JP5175812B2 - Nano mold, mold manufacturing method and magnetic recording medium manufacturing method - Google Patents

Description

  The present invention relates to a nano mold having a nano-order pattern formed thereon, a mold manufacturing method, and a magnetic recording medium manufacturing method.

In recent years, the need for large-capacity image information recording has increased due to the advancement of an advanced information society, and a high recording density of 1 Tb / inch ² is required for magnetic recording media. As such a high-density magnetic recording medium, a patterned magnetic recording medium having a structure in which magnetic dots are separated by a non-magnetic material has attracted attention (see, for example, Non-Patent Document 1).

In the technique described in Non-Patent Document 1, a resist is patterned using nanoimprint, and the magnetic film is etched using the resist as a mask to form separated magnetic dots. However, with such a method, the dot pitch is as large as 100 nm or more, and it is difficult to achieve 1 Tb / inch ² . In addition, since a series of processing operations as described above must be performed for each magnetic recording medium, there is a problem in terms of processing costs.

Therefore, the present inventors have proposed a method of forming a nanohole by performing nanoimprinting using a nano mold on a metal glass substrate and embedding a magnetic material (FePt nanoparticle) in the nanohole ( For example, see Patent Document 1). The nano mold to be used is to form a tungsten thin film mask on the SiO ₂ film formed on the Si substrate by FIB-CVD method using a fluorine-based gas (CHF ₃ or the like). It was formed by etching SiO ₂ by etching.

JP 2008-130210 A

Tsutomu Aoyama, Yumu Sato, Shunji Ishio, “Production Method and Magnetic Properties of Patterned Magnetic Recording Media”, Applied Physics, 2003, Vol. 72, No. 3, p.298-303

However, when SiO ₂ is etched using the Si substrate as an etching stopper, the selectivity between Si and SiO ₂ is not so large, so the etching does not stop at the Si substrate and the etching is performed to the Si substrate, and the etching depth is uneven. Become. Such non-uniformity becomes a problem when manufacturing a nano mold having a smaller diameter and a smaller pitch.

