JP2007059006A - Method for manufacturing original disk, method for manufacturing stamper and method for manufacturing magnetic recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing an original disk by which an original disk having a transfer surface with fine and complicated rugged patterns equivalent to servo information is manufactured with high precision, a method for manufacturing a stamper and a method for manufacturing a magnetic recording medium using the same. <P>SOLUTION: A resin layer 44 formed on a substrate (resin layer support material) 42 is processed to an irregular rugged pattern in which a projected part 44A for division is formed at a part of a recessed part of a predetermined basic rugged pattern to the basic rugged pattern and at least a part of the recessed part of the basic rugged pattern is divided, the substrate 42 is etched based on the resin layer 44 and the substrate 42 is processed to a recessed pattern in a form in which the irregular rugged pattern is made close to the basic rugged pattern. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to, for example, a stamper master manufacturing method, a stamper manufacturing method, and a magnetic recording medium manufacturing method using these stampers, which are used for forming an uneven pattern in a manufacturing process of a semiconductor product, an information recording medium, and the like.

  2. Description of the Related Art Conventionally, in a semiconductor product manufacturing process, a technique called lithography is used in which a resin layer of a resist material is formed on a resin layer support material, and this is exposed and developed to process it into a concavo-convex pattern. By etching the resin layer support material using the resin layer of the uneven pattern as a mask, the resin layer support material can be processed into an uneven pattern following the uneven pattern of the resin layer. In recent years, processing of fine concavo-convex patterns with a pitch of several hundred nm or less may be required. When such fine concavo-convex patterns are formed, the influence of the wavelength of light used for exposure cannot be ignored. An electron beam may be used for this purpose. However, the method of performing exposure (drawing) for each semiconductor product using an electron beam has a problem that productivity is low.

  On the other hand, a method called an imprint method is known in which a stamper is brought into contact with a resin layer to transfer a concavo-convex pattern (see, for example, Patent Document 1). When transferring a fine concavo-convex pattern having a pitch of several hundred nm or less, it is sometimes referred to as a nanoimprint method. It should be noted that the resin layer remains at the bottom of the recess and the resin layer support material is not exposed only by transferring the concavo-convex pattern by contacting the stamper, but the resin layer is etched uniformly enough to remove the resin layer at the bottom of the recess. By doing so, the resin layer support material can be exposed from the bottom of the recess, and the resin layer can be used as a mask by the amount of the transferred uneven step.

  According to the imprint method, productivity can be greatly increased compared to the method of performing exposure using an electron beam for each product, and in the field of magnetic recording media such as hard disks due to the following circumstances. Improvement of productivity by such an imprint method is expected.

  The magnetic recording medium is divided into a plurality of data areas and a plurality of servo areas, and servo information for head positioning and the like is recorded and used in the servo areas. Each servo area is divided into a plurality of grid-like areas, and the servo information has a configuration in which either 0 or 1 information is binary recorded in each area according to a predetermined rule. Servo information includes, for example, a preamble portion for clock synchronization, a SAM portion indicating the start of servo data, a track address signal portion indicating a track number, a sector address signal portion indicating a sector number, and a burst signal for tracking a magnetic head It consists of parts. Such servo information is usually recorded on a magnetic recording medium by a servo track writing method. The servo information recording process involves sequentially magnetizing each grid-like area in the servo area for each magnetic recording medium, resulting in a problem of low productivity. Particularly in recent years, due to the improvement of the surface recording density and the accompanying decrease in the flying height of the head, the servo information is also required to be recorded with high density and high accuracy. There is a growing need for improvement.

  On the other hand, in the servo area portion of the recording layer, the grid-like area for recording one of the information of 0 and 1 is a recess unit area constituting the recess, and the other information is recorded. It has been proposed to form a concavo-convex pattern corresponding to servo information in which a grid-like region is a convex unit region constituting a convex part (see, for example, Patent Documents 2 and 3). In this way, a magnetic recording medium in which a portion of the servo area of the recording layer is formed with a concavo-convex pattern corresponding to servo information is applied so that the recording layer is magnetized in accordance with the servo information pattern by applying a DC magnetic field uniformly. Servo information recording efficiency can be greatly improved.

  In addition, magnetic recording media such as hard disks have been remarkably improved in surface recording density due to improvements such as miniaturization of magnetic particles constituting the recording layer, change of materials, and miniaturization of head processing. Although the improvement in surface recording density is expected, recording of incorrect information on other tracks adjacent to the recording target track due to the processing limit of the magnetic head, the expansion of the recording magnetic field of the magnetic head, and the cross at the time of reproduction Problems such as talk have become obvious, and the improvement of surface recording density by these conventional improvements has reached its limit, and the recording layer is a data area as a candidate for a magnetic recording medium that can further improve the surface recording density. Have proposed a discrete track medium or a patterned medium in which a recording element is formed as a convex portion of a concave / convex pattern. When manufacturing discrete track media or patterned media, there is a step of processing the recording layer to form the recording elements as convex portions in the data area, and at the same time, the servo area portion of the recording layer is also formed into an uneven pattern. Since it can be processed, it is particularly advantageous in terms of production efficiency.

  Thus, in order to process the recording layer into a concavo-convex pattern corresponding to servo information or the shape of a track, it is expected to use an imprint method using a stamper as described above. When processing the recording layer into a concavo-convex pattern, a resin layer may be formed directly on the recording layer, but depending on circumstances such as the material of the recording layer and the type of etching, there is a gap between the recording layer and the resin layer. There has also been proposed a method in which one or a plurality of mask layers are formed, these are sequentially etched based on the resin layer of the concavo-convex pattern, and the recording layer is processed into the concavo-convex pattern.

  By the way, although different from the imprint method, in the field of optical recording media, a stamper is used to form uneven patterns such as pits and grooves on a substrate. Specifically, a stamper is disposed in a mold, and a resin material such as polycarbonate is injection-molded to obtain a substrate on which concave and convex patterns for information transmission such as pits and grooves are formed.

  A method for manufacturing a stamper for an optical recording medium has been established, and an example thereof will be briefly described here. First, a resin layer of a resist material is formed on a substrate such as glass, and the master layer having a concave / convex pattern on the surface is obtained by partially removing the resin layer by exposure and development using a lithography technique. Next, a conductive film is formed on the surface of the master by electroless plating or vapor deposition. Next, an electroplating layer made of Ni (nickel) or the like is formed by electroplating using the electroconductive film as an electrode, and the conductive film and the electroplating layer are integrally peeled off from the master to obtain a stamper (for example, Patent Documents) 4). Note that the stamper obtained in this way is opposite in concave and convex relative to the master, but the conductive film and the electroplating layer peeled off from the master are used as a metal master (master). If a stamper is produced, a stamper having a concave / convex positional relationship with the master can be obtained. Furthermore, the electrolytic plating method may be repeated once or a plurality of times to produce another metal master from the metal master.

  It is expected that the stamper manufacturing method established in the field of optical recording media will be used for manufacturing stampers for semiconductor products and magnetic recording media.

Japanese Patent Laid-Open No. 2003-100609 JP-A-6-195907 JP-A-9-259426 Japanese Patent Laid-Open No. 5-205321

  However, it has been difficult to accurately process the resin layer into a fine and complicated uneven pattern corresponding to servo information by lithography. In particular, the track address signal portion has a complicated pattern, and it has been difficult to form a concavo-convex pattern corresponding to the track address signal portion on the master with sufficient accuracy. Therefore, it has been difficult to produce a stamper having a transfer surface with a fine and complicated uneven pattern corresponding to servo information with sufficient accuracy.

