JP2012155780A - Method for manufacturing magnetic recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a magnetic recording medium which can increase usable frequency of repetitive transfer of a master information carrier.SOLUTION: A method for manufacturing a magnetic recording medium includes a step for forming a medium W to be magnetically transferred by forming a magnetic layer on a substrate, a deposit removal step, and a magnetic transfer step for writing an information signal in the magnetic layer by superimposing the medium W to be magnetically transferred on a master information carrier and applying an external magnetic field from the master information carrier side. The deposit removal step includes a bonding step in which a deposit capturing plate H having a surface which is softer than a surface A to be magnetically transferred of the medium W to be magnetically transferred and does not have an adherence property is bonded to the surface A to be magnetically transferred and deposits attached to the surface A to be magnetically transferred are captured by plastic deformation of the deposit capturing plate H, and a peeling step in which the deposits are removed together with the deposit capturing plate H by peeling the deposit capturing plate H from the surface A to be magnetically transferred.

Description

  The present invention relates to a method of manufacturing a magnetic recording medium that performs magnetic transfer of an information signal to a magnetic recording medium using a master information carrier in which an information signal to be magnetically transferred to a magnetic recording medium such as a servo signal is written. The present invention relates to a method for manufacturing a magnetic recording medium capable of greatly improving the number of times that data can be repeatedly transferred by a single master information carrier.

  Currently, in a hard disk drive (hard disk drive) which is a kind of magnetic recording / reproducing apparatus, the recording density is increased by 1.5 times or more per year, and it is said that the increasing trend will continue in the future. With the increase in the recording density of hard disk devices, development of magnetic heads and magnetic recording media suitable for increasing the recording density is in progress. In the latest magnetic recording media, the track density has reached 320 kTPI.

  In a magnetic recording medium having a high track density, the tracking servo technology of the magnetic head plays an important role in order to accurately scan the magnetic head over the track. In current hard disk drives, information signals such as servo signals for tracking and servo signals such as address information signals and reproduction clock signals are recorded at regular angular intervals during one round of the disk. Control is performed to correct the position of the magnetic head so that the magnetic head accurately scans the track while detecting the position of the magnetic head based on these information signals reproduced at regular intervals from the magnetic head. It has been broken.

The servo signal and the like described above serve as a reference signal for the magnetic head to accurately scan the track. For this reason, high positioning accuracy is required for writing servo signals and the like.
In a conventional hard disk drive manufacturing site, a servo signal recording device (hereinafter referred to as a servo writer) incorporating a highly accurate position detection device is used to write a servo signal to a magnetic recording medium. In general, the servo writer has a structure in which a large number of magnetic recording media are chucked on one spindle and servo signals and the like are simultaneously written on the multiple magnetic recording media in order to increase productivity.

When writing a servo signal using a servo writer, it takes a long time to write a signal over a large number of tracks while positioning the magnetic head with high accuracy, and there is a problem that productivity is low. In order to solve this problem, the number of magnetic recording media on which servo signals are simultaneously written may be increased.
However, if the number of servo writers is increased in order to increase the number of magnetic recording media on which servo signals are simultaneously written, a large cost is required for maintenance and management of the servo writers. Also, if the length of the servo writer spindle is increased and the number of magnetic recording media that can be chucked at the same time is increased, the magnetic recording medium is more likely to blur when writing servo signals, and the servo signal writing accuracy to the magnetic recording media is improved. descend. For this reason, there is a limit to the number of magnetic recording media that can be chucked on one spindle, and it has been difficult to increase the number of magnetic recording media that can be chucked simultaneously.

Further, the problem in increasing the number of servo writers described above and the problem in increasing the number of magnetic recording media that can be chucked at the same time become more serious as the track density of the magnetic recording medium increases and the number of tracks increases.
Thus, a technique for writing a servo signal or the like on a magnetic recording medium without using a servo writer has been proposed. Specifically, the information signal written on the master information carrier is magnetically recorded by superimposing a master information carrier on which an information signal such as a servo signal is written and a magnetic recording medium, and applying energy for transfer from the outside. Techniques for magnetic transfer to a medium have been proposed.

For example, in Patent Document 1, a master information carrier surface in which a concavo-convex shape corresponding to an information signal is formed on the surface of a base is brought into contact with the surface of a magnetic recording medium, thereby corresponding to the concavo-convex shape on the surface of the master information carrier. A technique for recording a magnetization pattern to be recorded on a magnetic recording medium is described.
When performing magnetic transfer of an information signal to a magnetic recording medium using a master information carrier in which an information signal such as a servo signal to be magnetically transferred to the magnetic recording medium is written, magnetic recording is performed as compared to using a servo writer. The information signal can be written to the medium in a short time.

JP 10-40544 A JP 2009-252282 A

  A master information carrier on which an information signal used for magnetic transfer is written is very expensive. However, the master information carrier can be used repeatedly when transferring an information signal to a magnetic recording medium. For this reason, the number of times that the master information carrier can be repeatedly used for magnetic transfer (the number of times it can be used) is increased to lower the manufacturing unit price of the magnetic recording medium, and the master information for commercial production of the magnetic recording medium on which the information signal is written. There is a need to be able to apply the carrier.

As a method of increasing the number of times the master information carrier can be used, a method of suppressing the wear of the surface of the master information carrier by cleaning the surface of the magnetic recording medium or the master information carrier before performing magnetic transfer. Can be considered.
As a method for cleaning the surface of the magnetic recording medium, for example, as described in Patent Document 2, there is a method using an adhesive sheet.

  However, when the surface of the magnetic recording medium or the master information carrier is cleaned using the adhesive sheet, the adhesive material of the adhesive sheet adheres to the magnetic recording medium or the like, and when performing magnetic transfer, the magnetic recording medium and the master information carrier There is a risk that the adhesive will be transferred between the magnetic recording medium and the magnetic recording medium or the like. For this reason, it has been difficult to sufficiently increase the number of times the master information carrier can be used even if a technique for cleaning the surface of a magnetic recording medium or the like is used.

  The present invention has been proposed in view of such conventional circumstances, and deposits adhered to the surface of a magnetic recording medium on which an information signal is written by magnetic transfer using a master information carrier that is repeatedly used. It is an object of the present invention to provide a method for manufacturing a magnetic recording medium that can improve the number of times that the master information carrier can be repeatedly transferred.

