JP2013058291A - Electron beam lithographic method and electron beam lithographic system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve accuracy of a drawing position in a circumferential direction when a fine pattern for a disk-like magnetic recording medium is drawn by electron beam scanning while rotating a rotary stage.SOLUTION: In principle, pattern drawing based on a drawing data signal group of each predetermined area in a circumferential direction of each radial position is started after a lapse (t+Δt) of a predetermined time period Δtfrom a predetermined encoder pulse Egenerated before the predetermined area is positioned at an electron beam radiation position. When rotation speed variations generates an encoder pulse Ethat should be generated after a lapse of the predetermined time period Δt, before a lapse of the predetermined time period Δtfrom the encoder pulse Ethat is a reference for starting drawing in the predetermined area, pattern drawing in the area is started at its occurrence time t'.

Description

  The present invention relates to an electron beam drawing method and an electron beam drawing method for drawing a fine pattern for a magnetic disk medium when producing a master such as an imprint mold master used for magnetic disk medium production or a master carrier for magnetic transfer. It is about the system.

  The present invention also provides a method for producing a concavo-convex pattern carrier including an imprint mold having a concavo-convex pattern surface or a master carrier for magnetic transfer, which is manufactured through a drawing process using an electron beam drawing method. The present invention relates to a method for manufacturing a magnetic disk medium in which a pattern is transferred using the concavo-convex pattern carrier.

  In current magnetic disk media, information patterns such as servo patterns are generally formed in advance. In addition, due to the demand for further increase in recording density, discrete track media (DTM) in which adjacent data tracks are separated by grooves to reduce magnetic interference between adjacent tracks has attracted attention. . In the bit pattern media (BPM) proposed to further increase the density, magnetic bodies (single domain fine particles) constituting a single magnetic domain are physically isolated and regularly arranged, and one fine particle is arranged. It is a medium for recording 1 bit.

  Conventionally, a fine pattern such as the servo pattern has been formed on a magnetic disk medium as a concavo-convex pattern or a magnetized pattern, an imprint mold for manufacturing a high-density magnetic disk medium, or a master disk for a magnetic transfer master carrier, etc. In addition, an electron beam drawing method for patterning a predetermined fine pattern has been proposed. In this electron beam drawing method, a master is placed on a rotating stage, and pattern drawing is performed by deflecting and scanning the electron beam on the master while rotating the master by rotating the rotating stage ( For example, see Patent Documents 1 to 3).

  In Patent Document 1, for example, when drawing a rectangular or parallelogram element extending in the width direction of a track constituting a servo pattern, an electron beam is deflected in a radial direction while being vibrated at high speed in the circumferential direction. There has been proposed a method of scanning and drawing so as to fill an element.

  In Patent Document 2, as an on / off drawing method, an electron beam is turned on / off in accordance with a pattern shape while rotating a substrate coated with a resist, and the substrate or the electron beam irradiation apparatus is rotated once per rotation. Drawing is performed for each beam width, drawing is performed by moving the drawing position in the radial direction for each rotation, a method for drawing a pattern of one track by a plurality of rotations, and an electron beam is reciprocally oscillated in the track width direction of the pattern. A method of drawing a pattern of one track by rotation is disclosed. Further, Patent Document 2 proposes a method of controlling the servo pattern drawing start timing.

  Patent Document 3 discloses a method for drawing a fine pattern for a discrete track medium, and a method for drawing a servo pattern and a groove pattern continuously for each track is proposed.

  In the electron beam drawing method, a method of drawing a pattern by synchronizing an encoder signal (encoder pulse) from an encoder that detects a rotation angle position of a drive motor that drives a rotary stage and a drawing clock generated by a formatter is generally used. Is. However, when this method is used, if there is uneven rotation speed of the drive motor that drives the rotary stage, an error occurs in the pattern arrangement in the circumferential direction.

  Cited Document 4 proposes a method of suppressing the position error of the drawing start position by starting drawing after a predetermined time has elapsed from the encoder pulse immediately before the drawing area.

JP 2004-158287 A JP 2006-1849249 A JP 2009-122217 A JP 2009-186581 A

  When drawing a groove pattern and a servo pattern based on an encoder pulse for each region as described in Patent Document 3, it is considered that the following problem occurs due to uneven rotation speed.

FIG. 10 is a diagram for explaining a problem that may occur between the areas of the groove pattern and the servo pattern.
For each region, drawing starts after a predetermined number of drawing clocks from a predetermined encoder pulse. Here, start drawing groove pattern G in 3 drawing clock cycle from the encoder pulses E _1, writing start time to start drawing of the servo pattern S from the next encoder pulse E ₂ to 3 drawing clock cycle (hereinafter, the index (Index) time) is set. The drawing data signal group includes continuous data signals, and each area is drawn based on a data signal for drawing each area.

As shown in FIG. 10, when the linear velocity of the rotation is normal, it starts the drawing based on the drawing data signal group Data groove pattern G (G) at time t _1, the circumferential length of Ln per writing clock Drawing is performed in the direction, and drawing based on the drawing data signal group Data (S) of the servo pattern S is started at the next index (time t ₂ ).

However, if the linear velocity of rotation at the time of drawing the groove pattern G is higher than normal, the length of Lf (> Ln) is drawn per drawing clock, and the data signal group Data (G) for the group pattern G is drawn. The drawing based on is not completed in the region (circumferential direction x _{1 to} x ₂ ) in which the groove pattern G is to be written, and i) the drawing overlaps in the head region (circumferential direction x _{2 to} x ₂ ′) of the servo pattern S , or ii) deviates from the original starting position x ₂ start position of the drawing of the servo pattern S (delayed) that may occur.

  When the linear velocity of rotation is slower than normal, the drawing based on the data signal group Data (G) for the groove pattern G is not sufficient to fill the area where the groove pattern G is to be written, and there is a gap between the servo pattern S and the servo pattern S. Can occur.

  As described above, if there is uneven rotation speed, the drawing areas overlap, the drawing start position is shifted, and further, the drawing area is skipped, resulting in a reduction in drawing accuracy.

  In particular, the overlap between the servo pattern and the groove and the deviation of the start position of the servo pattern that occur when the linear velocity of rotation is high may affect the servo accuracy, which is a problem.