  The present invention has been made in view of the above problems, and a master manufacturing method capable of manufacturing a master having a fine and complicated uneven pattern corresponding to servo information with high accuracy, and a stamper using the master It is an object to provide a manufacturing method and a manufacturing method of a magnetic recording medium.

  In the present invention, a resin layer formed on a resin layer support material is divided into a concave portion of the basic concavo-convex pattern with respect to a predetermined basic concavo-convex pattern. Processing into an irregular concavo-convex pattern in which at least a part of the concave portion of the pattern is divided, and etching the resin layer support material based on the resin layer to form the irregular concavo-convex pattern close to the basic concavo-convex pattern The above object is achieved by processing the resin layer support material.

  Further, the present invention provides a resin layer formed on a resin layer support material, wherein a split convex portion is formed on a part of the concave portion of the basic concavo-convex pattern with respect to a predetermined basic concavo-convex pattern. Processed into an irregular concavo-convex pattern in which at least a part of the concave portion of the concavo-convex pattern is divided, and further, the resin layer is etched into the concavo-convex pattern in a form in which the irregular concavo-convex pattern is close to the basic concavo-convex pattern The above object is achieved by processing.

  Further, in the present invention, the resin layer formed on the resin layer support material has at least a part of the corners of the protrusions protruding from the adjacent recesses with respect to a predetermined basic uneven pattern. The irregular concavo-convex pattern is processed by processing the irregular concavo-convex pattern including the protruding portion protruding toward the concave portion adjacent to the corner portion of the basic concavo-convex pattern, and etching the resin layer support material based on the resin layer. The object is achieved by processing the resin layer support material into a concavo-convex pattern in a form close to the concavo-convex pattern.

  Further, in the present invention, the resin layer formed on the resin layer support material has at least a part of the corners of the protrusions protruding from the adjacent recesses with respect to a predetermined basic uneven pattern. Processed into an irregular concavo-convex pattern including a protrusion protruding toward the concave portion adjacent to the corner portion of the basic concavo-convex pattern, and further etching the resin layer to bring the irregular concavo-convex pattern closer to the basic concavo-convex pattern The said objective is achieved by processing this resin layer in the uneven | corrugated pattern of a form.

  In the process of conceiving the present invention, the inventors have intensively studied the reason why it is difficult to form a fine and complicated uneven pattern with high accuracy, and the following factors can reduce the processing accuracy. I got the insight that it is high in nature.

  When processing a resin layer into a fine and complicated concavo-convex pattern by lithography, it is important to adjust the exposure dose to an appropriate value. If the dose is adjusted to a value that is appropriate for some of the parts, the dose may be excessive or insufficient for other parts, and the resin layer cannot be accurately processed into the desired uneven pattern. It is thought that there is.

  On the other hand, by exposing the resin layer with an exposure pattern corresponding to an irregular concavo-convex pattern in which at least a part of the concave portion of the basic concavo-convex pattern is divided, the range of the width of the exposed portion corresponding to the concave portion However, the exposure dose can be adjusted to a value close to the appropriate value for the entire area, and the resin layer can be increased to an irregular concavo-convex pattern. Can be processed with accuracy. Note that the dividing protrusions are significantly smaller in width than the other protrusions of the resin layer, and when the resin layer is etched or the resin layer support material is etched based on the resin layer, the dividing protrusions of the resin layer Corresponding convex portions of the mask layer and the resin layer support material are removed faster than other convex portions. Therefore, the resin layer support material or the resin layer can be processed into a basic concavo-convex pattern or a concavo-convex pattern in which the irregular concavo-convex pattern is close to the basic concavo-convex pattern.

  Also, in the process of etching the resin layer or etching the resin layer support material based on the resin layer, the corners of the protrusions protruding into the adjacent recesses among the protrusions of the resin layer are particularly easily removed and rounded. It is easy to be processed into a rounded shape, and the corner of the convex portion of the resin layer support material under the resin layer is also easily processed into a rounded shape. Therefore, it is considered that the resin layer support material or the resin layer may not be processed into a desired uneven pattern.

  On the other hand, the resin layer has a concave portion in which at least a part of the corner of the convex portion protruding toward the adjacent concave portion is adjacent to the basic concave / convex pattern than the corner portion of the basic concave / convex pattern corresponding to the corner portion. It is exposed with an exposure pattern corresponding to an irregular concavo-convex pattern including protrusions projecting to the side, processed into this irregular concavo-convex pattern by development, and then the resin layer is etched or the resin layer support material based on the resin layer Are removed, the protrusions at the corners of the resin layer, the corresponding mask layer, and the protrusions at the corners of the protrusions of the resin layer support material are removed, and these corners are the basic equivalents of these. Since it is processed into a shape close to the corner of the concavo-convex pattern, the resin layer and the resin layer support material can be processed into a basic concavo-convex pattern or a concavo-convex pattern in which the irregular concavo-convex pattern is close to the basic concavo-convex pattern.

  That is, the above-described object can be achieved by the following present invention.

  (1) With respect to a predetermined basic concavo-convex pattern, the resin layer formed on the resin layer support material is formed with split convex portions in a part of the concave portions of the basic concavo-convex pattern. An irregular concavo-convex pattern forming step for processing an irregular concavo-convex pattern in which at least a part of the concave portion is divided, and etching the resin layer support material based on the resin layer to convert the irregular concavo-convex pattern into the basic concavo-convex pattern And a resin layer support material etching step of processing the resin layer support material into a concavo-convex pattern in a form close to the pattern.

  (2) In (1), between the irregular irregular pattern forming step and the resin layer support material etching step, the resin layer is etched to select the dividing convex portion among the convex portions of the resin layer. A method for manufacturing a master, which is provided with a resin layer etching step for removing the substrate.

  (3) In (1) or (2), a mask layer that functions as a mask for etching in the resin layer support material etching step is formed between the resin layer support material and the resin layer, and the irregular A mask layer etching step for etching the mask layer based on the resin layer is provided between the concave / convex pattern forming step and the resin layer support material etching step while removing the dividing protrusions of the resin layer. A method of manufacturing a master disc characterized by the above.

  (4) In any one of (1) to (3), in the resin layer support material etching step, the resin layer support material is etched so as to form a continuous recess under the dividing projection. A method for producing a master disc.

  (5) With respect to a predetermined basic concavo-convex pattern, the resin layer formed on the resin layer support material has a concavo-convex portion formed on a part of the concave portion of the basic concavo-convex pattern. An irregular concavo-convex pattern forming step of processing into an irregular concavo-convex pattern in which at least a part of the concave portion is divided, and the concavo-convex pattern in a form in which the irregular concavo-convex pattern is brought close to the basic concavo-convex pattern by etching the resin layer And a resin layer etching step for processing the resin layer.

  (6) In (5), in the resin layer etching step, the resin layer is etched so as to selectively remove the dividing projections among the projections of the resin layer. Method.

