JP2010231836A - Method for manufacturing magnetic storage medium, and information storage device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the flatness of a surface, in a method for manufacturing a magnetic recording medium with which a recording layer of a rugged pattern is made flat. <P>SOLUTION: In order to flat the rugged pattern forming the recording layer 32-1, polishing is conducted by disposing a second filler 38 with a low polishing rate on a first filler 36 with a high polishing rate. Only necessary sections are made to have a low polishing rate, without prolonging the polishing time period. Consequently, high flatness for the surface is obtained, without impairing manufacturing efficiency, manufacturing margin, or the like. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a magnetic storage medium having an uneven pattern and an information storage device.

  In recent years, magnetic recording / reproducing apparatuses such as hard disk drives (HDD) have been rapidly reduced in size and capacity. The magnetic recording medium of the magnetic recording / reproducing apparatus has a structure in which a magnetic thin film is laminated on a glass or aluminum alloy substrate by sputtering or the like. The recording magnetic material has been devised in various ways to make the magnetic particles smaller, and the magnetic particle unit has been reduced to about 8 nm.

  The miniaturization of the magnetic particles mainly contributes to the reduction in noise of the recording medium. However, this miniaturization is screaming for its limits, and so-called discrete track media and patterned media have been proposed as a breakthrough.

  These media are characterized by patterning a film of a recording magnetic material. In the case of a discrete track medium, the bit patterned medium is patterned in both the circumferential direction and the radial direction in the radial direction, and the recording film has irregularities.

  In addition, since it is necessary to lift the head and read and write signals, after forming a concavo-convex pattern, a nonmagnetic material or the like is formed to fill the recess, and the surface is flattened by polishing or the like to withstand the head levitation. (For example, refer to Patent Documents 1 and 2).

  13 and 14 are explanatory views of a conventional method for manufacturing a magnetic storage medium having unevenness. FIG. 13 is an explanatory view of a process of filling the uneven pattern with a filler, and FIG. 14 is a cross-sectional view of the surface shape after polishing the filled medium.

  As shown in FIG. 13, a soft magnetic underlayer, a crystal control underlayer or the like is formed on the nonmagnetic substrate 100 by sputtering or the like as necessary, and then a recording layer 102 made of a magnetic material is formed. Accordingly, a polishing stopper layer 104 is formed. Thereafter, a resist is formed in order to pattern the unevenness, and the resist is patterned by nanoimprint or EB drawing. Using the patterned resist as a mask, the magnetic film 102 is etched to form a concavo-convex pattern on the magnetic film 102.

  In FIG. 13, an uneven pattern composed of a magnetic layer 102 and a polishing stopper layer 104 is formed on a nonmagnetic substrate 100. A nonmagnetic filler is filled in the recesses of the uneven pattern to form a nonmagnetic filler layer 106.

  Next, as shown in FIG. 14, the surface of the nonmagnetic filling layer 106 is polished and planarized by a polishing pad (not shown). This flatness affects the flying height of the magnetic head, and the degree of flatness is important.

Japanese Patent No. 4076889 (Japanese Patent Laid-Open No. 2004-295989) JP 2007-164845 A

  In the conventional method, the filling material is formed to fill the recesses, and then, in the process of flattening the surface by polishing, particularly when a relatively soft polishing pad is used, the patterning is performed with a wide width. In the recess, the filling portion is recessed due to overpolishing, and a step is generated.

  Usually, a material having a higher polishing rate than the recording layer 102 is filled as the filler 106 and polished so that the recording layer convex portion 102 is not polished. Therefore, when the polishing process is performed, even if the recording layer convex portion 102 is not polished, the filler 106 in the concave portion is gradually polished, and the soft polishing pad becomes uneven on the surface of the medium. The deformation is considered to be a factor.

  In particular, in a region where a magnetic film for forming a servo pattern is provided, a wide concave portion exists. As this step is polished longer than the appropriate polishing time, the convex portion 102 is hardly scraped off, whereas only the concave portion 106 is scraped off, so that the step becomes larger. For example, even if the level difference is 10 and several nanometers, the flying height of the head corresponding to the high recording density is 10 nanometers or less, and thus the flying height is greatly affected. In addition, the manufacturing process margin is small.

  An object of the present invention is to provide a method of manufacturing a magnetic storage medium and an information storage device for reducing the level difference on the surface of the medium that may occur after polishing.

