WO2007114400A1 - 垂直磁気記録媒体の製造方法 - Google Patents
垂直磁気記録媒体の製造方法 Download PDFInfo
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- WO2007114400A1 WO2007114400A1 PCT/JP2007/057316 JP2007057316W WO2007114400A1 WO 2007114400 A1 WO2007114400 A1 WO 2007114400A1 JP 2007057316 W JP2007057316 W JP 2007057316W WO 2007114400 A1 WO2007114400 A1 WO 2007114400A1
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- Prior art keywords
- layer
- magnetic recording
- magnetic
- forming
- recording medium
- Prior art date
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- 230000005291 magnetic effect Effects 0.000 title claims abstract description 198
- 238000000034 method Methods 0.000 title claims abstract description 30
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 23
- 238000010438 heat treatment Methods 0.000 claims abstract description 49
- 239000000758 substrate Substances 0.000 claims abstract description 21
- 230000006911 nucleation Effects 0.000 claims abstract description 15
- 238000010899 nucleation Methods 0.000 claims abstract description 15
- 239000010410 layer Substances 0.000 claims description 208
- 230000008878 coupling Effects 0.000 claims description 15
- 238000010168 coupling process Methods 0.000 claims description 15
- 238000005859 coupling reaction Methods 0.000 claims description 15
- 239000000126 substance Substances 0.000 claims description 10
- 239000011521 glass Substances 0.000 claims description 9
- 239000000696 magnetic material Substances 0.000 claims description 8
- 229910045601 alloy Inorganic materials 0.000 claims description 6
- 239000000956 alloy Substances 0.000 claims description 6
- 229910052697 platinum Inorganic materials 0.000 claims description 6
- 239000002356 single layer Substances 0.000 claims description 6
- 229910019222 CoCrPt Inorganic materials 0.000 claims description 5
- 229910052763 palladium Inorganic materials 0.000 claims description 4
- 229910002546 FeCo Inorganic materials 0.000 claims description 2
- 230000005294 ferromagnetic effect Effects 0.000 claims 1
- 230000015572 biosynthetic process Effects 0.000 description 15
- 239000010408 film Substances 0.000 description 13
- 238000010586 diagram Methods 0.000 description 11
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Substances [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 10
- 230000008569 process Effects 0.000 description 10
- 239000011241 protective layer Substances 0.000 description 10
- 230000001050 lubricating effect Effects 0.000 description 9
- 239000013078 crystal Substances 0.000 description 8
- 239000011651 chromium Substances 0.000 description 7
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 5
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 5
- 229910052804 chromium Inorganic materials 0.000 description 5
- 229910052814 silicon oxide Inorganic materials 0.000 description 5
- 239000000203 mixture Substances 0.000 description 4
- 239000005354 aluminosilicate glass Substances 0.000 description 3
- 238000005229 chemical vapour deposition Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000013067 intermediate product Substances 0.000 description 3
- 238000010030 laminating Methods 0.000 description 3
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Chemical compound [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 description 3
- 125000006850 spacer group Chemical group 0.000 description 3
- 238000004544 sputter deposition Methods 0.000 description 3
- 230000003746 surface roughness Effects 0.000 description 3
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium(II) oxide Chemical compound [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 230000005374 Kerr effect Effects 0.000 description 2
- 229910001069 Ti alloy Inorganic materials 0.000 description 2
- 230000009471 action Effects 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 239000005345 chemically strengthened glass Substances 0.000 description 2
- VNNRSPGTAMTISX-UHFFFAOYSA-N chromium nickel Chemical compound [Cr].[Ni] VNNRSPGTAMTISX-UHFFFAOYSA-N 0.000 description 2
- 230000001419 dependent effect Effects 0.000 description 2
- 238000003618 dip coating Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000001747 exhibiting effect Effects 0.000 description 2
- 230000003993 interaction Effects 0.000 description 2
- 238000001755 magnetron sputter deposition Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000010702 perfluoropolyether Substances 0.000 description 2
- 238000005498 polishing Methods 0.000 description 2
- 239000010409 thin film Substances 0.000 description 2
- 229910052845 zircon Inorganic materials 0.000 description 2
- GFQYVLUOOAAOGM-UHFFFAOYSA-N zirconium(iv) silicate Chemical compound [Zr+4].[O-][Si]([O-])([O-])[O-] GFQYVLUOOAAOGM-UHFFFAOYSA-N 0.000 description 2