  (7) In any one of (1) to (6), the concave / convex pattern on the master is divided into a plurality of data areas and a plurality of servo areas, and each servo area is further divided into a plurality of grid-like areas. Then, information of any one of 0 and 1 is binary-recorded on the recording layer according to a predetermined rule and used in each of the grid-shaped areas, and the recording layer includes the part of the servo area. The recording layer of the magnetic recording medium formed with a concave-convex pattern in which one of the 0 and 1 information is recorded as a concave portion and the other information is recorded as a convex portion. The basic concavo-convex pattern corresponds to a concavo-convex pattern, and the basic concavo-convex pattern is a checkered pattern in which any one of the 0 and 1 information is recorded in the checkered area of the servo area of the recording layer. The part corresponding to the area A concave-convex pattern in which a portion corresponding to a grid-shaped region in which the other information is recorded is a convex unit region, and in the irregular concave-convex pattern forming step, the resin layer is formed with the basic concave-convex portion. An irregular concavo-convex pattern in which the dividing convex portion is formed in the vicinity of the boundary between at least two continuous concave portion unit regions of the concave portion unit region, and the concave portions divided into the continuous concave unit regions are formed. A method of manufacturing a master, characterized by processing the resin layer.

  (8) In (7), the irregular concavo-convex pattern is used for the division in the vicinity of a boundary between at least two concave unit regions continuous in the radial direction of the magnetic recording medium among the concave unit regions of the basic concavo-convex pattern. A method of manufacturing a master, wherein the pattern is a concavo-convex pattern in which convex portions are formed and concave portions divided in the radial direction are formed in the continuous concave unit regions.

  (9) In any one of (1) to (8), in the irregular concavo-convex pattern forming step, the resin layer may be at least a corner of a convex portion that protrudes into an adjacent concave portion with respect to the basic concavo-convex pattern. A method of manufacturing a master, characterized in that an irregular concavo-convex pattern including a protrusion that protrudes toward a concave portion adjacent to a corner portion of the basic concavo-convex pattern corresponding to the corner portion.

  (10) The basic structure in which at least a part of the corners of the convex portions protruding from the adjacent concave portions corresponds to the corner portions of the resin layer formed on the resin layer support material with respect to a predetermined basic concave-convex pattern. An irregular concavo-convex pattern forming step for processing into an irregular concavo-convex pattern including a protrusion protruding toward the concave portion adjacent to the corner portion of the concavo-convex pattern, and etching the resin layer support material based on the resin layer And a resin layer support material etching step of processing the resin layer support material into a concavo-convex pattern in which the irregular concavo-convex pattern is close to the basic concavo-convex pattern.

  (11) A resin layer formed on a resin layer support material, wherein the basic layer has at least a part of a corner of a convex portion protruding from an adjacent concave portion corresponding to a predetermined basic concave-convex pattern. An irregular concavo-convex pattern forming process including a protrusion protruding toward the concave portion adjacent to the corner of the concavo-convex pattern, and the irregular concavo-convex pattern by etching the resin layer to form the basic concavo-convex pattern. And a resin layer etching step of processing the resin layer into a concavo-convex pattern in a form close to the concavo-convex pattern.

  (12) In any one of (1) to (11), a resist material is used as the material of the resin layer, and in the irregular concavo-convex pattern forming step, the resin layer is processed into the irregular concavo-convex pattern by exposure and development. A master disk manufacturing method characterized by:

  (13) An electroplating step of forming an electroplating layer by an electroplating method on the master manufactured by the master manufacturing method according to any one of (1) to (12). Stamper manufacturing method.

  (14) In (13), the electroplating step is a first electroplating step, and after the first electroplating step, a peeling step of peeling the metal master including the electroplated layer from the master, and the metal A stamper manufacturing method, comprising: a second electroplating step of forming either a stamper or another metal master on the master by electrolytic plating.

  (15) A method for producing a magnetic recording medium, comprising the step of transferring a concavo-convex pattern corresponding to the concavo-convex pattern of the recording layer using the stamper produced by the method for producing a stamper according to (13) or (14). .

  In the present application, the term “irregular uneven pattern in which the irregular uneven pattern is close to the basic uneven pattern” means that the irregular uneven pattern has fewer parts different from the basic uneven pattern than the irregular uneven pattern. To do.

  In the present application, “processing the resin layer support material into a concavo-convex pattern” means that the resin layer support material is partially removed in the thickness direction to form a continuous film or member having both concave and convex portions. In addition to processing the resin layer support material, the resin layer support material may be divided in such a way that the resin layer support material is divided so that the resin layer support material remains only on the convex portions, or the convex portions are partially continuous. It is used for the meaning including the case of processing.

  Further, in this application, “etching the resin layer support material based on the resin layer” means that the resin layer support material is etched using the resin layer of the uneven pattern directly formed on the resin layer support material as a mask. In addition, one or a plurality of other layers such as a mask layer are formed between the resin layer support material and the resin layer, and these layers are sequentially etched based on the resin layer of the concavo-convex pattern.

  Further, in this application, “information of 0 and 1” is binary recorded on the recording layer like information given by being magnetized and information given by being not magnetized. Therefore, it is used in the meaning of two types of information to which different magnetic characteristics that can be distinguished in binary are given.

  In addition, the term “magnetic recording medium” in the present application is not limited to a hard disk, a floppy (registered trademark) disk, a magnetic tape, or the like that uses only magnetism for recording and reading information, and MO (Magneto) using both magnetism and light. It is used in the meaning including a magneto-optical recording medium such as Optical) and a heat-assisted recording medium using both magnetism and heat.

  According to the present invention, a fine and complicated uneven pattern corresponding to servo information can be formed with high accuracy.

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

  The first embodiment of the present invention is a method of manufacturing a master 40 as shown in FIG. 9, and a method of manufacturing a stamper 10 having a transfer surface 10A with a concavo-convex pattern as shown in FIGS. The present invention also relates to a method of manufacturing a magnetic recording medium 12 as shown in FIGS.

  In order to understand the first embodiment, first, the configuration of the magnetic recording medium 12 will be briefly described.

  The magnetic recording medium 12 is a disk-shaped perpendicular recording type discrete track medium, which is divided into a plurality of data areas DA and a plurality of servo areas SA, and each servo area SA is further shown in FIGS. These are divided into a plurality of grid-like areas, and information of either 0 or 1 is binary-recorded on the recording layer 14 according to a predetermined rule and used.

  The recording layer 14 is a concave / convex portion in which the servo area SA is a concave area in the area where either 0 or 1 information is recorded in the grid-like area, and a convex area in which the other information is recorded. It is formed with a pattern. In FIGS. 5 and 6, the hatched area is a convex part and the other area is a concave part. 4 to 6, the symbol Dc indicates the circumferential direction of the magnetic recording medium 12, and the symbol Dr indicates the radial direction.

  Specifically, the servo area SA of the recording layer 14 includes a preamble section 16 for clock synchronization, a SAM (Servo Address Mark) section 18 indicating the start of servo data, and a track address signal section 20 indicating a track number. , A sector address signal portion 22 indicating a sector number, and a burst signal portion 24 for detecting the position of the magnetic head in each recording element 14A (track) of the data area DA. 5 and 6 show a part of the track address signal section 20 in an enlarged manner. 4 shows the shape of the convex portion of the recording layer 14 in the servo area SA as a linear shape parallel to the radial direction Dr for convenience. As shown in FIGS. The convex portion actually has a width in the circumferential direction Dc.

  Further, the data area DA of the recording layer 14 is divided into concentric arcs, and a large number of recording elements 14A that are long in the circumferential direction Dc constituting the track are formed as convex portions at a predetermined track pitch in the radial direction Dr. Has been.

The recording layer 14 has a thickness of 5 to 30 nm and is formed on the substrate 26 as shown in FIG. The recording layer 14 is made of a CoCr alloy such as a CoCrPt alloy, a FePt alloy, a laminate thereof, or a material in which ferromagnetic particles such as CoPt are included in a matrix in an oxide material such as SiO _2. Etc. can be used. Further, as the material of the substrate 26, a nonmagnetic material such as glass, NiP-coated Al alloy, Si, Al ₂ O ₃ or the like can be used.

