JP2009080897A - Manufacturing method of perpendicular magnetic recording disk and perpendicular magnetic recording disk - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance an SNR and playback signal quality by increasing an exchange coupled magnetic field of a soft magnetic layer. <P>SOLUTION: In a manufacturing method of a perpendicular magnetic recording disk 100, at least a first soft magnetic layer 114a, a non-magnetic spacer layer 114b, a second soft magnetic layer 114c which forms an anti-ferromagnetic coupling (AFC) structure together with the first soft magnetic layer and a magnetic recording layer 122 are sequentially film-deposited on a disk substrate 110 using a sputtering system 200 and the spacer layer 114b is film-deposited in an atmosphere containing a rare gas having an atomic radius larger than that of argon. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a perpendicular magnetic recording disk mounted on an HDD (hard disk drive) or the like, and a perpendicular magnetic recording disk.

  Various information recording techniques have been developed with the recent increase in information processing capacity. In particular, the surface recording density of HDDs using magnetic recording technology continues to increase at an annual rate of about 100%. Recently, an information recording capacity exceeding 160 GB has been required for a 2.5-inch diameter perpendicular magnetic recording disk used for HDDs and the like, and in order to meet such a demand, one square is required. It is necessary to realize an information recording density exceeding 250 Gbits per inch.

  In recent years, a perpendicular magnetic recording type magnetic disk (perpendicular magnetic recording disk) has been proposed in order to achieve a high recording density in a magnetic disk used for an HDD or the like. The perpendicular magnetic recording system is adjusted so that the easy axis of magnetization is oriented in the direction perpendicular to the disk substrate surface. Compared to the conventional in-plane recording system, the perpendicular magnetic recording system can suppress the thermal fluctuation phenomenon by improving the coercive force Hc due to the refinement of the magnetic grains, and thus is suitable for increasing the recording density.

  In the above-described perpendicular magnetic recording system, a single pole type perpendicular head is used to generate a magnetic field perpendicular to the magnetic recording layer. However, simply using a single magnetic pole type vertical head makes it impossible to apply a sufficiently strong magnetic field to the magnetic recording layer because the magnetic flux exiting the single magnetic pole end immediately returns to the return magnetic pole on the opposite side. Therefore, a strong magnetic field in the perpendicular direction is applied to the magnetic recording layer by providing a soft magnetic layer under the magnetic recording layer of the perpendicular magnetic recording disk and forming a magnetic path in the soft magnetic layer. That is, in the soft magnetic layer, the magnetization direction is aligned by the magnetic field when writing, and a magnetic path is dynamically formed. A method of forming such a soft magnetic layer, particularly a single-layer soft magnetic layer, in a short time is disclosed (for example, Patent Document 1).

  Thus, the soft magnetic layer is a layer used when writing information, and the magnetization direction is aligned along the magnetic field at the time of writing. However, when reading, a magnetic field that aligns the magnetization direction is not applied to the soft magnetic layer, so the magnetization direction is basically irregular. Since this irregular magnetization direction is three-dimensional, if a perpendicular component is included in the magnetization direction, it may be picked up as noise together with the signal of the magnetic recording layer when reading with the magnetic head.

  Therefore, for the soft magnetic layer, an AFC (Antiferro-magnetic exchange coupling) structure was proposed and implemented in which the soft magnetic layer was divided into two layers and a nonmagnetic spacer layer was interposed between them. ing. In the AFC structure, the magnetization direction is reversed between the lower layer and the upper layer, and they are coupled and fixed by attracting each other (exchange coupling). Therefore, the magnetization directions of the soft magnetic layers when no magnetic field is applied are antiparallel to each other (parallel and opposite to each other), and parallel to the main surface of the substrate. As a result, the noise generated from the soft magnetic layer can be reduced because the perpendicular component of magnetization is extremely reduced.

