JP2001110031A - Carbon film, magnetic disk to which carbon film is applied, method for manufacturing the same, and magnetic head - Google Patents

Abstract

(57) Abstract: preventing destruction due to separation mode of the amorphous carbon film to a certain but mainly SP ³ bond of the high stress in the high hardness, to provide a carbon film having a sufficient strength even in extremely thin.
Also, the present invention provides a magnetic disk and a magnetic head which are suitable for improving a high recording density and improving sliding resistance by using the carbon film as a protective layer. A mainly consists of carbon atoms of the amorphous structure including an amorphous structure or a fine crystal, between the carbon atom bonded to the surface of a film composed mainly of SP ³ bond, the internal stress is dispersed a low stress relaxation region from the surrounding Formed. The coating is formed as a protective layer on the ferromagnetic layer of the magnetic disk. The film is formed as a protective layer on the slider portion and the element portion of the magnetic head.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a film mainly composed of carbon, and more particularly, to a magnetic disk disk and a magnetic head mounted on a magnetic disk device to which this film is applied as a protective layer.

[0002]

2. Description of the Related Art With the progress of miniaturization of electronic devices, improvement of the performance of various protective films (protective layers) has become an important development task in order to improve the reliability. In the development of a magnetic disk device which is important as an external memory of a computer, the development of an ultra-thin protective layer has become an important issue in improving the performance of a magnetic disk and a magnetic head.

That is, the storage capacity required for a magnetic disk drive has been increasing year by year, and a dramatic improvement in recording density and an improvement in transfer speed are constantly required. In order to meet this requirement, the distance between the magnetic head and the recording medium has been reduced to the utmost limit, the recording track has been narrowed, and a low-noise high-output medium, a high-sensitivity reproducing element, and advanced signal processing technology have been developed. However, the technologies used in the past become obsolete immediately and new technologies are needed. In particular, a protective layer for protecting a recording medium of a magnetic disk needs to be further thinned in order to reduce a recording space. Conventionally, an amorphous carbon film having a hardness of 5 to 20 GPa or a diamond-like carbon film is used.
Even though the diamond-like, SP ² bond is contained considerable, this is the thickness of 2 to 3 nm, it is impossible to achieve the very satisfactory protective effect. Further in order to increase the strength of the need to tightly binding, better to increase the SP ³ bond ratio. In general, a substance having a stable SP ³ bond is diamond, which is crystalline and very hard but also has fragile properties. Therefore, even if diamond alone has sufficient strength, a very thin film having a thickness of 2 to 3 nm cannot avoid deformation from the base, and even a slight deformation due to brittleness can lead to destruction. On the other hand, carbon mainly composed of amorphous has a property suitable for a protective film that functions as an elastic body against deformation and returns to its original state when the load is removed. Recently, SP ³ has been used for filtered cathodic arc method and ion beam deposition method.
Amorphous carbon mainly composed of bonds can be formed, and its ratio is more than 50% and 80 to 90%.
Also reach. These have a hardness close to that of diamond, and have a large elastic recovery force because of their low Young's modulus.
This can be said to be the most preferable property for an extremely thin film. However,
These have a drawback that they have a large compressive stress because their bonding state involves distortion, and therefore they are easily separated from the magnetic layer to be protected. It is common practice to provide an adhesion layer in order to prevent peeling.
No. 131 discloses an example in which Si is used as an adhesion layer. Although this method is certainly effective, according to the disclosed example, the film does not function as an adhesion layer unless the film thickness is at least 5 nm or more. Therefore, it is necessary to reduce the total film thickness to preferably 3 nm or less. Cannot be used for the protective layer targeted by the present invention.

[0004]

[0008] The present invention is to solve the above problems, prevents the destruction by peeling mode of amorphous carbon film to a certain but mainly SP ³ bond of the high stress at high hardness, as a result, pole An object of the present invention is to realize a protective film having a sufficient strength even if it is thin so as to endure practical use. Another object of the present invention is to provide a new technique for applying the protective film to a magnetic disk and a magnetic head for a high recording density and high reliability magnetic disk device.

