JPH07192254A - Magnetic disk and manufacturing method thereof - Google Patents

Abstract

PURPOSE:To manufacture a magnetic disk dealing with a high recording density, which uses as its protective layer an amorphous carbon film excellent in wear resistance and electrical insulation properties and has improved durability. CONSTITUTION:This magnetic disk is manufactured by laminating the magnetic recording layer 4, protective layer 5 and lubricating layer 6 and the sliding resistance of the disk is improved by using a specific amorphous hydrogenated carbon layer as the carbon based protective layer 5. The amorphous hydrogenated carbon is selected so as to have a Raman spectrum waveform that can be separated into two Gaussian function type waveforms, one of which (A) has its peak in the region of 1520 to 1555cm<-1> and the other of which (B) has its peak in the region of 1320 to 1360cm<-1> and further in which the ratio of the area of the waveform (B) within its half-value width to the area of the waveform (A) within its half-value width is 0.4 to 1.6. Thus, the durability of the magnetic disk is improved and the life of the disk is extended. As a result, the operation of the disk under conditions of low floating height or contact states of the head becomes possible to improve the recording density of the disk.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk and a method for manufacturing the same, and more particularly to mounting on a high-density magnetic disk device used in a wide range from a large computer to a personal computer. The present invention relates to a suitable magnetic disk and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, with the miniaturization and increase in capacity of magnetic storage devices used in computers and the like, there has been a demand for magnetic recording media having high recording density and high reliability. Generally, in order to improve the recording density, it is necessary to make the distance between the magnetic recording film and the magnetic head as small as possible. Therefore, the amorphous carbon film used as a protective film for the magnetic film should be as thin as possible, Moreover, strength is required. Further, a carbon film having a high insulating property is required in order to support a thin film magnetic head (hereinafter abbreviated as MR head) system.

From the above, a lot of research has been conducted on amorphous carbon films in recent years, and the relationship between the film quality and sliding resistance has been investigated. Especially, the evaluation of the film quality based on the Raman spectrum and the hydrogen content has been actively conducted. For example, Japanese Patent Application Laid-Open No. 2-29919 discloses a magnetic recording medium which defines a peak position and a peak ratio of a Raman spectrum, and Japanese Patent Application Laid-Open No. 62-241124 discloses a peak position of a Raman spectrum and a Vickers. In a magnetic recording medium having a specified hardness and specific resistance, and a hydrogen content,
No. 258220 discloses a magnetic disk for a high-hardness slider in which the hydrogen content is specified, and in JP-A-2-71422, the hydrogen content and the peak position of the Raman spectrum are specified, and the sliding resistance of the magnetic recording medium is determined. Is improving.

[0004]

However, in recent years, the demand for improving the recording density is extremely strict, and the flying space of the head is extremely small, and the number of revolutions is increased to improve the data transfer speed. In fact, it is not possible to obtain a film quality exhibiting an optimum sliding resistance property with the above-mentioned conventional technique because of the increase in the film thickness.

Therefore, an object of the present invention is to improve the film structure of the above-mentioned conventional amorphous carbon film and obtain an amorphous carbon film capable of achieving the most excellent sliding resistance as a magnetic disk as a whole. Therefore, it is to provide a magnetic disk that can withstand low flying and rotate at high speed.

[0006]

In order to achieve the above object, the inventors of the present invention rigorously examined the film quality of the amorphous carbon film and conducted various experiments to find the film quality range with the best performance. . Waveform A having a peak at a Raman shift of 1550 to 1600 cm ^-1 and waveform B having a peak at 1350 to 1400 cm ^-1 in a conventional Raman spectrum.
And a peak strength ratio B / A of 0.4 to 0.7 was investigated as a base, and in addition to the above, in the region where these conditions were deviated, and other conditions were also taken into consideration, it was more excellent. It was found that the characteristics could be obtained.

That is, the present invention has been made on the basis of such findings, and the results of the study will be specifically described as follows.

[0008] As an item examined and examined, the Raman spectrum was separated into two peaks, the respective peak positions and half widths, the relationship between the peak area ratio and the wear amount, and further, the film density, the density and the combustion starting temperature. , The content of hydrogen atoms in the film, the hydrogen atom density, the resistivity of the film, and the like.