  The strength of exchange coupling in the AFC structure is represented by an exchange coupling magnetic field (Hex). As the exchange coupling magnetic field is stronger, the magnetization direction of the soft magnetic layer is less affected by an external magnetic field, and magnetic path formation due to a leakage magnetic field can be prevented, so that SNR (Signal-Noise Ratio) can be improved. .

  In addition, magnetic domains are formed in a single soft magnetic layer not having an AFC structure, and no magnetic domains are formed in a soft magnetic layer having an AFC structure. Here, the magnetic domain (domain) is a region in which the magnetization direction is the same direction, and when the magnetic domain is formed, a domain wall (domain wall) is formed at the boundary of the magnetic domain. Since the magnetization direction of the domain wall is reversed, when the magnetic head passes through the domain wall, the signal level is suddenly increased and detected as spike noise.

In the soft magnetic layer having the AFC structure, the upper and lower soft magnetic layers are each made into a single magnetic domain, and the occurrence of the domain wall is prevented, so that spike noise can be reduced. That is, in the perpendicular magnetic recording disk having the AFC structure, spike noise is reduced in addition to the perpendicular component (noise) in the magnetization direction.
JP 2004-234746 A

  As described above, in the perpendicular magnetic recording disk having the AFC structure, the magnetization stability of the soft magnetic layer increases as the exchange coupling magnetic field increases, and noise caused by the soft magnetic layer can be suppressed. Therefore, an increase in the exchange coupling magnetic field of the soft magnetic layer is indispensable for increasing the recording density and the quality of the reproduced signal. However, the magnitude of the exchange coupling magnetic field in the AFC structure of the soft magnetic layer which is currently mainstream. Is not necessarily enough.

  The present invention has been made in view of the fact that such an exchange coupling magnetic field does not reach a sufficient strength, and an object of the present invention is to increase the SNR by increasing the total exchange coupling magnetic field of the soft magnetic layer. And a method of manufacturing a perpendicular magnetic recording disk and a perpendicular magnetic recording disk capable of improving the reproduction signal quality.

  The inventor has intensively studied the factors that hinder the increase in the exchange coupling magnetic field. As a result, the exchange coupling magnetic field peaks in the spacer layer interposed between the two soft magnetic layers in DC magnetron sputtering (hereinafter simply referred to as sputtering). The film thickness is not uniform in the current sputtering, even if the film thickness is thicker or thinner than the desired thickness, resulting in deterioration of the exchange coupling magnetic field, The present inventors have conceived that the total exchange coupling magnetic field has been reduced and found that it is possible to improve the strength of the total exchange coupling magnetic field by making the film thickness uniform, thereby completing the present invention. It reached.

  In order to solve the above-described problems, according to an aspect of the present invention, a sputtering apparatus is used to form at least a first soft magnetic layer, a nonmagnetic spacer layer, a first soft magnetic layer, and an anti-strength on a disk substrate. In the method for manufacturing a perpendicular magnetic recording disk in which the second soft magnetic layer forming the magnetic exchange coupling (AFC) structure and the magnetic recording layer are formed in this order, the spacer layer is formed of a rare gas having an atomic radius larger than that of argon. A method of manufacturing a perpendicular magnetic recording disk is provided, wherein the film is formed in an atmosphere containing the perpendicular magnetic recording disk.

  In sputtering, ruthenium as a target is ionized and collided with a rare gas having a larger atomic radius than argon, so that the kinetic energy of atoms scattered from the target surface becomes higher than when argon is used as the rare gas, and migration occurs. This promotes uniform film thickness and reduced surface roughness. In this way, the homogenized soft magnetic layer does not have a domain wall, reduces the perpendicular component of the magnetization direction and spike noise, and can produce a high-quality reproduction signal.

  The rare gas may be krypton, xenon, or radon. Krypton (Kr), xenon (Xe), and radon (Rn) are all rare gases having an atomic radius larger than that of argon, and can be applied to the sputtering apparatus of the present invention.

  The spacer layer may be formed such that the exchange coupling magnetic field indicating the strength of antiferromagnetic exchange coupling has a peak thickness.