[0005]

According to the present invention, it has been found that partial stress relaxation and partial structural change of the protective film are effective for solving the above-mentioned problems. That is, the first
As shown in the figure, a minute region of the protective layer (protective film) is made into a stress relaxation region or a structure change region by a specific process, and is dispersed. The stress relaxation region or the structure change region is formed by irradiating an electron beam, a laser beam, a hydrogen ion beam or the like converged on the surface of the protective film in a certain pattern. It has been found that dispersing and distributing such stress relaxation portions or structural change portions absorbs high stress in the vicinity, and as a result, has an effect of preventing film peeling.

Since the hardness of the portion where the stress is reduced slightly decreases with the decrease in the stress, the strength of the whole film is weakened when the amount is too large, and no effect is obtained when the amount is too small. % Or more and 10% or less. In order to form such a dispersed state, for example, a method of continuously irradiating a beam while rotating the disk, changing the radial position and processing the beam spirally, and similarly, irradiating the pulse with the beam while rotating the disk , A method of sweeping a pulse beam, a method of irradiating a holographic pattern, and the like. Further, the effect of stress relaxation or structural change can be adjusted by adjusting the irradiation amount per unit area or the irradiation time.

A film having a high internal stress as used in the present invention is:
Generally, the film is formed in a vacuum. FIG. 2 shows an example of an apparatus used in a filtered cathodic arc method which is a typical forming method. According to this method, an arc discharge is generated on a graphite cathode, only C ⁺ among the generated ion species is selected by a selection magnetic field, and then the entire surface of the substrate is irradiated with a beam by a sweep magnetic field, thereby forming a film. In such a film, since the stress is high and the adhesion to the normal substrate interface is small, oxygen, moisture, etc. act on a defect or an interface in the film at the moment when the film is taken out into the atmosphere, and react. Peeling often starts. In Journal of Vacuum Science and Technology, Vol. A13, No. 2, pp. 406 to 411, a technique for accelerating a beam to form a mixing layer with a base material and adhere thereto is introduced. However, the ultra-thin protective layer on the magnetic layer intended in the present invention cannot be employed because it may damage the magnetic layer and increase the film thickness.

In addition, in a method of forming diamond-like carbon generally such as an ion beam deposition method or a plasma decomposition method, a hydrocarbon material having a low hydrogen ratio such as C ₂ H ₂ is used, or a plasma density is reduced. If the conditions such as enhancing the decomposition and promoting the decomposition are selected, the hydrogen ratio is small and SP
^In some cases, amorphous carbon with a high ratio of ³ can be formed.

[0009] In principle, to the exclusion of graphite clustering component, a single atom, by performing single ionic deposition, the SP ³ bond between carbon atoms necessary for the present invention to obtain an amorphous carbon is the main component Although not limited to the above method, most of the steps are performed in a vacuum or at a low gas pressure. Therefore, in consideration of the effects of oxygen and moisture as described above, it is needless to say that performing the treatment of the present invention immediately after film formation in a vacuum is more effective. For this purpose, for example, in a continuous vacuum processing apparatus, the substrate can be transferred from the film forming chamber to the processing chamber and processed without time delay.

FIG. 3 shows an example of a method for forming a stress relaxation region according to the present invention. That is, while rotating the disk substrate, the laser light source is moved in the radial direction of the disk in a) and the electron beam is radially shaken by the magnetic field generating coil used in the display in b) to perform the processing over the entire surface. I have.

FIG. 4 shows an example of a method of dispersing the stress relaxation region. In FIG. 4A, a dot-shaped dispersion region is formed by a pulse beam, and in FIG. 4B, a spiral line is formed by a continuous beam. Creating an area.