Fillers 28 are filled in the recesses between the recording elements 14A in the data area DA and the recesses between the protrusions of the recording layer 14 in the servo area SA. As a material of the filler 28, nonmagnetic materials such as oxides such as SiO ₂ , Al ₂ O ₃ , TiO ₂ and ferrite, nitrides such as AlN, and carbides such as SiC can be used.

  A protective layer 30 and a lubricating layer 32 are formed in this order on the recording layer 14 and the filler 28. The protective layer 30 has a thickness of 1 to 5 nm. As a material of the protective layer 30, for example, a hard carbon film called diamond-like carbon can be used. The lubricating layer 32 has a thickness of 1 to 2 nm. As the material of the lubricating layer 32, a fluorine-based lubricant such as PFPE (perfluoropolyether) can be used.

  Further, between the substrate 26 and the recording layer 14, magnetic anisotropy in the thickness direction (direction perpendicular to the surface) is imparted to the antiferromagnetic layer 34, the soft magnetic layer 36, and the recording layer 14. The alignment layer 38 is formed. The antiferromagnetic layer 34 has a thickness of 5 to 50 nm. As a material of the antiferromagnetic layer 34, a PtMn alloy, a RuMn alloy, or the like can be used. The soft magnetic layer 36 has a thickness of 50 to 300 nm. As a material of the soft magnetic layer 36, Fe (iron) alloy, Co (cobalt) amorphous alloy, ferrite, or the like can be used. The alignment layer 38 has a thickness of 2 to 40 nm. As a specific material of the alignment layer 38, nonmagnetic CoCr alloy, Ti, Ru, a laminate of Ru and Ta, MgO, or the like can be used.

  Next, a method for manufacturing the stamper 10 will be described with reference to a flowchart shown in FIG.

  First, the master 40 shown in FIG. 9 is prepared. The master 40 is configured to include a substrate 42 having one surface processed into a concavo-convex pattern, and a mask layer 43 formed on the convex portion of the substrate 42. The material of the substrate 42 is Si, and the material of the mask layer 43 is Ni.

  First, an unprocessed substrate (resin layer support material) 42 having flat surfaces is washed, and a mask layer 43 is formed on one surface of the substrate 42 by sputtering or the like with a uniform thickness. After forming (not shown), the resin layer 44 is formed by a spin coating method, and a master disk processing starting body 45 as shown in FIG. 10 is produced (S102). The material of the resin layer 44 is a positive resist material. Furthermore, the solvent in the resin layer 44 is evaporated and dried by baking, and the film thickness and defects of the resin layer 44 are inspected.

  Next, the resin layer 44 is irradiated with a laser beam or an electron beam, and the basic uneven pattern as shown in FIG. 11 corresponding to the uneven pattern on the transfer surface 10A of the stamper 10 is compared with one of the concave portions of the basic uneven pattern. A concave portion of the irregular concavo-convex pattern is formed with an exposure pattern corresponding to the irregular concavo-convex pattern as shown in FIG. 12 in which the division convex portion 44A is formed in the portion and at least a part of the concave portion of the basic concavo-convex pattern is divided. Is drawn so as to be exposed (S104). In FIGS. 11 and 12, the hatched part is a convex part and the other part is a concave part.

  In the basic concavo-convex pattern, among the grid-like areas of the servo area portion of the recording layer 14, the area corresponding to the grid-like area in which any one of the information 0 and 1 is recorded is the concave unit area CU. The area corresponding to the grid-like area in which the other information is recorded is a concavo-convex pattern in which the convex unit area PU.

  On the other hand, the irregular concavo-convex pattern is such that, with respect to the basic concavo-convex pattern, the division convex portion 44A is arranged in the vicinity of the boundary between at least two continuous concave unit regions CU among the concave unit regions CU, and the continuous concave unit regions It is the uneven | corrugated pattern into which the recessed part of CU was divided | segmented. The irregular concavo-convex pattern has a non-convex portion 44A for division formed in the vicinity of the boundary between at least two concave unit units CU continuous in the radial direction Dr in the concave unit region CU, and the concave portions of the continuous concave unit unit CU. Is preferably a concavo-convex pattern divided in the radial direction Dr.

  Next, the exposed portion of the resin layer 44 is removed by development and processed into the irregular concavo-convex pattern shown in FIG. 12 (S106). By exposing a portion corresponding to the concave portion of the irregular concavo-convex pattern in which at least a part of the concave portion of the basic concavo-convex pattern is divided in the resin layer 44, the range of the width of the exposed portion is the width of the basic concavo-convex pattern. Since it is more limited than the case where the portion corresponding to the concave portion is exposed, the exposure dose can be adjusted to a value close to an appropriate value for the entire region, and the resin layer 44 is shown in FIGS. In addition, it can be processed into irregular irregular patterns with high accuracy.

Next, the mask layer 43 is etched by ion beam etching using Ar gas as a processing gas (S108). At this time, the convex portions of the resin layer 44 are also etched, and the dividing convex portions 44A are significantly smaller in width than the other convex portions of the resin layer 44 and are removed faster than the other convex portions. The resin layer 44 is etched so that a continuous recess is formed in a portion corresponding to 44A. That is, the resin layer 44 is processed into a basic concavo-convex pattern or a concavo-convex pattern in which the irregular concavo-convex pattern is close to the basic concavo-convex pattern. Accordingly, as shown in FIG. 14, the mask layer 43 is also processed into a basic concavo-convex pattern or a concavo-convex pattern in which the irregular concavo-convex pattern is close to the basic concavo-convex pattern. In addition, after processing the mask layer 43, the resin layer 44 on the convex portion is removed by reactive ion etching using O ₂ or O ₃ as a reactive gas.

  Next, the substrate 42 is etched by reactive ion etching using a fluorine-based gas as a reactive gas, and the substrate 42 is processed into a basic concavo-convex pattern or a concavo-convex pattern in which the irregular concavo-convex pattern is close to the basic concavo-convex pattern ( S110). As a result, the master 40 shown in FIG. 9 is obtained.

  Next, as shown in FIG. 15, a conductive film 48 is formed on the surface of the master 40 by vapor deposition or electroless plating (S112), and an electrolytic plating layer is formed on the conductive film 48 by electrolytic plating. 50 is deposited (S114). Specifically, the master 40 on which the conductive film 48 is formed is dipped in a nickel sulfamate solution, and a nickel film is grown by energizing the conductive film 48 as an electrode to form the electrolytic plating layer 50. To do. The conductive film 48 and the electrolytic plating layer 50 are integrally peeled from the master 40. In addition, since the resin layer 44 may adhere to the peeled conductive film 48 and the electrolytic plating layer 50, the resin layer 44 is removed with an organic solvent, and the conductive film 48 and the electrolytic plating layer 50 are removed as necessary. The outer periphery and the like are punched to adjust the shape, and the surface of the electrolytic plating layer 50 opposite to the conductive film 48 is polished, and then ultrasonically cleaned with ultrapure water. As a result, the stamper 10 having the transfer surface 10A having the concavo-convex pattern shown in FIG. 2 is obtained. The concave / convex pattern on the transfer surface 10 </ b> A of the stamper 10 is opposite to the concave / convex pattern on the master 40.

