JP4189600B2 - Manufacturing method of magnetic transfer master disk - Google Patents

Description

  The present invention relates to a substrate manufacturing method, and more particularly, to a substrate used for manufacturing a magnetic transfer master disk suitable for magnetically transferring a magnetic information pattern such as format information to a magnetic disk used in a hard disk device or the like. It relates to the manufacturing method.

  In recent years, magnetic disks (hard disks) used in hard disk drives, which have been rapidly spreading, are written with format information and address information before being installed in the drive after being delivered to the drive manufacturer by the magnetic disk manufacturer. It is common. Although this writing can be performed by a magnetic head, a method of batch transfer from a master disk in which these format information and address information are written is efficient and preferable.

  Such magnetic transfer includes a master disk (patterned master) having a magnetic layer on the surface and having a transfer pattern such as a servo signal formed in an uneven shape, and a magnetic recording unit such as a hard disk or a flexible disk. This is done by applying a magnetic field for transfer to these close contact members in close contact with the disk for use (slave disk) and transferring and recording a magnetization pattern corresponding to the information carried on the master disk onto the slave disk.

  As a master disk used for the magnetic transfer, for example, in Patent Document 1, an uneven pattern corresponding to an information signal is formed on the surface of a substrate, and a thin magnetic layer is formed on the surface of the uneven pattern. What has been proposed.

  This master disk is manufactured, for example, by the following process. First, an electron beam resist or a photoresist is applied on a Si substrate having a flat surface, a transfer pattern is drawn and exposed by an electron beam or light, and developed to form a coating pattern for photoetching with the resist. Then, the Si substrate is etched to obtain a master having an uneven pattern. Thereafter, the resist is peeled off.

Next, a conductive layer is provided on the concavo-convex pattern of the master, for example, by sputtering, the master on which the conductive layer is provided is immersed in an electrolytic solution, and Ni is electrodeposited on the conductive layer to form a metal plate having a predetermined thickness. (Reversing board) is formed. Then, the metal plate is peeled off from the master, and the peeled metal plate is punched out to a predetermined size to produce a master substrate, and a magnetic layer is formed on the uneven pattern surface of the master substrate. As a result, a magnetic transfer master disk is manufactured.
JP 2001-256644 A

  However, when the Si substrate is etched, the planar size of the resist opening (the uneven pattern size of the master substrate) also changes in one substrate (for example, the line width is several tens nm to several μm). This often causes variations in the etching depth. When the etching depth varies as described above, the pattern height of the concavo-convex pattern of the master substrate formed by transferring from the substrate varies, and the performance of the master substrate is inferior. .

  The present invention has been made in view of such circumstances, and in manufacturing a magnetic transfer master disk, the etching depth of the substrate does not vary and, as a result, the transfer accuracy is improved. An object of the present invention is to provide a method for manufacturing a substrate used for manufacturing the substrate.

To achieve the above object, the present invention provides a manufacturing method of a large number of fine irregularities shaped master disk for magnetic transfer magnetic layer pattern is formed on the surface, the etching selectivity to the flat surface of the wafer Ri Ah at greater than resist agent, and a work layer forming step of etching selection ratio to form a processed layer of Ah Ru member larger than the wafer, the resist agent to the surface of the layer to be processed is applied, the A resist coating step for forming a layer of the resist agent, a drawing exposure to the layer of the resist agent, and a resist patterning step for forming an opening of the layer of the resist agent on the surface of the layer to be processed by a subsequent development process; , wherein the opening of the layer of resist material and etching to remove any layer to be processed in the thickness direction from the surface to remove the layer of resist material, uneven pattern is formed based on A reversing plate forming step of forming a reversing plate made of a metal plate having a predetermined thickness by electrodepositing a metal on the surface of the substrate on which the concavo-convex pattern is formed, and the reversing from the substrate. A peeling step of peeling a plate and obtaining a master substrate having a reverse pattern of the uneven pattern on its surface; and a step of forming a magnetic layer on the surface of the uneven pattern of the master substrate. A method for manufacturing a magnetic transfer master disk is provided.