The present invention relates to the above-mentioned JP-A-62-88131.
Unlike the publication, the separation is not prevented by providing an intermediate layer at the interface, but by properly relaxing the stress of the film itself. Therefore, there is a feature that the distance between the head and the medium does not increase due to the thickness of the intermediate layer, and that the deterioration of the sliding resistance due to the weakness of the material of the intermediate layer can be prevented. Incidentally, assuming that a method similar to the present invention is used,
Japanese Patent Application Laid-Open No. 64-82321 discloses an example in which a diamond-like carbon film is irradiated with a laser pulse to disperse and form a graphite film. However, this example is different from the present invention in both the object and the film structure. That is, in this example, the diamond-like carbon film is subjected to a strong treatment until its crystallinity is changed to partially generate graphite, and the friction coefficient is reduced by utilizing its lubricity. In the ultra-thin region targeted by the present invention, if a strong treatment is performed until graphite is generated, the abrasion resistance becomes extremely insufficient. Therefore, it must be modified in the state of amorphous carbon. For this purpose, the reforming is realized by changing a part of the SP ³ bond into an SP ² bond or by replacing the structure with hydrogen or the like.

The most common method for measuring SP ³ bonds in a carbon film is the NMR method, but it cannot be performed without a sufficient amount of sample. The structural analysis of carbon thin film such as the present invention is a Raman spectrum is most frequently used, the spectrum obtained with normal wavelength of the light source of 514.5nm used are mostly those from SP ² components. To determine the SP ³ component, it is possible to use a Raman spectrum method using a near-ultraviolet light source, the peak intensity in the vicinity 1,200Cm ^-1, it is possible to estimate the SP ³ ratio of approximately. Also, from the Raman spectrum of the 514.5 nm light source, S
The effect of SP ³ around P ² can be estimated,
As the wave number of the main peak is low in 1,500~1,600cm ^-1, also as auxiliary peak in 1,300～1,450Cm ^-1 is small, SP ³ bond there are many around the SP ² bond If the sub-peak is hardly visible, S
P ³ can be estimated to be the main component. As for the hardness measurement, if it exceeds 40 GPa, can be estimated to be the SP ³ bond principal.

The substrate that can be used in the present invention is a substrate obtained by processing glass, NiP-plated aluminum, or other non-magnetic substrate into a desired disk shape and polishing the surface. The surface is further provided with mechanical strength and impact resistance. Another coating can be provided for the purpose of improvement.

The magnetic recording layer used in the present invention is a multi-layer film including a layer made of a ferromagnetic material thin film (referred to as a magnetic layer). The magnetic recording layer is made of a non-magnetic material to control the crystal growth of the ferromagnetic material thin film. A layer (called an underlayer) can be provided.
Both the magnetic layer and the underlayer may be multilayer films composed of a plurality of layers. On this, a lubricating layer can be formed after providing a protective layer which is a feature of the present invention.

As the lubricating layer used in the present invention, a layer mainly having perfluoropolyether as a main chain and having a terminal substituted with a group having a certain affinity with the protective layer is often used.

The thickness of the protective layer in the present invention is 5 nm or less, preferably 3 nm or less.
A large amount of energy is required to perform the process that only overcomes the stress, and the temperature of the layer below the protective layer and the substrate increases, resulting in adverse effects such as deformation.

In the above description, the structure of the present invention has been mainly described as being applied to a protective layer of a magnetic disk as an example. However, the structure of the present invention is similarly applied to a slider surface of a magnetic head and / or Alternatively, it can be used as a protective layer on the element surface. Further, other sliding members can be similarly applied as an extremely thin film.

FIG. 6 is a sectional view of a magnetic head provided with a protective layer according to the present invention. The protective layer is provided directly on the slider portion and the element portion of the magnetic head without an intervening adhesive layer.

In the present invention, when a small portion of the protective layer is rapidly heated by a focused energy beam such as an electron beam, a laser beam, or a hydrogen ion beam, a distorted bond between carbon atoms is partially dissociated and recombined to form an internal portion. Relieve stress.
By appropriately arranging such stress relaxation portions, high stress in the vicinity can be absorbed, and as a result, there is an effect of preventing stress peeling of the film.

It was concluded from the following experiments that the internal stress in the above-mentioned treated portion was reduced. That is, a 20-nm Berkovich-type (triangular pyramid) indenter for measuring microhardness is pressed into a 5 nm-thick protective film on a 50 nm-thick Cr film, and the subsequent indentation is examined by AFM. From the shape, the stress at that point can be compared. It was found that in the part subjected to the stress relaxation treatment, the lift was smaller and the internal stress was reduced as compared with the part not treated.