  In order to solve the above-mentioned problems, the present inventors have conducted intensive studies focusing on the deposits that adhere to the magnetic recording medium and the master information carrier. As a result, it has been found that among the deposits adhering to the magnetic recording medium and the like, there are many deposits due to hard carbon used for the protective layer of the magnetic recording medium as the deposits that damage the master information carrier. Further, it has been found that hard carbon tends to adhere as an adherent to the surface of a magnetic recording medium or the like because it is electrically insulating and has static electricity. Furthermore, the hard carbon adhering to the magnetic recording medium as a deposit may be swept to the outer edge of the magnetic recording medium in the wiping process with respect to the surface of the magnetic recording medium. It was found that the hard carbon that was re-moved to cause damage to the master information carrier.

  Accordingly, the present inventors have focused on the hard carbon adhering to the magnetic recording medium and the master information carrier, and have made studies as described below. As a result, the deposit made of hard carbon used for the protective layer of the magnetic recording medium has a hard and rugged shape, and can be efficiently captured by being embedded in a soft material that is plastically deformed. I found out. From this, the present inventors can remove deposits such as hard carbon from a magnetic recording medium or the like without using an adhesive, and can improve the number of times the master information carrier can be repeatedly transferred. The manufacturing method was completed.

That is, the present invention provides the following means.
(1) A step of forming a magnetic transfer medium by forming a magnetic layer on a substrate, a deposit removal step of removing deposits adhering to the magnetic transfer surface of the magnetic transfer medium, and information The magnetic transfer medium is superimposed on the master information carrier on which a transfer pattern corresponding to the signal is formed, the magnetic transfer surface is opposed to the master information carrier, and an external magnetic field is applied from the master information carrier side, A magnetic transfer step of writing an information signal to the magnetic layer of the magnetic transfer medium, wherein the deposit removal step has a surface that is softer and less sticky than the magnetic transfer surface. A bonding step of attaching the adhered matter to the magnetic transfer surface and capturing the adhered matter adhering to the magnetically transferred surface by plastic deformation of the attached matter capturing plate; and By peeling can manufacturing method of a magnetic recording medium characterized by having a peeling step of removing the deposits together with the deposit capture plate.

(2) Forming a magnetic transfer medium by forming a magnetic layer on the substrate, and removing deposits adhering to the magnetic transfer surface of the master information carrier on which the transfer pattern corresponding to the information signal is formed Depositing the magnetic transfer medium on the master information carrier with the magnetic transfer surface facing the master information carrier, applying an external magnetic field from the master information carrier side, and A magnetic transfer step of writing an information signal to the magnetic layer of the magnetic transfer medium, and the deposit removing step has a surface that is softer and less sticky than the magnetic transfer surface. A bonding step of attaching the adhering matter adhering to the magnetic transfer surface by plastic deformation of the adhering matter capturing plate, and peeling off the adhering matter capturing plate from the magnetic transfer surface. It the method of manufacturing a magnetic recording medium characterized by having a peeling step of removing the deposits together with the deposit capture plate.

(3) The method for manufacturing a magnetic recording medium according to (1) or (2), wherein the deposit capturing plate is made of a metal material.
(4) The manufacturing method of the magnetic recording medium according to (3), wherein the deposit capturing plate is made of any one selected from the group consisting of aluminum, copper, gold, or an alloy thereof. Method.
(5) The method for manufacturing a magnetic recording medium according to any one of (1) to (4), wherein the deposit removing step is performed in a reduced pressure environment.

  In the method for producing a magnetic recording medium of the present invention, a deposit capturing plate having a softer surface than the magnetic transfer surface or the magnetic transfer surface of the master information carrier is attached to the magnetic transfer surface or the magnetic transfer surface of the master information carrier. In addition, a bonding step of capturing the deposit adhered to the transfer surface by plastic deformation of the deposit capture plate, and peeling the deposit capture plate from the magnetic transfer surface or the magnetic transfer surface of the master information carrier. Therefore, it is a method comprising a deposit removing step having a peeling step for removing the deposit together with the deposit capturing plate, so that the magnetic recording medium serving as the magnetic recording medium or the hard attached to the master information carrier Deposits made of carbon or the like can be effectively removed from the magnetic transfer medium without using an adhesive.

  Therefore, a magnetic transfer medium is superposed on a master information carrier on which a transfer pattern corresponding to an information signal is formed, and the magnetic transfer surface is opposed to the master information carrier, and an external magnetic field is applied from the master information carrier side. In the magnetic transfer step of writing an information signal to the magnetic layer of the magnetic transfer medium, the deposits are transferred between the magnetic recording medium and the master information carrier to prevent the magnetic recording medium and the master information carrier from being contaminated. it can.

  In the method for producing a magnetic recording medium of the present invention, the deposit capturing plate having a surface softer than the magnetic transfer surface or the magnetic transfer surface of the master information carrier and capable of trapping deposits by plastic deformation is used. Therefore, when the hard carbon used as the protective layer of the magnetic recording medium is attached to the transfer surface, the deposits attached to the magnetic transfer surface can be effectively removed. As a result, the number of times that the master information carrier can be repeatedly transferred can be improved.

FIG. 1 is a diagram for explaining an example of a method for manufacturing a magnetic recording medium according to the present invention, and is a schematic cross-sectional view showing an example of a magnetic transfer medium. FIG. 2 is a diagram for explaining an example of a method for manufacturing a magnetic recording medium according to the present invention, and is a schematic cross-sectional view showing a situation in which a deposit removal process is performed. FIG. 3 is a diagram for explaining an example of the method for producing a magnetic recording medium of the present invention, and is a schematic cross-sectional view showing a situation in which a magnetic transfer process is performed.

  Hereinafter, a method for producing a magnetic recording medium of the present invention will be described in detail with reference to the drawings. In the drawings used in the following description, in order to make the features easy to understand, the portions that become the features may be schematically shown for convenience, and the dimensional ratios of the portions are not always the same as the actual ones.

"Method of manufacturing magnetic recording medium"
1 to 3 are diagrams for explaining an example of a method of manufacturing a magnetic recording medium according to the present invention. The method for manufacturing a magnetic recording medium according to this embodiment includes a step of forming a magnetic transfer medium, a deposit removing step, and a magnetic transfer step. FIG. 1 is a schematic cross-sectional view showing an example of a magnetic transfer medium, FIG. 2 is a schematic cross-sectional view showing a situation in which a deposit removal process is being performed, and FIG. 3 is a magnetic transfer process. It is the cross-sectional schematic diagram which showed the situation which is.

The step of forming the magnetic transfer medium is a step of forming the magnetic layer 201 on which information signals are written in the magnetic transfer step on the substrate 200. In the present embodiment, in the step of forming the magnetic transfer medium W, as shown in FIG. 2, the magnetic transfer medium W having the magnetic layer 201 formed on one surface of the substrate 200 is formed.
In this embodiment, in the process of forming the magnetic transfer medium W, the magnetic transfer medium W shown in FIG. 1 is formed. However, in order to make the drawing easy to see, only the substrate 200 and the magnetic layer 201 are shown in FIG. The detailed laminated structure and manufacturing method of the magnetic transfer medium W shown in FIG. 1 will be described later.

