JP2003173516A - Magnetic transfer master carrier - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve transfer signal quality by reducing recording loss, to improve durability by preventing the destruction of a master carrier pattern, and to suppress transfer failures when the master carrier is bonded to a slave medium, and a transfer magnetic field is applied to execute magnetic transfer. <P>SOLUTION: A master carrier 3 has recessed and projected patterns by a magnetic substance 32 corresponding to information transferred to a substrate 31, a round radius R of the plane shape of a top surface corner in a roughly rectangular projected pattern 32a of the recessed and projected patterns is set to be 1% to 47% of a track width W, and thus the destruction of the corner is prevented, and recording losses are reduced. <P>COPYRIGHT: (C)2003,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention
Master carrier for magnetic transfer carrying transfer information for gas transfer
It is about. [0002] A magnetic transfer method uses transfer information on the surface of a substrate.
The master with the irregular shape corresponding to the
-The surface of the carrier is a surface of a slave medium having a magnetic recording part.
In close contact with the surface, apply a magnetic field for transfer
-Corresponds to information carried on the carrier (eg servo signal)
Transfer and record the magnetization pattern on the magnetic recording part of the slave medium
Is. As this magnetic transfer method, for example, JP
Sho 63-183623, JP 10-40544 A
Disclosed in Japanese Patent Laid-Open No. 10-269666, etc.
ing. A master carrier used for magnetic transfer is a shim.
Photolithography on recon substrates, glass substrates, etc.
Sputtering, etching, etc. are applied to the magnetic material
It is composed of a concavo-convex pattern. In addition, lithog used in semiconductors, etc.
Raffy technology or optical disc stamper creation
Applying stamper making technology used for magnetic transfer
It is contemplated to create a master carrier. To improve transfer quality in the magnetic transfer
In order to achieve this, the gap between the master carrier and the slave medium
Close contact is an important issue. In other words, poor adhesion
If there is an area where magnetic transfer does not occur, magnetic transfer
If this does not occur, the magnetic information transferred to the slave medium will be
Signal loss occurs, signal quality deteriorates, and recorded signals are not supported.
In the case of a robot signal, the tracking function cannot be obtained sufficiently
However, there is a problem that reliability is lowered. [0006] In addition, the applicant of the present application, Japanese Patent Application No. 11-11
In 7800, the magnetization of the magnetic recording medium is initially
DC magnetized, then magnetic recording medium and soft magnetic layer pattern
The master magnetic carrier with
Magnetic transfer that enables better transfer
A method has been proposed. [0007] By the way, as described above.
With the master carrier, the irregularities corresponding to the transfer information on the substrate
When the pattern is made of magnetic material,
It was found that the surface shape has an influence on the transfer characteristics. The details will be shown in the experimental examples described later.
To create multiple types of master carriers.
Magnetic transfer to a slave medium using a carrier, and the transfer
After confirming the signal quality, the master carrier preparation conditions
Depending on the situation, the signal quality is not affected by magnetic transfer.
To the conventional method of recording signals directly to slave media
There were cases where the level was lower than that. At that time, it is formed on the master carrier.
When the shape of the concavo-convex pattern was confirmed,
It can be seen that the planar shape of the top corner is greatly affected
It was. For example, the uneven pattern of the transfer information corresponding to the servo signal
In the case of slave disk media,
A rectangular or square convex part that is long in the width direction (radial direction)
It forms a turn, but the four corners are chamfered.
If it is formed at an acute angle without squeezing, it will keep in close contact with the slave medium.
When the corners are turned over, the corners are missing, causing dust.
It has been clarified that it causes deterioration of transcription signal quality. From the above points, the corners of the convex pattern are chamfered.
It is necessary to do this, but when chamfering in an arc shape,
The size of the rounded radius R also affects the quality of the transferred signal.
It was found that In other words, various rounded corners
A star carrier was prepared, and its radius R was used as a parameter.
As a result of experiment and simulation, radius R of rounded corners
When the size becomes larger, the master carrier and the slave medium are in close contact with each other
When magnetic transfer is performed, the transfer with rounded corners is applied.
Magnetizing the slave medium by causing a recording loss in the copying magnetic field
Pattern formation is incomplete and clear signals cannot be recorded.
And elucidated. Reduce the rounded radius R to approach a rectangular shape
The transfer signal quality is improved because the recording loss is reduced.
However, this radius R is reduced to sharpen the four corners of the convex pattern.
Performs multiple magnetic transfers using a master carrier
And signal quality declined. This is the pattern
The corners are damaged, and the broken pieces remain on the pattern.
It turns out that the recording signal is missing due to a defect.
It was. In particular, the recording capacity of the slave medium increases.
And the uneven pattern formed on the master carrier is also finer
Prevents damage to the corners of the convex pattern and reduces recording loss
Ensure compatibility of conflicting requirements and improve reliability
I have to. The present invention has been made in view of these problems.
So, the master carrier and slave medium are in close contact for transfer
To reduce recording loss when performing magnetic transfer by applying a magnetic field
Improves transfer signal quality and breaks the pattern of the master carrier
Magnet with improved durability and transfer defects
The object is to provide a master carrier for air transfer
It is. In the magnetic transfer as described above,
Hold the slave media from one side by a flat master carrier.
Or in order to make it come in close contact with both sides.
Dust must be removed at a high level. Adhesion
If there is dust in the area, magnetic transfer can be performed stably.
As well as damage to the master carrier and the slave medium itself.
This is because it may cause scratches. In magnetic transfer, a master carrier and a thread are used.
Apply relatively strong pressure to the probe medium and adhere to the entire surface.
For this reason, it is necessary to repeat the magnetic transfer many times to increase the number of contact
Then, by this process, the soft magnetic layer created on the substrate becomes
The transfer signal quality is low due to peeling off and interposing it in the contact area.
Factors that degrade the durability of the master carrier
It has become. Analysis of the peeled portion of the soft magnetic layer
As a result, when the master carrier and the slave medium are in close contact
In addition, the deformation of the master carrier is large, especially the amount of deformation is large.
It was found that the soft magnetic layer was peeled off at the location. Furthermore, in magnetic transfer, the master carrier and
A relatively strong pressure is applied to the reve medium, and the entire surface is in close contact.
After applying the magnetic field for transfer with
Separate slave media, master carrier and slave media
The air is pumped and separated from the outer periphery of the body, and the master
Remove the carrier and slave medium by vacuum suction.
Repeated many times of magnetic transfer
The magnetic properties created on the substrate by these processes.
Layer wear, wear, delamination, missing, edge change, etc.
As a result, the shape of the transferred pattern changes and the transfer signal quality
Reduced or generated wear powder or the like is interposed
Transfer signal quality deteriorates and the master carrier
There was a problem that the durability of the deteriorated. Specifically, the protrusion of the substrate of the master carrier.