  In addition, a multi-pass drawing method that draws a pattern during one rotation as described in Patent Document 2 with only one beam width by only on / off control of the irradiation beam and draws a pattern of one track by a plurality of rotations. Similar problems arise when used. In the case of the multi-pass method, since the drawing is performed at a high speed as compared with the method of drawing one track during one rotation while vibrating the electron beam, the shift of the pattern start position due to the rotation unevenness becomes large and the influence is great. .

  According to the study by the present inventors, there is a deviation of about 150 ns at maximum in the encoder interval due to rotation unevenness, and when the rotation speed is 180 rpm and the radial position is 15 mm, the deviation of the pattern position in the circumferential direction is about 40 nm at the maximum. It was. Similarly, when the calculation is performed at a rotation speed of 1000 rpm and a radial position of 15 mm, the deviation of the pattern position in the circumferential direction is about 220 nm at the maximum.

  The present inventor has proposed a method for preventing the occurrence of pattern overlap that occurs when the rotational speed is higher than normal, and for preventing the occurrence of gaps between patterns that occur when the linear velocity is low (Japanese Patent Application No. 2011-047691: unpublished at the time of this application).

  However, with respect to the pattern start position that occurs when the rotation speed is higher than normal, sufficient accuracy has not been improved.

  The present invention has been made in view of the above circumstances, and an electron beam drawing method and an electron beam drawing system that can improve the accuracy of the drawing start position in the circumferential direction of a pattern that sometimes occurs when the rotation speed is higher than normal. Is intended to provide.

  The present invention also provides a method for producing a concavo-convex pattern carrier such as an imprint mold or a magnetic transfer master carrier using the electron beam drawing method, and a concavo-convex pattern using the concavo-convex pattern carrier. Alternatively, it is an object of the present invention to provide a method for manufacturing a magnetic disk medium to which a magnetic pattern is transferred.

In the electron beam drawing method of the present invention, a fine pattern for a magnetic disk medium is drawn by scanning an electron beam on a master disk placed on a rotary stage equipped with a rotary encoder while rotating the rotary stage. An electron beam drawing method,
For each predetermined area in the circumferential direction of each radial position, a pattern based on a drawing data signal group for each predetermined area after a predetermined time has elapsed from a predetermined encoder pulse that occurs before the predetermined area is positioned at the electron beam irradiation position. In the electron beam drawing method for starting drawing,
If an encoder pulse that should occur after the lapse of the predetermined time occurs before the predetermined time elapses from the predetermined encoder pulse, the drawing of the predetermined area is performed without waiting for the predetermined time. Pattern drawing based on data of the data signal group is started.

  In other words, the electron beam drawing method of the present invention provides a predetermined encoder that occurs before a predetermined area is positioned at the electron beam irradiation position when the linear velocity of rotation of the rotary stage is normal (predetermined speed). After the elapse of a predetermined time from the pulse, pattern drawing based on the drawing data signal group for each predetermined area is started, but before the elapse of the predetermined time because the linear velocity of rotation is higher than normal. When an encoder pulse that should occur after the elapse of the predetermined time is generated, drawing is started without waiting for the predetermined time.

An electron beam drawing apparatus of the present invention includes a rotary stage equipped with a rotary encoder and an electron gun that emits an electron beam, and the electron beam is rotated while rotating the rotary stage on a master disk placed on the rotary stage. An electron beam drawing apparatus that scans and draws a pattern;
For each predetermined area in the circumferential direction of each radial position, a pattern based on a drawing data signal group for each predetermined area after a predetermined time has elapsed from a predetermined encoder pulse that occurs before the predetermined area is positioned at the electron beam irradiation position. A data signal generation and transmission device for generating a drawing data signal group for each of the predetermined areas so as to start drawing, and sequentially sending data signals of the drawing data signal group to the electron beam drawing device;
The data signal generation / transmission device has a memory for sequentially storing the drawing data signal group for each of the predetermined areas to be output to the electron beam drawing apparatus, and before starting pattern drawing for each of the predetermined areas in the memory. Is stored with a drawing data signal group corresponding to each predetermined area, and a data signal of the drawing data signal group stored in the memory is transmitted, and a predetermined time from the predetermined encoder pulse for the predetermined area If an encoder pulse that should occur after the elapse of the predetermined time occurs before the elapse of time, transmission of the data signal of the drawing data signal group in the predetermined area is started from the memory without waiting for the predetermined time. It is what is characterized by.

  The data signal generation / transmission device includes a plurality of the memories, and alternately stores the drawing data signal group for each of the predetermined areas to be output to the electron beam drawing apparatus in the plurality of memories according to a drawing order. It is preferable that the memory for transmitting the data signal is switched every time and the data signal of the drawing data signal group stored in the memory is transmitted.

  Preferably, the data signal generation / transmission device further includes a buffer memory, and the data signal is transmitted from the memory to the electron beam drawing device via the buffer memory.

  The method for producing a concavo-convex pattern carrier according to the present invention comprises drawing a fine pattern for a magnetic disk medium on a master by the electron beam drawing method of the present invention, and using the master on which the fine pattern is drawn, The method includes a step of forming a corresponding uneven pattern.

  Here, the concavo-convex pattern carrier is a carrier having a desired concavo-convex pattern shape on the surface, an imprint mold for transferring the concavo-convex pattern shape to a transfer medium, and a magnetized pattern corresponding to the concavo-convex pattern shape. For example, a magnetic transfer master carrier for transferring to a transfer medium.

  Using the imprint mold, which is a method for producing a magnetic disk medium of the present invention, and a concavo-convex pattern carrier produced by the production method of the present invention, the concavo-convex pattern corresponding to the concavo-convex pattern provided on the surface of the mold is transferred. Including a process. Specific examples of magnetic disk media manufactured by this manufacturing method include discrete track media and bit pattern media.

  Another magnetic disk medium manufacturing method of the present invention uses a magnetic transfer master carrier, which is a concavo-convex pattern carrier manufactured by the manufacturing method of the present invention, in accordance with the concavo-convex pattern provided on the surface of the master carrier. And a step of magnetically transferring the magnetized pattern.

  According to the electron beam drawing method of the present invention, when an encoder pulse that should occur after a predetermined time has elapsed before a predetermined time elapses from a predetermined encoder pulse for a predetermined area, the predetermined time is waited. Without starting the pattern drawing based on the data of the drawing data signal group of the predetermined area, it is possible to prevent the pattern start position from shifting backward when the linear velocity of rotation increases due to rotation unevenness, Drawing accuracy can be improved. If the pattern is a servo pattern, improving the accuracy of the pattern drawing start position results in an improvement in servo accuracy.