  There is a correlation between the thickness of the spacer layer and the exchange coupling magnetic field, and the exchange coupling magnetic field has a peak protruding with respect to a predetermined film thickness. Therefore, the film thickness at which the exchange coupling magnetic field reaches a peak can be uniquely selected. In the method for manufacturing a perpendicular magnetic recording disk according to the present invention, the spacer layer can be formed to have a uniform thickness, so that the exchange coupling magnetic field can be peaked over the entire surface of the perpendicular magnetic recording disk. Accordingly, it is possible to increase the SNR and improve the reproduction signal quality.

  In order to solve the above-described problems, according to another aspect of the present invention, there is provided a perpendicular magnetic recording disk manufactured using the above-described method for manufacturing a perpendicular magnetic recording disk.

  The components based on the technical idea of the method for manufacturing a perpendicular magnetic recording disk and the description thereof can be applied to the perpendicular magnetic recording disk.

  As described above, according to the method of manufacturing a perpendicular magnetic recording disk of the present invention, it is possible to increase the SNR by increasing the exchange coupling magnetic field of the soft magnetic layer and improve the reproduction signal quality.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In the present specification and drawings, components having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted. Note that dimensions, materials, and other specific numerical values shown in the following examples are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified.

(Perpendicular magnetic recording disk 100)
FIG. 1 is a cross-sectional view showing the structure of the perpendicular magnetic recording disk 100 according to the present embodiment. The perpendicular magnetic recording disk 100 includes a disk substrate 110, an adhesion layer 112, a first soft magnetic layer 114a, a spacer layer 114b, a second soft magnetic layer 114c, an orientation control layer 116, a first underlayer 118a, and a second underlayer 118b. , A miniaturization promoting layer 120, a first magnetic recording layer 122a, a second magnetic recording layer 122b, a continuous layer 124, a medium protective layer 126, and a lubricating layer 128. The first soft magnetic layer 114a, the spacer layer 114b, and the second soft magnetic layer 114c function together as the soft magnetic layer 114, and the first base layer 118a and the second base layer 118b function together as the base layer 118. The first magnetic recording layer 122a and the second magnetic recording layer 122b function as the magnetic recording layer 122 together.

  First, an amorphous aluminosilicate glass was formed into a disk shape by direct pressing to produce a glass disk. The glass disk was subjected to grinding, polishing, and chemical strengthening in order to obtain a smooth nonmagnetic disk substrate 110 made of a chemically strengthened glass disk.

  The disk substrate 110 is preferably non-magnetic glass. Specific examples include aluminosilicate glass, aluminoborosilicate glass, soda lime glass, and aluminosilicate glass is particularly preferable. Since the aluminosilicate glass is smooth and has high rigidity, the magnetic spacing, particularly the flying height of the magnetic head, can be more stably reduced. Aluminosilicate glass can obtain high rigidity and strength by chemical strengthening. When the soft magnetic layer 114 is amorphous, the disk substrate 110 is also preferably made of amorphous glass.

  Subsequently, on the obtained disk substrate 110, a DC magnetron sputtering apparatus is used as the sputtering apparatus 200 as a vacuum film forming apparatus, and the deposition from the adhesion layer 112 to the continuous layer 124 is sequentially performed. The film was formed by a CVD (Chemical Vapor Deposition) apparatus as a film forming apparatus. Thereafter, the lubricating layer 128 was formed by dip coating. Note that it is also preferable to use an in-line film forming method in terms of high mass productivity. Hereinafter, the configuration of the sputtering apparatus, the configuration of each layer, and the manufacturing method will be described.