  As described above, the resin layer 44 is divided into the basic uneven pattern corresponding to the uneven pattern of the transfer surface 10A of the stamper 10, and the dividing convex part 44A is formed in a part of the concave part of the basic uneven pattern. The irregular concavo-convex pattern in which at least part of the concave portion of the concavo-convex pattern is divided is drawn so as to expose the portion corresponding to the concave portion, and the exposed portion of the resin layer 44 is removed by development to form the irregular concavo-convex pattern. Processing and etching the resin layer 44 while etching the mask layer 43 to remove at least a part of the portion corresponding to the dividing convex portion 44A to make the mask layer 43 a basic concavo-convex pattern or an irregular concavo-convex pattern. The substrate 42 is processed into a concavo-convex pattern close to the concavo-convex pattern, and the substrate 42 is etched based on the mask layer 43, thereby making the substrate 42 a basic concavo-convex pattern or an irregular pattern. It can be processed with high accuracy pattern closer to convex pattern essentially convex pattern.

  Next, a method for manufacturing the magnetic recording medium 12 using the stamper 10 will be described along the flowchart shown in FIG.

  First, as shown in FIG. 17, an antiferromagnetic layer 34, a soft magnetic layer 36, an orientation layer 38, a (raw unprocessed) recording layer 14, a first mask layer 52, and a second layer are formed on a substrate 26. The magnetic recording medium processing starting body 58 in which the mask layer 54 and the resin layer 56 are formed in this order is prepared, and the stamper 10 is brought into contact with the resin layer 56 to transfer the uneven pattern on the transfer surface 10A to the resin layer 56. To do. On the resin layer 56, a concavo-convex pattern having a concavo-convex positional relationship opposite to the concavo-convex pattern on the transfer surface 10A of the stamper 10 is formed (S120). The concave / convex pattern transferred to the resin layer 56 has the same concave / convex positional relationship as the concave / convex pattern of the master 40. For example, C (carbon) can be used as the material of the first mask layer 52, and Ni can be used as the material of the second mask layer 54, for example. Further, as the material of the resin layer 56, a resist material or the like can be used.

Next, the resin layer 56 is uniformly etched by reactive ion etching using O ₂ or O ₃ gas so that the portion constituting the bottom of the recess in the resin layer 56 is removed, and the second bottom is formed on the bottom of the recess. The mask layer 54 is exposed (S122). The portion of the servo area SA of the resin layer 56 is processed into a basic concavo-convex pattern as shown in FIG. 11 or a concavo-convex pattern in which the irregular concavo-convex pattern is close to the basic concavo-convex pattern.

Next, the second mask layer 54 is etched by ion beam etching using Ar gas using the resin layer 56 as a mask (S124), and the first mask at the bottom of the recess is formed by reactive ion etching using SF ₆ gas. The layer 22 is removed (S126), and the recording layer 14 at the bottom of the recess is removed by ion beam etching using Ar gas (S128), and the recording layer 14 is processed into a concavo-convex pattern as shown in FIGS. To do. As shown in FIGS. 5 and 6, the servo area SA of the recording layer 14 is processed into a basic concavo-convex pattern or a concavo-convex pattern in which the irregular concavo-convex pattern is close to the basic concavo-convex pattern.

  Next, a filling material 28 is formed on the recording layer 14 by bias sputtering to fill the recesses (S130), and Ar gas is irradiated from a direction inclined with respect to the surface of the recording layer 14 by ion beam etching. Then, the surplus filler 28 is removed and the surface is flattened (S132).

  Next, the protective layer 30 is formed on the upper surfaces of the recording layer 14 and the filler 28 by the CVD method (S134), and further the lubricating layer 32 is formed on the protective layer 30 by the dipping method (S136). Thereby, the magnetic recording medium 12 is completed.

  In the magnetic recording medium 12, the servo area SA of the recording layer 14 is formed with a concavo-convex pattern corresponding to servo information, so that servo information is efficiently and reliably recorded by applying a DC magnetic field. More specifically, when each convex portion of the servo area SA is magnetized in a predetermined direction perpendicular to the surface, information on either 0 or 1 is recorded, and each concave portion is not magnetized, Is recorded.

  It is possible that the dividing projection 44A of the resin layer 44 may not be completely removed in the mask layer etching step (S108). In such a case, the recording layer 14 may be processed into a concavo-convex pattern in which the concave portion is partially divided with respect to the desired concavo-convex pattern, but in the vicinity of the boundary of the continuous concave unit region CU. If the resin layer 44 is processed into an irregular concavo-convex pattern in which the dividing convex portions 44A are formed, the concave portions of the recording layer 14 are processed so as to be divided into grid-like regions that divide the servo regions SA. Therefore, the magnetic head can easily recognize each square area accurately. Further, since the magnetic head flies relatively in the circumferential direction Dc with respect to the magnetic recording medium 12, an irregular concavo-convex pattern in which the dividing convex portion 44A is formed in the vicinity of the boundary of the concave unit region CU continuous in the radial direction Dr. If the resin layer 44 is processed, the influence on the servo signal reading is small. In other words, the resin layer 44 is preferably processed into an irregular concavo-convex pattern in which the concave portions of the basic concavo-convex pattern are divided in the radial direction Dr with respect to the basic concavo-convex pattern.

  Next, a second embodiment of the present invention will be described.

  The master 40 according to the first embodiment is configured to include a substrate 42 having one surface processed into a concavo-convex pattern and a mask layer 43 formed on the convex portion of the substrate 42, whereas As shown in FIG. 18, the master 60 according to the second embodiment is characterized in that it includes a substrate 62 having flat surfaces and a resin layer 64 formed in a concavo-convex pattern on the substrate 62. . In the manufacturing process of the master 60, no mask layer is formed between the substrate 62 and the resin layer 64, and the mask layer processing step (S108) and the substrate processing step (S110) are omitted, while FIG. As shown in the flowchart, a resin layer etching step (S204) is provided between the developing step (S106) and the conductive film forming step (S112). Since the other points are the same as those in the first embodiment, description thereof will be omitted as appropriate.

  A method for producing the master 60 will be specifically described. First, a master disk processing starting body in which the resin layer 64 is formed on the substrate 62 with a uniform thickness is produced (S202). Next, as in the first embodiment, the exposure step (S104) and the development step (S106) are executed to process the resin layer 64 into an irregular concavo-convex pattern.

Next, the resin layer 64 is etched, and the projections 64A for separation among the projections of the resin layer 64 are selectively removed, so that the basic concavo-convex pattern or the irregular concavo-convex pattern is brought close to the basic concavo-convex pattern. The resin layer 64 is processed (S204). As a specific etching method, reactive ion etching using O ₂ or O ₃ gas as a reactive gas, ion beam etching using Ar gas, O ₂ or O ₃ gas, or the like can be used. As a result, the master 60 shown in FIG. 18 is obtained.

  The stamper 10 is obtained by performing the conductive film forming step (S112) and the electrolytic plating step (S114) on the master 60 obtained in this manner, as in the first embodiment. In the second embodiment, similarly to the first embodiment, a concavo-convex pattern in which the basic concavo-convex pattern or the irregular concavo-convex pattern is brought close to the basic concavo-convex pattern on the transfer surface 10A of the stamper 10 can be formed with high accuracy.

  Next, a third embodiment of the present invention will be described.