  The electron beam drawing system of the present invention has a memory for sequentially storing a drawing data signal group for each predetermined area to be output to the electron beam drawing apparatus, and the memory for each predetermined area before the pattern drawing is started. A drawing data signal group corresponding to each predetermined area is stored, a data signal of the drawing data signal group stored in the memory is transmitted, and a predetermined time elapses from the predetermined encoder pulse for the predetermined area. If an encoder pulse that should occur after the elapse of the predetermined time has occurred before starting, data for starting transmission of the data signal of the drawing data signal group in the predetermined area from the memory without waiting for the predetermined time Since the signal generating and transmitting apparatus is provided, the electron beam drawing method of the present invention can be easily realized.

It is the principal part side view (a) and partial top view (b) of the electron beam drawing system of one Embodiment which implements the electron beam drawing method of this invention. The top view which shows the fine pattern for discrete track media drawn on the original disc by the electron beam drawing method of this invention 2 is an enlarged view of a part of the fine pattern of FIG. The figure which shows the timing chart of the pattern drawing in embodiment of the electron beam drawing method of this invention The figure for demonstrating the rotational speed and drawing pattern at the time of drawing the servo pattern following a groove pattern by the electron beam drawing method of this invention Diagram for explaining the timing of drawing start when the rotation speed increases The figure which shows the timing chart of the pattern drawing of the example of a design change of the electron beam drawing method Schematic sectional view showing the process of transferring and forming a fine pattern using an imprint mold Cross-sectional schematic diagram showing the transfer process of magnetized pattern using magnetic transfer master Diagram for explaining problems that may occur at pattern boundaries due to uneven rotation in conventional high-speed vibration method drawing methods

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

"Electron beam drawing system"
First, an embodiment of the electron beam writing system of the present invention for carrying out the electron beam writing method of the present invention will be described. FIG. 1 is a block diagram showing a schematic configuration of an electron beam drawing system.
The electron beam drawing system 100 includes an electron beam drawing device 40 and a data signal generation / transmission device 50. The electron beam drawing device 40 rotates an electron beam irradiation unit 20 that irradiates an original beam with an electron beam, and rotates and straightens the master. And a mechanical drive unit 30 to be moved.

  The electron beam irradiation unit 20 emits an electron beam EB into the lens barrel 18, deflects the electron beam EB in the radial direction Y and the circumferential direction X, and performs micro reciprocating vibration with a constant amplitude in the circumferential direction X. Aperture 25 and blanking 26 (deflector) are provided as deflection means 22 and 23 for turning on and off and blanking means 24 for turning on / off irradiation of the electron beam EB, and the electron beam EB emitted from the electron gun 21 is The light is irradiated on the master (here, the substrate 10 coated with the resist 11) through the deflecting means 22 and 23 and an electromagnetic lens (not shown).

  The aperture 25 in the blanking means 24 has a through-hole through which the electron beam EB passes at the center, and the blanking 26 deflects the electron beam EB at the time of an on signal in accordance with an on / off signal of EB irradiation. Without passing through the aperture 25 without being passed, the electron beam EB is deflected and blocked by the aperture 25 without passing through the aperture 25 to irradiate the electron beam EB. Operates not to.

  The mechanical drive unit 30 includes a rotary stage 31 that supports the master in a housing 19 with the lens barrel 18 disposed on the upper surface, and a spindle motor 32 that has a motor shaft provided so as to coincide with the central axis of the stage 31. The rotary stage unit 33 is provided, and linear movement means 34 for linearly moving the rotary stage unit 33 in one radial direction of the rotary stage 31. The linear moving means 34 includes a rod 35 that is screwed into a part of the rotary stage unit 33 and is precisely threaded, and a pulse motor 36 that drives the rod 35 to rotate forward and backward. The stage unit 33 is provided with an encoder 37 that outputs an encoder signal corresponding to the rotation angle of the rotary stage 31. The encoder 37 includes a rotating plate 38 that is attached to the motor shaft of the spindle motor 32 and has a large number of radial slits, and an optical element 39 that optically reads the slits and outputs an encoder signal. Note that the encoder signal may vary based on the rotational speed unevenness of the motor 32.

  The data signal generating / transmitting device 50 is configured so that, for each predetermined region in the circumferential direction of each radial position of the hard disk pattern, after a predetermined time elapses from a predetermined encoder pulse generated before each predetermined region is positioned at the electron beam irradiation position, A drawing data signal group for each predetermined region is generated so as to start pattern drawing based on each drawing data signal group, and data signals of the drawing data signal group are sequentially sent to the electron beam drawing apparatus 40.

  The data signal generation and transmission device 50 includes a design data storage unit 52 that stores design data (such as a drawing pattern and data indicating drawing timing) related to a pattern to be drawn, and a drawing clock generation that generates a drawing clock for measuring the drawing timing. And a data distribution unit 60 that generates a drawing data signal group based on the design data and sends the drawing data signal group to the electron beam drawing apparatus 40. The data signal generation / transmission device 50 can be constituted by a so-called formatter.

  The design data relating to the pattern to be drawn is sent from the external design data processing device constituted by a personal computer (not shown) to the data signal generating / sending device 50 before starting the electron beam drawing, and the design data storage unit 52 Accumulated in.

  The data distribution unit 60 of the data signal generation / transmission device 50 uses the design data stored in the design data storage unit 52 to generate data for generating a drawing data signal group for each predetermined area to be output to the electron beam drawing device 40. Unit 61, a plurality of memories 62 and 63 for alternately storing a drawing data signal group in accordance with a drawing order, a signal output unit 68 for sending a drawing data signal to the electron beam drawing apparatus 40, a signal output unit 68 and a plurality of signals A buffer memory 66 connected to the memories 62 and 63 is provided.

The data signal generation / transmission device 50 switches a plurality of memories 62, 63 that transmit data signals for each drawing of each predetermined area by a switching means 65, and the memories 62, 63 (hereinafter referred to as memory 1 and memory 2). The data signals of the drawing data signal group stored in (1) are sequentially transmitted. Although two memories 62 and 63 are provided here, three or more memories may be provided.
Data signals from the memories 62 and 63 are input to the signal output unit 68 via the buffer memory 66, and are sent from the signal output unit 68 to the electron beam drawing apparatus 40. By using the buffer memory 66, it is possible to prevent a delay in data signal output when the memories 62 and 63 are switched.

