JP2010199192A - Perpendicular magnetic recording medium, recording device, and multilayer structure film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multilayer structure film that can greatly contribute to the thin filming of a multilayer magnetic layer. <P>SOLUTION: One concrete example of the multilayer structure film includes: a laminate 41 formed by alternately laminating first thin films 43a made from non-magnetic noble metal atoms and second thin films 43b made from magnetic atoms or a magnetic alloy; and a ferromagnetic film 42 laminated on a surface of the laminate 41, having a saturation magnetization Ms larger than a saturation magnetization Ms of the laminate 41. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a so-called perpendicular magnetic storage medium and a multilayer structure film.

  So-called bit patterned media is widely known. In bit patterned media, a plurality of rows of recording tracks extend concentrically on the surface of the recording magnetic layer. For example, magnetic pillars are arranged in one or more rows in each recording track. The magnetic pillars are magnetically separated from each other by the action of a non-magnetic material. In realizing perpendicular magnetic recording, a recording magnetic layer is laminated on a soft magnetic backing layer. The magnetic field leaking from the write head penetrates the recording magnetic layer perpendicular to the surface of the recording magnetic layer by the action of the backing layer.

JP 2001-101463 A JP 2001-331919 A

  Multilayer magnetic layers of palladium and cobalt layers are widely known. In bit patterned media, the use of such multilayer magnetic layers is sought. For use, it is required to reduce the thickness of the multilayer magnetic layer. When thinning is realized, the magnetic field leaking from the write head surely reaches the backing layer. A strong magnetic field can surely act on the multilayer magnetic layer during writing.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a multilayer structure film that can greatly contribute to the reduction of the thickness of the multilayer magnetic layer. It is an object of the present invention to provide a perpendicular magnetic storage medium using such a multilayer structure film.

  In order to achieve the above object, one specific example of the multilayer structure film includes a first thin film formed from nonmagnetic noble metal atoms, and a laminate in which a second thin film formed from magnetic atoms or a magnetic alloy is overlaid, A ferromagnetic film superposed on the surface of the laminate and having a saturation magnetization larger than that of the laminate.

  In such a multilayer structure film, the entire saturation magnetization can be adjusted by the action of the ferromagnetic film. The film thickness of the thin film can be set as a discrete value, that is, an increase / decrease value about the size of an atom. The thickness of the thin film need not be finely adjusted at a level smaller than the size of the atoms. As a result, a desired value of saturation magnetization can be established relatively easily even if the laminate is thinned.

  Such a multilayer structure film can be used for a perpendicular magnetic storage medium. At this time, the perpendicular magnetic storage medium is superimposed on the substrate, the soft magnetic backing layer laminated on the surface of the substrate, the nonmagnetic intermediate layer laminated on the surface of the backing layer, and the nonmagnetic intermediate layer. A laminated body in which a first thin film formed from a nonmagnetic noble metal atom and a second thin film formed from a magnetic atom or a magnetic alloy are superposed on each other, and is superposed on the surface of the laminated body to saturate the laminated body A ferromagnetic film having a saturation magnetization larger than the magnetization may be provided.

  Such perpendicular magnetic storage media can be used in storage devices. The storage device includes a storage medium and a head slider that faces the surface of the storage medium. The storage medium includes a substrate, a soft magnetic backing layer laminated on the surface of the substrate, and the backing layer. A nonmagnetic intermediate layer laminated on the surface, a first thin film formed from a nonmagnetic noble metal atom, and a second thin film formed from a magnetic atom or a magnetic alloy are overlaid on the nonmagnetic intermediate layer. What is necessary is just to provide a laminated body and a ferromagnetic film that is superposed on the surface of the laminated body and has a saturation magnetization larger than that of the laminated body.

  As described above, according to the disclosed structure, a multilayer structure film that can greatly contribute to thinning of the multilayer magnetic layer is provided.