The magnetic layer formed on the part is thin due to wear and abrasion.
Or the edge of the magnetic layer is missing
Magnetic layer width narrows, top surface magnetic layer and slave medium
And dents occur in the magnetic layer due to foreign matter in the crimped part.
After cutting, there was a poor adhesion with the slave medium after that
Repeatedly perform stable magnetic transfer
It becomes difficult. The present invention has been made in view of these problems.
So, the master carrier and slave medium are in close contact for transfer
Wear and wear of the magnetic layer during magnetic transfer by applying a magnetic field
Durability, peeling, missing, edge change etc.
Master carrier for magnetic transfer with improved and reduced transfer defects
Is intended to provide. Also, the magnetic transfer method as described above is a conventional method.
Compared with servo write with the magnetic head of
Effect of demagnetizing field on magnetic recording medium due to field application
Is small. However, in particular, Japanese Patent Application No. 11-1178
As in the magnetic transfer method described in No. 00, a magnetic recording medium in advance
When applying a transfer magnetic field after initial DC magnetization of
Takes into account the effects of demagnetizing fields on the magnetic layer of magnetic recording media
There is a need to. For longitudinally magnetized recording media, the recording capacity
There is a tendency for the distance between magnetization transition regions to become shorter as the quantity increases.
Yes, for magnetic recording media with a short magnetization transition region interval.
In particular, during magnetic transfer, magnetic transfer
The pattern of the master carrier for copying and recorded accordingly
Deviation occurs in the magnetic pattern on the magnetic recording medium
Problems can occur. That is, the desired magnetic pattern
Cannot be recorded on the magnetic recording medium accurately.
The transition region may shift from the original position. Such deviation of the magnetization transition location, ie,
The deviation of the magnetization pattern from its original position is
Greatly affecting the accuracy of recording and playback of recording media
Become. Especially when the information to be transferred is a servo signal
In some cases, the tracking performance will decrease and the reliability will decrease.
There are problems such as. In view of the above circumstances, the present invention provides a magnetic transfer smell.
Record the desired magnetization pattern on the magnetic recording medium with high accuracy.
A master carrier for magnetic transfer that can be provided
aimed to. The magnetic transfer mass of the present invention
The carrier is uneven with magnetic material corresponding to the information to be transferred.
A magnetic transfer master carrier having a pattern,
Top surface angle in a substantially rectangular convex pattern formed on the plate
The radius R of the roundness of the planar shape of the part is set to the track width W,
1% to 47% (preferably 45% or less)
It is characterized by this. The master carrier has irregularities according to information.
Metal is deposited on the formed master by a metal deposition method such as electroforming.
Concave and convex pattern formed using a peeling stamper method
It is desirable that the substrate be formed of a substrate having The main component of this board
It is preferable that the content is Ni,
The magnetic material that covers the surface and forms the convex pattern has a coercive force.
Soft magnetism with Hcm of 48kA / m (≒ 600Oe) or less
The body is preferred. In addition, the master carrier for magnetic transfer of the present invention
The magnetic transfer method used corresponds to the information transferred onto the substrate.
Having a concavo-convex pattern made of a magnetic material, the concavo-convex pattern
Planar shape of the top corner of the substantially rectangular convex pattern
The radius R of the circle is 1% or more of the track width W, 4
7% or less of the master carrier for magnetic transfer and receiving the transfer
Tightly transfer to a slave medium with a magnetic recording section
Applying a magnetic field to the concave / convex pattern of the master carrier.
To transfer the corresponding magnetization pattern to the slave medium
It is. When performing magnetic transfer, the magnetic field of the slave medium is used.
In the track direction for in-plane recording and perpendicular recording
Then, the initial direct current magnetization in the vertical direction,
The tiger is placed in close contact with the body and has a direction opposite to the initial DC magnetization direction.
Magnetic transfer by applying a transfer magnetic field in the
It is preferable to perform copying. The initial magnetization of the slave medium is the slave medium
Magnetic field strength distribution with a magnetic field strength part greater than the coercive force Hcs
To generate a magnetic field and magnetize the entire slave medium in a predetermined direction.
To do. The magnetic field for transfer is applied by the master for magnetic transfer.
A state in which the carrier and the slave medium with initial DC magnetization are in close contact with each other
To do. The concave / convex pattern of the substrate has a magnetization pattern.
Positive pattern or negative pattern for the turn
In other words, even if the unevenness is reversed, the magnetic transfer process
The initial magnetization and the direction of the magnetic field for transfer are positive and negative.
If reversed, the same magnetization pattern can be obtained.
Yes. A master carrier is provided on one side of the slave medium.
For single-sided sequential transfer with close contact, and for slave media
Simultaneous transfer of both sides with the master carrier in close contact with both sides
There is a case to do. At that time, one side of the slave medium
Is a master carrier on both sides, one side or both sides
A magnetic field generating means is disposed on the surface to apply a transfer magnetic field. magnetic field
The generating means generates a magnetic field parallel to the track direction for in-plane recording.
For perpendicular recording, a magnetic field is generated perpendicular to the slave surface.
If the magnetic field is part of the slave medium,
Move the magnetic carrier with the master carrier in close contact
Then, the magnetization pattern is transferred to the entire surface of the slave medium. Magnetism
As the field generation means, an electromagnet device or a permanent magnet device is used.
used. Furthermore, the magnetic transfer master carrier of the present invention.
The slave medium magnetically transferred by the
It has a concave / convex pattern made of magnetic material corresponding to the servo signal
In the substantially rectangular convex pattern of the concave / convex pattern
The radius R of the planar shape of the top corner is the track width W
On the other hand, the master for magnetic transfer which is 1% or more and 47% or less
The master is in close contact with the carrier and a transfer magnetic field is applied.
Servo signal magnetization pattern corresponding to the uneven pattern of the carrier
And a magnetic recording portion to which the toner is transferred. Sule
Media such as hard disks and flexible disks
A disc-shaped magnetic recording medium is suitable. Further, the master carrier for magnetic transfer of the present invention
Magnetics with a soft magnetic layer on a pattern formed on a substrate
A master carrier for transfer, wherein the Young's modulus (E
1) Ratio e (e = E) between the Young's modulus (E2) of the soft magnetic layer
1 / E2) is in the range of 0.3 <e <1.3
It is desirable to have a characteristic. That is, as described above, the change of the master carrier
The soft magnetic layer is peeled off depending on the shape.