  The switching timing of the memory for reading the drawing data signal is determined by a predetermined encoder pulse and a drawing clock that are preset for each predetermined area in the circumferential direction. An index is assigned after a predetermined time has elapsed (a predetermined number of drawing clocks) from a predetermined encoder pulse generated before the predetermined area is positioned at the electron beam irradiation position, and the data signal generation and transmission device 50 is based on this index. The memory is switched. This memory switching corresponds to the timing at which pattern drawing based on a drawing data signal group for each predetermined area is started.

  When starting the pattern drawing, the data signal generating / transmitting device 50 is a memory 62 in which a part of the data signal of the drawing data signal group for drawing the groove pattern in the predetermined area immediately before the predetermined area is transmitting the data signal. Even when the data remains, the memory 63 that stores the drawing data signal group in the predetermined area is switched to start transmission of the data signal of the drawing data signal group from the memory 63.

The data signal generation / transmission device 50 switches the memory based on the index assigned to the drawing clock in principle, and transmits the data signal.
However, the data signal generation / transmission device 50 should occur after the generation of this index before a predetermined time elapses from a predetermined encoder pulse for a certain predetermined area, that is, before an index for a certain predetermined area is generated. When an encoder pulse is generated (detected), transmission of the data signal of the drawing data signal group in the predetermined area is started without waiting for the predetermined time (index).

  Further, as described above, the data signal generation / transmission apparatus 50 generates a drawing data signal group of a pattern to be drawn in the predetermined area for each predetermined area as described above. As a drawing data signal group for drawing a pattern, it is desirable that a drawing data signal group including a number of data signals larger than the number of data signals corresponding to a predetermined region is generated and stored in a memory.

  The drawing clock generation unit 54 includes a reference clock generation unit that generates an invariant reference clock, and generates a drawing clock based on the reference clock.

In the present electron beam drawing system 100, the data signal generation and transmission device 50 includes drawing data including control signals such as blanking on / off control, XY deflection control of the electron beam EB, and rotation speed control of the rotary stage 31. A signal group is generated for each predetermined area, and the drawing data signal is distributed to each amplifier and driver. Each data signal is transmitted at a predetermined timing based on an encoder pulse and a drawing clock input from the encoder 37. Is done.
In the electron beam drawing apparatus 40, the spindle motor 32 is driven, that is, the rotation speed of the rotary stage 31, the pulse motor 36 is driven, that is, the linear movement is performed by the linear moving means 34, the electron beam EB is modulated, the deflection means 22 and 23 are controlled, The on / off control of the blanking 26 of the blanking means 24 is performed based on the drawing data signal transmitted from the data signal generating / transmitting device 50.

"Electron beam drawing method"
Next, an embodiment of the electron beam drawing method of the present invention using the above-described electron beam drawing system 100 will be described.
FIG. 2 is an overall plan view showing a fine pattern (hard disk pattern) of a magnetic disk medium to be drawn on the master by the electron beam drawing method of the present invention, and FIG. 3 is an enlarged view of a part of this fine pattern.

  2 and 3 show fine patterns for discrete track media. A fine pattern for discrete track media is composed of servo patterns S formed in servo areas 12 and groove patterns G formed in data areas 15 alternately arranged in the circumferential direction. It is formed in an annular region excluding the portion 10a and the inner peripheral portion 10b.

  The servo pattern S is formed on the concentric tracks of the substrate 10 at equal intervals, and in each sector, in a narrow radial servo region 12 that is curved from the center. The servo pattern S includes, for example, patterns corresponding to a preamble, an address, and a burst signal. FIG. 3 is an enlarged view of a portion of the preamble portion.

  On the other hand, the groove pattern G is formed concentrically extending in the track direction so as to separate adjacent tracks.

  In the final discrete track medium, the drawing portion of the groove pattern G and the servo pattern is a concave portion, and the other portion is a flat portion (land) made of a magnetic layer. The recess may be embedded with a nonmagnetic material.

  The servo pattern S and the groove pattern G are drawn, for example, from a track on the inner peripheral side while rotating a master disk made of a substrate 10 coated with a resist 11 on the surface on a rotary stage 31 (see FIG. 1). The resist 11 is irradiated and exposed by scanning with the electron beam EB one track at a time in order to the outer track or in the opposite direction. The substrate 10 is made of, for example, silicon, glass, or quartz.

FIG. 4 is a diagram showing a timing chart for executing the electron beam drawing method of the present invention. In the present embodiment, the groove pattern G and the servo pattern S for one track are drawn at a time by one rotation of the substrate 10.
The groove pattern G is drawn while maintaining the state in which the electron beam is irradiated to a certain drawing position while rotating the substrate 10 (rotation stage 31). On the other hand, the servo pattern S scans the elements S ₁ , S ₂ ,... Over the track width with the electron beam EB having a small diameter so as to fill the shape of the substrate 10 while rotating the substrate 10. The servo pattern S is drawn. Note that a servo element (for example, a burst signal) shifted by a half track across adjacent tracks may be drawn at a time by shifting the drawing reference by a half track without being divided in half.

  The scanning of the electron beam EB that fills the element is performed by controlling the on / off of the irradiation of the electron beam EB by the operation of the blanking means 24, and the electron beam EB having a beam diameter smaller than the minimum track direction length of the servo element. XY deflection is performed in a direction orthogonal to Y and the radial direction (hereinafter referred to as circumferential direction X), and with a constant amplitude in the circumferential direction X orthogonal to the radial direction Y, according to the rotational speed of the substrate 10 (rotary stage 31). This is done by reciprocating at high speed.

This will be described in more detail based on FIG.
4A shows the drawing operation of the electron beam EB in the radial direction Y and the circumferential direction X of the electron beam EB. FIG. 4B shows the deflection signal Def (Y) in the radial direction Y, and FIG. The deflection signal Def (X) in the direction X, the vibration signal Mod (X) in the circumferential direction X in (D), the on / off operation of EB irradiation in (E), the encoder pulse in (F), (G) The drawing clocks are shown respectively.

  First, as described above, the groove pattern G is irradiated with the electron beam EB with the EB irradiation signal turned on without being deflected in the radial direction and the circumferential direction and without vibrating in the circumferential direction. Draw by rotating. The drawing of the groove pattern G is divided into a plurality of predetermined areas, and drawing is started at an index time based on the encoder pulse for each predetermined area. A continuous groove pattern formed in one data area 15 may be continuously drawn over one data area without synchronization with an encoder pulse, but is divided into a plurality of predetermined areas. Thus, the synchronization at the boundary between the groove pattern G and the servo pattern S can be suppressed by synchronizing with the predetermined encoder pulse for each predetermined area.