  In order to achieve this object, a method of manufacturing a magnetic storage medium includes a step of forming a recording layer on a substrate, a predetermined uneven pattern on the recording layer, and a polishing stopper layer on the convex part of the uneven pattern. Forming a first filling layer having a polishing rate higher than that of the polishing stopper layer on the recesses of the uneven pattern and the polishing stopper layer, and forming the first filling layer on the first filling layer. Forming a second filling layer having a polishing rate lower than that of the first filling layer, and polishing the second filling layer and the first filling layer until the polishing stopper layer is exposed; Have

  The information storage device also includes a magnetic storage medium manufactured by the method of manufacturing the magnetic storage medium, a head that records and / or reproduces information on the magnetic storage medium, and a recording and reproduction operation of the floating head. And a control circuit for controlling.

  Since the second filler having a low polishing rate is provided on the first filler having a high polishing rate in order to flatten the uneven pattern forming the recording layer, a necessary portion without increasing the polishing time. Only a low polishing rate can be achieved. Thereby, high flatness of the surface can be obtained without impairing the production efficiency, the production margin, and the like.

1 is an external view of an embodiment of an information storage device of the present invention. It is explanatory drawing of the servo zone and data zone of the disk of FIG. It is explanatory drawing of the magnetic film formation process of 1st Embodiment of the manufacturing method of the magnetic-recording medium of this invention. It is explanatory drawing of the uneven | corrugated pattern formation process of 1st Embodiment of the manufacturing method of the magnetic-recording medium of this invention. It is explanatory drawing of the nonmagnetic filling layer formation process of 1st Embodiment of the manufacturing method of the magnetic-recording medium of this invention. It is explanatory drawing of the grinding | polishing process of 1st Embodiment of the manufacturing method of the magnetic-recording medium of this invention. It is explanatory drawing of the nonmagnetic filling layer formation process of 2nd Embodiment of the manufacturing method of the magnetic-recording medium of this invention. It is explanatory drawing of the grinding | polishing process of 2nd Embodiment of the manufacturing method of the magnetic-recording medium of this invention. It is a figure which shows the measurement result of polishing time and surface roughness Ra of the Example and comparative example of this invention. It is a figure which shows the measurement result of the grinding | polishing time and level | step difference of the Example and comparative example of this invention. It is a related figure of the gas pressure and polishing rate of the Example of this invention. FIG. 4 is a relationship diagram of oxygen partial pressure and polishing rate in an example of the present invention. It is explanatory drawing of the nonmagnetic filling layer formation process of the manufacturing method of the conventional magnetic recording medium. It is explanatory drawing of the grinding | polishing process of the manufacturing method of the conventional magnetic recording medium.

  Hereinafter, embodiments of the present invention will be described in the order of the information storage device, the first embodiment of the method of manufacturing the magnetic recording medium, the second embodiment of the magnetic recording medium, the example, and the other embodiments. Although described, the present invention is not limited to this embodiment.

(Information storage device)
FIG. 1 is an external view of an embodiment of an information storage device of the present invention, and FIG. 2 is an explanatory diagram of a servo zone and a data zone of the disk of FIG. FIG. 1 shows a hard disk drive as an example of the information storage device.

  As shown in FIG. 1, a disk enclosure (referred to as DE) 1 accommodates each component of a magnetic disk device. In the DE 1, a magnetic disk 3 that is a magnetic recording medium is provided on the rotation shaft of the spindle motor 4.

  The spindle motor 4 attached to the DE 1 rotates the magnetic disk 3. An actuator (VCM) 5 using a VCM (voice coil motor) rotates an arm (including a suspension) 52. A slider 53 including a magnetic head is provided at the tip of the arm suspension. Therefore, the actuator 5 moves the slider 53 including the magnetic head in the radial direction of the magnetic disk 3.

  The actuator 5 is composed of a voice coil motor (VCM) that rotates about a rotation axis. In FIG. 1, one magnetic disk 3 is mounted on the magnetic disk device, and two sliders 53 including a magnetic head are simultaneously driven by the same actuator 5 on each surface of the magnetic disk.

  A ramp mechanism 54 for retracting the slider 53 from the magnetic disk 3 and parking is provided outside the magnetic disk 3. A lift tab that engages with the ramp mechanism 54 is provided at the tip of the suspension.