  In this embodiment, a wiping step and / or a burnishing step may be performed after the step of forming the magnetic transfer medium and before the deposit removing step.

The wiping step can be, for example, a step of wiping the magnetic transfer surface A by pressing a wiping tape against the magnetic transfer surface A of the rotated magnetic transfer medium W. By performing the wiping step, it is possible to remove spatter dust and the like adhering to the magnetic transfer surface A of the magnetic transfer medium W, so that the magnetic transfer surface A can be cleaned and the flying height of the magnetic head Can be made smaller.
As the wiping tape used in the wiping step, for example, a wiping tape obtained by slitting a cloth made of ultrafine fibers into a belt shape, a woven or knitted fabric of ultrafine fiber multifilament yarn, and the like can be used.

  The burnishing step can be a step of polishing the magnetic transfer surface A by pressing a polishing tape against the magnetic transfer surface A of the rotated magnetic transfer medium W, for example. By performing the burnishing process, abnormal projections and minute dusts on the magnetic transfer surface A of the magnetic transfer medium W can be removed, and the magnetic transfer surface A is smoothed. Accordingly, the flying height of the magnetic head in the hard disk drive can be further reduced, and a gap is generated between the magnetic transfer medium W and the master information carrier M in the magnetic transfer process, resulting in a blurred transfer pattern. It is possible to prevent the master information carrier M from being damaged.

Examples of the polishing tape (burnish tape) used in the burnishing process include a tape in which an abrasive layer is formed on a polyester base film.
As the abrasive used when forming the abrasive layer, chromium oxide, α-alumina, silicon carbide, nonmagnetic iron oxide, diamond, γ-alumina, α, and the like having an average particle diameter of about 0.05 μm to 50 μm. γ-alumina, fused alumina, corundum, artificial diamond and the like can be mentioned.

  The deposit removal step is a step of removing deposits adhering to the transfer surface of the magnetic recording medium or the master information carrier. In this step, the deposit capturing plate is attached to the transfer surface of the magnetic recording medium or the master information carrier. And a step of peeling off the deposit capturing plate from the transfer surface. Since the deposit removal process is almost the same for the magnetic recording medium and the master information carrier, the following description is mainly for the magnetic recording medium.

  In the present embodiment, in the deposit removing step, the deposit capturing plate H is bonded to the magnetic transfer surface A of the magnetic transfer medium W and adhered to the magnetic transfer surface A as shown in FIG. And a peeling step of removing the deposit together with the deposit capturing plate H by peeling off the deposit capturing plate H from the magnetic transfer surface A. Do.

  In the bonding step and the peeling step, for example, the deposit capturing plate H and the magnetic transfer using a device similar to the device that holds the magnetic transfer medium W and the master information carrier M when performing the magnetic transfer step. By holding the medium W, the attachment capturing plate H and the magnetic transfer medium W can be bonded together, and the attachment capturing plate H and the magnetic transfer medium W can be peeled off.

  The deposit removal step is preferably performed under a reduced pressure environment. When the deposit removal process is performed in a reduced pressure environment, the magnetic transfer medium W and the deposit trapping plate H are adsorbed in the deposit removal process, and the deposit trapping plate H is peeled off from the magnetic transfer medium W. It can prevent becoming difficult and can perform a deposit | attachment removal process efficiently.

The deposit capturing plate H is softer than the magnetic transfer surface A of the magnetic transfer medium W and has a plastically deformed surface. In addition, as in the case of a conventionally used adhesive tape, the surface of the adhering material capturing plate H does not have adhesiveness so that the adhering material does not adhere to the magnetic transfer surface A even if it is a small amount. To. In the present invention, “softer than the magnetic transfer surface A of the magnetic transfer medium W” means more specifically softer than the carbon film used as the protective layer of the magnetic transfer medium W. Further, when the deposit removal process is performed on the master information carrier, it means to make it softer than the transfer surface of the master information carrier. More specifically, the surface of the master information carrier is covered with a carbon protective film. In some cases, it is softer than the carbon film.
The surface of the deposit capturing plate H is preferably excellent in flatness so that the deposit adhered to the magnetic transfer surface A can be effectively captured. Specifically, it is preferable that the surface of the deposit capturing plate H is as flat as the magnetic transfer surface A.

  The deposit capturing plate H can have the same shape as that of the magnetic transfer medium W in plan view, as shown in FIG. Note that the planar shape of the deposit capturing plate H is not limited to the same shape as the planar view of the magnetic transfer medium W. For example, the outline shape of the magnetic transfer medium W is superimposed on the magnetic transfer medium W. It may have a shape having a larger plane area than the magnetic transfer medium W in which the outline of the deposit capturing plate H is disposed outside.

  Further, as the deposit capturing plate H, it is preferable to use a material made of a metal material. The deposit capturing plate H made of a metal material has deposits made of the material constituting the deposit capturing plate H remaining on the magnetic transfer surface A of the magnetic transfer medium W after the deposit removing step is completed. This is preferable. Moreover, by making the deposit capturing plate H a conductive metal material, generation of static electricity can be prevented, and charged deposits such as hard carbon powder can be easily captured.

  Further, specifically, the metal material used for the deposit capturing plate H is preferably made of any one selected from the group consisting of aluminum, copper, gold, or alloys thereof. The deposit capturing plate H made of these materials is soft and easily plastically deforms and adheres to the magnetic transfer surface A so that the deposit can be captured more easily and efficiently on the magnetic transfer surface A. The attached deposits can be removed more effectively. The deposit capturing plate H of the present invention may be formed as a metal thin film by sputtering, vacuum deposition, electroplating, or the like on the surface of the base plate in addition to the above metal material. In this case, the film thickness of the thin film is larger than the particle size of the deposit, and preferably about several times the particle size of the deposit so that the thin film can be easily plastically deformed.

  The deposit capturing plate H can be used repeatedly. In addition, it is preferable to exchange the deposit capturing plate H every time the deposit removing step is performed about 5000 times so that the deposit adhered to the magnetic transfer surface A can be effectively captured.

Next, a magnetic transfer step of writing an information signal is performed on the magnetic transfer medium W from which the deposits obtained after the deposit removal step are removed.
In the magnetic transfer process, first, the signal recording surface which is the magnetic transfer surface A of the magnetic transfer medium W is initially magnetized. The initial magnetization is performed by applying an initial DC magnetic field in one direction in the track direction when an in-plane magnetic recording medium is manufactured as a magnetic recording medium, and when a perpendicular magnetic recording medium is manufactured, the magnetic transfer surface A Is performed by applying an initial DC magnetic field in one direction perpendicular to.