Drawing of the servo element S ₁ of the servo pattern S starts drawing at an index time set after a predetermined time Δt _{2 has} elapsed from the time when the predetermined encoder pulse E _{2 is} generated. The EB irradiation signal is turned on, and the electron beam EB at the reference position is reciprocally oscillated in the circumferential direction X by the vibration signal Mod (X) of (D), and in the radial direction by the deflection signal Def (Y) of (B). (−Y) to be deflected and sent, and in order to compensate for the deviation of the irradiation position of the electron beam EB accompanying the rotation of the substrate 10, the deflection signal Def (X) of (C) is the same direction as the rotation direction ( by sending by deflecting the -X), and scanned to fill the servo element S ₁ of the rectangular shape, by blanking the off EB irradiation signal to stop the irradiation of the electron beam EB, the servo element S ₁ drawing Exit. Thereafter, the deflection in the radial direction Y and the circumferential direction X is returned to the reference position.

Next, the substrate 10 is rotated at a drawing position of the servo elements S _2, S ₃ · · ·, while reciprocally vibrating the electron beam EB as with drawing servo elements S ₁ in the circumferential direction X, radial and rotational Drawing is performed with deflection in the direction.

Circumferential direction of the drawing start position of the element S ₁ which is placed at the beginning of the servo pattern S, by servo region starts drawing from the encoder pulse E ₂ occurring immediately prior to the position at the writing position after a predetermined time Delta] t ₂ elapses, Since positioning is performed with high accuracy, the accuracy of the formation position of the servo pattern S in one round can be increased. Note that the encoder pulse used as a reference for the index time is not limited to the previous one as long as it is generated before the servo area is positioned at the drawing position. However, the accuracy can be further improved by using the encoder pulse generated immediately before the drawing position as a reference.

  After one track is drawn, the next track is moved and drawn in the same manner, and a desired fine pattern is drawn in the entire region of the substrate 10. The track movement (movement in the radial direction) of the drawing position is performed by deflecting the electron beam EB in the radial direction Y, or by linearly moving the rotary stage 31 in the radial direction Y. As described above, the rotary stage may be moved linearly for each drawing of a plurality of tracks or for each drawing of one track according to the deflectable range of the electron beam EB in the radial direction Y. However, since it is more efficient to move in the radial direction by the deflecting means, the track movement is performed by deflecting in the range in which radial movement by the deflecting means is possible, and after drawing a plurality of tracks, It is preferable that the deflection in the radial direction by the deflecting unit is once canceled and the rotary stage is moved in the radial direction by a plurality of tracks using the linear moving unit 34.

  In addition, the rotation stage is set so that the drawing speed of the drawing portion in the drawing area of the substrate 10 in the radial direction, that is, the track movement, has the same linear velocity in the entire drawing area in both the outer peripheral portion and the inner peripheral portion of the substrate 10. It is preferable to adjust the rotation speed of 31 so as to be slow when drawing on the outer peripheral side and fast when drawing on the inner peripheral side, and perform drawing with the electron beam EB from the viewpoint of obtaining a uniform irradiation dose and securing the drawing position accuracy.

The beam intensity of the electron beam EB is set such that the resist 11 can be sufficiently exposed by the high-speed vibration drawing of the servo elements S ₁ , S ₂ . That is, the drawing width (substantially exposed width) by the electron beam EB has a characteristic that it becomes wider than the irradiation beam diameter and amplitude according to the irradiation time and amplitude, and in order to draw the final element width, the drawing width is used. In order to scan with a predetermined irradiation dose, the irradiation dose is regulated by adjusting the amplitude and the deflection speed. Note that it is difficult to change the beam intensity during drawing in terms of beam stability.

  Control of the pattern drawing start timing of each region in the electron beam drawing method of this embodiment will be described with reference to FIGS.

  FIG. 5 is a diagram for explaining the drawing and drawing start timing of the groove pattern G and the servo pattern S subsequent thereto, and shows the drawing timing by the encoder pulse and the drawing clock, and the drawing pattern for each linear velocity due to rotation unevenness. FIG. In order to facilitate understanding, FIG. 5 schematically shows a drawing data signal group stored in the memory 1 and the memory 2 for drawing a pattern in each region.

As shown in FIG. 5, the drawing of the groove pattern G in a predetermined area (circumferential positions x ₁ to x ₂ ) is based on a predetermined encoder pulse E that occurs before the position x ₁ is positioned at the EB irradiation position. The index time starts after a predetermined time (Δt) elapses from the pulse E generation time t. Here, the predetermined time Δt is set to 3 drawing clocks. Similarly servo pattern S drawing, with respect to the predetermined encoder pulse E _n occurring immediately before the position x ₂ is located in the EB irradiation position, the index pulse E _n generation time t _n from a predetermined time (Delta] t _n) after It starts at time t _n + Δt _n .

  When drawing the groove pattern G, the data signals of the groove pattern data signal group Data (G) stored in the memory 1 of the data signal generating / transmitting device 50 are drawn by the electron beam via the buffer memory 66 and the signal output unit 68. Assume that the data is being sent to the device 40. The memory 1 stores a group pattern data signal group Data (G) that includes more data than the number of data signals required to draw a predetermined area when rotation is normal (linear velocity is normal). Has been.

When the linear velocity is normal, a length of Ln is drawn per drawing clock, and at the index time t ₂ + Δt _{2 at} the start of servo pattern drawing, excess data is not yet sent but remains in the memory 1, but switching By switching to the memory 2 by the means 65, the sending of the data signals of the servo pattern data signal Data (S) stored in the memory 2 to the buffer memory 66 is started, and the servo pattern drawing to the next predetermined area is started. Is started.

If the linear velocity is higher than normal at the time of groove pattern drawing, the length of Lf (> Ln) is drawn per drawing clock, so drawing of the predetermined area is completed with less data than normal. However, as in the normal state, when the servo pattern drawing start index time t _n + Δt _n is reached, even if a data signal that has not yet been transmitted remains in the memory 1, the switching means 65 switches to the memory 2. Then, transmission of the data signals of the servo pattern data signal group Data (S) stored in the memory 2 to the buffer memory 66 is started, and servo pattern drawing is started.