- 229910018487 Ni—Cr Inorganic materials 0.000 description 1
- KJTLSVCANCCWHF-UHFFFAOYSA-N Ruthenium Chemical compound [Ru] KJTLSVCANCCWHF-UHFFFAOYSA-N 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 description 1
- ZGWQKLYPIPNASE-UHFFFAOYSA-N [Co].[Zr].[Ta] Chemical compound [Co].[Zr].[Ta] ZGWQKLYPIPNASE-UHFFFAOYSA-N 0.000 description 1
- LPOUEVYXAMBSRF-UHFFFAOYSA-N [Zr].[Ta].[Co].[Fe] Chemical compound [Zr].[Ta].[Co].[Fe] LPOUEVYXAMBSRF-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 239000012790 adhesive layer Substances 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- 230000005316 antiferromagnetic exchange Effects 0.000 description 1
- 238000003426 chemical strengthening reaction Methods 0.000 description 1
- 229910000423 chromium oxide Inorganic materials 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 230000010365 information processing Effects 0.000 description 1
- 238000005461 lubrication Methods 0.000 description 1
- 230000005381 magnetic domain Effects 0.000 description 1
- 239000006249 magnetic particle Substances 0.000 description 1
- 230000005415 magnetization Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 229910001120 nichrome Inorganic materials 0.000 description 1
- MOWMLACGTDMJRV-UHFFFAOYSA-N nickel tungsten Chemical compound [Ni].[W] MOWMLACGTDMJRV-UHFFFAOYSA-N 0.000 description 1
- JMOHEPRYPIIZQU-UHFFFAOYSA-N oxygen(2-);tantalum(2+) Chemical compound [O-2].[Ta+2] JMOHEPRYPIIZQU-UHFFFAOYSA-N 0.000 description 1
- BPUBBGLMJRNUCC-UHFFFAOYSA-N oxygen(2-);tantalum(5+) Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[Ta+5].[Ta+5] BPUBBGLMJRNUCC-UHFFFAOYSA-N 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 229910052707 ruthenium Inorganic materials 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000005361 soda-lime glass Substances 0.000 description 1
- 229910001936 tantalum oxide Inorganic materials 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/62—Record carriers characterised by the selection of the material
- G11B5/64—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent
- G11B5/66—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent the record carriers consisting of several layers
- G11B5/676—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent the record carriers consisting of several layers having magnetic layers separated by a nonmagnetic layer, e.g. antiferromagnetic layer, Cu layer or coupling layer
- G11B5/678—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent the record carriers consisting of several layers having magnetic layers separated by a nonmagnetic layer, e.g. antiferromagnetic layer, Cu layer or coupling layer having three or more magnetic layers
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/62—Record carriers characterised by the selection of the material
- G11B5/64—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent
- G11B5/66—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent the record carriers consisting of several layers
- G11B5/667—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent the record carriers consisting of several layers including a soft magnetic layer
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/84—Processes or apparatus specially adapted for manufacturing record carriers
Definitions
- the present invention relates to a method for manufacturing a perpendicular magnetic recording medium mounted on a perpendicular magnetic recording type HDD (node disk drive) or the like.
- a perpendicular magnetic recording type magnetic disk has recently been proposed.
- the easy axis of magnetization of the magnetic recording layer is adjusted to be oriented in the direction perpendicular to the substrate surface.
- the perpendicular magnetic recording method can suppress the thermal fluctuation phenomenon as compared to the in-plane recording method, and is suitable for increasing the recording density.
- Patent Document 1 JP-A-2005-285275 (Patent Document 1), an adhesion layer, a soft magnetic layer, a seed layer, an underlayer, a perpendicular magnetic recording layer, a medium protective layer, and a lubricating layer are formed in this order on a substrate.
- a technology relating to the perpendicular magnetic recording medium is disclosed.
- Patent Document 2 US Pat. No. 6,468,670 (Patent Document 2) has a structure in which an artificial lattice film continuous layer (exchange coupling layer) exchange-coupled to a particulate recording layer is attached.
- a perpendicular magnetic recording medium is disclosed! Speak.
- Patent Document 1 Japanese Patent Laid-Open No. 2005-285275
- Patent Document 2 US Pat. No. 6,468,670
- a perpendicular magnetic recording medium is provided with a soft magnetic layer below the magnetic recording layer, and returns from the recording head to the recording head via the soft magnetic layer.