  The initial DC magnetic field can be applied to the magnetic transfer medium W using a permanent magnet or an electromagnet. As the permanent magnet, it is preferable to use an NdFeB-based sintered magnet that is more stable and has a strong magnetic force. The application of the initial DC magnetic field is preferably performed in a non-contact state with the magnetic transfer medium W in order to maintain the cleanliness of the magnetic transfer surface A of the magnetic transfer medium W.

  In the magnetic transfer step, as shown in FIG. 3, a master information carrier M on which a transfer pattern corresponding to an information signal is formed is prepared. As the master information carrier M, for example, as shown in FIG. 3, a Ni base 100 having convex portions 100 a and concave portions 100 b formed on the surface, and a magnetic layer formed on one surface of the Ni base 100 101 can be mentioned. Further, as another example of the master information carrier M, for example, one in which the magnetic layer 101 is embedded in the recess 100b of the master information carrier M shown in FIG.

The master information carrier M shown in FIG. 3 can be manufactured by, for example, the following method.
First, an electron beam resist is applied to the surface of the wafer by spin coating. Next, using an electron beam exposure apparatus, the electron beam resist is irradiated with an electron beam modulated in accordance with a servo signal or the like, and the resist is exposed and developed. Thereafter, a resist pattern corresponding to a transfer pattern for writing an information signal to the magnetic transfer medium W is formed on the wafer by removing the unexposed portion. Examples of the transfer pattern include patterns corresponding to information signals such as a pre-servo signal and a self-servo signal for generating a servo signal in the hard disk drive in addition to the servo signal of the hard disk drive.

Next, a reactive etching process is performed on the wafer using the resist pattern as a mask, and a portion of the wafer not masked with the resist is dug down. After this etching process, the master pattern for manufacturing the master information carrier M is obtained by removing the resist pattern remaining on the wafer with a solvent.
Next, a conductive layer made of Ni with a thickness of about 10 nm is formed on the master by sputtering. Thereafter, a Ni layer having a thickness of several microns is formed on the master by electroforming using the master on which the conductive layer is formed. Then, by removing the Ni layer from the master and cleaning, the Ni base material 100 having the convex portions 100a and the concave portions 100b formed on the surface is obtained as shown in FIG.

  Next, the magnetic layer 101 is formed on the surface of the Ni substrate 100. As the magnetic layer 101, the same magnetic layer used for the magnetic transfer medium W can be formed. Of the magnetic layer 101 formed on the surface of the Ni substrate 100, the magnetic layer 101 in the portion where the convex portion 100a is formed is used for magnetic transfer to the magnetic transfer medium W, and the concave portion 100b is formed. Since the formed magnetic layer 101 is not in contact with the magnetic transfer medium W, it is not used for magnetic transfer.

Furthermore, a protective film (not shown) made of a hard carbon film or the like having a thickness of about several nm may be formed on the surface of the Ni base 100 on which the magnetic layer 101 shown in FIG. 3 is formed. By providing the protective film, the wear resistance of the master information carrier M can be enhanced.
Through the above steps, a master information carrier M on which a transfer pattern corresponding to the information signal shown in FIG. 3 is formed is obtained.

Next, as shown in FIG. 3, the surface of the master information carrier M on the magnetic layer 101 side and the magnetic transfer surface A of the magnetic transfer medium W are opposed to each other, and the master transfer carrier W is placed on the master information carrier M. In contact with each other with a predetermined pressing force. Thereafter, as shown in FIG. 3, an external magnetic field is applied from the opposite side of the transfer surface of the master information carrier M using the magnetic field generating means G while moving the magnetic field generating means G relatively in the track direction X. Thus, an information signal is written into the magnetic layer of the magnetic transfer medium W. This external magnetic field for transfer is a magnetic field in the opposite direction to the initial DC magnetic field. Thereby, in the magnetic transfer medium W, magnetization reversal occurs at a position facing the transfer pattern of the master information carrier M, and a magnetization pattern corresponding to a servo signal or the like is written.
Through the above steps, a magnetic recording medium in which an information signal is written is obtained.

  In the present embodiment, a glide test is performed on the magnetic recording medium thus obtained. The glide inspection is a process for inspecting the surface of the magnetic recording medium for projections. In other words, when recording / reproducing is performed on a magnetic recording medium using a magnetic head, if there is a protrusion on the surface of the magnetic recording medium that is higher than the flying height (the distance between the medium and the magnetic head), the magnetic head May cause damage to the magnetic head or defects in the magnetic recording medium. In the glide inspection, the presence or absence of such high protrusions is inspected.

Usually, a certification test is performed on a magnetic recording medium that has passed the glide test. The certification inspection is similar to normal hard disk drive recording / reproduction, after a predetermined signal is recorded on the magnetic recording medium with a magnetic head, the signal is reproduced, and the resulting reproduction signal is used to record the magnetic recording medium. Impossibility is detected, and the quality of the medium, such as the electrical characteristics of the magnetic recording medium W and the presence or absence of defects, is confirmed.
Note that the magnetic recording medium manufactured in this embodiment is different from the conventional certification test because an information signal such as a servo signal is already written. That is, using a servo signal or the like magnetically transferred to a magnetic recording medium, a test is performed in which the magnetic head is positioned at a specific location and reading / writing is performed.

In the magnetic transfer process of the present embodiment, an electromagnet or a permanent magnet can be used as the magnetic field generating means G. Further, the magnetic field generating means G shown in FIG. 3 can be rotated in the track direction X from the center of the magnetic transfer medium W while generating an external magnetic field in the same direction in the radial direction of the magnetic transfer medium W. It has become.
In the magnetic transfer process of the present embodiment, when an in-plane magnetic recording medium is manufactured as a magnetic recording medium, an external magnetic field for transfer is generated in the other direction in the track direction by the magnetic field generating means G to manufacture a perpendicular magnetic recording medium. In this case, the magnetic field generating means G generates an external magnetic field for transfer in the other direction perpendicular to the magnetic transfer surface A.