Further, in the present embodiment, when the linear velocity is slower than normal, only the length of Ls (<Ln) per drawing clock can be drawn. The number of data is required. In the present embodiment, as the drawing data signal group Data (G) of the groove pattern, when the rotation is normal (linear velocity is normal) in the memory 1, the number of data signals required for drawing a predetermined area is determined. Since the group pattern data signal group Data (G) including a large number of data is stored, even if the linear velocity is low, there is no drawing omission in the predetermined area. Also in this case, at the servo pattern drawing start time t _n + Δt _n , the switching means 65 switches to the memory 2 and the data signal buffer of the servo pattern data signal group Data (S) stored in the memory 2 is stored. Transmission to the memory 66 is started, and servo pattern drawing is started.

  In any case, the storage of the servo pattern data signal Data (S) in the memory 2 is completed before the servo pattern drawing is started. During the signal transmission from the memory 2, the drawing data signal group Data (G) of the previous groove pattern is erased (discarded) from the memory 1, and the groove pattern to be newly drawn next to the servo pattern is stored in the memory 1. A drawing data signal group is stored.

As the predetermined region described above, in principle, an index time t _n after the lapse of a predetermined time Delta] t _n from the generation time t _n of a predetermined encoder pulse E _n which is the start of a reference drawing predetermined for each It is set to start drawing at + Δt _n . However, if the rotational speed is largely deviated partially, if the drawing is performed in principle, the drawing start position is also greatly deviated from the desired position (design position).

  Therefore, in the electron beam drawing method of the present invention, when the rotation speed becomes higher than a certain level, the following control is performed. FIG. 6 is a diagram for explaining the control of the drawing start timing when the rotation is faster than a certain level.

As shown in FIG. 6, in the case without rotation unevenness, is set as the encoder pulse E _{n + 1} from the generation time t _n of the encoder pulse E _n after the index time t _{n +} Delta] t _n after a predetermined time Delta] t _n passed occurs Suppose that Here, when the rotation irregularities there, before the encoder pulse E _{n + 1} should result inherently from the generation time t _n of a predetermined encoder pulse E _n after a predetermined time Delta] t _n has passed said predetermined constant-time Delta] t _n (i.e., the index at time t _The rotational speed may be partially increased to the extent that it occurs before _n + Δt _n ). In such a case, if drawing is started at the index time t _n + Δt _n , the drawing position will be greatly shifted in the circumferential direction. Therefore, when the encoder pulse _{E n + 1} occurs before coming the index time _{t n} + _{Δt n,} without waiting for the index time _{t n} + _{Δt n,} to start the drawing at a time t _{'n + 1} encoder pulse _{E n + 1} has occurred. At this time, even if the data signal of the drawing data signal group for the predetermined area immediately before that still remains, the remaining data signal is forcibly switched and the memory is forcibly switched. It is assumed that pattern drawing is started.
By performing such control, it is possible to prevent a significant shift in the pattern drawing start position that occurs when the rotation speed increases due to uneven rotation.

Incidentally, the linear velocity of the rotating even faster than normal, if the occurrence time of the encoder pulse E _{n + 1} in the same manner as in the normal is later than the index time t _{n +} Δt _n, the pattern drawn on the basis, the index time To start. The detection time of the next encoder pulse earlier than the index time as shown in FIG. 6 is a case where the rotational linear velocity has greatly changed beyond a certain value. In such a case, as described above By performing the control, significant position fluctuations can be effectively suppressed.

As described above, in the electron beam drawing method of the present embodiment, the groove pattern does not extend and is drawn in a predetermined area where the servo pattern is to be drawn, and the groove pattern end position accuracy can be improved. The accuracy of the start position of each pattern area when the rotation becomes faster can be improved.
Furthermore, by preparing an excessive data signal as a drawing data signal group of the groove pattern in advance, even if the rotation is slowed down, the groove pattern is drawn over the entire area where the groove pattern is to be drawn. Since the drawing omission does not occur, the accuracy of the end position of the groove pattern can be improved.

In the embodiment described above, the servo pattern is drawn after the groove pattern. However, the groove elements G ₁ and G ₂ are obtained by dividing the groove pattern G to be formed in one data area into a plurality of predetermined areas in the circumferential direction. Accuracy improvement of the groove element end position and start position between... Gn can be realized in the same manner.

When drawing a groove pattern by dividing it into a plurality of predetermined areas, each groove element may perform drawing without performing electron beam deflection scanning, or a direction perpendicular to the radial direction of the electron beam in units of groove elements. It is also possible to perform deflection scanning in the (circumferential direction X) and draw the groove elements Gn (n = 1, 2,...) Sequentially with a time interval as the substrate rotates (Japanese Patent Laid-Open No. 2009-122217). See the official gazette).
Also in this case, when the next index (drawing start time of the next group element G _{n + 1} ) occurs during deflection scanning in the electron beam circumferential direction X for drawing of the groove element G _n , If the drawing of the next group element G _{n + 1} is started, when the linear velocity increases due to uneven rotation, the drawing may overlap between the groove elements or at the boundary between the groove pattern and the servo pattern. It is possible to prevent the start position from being shifted backward, and to improve the pattern drawing accuracy. When an encoder pulse that should occur after the index of the next group element G _{n + 1} is detected before the drawing start index is generated, drawing of the next group element is started by detecting the encoder pulse. By doing so, it is possible to effectively suppress a large shift in the drawing start position of each group element.

  In the above embodiment, the encoder pulse is counted based on the rise time, but the encoder pulse fall time or both the rise and fall times may be counted.

  In the above embodiment, as a drawing method, a method of drawing an element in a servo pattern is described in which the electron beam is vibrated at high speed in the circumferential direction and the element shape is filled by deflecting in the radial direction. The electron beam may be vibrated at high speed in the radial direction. Further, one track may be drawn by a plurality of rotations using a multi-pass method (ON / OFF drawing method).

`` Design change example ''
A design change example of the electron beam drawing method and the electron beam drawing system will be described. Here, a case where a fine pattern for a magnetic disk medium is drawn by a multi-pass method will be described based on a timing chart shown in FIG. Here, a drawing pattern of a master carrier for magnetic transfer is drawn. A fine pattern for a magnetic disk medium carried on a master carrier for magnetic transfer is similar to a pattern for a discrete track medium in that it has data areas and servo areas arranged alternately in the circumferential direction. Have no groove pattern and only have a servo pattern in the servo area. Although it is conceivable to write data in the data area in advance, it is assumed here that there is no pattern drawing in the data area.