Relationship between elastic properties of substrate with turn and soft magnetic layer
The substrate and soft magnetic layer
As a result of grasping the relationship of delamination using the
Deriving the Young's modulus relationship between the substrate and soft magnetic layer as described above
I put it out. Also, the master carrier for magnetic transfer of the present invention
Transcribes information to the slave medium receiving the transcription
Magnetic transfer with a patterned magnetic layer on the substrate
Master carrier, the magnetic layer transferring information
On the convex surface of the substrate formed in a pattern corresponding to
Protruding magnetic layer provided and concave provided in the concave portion of the substrate
A boundary between the convex magnetic layer and the concave magnetic layer.
The boundary portion is provided with a reinforcing edge erected on the convex portion of the substrate.
It is desirable that it is characterized by being placed
Yes. At this time, the magnetic transfer master carrier
Create the shape of the convex, concave and reinforcing edges of the substrate
For example by multi-step exposure and etching
After forming a magnetic layer on this substrate, the surface is polished
Process and remove the extra magnetic layer deposited on the reinforcing edge
You can do that. The magnetic layer is formed by vacuum evaporation of soft magnetic material.
Deposition, sputtering, ion plating, etc.
It is preferable to carry out by a vacuum film forming means. Furthermore, the magnetic transfer master carrier of the present invention.
For transferring information to the magnetic layer of the magnetic recording medium
Formed from a plurality of convex portions having a magnetic layer on the surface.
A magnetic transfer master carrier with a pattern,
The pattern is magnetically transferred to the magnetic recording medium by magnetic transfer.
Demagnetizing field correction is applied to the magnetization pattern transferred to the conductive layer.
It is characterized by being defined
It is desirable. That is, the master for magnetic transfer according to the present invention.
The pattern of the body is the width of each convex part and each
The width between the protrusions is transferred to the magnetic recording medium by this pattern.
The width of each small area of the magnetic pattern to be
In other words, it is determined by correcting the demagnetizing field component in advance.
It is a feature. Therefore, the magnetic transfer of the present invention
The width of each part of the pattern of the master carrier for the magnetic recording medium
To the width of each corresponding part of the desired magnetic pattern to be transferred to
In contrast, the dimensional relationship is not 1: 1. Magnetic recording
Information transferred to the magnetic layer of the recording medium includes servo signals,
ROM-like signals and the like can be mentioned. According to the master carrier of the present invention as described above,
The radius R of the top face corner roundness of the convex pattern is the track width.
Recording loss by specifying 1% to 47% with respect to W
Transfer signal quality improvement by reducing the
Improves durability by preventing damage to the screen and suppresses transfer defects
I was able to win. That is, the radius R is 47% of the track width W.
With the following, the master carrier and the slave medium
Applied magnetic field for magnetic transfer with close contact
Increases the recording loss that occurs at the rounded corners.
Transfer and record a bright magnetization pattern to normal transfer signal quality
Can be above the level of writing with a magnetic head
The Also, the radius R should be 1% or more of the track width W
Prevents the corners from becoming excessively sharp and close to the slave medium.
Even if the magnetic transfer is repeated multiple times, the corners are damaged.
Due to poor transfer with broken pieces.
Recording signal loss does not occur, and deterioration of transfer signal quality is suppressed.
And increase the durability of the master carrier and transfer times
Can be increased. Further, the magnetic field using the master carrier of the present invention.
According to the gas transfer method, an accurate and high transfer signal quality
Turn transfer is possible and the master carrier is highly durable
In addition, work efficiency is improved by reducing the number of master carrier replacements.
Magnetic transfer can be performed. In addition, the master carrier of the present invention provides magnetic properties.
Transferred slave media can be used to accurately transfer signals with high signal quality.
Slave media with a magnetized pattern can be provided at low cost
Yes. In the master carrier of the present invention, the pattern
The Young's modulus (E1) of the substrate on which the wire is formed and the substrate
Ratio of Young's modulus (E2) of the soft magnetic layer formed on the pattern
e (e = E1 / E2) in the range of 0.3 <e <1.3
If specified, the master carrier and the slave can be
The medium is repeatedly adhered to the entire surface with strong pressure, and the master
Even in areas where body deformation is large, soft magnetic layer peeling is significantly reduced
Recording signal missing due to transfer failure with peeled pieces
Is not generated, and the deterioration of the transfer signal quality can be suppressed,
The durability of the master carrier can be increased and the number of transfers can be increased. In the master carrier according to the present invention,
Convex magnets formed in a pattern corresponding to the information to be transferred
On the convex part of the substrate at the boundary between the magnetic layer and the concave magnetic layer
If the reinforced edge is arranged, the slave medium
The convex magnetic layer that is repeatedly in close contact with the peripheral edge is the reinforcing edge
Reinforced by the wear, wear, delamination, and chipping of the magnetic layer.
Drop and edge change can be suppressed, and the durability of the master carrier
Stable magnetism is prevented by improving transferability and preventing transfer defects.
The air transfer can be repeated and the reliability can be improved. Furthermore, the magnetic transfer master carrier of the present invention.
Has a pattern that takes into account the effects of demagnetizing fields in advance.
Magnetic transfer using this magnetic transfer master carrier.
When copying, the desired magnetization parameter is recorded on the magnetic recording medium.
Turns can be recorded with high accuracy. Magnetic recording medium
The desired magnetization pattern is recorded on the top with high accuracy.
To accurately reproduce the information based on the magnetization pattern.
Especially when the information is a servo signal
The tracking accuracy is improved. DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail below.
Explained. FIG. 1 shows an embodiment of the present invention.
It is a figure which shows an example of the magnetic transfer method using a master carrier.
is there. FIG. 2 is a schematic diagram of the convex pattern of the master carrier.
The The form shown in FIG. 1 is an in-plane recording method. Ma
Each figure is a schematic diagram, and the dimensions of each part are different from the actual ratio.
Shown in rate. The outline of the magnetic transfer method by in-plane recording is as follows.
It ’s like that. First, as shown in Fig. 1 (a)
Applying an initial static magnetic field Hin to the slave medium 2 in the track direction
In this way, initial magnetization (DC demagnetization) is performed in advance. after that,
As shown in FIG. 1B, the slave of this slave medium 2
Surface (magnetic recording part) and the fineness of the substrate 31 of the master carrier 3
The concavo-convex pattern is covered with the soft magnetic layer 32 (magnetic material).
Adhering to the top surface of the convex pattern 32a of the information carrying surface
The initial magnetic field Hin in the track direction of the slave medium 2
Magnetic transfer is performed by applying a magnetic field for transfer Hdu in the opposite direction
Yeah. The magnetic field for transfer Hdu is the soft magnetic layer 3 having the convex pattern 32a.
2 so that the magnetization of this part is not reversed.
As a result of the reversal of the magnetic field of the portion, as shown in FIG.