- a method of applying a high recording magnetic field to the magnetic recording layer by forming a closed magnetic path is employed. This enables a strong magnetic field to be recorded on the recording track, and at the same time, the leakage magnetic field to adjacent tracks also increases. Therefore, WATE (Wide Area Track Erasure), that is, the track to be written is the center. The problem is that the recorded information disappears for several seconds per zm. This problem is particularly evident in formats where adjacent tracks are close (ie, high recording density).
- the present invention solves such problems, and a perpendicular magnetic layer comprising a soft magnetic layer, a magnetic recording layer having a dull-yura structure on a substrate, and a continuous layer having high perpendicular magnetic anisotropy.
- An object of the present invention is to provide a method of manufacturing a perpendicular magnetic recording medium that can easily increase the reverse domain nucleation magnetic field Hn of the magnetic recording layer.
- a method of manufacturing a perpendicular magnetic recording medium includes a soft magnetic layer forming step of forming a soft magnetic layer on a substrate, and a dollar as an upper layer of the soft magnetic layer.
- the substrate is preferably made of glass having excellent heat resistance.
- amorphous glass and crystallized glass can be used, and examples thereof include aluminosilicate glass, aluminoporosilicate glass, soda lime glass, and the like. Among these, aluminosilicate glass is preferable.
- the soft magnetic layer is amorphous, it is preferable that the substrate is made of amorphous glass.
- Use of chemically strengthened glass is preferable because of its high rigidity.
- the surface roughness of the main surface of the substrate is preferably 6 nm or less in terms of Rmax and 0.6 nm or less in terms of Ra.
- the gap between the perpendicular magnetic recording layer and the soft magnetic layer can be made constant, so that a suitable magnetic circuit can be formed between the magnetic head, the perpendicular magnetic recording layer, and the soft magnetic layer. it can.
- Each layer on the substrate is preferably formed by sputtering.
- the DC magnetron sputtering method makes it possible to form a uniform film, but from the viewpoint of mass production, it is also preferable to use an in-line film forming method.
- the soft magnetic layer is not particularly limited as long as it is formed of a magnetic material exhibiting soft magnetic properties.
- Fe-based soft magnetic materials, CoTaZr-based alloys, CoNbZr-based alloys and other Co-based soft magnetic materials, and FeCo-based alloy soft magnetic materials can be used.
- the soft magnetic layer preferably has a magnetic property of 0.01 to 80 Oersted, preferably 0.01 to 50 Oersted, in coercive force (He).
- the saturation magnetic flux density (Bs) preferably has a magnetic property of 500 emuZ cc to 1920 emuZcc.
- the thickness of the soft magnetic layer is preferably 5 nm to 1000 nm, and preferably 20 nm to 150 nm. If it is less than 5 nm, it may be difficult to form a suitable magnetic circuit between the magnetic head, the perpendicular magnetic recording layer, and the soft magnetic layer, and if it exceeds lOOOnm, the surface roughness may increase. Also lOOOnm If it exceeds 1, sputtering film formation may be difficult.
- the magnetic recording layer is preferably formed of CoCrPt containing a non-magnetic substance.
- a non-magnetic substance is a substance that can form a grain boundary around magnetic grains so that exchange interaction between magnetic grains (magnetic grains) is suppressed or blocked. Any non-magnetic substance that does not dissolve in solution may be used. Examples include silicon oxide (SiOx), chromium (Cr), acid chromium (CrO), titanium oxide (TiO), zircon oxide (ZrO), and tantalum oxide (TaO).
- SiO content is 3mol%
- the thickness of the magnetic recording layer is preferably 3nm or more, preferably 7 ⁇ ! ⁇ 15nm.
- the continuous layer is an exchange energy control layer formed by alternately laminating CoB and Pd or Pt, and a coupling control layer made of Pd or Pt and coupling the exchange energy control layer to the magnetic recording layer It is preferable to form by laminating.
- the exchange energy control layer is intended to improve the reverse domain nucleation magnetic field Hn. If the Hn can be improved, the exchange energy control layer need not be a multilayer film. Further, since the magnetic effect does not change, the exchange energy control layer can be disposed above or below the magnetic recording layer. When the exchange energy control layer is formed above the magnetic recording layer, the magnetic recording layer, the coupling control layer, and the exchange energy control layer are stacked in this order from below, and the exchange energy control layer is formed below the magnetic recording layer. If this is the case, the exchange energy primary control layer, the coupling control layer, and the magnetic recording layer should be stacked in this order in the downward direction,
- the heating step is preferably performed by heating a medium obtained by forming a continuous layer using a thermostatic chamber (heating device). Such heating of the medium may be performed in a vacuum or in the air as long as the medium surface is not contaminated.