It is a top view which shows the internal structure of the memory | storage device which concerns on one Embodiment, ie, a hard-disk drive (HDD). 2 is an enlarged perspective view schematically showing a surface of a magnetic disk. FIG. FIG. 3 is a vertical sectional view taken along line 3-3 in FIG. 2 and is a vertical sectional view showing the magnetic disk according to the first embodiment. It is the elements on larger scale of the vertical sectional view of FIG. FIG. 4 is a vertical sectional view schematically showing a resist film formed on the surface of the ferromagnetic film in the course of demagnetization of the laminated body and the ferromagnetic film, corresponding to FIG. 3. It is a graph which shows the relationship between the film thickness of a ferromagnetic film, saturation magnetization, and a uniaxial anisotropic magnetic field, respectively. FIG. 4 is a vertical sectional view corresponding to FIG. 3 and showing a magnetic disk according to a second embodiment.

  Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 schematically shows an internal structure of a storage device, that is, a hard disk drive (HDD) 11 according to a specific example. The HDD 11 includes a housing, that is, a housing 12. The housing 12 includes a box-shaped base 13 and a cover (not shown). The base 13 defines, for example, a flat rectangular parallelepiped internal space, that is, an accommodation space. The cover is coupled to the opening of the base 13. The accommodation space is sealed between the cover and the base 13.

  A specific example of the storage medium, that is, one or more magnetic disks 14 are stored in the storage space. The magnetic disk 14 is mounted on the rotation shaft of the spindle motor 15. The spindle motor 15 can rotate the magnetic disk 14 at a high speed such as 5400 rpm, 7200 rpm, 10000 rpm, and 15000 rpm. As will be described later, each magnetic disk 14 is configured as a so-called perpendicular magnetic storage medium.

  A carriage 16 is further accommodated in the accommodation space. The carriage 16 includes a carriage block 17. The carriage block 17 is rotatably connected to a support shaft 18 that rises vertically from the bottom plate of the base 13. A plurality of carriage arms 19 extending in the horizontal direction from the support shaft 18 are defined in the carriage block 17.

  A head suspension 21 is attached to the tip of each carriage arm 19. The head suspension 21 extends forward from the tip of the carriage arm 19. A flexure is attached to the head suspension 21. A flying head slider 22 is supported on the flexure. Based on the flexure, the flying head slider 22 can change its posture with respect to the head suspension 21. A head element, that is, an electromagnetic conversion element (not shown) is mounted on the flying head slider 22.

  The electromagnetic conversion element includes a write head element and a read head element. A so-called single pole head is used for the write head element. A single pole head generates a magnetic field by the action of a thin film coil pattern. The magnetic field circulates through the single pole head and the magnetic disk 14 by the action of the main pole and the sub pole. Due to the circulation, a magnetic field is induced in the vertical direction perpendicular to the surface of the magnetic disk 14. Information is written to the magnetic disk 14 by the action of the magnetic field. On the other hand, a giant magnetoresistance effect (GMR) element or a tunnel junction magnetoresistance effect (TMR) element is used for the read head element. In the GMR element and the TMR element, the resistance change of the spin valve film and the tunnel junction film is caused according to the direction of the magnetic field acting from the magnetic disk 14. Information is read from the magnetic disk 14 based on such resistance change.

  When an air flow is generated on the surface of the magnetic disk 14 based on the rotation of the magnetic disk 14, positive pressure, that is, buoyancy and negative pressure act on the flying head slider 22 by the action of the air flow. The buoyancy balances with the negative pressure and the pressing force of the head suspension 21. As a result, the flying head slider 22 can continue to fly with relatively high rigidity while the magnetic disk 14 is rotating.

  A voice coil motor (VCM) 23 is connected to the carriage block 17. The carriage block 17 can rotate around the support shaft 18 by the action of the voice coil motor 23. Based on the rotation of the carriage block 17, the swing of the carriage arm 19 and the head suspension 21 is realized. When the carriage arm 19 swings around the support shaft 18 during the flying of the flying head slider 22, the flying head slider 22 can move along the radial line of the magnetic disk 14. As a result, the electromagnetic transducer on the flying head slider 22 can cross the data zone between the innermost recording track and the outermost recording track. Based on such movement of the flying head slider 22, the electromagnetic transducer is positioned with respect to the target recording track.