  According to the present invention, since the etching selectivity of the layer to be processed is larger than that of the resist agent, the etching depth of the layer to be processed can be sufficiently ensured before the resist agent is removed by the etchant, and the etching depth of the substrate can be secured. Is less likely to cause variations. As a result, a substrate used for manufacturing a magnetic transfer master disk with good transfer accuracy can be obtained.

  Note that the etching selectivity means the ratio of the degree of removal by the etchant. The etching selectivity of the layer to be processed is larger than that of the resist agent. Under the same etching conditions, the etching rate of the layer to be processed is It is larger than the etching rate of the resist agent.

  In this invention, it is preferable that the etching selectivity of the said to-be-processed layer is 2 or more with respect to a resist agent. Thus, if the etching selectivity of the layer to be processed is 2 or more with respect to the resist agent, the etching depth of the layer to be processed can be sufficiently secured. In that sense, the etching selectivity of the layer to be processed is more preferably 3 or more with respect to the resist agent, and further preferably 5 or more.

  Moreover, in this invention, it is preferable to form the said to-be-processed layer by either the physical vapor deposition method, the chemical vapor deposition method, and the thermal oxidation method. Many layers to be processed formed by PVD, CVD, or thermal oxidation are suitable for the present invention because their etching selectivity is larger than that of the resist agent.

  In the present invention, the layer to be processed is preferably an oxide of Si or a nitride of Si, and the wafer is preferably Si. If the layer to be processed is an oxide of Si or a nitride of Si, it is suitable for the present invention because there are many etching selectivity ratios with respect to the resist agent, and the Si substrate (wafer) is photolithography. Since it is easy to form a fine concavo-convex pattern by, for example, it is suitable for the present invention.

  Further, the present invention provides a method for manufacturing a substrate for a magnetic transfer master disk having a large number of fine uneven magnetic layer patterns formed on a surface thereof, wherein the etching selectivity is higher on the flat surface of the wafer than that of the wafer. A coating layer forming step for forming a coating layer of a certain member; a resist agent applied to the surface of the coating layer; a resist coating step for forming the resist agent layer; and a drawing exposure on the layer of the resist agent; A resist patterning step of forming openings of the resist agent layer on the surface of the coating layer by subsequent development processing, and removing all the covering layers of the openings of the resist agent layer in the thickness direction from the surface, An etching process for forming an opening of the coating layer on the surface of the wafer, and an ashing process for removing the resist agent layer. To provide a production method.

  According to the present invention, since the coating layer etching selectivity is larger than that of the wafer, even if the coating layer is completely removed from the surface in the thickness direction by etching, the etching rate of the wafer is slow and the etching depth of the coating layer is reduced. It is difficult to cause variations in the thickness. As a result, a substrate used for manufacturing a magnetic transfer master disk with good transfer accuracy can be obtained.

  The etching selectivity is the same as the definition described above. The coating layer etching selectivity is larger than that of the wafer. Under the same etching conditions, the etching rate of the coating layer is larger than the etching rate of the wafer. That is.

  In this invention, it is preferable that the etching selectivity of the said coating layer is 50 or more with respect to the said wafer. Thus, if the etching selectivity of the coating layer is 50 or more with respect to the wafer, the etching depth of the coating layer can be sufficiently secured. In that sense, the etching selectivity of the layer to be processed is more preferably 100 or more and further preferably 150 or more with respect to the wafer.

  Further, the present invention provides a method for manufacturing a substrate for a master disk for magnetic transfer in which a large number of fine uneven magnetic layer patterns are formed on the surface, and the etching selectivity is lower on the flat surface of the wafer than that of the wafer. Forming a coating layer of a member and forming a pattern layer opening in the coating layer; an etching step of removing the wafer in the opening of the coating layer by a predetermined depth from the surface; and And a coating layer removing step for removing the coating layer.

  According to the present invention, since the etching selectivity of the coating layer is smaller than that of the wafer, even if the wafer is removed in the thickness direction from the surface by etching, the etching speed of the coating layer is slow and the etching depth of the wafer is reduced. Can be sufficiently secured, and variations in the etching depth of the wafer are less likely to occur. As a result, a substrate used for manufacturing a magnetic transfer master disk with good transfer accuracy can be obtained.

  Note that the etching selectivity is the same as the definition described above. The coating layer etching selectivity is smaller than that of the wafer. Under the same etching conditions, the etching rate of the coating layer is smaller than the etching rate of the wafer. That is.