7A shows the drawing operation of the electron beam EB, FIG. 7B shows the on / off operation of EB irradiation, (C) the encoder pulse, (D) the drawing clock, and (E) the time axis. Respectively.
The deflection of the electron beam EB is not controlled during one-track scanning, but only on / off of irradiation. As shown in FIG. 7A, one track is drawn here with six rotations. The element S ₁ of the servo pattern S is divided into S _1-1 , S _1-2 ... S _1-6 blocks, and S _{1-1 in} the first rotation, S _{1-2 in the} second rotation, and so on. One block is drawn every rotation.
Drawing of the servo pattern S is started from the generation time _{t n} of a predetermined encoder pulse _{E n} to the index time _{t n} + Delta] t _n for a predetermined time (Delta] t _n) after. EB irradiation on / off control is performed according to the number of clocks corresponding to each element, and one block of each element of the servo pattern S is drawn during one rotation. In the data area, EB irradiation is turned off.
After one rotation, the electron beam is deflected by one block in the radial direction, and a block adjacent to the previously drawn block is drawn in the next rotation. By repeating this a plurality of times (here, 6 times), a pattern of one track is drawn.

Also in the case of the drawing method of the present design change example, when the rotation speed is changed, the rotation speed is significantly increased as shown in FIG. 6, and before the servo region drawing start index time t _n + Δt _n , When an encoder pulse E _{n + 1} that should occur after the index time t _n + Δt _n is generated, pattern drawing is started at the generation time t ′ _{n + 1} of the encoder pulse.

  As described above, when drawing by the multi-pass method, it is necessary to perform a plurality of rotations for drawing one track, but there is no need for complicated control such as beam deflection scanning during one rotation. Thus, the rotational speed is set to be very large as compared with the drawing method in which one track is drawn. As the number of rotations increases, the amount of drawing pattern shift due to rotation unevenness increases. Therefore, in the multi-pass method, the effect of suppressing the pattern drawing start position shift is more remarkable than in the above-described embodiment.

  If there is no pattern to be drawn in the data area, there is a time during which no pattern is drawn between the drawing area. At this time, the data signal generation / transmission device 50 only needs to be able to store the drawing data signal group corresponding to the pattern of the next servo area in the memory after the pattern drawing to a certain predetermined servo area and before the pattern of the next servo area is started. Therefore, a single memory may be used. Further, the buffer memory may not be provided. In the case of a single memory, no memory switching means is required, and the data signal generation / transmission device 50 only needs to be configured to transmit the data signal of the drawing data signal group from the memory at the drawing start time.

<Imprint mold manufacturing method and magnetic disk medium manufacturing method>
Next, a method of manufacturing an imprint mold (one form of a concavo-convex pattern carrier) including the step of drawing a fine pattern by the above-described electron beam drawing method by the electron beam drawing system 100 as described above, and the imprint mold A method for manufacturing the magnetic disk medium used will be described. FIG. 8 is a schematic cross-sectional view showing a process of transferring and forming a fine concavo-convex pattern using an imprint mold.

  In the imprint mold 70, the above-described resist 11 (not shown in FIG. 8) is applied to the surface of the substrate 71 made of a translucent material, and the servo pattern S and groove pattern for discrete track media are applied by the drawing method of the above-described embodiment. G is drawn. Thereafter, development processing is performed to form a concavo-convex pattern with a resist on the substrate 71. The substrate 71 is etched using the patterned resist as a mask, and then the resist is removed to obtain an imprint mold 70 having a fine uneven pattern 72 formed on the surface. As an example, the fine uneven pattern 72 includes a servo pattern and a groove pattern for discrete track media.

  Using this imprint mold 70, a magnetic disk medium 80 is manufactured by an imprint method. The magnetic disk medium 80 includes a magnetic layer 82 on a substrate 81, and a resist resin layer 83 for forming a mask layer is coated thereon. Then, the fine uneven pattern 72 of the imprint mold 70 is pressed against the resist resin layer 83, the resist resin layer 83 is cured by ultraviolet irradiation, and the uneven shape of the fine pattern 72 is transferred and formed. Thereafter, the magnetic layer 82 is etched based on the concavo-convex shape of the resist resin layer 83 to produce a magnetic disk medium 80 for discrete track media in which a fine concavo-convex pattern is formed by the magnetic layer 82.

  In the above description, the manufacture of discrete track media has been described. However, bit pattern media can also be manufactured in the same process.

<Manufacturing method of magnetic transfer master carrier and manufacturing method of magnetic disk medium>
Next, a manufacturing method of a magnetic transfer master carrier (one form of a concavo-convex pattern carrier) including a step of drawing a fine pattern by the above-described electron beam drawing method by the electron beam drawing apparatus 100 as described above, and the magnetic transfer thereof A method for manufacturing a magnetic disk medium using the master carrier for the apparatus will be described. FIG. 9 is a schematic cross-sectional view showing the process of magnetically transferring the magnetization pattern to the magnetic disk medium 85 using the magnetic transfer master carrier 90.

  The manufacturing process of the magnetic transfer master carrier 90 is almost the same as the manufacturing method of the imprint mold 70. The substrate 10 placed on the rotary stage 31 is coated with an electron beam drawing resist 11 on the surface of a disk made of, for example, silicon, glass, or quartz, and the electron beam is scanned on the resist 11 to form a desired pattern. draw. Thereafter, the resist 11 is developed to obtain a substrate 10 having a fine concavo-convex pattern of the resist. This becomes a master disk of the master carrier 90 for magnetic transfer.

  Next, a thin conductive layer is formed on the concavo-convex pattern surface of the master, and electroforming is performed thereon to obtain a substrate 91 having a concavo-convex pattern taking a metal mold. Thereafter, the substrate 91 having a predetermined thickness is peeled from the master. The uneven pattern on the surface of the substrate 91 is obtained by inverting the uneven shape of the master.

  After the back surface of the substrate 91 is polished, a magnetic layer 92 (soft magnetic layer) is coated on the uneven pattern to obtain a magnetic transfer master carrier 90. The convex or concave shape of the concave / convex pattern of the substrate 91 is a shape depending on the concave / convex pattern of the resist of the master.