  FIG. 2 is an explanatory diagram illustrating the configuration of the sputtering apparatus 200 according to the present embodiment. A sputtering apparatus 200 shown in FIG. 2 includes a chamber 202 that forms a vacuum chamber, an introduction port 204 that is provided in the chamber 202 and introduces a rare gas from the outside, an exhaust port 206 for evacuating the chamber 202, and a disk. The carrier 208 that holds the base 110, the target 210 that is a film forming material for forming the disk base 110, and the film forming material that is released from the target 210 are focused on the disk base 110, and are scattered to other than the disk base 110. It includes a shield 212 for preventing, and a magnet 214 for increasing the film formation speed and performing low-temperature film formation.

  In film formation from the adhesion layer 112 to the continuous layer 124 using the sputtering apparatus 200, first, plasma is generated between the target 210 and the shield 212 in the chamber 202. Then, noble gas ions generated by the plasma are accelerated by an electric field and irradiated onto the target 210 made of a film forming material. The rare gas ions eject atoms or molecules on the surface of the target 210 from the surface. The ejected atoms and / or molecules of the film forming material are deposited on the disk substrate 110 to form a thin film (layer).

  Below, the structure and manufacturing method of each layer are explained in full detail.

  The adhesion layer 112 was formed using a Ti alloy target so as to be a 10 nm Ti alloy layer. By forming the adhesion layer 112, the adhesion between the disk substrate 110 and the soft magnetic layer 114 can be improved, so that the soft magnetic layer 114 can be prevented from peeling off. As a material of the adhesion layer 112, for example, a CrTi alloy can be used. From the practical viewpoint, the thickness of the adhesion layer is preferably 1 nm to 50 nm.

  The soft magnetic layer 114 has an AFC (Antiferro-magnetic exchange coupling) by interposing a nonmagnetic spacer layer 114b between the first soft magnetic layer 114a and the second soft magnetic layer 114c. It was configured to provide. Thereby, the magnetization direction of the soft magnetic layer 114 can be aligned along the magnetic path (magnetic circuit) with high accuracy. Thus, since the perpendicular component of the magnetization direction is extremely reduced, noise generated from the soft magnetic layer 114 can be reduced.

  FIG. 3 is an explanatory diagram for explaining the magnetization characteristics of the AFC structure. Referring to such magnetization characteristics, a soft magnetic layer having no AFC structure maintains a positive or negative magnetization state when an external magnetic field H is not applied, whereas a soft magnetic layer having an AFC structure has a magnetic field H Is not applied, a magnetic flux is formed between the first soft magnetic layer 114a and the second soft magnetic layer 114c as shown in (b), and the magnetization M becomes zero. When a magnetic field H is applied in either direction, the magnetic fluxes of both soft magnetic layers 114a and 114c are oriented in the same direction as indicated by arrows (a) and (c).

  The coupling strength of the AFC structure is determined based on the exchange coupling magnetic field (Hex) shown in FIG. 3, and the larger the exchange coupling magnetic field, the stronger the coupling (exchange coupling) of AFC. The exchange coupling magnetic field is set so as to be magnetized with respect to the magnetic field for writing of the corresponding magnetic recording layer 122 and not to react with the magnetic field for writing of the adjacent magnetic recording layer 122.

  In the present embodiment, FeCoTaZr is used as the composition of the first soft magnetic layer 114a and the second soft magnetic layer 114c, and ruthenium (Ru) is used as the composition of the spacer layer 14b, but the first soft magnetic layer 114a and the second soft magnetic layer 114c are used. The composition of the soft magnetic layer 114c is not particularly limited. For example, a CoFe alloy (FeCoB, FeCoSiB, FeCoZr, FeCoCrB, FeCoZrB, etc.), an Fe alloy (FeTaN, FeTaC, etc.), a Co alloy (CoTaZr, CoZrNb, CoB, etc.). ) Etc. can be used. The total thickness of the soft magnetic layer 114 is 20 nm to 120 nm, preferably 30 nm to 100 nm.