  A load tab 24 extending forward from the tip of the head suspension 21 is defined at the tip of the head suspension 21. The load tab 24 can move in the radial direction of the magnetic disk 14 based on the swing of the carriage arm 19. A ramp member 25 is disposed outside the magnetic disk 14 on the moving path of the load tab 24. The lamp member 25 is fixed to the base 13. The load tab 24 is received by the ramp member 25.

  The ramp member 25 is formed with a ramp 25 a extending along the movement path of the load tab 24. The ramp 25a moves away from a virtual plane including the surface of the magnetic disk 14 as the distance from the center of the magnetic disk 14 increases. Therefore, when the carriage arm 19 moves away from the rotation axis of the magnetic disk 14 around the support shaft 18, the load tab 24 goes up the ramp 25a. Thus, the flying head slider 22 is peeled off from the surface of the magnetic disk 14. The flying head slider 22 is retracted from the magnetic disk 14 to the outside. On the other hand, when the carriage arm 19 swings around the support shaft 18 toward the rotation axis of the magnetic disk 14, the load tab 24 moves down the ramp 25a. Buoyancy acts on the flying head slider 22 from the rotating magnetic disk 14. The ramp member 25 and the load tab 24 cooperate to constitute a so-called load / unload mechanism.

  As shown in FIG. 2, a plurality of rows of magnetic dots 26 are established concentrically on the surface of the magnetic disk 14. Each magnetic dot 26 is formed of a cylinder having a central axis perpendicular to the surface of the magnetic disk 14, that is, a magnetic pillar. The diameter of the magnetic pillar is set to about 20 nm, for example. The distance between the central axes is set to about 22 nm to 23 nm, for example. The magnetic pillars are separated by a nonmagnetic material 27. Here, for example, one recording track 28 is formed by three columns of magnetic pillars. Therefore, the recording tracks 28 are magnetically separated by the nonmagnetic material 27. In addition, the magnetic pillars are individually separated by the nonmagnetic material 27 in each row.

FIG. 3 shows a cross-sectional structure of the magnetic disk 14 according to an embodiment of the present invention. The magnetic disk 14 includes a base, that is, a substrate 31. The substrate 31 may be composed of, for example, a disk-shaped Si main body 31a and an amorphous SiO ₂ film 31b spreading on the front and back surfaces of the Si main body 31a. Here, only the surface of the Si body 31a is shown. In addition, a glass substrate or an aluminum substrate may be used for the substrate 31.

  A backing layer 32 spreads on the surface of the substrate 31. The backing layer 32 may be made of a soft magnetic material such as a FeTaC film or a NiFe film. Here, for example, an FeTaC film having a thickness of about 300 [nm] is used. In the backing layer 32, the easy axis of magnetization is established in the in-plane direction defined parallel to the surface of the substrate 31.

  A multilayer structure film 33 spreads on the surface of the backing layer 32. Magnetic information is recorded in the multilayer structure film 33. The surface of the multilayer structure film 33 is covered with a protective film 34 such as a diamond-like carbon (DLC) film and a lubricating film 35 such as a perfluoropolyether (PFPE) film. Similarly, a backing layer 32, a multilayer structure film 33, a protective film 34, and a lubricating film 35 are sequentially laminated on the back surface of the substrate 31.

  The multilayer structure film 33 includes a tantalum (Ta) adhesion layer 37 extending on the surface of the backing layer 32. The tantalum adhesion layer 37 is overlaid on the surface of the backing layer 32. The tantalum adhesion layer 37 has an amorphous structure. The film thickness of the tantalum adhesion layer 37 is set to 2.0 [nm], for example.

  A palladium (Pd) underlayer 38 spreads on the surface of the tantalum adhesion layer 37. The palladium underlayer 38 is overlaid on the surface of the tantalum adhesion layer 37. The palladium underlayer 38 has a polycrystalline structure. Adjacent crystals adhere to each other. The film thickness of the palladium underlayer 38 is set to less than 5.0 [nm]. Here, the film thickness of the palladium underlayer 38 is set to 3.0 [nm]. The tantalum adhesion layer 37 and the palladium underlayer 38 function as a nonmagnetic intermediate layer.