  In addition, as a method for forming a patterned opening in the coating layer, not only a method by photoetching as described later but also various known microfabrication methods such as a method by lift-off using a photoresist can be adopted.

  Further, the present invention provides a method for manufacturing a substrate for a master disk for magnetic transfer in which a large number of fine uneven magnetic layer patterns are formed on the surface, and the etching selectivity is lower on the flat surface of the wafer than that of the wafer. A coating layer forming step for forming a coating layer of a certain member; a resist agent applied to the surface of the coating layer; a resist coating step for forming the resist agent layer; and a drawing exposure on the layer of the resist agent; A resist patterning step of forming openings of the resist agent layer on the surface of the coating layer by subsequent development processing, and removing all the covering layers of the openings of the resist agent layer in the thickness direction from the surface, An opening forming step of forming an opening of the coating layer on the surface of the wafer; an etching step of removing the wafer at the opening of the coating layer by a predetermined depth from the surface; Provides a method for manufacturing a substrate, characterized in that it comprises, ashing step for removing the layer and the coating layer of the serial resist agent.

  According to the present invention, by the resist patterning step and the opening formation step, the covering layer of the opening of the resist agent layer is all removed from the surface in the thickness direction, and the wafer of the covering layer opening is predetermined from the surface. Only the depth is removed by etching. At that time, since the etching selectivity of the coating layer is smaller than that of the wafer, the coating layer functions as an etching mask (etching resist) to ensure a sufficient etching depth of the wafer, and the wafer etching depth varies. Hard to generate. As a result, a substrate used for manufacturing a magnetic transfer master disk with good transfer accuracy can be obtained.

  In this invention, it is preferable that the etching selectivity of the said coating layer is 1/50 or less with respect to the said wafer. Thus, if the etching selectivity of the coating layer is 1/50 or less with respect to the wafer, the etching depth of the wafer can be sufficiently secured. In that sense, the etching selectivity of the coating layer is more preferably 1/100 or less, and even more preferably 1/150 or less with respect to the wafer.

  In the present invention, the coating layer is preferably formed by any one of a physical vapor deposition method, a chemical vapor deposition method, and a thermal oxidation method. As described above, since many layers to be processed formed by PVD, CVD, or thermal oxidation have a small etching selection ratio with respect to the wafer, they are suitable for the present invention.

  In the present invention, it is preferable that the coating layer is Si oxide or Si nitride, and the wafer is Si. If the coating layer is Si oxide or Si nitride, the etching selection ratio is often smaller than that of the wafer, which is suitable for the present invention. The Si substrate (wafer) is obtained by photolithography or the like. Since it is easy to form a fine uneven pattern, it is suitable for the present invention.

As described above, according to the present invention, a master disk for magnetic transfer which transfer accuracy is good can be obtained.

  A preferred embodiment (first embodiment) of a method for producing a substrate used for producing a magnetic transfer master disk according to the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a partially enlarged perspective view of a magnetic transfer master disk manufactured by a method of manufacturing a substrate used for manufacturing a magnetic transfer master disk according to the present invention. FIG. 2 is a plan view of the magnetic transfer master disk. FIG. 3 is a cross-sectional view showing in sequence each step of the substrate manufacturing method used for manufacturing the magnetic transfer master disk according to the present invention. Each figure is a schematic diagram, and is shown in a ratio different from the actual dimensions.

  First, a magnetic transfer master disk manufactured by the substrate manufacturing method according to the present invention will be described. As shown in FIG. 1, the magnetic transfer master disk 10 includes a metal master substrate 12 and a magnetic layer 14, and the master substrate 12 has a fine concavo-convex pattern corresponding to transfer information on the surface. The magnetic layer 14 is coated on the surface.

  In FIG. 1, a transfer information carrying surface is formed on one side of a master substrate 12 where a fine projection pattern is formed by a magnetic layer 14, and the opposite surface of the master substrate 12 is held by an unillustrated contact means. It has become so. The fine protrusion pattern is formed by a photofabrication method to be described later. One surface (transfer information carrying surface) of the master disk 10 is a surface in close contact with the slave disk.