- the heating temperature is preferably about 150 ° C to 240 ° C. Especially at about 200 ° C, it is possible to balance the ease of temperature control and ensuring a certain quality.
- FIG. 1 is a diagram illustrating a configuration of a perpendicular magnetic recording disk according to an example.
- FIG. 2 is a diagram for explaining a method of manufacturing the perpendicular magnetic recording disk of FIG.
- FIG. 3 is a diagram showing changes in magnetic properties due to heating in the heating step of FIG. 2.
- FIG. 4 is a diagram showing the relationship between heating temperature and reverse domain nucleation magnetic field.
- FIG. 5 is a diagram for explaining the configuration of a perpendicular magnetic recording disk (perpendicular magnetic recording medium) according to a second embodiment.
- FIG. 6 is a diagram showing changes in magnetostatic characteristics due to heating in the heating process.
- FIG. 1 is a diagram for explaining the configuration of a perpendicular magnetic recording disk (perpendicular magnetic recording medium) according to the first embodiment
- FIG. 2 is a flowchart for explaining a method of manufacturing the perpendicular magnetic recording disk
- FIG. 4 is a diagram showing the change in magnetic characteristics
- FIG. 4 is a diagram showing the relationship between the heating temperature and the reverse domain nucleation magnetic field Hn.
- the perpendicular magnetic recording disk shown in FIG. 1 includes a disk substrate 1, an adhesion layer 2, a soft magnetic layer 3, an orientation control layer 4, an underlayer 5, a single layer (magnetic recording layer) 6, a continuous layer 7, A medium protective layer 8 and a lubricating layer 9 are provided.
- the continuous layer 7 includes a coupling control layer 10 and an exchange energy control layer 11.
- amorphous aluminosilicate glass was formed into a disk shape by direct pressing, and the diameter was 65 mm (2.5 inches).
- a glass disk was created.
- the glass disk was subjected to polishing U, polishing, and chemical strengthening in order to obtain a smooth non-magnetic disk substrate 1 such as a chemically strengthened glass disk cover (step S1: described as “S1” in FIG. 2; the following).
- a smooth non-magnetic disk substrate 1 such as a chemically strengthened glass disk cover
- Step S2 to Step S8 Film formation was sequentially performed from the adhesion layer 2 to the continuous layer 7 on the obtained disk substrate 1 by a DC magnetron sputtering method in an Ar atmosphere using a vacuum-deposited film formation apparatus.
- the intermediate product (medium) obtained in step S8 was heated by a constant temperature layer (step S9), and the medium protective layer 8 was formed by the CVD method (step S10).
- the lubricating layer 9 was formed by dip coating (step Sl l).
- the adhesion layer 2 was formed using a Ti alloy target so as to become a lOnm Ti alloy layer.
- a Ti alloy target so as to become a lOnm Ti alloy layer.
- the adhesion between the disk substrate 1 and the soft magnetic layer 3 can be improved, so that the soft magnetic layer 3 can be prevented from peeling off.
- the material of the adhesion layer 2 for example, a Ti-containing material can be used. From a practical point of view, the thickness of the adhesive layer is Inn! It is preferable to be set to ⁇ 50 nm.
- the soft magnetic layer 3 was formed using a CoTaZr target so as to be an amorphous CoTaZr layer of 50 nm.
- the orientation control layer 4 was formed using a Ta target so that an amorphous Ta force layer was formed to a thickness of 3 nm.
- a Ru layer having a thickness of 20 nm was formed as the underlayer 5. Note that the underlayer 5 may be two layers having Ru force.
- the crystal orientation can be improved by making the Ar gas pressure higher than when forming the lower layer side Ru.
- the Dara-Yura single layer 6 uses a hard magnetic target made of CoCrPt containing SiO as an example of a non-magnetic substance, and uses a lOnm hep crystal.
- a non-magnetic substance is a substance that can form a peripheral boundary of magnetic grains so that exchange interaction between magnetic grains (magnetic grains) is suppressed or blocked, and cobalt (Co) Any non-magnetic substance that does not dissolve in solution can be used.