  When a plurality of magnetic recording media W are manufactured by writing information signals to a plurality of magnetic transfer media W using a single master information carrier M, the number of times that the master information carrier can be repeatedly transferred can be effectively improved. Therefore, it is preferable to perform the deposit removing process on the magnetic transfer medium W used for manufacturing all the magnetic recording media, but the deposit removing process is performed only on a part of the magnetic transfer medium W. May be. In addition, it is preferable to perform the deposit removal process on the master information carrier for each magnetic transfer process, but the deposit removal process may be performed every predetermined number of times. Even when the deposit removal process is performed only on a part of the magnetic transfer medium W or every predetermined magnetic transfer process, the master information carrier is compared with the case where the deposit removal process is not performed. The number of usable times that can be repeatedly transferred can be improved. In addition, when the deposit removal process is performed for each of the magnetic transfer media W and every predetermined magnetic transfer process, compared to the case where the deposit removal process is performed for all the magnetic transfer media W, etc. A magnetic recording medium can be manufactured efficiently and the productivity of the magnetic recording medium can be improved.

  In the method for manufacturing a magnetic recording medium according to the present embodiment, the deposit capturing plate H having a softer surface than the transfer surface (the magnetic transfer surface A of the magnetic transfer medium W or the magnetic transfer surface of the master information carrier M) is transferred to the transfer surface. And a depositing step for capturing deposits adhered to the transfer surface by plastic deformation of the deposit capturing plate H, and peeling the deposit capturing plate H from the transfer surface, thereby depositing the deposits together with the deposit capturing plate H. Since there is a deposit removing step having a peeling step for removing the deposit, the deposit made of hard carbon or the like adhering to the transfer surface of the magnetic recording medium or the master information carrier can be used without using an adhesive. It can be effectively removed from the transfer surface.

  Accordingly, the magnetic transfer medium W is superimposed on the master information carrier M on which the transfer pattern corresponding to the information signal is formed, and the magnetic transfer surface A is opposed to the master information carrier M, and the external magnetic field is transferred from the master information carrier M side. In the magnetic transfer step of writing an information signal to the magnetic layer of the magnetic transfer medium W, the deposit is transferred between the magnetic recording medium W and the master information carrier M, and the magnetic recording medium W and the master information carrier It is possible to prevent M from being contaminated.

  In the method for manufacturing a magnetic recording medium according to the present embodiment, since the deposit capturing plate has a surface softer than the transfer surface and capable of trapping deposits by plastic deformation, the magnetic recording medium is used on the transfer surface. When the hard carbon used for the protective layer adheres, the deposits adhering to the transfer surface can be effectively removed. As a result, the number of times that the master information carrier M can be repeatedly transferred can be improved, and the production cost of the magnetic recording medium can be greatly reduced.

  Further, in the method for manufacturing a magnetic recording medium described above, in the step of forming the magnetic transfer medium, as shown in FIG. 2, the magnetic transfer medium W having the magnetic layer 201 formed on one surface of the substrate 200 is formed. However, a magnetic transfer medium in which the magnetic layer 201 is formed on both surfaces of the substrate 200 may be formed. When the magnetic layer 201 is formed on both surfaces of the substrate 200, the magnetic layer formed on one surface and the magnetic layer formed on the other surface may be the same or different.

When the magnetic transfer medium having the magnetic layer 201 formed on both surfaces of the substrate 200 is formed, the magnetic transfer surface A is formed on both surfaces of the magnetic transfer medium. Remove deposits on both sides.
In addition, when a magnetic transfer process for writing information signals to a magnetic transfer medium having the magnetic layer 201 formed on both surfaces of the substrate 200 is performed, it is preferable to write information signals on both surfaces of the magnetic recording medium by the following method. .

That is, a pair of master information carriers M are opposed to each other with the surface on the magnetic layer 101 side facing inward, and a magnetic transfer medium having a magnetic layer 201 formed on both surfaces is sandwiched between the pair of master information carriers M. The master information carrier M and the magnetic transfer medium are brought into close contact with each other with a predetermined pressing force while being in contact with each other. Thereafter, an external magnetic field is applied from the side opposite to the transfer surface of the master information carrier M using the magnetic field generating means G. As a result, magnetization patterns corresponding to servo signals and the like are written on both surfaces of the magnetic transfer medium.
Even if the magnetic transfer medium has the magnetic layer 201 formed on both sides of the substrate 200, if the information signal to be magnetically transferred is pre-servo information or self-servo information, the information signal is written only on one side of the magnetic recording medium. be able to.

"Magnetic transfer media"
Next, the magnetic transfer medium W formed in the magnetic recording medium manufacturing method of the present embodiment will be described in detail with reference to FIG. FIG. 1 is a schematic cross-sectional view showing an example of a magnetic transfer medium W. A magnetic transfer medium W shown in FIG. 1 includes a soft magnetic underlayer 32 including two soft magnetic layers 32a antiferromagnetically coupled to a nonmagnetic substrate (substrate) 31 by a spacer layer 32b, and an orientation control layer. 33, a nonmagnetic underlayer 38, a perpendicular magnetic layer 34, a protective layer 35, and a lubricant film 36 are sequentially laminated.

  The perpendicular magnetic layer 34 includes three layers of a lower magnetic layer 34a, an intermediate magnetic layer 34b, and an upper magnetic layer 34c, and a nonmagnetic layer 37a is sandwiched between the magnetic layer 34a and the magnetic layer 34b. In addition, since the nonmagnetic layer 37b is sandwiched between the magnetic layer 34b and the magnetic layer 34c, the magnetic layers 34a to 34c and the nonmagnetic layers 37a and 37b are alternately stacked.

  As the nonmagnetic substrate 31, for example, a metal substrate made of a metal material such as aluminum or an aluminum alloy may be used. For example, a nonmetal made of a nonmetal material such as glass, ceramic, silicon, silicon carbide, carbon, or the like. A substrate may be used. Moreover, you may use what formed the NiP layer or the NiP alloy layer on the surface of these metal board | substrates and non-metal board | substrates, for example using the plating method or the sputtering method.

As the glass substrate, for example, amorphous glass or crystallized glass can be used. As the amorphous glass, for example, general-purpose soda lime glass or aluminosilicate glass can be used. In addition, as the crystallized glass, for example, lithium-based crystallized glass can be used.
As the ceramic substrate, for example, a general-purpose aluminum oxide, a sintered body mainly composed of aluminum nitride, silicon nitride, or the like, or a substrate made of these fiber reinforcements can be used.

  The nonmagnetic substrate 31 has an average surface roughness (Ra) of 1 nm (10 mm) or less, preferably 0.5 nm or less, from the viewpoint of suitable for high recording density recording with a magnetic head flying low. preferable. Further, it is preferable that the surface fine waviness (Wa) is 0.3 nm or less (more preferably 0.25 nm or less) from the viewpoint of being suitable for high recording density recording with the magnetic head flying low. In addition, it is possible to use a magnetic head having a chamfered portion at the end face and a surface average roughness (Ra) of at least one of the side surface portion of 10 nm or less (more preferably 9.5 nm or less). Preferred for stability. In addition, microwaviness (Wa) can be measured as surface average roughness in a measuring range of 80 μm, for example, using a surface roughness measuring device P-12 (manufactured by KLM-Tencor).