  The irregular concavo-convex pattern according to the first embodiment is different from the basic concavo-convex pattern in that the division concavo-convex portion 44A is formed in a part of the concave portion of the basic concavo-convex pattern and the concave portion of the basic concavo-convex pattern is divided. As shown in FIG. 20, the irregular concavo-convex pattern according to the third embodiment is different from the basic concavo-convex pattern in the corner portion of the convex portion protruding toward the adjacent concave portion. At least a part of the pattern is a concavo-convex pattern including a protrusion 44 </ b> B that protrudes toward the concave part adjacent to the corner part of the basic concavo-convex pattern corresponding to the corner part. Since the other points are the same as those in the first embodiment, description thereof will be omitted as appropriate.

  Similar to the first embodiment, the resin layer 44 has a concavo-convex pattern corresponding to the irregular concavo-convex pattern by executing the processing starting body preparation step (S102), the exposure step (S104), and the development step (S106). Processed.

  Next, when the mask layer 43 is etched (S108), the resin layer 44 is also etched, and the protrusions 44B of the resin layer 44 are processed faster than other portions of the resin layer 44, and the corners where the protrusions 44B are formed. The part is processed into a shape close to the corner of the basic concavo-convex pattern corresponding to this corner. That is, the resin layer 44 is processed into a concavo-convex pattern in which the basic concavo-convex pattern or the irregular concavo-convex pattern is close to the basic concavo-convex pattern. Accordingly, the mask layer 43 is also processed into a concavo-convex pattern in which the basic concavo-convex pattern or the irregular concavo-convex pattern is close to the basic concavo-convex pattern. In order to process the resin layer 44 into a concavo-convex pattern close to the basic concavo-convex pattern, it is preferable that the inner angle of the protrusion 44B is an acute angle.

  Further, by etching the substrate 42 (S110), the substrate 42 is also processed into a concavo-convex pattern in which the basic concavo-convex pattern or the irregular concavo-convex pattern is brought close to the basic concavo-convex pattern.

  The stamper 10 is obtained by performing the conductive film forming step (S112) and the electrolytic plating step (S114) on the master 40 thus obtained in the same manner as in the first embodiment. In the third embodiment, similarly to the first embodiment, a concavo-convex pattern in which a basic concavo-convex pattern or an irregular concavo-convex pattern is brought close to the basic concavo-convex pattern on the transfer surface 10A of the stamper 10 can be formed with high accuracy.

  Next, a fourth embodiment of the present invention will be described.

  In the fourth embodiment, an irregular concavo-convex pattern is used as the concavo-convex pattern shown in FIG. 20 of the third embodiment as compared to the second embodiment. Since the other points are the same as those in the first to third embodiments, description thereof will be omitted as appropriate. In the fourth embodiment, similarly to the first to third embodiments, a concavo-convex pattern in which a basic concavo-convex pattern or an irregular concavo-convex pattern is close to the basic concavo-convex pattern is formed on the transfer surface 10A of the stamper 10 with high accuracy. it can.

  In the first to fourth embodiments, the concavo-convex pattern shown in FIGS. 5 and 6 is exemplified as the concavo-convex pattern of the servo area SA of the recording layer 14, and the basic concavo-convex pattern of the resin layer 44 corresponding to this is illustrated. As the irregular concavo-convex pattern, in the first and second embodiments, the basic concavo-convex pattern shown in FIG. 11 and the irregular concavo-convex pattern shown in FIG. 12 are exemplified, and the third and fourth are shown. In the embodiment, the irregular concavo-convex pattern shown in FIG. 20 is illustrated, but the basic concavo-convex pattern and the irregular concavo-convex pattern may be appropriately determined according to the performance required for the magnetic recording medium 12.

  For example, FIG. 4 illustrates servo information composed of a preamble part 16, a SAM part 18, a track address signal part 20, a sector address signal part 22, and a burst signal part 24, but servo information is required. Depending on the performance, etc., some of these may be replaced, or some of these may be omitted, or other parts may be added to perform basic functions. What is necessary is just to determine a target uneven | corrugated pattern suitably according to such servo information.

  Further, the grid-like area that divides the servo area SA is not limited to a square or a rectangle having a right inner angle, and may be a parallelogram. Therefore, the shape of the concave unit region CU and the protruding unit region PU is not limited to a square or a rectangle, and may be a parallelogram.

  Further, in FIG. 12 of the first and second embodiments, the irregular concavo-convex pattern of the resin layer 44 is formed with dividing convex portions 44A at the boundaries of all the continuous concave unit regions CU in the basic concavo-convex pattern. The concave / convex pattern is formed by dividing all the concave portions. However, if a basic concave / convex pattern or a desired concave / convex pattern close to the basic concave / convex pattern can be formed on the masters 40 and 60, a part of the continuous concave / convex pattern in the basic concave / convex pattern can be formed. The resin layer 44 may be processed into an irregular concavo-convex pattern formed by forming the division convex portions 44A at the boundaries of the concave unit regions CU and dividing the concave portions of some of the concave unit regions CU.

  Further, in FIG. 12 of the first and second embodiments, the irregular concavo-convex pattern of the resin layer 44 is such that the dividing ridge 44A is formed at the boundary of the continuous dent unit region CU in the basic concavo-convex pattern shown in FIG. If the concave / convex pattern is formed and the concave / convex pattern of the basic concave / convex pattern is divided, if the basic concave / convex pattern or a desired concave / convex pattern close to the basic concave / convex pattern can be formed on the masters 40 and 60, the boundary in the concave unit region CU The resin layer may be processed into an irregular concavo-convex pattern in which the convex portions for division are formed in other portions other than the vicinity and the concave portions of the basic concavo-convex pattern are divided. Furthermore, if a basic concavo-convex pattern or a desired concavo-convex pattern close to the basic concavo-convex pattern can be formed on the masters 40, 60, the resin layer is processed into an irregular concavo-convex pattern in which the concave portions of the basic concavo-convex pattern are divided in the circumferential direction Dc. May be.

  In the first and third embodiments, when the mask layer 43 is etched using the resin layer 44 as a mask, the resin layer 44 is processed into a concavo-convex pattern in which the irregular concavo-convex pattern is close to the basic concavo-convex pattern. The mask layer 43 is processed into a concavo-convex pattern that approximates the basic concavo-convex pattern to the basic concavo-convex pattern. A resin layer etching step is provided between the development step (S106) and the mask layer etching step (S108). The resin layer 44 may be processed into a concavo-convex pattern in which the irregular concavo-convex pattern is close to the basic concavo-convex pattern.

  Further, even after the mask layer etching step (S108), the portion corresponding to the dividing convex portion 44A of the resin layer 44 and the portion corresponding to the dividing convex portion 44A in the mask layer 43 may remain without being completely removed. In such a case, the dividing projections 44A of the resin layer 44 and the projections of the mask layer 43 corresponding thereto may be removed in the substrate etching step (S110).

  In the first and third embodiments, the mask layer 43 and the resin layer 44 are formed on the substrate 42, and the substrate 42 is indirectly processed into a concavo-convex pattern based on the concavo-convex pattern resin layer 44. However, as long as a basic uneven pattern or a desired uneven pattern close to the basic uneven pattern can be formed on the master 40, the material, thickness, and number of layers of the mask layer are not particularly limited, and 2 between the substrate and the resin layer. It is also possible to provide a mask layer that is equal to or more than one layer, and to process these into an uneven pattern in sequence. Alternatively, the mask layer may be omitted, and a resin layer may be formed directly on the substrate, and the substrate may be processed directly into an uneven pattern based on the resin layer.