First, a method for separating the peaks of the Raman spectrum will be described. The Raman spectrum was measured using an argon laser (514.5 nm), the resulting waveform was separated into two by a Gaussian function, and the two obtained waveforms were optimized by the nonlinear least squares method. One example is shown in FIG. 1537c with the waveform separated in this way
The waveform having a peak near m ⁻¹ is A, and the waveform having a peak near 1328 cm ⁻¹ is B.
The full width at half maximum and the peak area ratio (B / A) were determined.

As a result, on the non-magnetic substrate, the magnetic recording film,
In a magnetic disk in which an amorphous carbon film and a lubricating film are laminated, the Raman spectrum waveform of the amorphous carbon film is separated into two Gaussian function type waveforms by Raman scattering spectroscopy measurement obtained at an excitation wavelength of 514.5 nm. Then, the peak position of one waveform A is 1555 to 1520 cm ⁻¹ , preferably 1545 to 1520 cm ⁻¹ , and the peak position of the other waveform B is 1320 to 1360 cm ^−1. By using the amorphous carbon film having the area ratio (B / A) in the value range of 0.4 to 1.6 as the protective layer, a magnetic disk having excellent sliding resistance can be obtained.

The half-value width of the peak position of the waveform A at this time is 80 cm ⁻¹ or more, preferably 80 to 120 cm ⁻¹ , and the half-value width of the peak position of the waveform B is 120 to 160.
It was cm ^-1 . Incidentally, the half-value width of a conventional sputtered carbon is 60～70Cm ^-1 peak position of the waveform A, a 160～170Cm ^-1 at the position of the waveform B.

In order to further improve the performance, the density of the amorphous carbon film is 1.65 to 2.0 g / cm ³ , and the hydrogen content in the film is 20 to 45 atom%. The hydrogen atom density is preferably specified in the range of 2 to 5 × 10 ²² / cm ³ , and a magnetic disk having excellent sliding resistance can be obtained.

The density of the amorphous carbon film, the hydrogen atom density in the film, and the hydrogen atom content were measured by HFS (hydrogen forward scattering analysis) and RBS (Rutherford back scattering analysis). This method can quantify high-concentration hydrogen in the surface layer, which is difficult with other methods. By setting the detector at 30 ° with respect to the helium ion energy (2.275 MeV) and rotating the sample surface so that it is always at 15 ° with respect to the beam, the hydrogen signal scattered in front of the sample can be measured. At the same time, the detector was set at an angle of 160 ° with respect to the incident beam of ions, and the carbon signal was measured.

Considering the combination with a magnetic head, for example, when an MR head is used, the amorphous carbon film used as a protective film of a magnetic disk is required to have high insulation. According to this, the amorphous carbon film having a resistivity of 10 ⁵ Ωcm or more can be obtained, and a magnetic disk excellent in sliding resistance can be obtained without being affected by the kind of the magnetic head to some extent.

Various film forming methods can be adopted for forming the amorphous carbon film of the present invention. For example, when a carbon film is formed on a magnetic recording film by supplying a source gas to a film forming chamber by a plasma CVD method, a hydrocarbon type, a hydrocarbon type + H ₂ , a hydrocarbon type + O ₂ , or CF ₄ , is used as a source gas. A method of forming a film from a reactive gas by setting the substrate temperature and the plasma generation power to predetermined conditions using any of CF ₄ + H ₂ , and more specifically, for example, the substrate temperature is about 200 ° C. It is a method of forming a film by RF plasma CVD using methane gas while maintaining the temperature.

When a carbonaceous target is provided in the film forming chamber and a raw material gas is supplied to form a carbon film on the magnetic recording film by the magnetron sputtering method, CH ₄ , CH ₄ + Ar, A method of forming a film by sputtering using Ar + O ₂ or CH ₄ + H ₂ with the substrate temperature and plasma generation power set to predetermined conditions,
More specifically, for example, the substrate temperature is set to 37
This is a method of holding the film at 3 K or less (preferably about room temperature), using a carbonaceous target, and forming a film by a DC magnetron sputtering method in which an argon gas and a methane gas (CH ₄ + Ar) are introduced.