- the coupling control layer 10 was formed of a Pd layer.
- the coupling control layer 10 can be formed of a Pt layer in addition to the Pd layer. Coupling
- the thickness of the control layer 10 is preferably 2 nm or less, and more preferably 0.5 to 1.5 nm.
- the exchange energy control layer 11 is made of an alternately laminated film of CoB and Pd and formed at a low Ar gas pressure.
- the film thickness of the exchange energy control layer 11 is preferably 1 to 8 nm, and more preferably 3 to 6 nm.
- the exchange energy control layer 11 may be formed by using Pt instead of Pd and alternately laminating CoB and Pt.
- the intermediate product obtained after the formation of the exchange energy control layer 11 was heated at a predetermined temperature in a constant temperature bath for a predetermined time.
- the heating temperature at this time is higher than 100 ° C. and lower than 250 ° C. and lower than that in the case of general annealing treatment, and preferably about 150 ° C. to 240 ° C.
- the medium protective layer 8 was formed by forming a carbon film by the CVD method while maintaining the vacuum.
- the medium protective layer 8 is a protective layer for protecting the perpendicular magnetic recording layer by the impact force of the magnetic head.
- carbon film formed by CVD method has higher film hardness than that formed by sputtering method, so that the perpendicular magnetic recording layer can be protected more effectively against the impact from the magnetic head. .
- the lubricating layer 9 was formed by dip coating using PFPE (perfluoropolyether).
- the thickness of the lubricating layer 9 is about lnm.
- FIG. 3 shows the measurement results of the Kerr effect measuring device for the perpendicular magnetic recording disk manufactured by the above process.
- FIG. 3 exemplifies the magnetic characteristics when the heating process is performed and the magnetic characteristics when the same process is not performed (heating temperature in the heating process is 200 ° C.).
- the heat treatment makes the hysteresis loop steep and the absolute value of the reverse domain nucleation magnetic field Hn increases.
- Fig. 4 is a graph showing the relationship between the heating temperature and the reverse domain nucleation magnetic field Hn when the temperature is changed from 50 ° C to 250 ° C in a thermostatic chamber.
- the value of Hn is dependent on the heating temperature, and it can be seen that the heating temperature is significantly improved when the heating temperature is about 150 ° C to 240 ° C, especially around 230 ° C.
- the value of Hn rapidly decreases when the heating temperature exceeds 230 ° C, so it is necessary to balance the ease of temperature control with ensuring certain quality!
- the heating temperature should be 200 ° C. It is also very effective to manufacture perpendicular magnetic recording media with the following settings.
- the heating step was performed immediately after the exchange energy control layer 11 was formed.
- the present invention is not limited to the above steps, and after the exchange energy control layer 11 is formed, the same effect can be obtained by performing heat treatment after forming the medium protective layer 8, the lubricating layer 9, and other films. be able to.
- FIG. 5 is a diagram for explaining the configuration of a perpendicular magnetic recording disk (perpendicular magnetic recording medium) according to the second embodiment
- FIG. 6 is a diagram showing changes in magnetostatic characteristics due to heating in the heating process.
- the same parts as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted.
- the perpendicular magnetic recording disk shown in FIG. 5 includes a disk substrate 1, a soft magnetic layer 23, an orientation control layer 4, an underlayer 25, an onset layer 27, a dura-yura layer 6 (magnetic recording layer), and an auxiliary recording layer 29.
- Media protective layer 8 and lubricating layer 9 are provided.
- the soft magnetic layer 23 has an AFC (Antiferro-magnetic exchange coupling) by interposing a nonmagnetic spacer layer 23b between the first soft magnetic layer 23a and the second soft magnetic layer 23c. (Exchange coupling).
- AFC Antiferro-magnetic exchange coupling
- the magnetic directions of the first soft magnetic layer and the second soft magnetic layer can be aligned antiparallel to each other with high accuracy, and noise generated from the soft magnetic layer 23 can be reduced.
- the composition of the first soft magnetic layer 23a and the second soft magnetic layer 23c can be CoTaZr (cobalt tantalum-zirconium) or CoFeTaZr (cobalt iron-tantalum-zirconium).
- the composition of the spacer layer 23b was Ru (ruthenium).
- the orientation control layer 4 has an action of protecting the soft magnetic layer 23 and an action of promoting alignment of crystal grains of the underlayer 25.