The master side of the slave surface (track) of the rave medium 2
Close contact convex pattern 3 of the soft magnetic layer 32 on the information carrying surface of the body 3
Magnetization pattern according to the formation pattern of 2a and recess space
Is transferred and recorded. The master carrier 3 is formed in a disk shape,
A fine magnetic layer 32 corresponding to the servo signal is provided on one side.
It has a transfer information carrying surface on which a fine uneven pattern is formed.
The opposite surface is held by the contact means (not shown)
Is in close contact with the medium 2. As shown, slave medium 2
The master carrier 3 is brought into close contact with one side of the sheet and one-sided sequential transfer is performed.
And on both sides of the slave medium 2
There are cases in which the body 3 is brought into close contact and simultaneous double-sided transfer is performed. As shown in FIG. 2, in the master carrier 3
The planar shape of the top surface of the convex pattern 32a is substantially rectangular.
The corner is chamfered in an arc shape, and the radius of roundness of this corner
R is 1% to 47% of track width W (preferred
Or 45% or less). Sir
In the case of signal, the track width W is about 0.1 to 2 μm.
Since the track width W is 0.1 μm
The radius R is 1 to 47 nm and the track width W is 2 μm.
In this case, the radius R is 20 to 940 nm.
The radius R is 5 nm to 47 nm (preferably 5 to 45 n).
It is desirable to form in the range of m). Less than 5nm
The part is easily damaged, and if it exceeds 47 nm, the recording loss
growing. Although not shown, the actual servo signal
Is a convex pattern shifted by half the pitch of the track pitch
The radius R of the roundness of the convex pattern is the same as above.
It is prescribed as follows. It should be noted that the concave of the substrate 31 of the master carrier 3
Negative having a convex and concave shape opposite to the positive pattern in FIG.
Even in the case of a pattern, the direction of the initial magnetic field Hin and
By making the direction of the transfer magnetic field Hdu opposite to the above
The same magnetization pattern can be transferred and recorded. The substrate 31 is made of a ferromagnetic material such as Ni.
In this case, magnetic transfer is possible only with this substrate 31 and a soft magnetic layer.
32 does not need to be coated, but a soft magnetic layer with good transfer characteristics
By providing 32, better magnetic transfer can be performed. substrate
When 31 is a non-magnetic material, it is necessary to provide the soft magnetic layer 32.
It is important. It should be noted that the diamond layer is placed on the soft magnetic layer 32.
It is preferable to provide a protective film such as squid carbon (DLC)
Alternatively, a lubricant layer may be provided. Also as a protective film 5
The presence of a 30 nm DLC film and a lubricant layer
preferable. Further, Si or the like is interposed between the soft magnetic layer 32 and the protective film.
An adhesion reinforcing layer may be provided. Lubricant, slave medium
2 due to friction when correcting the deviation caused in the contact process with
Improve durability deterioration such as the occurrence of scratches. The substrate 31 of the master carrier 3 is a nickel substrate.
Kel, silicon, quartz plate, glass, aluminum, composite
Use gold, ceramics, synthetic resin, etc. Uneven pattern
The formation of the film is performed by a stamper method or the like. The stamper method uses a glass plate with a smooth surface.
Photoresist by spin coating on (or quartz plate)
Servo signal while rotating this glass plate
A laser beam (or electron beam) modulated according to
Irradiate and apply a predetermined pattern on the entire surface of the photoresist, for example
Servo signal extending radially from the center of rotation to each track
The pattern corresponding to each frame on the circumference
Expose in minutes. Then, develop the photoresist,
The exposed part is removed and it has a concavo-convex shape by photoresist.
Get the master. Next, based on the uneven pattern on the surface of the master
In addition, the surface is plated (electroformed) to form a positive uneven pattern.
A Ni substrate having a film is prepared and peeled off from the master. This
Use the substrate as a master carrier as it is, or
Cover the turn with a soft magnetic layer and protective film as necessary.
A star carrier is used. Further, the original master is plated to give a second original.
Create a board and perform plating using this second master,
You may create the board | substrate which has a negative uneven | corrugated pattern. The
In addition, plating the second master or pressing the resin liquid
Make a third master by curing and plate on the third master
To create a substrate with a positive concavo-convex pattern
Good. On the other hand, the glass plate is made of a photoresist.
After forming the pattern to be etched, holes are formed in the glass plate by etching.
To obtain a master plate from which the photoresist has been removed.
A substrate may be formed in the same manner as described above. The material of the substrate 31 made of metal is Ni.
Alternatively, an Ni alloy can be used to make this substrate.
The plating to be formed is electroless plating, electroforming, sputtering.
Various metal film formation methods including ion plating and ion plating
Applicable. Depth of concavo-convex pattern on substrate 31 (projection height
Is preferably in the range of 80 nm to 800 nm, more
Preferably it is 100 nm-600 nm. The soft magnetic layer 32 is formed by using a magnetic material.
Air evaporation method, sputtering method, ion plating method
The film is formed by a vacuum film forming means such as a plating method or the like. That
Magnetic materials include Co, Co alloys (CoNi, CoN
iZr, CoNbTaZr, etc.), Fe, Fe alloy (Fe
Co, FeCoNi, FeNiMo, FeAlSi, F
eAl, FeTaN), Ni, Ni alloy (NiFe)
Can be used. Particularly preferably, FeCo, FeC
oNi. The thickness of the soft magnetic layer 32 is 50 nm to 50 nm.
The range of 0 nm is preferable, more preferably 100 nm
~ 400 nm. A resin substrate was prepared using the master,
A soft magnetic layer may be provided on the surface to serve as a master carrier. Tree
The resin material for the fat substrate includes polycarbonate and polymer.
Acrylic resin such as chill methacrylate, polyvinyl chloride
Vinyl chloride resin such as rubble / vinyl chloride copolymer, Epoxy
Resin, amorphous polyolefin and polyester
Can be used. Moisture resistance, dimensional stability and value
Polycarbonate is preferred from the standpoint of rating. For molded products
If there is burr, use varnish or polish
Remove. UV curable resin, electron beam curable resin, etc.
Using spin coating and bar coating on the master
You may make it. The height of the pattern protrusion on the resin substrate is 50
Preferably in the range of ~ 1000 nm, more preferably 1
It is the range of 00-500 nm. On the fine pattern on the surface of the resin substrate
A soft carrier is coated to obtain a master carrier. Formation of soft magnetic layer
Magnetic material is vacuum deposition, sputtering, ion
By vacuum deposition means such as plating, plating
A film is formed. Also in the case of the vertical recording method, the above-mentioned in-plane recording and
An almost similar master carrier 3 is used, and the substrate 3
A concavo-convex pattern is formed on 1, and the convex pattern 32
The top surface of a is formed of a soft magnetic layer 32 (magnetic material) and is substantially planar.