It is preferable to use a non-magnetic material such as aluminum, glass or ceramics for the non-magnetic substrate, and for the magnetic film, for example, a Co-Cr type alloy or the like is used.

In recent years, a Cr layer and Co have been used as a magnetic recording film.
It is known that noise is reduced by alternately stacking two series alloy layers to form a magnetic film having a two-layer structure. The amorphous carbon of the present invention is formed on the stacked magnetic films. By forming the film, the noise is low and the sliding resistance is excellent, so that the recording density can be improved.

The amount of wear was measured by rotating the substrate on which the amorphous carbon film was deposited and pressing a sapphire slider with a constant load onto the substrate, and the volume of the amorphous carbon film worn by this was measured. Was measured and evaluated as the relative wear amount.

[0020]

In the present invention, the reason why the amorphous carbon protective film having excellent performance can be obtained is as follows. That is, when the waveform of the Raman spectrum is separated into two Gaussian function type waveforms, the peak of A is considered to be due to the peak of graphite (sp ² bond) at 1580 cm ⁻¹ , and therefore the sp ² component is reduced. In order to do so, it is considered that the peak position of A changes and the half-value width widens. So A
When the relationship between the peak position and the amount of wear of the amorphous carbon film is investigated, the result is as shown in FIG. 2, and the peak position is 1580.
The wear amount decreases at cm ^-1 or less, and particularly 1555 to 1520
This trend in cm ^-1 is conspicuous, that of 1540 cm ^-1 to the wear amount of 1580 cm ^-1 was about 4-fold lower. Further, the half-width of A at that time 80cm ^-1 ~120cm ^-1
It was found that it is wider than the conventional 60 to 70 cm ⁻¹ .

Further, the peak of B is considered to be caused by a microcrystal having a disordered double bond, and it is considered that the proportion of crystals having a large cluster size increases when the position of this peak moves to the high wave number side. Therefore, the peak position is preferably 1350 cm ^-1 or less, and considering the wear amount result, the range of 1320 to 1360 cm ^-1 is preferable.

FIGS. 3 and 4 show the peak area ratio (B /
A) shows the relationship between stress and wear amount. When the peak area ratio (B / A) becomes smaller than 0.4, an organic film is formed and the stress (shown in FIG. 3) decreases, which is contrary to the above. Wear amount (shown in FIG. 4) increases. Also, 1.
When it is larger than 6, the proportion of the graphite component in the film increases, the stress decreases, and the amount of wear also increases. Therefore, the peak area ratio is preferably in the range of 0.4 to 1.6 where the amount of wear is small.

The peak area is 1/2 of the height of A and B peaks, that is, the area of the relative intensity in the half-value width, as indicated by the diagonal lines in FIG. The area ratio of two waveforms (B / A) is the value obtained by dividing that of B by the peak area of A.

With high-density recording, the flying height of the magnetic head decreases and the rotational speed of the disk increases. Along with this, it is considered that friction occurs between the head and the disk and the temperature of the disk surface becomes high, and the disk is abraded by combustion, and a protective film having a combustion starting temperature as high as possible is required. Therefore, when the relationship between the density of the carbon film and the combustion starting temperature was examined in detail under the condition satisfying the Raman characteristics, the results shown in FIG. 5 were obtained. Under the conditions that satisfy the above Raman characteristics, the amount of wear and the insulation characteristics serve as guidelines, but it is clear from this characteristic diagram that another condition is required for the combustion resistance, and the density has a deep relationship. Became.

That is, the density in the specific range has an effect of increasing the combustion start temperature, and the combustion start temperature of the conventional amorphous carbon film was at most 523 to 573 K, while the density of the present invention is preferable. At a certain value of 1.65 to 2.0 g / cm ³ , the temperature increased to 623 to 673 K, and in addition to the performance improvement due to the preferable regulation of Raman characteristics, the performance improvement due to the density regulation was further attempted.

FIG. 6 is a result of studying the relationship between the density and the wear amount, and shows the difference between the two manufacturing methods, that is, the sputtering method and the positive bias plasma CVD method.
In any of the manufacturing methods, a low wear amount is shown within the above preferable density range (1.65 to 2.0 g / cm ³ ). Further, the positive bias plasma CVD method exhibits a film quality superior in abrasion resistance to sputtering.