- the orientation control layer 4 can be a layer of Pt (platinum), Ni W (nickel tungsten) or NiCr (nickel chromium) having a fee structure.
- the underlayer 25 has a two-layer structure made of Ru.
- the crystal orientation and the single-layer layer 6 are increased by increasing the Ar gas pressure more than when forming the first underlayer 25a on the lower layer side.
- the separation of magnetic particles can be improved at the same time.
- the onset layer 27 is a non-magnetic dura-yura layer. By forming a non-magnetic layer 6 on the hep crystal structure of the underlayer 25 and growing a layer 6 on this layer, the magnetic layer 6 is separated from the initial stage (rise) force. Has the effect of causing
- the composition of the onset layer 27 was non-magnetic CoCrRu—SiO 2 (SiO: silicon oxide).
- Dara-Yura layer 6 is a CoCrPt containing a non-magnetic substance, titanium oxide (TiO).
- a hep crystal structure was formed using a hard magnetic target composed of bartochrome (platinum).
- the auxiliary recording layer 29 (continuous layer) forms a thin film exhibiting high perpendicular magnetic anisotropy on the dura-yura layer 6 and constitutes an exchange energy control layer.
- the auxiliary recording layer 29 can be provided with high heat fluctuation resistance.
- the composition of the auxiliary recording layer 29 was CoCrPtB.
- the intermediate product obtained after the formation of the auxiliary recording layer 29 was heated at a predetermined temperature for a predetermined time in a thermostatic chamber.
- the heating temperature at this time is higher than 100 ° C and lower than 250 ° C, and lower than that in the case of a general alarm treatment, preferably about 150 ° C to 240 ° C.
- the medium protective layer 8 and the lubricating layer 9 were formed in the same manner as in the first example. Through the above manufacturing process, a perpendicular magnetic recording medium was obtained.
- Fig. 6 and Table 1 The magnetostatic characteristics of the obtained perpendicular magnetic recording disk were evaluated using a Polar Kerr effect measuring apparatus. The results are shown in Fig. 6 and Table 1.
- heat treatment 1 was subjected to a heating process at 210 ° C
- heat treatment 2 was subjected to a heating process at 240 ° C
- non-heat treatment was subjected to a heating process as a comparative example. This is the case.
- Oe is Oersted (representing the strength of the magnetic field).
- the hysteresis loop is improved by heat treatment.
- the slope is steep, and the absolute value of the reverse domain nucleation magnetic field Hn is increasing.
- the value of Hn is dependent on the heating temperature. It can be seen that the heating temperature increases slightly from non-heat treatment to heat treatment 1 and further increases by heat treatment 2. Karu.
- the reverse domain nucleation magnetic field Hn can be easily increased without significantly changing the existing manufacturing process (without impairing mass productivity). The characteristics can be improved.
- the present invention can be used as a method for manufacturing a perpendicular magnetic recording medium mounted on a perpendicular magnetic recording type HDD or the like.
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- Manufacturing Of Magnetic Record Carriers (AREA)
- Magnetic Record Carriers (AREA)
- Thin Magnetic Films (AREA)
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
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JP2008508689A JPWO2007114400A1 (ja) | 2006-03-31 | 2007-03-31 | 垂直磁気記録媒体の製造方法 |
US12/295,550 US20090191331A1 (en) | 2006-03-31 | 2007-03-31 | Perpendicular magnetic recording medium manufacturing method |
Applications Claiming Priority (2)
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JP2006-100321 | 2006-03-31 | ||
JP2006100321 | 2006-03-31 |
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WO2007114400A1 true WO2007114400A1 (ja) | 2007-10-11 |
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PCT/JP2007/057316 WO2007114400A1 (ja) | 2006-03-31 | 2007-03-31 | 垂直磁気記録媒体の製造方法 |
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US (1) | US20090191331A1 (ja) |
JP (2) | JPWO2007114400A1 (ja) |
WO (1) | WO2007114400A1 (ja) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2009289338A (ja) * | 2008-05-29 | 2009-12-10 | Fuji Electric Device Technology Co Ltd | 磁気記録媒体及びその製造方法 |
JPWO2010038754A1 (ja) * | 2008-09-30 | 2012-03-01 | ダブリュディ・メディア・シンガポール・プライベートリミテッド | 磁気記録媒体の製造方法および磁気記録媒体 |
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