  Further, as described above, the soft magnetic layer 114 is formed by sputtering. In such sputtering, argon (Ar) is generally used as a rare gas, but at least when the spacer layer 114b is formed, krypton (Kr), xenon (Xe), radon (having an atomic radius larger than argon) is used. Rn) is used. Accordingly, a rare gas having an atomic radius larger than that of argon may be used in forming all of the first soft magnetic layer 114a, the spacer layer 114b, and the second soft magnetic layer 114c constituting the soft magnetic layer 114, or the first soft magnetic layer may be used. Argon may be used for the layer 114a and the second soft magnetic layer 114c, and a rare gas having an atomic radius larger than argon may be used only for the spacer layer 114b.

  The object of the present embodiment can be achieved by using a rare gas having an atomic radius larger than that of argon for at least the spacer layer 114b. Therefore, by changing the rare gas only in the spacer layer 114b, it is possible to avoid unnecessary wasteful gas emission. Cost reduction can be achieved.

  Further, there is a correlation between the film thickness of the spacer layer 114b and the exchange coupling magnetic field, and the exchange coupling magnetic field has a peak protruding with respect to a predetermined film thickness. Therefore, the spacer layer 114b is formed so as to have a film thickness at which the exchange coupling magnetic field reaches a peak.

FIG. 4 is an explanatory diagram showing the relationship between the film thickness of the spacer layer 114b and the exchange coupling magnetic field. The exchange coupling magnetic field Hex draws a locus as shown in FIG. 4 with respect to the film thickness of ruthenium (Ru) by RKKY (Ruderman-Kittel-Kasuya-Yosida) interaction. Here, the exchange coupling magnetic field forming the spacer layer 114b so that the thickness _{t 0} of the peak _{Hex max.} The film thickness of the spacer layer 114b is based on the fact that the film formation processing time and the film thickness are in a proportional relationship. For example, when it takes 100 seconds to form the film thickness of 60 nm, the film thickness of 0.6 nm In order to form the thickness, the film formation processing time is adjusted to 1 second.

However, even if deposited spacer layer 114b to a thickness t _0, the thickness of the used when the surface direction argon Ar becomes uneven as the rare gas, for example, only the deviation t _d component of FIG. 4 unevenness Occurs.

In particular, when the locus around the peak protrudes as shown in FIG. 4, the attenuation from the peak of the exchange coupling magnetic field with respect to the deviation t _d is large regardless of whether the film thickness is thicker or thinner than the desired thickness. As a result, the total exchange coupling magnetic field is significantly reduced.

  In this embodiment, in sputtering, a rare gas having a larger atomic radius than argon, for example, krypton is ionized and collided with ruthenium as a target, so that atoms jump out from the target surface more than when argon is used as the rare gas. The kinetic energy (movement speed) of the atoms is easily increased, and the migration of the atoms deposited on the disk substrate 110 irregularly on the disk substrate 110 is increased. By such migration, atoms move to a stable position, and the film thickness can be made uniform and the surface roughness can be reduced.

When the film thickness is uniform, reduced deviation t _d of FIG. 4, the exchange coupling magnetic field in the entire surface of the disk base is close to the peak Hex _max. Therefore, the soft magnetic layer 114 generally improves the strength of the exchange coupling magnetic field, does not form a domain wall, reduces the perpendicular component of the magnetization direction and spike noise, and can produce a high-quality reproduction signal. .

  The orientation control layer 116 has a function of protecting the soft magnetic layer 114 and a function of promoting alignment of crystal grain orientations of the underlayer 118. The material of the orientation control layer 116 can be selected from Ni, Cu, Pt, Pd, Zr, Hf, and Nb. Furthermore, it is good also as an alloy which contains these metals as a main component and contains any one or more additional elements of Ti, V, Ta, Cr, Mo, and W. For example, NiW, CuW, or CuCr can be suitably selected.

  The underlayer 118 has an hcp structure, and the crystal of the hcp structure of the magnetic recording layer 122 can be grown as a granular structure. Therefore, the higher the crystal orientation of the underlayer 118, the more the orientation of the magnetic recording layer 122 can be improved. The material of the underlayer can be selected from RuCr and RuCo in addition to Ru. Ru has an hcp structure and can satisfactorily orient a magnetic recording layer containing Co as a main component.