In order to examine the change in the film structure due to the stress relaxation treatment, the spectra of the processed portion and the unprocessed portion were measured with a microscopic Raman spectrometer. higher than 1,540Cm ^-1 in the processing unit whereas 500cm was around ^-1, it was found that some of the SP ³ bond is converted to SP ² bond.

As described above, the distorted SP ³ bond, which is a cause of high compressive stress, is partially replaced with SP ² to prevent the separation by alleviating the distortion. It is no different from a diamond-like carbon having a low hardness, and the strength of the ultra-thin film intended by the present invention cannot be secured. However, if such stress relaxation regions are formed at regular intervals, the stress strain between the regions is temporarily relaxed at the place, so that the stress distortion as a film is greatly relaxed.

[0024]

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

Example 1 A glass substrate processed into a disk shape having a diameter of 65 mm and having a smooth surface was prepared, washed with a detergent and pure water in advance to clean the surface, and then dried. Next, this substrate was set in a film forming apparatus for a disk, and the following processing was performed while sequentially sending the substrates to another processing chamber in a vacuum.

1) Formation of NiP sputtered layer 2) Substrate heating 3) Formation of magnetic layer under Cr alloy 4) Formation of magnetic layer of Co alloy 5) Formation of carbon protective layer 6) Stress relaxation treatment of carbon protective layer The conditions for each process are as follows.

NiP layer; film thickness 100 nm Substrate heating; surface temperature immediately after heating 230 ° C. Lower magnetic layer composition and film thickness: Cr 0.8 Mo 0.2, 20 nm Magnetic layer composition and film thickness: Co 0.7 Cr 0.2 Pt 0.08
Ta 0.02, 16 nm Protective layer thickness: 3 nm The protective layer is formed by using the above-described filtered cathodic arc method at an acceleration voltage of 50 V and a film formation rate of 0.5 nm.
/ S. Subsequently, an electron beam pulse narrowed to a diameter of about 5 μm was swept by a deflection coil to form an electron beam irradiation processing area in a dot shape with an interval of about 50 μm over the entire surface of the substrate.

Next, the substrate is taken out of the film forming apparatus, and a Fomblin lubricant whose terminal is replaced by an OH group is uniformly applied to a thickness of 10 A by a dipping method. Rotate at 000 rpm, # 1
A 000 abrasive tape was pressed softly to remove surface protrusions.

The completed magnetic disk was assembled in a direct-load type magnetic disk drive, a recording / reproducing head was set, and a durability test was repeated in which start-up, direct load, seek, and unload cycles were repeated. . After 500k cycles, the drive was disassembled, and the disc was inspected for damage. Visual inspection, optical microscope and light scattering type surface defect inspection device showed no damage due to the head hit, and worked well. I knew I was doing it. When the surface of this disk was evaluated with a microscopic laser Raman spectrometer, the portion not irradiated with the electron beam had a spectrum as shown in FIG. 5 a), whereas the portion which was not irradiated was as shown in FIG. 5 b). And the main peak wave number is shifted to a higher wave number side by about 40 cm ^−1, indicating that the SP2 coupling component is increased. The microhardness of each part was measured with a nano indenter.
a, It was found that the processing unit changed to 15 GPa.
It is estimated that this value is not the true hardness of the carbon film but is lower due to the influence of the magnetic layer.

Comparative Example 1 In Example 1, when the electron beam treatment was not performed, a crash occurred during the durability test. When the substrate was disassembled and the substrate surface was examined, scratches could be visually confirmed, and fine peeling of the protective film was observed at and around the scratch origin.

Comparative Example 2 In Example 1, the protective layer was a diamond-like carbon film formed by plasma CVD of ethylene, and other film configurations and the thickness of the protective layer were the same as in Example 1.
When the same durability test as in Example 1 was attempted in the same manner as in Example 1, in the process for removing protrusions, five out of ten sheets were scratched, and those without scratches were also evaluated in the durability test.
Crashed within 0k times. SP ³ ratio 40% of the diamond-like carbon film, film hardness at an indentation depth of 5nm on the disk was 16 GPa.