  Further, when the non-magnetic substrate 31 is disposed in contact with the soft magnetic underlayer 32 mainly composed of Co or Fe, corrosion proceeds due to surface adsorption gas, influence of moisture, diffusion of substrate components, and the like. there's a possibility that. For this reason, it is preferable to provide an adhesion layer between the nonmagnetic substrate 31 and the soft magnetic underlayer 32. By providing an adhesion layer between the nonmagnetic substrate 31 and the soft magnetic underlayer 32, the progress of corrosion can be suppressed. As a material for the adhesion layer, for example, Cr, Cr alloy, Ti, Ti alloy and the like can be selected as appropriate. The thickness of the adhesion layer is preferably 2 nm (20 mm) or more.

As the soft magnetic layer 32a, a material containing Fe: Co in the range of 40:60 to 70:30 (atomic ratio) is preferably used. In order to increase the magnetic permeability and corrosion resistance of the soft magnetic layer 32a, it is preferable to contain any one selected from Ta, Nb, Zr, and Cr in the range of 1 to 8 atomic%.
As the spacer layer 32b, Ru, Re, Cu, or the like can be used, and it is particularly preferable to use Ru.

  The orientation control layer 33 is for improving the recording / reproducing characteristics by refining the crystal grains of the perpendicular magnetic layer 34. The orientation control layer 33 is not particularly limited, but it is preferable to use a layer having an hcp structure, an fcc structure, or an amorphous structure. In particular, it is preferable to use a Ru alloy, a Ni alloy, a Co alloy, a Pt alloy, or a Cu alloy. The orientation control layer 33 may be a multilayer of the above alloy. Specifically, for example, a multilayer structure of Ni-based alloy and Ru-based alloy, a multilayer structure of Co-based alloy and Ru-based alloy, and a multilayer structure of Pt-based alloy and Ru-based alloy from the nonmagnetic substrate 31 side. It is preferable that

  In the initial portion of the perpendicular magnetic layer 34 immediately above the orientation control layer 33, disorder of crystal growth that causes noise is likely to occur. For this reason, it is preferable to provide a nonmagnetic underlayer 38 between the orientation control layer 33 and the perpendicular magnetic layer 34. The occurrence of noise can be suppressed by replacing the initial portion of the perpendicular magnetic layer 34 where the crystal growth is disturbed with the nonmagnetic underlayer 38.

As the nonmagnetic underlayer 38, it is preferable to use a layer made of a material containing Co as a main component and further containing an oxide. The Cr content in the nonmagnetic underlayer 38 is preferably 25 atomic% or more and 50 atomic% or less. As the oxide contained in the nonmagnetic underlayer 38, for example, an oxide such as Cr, Si, Ta, Al, Ti, Mg, Co is preferably used, and among them, TiO ₂ , Cr ₂ O ₃ , SiO are particularly preferable. ₂ etc. can be used suitably. The content of the oxide of the nonmagnetic underlayer 38 is 3 mol% or more and 18 mol% or less with respect to the total mol amount calculated as one compound of, for example, an alloy such as Co, Cr, and Pt constituting the magnetic particles. It is preferable.

The magnetic layers 34a and 34b preferably have a granular structure, and it is preferable to use a material mainly containing Co and further containing an oxide. As the oxides included in the magnetic layers 34a and 34b, for example, oxides such as Cr, Si, Ta, Al, Ti, Mg, and Co are preferably used, and in particular, TiO ₂ , Cr ₂ O ₃ , and SiO _{2 are used.} Etc. are preferably used.
The lower magnetic layer 34a preferably contains a composite oxide to which two or more kinds of oxides are added. Among these, Cr ₂ O ₃ —SiO ₂ , Cr ₂ O ₃ —TiO ₂ , Cr ₂ O ₃ —SiO ₂ —TiO _{2 and the} like can be preferably used.

As a material suitable for the magnetic layers 34a and 34b, for example, 90 (Co14Cr18Pt) -10 (SiO ₂ ) {Cr content of 14 atomic%, Pt content of 18 atomic%, and the remainder Co magnetic particles as one compound. calculated molarity 90 mol%, 10 _mol% oxide composition consisting _{SiO 2}, 92 (Co10Cr16Pt)} -8 (SiO 2), other _{94 (Co8Cr14Pt4Nb) -6 (Cr 2} O 3), (CoCrPt) - _{(Ta 2 O 5), (} CoCrPt) - (Cr 2 O 3) - (TiO 2), (CoCrPt) - (Cr 2 O 3) - (SiO 2), (CoCrPt) - (Cr 2 O 3) - _{(SiO 2) - (TiO 2} ), (CoCrPtMo) - (TiO), (CoCrPtW) - (TiO 2), (CoCrPtB) _{(Al 2 O 3), (} CoCrPtTaNd) - (MgO), (CoCrPtBCu) - (Y 2 O 3), (CoCrPtRu) - can be exemplified compositions such as (SiO _2).

  The upper magnetic layer 34c is preferably a magnetic layer containing no oxide. Specific examples of materials suitable for the upper magnetic layer 34c include materials obtained by removing oxides from materials suitable for the magnetic layers 34a and 34b described above.

  The perpendicular magnetic layer 34 may be composed of four or more magnetic layers. For example, a magnetic layer having a granular structure may be formed by adding one layer to the magnetic layers 34a and 34b to form three layers, and a perpendicular magnetic layer having a four-layer structure in which a magnetic layer 34c containing no oxide is provided thereon. Alternatively, a perpendicular magnetic layer 34 having a four-layer structure in which a magnetic layer 34c not containing an oxide is provided as a two-layer structure on the granular magnetic layers 34a and 34b may be used.

  In addition, nonmagnetic layers 37 a and 37 b are preferably provided between three or more magnetic layers constituting the perpendicular magnetic layer 34. By providing the nonmagnetic layers 37a and 37b with an appropriate thickness, magnetization reversal of individual films can be facilitated, and dispersion of magnetization reversal of the entire magnetic particles can be reduced. As a result, the S / N ratio can be further improved. Conventionally known materials can be used for the nonmagnetic layers 37a and 37b, and for example, Ru, Re, Cu, or the like can be used.

  In addition, nonmagnetic layers 37 a and 37 b are preferably provided between three or more magnetic layers constituting the perpendicular magnetic layer 34. By providing the nonmagnetic layers 37a and 37b with an appropriate thickness, magnetization reversal of individual films can be facilitated, and dispersion of magnetization reversal of the entire magnetic particles can be reduced. As a result, the S / N ratio can be further improved. Conventionally known materials can be used for the nonmagnetic layers 37a and 37b, and for example, Ru, Re, Cu, or the like can be used.