Next, FIG. 7 shows the relationship between the hydrogen content in the film and the amount of wear. Hydrogen content (atomic%) is 20-
A good result is shown in the range of 45%, but it is considered that the graphite component increases in the region of less than 20% and the organic film is formed in the region of more than 45%, and a rapid increase in the amount of wear was observed. . In particular, the hydrogen atom density at that time is preferably 2 to 5 × 10 ²² atoms / cm ³ .

Further, amorphous carbon films having different resistivities were deposited on an actual disk and examined using an MR head.
The amorphous carbon films satisfying the Raman characteristics and the preferable density of the present invention described above all have a specific resistance of 10 ⁵ Ωcm.
Although the good driving state was maintained as described above, in the case of the film which did not satisfy the above conditions of the present invention, the specific resistance was less than 10 ⁵ Ωcm, and the MR head element was destroyed due to charging on the amorphous carbon film.

When the film thickness of the amorphous carbon film as the protective film is thinner than 10 nm, the film cannot be uniformly formed on the substrate by the current technology, and the film is evenly formed. Even so, its strength is quite low. On the other hand, if it is thicker than 50 nm, the distance from the magnetic recording film increases and the electromagnetic conversion characteristics deteriorate, which is not preferable for high density recording. Therefore, the thickness of the amorphous carbon film as the protective film is preferably 10 to 50 nm.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. A comparative example as reference data is shown at the end of this section.

(Embodiment 1) FIG. 8 is a sectional view of a magnetic disk according to an embodiment of the present invention. In the figure, 1 is an aluminum alloy substrate, 2 is a Ni-P alloy film formed on the substrate 1 by electroless plating, 3 is a Cr base film formed by a sputtering method, and 4 is Co-Cr formed by a sputtering method. A magnetic system film, 5 is an amorphous carbon film of the present invention, and 6 is a lubricating film.

First, the disk substrate on which the Ni—P alloy film 2 of FIG. 8 is formed is used as a sample, and the Ni—P alloy film 2 at this time is used.
The surface of is subjected to texture processing with an average roughness Ra of 10 nm, Cr is 100 nm as the base film 3, and then the magnetic film 4 is used.
As a film, a Co-Cr-Ta magnetic alloy film having a thickness of 45 nm was formed, and the amorphous carbon film of the present invention was laminated thereon to a thickness of 20 nm by positive bias plasma CVD.

An example of a method for forming the amorphous carbon film 5 will be described below in detail. First, using a CVD apparatus (not shown), the inside of the vacuum chamber was 1 × 1 by a vacuum pump.
Exhaust to 0 ^-6 Torr. Next, methane gas (CH ₄ )
Is introduced, and the gas flow rate at this time is adjusted to 10 sccm and the gas pressure is adjusted to 50 mTorr.

Then, 1000 W is applied by a high frequency power source of 13.56 MHz to generate plasma discharge in the chamber. The substrate temperature at this time was set to 473K. In this way, the amorphous carbon film 5 having a film thickness of 20 nm was laminated.

The film quality of the amorphous carbon film formed by this positive bias plasma CVD method was as follows.

(1) The A band peak position of the waveform obtained by separating the Raman spectrum into two peaks is 1537c.
m ^-1, B band peak position 1329cm ^-1, A half band width 87cm ^-1, B half band width 144cm ^-1,
The peak area ratio (B / A) was 0.58.

(2) The density of the amorphous carbon film is 1.85 g /
The combustion starting temperature was 673 K in cm ³ . The hydrogen atom content rate is 38%, and the hydrogen atom density is 4.2 × 10 ^22.
It was atoms / cm ³ .

(3) A CSS test (abbreviation of contact start / stop test) was carried out on a magnetic disk formed with this amorphous carbon film as a protective film using a thin film head for practical use. However, the friction coefficient did not change and the disk did not crash. The specific resistance of this carbon film was 10 ¹² Ωcm.

(Example 2) This example is formed by DC magnetron sputtering instead of the positive bias plasma CVD used as the method for forming the amorphous carbon film 5 in Example 1.