  The slider 53 has a read element and a write element. The slider 53 is configured by laminating a read element including a magnetoresistive (MR) element on a slider body and laminating a write element including a write coil thereon. The lowermost part of the slider 53 forms an air bearing surface.

  As shown in FIG. 2, the magnetic disk 3 is composed of a data zone 211 and a servo zone 212. In FIG. 2, the black portion indicates a magnetic film.

  The data zone 211 is formed by separating the magnetic films constituting each bit and forming a row in the circumferential direction of the magnetic disk 3. On the other hand, in the servo zone 212, the servo pattern is formed of a magnetic film. Here, the servo pattern 212 includes a preamble 221, a servo mark 222, an address 223, and a minute position detection pattern (burst pattern) 224.

  Thus, in the bit pattern medium, the servo pattern 212 forms a relatively wide recess.

(First Embodiment of Manufacturing Method of Magnetic Recording Medium)
3 to 6 are process diagrams of the first embodiment of the method of manufacturing the magnetic recording medium according to the present invention. 3 is an explanatory view of the magnetic film forming step, FIG. 4 is an explanatory view of the uneven pattern forming step, FIG. 5 is an explanatory view of the nonmagnetic filling layer forming step, and FIG. 6 is an explanatory view of the polishing step.

  As shown in FIG. 3, a soft magnetic underlayer, a crystal control underlayer, and the like are formed on a nonmagnetic substrate 30 by sputtering or the like, if necessary, and then a recording layer 32 made of a magnetic material is formed. Further, a polishing stop layer 34 having a low polishing rate is formed after the magnetic recording layer 32 is formed so that the magnetic recording layer 32 is not damaged during polishing. Further, an etching protective layer and an etching mask layer are formed as necessary.

  As shown in FIG. 4, after that, a resist is formed in order to pattern the unevenness, and the resist is patterned by nanoimprint or EB (Electron Beam) drawing. Using the patterned resist as a mask, the magnetic film 32 is etched by IBE (Ion Beam Etching), RIE (Reactive Ion Etching), or the like, and an uneven pattern is formed on the magnetic film 32. If the resist or etching mask layer remains, the resist is removed. As a result, the magnetic layer 32 is converted into the separated magnetic layer 32-1 (including the polishing stop layer 34-1).

  As shown in FIG. 5, thereafter, the filler 36 and the second filler 38 having a polishing rate lower than that of the filler 36 are sequentially formed by sputtering or CVD (Chemical Vapor Deposition).

  Then, as shown in FIG. 6, the surface is flattened by mechanical polishing, chemical mechanical polishing (CMP), or the like.

  As shown in FIG. 6, since the polishing rate of the second filler 38 is low, the second filler 38 remaining in the original concave portion plays a role close to the polishing stop layer 34-1 and is recessed. Therefore, the occurrence of a step can be prevented.

  Furthermore, even if polishing is performed longer than an appropriate polishing time, the second filler 38 has a low polishing rate, so that the step is difficult to expand, and thus a manufacturing process with a large manufacturing process margin can be realized. Further, the formation thickness of the second filler 38 is preferably increased when it is desired to take a large margin in the manufacturing process, but the time for polishing the second filler 38 on the convex portion becomes longer. For the reason of shortening the process time, it is preferable to set the necessary minimum thickness.

  Next, the merits of filling and flattening according to the embodiment of the present invention will be supplemented. In the conventional method, the magnetic film convex portions are not polished, and only the upper layer portion of the excess filler is polished. Therefore, the magnetic film or the polishing stopper layer is filled with a material that is easily polished as a filler, and polished. . However, due to the ease of polishing, the wide concave portion is polished more than necessary, resulting in a step difference.

  In order to solve this problem, it is conceivable to use a material that is difficult to polish, that is, a low polishing rate, for the filler itself, so that it is difficult for the recess to be recessed with respect to polishing. It takes a long time to polish a low filler. When the length is increased, the manufacturing efficiency is lowered, and there is a concern that the length of the recessed portion will eventually deepen due to excessive polishing.

  On the other hand, in the embodiment of the present invention, the second filler 38 having a low polishing rate is provided on the first filler 36 having a high polishing rate, so that it is necessary without increasing the polishing time. Only the portion can have a low polishing rate. Thereby, high flatness of the surface can be obtained without impairing the production efficiency, the production margin, and the like.