  The multilayer structure film 33 includes a stacked body 41 that spreads on the surface of the palladium base layer 38. A ferromagnetic film 42 is overlaid on the surface of the stacked body 41. The ferromagnetic film 42 is received directly on the surface of the multilayer body 41. The magnetic pillar described above is formed in the laminate 41 and the ferromagnetic film 42.

  FIG. 4 shows a specific example of the laminated body 41. The stacked body 41 includes at least one layer of a two-layer structure film 43. Each two-layer structure film 43 includes a first thin film 43a having a first film thickness and a second thin film 43b having a second film thickness superimposed on the first thin film 43a. The second thin film 43b is received directly on the surface of the first thin film 43a. The second thin film 43b is in close contact with the surface of the first thin film 43a. The first thin film 43a is formed from nonmagnetic noble metal atoms. The nonmagnetic noble metal atom is composed of, for example, a palladium (Pd) atom. Therefore, the first thin film 43a forms a palladium layer. The magnetic atom is composed of, for example, a cobalt (Co) atom. Therefore, the second thin film 43b forms a cobalt layer. In addition, platinum (Pt) atoms may be used instead of palladium atoms. Here, the laminated body 41 includes a two-layer structure film 43 of five layers. In the two-layer structure film 43, a palladium layer having a thickness of 0.2 [nm], that is, a second thin film 43b is directly superimposed on a surface of the palladium layer having a thickness of 0.8 [nm], that is, the first thin film 43a. Such a two-layer structure film 43 a establishes an easy magnetization axis perpendicular to the surface of the substrate 31 in the stacked body 41. The film thickness of the first thin film 43a and the film thickness of the second thin film 43b may be set as appropriate. The saturation magnetization Ms and the uniaxial anisotropic magnetic field Hk of the stacked body 41 can be adjusted according to the adjustment of the film thickness.

  The ferromagnetic film 42 is in close contact with the surface of the outermost second thin film 43b. The ferromagnetic film 42 is formed from a cobalt platinum base alloy. That is, the ferromagnetic film 42 contains cobalt atoms and platinum atoms. It is desirable that the cobalt platinum-based alloy contains chromium atoms. Based on the addition of chromium atoms, the crystal lattice can be arranged in cobalt platinum based alloys. The saturation magnetization Ms of the ferromagnetic film 42 is set larger than the saturation magnetization Ms of the stacked body 41. In such setting, the content of platinum atoms (and chromium atoms) may be adjusted in the cobalt platinum-based alloy. At the same time, the uniaxial anisotropic magnetic field Hk of the laminate 41 and the ferromagnetic film 42 is set larger than the uniaxial anisotropic magnetic field unique to the ferromagnetic film 42. In such setting, as described later, the film thickness of the ferromagnetic film 42 is adjusted.

  Now, when the write head element, that is, the single magnetic pole head is faced to the surface of the magnetic disk 14, the magnetic field leaking from the main magnetic pole acts on the laminated body 41 and the ferromagnetic film 42 by the magnetic dots 26. A magnetic field is induced in the stacked body 41 and the ferromagnetic film 42 in a direction perpendicular to the surfaces of the stacked body 41 and the ferromagnetic film 42. The magnetic field circulates from the backing layer 32 to the secondary pole of the single pole head. In this way, in the multilayer body 41 and the ferromagnetic film 42, upward (vertical outward) magnetization or downward (vertical inward) magnetization is established for each of the plurality of magnetic pillars. Information is recorded. At this time, since the total film thickness of the tantalum adhesion layer 37, the palladium underlayer 38, the stacked body 41, and the ferromagnetic film 42 is sufficiently reduced, the distance between the single pole head and the backing layer 32 can be reduced. . As a result, a sufficiently strong magnetization can be established in the stacked body 41 and the ferromagnetic film 42. As will be described later, the laminated body 41 and the ferromagnetic film 42 ensure a precisely adjusted uniaxial anisotropy magnetic field Hk, so that accurate information can be written with a small magnetic field. .