  The fine protrusion pattern is rectangular in plan view, and in the state where the magnetic layer 14 having a thickness m is formed, the length b in the track direction (thick arrow direction in the figure) and the length l in the radial direction. And more. The optimum values of the lengths b and l vary depending on the recording density, the recording signal waveform, and the like. For example, the length b can be 80 nm and the length l can be 200 nm.

  In the case of a servo signal, this fine projection pattern is formed long in the radial direction. In this case, for example, the length l in the radial direction is preferably 0.05 to 20 μm, and the length in the track direction (circumferential direction) is preferably 0.05 to 5 μm. It is preferable to select a pattern having a longer radial direction within this range as a pattern carrying servo signal information.

  The depth of the fine projection pattern (projection height) on the surface of the master substrate 12 is preferably in the range of 20 to 800 nm, and more preferably in the range of 30 to 600 nm.

  In the master disk 10, when the master substrate 12 is made of a ferromagnetic material mainly composed of Ni or the like, magnetic transfer can be performed only with the master substrate 12, and the magnetic layer 14 may not be coated. By providing a good magnetic layer 14, a better magnetic transfer can be performed. When the master substrate 12 is a nonmagnetic material, it is necessary to provide the magnetic layer 14. The magnetic layer 14 of the master disk 10 is preferably a soft magnetic layer having a coercive force Hc of 48 kA / m (≈600 Oe) or less.

  When the master substrate 12 is a ferromagnetic material mainly composed of Ni or the like, it can be produced by electroforming. In this case, as shown in FIG. 2, the master substrate 12 can be formed in a disc shape having a central hole 12a, and an uneven pattern can be formed in the annular region 12b excluding the inner peripheral portion and the outer diameter portion on one side.

  As will be described later, the master substrate 12 is formed by laminating a metal plate having a predetermined thickness by electrodepositing Ni or the like on a master plate on which a concavo-convex pattern corresponding to information is formed, and peeling the metal plate from the master plate. In addition, the outer peripheral portion and the central hole 12a are manufactured by being punched in a desired size.

  Next, the manufacturing method of the master disk 10 is demonstrated based on FIG. 3 (A)-(G). First, as shown in FIG. 3A, a layer to be processed 23 is formed to a predetermined thickness on an original plate 20 that is a silicon wafer having a smooth surface. As a method for forming the layer to be processed 23, various film forming methods including PVD (Physical Vapor Deposition), CVD (Chemical Vapor Deposition), sputtering, and ion plating can be applied.

The layer to be processed 23 is required to have an etching selectivity larger than that of the resist agent (electron beam resist layer 22). As the layer to be processed 23, Si oxide (SiO ₂ ) or Si nitride can be preferably employed.

  Next, as shown in FIG. 3A, a base treatment such as adhesion layer formation is performed on the work layer 23 of the original plate 20 (not shown), and then an electron beam resist solution is applied by spin coating or the like. Application is performed to form a resist layer 22 and a baking process (pre-baking) is performed.

  Next, the original plate 20 is set on the stage of an electron beam exposure apparatus (not shown) equipped with a high-precision rotary stage or XY stage, and the electron beam 24 modulated according to the servo signal while rotating the original plate 20. A predetermined pattern, for example, a pattern corresponding to a servo signal extending linearly in the radial direction from the center of rotation to each track is drawn and exposed on a portion corresponding to each frame on the circumference. To do.

  Next, as shown in FIG. 3B, the resist layer 22 is developed to remove the exposed portion, and a cover layer having a desired thickness is formed by the remaining resist layer 22. This cover layer serves as a mask for the next process (etching process). After the development process, a baking process (post-bake) is performed to increase the adhesion between the resist layer 22 and the original plate 20.

  Next, as shown in FIG. 3C, the processed layer 23 on the original plate 20 is removed (etched) from the surface by a predetermined depth from the opening of the resist layer 22. In this etching, anisotropic etching is desirable to minimize undercut (side etching). As such anisotropic etching, RIE (Reactive Ion Etching) can be preferably employed.

  In the process layer forming step shown in FIG. 3A described above, the process layer 23 is formed thicker than the design removal depth in the etching process. Etching can be terminated at an intermediate point in the thickness direction, and as shown in FIG. 3C, the layer to be processed 23 can be removed (etched) so as to penetrate in the thickness direction.