  In addition, the second filler 38 having a low polishing rate is partially present on the convex portion. However, since the convex portion is subjected to a large polishing pressure during polishing, the second filler 38 present on the convex portion is present. The filler 38 can be removed by sufficiently short polishing, and the polishing time can be minimized.

  The polishing rate of the filler can be controlled by selecting materials having different hardnesses or materials having different chemical reactions with the abrasive grains. In the present embodiment, process efficiency can be improved by controlling the polishing rate by the following method.

  One is a method of forming a filler by sputtering. At this time, the polishing rate is controlled by the sputtering gas pressure. In general, it is known that when the gas pressure during sputtering is increased, the density of the film decreases. As a result of our research, it was found that the polishing rate was improved by decreasing the film density.

  In the case of controlling the polishing rate by gas pressure, the first filler 36 and the second filler 38 can be formed by changing only the gas pressure using the same sputtering target, thereby improving the process efficiency. Is possible.

  The other method is a method of polishing by chemical mechanical polishing (CMP) in which the filler is silicon oxide (SiO 2) and the abrasive grains during polishing are ceria oxide. At this time, the polishing rate is controlled by controlling the amount of oxygen in the silicon oxide. CMP of a silicon oxide film using ceria oxide grains is being used in a semiconductor process because it can be polished at a high rate and high quality, and is also a technique that can be expected for polishing a magnetic recording medium.

  This high polishing rate is thought to be due to the chemical reaction of ceria oxide and silicon oxide via oxygen. The inventors of the present invention performed polishing of silicon oxide with varying amounts of oxygen and confirmed the polishing rate. As a result, it was confirmed that the polishing rate could be controlled by the amount of oxygen of silicon oxide.

  Even when a target material of silicon oxide (SiO2) having a stoichiometric composition is used, a film formed by sputtering usually lacks oxygen and tends to be SiOx (x <2). In this state, when polishing with ceria oxide grains is performed, a high polishing rate cannot be obtained. However, by mixing oxygen with the process gas at the time of sputtering, oxygen is replenished and the polishing rate is improved.

  Therefore, the polishing rate can be controlled by changing the partial pressure of the oxygen gas. For example, the oxygen partial pressure of the first filler 36 and the second filler 38 can be changed in one chamber. However, it can be formed efficiently. Further, since silicon oxide is an insulator, RF sputtering is used for sputtering. As another method, silicon oxide in which the amount of oxygen is controlled can be formed by changing the oxygen partial pressure by DC sputtering of a Si target.

  Next, the laminated film thickness of the filler will be described. When the depth of the concave portion of the concave / convex pattern of the medium before forming the fillers 36 and 38 is “d” (see FIG. 6) and the surface step allowed for head flying is “s”, the first filling is performed. The relationship between the material 36 and the film thickness tF1, tF2 (see FIG. 5) of the second filler 38 is tF1 <d and | tF1 + tF2-d | It becomes easy to make it "s" or less.

  Actually, since it is difficult to manufacture everything as designed, the magnetic film convex portion or the polishing stop layer 34-1 formed on the magnetic film has a flatness when it is not substantially polished by the polishing process. For this purpose, tF1 <d and tF1 + tF2 ≧ d may be satisfied. The upper limit of tF2 is determined by the balance with the manufacturing margin.

(Second Embodiment of Manufacturing Method of Magnetic Recording Medium)
7 to 8 are process diagrams of the second embodiment of the magnetic recording medium manufacturing method of the present invention. FIG. 7 is an explanatory view of the nonmagnetic filling layer forming step, and FIG. 8 is an explanatory view of the polishing step.

  Also in the second embodiment shown in FIGS. 7 and 8, the magnetic layer forming step and the uneven pattern forming step are the same as those described with reference to FIGS. In the nonmagnetic filling layer forming step of FIG. 7, the filling material 36, the second filling material 38 having a lower polishing rate than the filling material 36, and the second filling material are formed by sputtering or CVD (Chemical Vapor Deposition). A third filling layer 40 having a polishing rate higher than 38 is sequentially formed.

  Then, as shown in FIG. 8, the surface is flattened by mechanical polishing, chemical mechanical polishing (CMP), or the like.

  In this embodiment, the third filler 40 is further formed in order to improve the planarization quality. That is, in order to increase the manufacturing efficiency, the film thickness of the second filler 38 having a low polishing rate is set to the minimum necessary, and the second filler 38 is obtained in order to obtain a filler film thickness necessary for flattening. The third filler 40 having a higher polishing rate is formed on the second filler 38 and then polished.