  When the read head element faces the surface of the magnetic disk 14, the magnetic field leaking from the stacked body 41 and the ferromagnetic film 42 acts on the spin valve film and the tunnel junction film. A resistance change of the spin valve film or the tunnel junction film is caused. Information is read from the magnetic disk 14 based on such resistance change. At this time, in the stacked body 41 and the ferromagnetic film 42, as will be described later, a saturation magnetization Ms larger than the saturation magnetization Ms of the stacked body 41 alone is secured by the action of the ferromagnetic film 42. Thus, the leaking magnetic field can be increased. In addition, since the accurately adjusted uniaxial anisotropic magnetic field Hk is ensured, the thermal fluctuation resistance of the recording magnetization can be sufficiently ensured. Certainly accurate information can be restored.

  Next, a method for manufacturing the magnetic disk 14 will be briefly described. First, the substrate 31 is prepared. The substrate 31 is mounted on a sputtering apparatus. A vacuum environment is established in the chamber of the sputtering apparatus. For example, an FeTaC target is set in the chamber. A backing layer 32 is formed on the surface of the substrate 31 in the chamber. A tantalum adhesion layer 37 having a thickness of 2.0 [nm] and a palladium underlayer 38 having a thickness of 3.0 [nm] are sequentially formed on the surface of the backing layer 32. A sputtering apparatus is used for the formation. Similarly, a tantalum target or a palladium target is set in the sputtering apparatus. In forming the palladium underlayer 38, for example, the pressure in the chamber is set to about 0.7 [Pa]. As a result, the crystal grains adhere to each other in the formed palladium underlayer 38. A polycrystalline film having a continuous structure is formed. On the other hand, when the pressure in the chamber is set to a high pressure of 7 [Pa], for example, crystal grains are separated from each other in the palladium underlayer 38. A polycrystalline film having a separation structure is formed.

  Thereafter, a laminate 41 is formed on the surface of the palladium underlayer 38. Five layers of a two-layer structure film 43 are laminated. A palladium layer having a thickness of 0.8 [nm] and a cobalt layer having a thickness of 0.2 [nm] are sequentially formed. A sputtering apparatus is used for the formation. A palladium target and a cobalt target are set in the chamber of the sputtering apparatus. A predetermined waiting time is secured prior to the formation of the cobalt layer after the formation of the palladium layer. In stacking the palladium layer, the sputtering rate is set to a rate slower than the sputtering rate set in stacking the palladium underlayer 38.

  A ferromagnetic film 42 is formed on the surface of the multilayer body 41. For example, a cobalt chromium platinum (CoCrPt) alloy having a film thickness of 2.0 [nm] is laminated. However, as will be described later, the film thickness of the cobalt chromium platinum alloy may be appropriately set in the range of 0 [nm] to 7.0 [nm] (not including “0 (zero)”). A sputtering apparatus is used for the formation. A cobalt chromium platinum target is set in the chamber of the sputtering apparatus. Thus, the ferromagnetic film 42 of cobalt platinum base alloy is laminated on the second thin film 43b of cobalt based on sputtering, so that the crystal lattice is adjusted by the ferromagnetic film 42. The orientation is enhanced. As a result, the saturation magnetization Ms is increased.

  Thereafter, as shown in FIG. 5, a resist film 46 is formed in a predetermined pattern on the surface of the ferromagnetic film 42. The resist film 46 covers an area corresponding to the magnetic dot 26 described above. For forming such a resist film 46, for example, a photolithography technique is used. After the resist film 46 is formed, ion implantation is performed on the surface of the ferromagnetic film 42. In the ion implanter, the arrival depth of ions is adjusted based on voltage control. As a result, the first and ferromagnetic films 41 and 42 are made amorphous uniformly from the surface of the ferromagnetic film 42 to a depth of 5.0 nm around the resist film 46. According to this amorphization, the magnetism of the first and ferromagnetic films 42 is lost. Thus, the altered region, that is, the nonmagnetic material 27 is formed. A magnetic pillar is established immediately below the resist film 46. After the magnetic pillar is established, the resist film 46 is removed.

  Thereafter, a protective film 34 is formed on the surfaces of the stacked body 41 and the ferromagnetic film 42. For the formation, for example, a CVD method (chemical vapor deposition method) is used. A lubricating film 35 is applied to the surface of the protective film 34. A so-called dip method is used for application. In the dip method, the substrate 31 is immersed in a solution containing, for example, perfluoropolyether.