Planar shape of the top corner of the rectangular convex pattern 32a
The radius R of the round shape is 1% or more with respect to the track width W,
It is specified to be 47% or less. In the case of this perpendicular recording, the slave medium 2
The initial DC magnetization in one of the vertical directions is
The initial direct current magnetization direction is in close contact with the master carrier 3
Magnetic transfer by applying a magnetic field for transfer in the vertical direction, approximately opposite to
This transfer magnetic field is applied to the master carrier 3.
A convex portion is sucked into the soft magnetic layer 32 of the convex pattern 32a.
The perpendicular magnetization of the part corresponding to the pattern 32a is reversed and the concave
Magnetization pattern corresponding to the convex pattern is in the slave medium 2
Can record. The slave medium 2 is magnetic on both sides or one side.
Hard disk with recording area (magnetic layer), high density
Disc-shaped magnetic recording media such as flexible disks are used
The magnetic recording part is a coated magnetic recording layer or metal
It is composed of a thin film magnetic recording layer. Metal thin film type magnetic recording layer
As the magnetic material, Co, Co alloy (CoPtCr,
CoCr, CoPtCrTa, CoPtCrNbTa,
CoCrB, CoNi, etc.), Fe, Fe alloy (FeC
o, FePt, FeCoNi).
This is due to the high magnetic flux density and the same direction as the magnetic field application direction.
(In-plane direction for in-plane recording, vertical direction for perpendicular recording)
Because it has air anisotropy, clear transfer is possible.
preferable. And the necessary magnetism under the magnetic material (support side)
It is necessary to provide a non-magnetic underlayer to provide air anisotropy
preferable. Matching the crystal structure and lattice constant to the magnetic layer
is necessary. For that purpose, Cr, CrTi, CoCr,
CrTa, CrMo, NiAl, Ru or the like is used. The slave medium 2 is a master carrier 3.
Before it is in close contact with the glide head, abrasive body, etc.
Cleanin that removes minute protrusions or dust on the surface
Processing is performed as necessary. Magnetic field for applying initial magnetic field and transfer magnetic field
In the case of in-plane recording, the generation means is, for example, a slave medium.
Coil on core with gap extending radially in body 2
Ring-type electromagnet device wrapped around
It is emitted in the same direction at the top and bottom in parallel with the track direction.
Apply the generated magnetic field for transfer. When applying a magnetic field,
While rotating the adhesion body of the probe medium 2 and the master carrier 3
A magnetic field for transfer is applied by the magnetic field generating means. Magnetic field generation
The means may be provided to rotate. Magnetic field
The generating means may be arranged only on one side,
The magnet device may be arranged on both sides or one side. The magnetic field generating means in the case of perpendicular recording is
Use different electromagnets or permanent magnets as slave medium 2 and master
-Placed above and below the carrier 3 and the magnetic field in the vertical direction
Generate and apply. It applies a magnetic field partially
Moves the close contact between the slave medium 2 and the master carrier 3
Or move the magnetic field to perform magnetic transfer on the entire surface. Here, the master in the above embodiment
Example of carrier and comparative example are shown, and pattern of master carrier
Experimental results in which the radius R of the rounded shape is in the above range
Explain the results. Master carrier and slave used in the experiment
The medium and magnetic transfer method are as follows. <Preparation of master carrier> Glass having a smooth surface
Photoresist (resist for electron beam writing)
G) is applied by spin coating, and the glass plate is rotated.
The exposure was performed by irradiating with an electron beam. Then
Photoresist is developed and the exposed area is removed to create the master
After that, it is plated and peeled off from the master to make a Ni substrate
did. The uneven pattern of the Ni substrate is radial from the center of the disk.
1. A width of 0.3 μm and a distance of 2 to 20 mm in the direction.
Radial line with 5 μm and groove depth of 0.2 μm, between lines
At a distance of 0.5 μm at the innermost circumferential position in the radial direction of 20 mm
is there. On this Ni substrate, Fe having a thickness of 200 nm is formed.
A Co 30 at% layer (soft magnetic layer) was formed. Ar Spat
Ta pressure is 1.5 × 10 ^-Four Pa (1.08 mTorr)
Input power is 2.80 W / cm ² It was. The track width W of the pattern, half rounded corners
The diameter R was changed variously, and in Example 1, W = 0.3 μm, R
= 5 nm (R / W = 1.7%), Example 2, R = 20
nm (R / W = 6.7%), W = 0.1 μ in Example 3
m, R = 45 nm (R / W = 45%), in Comparative Example 1, W =
0.3 μm, R = 2 nm (R / W = 0.67%), comparison
In Example 2, W = 0.1 μm, R = 48 nm (R / W = 48
%) Master carrier sample. The method for measuring the radius R of the roundness is as follows:
Observe surface of master carrier after preparation with roughness measurement SEM
The pattern shape was observed. From the observation results
The radius R of the roundness of the turn was calculated. <Preparation of slave medium> Vacuum film forming apparatus (turf
(Ura Mechatronics: S-50S sputtering equipment)
1.33 × 10 at room temperature ^-Five Pa (10 ^-7 Torr)
After depressurization, argon was introduced and 0.4 Pa (3 × 1
0 ^-3 Torr), the glass plate was heated to 200 ° C.
CrTi 60nm, CoCrPt 25nm, magnetic flux density
Degree Ms: 5.7T (4500 Gauss), coercive force Hcs: 1
99-kA / m (2500 Oe) 3.5-inch disk
Create a magnetic recording medium (hard disk) and slave
Used as medium. <Magnetic transfer test method> The peak magnetic field strength is low.
On the surface of the slave medium, the slave medium coercive force Hcs
To be twice 398 kA / m (5000 Oe),
A ring-type head electromagnet is placed, which is the first slave medium 2
Phase DC magnetization was performed. Next, the initial DC magnetized slave medium
The body and master carrier are brought into close contact with each other so that the peak magnetic field strength
207 kA / m (2600 O at the surface of the reve medium
e) Adjust the current of the ring-type head electromagnet so that
And place a transfer magnetic field in the direction opposite to the initial DC magnetization.
In addition, magnetic transfer was performed. Master carrier and slave
The adhesion of the medium is from above the aluminum plate with the rubber plate in between.
Pressurized. <Signal quality evaluation method> Electromagnetic conversion characteristic measuring device
Device (SS-60 manufactured by Kyodo Electronics Co., Ltd.)
The copying signal was evaluated. The head has a playback head gap.