Example 2 The same experiment as in Example 1 was carried out, except that the electron beam diameter and the interval were changed little by little.

Electron beam diameter (μm) Interval (μm) Treated area ratio Presence / absence of peeling after endurance test 1 5 3.1% None 3 15 3.1% None 10 50 3.1% None 20 100 3.1% No, but processing part wear 5 10 19.6% No, wear 5 14 10.0% No 5 20 4.9% No 5 40 1.2% No 5 60 0.5% Micro peeling 5 100 0 0.2% Yes 5 500 0.007% Separation by protrusion removal processing From this result, it is understood that the effect is large when the area ratio of the processed part is 1% or more and 10% or less.

Example 3 In Example 1, only the protective layer forming step was changed as follows. That is, a 1: 1 mixed gas of helium and acetylene gas is introduced into a vacuum vessel equipped with an ion gun to be ionized. Positive ions are further extracted while applying an acceleration voltage of 100 V, and the disk substrate is irradiated with hydrogen by irradiating it. An amorphous carbon film containing 5% was formed. The film hardness of this film at a pressing depth of 5 nm on the disk was 26 GPa. Further, a film was formed on a silicon wafer under the same conditions, and the internal stress was measured from the amount of deformation to be 6 GPa. When this disk was subjected to a durability test in the same manner as in Example 1, no damage or peeling was observed, and the disk was good.

<< Embodiment 4 >> In Embodiment 1, the electron beam pulse is changed to a continuous beam, and a width of 3
The processing was performed so as to be 100 μm and an interval of 100 μm. The beam current per unit area was adjusted so that the Raman spectrum peak position at the center of the irradiated portion became 1,530 cm ^-1 or more. Other than that, a magnetic disk was prepared and a durability test was performed in the same manner as in Example 1, and no damage or peeling was observed.

Example 5 The same experiment as in Example 4 was carried out except that the width and interval of the electron beam were changed little by little.
It looks like this:

Electron beam width (μm) Interval (μm) Area ratio of treated part Presence / absence of peeling after endurance test 150 2% No 3 150 2% No 10 500 2% No 20 1000 2% No, but processing part wear 3 300 1% No 3 1000 0.3% Peeling off 3506 6% No 3 20 15% Slight wear From these results, it is effective when the width of the processing section is 1 μm to 10 μm and the area ratio is also 1% or more and 10% or less. Is large.

Embodiment 6 In Embodiment 1, after the film is formed up to the protective layer, the substrate is once taken out, the substrate is chucked on a spindle and rotated at 100 rpm, and a laser beam pulse of 5 μm spot is irradiated, and a radial interval is applied. Laser irradiation was performed in the form of a dot having a diameter of 20 μm and an interval of 50 μm in the circumferential direction. The pulse energy and the pulse width were adjusted so that the Raman spectrum peak position at the center of the irradiation part became 1,530 cm ^-1 or more. Other than that, a magnetic disk was prepared and a durability test was performed in the same manner as in Example 1, and no damage or peeling was observed.

Example 7 After forming a GMR element, a recording element and a protective Al ₂ O ₃ layer on an Al ₂ O ₃ —TiC wafer, the magnetic head was formed by cutting, processing, and polishing into a slider shape. Next, a carbon protective layer having a thickness of 3 nm was formed on the sliding surface side of the head by the same filtered cathodic arc method as in the formation of the protective layer in Example 1. Then diameter 3
An electron beam of μm was irradiated in a spot form in a matrix at an interval of 15 μm. However, the element part was avoided. The magnetic head thus manufactured was taken out and used as a head for the durability evaluation test described in Example 1. Observation of the head slider surface after the 500k cycle test showed no peeling and no damage.

Example 8 In Example 6, only the formation of the carbon protective layer was performed without performing the electron beam processing.
One day after being taken out into the air, micro-peeling was already observed, and in the durability evaluation, the whole surface was already peeled after several tens of tests.