  Therefore, if the magnetic film convex portion or the polishing stop layer 34-1 formed on the magnetic film convex portion is not substantially polished by the polishing process, in order to obtain flatness, tF1 <d and tF1 + tF2 ≧ In the case of d, the upper limit of tF2 is determined by the balance with the manufacturing margin, and the film thickness can be adjusted with the third filler 40 having a high polishing rate.

  Even if the film thickness of the second filler 38 having a low polishing rate is minimized, it can be planarized, and thus the time required for manufacturing can be shortened. In addition, as in the first embodiment, the fillers 36, 38, and 40 are formed by a method of selecting a material having a different hardness, a material having a different chemical reaction with the abrasive grains, or a method of forming the filler by sputtering. When forming, polishing is performed by chemical mechanical polishing (CMP) in which the polishing rate is controlled by the sputtering gas pressure, or the filler is silicon oxide (SiO 2) and the polishing grains are ceria oxide. The method can be applied.

  As described above, it is possible to manufacture a patterned medium having high flatness while ensuring high manufacturing efficiency and a sufficient manufacturing margin.

[Example 1] (filling and polishing)
As shown in FIG. 3, on a glass substrate (disk substrate) 30, a CoFe-based soft magnetic underlayer that assists writing with a magnetic head (perpendicular recording head), Ta for cutting the crystal form of the soft magnetic underlayer. An amorphous underlayer, a Ru intermediate layer for controlling the crystal form of the magnetic layer, a Co alloy magnetic layer 32, and a Ta stopper layer 34 for stopping polishing were formed by DC sputtering.

  The stopper layer 34 may be formed after subsequent patterning. The material of the stopper layer 34 is not limited to Ta, but may be any material that is harder to polish than the filler 36 to be filled later. In general, Ta, TaN, SiN, Ti, TiN, or the like can be used.

  Furthermore, the resist for pattern formation was apply | coated and the shape of the glass mold which has a predetermined uneven | corrugated pattern was transcribe | transferred using nanoimprint. By using this resist pattern as a mask and ion milling, an uneven shape with a depth of about 25 nm was formed in the magnetic film 32. Finally, the resist residue was removed by oxygen ashing, and a medium having a concavo-convex shape before filling and planarization was produced (see FIG. 4).

  Next, the film was returned to the sputtering apparatus again, and a first filler 36 having a thickness of 20 nm was formed by RF sputtering using an SiO 2 target at an Ar gas pressure of 3 Pa (pascal). Next, an Ar gas pressure was set to 0.67 Pa, a 10 nm second filler 38 was formed, and an Ar gas pressure was returned to 3 Pa to form a 15 nm third filler 40 (see FIG. 7).

  In this embodiment, the polishing rate is controlled by the film density, but the fillers 36, 38, and 40 can be freely selected as long as the rate changes by polishing. For example, it is possible to simply use a combination of Ta, TaN, WN, TiN, etc. with high mechanical hardness and Cu, Al, etc. with low hardness. Further, when polishing with a ceria oxide slurry, a material in which the amount of oxygen of silicon oxide is changed may be used.

  Next, CMP was performed using a slurry liquid containing ceria oxide and a suede-like polishing pad. At this time, the slurry has diluted the stock solution 3 times with pure water.

  For comparison, when depositing the filler, a conventional configuration (FIG. 13) in which only the first filler was deposited to a thickness of 45 nm was prepared, and similarly, a CMP-polished medium was also produced.

  It is confirmed in advance that the standard polishing time in which the SiO2 layer on the pattern convex portion is exactly 15 minutes for the medium of this example and 10 minutes for the comparative medium, and 12 minutes to 18 in this example. In the comparative example, the polishing was performed for 8 minutes to 12 minutes and 80% to 120% of the standard polishing time.

  Furthermore, the uneven | corrugated level | step difference after grinding | polishing of each of these media and surface average roughness (Ra) were measured with the atomic force microscope (AFM).

  FIG. 9 shows measurement results in which the time normalized by the standard polishing time is plotted on the horizontal axis and the surface roughness Ra is plotted on the vertical axis. FIG. 10 similarly shows a measurement result in which a step difference obtained by measuring a 240 nm L / S (line and space having a cycle of 480 nm) is plotted. 9 and 10, the dotted line is the measurement result of the comparative medium, and the solid line is the measurement result of the example.

