 times or more that at the start of CSS by 20,000 times of CSS was rejected. The protection film was damaged in the magnetic heads of Comparative Examples 1 and 2 which failed the microscopic observation after the CSS test, and the protection film was peeled off in the magnetic heads of Comparative Examples 3, 5 and 7. , Comparative Example 4, Comparative Example 6,
In the magnetic head of Comparative Example 8, a powdery product was confirmed.

Here, the thickness of the hard amorphous carbon film as the protective film on the air floating surface is 5 nm, but the thickness is 1 nm.
Similar results were obtained when the thickness was reduced to as small as possible. Also, 2
Even if more than one kind of metal element is combined,
Similar results were obtained as for the types.

[0025]

[Table 2]

[0026]

As described above, the magnetic head according to the present invention has a protective film exhibiting excellent sliding resistance without providing an intermediate layer. Therefore, the thickness of the protective film can be reduced as compared with the case where the intermediate layer is provided, and the space between the protective film and the magnetic recording medium can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view of a magnetic head protective film according to the present invention.

FIG. 2 is a perspective view of a conventional magnetic head protection film.

FIG. 3 shows a thickness 5 containing no hydrogen and containing 5 atomic% of Si.
FIG. 7 is a diagram showing a change in a coefficient of friction between a magnetic head and a magnetic recording medium by a CSS cycle when a hard amorphous carbon film having a thickness of nm is used as a magnetic head protective film.

FIG. 4 shows a coefficient of friction between a magnetic head and a magnetic recording medium by a CSS cycle when a hard amorphous carbon film having a thickness of 5 nm containing 20 atomic% of hydrogen and 5 atomic% of Si is used as a magnetic head protective film. FIG.

FIG. 5 shows the amount of change in the coefficient of friction between a magnetic head and a magnetic recording medium due to 20,000 CSS cycles when the hydrogen content of a 5 nm thick hard amorphous carbon film containing 5 atomic% of Si is changed. FIG.

FIG. 6 shows the amount of change in the coefficient of friction between the magnetic head and the magnetic recording medium due to 20,000 times of CSS when the Si content of the 5 nm thick hard amorphous carbon film containing 20 atomic% of hydrogen was changed. FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Magnetic head slider 2 Detecting element 3 Air floating surface 4 Hard amorphous carbon film 5 Chamfer 6 Si layer with a thickness of 1 to 5 nm 7 Amorphous hydrogenated carbon with a thickness of 25 nm or less

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[Procedure amendment]

[Submission date] April 2, 1999

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Name of invention

[Correction method] Change

[Correction contents]

Patent application title: MAGNETIC HEAD AND ITS MANUFACTURING METHOD

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

8. The magnetic head according to claim 1, wherein the amount of hydrogen contained in the hard amorphous carbon is 10 atomic% or more and 30 atomic% or less.

9. The magnetic head according to claim 1, the content of elements contained in the hard amorphous carbon is equal to or less than 10 atomic% 1 atomic% or more carbon .

Claims (6)

[Claims] 1. A magnetic head having a protective film on at least an air floating surface of a magnetic head slider, wherein the protective film contains at least one element that easily bonds to hydrogen and carbon.
A magnetic head comprising hard amorphous carbon containing at least one species and having a thickness of 1 nm or more and 30 nm or less. 2. The method according to claim 2, wherein said element which easily bonds to carbon is V, Z.
2. The magnetic head according to claim 1, wherein r, Hf, and Mo are used. 3. A magnetic head having a protective film on at least the air floating surface of a magnetic head slider, wherein the protective film contains hydrogen and at least one element other than hydrogen.
It is made of hard amorphous carbon having a thickness of 1 nm or more and 30 nm or less, wherein the element easily diffuses into carbon and has a property of easily bonding to a nonmetal element in a slider material. Magnetic head. 4. An element which easily diffuses into the carbon and easily bonds to a nonmetallic element in the slider material is B, Al,
4. The magnetic head according to claim 3, wherein the magnetic head is a lanthanoid excluding Sc, Cr, Mn, Fe, Co, Pb, Y, and Pm. 5. The magnetic head according to claim 1, wherein the amount of hydrogen contained in the hard amorphous carbon is 10 atomic% or more and 30 atomic% or less. 6. The magnetic head according to claim 1, wherein the content of the element contained in the hard amorphous carbon is 1 atomic% or more and 10 atomic% or less with respect to carbon. .