[0041]

According to the present invention, even if the thickness is substantially 3 nm or less, there is no problem of peeling off from the substrate to be formed, and the carbon film has sufficient strength and sliding resistance. Can be obtained. Further, by applying this carbon film to a protective layer of a magnetic disk or a magnetic head, it is possible to obtain a magnetic disk or a magnetic head that is suitable for high recording density and has excellent reliability.

[Brief description of the drawings]

FIG. 1 is a sectional view showing the structure of a magnetic disk according to the present invention.

FIG. 2 is a schematic view showing one example of a method for forming a protective film according to the present invention.

FIG. 3 is a schematic view illustrating a method for forming a stress relaxation region according to the present invention.

FIG. 4 is a schematic view showing a dispersion state of a stress relaxation region in the present invention.

FIG. 5 is a Raman spectrum of an untreated portion and a stress relaxation treated portion in the present invention.

FIG. 6 is a sectional view of a magnetic head provided with a protective layer according to the present invention.

[Explanation of symbols]

 1: Substrate 2: Underlayer 3: Magnetic layer 4: Protective layer 5: A layer 6: B layer 7: Lubricating layer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) G11B 5/84 G11B 5/84 B 5D042 21/21 101 21/21 101K 5D112 // C03C 17/22 C03C 17 / 22 Z 17/36 17/36 (72) Inventor Shigehiko Fujimaki 2880 Kozu, Kodahara City, Kanagawa Prefecture Inside the Hitachi, Ltd.Storage Systems Division (72) Inventor Toshinori Ohno 2880 Kozu, Kozu, Odawara City, Kanagawa Hitachi F-term in the Storage Systems Division of the Works (Reference) FA02 FA09 5D033 AA02 BA62 CA03 DA03 5D042 NA01 PA10 SA03 5D112 AA07 AA24 BC05 GA02 GA19

Claims (21)