  In the first and third embodiments, the substrate 42 is processed into a concavo-convex pattern as the resin layer support material. However, a resin layer support material different from the substrate is provided on the substrate, and the resin layer support material The resin layer is directly or indirectly formed through a mask layer or the like, and the resin layer support material is processed into a concavo-convex pattern directly or indirectly (without processing the substrate) based on the concavo-convex pattern resin layer. May be.

  In the first and third embodiments, the master 40 includes the substrate 42 and the mask layer 43 formed on the convex portion of the substrate 42, but is a substrate that is a resin layer support material. Or after processing the resin layer support material provided on the board | substrate into the uneven | corrugated pattern, you may use what removed the mask layer as an original disk.

  Further, in the first embodiment, the substrate 42 is etched so as to form a concave portion continuous with the portion corresponding to the dividing convex portion 44A, and in the second embodiment, the portion corresponding to the dividing convex portion 44A is formed. The resin layer 44 is etched so as to form a continuous concave portion. If the magnetic head can reliably recognize 0 or 1 information of the magnetic recording medium, for example, a slight convex portion is formed on the portion corresponding to the dividing convex portion 44A. The substrate 42 or the resin layer 44 may be processed into a concavo-convex pattern close to a basic concavo-convex pattern such as a concavo-convex pattern in which a portion is formed.

  In FIG. 20 of the third and fourth embodiments, the irregular uneven pattern of the resin layer 44 is a basic unevenness in which all the corners of the protrusions protruding toward the adjacent recesses correspond to the corners. A concave / convex pattern including a protrusion 44B protruding from the corner portion of the pattern toward the adjacent concave portion, but if the basic concave / convex pattern or a desired concave / convex pattern close to the basic concave / convex pattern can be formed on the masters 40 and 60, the adjacent concave portion Resin layer having an irregular concavo-convex pattern in which only a part of the corners of the convex part projecting to the side includes a projecting part projecting to the concave part adjacent to the corner part of the basic concavo-convex pattern corresponding to the corner part 44 may be processed.

  In the first and second embodiments, the irregular concavo-convex pattern of the resin layer 44 is a concavo-convex pattern obtained by dividing the concave portion of the basic concavo-convex pattern. In the third and fourth embodiments, the resin layer The irregular irregular pattern of 44 is an irregular pattern in which a corner portion of a convex portion protruding toward the adjacent concave portion includes a protrusion portion protruding toward the concave portion adjacent to the corner portion of the basic concave / convex pattern corresponding to the corner portion. However, by combining these, a part of the concave part of the basic concave / convex pattern is divided with respect to the basic concave / convex pattern, and only a part of the corners of the convex part protruding to the adjacent concave part side The resin layer 44 may be processed into an irregular concavo-convex pattern including a protrusion protruding toward the concave portion adjacent to the corner portion of the basic concavo-convex pattern corresponding to the corner portion.

  12 of the first and second embodiments and FIG. 20 of the third and fourth embodiments are enlarged portions corresponding to the track address signal portion 20 of the servo area SA in the resin layer 44. FIG. However, the region where the resin layer is processed into an irregular concavo-convex pattern may be the entire portion corresponding to the servo region SA, and is limited to a portion corresponding to a fine and complicated region such as the track address signal portion 20. May be.

  In the first embodiment, the processing starting body 58 of the magnetic recording medium has a configuration in which the first mask layer 52, the second mask layer 54, and the resin layer 56 are formed on the recording layer 14. The recording layer 14 is processed by sequentially etching these. However, the material, thickness, and number of layers of the mask layer between the recording layer and the resin layer are not particularly limited as long as the recording layer can be processed with high accuracy. For example, the mask layer between the recording layer and the resin layer may be one layer or three or more layers, or the resin layer may be directly formed on the recording layer.

  In the first to fourth embodiments, the stamper 10 is manufactured by forming the conductive film 48 and the electrolytic plating layer 50 on the masters 40 and 60 and peeling them together. Alternatively, the electroplating layer 50 may be used as a metal master, and the stamper may be formed from the metal master by an electrolytic plating method. By doing in this way, the stamper whose uneven | corrugated pattern and the uneven | corrugated positional relationship of the original disk 40 correspond is obtained. Further, the metal master and the stamper may be manufactured by repeating the electrolytic plating method.

  In the first to fourth embodiments, the material of the conductive film 48 is Ni. However, as the material of the conductive film, other conductive materials such as Ag, Au, and Cu may be used.

  Further, in the first to fourth embodiments, the material of the electrolytic plating layer 50 is also Ni. However, if the material has appropriate hardness and ductility as a stamper or a metal master, For example, other materials such as a Ni—Co (cobalt) alloy may be used.

  In the first and third embodiments, the stamper 10 including the conductive film 48 and the electrolytic plating layer 50 is performed on the master 40 by performing the conductive film deposition step (S112) and the electrolytic plating step (S114). However, the conductive film forming step (S112) may be omitted by using a conductive material as the material of the master substrate (resin layer support material). In this case, a stamper or a metal master that does not include a conductive film and includes only an electrolytic plating layer is obtained.

  In the first to fourth embodiments, the magnetic recording medium 12 is filled with the filler 28 in the concave portions between the convex portions of the recording layer 14. The present invention can also be applied to the manufacture of a magnetic recording medium having an unfilled configuration.

  In the first to fourth embodiments, the magnetic recording medium 12 is a discrete track medium in which the data area DA of the recording layer 14 is divided into a large number of recording elements 14A at fine intervals in the radial direction Dr. However, a patterned medium in which the data area DA of the recording layer is divided into a large number of recording elements at fine intervals in the radial direction Dr and the circumferential direction Dc, and the data area DA of the recording layer has a uniform thickness. The present invention can also be applied to the production of a continuous film-shaped magnetic recording medium.

  In the first to fourth embodiments, the magnetic recording medium 12 is a perpendicular recording type. However, the present invention can also be applied to manufacture an in-plane recording type magnetic recording medium.

  The first to fourth embodiments relate to the manufacture of the magnetic recording medium 12, but the present invention is also applicable to the manufacture of other information recording media such as optical recording media and semiconductors. is there.

  The present invention can be used, for example, for manufacturing a stamper used for forming a concavo-convex pattern in a manufacturing process of a semiconductor product or an information recording medium.