By the same method as in Example 1, the Ni of FIG.
The surface of the -P alloy film 2 is textured to have an average roughness Ra of 10 nm, Cr is 100 nm as the underlayer film 3, and Co-Cr-Ta magnetic alloy is 45 nm as the magnetic film 4, and DC magnetron sputtering is performed on the Cr film. The amorphous carbon film of the present invention was laminated to a thickness of 20 nm.

The method of forming the amorphous carbon film 5 will be described in detail below. First, the inside of the vacuum chamber is evacuated to 1 × 10 ⁻⁶ Torr by a vacuum pump using a DC magnetron sputtering film forming apparatus (not shown). Next, methane gas (CH ₄ ) and argon gas (Ar) are introduced, and the gas flow rate at this time is adjusted to 20 sccm of methane gas, 30 sccm of argon gas, and the gas pressure is 4 mTorr. Graphite is used as a target, and 4 kW is applied by a DC power source to generate plasma discharge in the chamber. The substrate temperature at this time was room temperature.

The film quality of the amorphous carbon film 5 formed by this DC magnetron sputtering method is as follows.

(1) The A band peak position of the waveform obtained by separating the Raman spectrum into two peaks is 1544c.
m ^-1, B band peak position 1352cm ^-1, A half band width 89cm ^-1, B half band width 137 cm ^-1,
The peak area ratio (B / A) was 0.62.

(2) The density of the amorphous carbon film is 1.7 g / c.
The combustion starting temperature was 643 K at m ³ . The hydrogen atom content rate is 30%, and the hydrogen atom density is 5 × 10 ²² atoms /
It was cm ³ .

(3) Further, a CSS test of this film was carried out. As with the case of Example 1, the friction coefficient did not change even after 50 k times or more, and a good result was obtained without causing a disk crash. showed that. The specific resistance of this carbon film was 10 ¹⁰ Ωcm.

Example 3 Using the magnetic disk having the structure shown in FIG. 1 of Example 1, the MR head was actually levitated and the discharge breakdown voltage of the amorphous carbon film 5 was measured. With the amorphous carbon film of the present invention, the MR element did not break down and an excellent insulating property was exhibited up to an applied voltage of 10V.

(Embodiment 4) A magnetic disk, a magnetic head (using an MR head) for recording / reproducing information on / from this magnetic disk, a rotating mechanism for rotating the magnetic disk, and recording / reproducing an input / output signal from the magnetic head. The magnetic disk obtained in Example 1 was mounted on a magnetic disk device having a well-known structure including a signal processing unit for performing a performance test of low flying, high-speed rotation, high-density recording, and reproduction. As a result, 50
Even in the CSS test of k times or more, no head crash was observed and good characteristics were exhibited.

COMPARATIVE EXAMPLE 1 This comparative example has a preferable amorphous carbon film density as in Example 1, but the results of hydrogen content and Raman characteristics are not satisfied. The amorphous carbon film was formed using a DC magnetron sputtering device. In addition,
Description up to the magnetic film forming process is omitted because it is the same as in the first embodiment. Hereinafter, the method of forming the carbon film will be described in detail.

First, the vacuum chamber is evacuated to 1 × 10 ^-6 Torr. Next, argon gas is introduced, and the gas flow rate at this time is 30 s of argon gas.
Adjust ccm and gas pressure to 4 mTorr. Graphite is used as a target, and 4 kW is applied by a DC power source to generate plasma discharge in the chamber. The substrate temperature at this time was room temperature.

The film quality of the amorphous carbon film formed by this DC magnetron sputtering method is as follows.

(1) The A band peak position of the waveform obtained by separating the Raman spectrum into two peaks is 1580c.
m ^-1, B band peak position 1387cm ^-1, A half band width 83cm ^-1, B half band width 196cm ^-1,
The peak area ratio was 2.70. (2) The density of the amorphous carbon film is 1.80 g / cm ³ , but the hydrogen atom content is 5% and the hydrogen atom density is 1 × 10 5.
^{It was 22} atoms / cm ³ .

(3) The CSS test results of the amorphous carbon film are
At 20k, the friction coefficient sharply increased and the disk crashed. In addition, the discharge withstand voltage of this amorphous carbon film is 3 V or more and the surface of the amorphous carbon film is electrically charged when the applied voltage is 3 V or more.
The R element is destroyed.