  A method for manufacturing a magnetic disk medium using the magnetic transfer master carrier 90 manufactured as described above will be described. The magnetic disk medium 85 that is a transfer medium to which information is transferred is, for example, a hard disk, a flexible disk, or the like in which the magnetic recording layer 87 is formed on both surfaces or one surface of the substrate 86. Here, the magnetization of the magnetic recording layer 87 The perpendicular magnetic recording medium is formed so that the easy direction is perpendicular to the recording surface.

  As shown in FIG. 9A, an initial direct current magnetic field Hin is applied to the magnetic disk medium 85 in one direction perpendicular to the track surface in advance to cause the magnetic recording layer 87 to undergo initial direct current magnetization. Thereafter, as shown in FIG. 9B, the surface on the recording layer 87 side of the magnetic disk medium 85 and the surface of the magnetic layer 92 of the master carrier 90 are brought into close contact with each other, and the direction perpendicular to the track surface of the magnetic disk medium 85 is obtained. In addition, magnetic transfer is performed by applying a transfer magnetic field Hdu in the direction opposite to the initial DC magnetic field Hin. As a result, as shown in FIG. 9C, the magnetic field for transfer is sucked into the magnetic layer 92 of the master carrier 90, and the magnetization of the magnetic layer 87 of the magnetic disk medium 85 in the portion corresponding to the convex portion is reversed. As a result, the information (for example, servo signal) corresponding to the concavo-convex pattern of the master carrier 90 is magnetically transferred and recorded on the magnetic recording layer 87 of the magnetic disk medium 85. When magnetic transfer is also performed on the upper recording layer of the magnetic disk medium 85, an upper master carrier is brought into close contact with the upper recording layer, and magnetic transfer is performed simultaneously with the lower recording layer.

  In the case of magnetic transfer to the in-plane magnetic recording medium, a master carrier 90 substantially the same as that for the perpendicular magnetic recording medium is used. In the case of this in-plane recording, the magnetization of the magnetic disk medium is preliminarily magnetized in one direction along the track direction in advance, and is in close contact with the master carrier for transfer in a direction substantially opposite to the initial DC magnetization direction. Magnetic transfer is performed by applying a magnetic field, the magnetic field for transfer is sucked into the convex magnetic layer of the master carrier 90, and the magnetization of the magnetic layer of the magnetic disk medium corresponding to the convex part is not reversed, As a result of reversal of the magnetization of the other portions, a magnetization pattern corresponding to the concavo-convex pattern can be recorded on the magnetic disk medium.

  The above-described manufacturing method of the imprint mold and the magnetic transfer master carrier using the electron beam writing method of the present invention described above is an example, and pattern writing is performed using the electron beam writing method of the present invention. The manufacturing method is not limited to the above as long as it undergoes a process of forming a pattern.

10 Board
11 resist
12 Servo area
15 Data area
20 Electron beam irradiation unit
30 Mechanical drive
37 Encoder
40 Electron beam lithography system
50 Data signal generator
60 Data distribution part
61 Data generator
62,63 memory
66 Buffer memory
70 Imprint mold
71 board
72 Fine uneven pattern
80 Magnetic disk media
81 board
82 Magnetic layer
83 Resist resin layer G Groove pattern S Servo pattern
EB electron beam

Claims (7)

An electron beam writing method for drawing a fine pattern for a magnetic disk medium by scanning an electron beam while rotating the rotary stage on a master disk placed on a rotary stage equipped with a rotary encoder,
For each predetermined area in the circumferential direction of each radial position, a pattern based on a drawing data signal group for each predetermined area after a predetermined time has elapsed from a predetermined encoder pulse that occurs before the predetermined area is positioned at the electron beam irradiation position. In the electron beam drawing method for starting drawing,
If an encoder pulse that should occur after the lapse of the predetermined time occurs before the predetermined time elapses from the predetermined encoder pulse, the drawing of the predetermined area is performed without waiting for the predetermined time. An electron beam drawing method, wherein pattern drawing based on data of a data signal group is started. An electron having a rotary stage equipped with a rotary encoder and an electron gun for emitting an electron beam, and drawing a pattern by scanning the electron beam while rotating the rotary stage on a master placed on the rotary stage A beam drawing device;
For each predetermined area in the circumferential direction of each radial position, a pattern based on a drawing data signal group for each predetermined area after a predetermined time has elapsed from a predetermined encoder pulse that occurs before the predetermined area is positioned at the electron beam irradiation position. A data signal generation and transmission device for generating a drawing data signal group for each of the predetermined areas so as to start drawing, and sequentially sending data signals of the drawing data signal group to the electron beam drawing device;
The data signal generation / transmission device has a memory for sequentially storing the drawing data signal group for each of the predetermined areas to be output to the electron beam drawing apparatus, and before starting pattern drawing for each of the predetermined areas in the memory. Is stored with a drawing data signal group corresponding to each predetermined area, and a data signal of the drawing data signal group stored in the memory is transmitted, and a predetermined time from the predetermined encoder pulse for the predetermined area If an encoder pulse that should occur after the elapse of the predetermined time occurs before the elapse of time, transmission of the data signal of the drawing data signal group in the predetermined area is started from the memory without waiting for the predetermined time. An electron beam drawing system characterized by that.   The data signal generation / transmission device includes a plurality of the memories, and alternately stores the drawing data signal group for each of the predetermined areas to be output to the electron beam drawing apparatus in the plurality of memories according to a drawing order. 3. The electron beam drawing system according to claim 2, wherein a memory for sending a data signal is switched every time and a data signal of a drawing data signal group stored in the memory is sent.   4. The electron according to claim 2, wherein the data signal generation and transmission device further includes a buffer memory, and the data signal is transmitted from the memory to the electron beam drawing device via the buffer memory. Beam drawing system.   A method of drawing a desired fine pattern on a master by the electron beam drawing method according to claim 1 and forming a concave / convex pattern corresponding to the fine pattern using the master on which the fine pattern is drawn. A method for producing a concavo-convex pattern carrier characterized by the above.   A step of transferring an uneven pattern corresponding to the uneven pattern provided on the surface of the mold using an imprint mold that is an uneven pattern carrier manufactured by the manufacturing method according to claim 5 is included. A method of manufacturing a magnetic disk medium.   Using a magnetic transfer master carrier, which is a concavo-convex pattern carrier manufactured by the manufacturing method according to claim 5, and magnetically transferring a magnetization pattern corresponding to the concavo-convex pattern provided on the surface of the master carrier. A method for manufacturing a magnetic disk medium.

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