  The inventor has verified the characteristics of the multilayer structure film 33. Upon verification, a tantalum adhesion layer 37 having a thickness of 2.0 [nm] and a palladium underlayer 38 having a thickness of 3.0 [nm] were formed on a glass substrate. A laminate 41 and a ferromagnetic film 42 were formed on the palladium underlayer 38. In the two-layer structure film 43, a cobalt layer having a film thickness of 0.2 [nm] was laminated on a palladium layer having a film thickness of 0.8 [nm]. For the ferromagnetic film 42, for example, a cobalt chromium platinum (CoCrPt) alloy having a thickness of 2.0 [nm] was used. The content of cobalt atoms was set to 74.2 [atomic%]. The chromium atom content was set to 3.3 [atomic%]. The platinum atom content was set to 22.5 [at%]. Four specific examples were prepared. For each specific example, the film thickness of the ferromagnetic film 42 was set to 2.0 [nm], 3.0 [nm], 4.0 [nm], and 5.0 [nm]. The saturation magnetization Ms and the uniaxial anisotropic magnetic field Hk of the laminate 41 and the ferromagnetic film 42 were measured for each specific example. A reference example was prepared. In the first reference example, the ferromagnetic film 42 is omitted. Other structures were formed in the same manner as the specific examples. In the second reference example, the ferromagnetic film 42 is laminated on the ruthenium underlayer. Based on the first reference example, the saturation magnetization Ms and the uniaxial anisotropic magnetic field Hk specific to the laminate 41 were measured. Based on the second reference example, the saturation magnetization Ms and the uniaxial anisotropic magnetic field Hk specific to the ferromagnetic film 42 were measured.

  As shown in FIG. 6, it was confirmed that the saturation magnetization Ms is increased by the action of the ferromagnetic film 42. In addition, it was confirmed that the saturation magnetization Ms increases as the thickness of the ferromagnetic film 42 increases. It was confirmed that the magnitude of the saturation magnetization Ms is adjusted according to the setting of the film thickness of the ferromagnetic film 42. On the other hand, it has been confirmed that the uniaxial anisotropic magnetic field Hk decreases as the thickness of the ferromagnetic film increases. Moreover, since the uniaxial anisotropic magnetic field Hk of the laminated body 41 and the ferromagnetic film 42 does not fall below the uniaxial anisotropic magnetic field Hk of the ferromagnetic film 42 alone, the film thickness of the ferromagnetic film 42 is 7.0 [ It is easily imagined that the uniaxial anisotropy magnetic field Hk is maintained at a constant value above [nm]. As a result, it was found that the uniaxial anisotropic magnetic field Hk is adjusted when the film thickness of the ferromagnetic film 42 is 7.0 [nm] or less.

The inventor calculated the total saturation magnetization Ms of the laminate 41 and the ferromagnetic film 42 based on computer simulation. In the calculation, the saturation magnetization Ms of the cobalt layer was set to 1400 [emu / cm ³ ]. The saturation magnetization Ms of the cobalt chromium platinum remittance layer was set to 800 [emu / cm ³ ]. As shown in FIG. 6, a similarity was found between the verified value and the calculated value. As a result, it was confirmed that the calculated value based on the computer simulation is greatly useful in designing the magnetic disk 14.

  As shown in FIG. 7, the nonmagnetic material 27 described above may be formed of a nonmagnetic material embedded in a space 48 formed from the surface of the ferromagnetic film 42 in the stacked body 41 and the ferromagnetic film 42. In forming such a space 48, for example, reactive ion etching (RIE) is used. When performing reactive ion etching, a resist film 46 is formed on the surface of the ferromagnetic film 42 as described above. When the etching process is performed around the resist film 46, the above-described magnetic pillar is formed immediately below the resist film 46. Thereafter, the resist film 46 is removed. The space 48 is filled with a nonmagnetic material around the magnetic pillar. For example, sputtering is used for such filling. Nonmagnetic material on the magnetic pillar is removed. After filling with the nonmagnetic material, a protective film 34 and a lubricating film 35 are formed on the surfaces of the magnetic pillar and the nonmagnetic material.