[Claims] 1. A film mainly composed of carbon having an amorphous structure or an amorphous structure containing microcrystals,
A carbon film, wherein the bonds between carbon atoms are mainly composed of SP ³ bonds, and stress relaxation regions having lower internal stress than the surroundings are dispersed in the surface of the film. 2. A magnetic disk comprising a ferromagnetic layer provided directly on a nonmagnetic substrate via a nonmagnetic underlayer or a protective layer on the surface thereof, wherein the protective layer has an amorphous structure or an amorphous structure containing microcrystals. A protective film mainly composed of carbon, wherein the bond between carbon atoms is SP
A magnetic disk mainly comprising ^three bonds, wherein a stress relaxation region having an internal stress lower than its surroundings is dispersed in a plane of the protective layer. 3. A magnetic disk according to claim 2, wherein a lubricating layer is provided on said protective layer. 4. The method according to claim 2, wherein the size of the stress relaxation region of the protective layer is a line shape having a width of 1 μm to 10 μm or a dot shape having a diameter of 1 μm to 10 μm. A magnetic disk, wherein the total is 10% or less of the area of the protective layer. 5. The magnetic disk according to claim 2, wherein an internal stress in the vicinity of the center of the stress relaxation region of the protective layer is 3 GPa or less. 6. A magnetic disk comprising a ferromagnetic layer provided directly on a non-magnetic substrate via a non-magnetic underlayer and a protective layer provided on the surface thereof, wherein the protective layer has an amorphous structure or an amorphous structure containing microcrystals. A protective film mainly composed of carbon, wherein said protective layer is 514.5n.
of the Raman spectrum measured with a laser light source of
A magnetic disk, wherein a region where the center wave number of a main peak located between 000 cm ^{-1 and} 2,000 cm ^-1 is shifted to a higher wave number side as compared with other regions is dispersed. 7. A magnetic disk comprising a ferromagnetic layer provided on a nonmagnetic substrate via a nonmagnetic underlayer or directly, and a protective layer provided on the surface thereof, wherein the protective layer has an amorphous structure or an amorphous structure containing microcrystals. A protective film mainly composed of carbon, wherein the protective layer comprises carbon of SP
A magnetic disk characterized in that regions in which the ratio of ^two bonds to SP ³ bonds is larger than other regions are dispersed. 8. A magnetic disk comprising a ferromagnetic layer provided directly on a non-magnetic substrate via a non-magnetic underlayer, and a protective layer provided on the surface thereof, wherein the protective layer has an amorphous structure or an amorphous structure containing microcrystals. A magnetic disk, wherein a protective film mainly composed of carbon has a structure in which regions in which the hydrogen concentration in the protective layer is higher than other regions are dispersed. 9. A method of manufacturing a magnetic disk, comprising: providing a ferromagnetic layer on a nonmagnetic substrate via a nonmagnetic underlayer or directly; and providing a protective layer on the surface of the ferromagnetic layer.
A method for manufacturing a magnetic disk, comprising, after forming the protective layer, performing a stress relaxation treatment on a dispersed portion of the surface of the protective layer. 10. The method for manufacturing a magnetic disk according to claim 9, further comprising the step of providing a lubricating layer on said protective layer. 11. The method according to claim 9, wherein the protective layer is formed by a filtered cathodic arc method, and the stress relaxation region is formed by irradiating a converged beam of light. A method for manufacturing a magnetic disk. 12. A magnetic disk according to claim 9, wherein said protective layer is formed by a filtered cathodic arc method, and said stress relaxation region is formed by irradiating a focused beam. Manufacturing method 13. The method according to claim 9, wherein the protective layer is formed by a filtered cathodic arc method, and the stress relaxation region is formed by irradiating a focused ion beam. Manufacturing method of magnetic disk 14. A method for manufacturing a magnetic disk according to claim 9, wherein said protective layer is formed by an ion beam method using hydrocarbon as a raw material. 15. A step of providing a ferromagnetic layer on a non-magnetic substrate, and mainly comprising carbon having an amorphous structure or an amorphous structure containing microcrystals, wherein the bonds between carbon atoms have 50% or more of SP ³ bonds. A method for manufacturing a magnetic disk, comprising: providing a protective layer; stress relaxing a dispersed portion of the protective layer surface; and providing a lubricating layer on the protective layer. 16. The stress relaxation step is performed by irradiating a laser beam, an electron beam, or an ion beam converged while rotating or rotating the disk in a continuous or pulsed manner, and sweeping the irradiated portion in the radial direction of the disk. 16. The method of manufacturing a magnetic disk according to claim 9, wherein: 17. The stress relaxation step according to claim 9, wherein after forming the protective layer, the stress relaxation process is performed continuously without taking out from the vacuum equipment to the atmosphere. 13. The method for producing a magnetic disk according to any one of the preceding items. 18. A magnetic head in which a protective layer made of carbon is directly formed on a slider surface of a magnetic head used in a magnetic disk drive, wherein the protective layer mainly consists of carbon having an amorphous structure or an amorphous structure containing microcrystals. A magnetic head characterized in that a bond between atoms is a protective film having 50% or more of SP ³ bond, and a stress relaxation region having an internal stress lower than that of the protective film is dispersed in a plane of the protective layer. 19. A magnetic head in which a protective layer made of carbon is formed directly on a slider surface of a magnetic head used in a magnetic disk drive, wherein the protective layer mainly comprises carbon having an amorphous structure or an amorphous structure containing microcrystals. Raman spectra of 1,000cm ^-1 ~2,000cm measured layer by a laser light source of 514.5nm
A magnetic head characterized in that a region where the center wave number of a main peak located between ^{-1 and} the other region is shifted to a higher wave number side is dispersed. 20. A magnetic head in which a protective layer made of carbon is formed directly on a slider surface of a magnetic head used in a magnetic disk drive, wherein the protective layer is mainly made of carbon having an amorphous structure or an amorphous structure containing microcrystals. A magnetic head characterized in that regions in which the ratio of SP ² bonds to SP ³ bonds of carbon in a layer is larger than other regions are dispersed. 21. A magnetic head in which a protective layer made of carbon is formed directly on a slider surface of a magnetic head used in a magnetic disk drive, wherein the protective layer mainly consists of carbon having an amorphous structure or an amorphous structure containing microcrystals. A magnetic head, wherein the bonds between atoms are a protective film having 50% or more of SP ³ bonds, and regions in which the hydrogen concentration in the protective layer is higher than other regions are dispersed.