(Comparative Example 2) This Comparative Example has the same amorphous carbon film density and hydrogen content as in Example 1, but does not satisfy the results of Raman characteristics. Only the formation conditions of the amorphous carbon film are different,
The other conditions are the same as those in Comparative Example 1 and therefore omitted, and the method for forming the carbon film will be described in detail below.

First, the vacuum chamber is evacuated to 1 × 10 ^-6 Torr by a vacuum pump. Next, methane gas and argon gas are introduced, and the gas flow rate at this time is adjusted to 25 sccm of methane gas and 25 sccm of argon gas, and the gas pressure is adjusted to 4 mTorr. Graphite is used as a target, and 4 kW is applied by a DC power source to generate plasma discharge in the chamber. The substrate temperature at this time was 200 ° C.

The film quality of the amorphous carbon film formed by this DC magnetron sputtering method is as follows.

(1) The A band peak position of the waveform obtained by separating the Raman spectrum into two peaks is 1565c.
m ^-1, B band peak position 1386cm ^-1, A half band width 71cm ^-1, B half band width 163cm ^-1,
The peak area ratio was 1.66. (2) The density of the amorphous carbon film was 1.68 g / cm ³ , but the hydrogen atom content was 29%.

(3) The CSS test result of the amorphous carbon film is
At 40k or more, the friction coefficient sharply increased and the disk crashed.

COMPARATIVE EXAMPLE 3 This comparative example satisfies the preferable hydrogen content and Raman characteristic results as in Example 1, but does not satisfy the condition of the amorphous carbon film density. Only the formation conditions of the amorphous carbon film are different,
The other conditions are the same as those in Comparative Example 1 and therefore omitted, and the method for forming the carbon film will be described in detail below.

First, the vacuum chamber is evacuated to 1 × 10 ^-6 Torr. Next, methane gas and argon gas are introduced, and the gas flow rate at this time is adjusted to 25 sccm of methane gas and 25 sccm of argon gas, and the gas pressure is adjusted to 4 mTorr. Graphite is used as a target, and 4 kW is applied by a DC power source to generate plasma discharge in the chamber. The substrate temperature at this time was room temperature.

The film quality of the amorphous carbon film formed by this DC magnetron sputtering method is as follows.

(1) The A band peak position of the waveform obtained by separating the Raman spectrum into two peaks is 1538c.
m ⁻¹ , B band peak position is 1338 cm ⁻¹ , A band half width is 85 cm cm ⁻¹ , B band half width is 126 cm.
^-1 , and the peak area ratio was 0.56. (2) The density of the amorphous carbon film was 1.50 g / cm ³ , but the hydrogen atom content was 40%.

(3) The CSS test result of the amorphous carbon film is
At 40 k times or more, the friction coefficient sharply increased, and the disk crashed as in Comparative Example 2.

[0063]

As described above in detail, according to the present invention, the intended purpose can be achieved. That is, since the magnetic disk using the amorphous carbon film of the present invention has significantly improved sliding resistance, it is possible to achieve high density recording and contribute to the practical application of a small and large capacity magnetic storage device. You can

[Brief description of drawings]

FIG. 1 is a peak separation diagram of a Raman spectrum for explaining the principle of the present invention.

FIG. 2 is a characteristic diagram showing the relationship between the peak position of A in the Raman spectrum and the amount of wear.

FIG. 3 is a characteristic diagram showing a relationship between a peak area ratio (B / A) of Raman spectrum and stress.

FIG. 4 is a characteristic diagram showing the relationship between the peak area ratio (B / A) of the Raman spectrum and the wear amount.

FIG. 5 is a characteristic diagram showing the relationship between the density of an amorphous carbon film and the combustion start temperature.

FIG. 6 is a characteristic diagram showing the relationship between the density and the wear amount of the amorphous carbon film.

FIG. 7 is a characteristic diagram showing the relationship between the hydrogen content in the film and the amount of wear.