The protective layer 35 is for preventing corrosion of the perpendicular magnetic layer 34 and preventing damage to the surface when the magnetic head contacts the magnetic recording medium. For the protective layer 35, a conventionally known material can be used. For example, a material containing C, SiO ₂ , ZrO ₂ or the like can be used. The thickness of the protective layer 35 is preferably 1 to 10 nm from the viewpoint of high recording density because the distance between the magnetic head and the magnetic recording medium can be reduced.

  The lubricating layer 36 is used to protect the surface of the magnetic recording medium when the magnetic head seeks the surface of the magnetic recording medium incorporated in the magnetic recording / reproducing apparatus (hard disk drive). Further, when the information signal is written to the magnetic layer 34 of the magnetic recording medium, the protective layer 35 has an effect of preventing the master information carrier M from coming into contact with the master information carrier M and promoting the wear. As the lubricating layer 36, a conventionally known material can be used, and for example, it can be formed by applying a lubricant such as perfluoropolyether, fluorinated alcohol, fluorinated carboxylic acid or the like on the protective layer 35.

"Method for manufacturing magnetic transfer medium"
In order to manufacture the magnetic transfer medium W shown in FIG. 1, first, an adhesion layer, a soft magnetic underlayer 32, an orientation control layer 33, a nonmagnetic underlayer 38, and perpendicular magnetism are formed on a nonmagnetic substrate 31. A layered structure forming step is performed in which the layer 34, the protective layer 35, and the lubricating layer 36 are sequentially stacked.

  The laminated structure forming step can be performed by a known method. For example, an adhesion layer, a soft magnetic underlayer 32 including a soft magnetic layer 32a, a spacer layer 32b, and a soft magnetic layer 32a, an orientation control layer 33, and a nonmagnetic underlayer are formed on the nonmagnetic substrate 31 by sputtering or the like. 38. A perpendicular magnetic layer 34 including a lower magnetic layer 34a, a nonmagnetic layer 37a, an intermediate magnetic layer 34b, a nonmagnetic layer 37b, and an upper magnetic layer 34c is laminated in this order from the bottom. Thereafter, the protective layer 35 is formed using a CVD method, an ion beam method, or the like. Next, the lubricant layer 36 is formed on the protective layer 35 by a method of applying a lubricant or the like.

Hereinafter, the effects of the present invention will be made clearer by examples. In addition, this invention is not limited to the Example shown below, In the range which does not change the summary, it can change suitably and can implement.
Example 1

<Process of forming magnetic transfer medium>
As a non-magnetic substrate, a cleaned glass substrate (manufactured by Konica Minolta Co., Ltd., 2.5 inches in outer diameter) is prepared, accommodated in a film forming chamber of a DC magnetron sputtering apparatus (C-3040 made by Anelva), and an ultimate vacuum is obtained. The film formation chamber was evacuated until the ^pressure reached 1 × 10 ⁻⁵ Pa.
Thereafter, an adhesion layer having a layer thickness of 10 nm was formed on the glass substrate using a 60Cr-40Ti target.

Next, on the adhesion layer, a target of 46Fe-46Co-5Zr-3B {Fe content 46 atom%, Co content 46 atom%, Zr content 5 atom%, B content 3 atom%} was used. A soft magnetic layer having a layer thickness of 34 nm, a Ru layer having a layer thickness of 0.76 nm, and a 46Fe-46Co-5Zr-3B soft magnetic layer having a layer thickness of 34 nm were formed at a substrate temperature of ℃ or less, and this was formed as a soft magnetic underlayer It was.
Next, a layer thickness of 5 nm (gas pressure 1 Pa) and 20 nm (gas pressure 6 Pa) is used on the soft magnetic underlayer using a Ni-6W {W content 6 atom%, the balance Ni} target and a Ru target, respectively. The film was formed in order to obtain an orientation control layer.

Then, on the orientation control layer, a magnetic layer of a multilayer structure by a sputtering method, 84 (Co12Cr16Pt) -16TiO ₂ (film thickness _{3nm), 91 (Co5Cr22Pt) -4SiO} 2 -3Cr 2 O 3 -2TiO 2 (Thickness 3 nm), Ru47.5Co (thickness 0.5 nm), and Co15Cr16Pt6B (thickness 3 nm) were laminated.

Next, a protective layer made of a carbon film having a thickness of 2.5 nm was formed by a CVD method.
Next, a lubricant layer made of perfluoropolyether was applied on the protective layer by a dipping method to form a lubricant layer having a thickness of 15 Å. The magnetic transfer medium W was obtained through the above steps.

  Next, a wiping process was performed on the magnetic transfer medium W on which the layers up to the lubricating layer were formed. The wiping process was performed by rotating the magnetic transfer medium at a rotation speed of 300 rpm and pressing the wiping tape against the magnetic transfer medium at a pressing force of 98 mN for 5 seconds while feeding the wiping tape at a feeding speed of 10 mm / second. As the wiping tape, a peelable composite fiber having a wire diameter of 2 μm made of nylon resin and polyester resin was used.

  Next, burnishing was performed on the magnetic transfer medium W that had been subjected to the wiping process. The burnishing was performed by rotating the magnetic transfer medium at a rotation speed of 300 rpm and pressing the polishing tape against the magnetic transfer medium at a pressing force of 98 mN for 5 seconds while feeding the polishing tape at a feed rate of 10 mm / second. . As the burnish tape, a film in which crystal growth type alumina particles having an average particle diameter of 0.5 μm were fixed with an epoxy resin on a polyethylene terephthalate film was used.

<Adherent removal process>
In the deposit removing process, the deposit capturing plate H is bonded to the magnetic transfer surface A of the magnetic transfer medium W, and the deposit adhering to the magnetic transfer surface A is captured by plastic deformation of the deposit capturing plate H. The sticking step to be performed and the peeling step for removing the deposits together with the deposit capturing plate H by peeling the deposit capturing plate H from the magnetic transfer surface A were performed.

As the deposit capturing plate H, one made of aluminum having the same shape as that of the magnetic transfer medium W in plan view was used. The deposit capturing plate of this example was manufactured by the following method. First, the surface of a donut-shaped aluminum alloy (5086 equivalent product) having an outer diameter of 65 mm, an inner diameter of 20 mm, and a thickness of 1.3 mm was polished for 3 minutes using alumina abrasive grains having a D50 (average particle diameter) of 0.5 μm. . Then, it polished for 10 minutes using the colloidal silica abrasive grain whose D50 is 30 nm, the average surface roughness (Ra) of the surface was 1 nm (10 cm) or less, and the fine waviness (Wa) was 0.3 nm or less.
In the deposit removing step, the deposit capturing plate was placed on one side of the magnetic recording medium in a reduced pressure atmosphere, pressed at 50 mN for 1 second, and then released. Moreover, the deposit capturing plate H was replaced every time the deposit removing step was performed 5000 times.