: 0.19 μm, playback track width: 2.0 μm, recording
Head gap: 0.4 μm, recording track width: 2.6
An MR head that is μm was used. Specified read signal
Frequency decomposition with a Cutroanalyzer and the peak of the primary signal
The difference (C / N) between intensity C and nearby noise N was measured. Conventional
As a method, a signal is recorded and reproduced with the same head, and the calculated C /
N value is 0 dB, and evaluation is performed with relative value (ΔC / N)
It was. Eccentricity when set in a slave medium device
Is large and cannot evaluate all signals over one lap
Therefore, local evaluation is performed using the lead gate function.
It was. If the track width is narrower than the lead width of the head
Calibrated (standardized) the C / N value with the track width. the above
Relative value (ΔC / N) is smaller than −3.0 dB (minor
The signal strength is small and transfer defects are poor.
Since it becomes a state, if it is more than this value, it is good (○), in the following
If there was, it evaluated as a defect (x). The results are shown in Table 1.
The <Signal loss / contact evaluation method> Same master
Repeat the magnetic transfer with the carrier, and the magnetic transfer at the 1000th time.
The slave medium is magnetic developer (Sigma High Chemical Co., Ltd.)
Manufactured: Sigma marker Q) diluted 10 times, slave medium
The fluctuation amount of the transfer signal edge that is dropped, dried and developed on the
evaluated. Slate at 50x magnification with a differential interference microscope
Randomly observing 100 missing fields on signal media
To do. If there are 5 or less signal gaps in this 100 field of view
Good (○), acceptable for 6-9 locations (△), more than 10 locations
If there was, it evaluated as a defect (x). The results are shown in Table 1.
The [Table 1] As can be seen from Table 1, the radius R of rounded corners is
In Comparative Example 1 of 2 nm (R / W = 0.67%), signal quality
Is good, but the convex part after 1000 times of magnetic transfer
Numerous signal loss occurs due to damage to the corners of the pattern.
It was. In contrast, the rounded radius R is 5 nm to 45 nm.
In Examples 1 to 3 (R / W = 1.7% to 45%),
The quality of the item is slightly inferior to that of Comparative Example 1, but in a good range.
It is a good result with few issues and corner breakage occurs.
Not. 48 nm (R
In Comparative Example 2 where / W = 48%)
Is not a problem, but the signal quality decreases due to an increase in recording loss.
The transfer is defective. As a result, the roundness is
Radius R is 5 to 47 nm, ratio of track width W to R /
Confirm that the range of 1 to 47% is good as W
It was. In another embodiment of the present invention, FIG.
In the master carrier 3 shown in FIG.
Young's modulus (E1) of the substrate 31 and the pattern of the substrate 31
The Young's modulus (E2) of the soft magnetic layer 32 formed on the wire
The ratio e (e = E1 / E2) is in the range of 0.3 <e <1.3
It is stipulated in. The substrate 31 and the soft magnetic layer 32 of the master carrier 3
By setting the ratio e of Young's modulus in the above range,
Master carrier 3 and slave medium 2 are strong according to magnetic transfer
Master carrier 3 when it is repeatedly adhered to the entire surface with high pressure
Even in a portion where the deformation of the substrate 31 is large, the substrate 31 and the soft magnetic layer 32
The deformation does not deviate greatly, and the soft magnetic layer 32 is peeled off.
Can be prevented, does not cause dust generation, and the transfer signal quality is ensured.
And the durability of the master carrier 3 is increased. Here, the master in the above embodiment
Implementation by changing the ratio e of Young's modulus between the carrier substrate and the magnetic layer
An example and experimental results with this ratio e in the above range
Will be explained. Perform the experiment in the same way as above, and evaluate signal loss.
The results are shown in Table 2. In the first to third embodiments, the substrate is made of Ni, magnetic
The ratio e of the Young's modulus is the FeCo 30 at% layer.
The signal omission evaluation was good. Fruit
The master carrier of Example 4 is the same as that of Example 1, and
The board was changed to Constantan, and the Young's modulus
The ratio e is 1.25. The master carrier of Example 5 is
The substrate is the same as in Example 1, and the substrate is made of tungsten carbide.
The ratio of Young's modulus e is 0.38.
The The master carrier of Example 6 is the same as that of Example 1
The substrate is changed to Cu, and the Young's modulus ratio e
Is 1.53. The master carrier of Example 7 is
Same as 1, change the substrate to polycarbonate
The Young's modulus ratio e is 0.19. Of Table 2
As a result, Examples 4 and 5 in which the ratio e of Young's modulus is within the above range.
The signal omission evaluation is good, and the results are slightly out of the above range.
In Examples 6 and 7, signal loss increased and the evaluation was acceptable.
ing. [Table 2] Hereinafter, still another embodiment of the present invention will be described in detail.
Explain in detail. FIG. 3 shows a master according to one embodiment.
It is sectional drawing which shows the principal part of a support | carrier typically. Figure 4 is the master
-It is sectional drawing which shows the example of a preparation process of a support | carrier. Here, the base of magnetic transfer to which the present invention is applied.
One mode of this step will be described with reference to FIG. This example
This is due to internal records. First, magnetism that undergoes magnetic transfer
A slave medium 22 having a recording layer is shown in FIG.
The magnetic layer 25 covers the fine uneven pattern of the substrate 24.
And has a concavo-convex pattern by the magnetic layer 25
A master carrier 23 is prepared. And first, FIG.
As shown in (a), the initial static magnetic field Hin is applied to the slave medium 22.
Is applied in one direction in the track direction and the initial magnetization (DC
Degauss). Then, as shown in FIG.
Magnetic recording surface of the medium 22 and magnetic layer of the master carrier 23
25 is closely attached to the convex pattern, and the slave medium 2
Transfer magnetic field in the direction opposite to the initial magnetic field Hin in the track direction 2
Magnetic transfer is performed by applying the field Hdu. Magnetic field for transfer Hdu is magnetic
Sucked into the convex pattern by the conductive layer 25,
As a result of the magnetization of other parts not reversing,
As shown in FIG. 5C, the track of the slave medium 22
Depending on the concave / convex pattern of the magnetic layer 25 of the master carrier 23
The magnetized pattern is transferred and recorded. In addition, perpendicular recording system
Also in the concavo-convex pattern by the magnetic layer substantially similar to the above
By using a master carrier with a slave
Magnetic transfer can be performed on the medium. As shown in FIG. 3, the magnetic transfer master
The body 40 includes a convex portion 41a, a concave portion 41b, and a reinforcing edge portion 41c.
Provided with a substrate 41 having a fine uneven shape formed by
The pattern corresponding to the information to be transferred to the surface portion on the substrate 41
Convex magnetic layer 42a provided on convex part 41a.
And the concave magnetic layer 42b provided in the concave portion 41b.