1 is a side sectional view schematically showing the structure of a stamper according to a first embodiment of the present invention. A plan view schematically showing the uneven pattern on the transfer surface of the stamper A plan view schematically showing the structure of a magnetic recording medium manufactured using the stamper A plan view schematically showing an enlarged servo area of the magnetic recording medium A plan view schematically showing an enlarged track address part of the servo area A plan view schematically showing the track address portion further enlarged. Side sectional view schematically showing the structure of the magnetic recording medium Flow chart showing an outline of the stamper manufacturing process Side sectional view schematically showing the structure of the master produced in the stamper manufacturing process Side sectional view schematically showing the structure of the starting material for the same master The top view which shows typically the basic uneven pattern of the resin layer of the same master A plan view schematically showing an irregular uneven pattern of the resin layer Side sectional view schematically showing a state in which the resin layer is processed into a concavo-convex pattern Side sectional view schematically showing a state in which the mask layer is processed into a concavo-convex pattern Side sectional view schematically showing a master on which a conductive film and an electrolytic plating layer are formed Flow chart showing an outline of the manufacturing process of the magnetic recording medium Side sectional view schematically showing an imprint process by the stamper Side sectional view which shows typically the structure of the master of the stamper which concerns on 2nd Embodiment of this invention Flow chart showing the outline of the stamper manufacturing process The top view which shows typically the irregular uneven | corrugated pattern of the resin layer of the original disk which concerns on 3rd Embodiment and 4th Embodiment of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Stamper 10A ... Transfer surface 12 ... Magnetic recording medium 14 ... Recording layer 14A ... Recording element 16 ... Preamble part 18 ... SAM part 20 ... Track address part 22 ... Sector address signal part 24 ... Burst signal part 26 ... Substrate 28 ... Filling Material 30 ... Protective layer 32 ... Lubricating layer 34 ... Antiferromagnetic layer 36 ... Soft magnetic layer 38 ... Orientation layer 40, 60 ... Master disk 42, 62 ... Substrate (resin layer support material)
44, 64 ... Resin layer 44A ... Dividing convex part 44B ... Protruding part 45 ... Master disk processing body 48 ... Conductive film 50 ... Electrolytic plating layer 52 ... First mask layer 54 ... Second mask layer 56 ... Resin layer 58 ... Processing start body of magnetic recording medium DA ... Data area SA ... Servo area CU ... Concave unit area PU ... Convex unit area Dr ... Radial direction Dc ... Circumferential direction S102, S202 ... Master processing start body preparation step S104 ... Exposure Step S106 ... Development step S108 ... Mask layer etching step S110 ... Substrate etching step S112 ... Conductive film forming step S114 ... Electroplating step S120 ... Imprint step S122 ... Resin layer etching step S124 ... Second mask layer etching step S126 ... First mask layer etching step S128 ... Recording layer etching step S130 ... Filler film forming process Step S132: Planarization step S134 ... Protective layer forming step S136 ... Lubricating layer forming step S204 ... Resin layer etching step

Claims (15)

  The resin layer formed on the resin layer support material is divided into a concave portion of the basic concavo-convex pattern by forming a dividing convex portion in a part of the concave portion of the basic concavo-convex pattern with respect to a predetermined basic concavo-convex pattern. An irregular concavo-convex pattern forming step for processing into an irregular concavo-convex pattern divided at least in part, and etching the resin layer support material based on the resin layer to bring the irregular concavo-convex pattern closer to the basic concavo-convex pattern And a resin layer support material etching step for processing the resin layer support material into a concavo-convex pattern having a different shape. In claim 1,
Resin layer etching step of selectively removing the projections for division among the projections of the resin layer by etching the resin layer between the irregular pattern forming step and the resin layer support material etching step A method for manufacturing a master, characterized in that In claim 1 or 2,
A mask layer that functions as a mask for etching in the resin layer support material etching step is formed between the resin layer support material and the resin layer, and the irregular concavo-convex pattern forming step and the resin layer support material etching step And a mask layer etching step of etching the mask layer based on the resin layer while removing the dividing protrusions of the resin layer. In any one of Claims 1 thru | or 3,
In the resin layer support material etching step, the resin layer support material is etched so as to form a continuous concave portion under the dividing convex portion.   The resin layer formed on the resin layer support material is divided into a concave portion of the basic concavo-convex pattern by forming a dividing convex portion in a part of the concave portion of the basic concavo-convex pattern with respect to a predetermined basic concavo-convex pattern. An irregular concavo-convex pattern forming step for processing into an irregular concavo-convex pattern at least partially divided, and the resin into a concavo-convex pattern in a form in which the irregular concavo-convex pattern is brought close to the basic concavo-convex pattern by etching the resin layer And a resin layer etching step for processing the layer. In claim 5,
In the resin layer etching step, the resin layer is etched so as to selectively remove the dividing projections among the projections of the resin layer. In any one of Claims 1 thru | or 6.
The concave / convex pattern of the master is divided into a plurality of data areas and a plurality of servo areas, and each servo area is further divided into a plurality of grid-like areas. Information is binary-recorded on the recording layer according to a predetermined rule, and the recording layer uses the servo area portion as either one of the 0 and 1 information in the grid-like area. Is a concavo-convex pattern corresponding to the concavo-convex pattern of the recording layer of the magnetic recording medium formed by the concavo-convex pattern in which the area where the information is recorded is a concave and the other information is recorded is a convex.
In the basic concavo-convex pattern, a portion corresponding to the grid-like region in which any one of the information of 0 and 1 is recorded is a concave unit region among the grid-like regions of the servo region of the recording layer. The portion corresponding to the grid-like region in which the other information is recorded is a concavo-convex pattern that is a convex unit region, and in the irregular concavo-convex pattern forming step, the resin layer is compared with the basic concavo-convex pattern, The resin layer is formed into an irregular concavo-convex pattern in which the dividing convex portion is formed in the vicinity of a boundary between at least two continuous concave portion unit regions among the concave unit regions, and the concave portions divided into the continuous concave unit regions are formed. A method of manufacturing a master, characterized by processing the material. In claim 7,
The irregular concavo-convex pattern has the dividing convex portions formed in the vicinity of a boundary between at least two concave unit units continuous in the radial direction of the magnetic recording medium among the concave unit regions of the basic concavo-convex pattern. A method for manufacturing a master, which is a concavo-convex pattern in which concave portions divided in the radial direction are formed in a concave unit area. In any one of Claims 1 thru | or 8.
In the irregular concavo-convex pattern forming step, the resin layer is formed of the basic concavo-convex pattern in which at least a part of a corner of a convex portion protruding from an adjacent concave portion corresponds to the basic concavo-convex pattern. A method of manufacturing a master, which is processed into an irregular concavo-convex pattern including a protruding portion that protrudes toward a concave portion adjacent to a corner portion.   The basic concavo-convex pattern in which at least a part of the corners of the convex portion protruding from the adjacent concave portion corresponds to the corner portion of the resin layer formed on the resin layer support material with respect to a predetermined basic concavo-convex pattern. An irregular concavo-convex pattern forming step including a protrusion protruding toward the concave portion adjacent to the corner of the substrate, and the irregular concavo-convex pattern formed by etching the resin layer support material based on the resin layer. And a resin layer support material etching step for processing the resin layer support material into a concavo-convex pattern having a pattern close to the basic concavo-convex pattern.   The basic concavo-convex pattern in which at least a part of the corners of the convex portion protruding from the adjacent concave portion corresponds to the corner portion of the resin layer formed on the resin layer support material with respect to a predetermined basic concavo-convex pattern. An irregular concavo-convex pattern forming step including a protrusion protruding toward the concave portion adjacent to the corner of the irregular concavo-convex pattern; and etching the resin layer to convert the irregular concavo-convex pattern into the basic concavo-convex pattern And a resin layer etching step of processing the resin layer into a concavo-convex pattern in a close form. In any one of Claims 1 thru | or 11,
A method of manufacturing a master, wherein a resist material is used as a material of the resin layer, and the resin layer is processed into the irregular concavo-convex pattern by exposure and development in the irregular concavo-convex pattern forming step.   A stamper manufacturing method comprising an electrolytic plating step of forming an electrolytic plating layer by an electrolytic plating method on a master manufactured by the master manufacturing method according to any one of claims 1 to 12. In claim 13,
The electrolytic plating process is a first electrolytic plating process, and after the first electrolytic plating process, a peeling process of peeling the metal master including the electrolytic plating layer from the master, and an electrolytic plating method on the metal master. And a second electrolytic plating process for forming either the stamper or another metal master.   A method for manufacturing a magnetic recording medium, comprising the step of transferring a concavo-convex pattern corresponding to the concavo-convex pattern of the recording layer using the stamper manufactured by the method for manufacturing a stamper according to claim 13 or 14.

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