  In the present embodiment, the base layer 118 has a two-layer structure made of Ru. When forming the second base layer 118b on the upper layer side, the Ar gas pressure is set higher than when forming the first base layer 118a on the lower layer side. When the gas pressure is increased, the free movement distance of the plasma ions to be sputtered is shortened, so that the film formation rate is reduced and the crystal orientation can be improved. Further, by increasing the pressure, the size of the crystal lattice is reduced. Since the size of the Ru crystal lattice is larger than that of the Co crystal lattice, if the Ru crystal lattice is made smaller, it approaches that of Co, and the crystal orientation of the Co granular layer can be further improved.

The miniaturization promoting layer 120 is a nonmagnetic granular layer. A nonmagnetic granular layer is formed on the hcp crystal structure of the underlayer 118, and the granular layer of the first magnetic recording layer 122a is grown thereon, so that the magnetic granular layer can be grown from the initial growth stage (rise). Has the effect of separating. The composition of the miniaturization promoting layer 120 was nonmagnetic CoCr—SiO ₂ .

  The magnetic recording layer 122 includes a thin first magnetic recording layer 122a and a thick second magnetic recording layer 122b.

The first magnetic recording layer 122a is a 2 nm CoCrPt—Cr ₂ O ₃ hcp crystal structure using a hard magnetic target made of CoCrPt containing chromium oxide (Cr ₂ O ₃ ) as an example of a nonmagnetic material. Formed. Nonmagnetic substances segregated around the magnetic substance to form grain boundaries, and the magnetic grains (magnetic grains) formed columnar granular structures. The magnetic grains were epitaxially grown continuously from the granular structure of the miniaturization promoting layer.

The second magnetic recording layer 122b has a 10 nm CoCrPt—TiO ₂ hcp crystal structure using a hard magnetic target made of CoCrPt containing titanium oxide (TiO ₂ ) as an example of a nonmagnetic material. . Also in the second magnetic recording layer 122b, the magnetic grains formed a granular structure.

  Here, the atmospheric gas pressure of the first magnetic recording layer 122a was set to a high pressure of 3 Pa to 10 Pa. Thus, high Hc and Hn could be obtained by forming a film using a high-pressure atmospheric gas. The atmospheric gas pressure of the second magnetic recording layer 122b was set to a low pressure of 0.6 Pa to 3 Pa. Thus, high impact resistance was able to be obtained by forming into a film using low pressure atmospheric gas.

In the present embodiment, different materials (targets) are used for the first magnetic recording layer 122a and the second magnetic recording layer 122b, but it is not necessary to use different materials, and even if the materials are the same in composition and type. Good. Examples of the nonmagnetic material for forming the nonmagnetic region include silicon oxide (SiO _x ), chromium (Cr), chromium oxide (CrO _x ), titanium oxide (TiO ₂ ), zircon oxide (ZrO ₂ ), and oxide. An example is tantalum (Ta ₂ O ₅ ).

  The continuous layer 124 forms a thin film (auxiliary recording layer) exhibiting high perpendicular magnetic anisotropy on the granular magnetic layer to constitute a CGC structure (Coupled Granular Continuous). Thereby, in addition to the high density recording property and low noise property of the granular layer, the high heat resistance of the continuous film can be added. The composition of the continuous layer 124 was CoCrPtB.

The medium protective layer 126 is formed by depositing carbon by CVD while maintaining a vacuum and including diamond-like carbon. The medium protective layer 126 is a protective layer for protecting the perpendicular magnetic recording layer from the impact of the magnetic head. In general, carbon deposited by the CVD method has improved film hardness compared to that deposited by the sputtering method, so that the perpendicular magnetic recording layer can be protected more effectively against the impact from the magnetic head. For the medium protective layer 126, for example, a material such as C, SiO ₂ or ZrO ₂ can be used. From the viewpoint of increasing the recording density, the thickness of the medium protective layer is preferably 1 nm or more and 5 nm or less.