A magnetic layer 42 is provided. And said convex part
At the boundary between the magnetic layer 42a and the concave magnetic layer 42b, the base
Reinforcing edge 41c erected on the convex portion 41a of the plate 41 is disposed
Has been. In the illustrated case, the reinforcing edge portion 41c is
Same as the convex magnetic layer 42a on both sides of the convex portion 41a of the substrate 41.
It is formed in a narrow protrusion shape at the same height. This reinforcing edge
41c is formed on the upper portion of the convex portion 41a of the substrate 24.
So that the convex magnetic layer 42a is embedded in the concave portion.
Is formed. The master carrier 40 as described above is
As shown in FIG. 4 (a), convex portions 41a and concave portions 41b are formed on the surface.
And a base having a fine concavo-convex shape formed by the reinforcing edge 41c
A plate 41 is created. This uneven shape with different depth is
Can be formed by multi-step exposure and etching.
Yes, by mastering using the uneven shape
The substrate 41 may be created. Next, as shown in FIG.
1, a magnetic layer 42 is formed by vacuum deposition, sputtering,
Soft vacuum deposition means such as ion plating
A film is formed with a magnetic material to a predetermined thickness. At that time, the magnetic layer 42
In the convex magnetic layer 42a on the convex 41a and in the concave 41b.
In addition to the concave magnetic layer 42b, unnecessary on the reinforcing edge 41c
A magnetic layer 42c is formed. Thereafter, the substrate 41 on which the magnetic layer 42 is formed is formed.
Polishing the surface, the unnecessary magnetic layer 4 on the reinforcing edge 41c
2c is removed, and the convex magnetic layer 42a is the same as the reinforcing edge 41c.
The master carrier 40 as shown in FIG.
Formed. According to this embodiment, the master carrier 40 has
The convex magnetic layer 42 a in the concave portion has a concave magnetic layer 42 at the periphery thereof.
reinforcement edge 41c of substrate 41 formed at the boundary with b
Reinforced by the
Even if repeatedly in contact with the groove medium 22, wear, abrasion,
Prevents peeling, missing, and edge changes, improving durability
The pattern shape changes at the same time
Without repeated, stable magnetic transfer can be performed, such as wear powder
Occurrence can also be reduced to prevent transfer defects. Note that the height of the reinforcing edge 41c of the substrate 41 is as follows.
May be lower than the thickness of the convex magnetic layer 42a. The master carrier 40 according to the present invention comprises the aforementioned
Magnetic transfer is performed in the same process as in FIG. Ie master
-The carrier 40 is initially set in the track direction or the vertical direction.
In close contact with the magnetized slave medium 22,
The initial magnetization direction is approximately
Applying a magnetic field for transfer in the opposite direction, the master carrier 4
The magnetization pattern corresponding to the transfer information of 0 is the slave medium 2
2 is transferred and recorded. As the substrate 41 of the master carrier 40, two
Use nickel, silicon, aluminum, alloy, etc.
The uneven pattern is formed by a stamper method or the like.
The The stamper method uses a glass plate with a smooth surface.
Photoresist by spin coating on (or quartz plate)
Servo signal while rotating this glass plate
A laser beam (or electron beam) modulated according to
Irradiated, the pattern of the convex magnetic layer 42a, for example, servo signal
The pattern corresponding to No. is exposed. Then photo cash register
Develop the strike, remove the exposed areas, and etch
Corresponds to the concave part where the convex magnetic layer 42a is embedded in the glass plate
A hole is formed. After removing the photoresist,
In the same manner as described above, a photoresist is formed again, and the recess 41b is patterned.
Expose the turn. Then develop the photoresist
Remove the exposed part and etch it into the glass plate
A hole corresponding to 41b is formed. Etching time
To change the depth of the recess. Also, the exposure order is reversed
But you can. And remove the photoresist
A master having a shape is obtained. Next, the uneven pattern on the surface of the master
The surface is plated (electroformed) to create irregularities.
A substrate having a pattern is prepared and peeled off from the master. Base
The depth of the concavo-convex pattern of the plate 41 (height of the convex portion 41a) is
The range of 80 nm to 800 nm is preferable, and more preferable
Is 100 nm to 600 nm. In addition, the second master is plated by plating the master.
Create a board and perform plating using this second master,
You may create the board | substrate which has the inverted uneven | corrugated pattern.
Furthermore, the second master is plated or the resin liquid is pressed
Curing is done to create a third master, and the third master is
To create a substrate with a concavo-convex pattern.
Yes. The magnetic layer 42 is formed as described above.
Soft magnetic materials can be deposited by vacuum evaporation, sputtering,
The film is formed by vacuum film forming means such as a rating method.
As the magnetic material, Co, Co alloy (CoNi, C
oNiZr, CoNbTaZr, etc.), Fe, Fe alloy
(FeCo, FeCoNi, FeNiMo, FeAlS
i, FeAl, FeTaN), Ni, Ni alloy (NiF
e) can be used. Particularly preferably FeCo,
FeCoNi. The thickness of the magnetic layer 42 is 50 nm to
The range of 500 nm is preferred, more preferably 100
nm to 400 nm. Hereinafter, implementation of another magnetic transfer method of the present invention will be described.
A form is demonstrated in detail. First, the magnetic transfer used for magnetic transfer
Copy master carrier and magnetic transfer master carrier
Is a slave medium to which predetermined information is magnetically transferred
The magnetic recording medium will be described. FIG. 6 shows a magnetic recording medium 51 and a master carrier.
FIG. The magnetic recording medium 51 has a longitudinal
A recording magnetic disk having a magnetic layer (recording layer) on a support 52;
Recording / reproducing layer) 53. In the figure, the recording
The raw layer 53 is provided only on one surface of the support 52
The recording / reproducing layer is formed on both sides.
Also good. The support is a hard substrate or a flexible substrate.
Either may be sufficient. The master carrier 54 is an annular disc.
Recorded on the magnetic recording medium 51.
According to information to be transferred to the raw layer 53 (for example, servo signal)
Substrate 55 having a convex pattern on the surface, and substrate 55
A soft magnetic layer 56 formed on the convex pattern of
The The soft magnetic layer 56 is formed on the convex pattern.
As a result, the master carrier 54 has a soft magnetic layer on the surface.
Provided with a pattern comprising a plurality of convex portions 57 having
It has become. Note that the master carrier 54 is in the form of this embodiment.
The soft magnetic layer is not limited to the configuration of the state.
Only formed on the top of the convex part of the turn, or only the concave part
It may be formed so as to embed the recess. Ma
When the substrate is made of a ferromagnetic material such as Ni
The substrate surface does not necessarily have to be coated with a soft magnetic layer.
The convex pattern provided on the surface itself “has a magnetic layer on the surface.