FIG. 8 is a sectional structural view of a magnetic disk according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Aluminum alloy substrate 2 Ni-P alloy layer 3 Cr underlayer film 4 Co-Cr-Ta magnetic film 5 Amorphous carbon film 6 Lubrication film

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Naruhiko Fujimaki 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Inside the Hitachi, Ltd. Institute of Industrial Science (72) Inventor Hiroshi Inaba 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Incorporated company Hitachi, Ltd., Production Technology Laboratory (72) Inventor Satoru Matsunuma 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Incorporated, Hitachi, Ltd. Production Technology Laboratory (72) Ryo Kitou, Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture No. 292 Co., Ltd. Production Engineering Research Laboratory, Hitachi, Ltd.

Claims (11)

[Claims] 1. A magnetic disk in which a magnetic recording film, an amorphous carbon film, and a lubricating film are laminated on a non-magnetic substrate, and the amorphous carbon is measured by Raman scattering spectroscopy obtained at an excitation wavelength of 514.5 nm. When the waveform of the Raman spectrum of the film is separated into two Gaussian function type waveforms, the peak position of one waveform (A) is 1555 to 1520 cm ⁻¹ and the peak position of the other waveform (B) is 1320 to 1360 cm ⁻¹ . Yes, the area ratio (B /
A) A magnetic disk having an amorphous carbon film of 0.4 to 1.6 as a protective layer. 2. The magnetic material according to claim ¹ , wherein the Gaussian function type waveform (A) has a half width of 80 to 120 cm ⁻¹ and the other waveform (B) has a half width of 120 to 160 cm ^−1. disk. 3. The hydrogen content of the amorphous carbon film is 20-4.
5 atomic% and the density at that time is 1.65 to 2.0 g
The magnetic disk according to claim 1 or 2, wherein the magnetic disk has a density of / cm ³ . 4. The magnetic disk according to claim ³ , wherein the atomic density of hydrogen contained in the amorphous carbon film is 2 to 5 × 10 ²² atoms cm ⁻³ . 5. The thickness of the amorphous carbon film is 10 to 50 nm.
The magnetic disk according to claim 1 or 2, wherein 6. The non-magnetic substrate is composed of an Ni-P-plated aluminum disk substrate having a surface textured thereon, and a Cr layer and a Co-based alloy layer serving as a magnetic recording film are alternately formed on the non-magnetic substrate. The magnetic disk according to any one of claims 1 to 5, wherein the magnetic disk is formed of layers to form a two-layer magnetic film. 7. Plasma CV by supplying a raw material gas to the film forming chamber.
When the carbon film is formed on the magnetic recording film by the D method, a hydrocarbon gas, a hydrocarbon gas + H ₂ , a hydrocarbon gas + O ₂ , or CF ₄ , CF ₄ + H ₂ is used as the source gas, A method of manufacturing a magnetic disk, comprising a step of laminating an amorphous carbon film according to any one of claims 1 to 5 from a reactive gas while setting a substrate temperature and a plasma generation power to predetermined conditions. 8. A carbonaceous target is provided in a film forming chamber, and a raw material gas is supplied to form a carbon film on a magnetic recording film by a magnetron sputtering method.
The amorphous carbon according to claim 1, wherein any one of H ₄ , CH ₄ + Ar, Ar + O ₂ , and CH ₄ + H ₂ is used to set the substrate temperature and the plasma generation power to predetermined conditions and the sputtering is performed. A method of manufacturing a magnetic disk, comprising a step of laminating films. 9. A step of plating Ni-P on an aluminum disk substrate, a step of texturing the surface thereof, a step of forming a Cr film as a base film thereon, and a magnetic film thereon. In the method for manufacturing a magnetic disk, the method further comprises the steps of depositing a Co-based alloy by sputtering, forming an amorphous carbon film on the magnetic film, and further forming a lubricating film. A method for manufacturing a magnetic disk, comprising the step of forming a crystalline carbon film, the step of laminating an amorphous carbon film according to claim 8 or 9. 10. A magnetic disk, a magnetic head for recording / reproducing information on / from the magnetic disk, a rotation mechanism section for rotating the magnetic disk, and a signal processing section for recording / reproducing an input / output signal from the magnetic head. 7. A magnetic disk device comprising the magnetic disk according to claim 1.
A magnetic disk device comprising the magnetic disk according to any one of the above. 11. A magnetic disk drive according to claim 10, wherein the magnetic head is an MR head.