  Comparing both the comparative medium and the medium of the example, the comparative medium is larger in both surface roughness Ra and step even in the standard polishing time. Furthermore, when polishing is continued (the polishing time is lengthened), the comparative medium becomes extremely large in both surface roughness Ra and level difference. On the other hand, even if the medium of this example continues to be polished, the surface roughness Ra and the step increase are slight. As a result, it can be seen that the planarization can be performed with a margin.

[Example 2] (Polishing rate control 1)
After the Ta polishing stop layer 34 used in Example 1 was formed to a thickness of 30 nm on the glass substrate 30 by DC sputtering, silicon oxide was formed at 0.67 Pa, 3 Pa, and 6 Pa by RF sputtering using a SiO 2 target. Each 45 nm film was formed. These samples were polished by the same polishing method as in Example 1 except that the slurry stock solution was diluted 5 times, and the film formation rate was measured.

  FIG. 11 is a relationship diagram based on the above measurement, in which the gas pressure during sputtering of the SiO 2 target is plotted on the horizontal axis and the polishing rate is plotted on the vertical axis. It can be seen that if the gas pressure is changed, the polishing rate is variable in the range of 5 times or more.

[Example 3] (Polishing rate control 2)
A Ta polishing stop layer used in Example 1 was formed to a thickness of 30 nm on the glass substrate 30 by DC sputtering, and then SiO 2 was deposited to a thickness of 45 nm by RF sputtering using a SiO 2 target.

  At this time, a large number of samples were prepared with an oxygen partial pressure of 0 to 0.35 Pa by changing the total gas pressure during film formation to 3 Pa and changing the flow ratio of argon to oxygen. Each sample was polished by the same polishing method as in Example 1, and the film formation rate was measured.

  FIG. 12 is a graph showing the relationship between the oxygen partial pressure (Pa) and the polishing rate (nm / min) during the SiO 2 sputtering. From FIG. 12, it can be seen that if the oxygen partial pressure is changed, the polishing rate is variable in a range of up to about 5 times.

  In Example 3, the SiO 2 target was used. However, even with the Si target, the oxygen amount can be similarly controlled by generally increasing the oxygen supply amount.

(Other embodiments)
In the above-described embodiment, the polishing stop layer is formed before the magnetic film patterning step. However, the polishing stopper layer 34 may be formed after the magnetic film patterning. Although the magnetic recording medium has been described as a magnetic disk, it can also be applied to magnetic recording media of other shapes. Although the bit pattern medium has been described as an example, the present invention can also be applied to a discrete track medium in which magnetic tracks are separated by a nonmagnetic filler. Furthermore, although the description has been given with respect to a completely floating type head, it can also be applied to a near-contact type head that makes partial contact.

  As mentioned above, although this invention was demonstrated by embodiment, in the range of the meaning of this invention, this invention can be variously deformed, These are not excluded from the scope of the present invention.

  As described above, the present invention includes the following matters.

(Appendix 1)
In the method for manufacturing a magnetic storage medium, a step of forming a recording layer on a substrate, a step of forming a predetermined concavo-convex pattern on the recording layer, and a polishing stopper layer on a convex portion of the concavo-convex pattern, and the concavo-convex pattern Forming a first filling layer having a polishing rate higher than that of the polishing stopper layer on the recess and the polishing stopper layer, and polishing on the first filling layer as compared with the first filling layer. Forming a second filling layer having a low rate, and polishing the second filling layer and the first filling layer until the polishing stopper layer is exposed. A method of manufacturing a magnetic storage medium.

(Appendix 2)
A third filling layer having a polishing rate higher than that of the second filling layer is formed on the second filling layer between the step of forming the second filling layer and the polishing step. The method of manufacturing a magnetic storage medium according to appendix 1, further comprising a step.

(Appendix 3)
The first filling layer and the second filling layer are formed by a sputtering method, and the polishing of each of the first filling layer and the second filling layer is performed by a gas pressure of the sputtering method. The method of manufacturing a magnetic storage medium according to appendix 1, wherein a rate is set.

(Appendix 4)
The first filling layer, the second filling layer, and the third filling layer are formed by a sputtering method, and the first filling layer and the second filling layer are formed by a gas pressure of the sputtering method. The method of manufacturing a magnetic storage medium according to appendix 2, wherein the polishing rate of each of the layer and the third filling layer is set.