Equivalent to `` pattern consisting of multiple convex parts ''
The Furthermore, the convex part which consists of a soft-magnetic layer on a flat substrate.
May be formed in a pattern. The master carrier is a diamond on the top layer.
Cover with protective film such as dry carbon (DLC)
For example, this protective film improves contact durability and allows multiple magnetic
Transfer is possible and preferable. Furthermore, under the DLC protective film
Even if the Si film is formed on the layer by sputtering or the like
Good. The convex pattern of the substrate and the thickness of the magnetic layer
Multiple protrusions with a magnetic layer on the surface
The pattern consisting of is transferred to the magnetic layer of the magnetic recording medium.
Magnetic recording so that the desired magnetization pattern
Magnetization pattern transferred to magnetic layer of recording medium by magnetic transfer
Considering the effects of demagnetizing fields during magnetic transfer
Determine. That is, the pattern of the master carrier is a magnetic recording.
For the desired magnetization pattern transferred to the magnetic layer of the recording medium
It is formed so that it is not 1: 1. Specifically, the magnetic transfer medium to be processed
(Slave medium) of magnetic recording medium, master carrier
After determining each component material and pattern to be transferred, this
Check the transfer quality (for example, playback signal) with these combinations
Then, the pattern provided on the master carrier is corrected. For example, the magnetic layer 53 of the magnetic recording medium 51
As shown in FIG. 6, the desired magnetization pattern has a uniform magnetization interval.
It is assumed that the pattern is reversed at. When performing magnetic transfer
As described later, the magnetic layer 53 and the magnetic layer of the magnetic recording medium 51 are
Adhering or facing the magnetic layer 56 of the star carrier 54
Apply a transfer magnetic field. At this time, the magnetic layer of the magnetic recording medium 51
53 at the edge portion between the convex portions 57 of the master carrier 54
The opposing small region becomes a magnetization transition region. Therefore,
In the pattern of the magnetic recording medium 51 after copying, the transfer magnetic field
Due to the demagnetizing field when applied, the distance A between the convex portions of the master carrier 54
The width B of the region of the magnetic recording medium 51 facing the convex portion
If the width becomes narrower, narrow the width of the protrusions in advance and
A cell having a pattern in which the distance A is wider than the width B
Form a carrier. The demagnetizing field is applied to the slave medium (especially the thickness of the magnetic layer).
And magnetic properties), the pattern shape of the master carrier and
All the dimensions used for magnetic transfer
Since it is related to elements, it is determined by the inductive method as described above.
It is necessary to Magnetic transfer is a recording / reproduction of the magnetic recording medium 51.
The layer 53 and the soft magnetic layer 56 of the master carrier 54 are in close contact with each other.
Or in close contact with each other. FIG. 7 illustrates the basic steps of this magnetic transfer.
FIG. 7A is a diagram for explaining the initial recording of the magnetic recording medium.
(B) is a master carrier and a magnetic recording medium
And (c) is a step of applying a transfer magnetic field Hdu.
Indicates the magnetization state of the magnetic recording medium after air transfer.
It is a partial sectional view of the track longitudinal direction. In FIG.
As for the magnetic recording medium 51, its recording / reproducing layer 53 is used.
Only shows. As shown in FIG. 7A, a magnetic recording medium is previously provided.
51 Initial DC magnetic field Hin in one direction of track length
The magnetic layer 53 is initially DC magnetized by application. Thereafter, as shown in FIG.
Recording / reproducing layer 53 of magnetic recording medium 51 that has been initially DC magnetized
And soft magnetism on the convex pattern of the substrate 55 of the master carrier 54
Face the information carrying surface coated with the layer 56 (in the figure
In the opposite direction to the initial magnetization direction of the magnetic layer 53.
Magnetic transfer is performed by applying a transfer magnetic field Hdu in the direction. This
The magnetic layer 5 corresponding to the space between the convex portions 57 of the master carrier 54
Magnetization reversal occurs in a small area of 3, as shown in FIG.
As described above, the magnetic layer 53 of the magnetic recording medium 51 has a master bearing.
The information (eg servo signal) carried by the body 54 is magnetically
Transcribed and recorded. The initial DC magnetic field and transfer magnetic field are:
Slave medium holding power, master carrier and slave medium
It is necessary to adopt a value determined in consideration of the relative permeability of the body
is there. As described above, demagnetizing field correction is taken into consideration in advance.
The magnetic transfer mask of the present invention having a pattern formed as described above
If magnetic transfer is performed using a star carrier, a magnetic recording medium
The desired magnetic pattern is accurately transferred to
Especially when this information is a servo signal,
This leads to improved tracking servo performance.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing steps of a magnetic transfer method using a master carrier according to one embodiment of the present invention. FIG. 2 is a schematic diagram of a convex pattern of a master carrier. FIG. 4 is a cross-sectional view schematically showing an essential part of a master carrier according to another embodiment. FIG. 4 is a cross-sectional view showing an example of a production process of the master carrier. 6 is a cross-sectional view of the main part of the master carrier and the magnetic recording medium. FIG. 7 is a diagram showing the basic steps of the magnetic transfer method of the present invention. Description of reference numerals 2,22 Slave media 3, 40, 54 Master carriers 31, 41 Substrate 32 Soft magnetic layer (magnetic material) 32a Convex pattern 41a Convex part 41b Concave part 41c Reinforcement edge part 42 Magnetic layer 42a Convex part magnetic layer 42b Concave part magnetic layer 42c Unnecessary magnetic layer 51 Magnetic recording medium 52 Support 53 Magnetic layer ( Recording / reproducing layer) 56 Soft magnetic layer 7 protrusions R angle radius W track width rounded

   ─────────────────────────────────────────────────── ─── Continued front page    (31) Priority claim number Japanese Patent Application 2001-209317 (P2001-209317) (32) Priority Date July 10, 2001 (July 7, 2001) (33) Priority claim country Japan (JP) (31) Priority claim number Japanese Patent Application 2001-302233 (P2001-302233) (32) Priority date September 28, 2001 (September 28, 2001) (33) Priority claim country Japan (JP) (72) Inventor Masanori Yasunaga             2-1-12 Ogimachi, Odawara-shi, Kanagawa Prefecture             Shishi Photo Film Co., Ltd. F-term (reference) 5D006 BB07 CB07 DA04 EA03 FA00

Claims (1)

What is claimed is: 1. A magnetic transfer master carrier having a concavo-convex pattern made of a magnetic material corresponding to information to be transferred, the top corner of a substantially rectangular convex pattern formed on a substrate. A magnetic transfer master carrier characterized in that the radius R of the roundness of the planar shape is 1% or more and 47% or less with respect to the track width W.