  In the two-layer structure film 43 described above, a cobalt alloy containing cobalt as a main component may be used instead of cobalt, or a palladium alloy containing palladium as a main component may be used instead of palladium. In addition, platinum (Pt) or a platinum alloy mainly containing platinum may be used instead of palladium. For example, boron (B) may be further added to the cobalt platinum-based alloy. One bit is not necessarily established by a plurality of magnetic pillars, and one bit may be established by one magnetic pillar.

  The applicant further discloses the following supplementary notes regarding the above embodiment.

  (Additional remark 1) The 1st thin film formed from a nonmagnetic noble metal atom, and the laminated body which repeatedly superimposes the 2nd thin film formed from a magnetic atom or a magnetic alloy, are piled up on the surface of the said laminated body, and the said lamination | stacking And a ferromagnetic film having a saturation magnetization larger than the saturation magnetization of the body.

  (Additional remark 2) The multilayer structure film of Additional remark 1 WHEREIN: The laminated body and the uniaxial anisotropic magnetic field of the said ferromagnetic film are set larger than the uniaxial anisotropic magnetic field intrinsic | native to the said ferromagnetic film, It is characterized by the above-mentioned. Multi-layer structure film.

  (Appendix 3) The multilayer structure film according to appendix 1 or 2, wherein the magnetic atom is cobalt.

  (Appendix 4) The multilayer structure film according to any one of appendices 1 to 3, wherein the nonmagnetic noble metal atom is palladium.

  (Additional remark 5) The multilayer structural film of Additional remark 4 WHEREIN: The said ferromagnetic film is formed from the alloy containing a cobalt atom and a platinum atom, The multilayer structure film characterized by the above-mentioned.

  (Additional remark 6) The multilayered structural film of Additional remark 5 WHEREIN: The said alloy further contains a chromium atom, The multilayered structural film characterized by the above-mentioned.

  (Additional remark 7) The multilayered structural film of Additional remark 6 WHEREIN: The film thickness of the said ferromagnetic film is set to 7.0 nm or less, The multilayered structure film characterized by the above-mentioned.

  (Appendix 8) The multilayer structure film according to any one of appendices 1 to 7, wherein the ferromagnetic film is superposed on a surface of the second thin film.

  (Supplementary Note 9) A substrate, a soft magnetic backing layer laminated on the surface of the substrate, a nonmagnetic intermediate layer laminated on the surface of the backing layer, and a nonmagnetic noble metal laminated on the nonmagnetic intermediate layer A laminated body in which a first thin film formed from atoms and a second thin film formed from a magnetic atom or a magnetic alloy are repeatedly superposed on each other, and is superposed on the surface of the laminated body, and is larger than the saturation magnetization of the laminated body A perpendicular magnetic storage medium comprising: a ferromagnetic film having saturation magnetization.

  (Supplementary note 10) In the multilayer structure film according to supplementary note 9, the uniaxial anisotropic magnetic field of the stacked body and the ferromagnetic film is set larger than the uniaxial anisotropic magnetic field unique to the ferromagnetic film, Multi-layer structure film.

  (Appendix 11) The multilayer structure film according to appendix 9 or 10, wherein the magnetic atom is cobalt.

  (Additional remark 12) The multilayer structural film of any one of Additional remarks 9-11 WHEREIN: The said nonmagnetic noble metal atom is palladium, The multilayer structural film characterized by the above-mentioned.

  (Additional remark 13) The multilayer structural film of Additional remark 12 WHEREIN: The said ferromagnetic film is formed from the alloy containing a cobalt atom and a platinum atom, The multilayer structure film characterized by the above-mentioned.

  (Appendix 14) The multilayer structure film according to appendix 13, wherein the alloy further contains a chromium atom.

  (Additional remark 15) The multilayered structure film of Additional remark 14 WHEREIN: The film thickness of the said ferromagnetic film is set to 7.0 nm or less, The multilayered structure film characterized by the above-mentioned.

  (Appendix 16) The multilayer structure film according to any one of appendices 9 to 15, wherein the ferromagnetic film is superposed on a surface of the second thin film.