  The lubricating layer 128 was formed of PFPE (perfluoropolyether) by dip coating. For example, a material such as fluorinated alcohol or fluorinated carboxylic acid can be used for the lubricating layer 128. The film thickness of the lubricating layer 128 is about 1 nm.

(Example)
Through the above manufacturing process, the perpendicular magnetic recording disk 100 was obtained. Hereinafter, the effectiveness of this embodiment will be described using an example of the perpendicular magnetic recording disk 100 generated by such a manufacturing process. Here, sputtering was performed using argon Ar and krypton Kr as rare gases, and the characteristics of the produced perpendicular magnetic recording disk 100 were compared.

  When the orientation of the magnetic recording layer 122 of the perpendicular magnetic recording disk 100 was analyzed by an X-ray diffraction method, it was oriented in a direction perpendicular to the surface of the perpendicular magnetic recording disk. Further, the surface roughness of the spacer layer 114b is measured with an AFM (atomic force microscope), the magnetic characteristics of the perpendicular magnetic recording disk 100, and the exchange coupling magnetic field Hex of the soft magnetic layer 114 with a magnetometer based on the transverse Kerr effect. evaluated. The evaluation results are shown in FIGS. FIG. 5 shows the dependence of the exchange coupling magnetic field on the thickness of the spacer layer, and FIG. 6 shows the magnetic characteristics of the perpendicular magnetic recording disk and the exchange coupling magnetic field of the soft magnetic layer. Comparing argon Ar and krypton Kr in FIG. 6, it can be understood that krypton Kr has improved surface roughness of the spacer layer 114 b and the exchange coupling magnetic field Hex in the soft magnetic layer 114.

  Although the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such examples. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  The present invention can be used as a method of manufacturing a perpendicular magnetic recording disk mounted on an HDD or the like and as a perpendicular magnetic recording disk.

1 is a cross-sectional view showing the structure of a perpendicular magnetic recording disk according to an embodiment. It is explanatory drawing explaining the structure of the sputtering device concerning this embodiment. It is explanatory drawing for demonstrating the magnetization characteristic by an AFC structure. It is explanatory drawing which showed the relationship between the film thickness of a spacer layer, and an exchange coupling magnetic field. It is explanatory drawing which showed the film thickness dependence of the spacer layer of the exchange coupling magnetic field. FIG. 5 is an evaluation diagram showing the magnetic characteristics of a perpendicular magnetic recording disk and the exchange coupling magnetic field of a soft magnetic layer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Perpendicular magnetic recording disk 110 ... Disk base | substrate 114 ... Soft magnetic layer 114a ... 1st soft magnetic layer 114b ... Spacer layer 114c ... 2nd soft magnetic layer 122 ... Magnetic recording layer 122a ... 1st magnetic recording layer 122b ... 2nd magnetic Recording layer 200 ... Sputtering apparatus

Claims (4)

Using a sputtering apparatus, at least a first soft magnetic layer, a nonmagnetic spacer layer, and a second soft magnetic layer that forms an antiferromagnetic exchange coupling (AFC) structure with the first soft magnetic layer on the disk substrate; In the method of manufacturing a perpendicular magnetic recording disk in which the magnetic recording layers are formed in this order,
The method of manufacturing a perpendicular magnetic recording disk, wherein the spacer layer is formed in an atmosphere containing a rare gas having an atomic radius larger than argon.   2. The method of manufacturing a perpendicular magnetic recording disk according to claim 1, wherein the rare gas is any one of krypton, xenon, and radon.   3. The perpendicular magnetic recording according to claim 1, wherein the spacer layer is formed so as to have a film thickness at which an exchange coupling magnetic field indicating the strength of the antiferromagnetic exchange coupling has a peak. Disc manufacturing method.   A perpendicular magnetic recording disk manufactured using the method for manufacturing a perpendicular magnetic recording disk according to claim 1.

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