In the latter case, if the etching condition is set such that the etching selectivity of the layer to be processed (for example, SiO ₂ ) is larger than that of the original plate 20 (for example, Si), the layer to be processed 23 is penetrated in the thickness direction. Even if it is removed in this manner, the surface of the original plate 20 is hardly removed (etched), so that the etching depth is less likely to vary.

Next, as shown in FIG. 3D, the resist layer 22 is removed. As a method for removing the resist layer 22, ashing can be employed as a dry method, and a removal method using a stripping solution can be employed as a wet method. Through the above ashing process, a master 26 on which a reverse type of a desired concavo-convex pattern is formed is produced .

  Next, a conductive layer is formed to a uniform thickness on the surface of the master 26 shown in FIG. As a method for forming the conductive layer, various metal film forming methods including PVD (Physical Vapor Deposition), CVD (Chemical Vapor Deposition), sputtering, and ion plating can be applied. Thus, if the conductive layer is formed, the effect that metal electrodeposition can be performed uniformly is obtained.

  The conductive layer is preferably a film containing Ni as a main component. Such a film containing Ni as a main component is easy to form and is suitable as a conductive layer. Although there is no restriction | limiting in particular as the film thickness of this electrically conductive layer, About tens of nm is generally employable. Since the thickness of the conductive layer is small, the illustration is omitted.

  Next, as shown in FIG. 3E, electrodeposition (electroforming) is performed on the surface of the master 26 to laminate a metal plate made of Ni metal having a desired thickness (reverse plate forming step).

  This electrodeposition is performed by immersing the master 26 in the electrolytic solution of the electroforming apparatus, using the master 26 as an anode, and energizing between the cathode and the electrolyte. At this time, the concentration, pH, and application of the electrolyte are applied. The method is required to be carried out under optimum conditions with no distortion in the laminated metal plates (that is, the master substrate 12).

  Then, after the electrodeposition is completed as described above, the master 26 on which the metal plate (that is, the master substrate 12) is laminated is taken out from the electrolytic solution of the electroforming apparatus and washed with pure water. Next, in the peeling step, the metal plate (that is, the master substrate 12) is peeled from the master 26.

  The master substrate 12 having the concavo-convex pattern inverted from the master 26 as shown in FIG. Then, the inner diameter and the outer diameter of the master substrate 12 are punched into a predetermined size.

  Next, as shown in FIG. 3G, a magnetic layer 14 is formed on the surface of the concavo-convex pattern of the master substrate 12 manufactured as described above by sputtering or the like, and further a protective layer as necessary. The magnetic transfer master disk 10 is manufactured.

  The magnetic layer 14 is formed by applying a magnetic material to a vacuum film forming means such as a vacuum deposition method, a sputtering method or an ion plating method, or a plating method such as electroforming. As the magnetic material of the magnetic layer 14, Co, Co alloy (CoNi, CoNiZr, CoNbTaZr, etc.), Fe, Fe alloy (FeCo, FeCoNi, FeNiMo, FeAlSi, FeAl, FeTaN), Ni, Ni alloy (NiFe) should be used. Can do. Among these, it is particularly preferable to use FeCo or FeCoNi. The thickness m of the magnetic layer 14 is preferably in the range of 50 nm to 500 nm, and more preferably in the range of 50 nm to 300 nm.

  Further, it is preferable to provide a protective film such as diamond-like carbon (DLC) or sputtered carbon on the uneven pattern of the magnetic layer 14, and a lubricant layer may be provided. Further, it is more preferable that a DLC film of 5 to 30 nm and a lubricant layer exist as a protective film. The lubricant improves the deterioration of durability such as the occurrence of scratches due to friction when correcting the deviation caused in the contact process with the slave disk.

  Next, another embodiment (second embodiment) of a method for manufacturing a substrate used for manufacturing a magnetic transfer master disk according to the present invention will be described. In this embodiment, instead of the layer to be processed 23 of the first embodiment described above, a coating layer 25 is formed on the original plate 20, and this coating layer 25 is used as a mask in the etching process. Other processes are the same as those in the first embodiment. Therefore, only different steps will be described in detail.