<Magnetic transfer process>
“Manufacture of Master Information Carrier”
A substrate made of Ni having a convex portion and a concave portion having a shape corresponding to a transfer pattern such as a pre-servo signal of 271 ktrack / inch on the surface was prepared. The track corresponding to the information signal magnetically transferred to the magnetic recording medium of the substrate has a width of 120 nm, the track interval is 60 nm, and the step between the substrate protrusion and the substrate recess (transfer pattern step) is 45 nm. there were.

On such a base material, a base layer made of a Ru film having a layer thickness of 10 nm was formed along the shape of the base material convex portions and the base material concave portions using a DC sputtering method. Thereafter, along the shape of the base convex portion and the base concave portion on the underlayer, a DC sputtering method is used to form a 70Co-5Cr-15Pt-10SiO ₂ alloy film having a thickness of 20 nm and an 80Co-5Cr layer having a thickness of 15 nm. A magnetic layer composed of a −15 Pt alloy film was sequentially laminated to form a magnetic layer in which an information signal magnetically transferred to the magnetic recording medium was written.

  Next, a protective film made of a carbon film having a thickness of 20 nm was formed on the magnetic layer by a CVD method. Through the above steps, a master information carrier M on which a transfer pattern corresponding to the information signal was formed was obtained.

Next, an information signal was written to the magnetic transfer medium W from which the deposits were removed after the deposit removing step by the following method.
First, an initial DC magnetic field of 10 kOe is applied to the magnetic transfer surface A of the magnetic transfer medium W by applying an initial DC magnetic field of 10 kOe in a direction penetrating the magnetic transfer medium W using an NdFeB-based sintered magnet. gave.

Next, the surface of the master information carrier M on the magnetic layer side is opposed to the magnetic transfer surface A of the magnetic transfer medium W, and the magnetic transfer medium W is in contact with the master information carrier M with 98 mN. The layers were overlapped with each other by pressing force. Thereafter, an external magnetic field of 4 kOe was applied for 10 seconds from the side opposite to the transfer surface of the master information carrier M to write an information signal on the magnetic layer on one side of the magnetic transfer medium W.
Through the above steps, a magnetic recording medium in which an information signal was written was obtained.

<Evaluation of magnetic recording media>
A plurality of magnetic recording media were manufactured by repeatedly using one master information carrier M by the above method, and the reproduction characteristics such as pre-servo signals were evaluated for each of the obtained magnetic recording media as follows. .
That is, a read / write analyzer (model number: RWA1632; manufactured by GUZIK, USA) and a spin stand (model number) that can read a pre-servo signal recorded on a magnetic recording medium and position the magnetic head using the obtained signal. : S1701MP), and using a magnetic head using TuMR as the magnetic head, the S / N ratio (Singal to noise ratio) at the time of reading the pre-servo signal was measured. Then, when the S / N ratio is 16.0 dB or less, it is determined that the magnetic transfer is defective, and the number of times of magnetic transfer of one master information carrier M until the magnetic transfer failure occurs is defined as the number of times that magnetic transfer is possible. evaluated.

  As a result, in Example 1, 82,000 times of magnetic transfer was possible using one master information carrier M.

(Comparative Example 1)
In Comparative Example 1, a plurality of magnetic recording media were manufactured in the same manner as in Example 1 except that the deposit removal process was not performed.
As a result, in Comparative Example 1, 35,000 times of magnetic transfer was possible using one master information carrier M.

  DESCRIPTION OF SYMBOLS 31 ... Nonmagnetic substrate 32 ... Soft magnetic underlayer 32a ... Soft magnetic layer 32b ... Spacer layer 33 ... Orientation control layer 34 ... Perpendicular magnetic layer 35 ... Protective layer 36 ... Lubricating layer 38 ... Nonmagnetic underlayer 100 ... Ni base material 100a ... convex portion 100b ... concave portion 101 ... magnetic layer 200 ... nonmagnetic substrate 201 ... magnetic layer A ... magnetic transfer surface H ... deposit capturing plate M ... master information carrier W ... magnetic transfer medium G ... magnetic field generating means.

Claims (5)

Forming a magnetic transfer medium by forming a magnetic layer on the substrate;
An adhering matter removing step for removing adhering matter adhering to the magnetic transfer surface of the magnetic transfer medium;
The magnetic transfer medium is superposed on a master information carrier on which a transfer pattern corresponding to an information signal is formed, the magnetic transfer surface is opposed to the master information carrier, and an external magnetic field is applied from the master information carrier side. And a magnetic transfer step of writing an information signal to the magnetic layer of the magnetic transfer medium,
In the deposit removing step, the deposit capturing plate having a surface softer and less sticky than the magnetic transfer surface is bonded to the magnetic transfer surface, and the deposit adhered to the magnetic transfer surface is A bonding step of capturing by plastic deformation of the deposit capturing plate;
A method for producing a magnetic recording medium, comprising: a peeling step of removing the deposit together with the deposit capturing plate by peeling the deposit capturing plate from the magnetic transfer surface. Forming a magnetic transfer medium by forming a magnetic layer on the substrate;
An adhering matter removing step for removing adhering matter adhering to the magnetic transfer surface of the master information carrier on which a transfer pattern corresponding to the information signal is formed;
The magnetic transfer medium is superimposed on the master information carrier with the magnetic transfer surface facing the master information carrier, an external magnetic field is applied from the master information carrier side, and the magnetic layer of the magnetic transfer medium A magnetic transfer process for writing information signals to
In the deposit removing step, a deposit capturing plate having a surface softer and less sticky than the magnetic transfer surface is bonded to the magnetic transfer surface, and the deposit adhering to the magnetic transfer surface is captured. A laminating process for capturing by plastic deformation of the plate;
A method for producing a magnetic recording medium, comprising: a peeling step of removing the deposit together with the deposit capturing plate by peeling the deposit capturing plate from the magnetic transfer surface.   3. The method of manufacturing a magnetic recording medium according to claim 1, wherein the deposit capturing plate is made of a metal material.   4. The method of manufacturing a magnetic recording medium according to claim 3, wherein the deposit capturing plate is made of any one selected from the group consisting of aluminum, copper, gold, or an alloy thereof.   5. The method of manufacturing a magnetic recording medium according to claim 1, wherein the deposit removing step is performed in a reduced pressure environment.

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