(Appendix 5)
The first filling layer and the second filling layer include silicon oxide and are formed by a sputtering method, and the first filling layer and the second filling layer are formed by an oxygen gas partial pressure ratio of the sputtering method. The method of manufacturing a magnetic storage medium according to appendix 1, wherein the polishing rate for each of the filling layers is set.

(Appendix 6)
The magnetic storage medium manufacturing method according to appendix 5, wherein the polishing step is a polishing step by a chemical mechanical polishing method using abrasive grains containing CeO.

(Appendix 7)
The first filling layer, the second filling layer, and the third filling layer include silicon oxide, are formed by a sputtering method, and the first filling layer has a first oxygen gas partial pressure ratio of the first sputtering method. The method of manufacturing a magnetic storage medium according to appendix 2, wherein the polishing rates of the filling layer, the second filling layer, and the third filling layer are set.

(Appendix 8)
The method of manufacturing a magnetic storage medium according to appendix 7, wherein the polishing step is a polishing step by a chemical mechanical polishing method using abrasive grains containing CeO.

(Appendix 9)
When the film pressures of the first filling layer and the second filling layer are tF1 and tF2, respectively, and the groove depth of the recess is d, the layers are laminated at film pressures satisfying tF1 <d and (tF1 + tF2) ≧ d. The method for manufacturing a magnetic storage medium according to appendix 1, wherein:

(Appendix 10)
The magnetic storage medium manufacturing method according to appendix 1, wherein the magnetic storage medium includes a servo area and a data area formed by the uneven pattern.

(Appendix 11)
The method of manufacturing a magnetic storage medium according to appendix 10, wherein the data area is composed of separated magnetic recording layers.

(Appendix 12)
A magnetic storage medium manufactured by the method for manufacturing a magnetic storage medium according to any one of appendix 1 to appendix 11, a head for recording and / or reproducing information on the magnetic storage medium, and recording and reproduction of the head An information storage device comprising a control circuit for controlling operation.

  Since the second filler having a low polishing rate is provided on the first filler having a high polishing rate in order to flatten the uneven pattern forming the recording layer, a necessary portion without increasing the polishing time. Only a low polishing rate can be achieved. Thereby, high flatness of the surface can be obtained without impairing the production efficiency, the production margin, and the like.

1 Magnetic disk device (information storage device)
3 Magnetic disk (magnetic storage medium)
4 Spindle motor 5 Actuator 53 Slider 30 Substrate 32 Magnetic recording layer 34 Polishing stopper layer 36 First filling layer 38 Second filling layer 40 Third filling layer

Claims (6)

In a method for manufacturing a magnetic storage medium,
Forming a recording layer on the substrate;
A predetermined uneven pattern on the recording layer;
Forming a polishing stopper layer on the protrusions of the uneven pattern;
Forming a first filling layer having a higher polishing rate than the polishing stopper layer on the recesses of the uneven pattern and the polishing stopper layer;
Forming a second filling layer having a polishing rate lower than that of the first filling layer on the first filling layer;
A method of manufacturing a magnetic storage medium, comprising: polishing the second filling layer and the first filling layer until the polishing stopper layer is exposed. A third filling layer having a polishing rate higher than that of the second filling layer is formed on the second filling layer between the step of forming the second filling layer and the polishing step. The method of manufacturing a magnetic storage medium according to claim 1, further comprising a step. The first filling layer and the second filling layer are formed by a sputtering method, and the polishing of each of the first filling layer and the second filling layer is performed by a gas pressure of the sputtering method. The method according to claim 1, wherein a rate is set. The first filling layer and the second filling layer contain silicon oxide and are formed by a sputtering method,
The method for manufacturing a magnetic storage medium according to claim 1, wherein the polishing rate of each of the first filling layer and the second filling layer is set according to an oxygen gas partial pressure ratio of the sputtering method. When the film thicknesses of the first filling layer and the second filling layer are tF1 and tF2, respectively, and the groove depth of the recess is d, the layers are stacked so as to satisfy tF1 <d and (tF1 + tF2) ≧ d. The method of manufacturing a magnetic storage medium according to claim 1. A magnetic storage medium manufactured by the method for manufacturing a magnetic storage medium according to any one of claims 1 to 5,
A head for recording and / or reproducing information with respect to the magnetic storage medium;
An information storage device comprising: a control circuit that controls recording and reproducing operations of the head.

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