  First, as shown in FIG. 4A, a coating layer 25 is formed to a predetermined thickness on an original plate 20 that is a silicon wafer having a smooth surface. As a method for forming the covering layer 25, various film forming methods including PVD (Physical Vapor Deposition), CVD (Chemical Vapor Deposition), sputtering, and ion plating can be applied.

The coating layer 25 is required to have an etching selection ratio larger than that of the resist agent (electron beam resist layer 22) and to be smaller than that of the original plate 20. As such a covering layer 25, when the original plate 20 is a Si wafer, Si oxide (SiO ₂ ) or Si nitride can be preferably employed.

  Next, as shown in FIG. 4 (A), a base treatment (formation of an adhesion layer not shown) on the coating layer 25 of the original plate 20, formation of a resist layer 22 by applying an electron beam resist solution, and baking treatment (Pre-baking) and a process of drawing and exposing a pattern corresponding to a servo signal by an electron beam exposure apparatus (not shown) are substantially the same as those in FIG.

  Next, as shown in FIG. 4B, the resist layer 22 is developed to remove the exposed portion, and a cover layer having a desired thickness is formed by the remaining resist layer 22. This cover layer serves as a mask when the coating layer 25 is etched. After the development process, a baking process (post-bake) is performed to increase the adhesion between the resist layer 22 and the original plate 20.

  Next, as shown in FIG. 4B ', the covering layer 25 on the original plate 20 is completely removed (etched) in the depth direction from the opening of the resist layer 22 (opening forming step). In this etching, anisotropic etching is desirable to minimize undercut (side etching). As such anisotropic etching, RIE (Reactive Ion Etching) can be preferably employed.

As this etching condition, if the etching selectivity of the coating layer 25 (for example, SiO ₂ ) is set to be larger than that of the original plate 20 (for example, Si), the coating layer 25 is removed so as to penetrate in the thickness direction. However, since the surface of the original plate 20 is hardly removed (etched), it is difficult for the etching depth to vary.

As specific etching conditions, in an ICP type RIE apparatus, an etching gas is supplied at a flow rate of 20 to 300 sccm while the internal pressure is controlled to 0.5 to 10 Pa. As an etching gas, CF ₄ , CHF ₃ , SF ₆ , argon, or the like can be preferably used. Moreover, it is preferable that the power of the upper electrode in the apparatus is set to 100 to 500 W, and the power (bias power) of the lower electrode is set to 30 to 100 W.

  As a result, a covering layer 25 having the same pattern as the remaining resist layer 22 is formed. This covering layer 25 serves as a mask (cover layer) when etching the original plate 20.

  Next, as shown in FIG. 4C, the original plate 20 is removed (etched) from the surface by a predetermined depth from the opening of the resist layer 22 (the same applies to the covering layer 25) (etching step). In this etching, anisotropic etching is desirable to minimize undercut (side etching). As such anisotropic etching, RIE (Reactive Ion Etching) can be preferably employed.

As the etching condition, if the etching selectivity of the covering layer 25 (for example, SiO ₂ ) is set to be smaller than that of the original plate 20 (for example, Si), the original plate 20 is removed (etched) from the surface by a predetermined depth. At this time, even if the resist layer 22 is damaged and does not function as a cover layer, the surface of the coating layer 25 is hardly removed (etched), so that the coating layer 25 functions as a cover layer. Moreover, it is difficult to cause variations in the etching depth.

As specific etching conditions, in an RIE apparatus, an etching gas is supplied at a flow rate of 30 to 70 sccm while the internal pressure of the apparatus is controlled to 0.4 to 0.8 Pa. As the etching gas, CHF ₃ , CF ₄ , HBr or the like is preferably employed. Moreover, it is preferable that the power of the upper electrode in the apparatus is set to 80 to 120 W, and the power (bias power) of the lower electrode is set to 15 to 45 W.

  Next, as shown in FIG. 4D, the resist layer 22 and the covering layer 25 are removed (ashing process) to obtain a master 26, and after the formation of the conductive layer, as shown in FIG. 4E. Then, electrodeposition (electroforming) is performed to laminate a metal plate (master substrate 12) made of Ni metal having a desired thickness (reverse plate forming step). As shown in FIG. 4A. As shown in FIG. 4G, the magnetic layer 14 is formed on the surface of the concavo-convex pattern of the master substrate 12 to obtain the magnetic transfer master disk 10.