  (Supplementary note 17) In the perpendicular magnetic storage medium according to any one of supplementary notes 9 to 16, the stacked body and the ferromagnetic film are arranged for each recording track separated by a nonmagnetic material, and are arranged in individual columns. A perpendicular magnetic storage medium characterized in that a plurality of magnetic pillars that are individually separated by a nonmagnetic material are formed.

  (Supplementary note 18) In the perpendicular magnetic storage medium according to supplementary note 17, the nonmagnetic material is formed of a nonmagnetic material buried in a space defined in the stacked body and the ferromagnetic film. Perpendicular magnetic storage medium.

  (Supplementary note 19) The perpendicular magnetic storage medium according to supplementary note 17, wherein the non-magnetic material is an altered region formed in the stacked body and the ferromagnetic film based on ion implantation. .

  (Supplementary Note 20) A storage medium and a head slider that faces the surface of the storage medium. The storage medium includes a substrate, a soft magnetic backing layer laminated on the surface of the substrate, and a backing layer. A nonmagnetic intermediate layer laminated on the surface, a first thin film formed from nonmagnetic noble metal atoms, and a second thin film formed from magnetic atoms or a magnetic alloy are repeatedly stacked on the nonmagnetic intermediate layer. A storage device comprising: a laminated body to be combined; and a ferromagnetic film which is superimposed on a surface of the laminated body and has a saturation magnetization larger than a saturation magnetization of the laminated body.

  DESCRIPTION OF SYMBOLS 11 Hard disk drive device as storage device, 14 Magnetic disk as perpendicular magnetic storage medium, 26 Magnetic pillar or magnetic dot, 27 Non-magnetic material, 28 Recording track, 32 Backing layer, 33 Multi-layered film, 37 Non-magnetic intermediate layer ( Tantalum adhesion layer), 38 nonmagnetic intermediate layer (palladium underlayer), 41 laminate, 42 ferromagnetic film, 43a first thin film (palladium layer), 43b second thin film (cobalt layer).

Claims (10)

  A laminated body in which a first thin film formed from nonmagnetic noble metal atoms and a second thin film formed from a magnetic atom or a magnetic alloy are repeatedly laminated, and a saturation magnetization of the laminated body, overlaid on the surface of the laminated body And a ferromagnetic film having a larger saturation magnetization.   2. The multilayer structure according to claim 1, wherein a uniaxial anisotropic magnetic field of the laminate and the ferromagnetic film is set larger than a uniaxial anisotropic magnetic field unique to the ferromagnetic film. film.   3. The multilayer structure film according to claim 1, wherein the magnetic atom is cobalt.   4. The multilayer structure film according to claim 1, wherein the nonmagnetic noble metal atom is palladium. 5.   5. The multilayer structure film according to claim 4, wherein the ferromagnetic film is formed of an alloy containing cobalt atoms and platinum atoms.   6. The multilayer structure film according to claim 5, wherein the alloy further contains chromium atoms.   7. The multilayer structure film according to claim 6, wherein a film thickness of the ferromagnetic film is set to 7.0 nm or less.   The multilayer structure film according to claim 1, wherein the ferromagnetic film is overlaid on a surface of the second thin film.   A substrate, a soft magnetic backing layer laminated on the surface of the substrate, a nonmagnetic intermediate layer laminated on the surface of the backing layer, and a nonmagnetic noble metal atom superimposed on the nonmagnetic intermediate layer. A laminated body in which a first thin film and a second thin film formed from a magnetic atom or a magnetic alloy are repeatedly laminated, and a saturation magnetization that is superimposed on a surface of the laminated body and that is larger than a saturation magnetization of the laminated body A perpendicular magnetic storage medium comprising a ferromagnetic film.   A storage medium; and a head slider that faces the surface of the storage medium, the storage medium being stacked on the surface of the substrate, a soft magnetic backing layer that is stacked on the surface of the substrate, and the surface of the backing layer. A non-magnetic intermediate layer, a first thin film formed on the non-magnetic intermediate layer and formed from non-magnetic noble metal atoms, and a laminate in which the second thin film formed from a magnetic atom or a magnetic alloy is repeatedly stacked. And a ferromagnetic film superposed on the surface of the stacked body and having a saturation magnetization larger than the saturation magnetization of the stacked body.

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