  As mentioned above, although embodiment of the manufacturing method of the board | substrate used for manufacture of the master disk for magnetic transfer concerning this invention was described, this invention is not limited to the said embodiment, Various aspects can be taken.

  For example, in the second embodiment, the coating layer 25 is removed so as to penetrate and is used as a mask in the next etching step. However, the coating layer 25 is formed thicker than this, and the coating layer 25 is formed in a predetermined manner. It is also possible to adopt a mode in which only the depth is removed and this is used as a master 26 and a master substrate 12 is obtained by electrodepositing metal on this master 26 to obtain a reversal disc.

  In the present embodiment, the master plate 12 is obtained by electrodepositing metal on the master plate 26 to obtain the reversal plate, but other manufacturing processes can also be adopted. Specifically, a metal plate having a concavo-convex pattern obtained by electrodepositing metal on the master 26 to produce a second master, and re-electrodepositing metal using the second master (reversing disc) And a master substrate can be taken by punching to a predetermined size.

  Furthermore, electrodeposition is performed using the second master to produce a third master, electrodeposition is performed using the third master to produce a metal plate, and a metal plate having an inverted concavo-convex pattern It is possible to adopt a mode in which a master substrate is produced by peeling off the substrate.

  Even if the concave / convex pattern of the master substrate 12 of the master disk 10 is a negative pattern having a concave / convex shape opposite to the positive pattern of FIGS. 3 (G) and 4 (G), the initial magnetic field during magnetic transfer is used. Since the same magnetization pattern can be transferred and recorded by setting the direction of Hi and the direction of the transfer magnetic field Hd to the opposite directions, there is no problem.

Partially enlarged perspective view of a master disk for magnetic transfer manufactured by the substrate manufacturing method according to the present invention Plan view of the master disk for magnetic transfer Sectional drawing which shows each process of the manufacturing method of the board | substrate concerning this invention in order. Sectional drawing which shows each process of the other example of the manufacturing method of the board | substrate which concerns on this invention in order.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Master disk for magnetic transfer, 12 ... Master substrate, 14 ... Magnetic layer, 20 ... Original plate, 22 ... Resist layer, 23 ... Processed layer, 24 ... Electron beam, 25 ... Cover layer, 26 ... Master disc

Claims (5)

In manufacturing method of a large number of fine irregularities shaped master disk for magnetic transfer magnetic layer pattern is formed on the surface,
Ri Oh etching selectivity to the flat surface of the wafer with greater than resist agent, and a work layer forming step of etching selection ratio to form a processed layer of Ah Ru member larger than the wafer,
Applying the resist agent on the surface of the layer to be processed, and forming a layer of the resist agent;
A resist patterning step of forming an opening of the layer of the resist agent on the surface of the layer to be processed by drawing exposure on the layer of the resist agent and subsequent development processing,
An etching step of removing all of the processed layer in the opening direction of the layer of the resist agent in the thickness direction from the surface ;
Removing the resist layer and forming a substrate with a concavo-convex pattern;
A reversing plate forming step of forming a reversing plate made of a metal plate of a predetermined thickness by electrodepositing a metal on the surface of the substrate on which the concavo-convex pattern is formed;
A peeling step of peeling the reversal plate from the substrate and obtaining a master substrate having a reversal pattern of the concavo-convex pattern on the surface;
Forming a magnetic layer on the surface of the concavo-convex pattern of the master substrate;
A method for manufacturing a magnetic transfer master disk. The method of manufacturing a master disk for magnetic transfer according to claim 1, wherein the etching selectivity of the layer to be processed is 2 or more with respect to the resist agent. The method for manufacturing a master disk for magnetic transfer according to claim 1, wherein the work layer is formed by any one of a physical vapor deposition method, a chemical vapor deposition method, and a thermal oxidation method. 4. The method for manufacturing a master disk for magnetic transfer according to claim 1, wherein the layer to be processed is an oxide of Si or a nitride of Si, and the wafer is Si. Method of manufacturing a master disk for magnetic transfer according the any one of claims 1 to 4 is 50 or more etching selectivity of the layer to be processed is to the wafer.

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