The invention of claim 1 is a method for producing a nano mold used in the nanoimprint method, the first step of forming an etched layer made of an amorphous carbon material on an Al ₂ O ₃ substrate, and a focused ion A second step of forming a thin film pattern on the layer to be etched by beam-assisted chemical vapor deposition; and etching the layer to be etched by dry etching using oxygen gas using the thin film pattern as a mask. And a third step of forming a molded transfer surface on which a pattern is formed.
A nano mold according to a second aspect of the present invention is manufactured by the manufacturing method according to the first aspect.
The invention of claim 3 is a method for producing a nano mold used in the nanoimprint method, wherein a first step of forming an etching target layer made of an amorphous carbon material on a first Al ₂ O ₃ substrate; A second step of forming a thin film pattern on the etching target layer formed on the first Al ₂ O ₃ substrate by focused ion beam assisted chemical vapor deposition, and oxygen gas was used with the thin film pattern as a mask. A third step of etching a layer to be etched by dry etching to form a preliminary mold having a plurality of nano-convex patterns; and a layer to be etched made of an amorphous carbon material on a _second Al ₂ O ₃ substrate a fourth step of forming a fifth step of forming a second resist layer on the etched layer which is formed on the Al ₂ O ₃ substrate of the imprint formed by the preliminary mold against the resist layer The sixth step of forming the mask pattern with the resist layer by shifting the preliminary mold a plurality of times so that the molding transfer position of the nano-convex pattern does not overlap, and the dry process using oxygen gas with the resist pattern as a mask And a seventh step of etching a layer to be etched of the second Al ₂ O ₃ substrate by etching to form a molded transfer surface having a plurality of nano-concave patterns.
The invention of claim 4 is a method of manufacturing a nano mold used in the nanoimprint method, and includes a first step of forming an etched layer made of an amorphous carbon material on a first Al ₂ O ₃ substrate. A second step of forming a thin film pattern on the etching target layer formed on the first Al ₂ O ₃ substrate by focused ion beam assisted chemical vapor deposition, and oxygen gas was used with the thin film pattern as a mask. A third step of etching a layer to be etched by dry etching to form a preliminary mold having a plurality of nano-convex patterns; and a layer to be etched made of an amorphous carbon material on a _second Al ₂ O ₃ substrate a fourth step of forming a fifth step of forming a resist layer on the etched layer which is formed on the second Al ₂ O ₃ substrate, imprinting by the preliminary mold against the resist layer A sixth step of performing molding a plurality of times by shifting the preliminary mold so that the molding transfer positions of the nano-convex patterns do not overlap, and forming a mask pattern by a resist layer to expose a part of the surface of the layer to be etched; A seventh step of forming a sputtered thin film on the surface of the exposed layer to be etched, and etching the layer to be etched of the second Al ₂ O ₃ substrate by dry etching using oxygen gas using the sputtered thin film as a mask, And an eighth step of forming a molded transfer surface having a plurality of nano-convex patterns.
According to a fifth aspect of the present invention, in the method for producing a nano mold according to the third or fourth aspect, in the sixth step, the pattern pitch N or the like is formed in the pattern pitch direction of the nano-convex pattern formed in the preliminary mold. The imprint molding using a preliminary mold is performed N times while shifting by minutes.
According to a sixth aspect of the present invention, in the method for manufacturing a nano mold according to the fifth aspect, the pattern pitch is divided into N equal parts with respect to each of two orthogonal pattern pitch directions of the nano-convex pattern formed on the preliminary mold. The imprint molding using the preliminary mold is performed N times while shifting each time.
The nano metal mold | die which concerns on invention of Claim 7 was manufactured with the manufacturing method as described in any one of Claims 3-6, It is characterized by the above-mentioned.
The method for producing a nano mold according to the invention of claim 8 is to press the metal glass substrate against the molding transfer surface of the nano mold according to claim 7 while holding the metallic glass substrate in the supercooled liquid temperature range. It is characterized by forming a formed mold.
According to a ninth aspect of the present invention, there is provided a magnetic recording medium manufacturing method comprising: a first step of forming a soft magnetic layer on a substrate; and a metal glass substrate is placed on the soft magnetic layer, and the metal glass substrate is A second step of forming a metal glass layer having a desired thickness on the soft magnetic layer by pressurizing while maintaining the supercooled liquid temperature range, and maintaining the metal glass layer in the supercooled liquid temperature range A third step of pressing the molding transfer surface of the nano mold according to claim 7 to form a plurality of recesses or projections, and a fourth step of forming a magnetic body in each of the plurality of recesses or projections And a process.

  According to the present invention, a nanopattern having a smaller diameter and a smaller pitch can be formed.

It is a figure which shows a magnetic recording medium, (a) is a top view, (b) is AA sectional drawing. It is a figure explaining the manufacturing method of a magnetic recording medium, (a) is a figure which shows a 1st process and (b) is a 2nd process. It is a figure explaining the manufacturing method of a magnetic recording medium, (a) is a 3rd process, (b) is a figure which shows a 4th process. It is a figure explaining stoppers 202 and 15. It is a figure explaining the manufacturing method of the metal mold | die 2, (a) shows a 1st process, (b) shows a 2nd process, (c) shows the mask pattern 22 formed on the DLC film 21. . It is a figure explaining the manufacturing method of the metal mold | die 2, (a) shows a 3rd process, (b) shows the shaping | molding transcription | transfer surface of the metal mold | die 2. FIG. It is a figure explaining the 2nd example of a metal mold manufacturing method, and shows from the 1st process to the 4th process. It is a figure explaining the 2nd example of a metal mold manufacturing method, and shows from the 5th process to the 8th process. 7A is a plan view of a resist 72, FIG. 7A shows a state after the step of FIG. 7B, FIG. 7B shows a state after the step of FIG. 7C, and FIG. Indicates a pattern. (A) is a perspective view of the mold 7, and (b) is a perspective view of the final mold 8. FIG. 6 shows another example of a magnetic recording medium, where (a) is a plan view and (b) is a cross-sectional view along BB. It is a figure which shows the manufacturing process of the metal mold | die 9. FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. 1A and 1B are diagrams showing a magnetic recording medium 1, in which FIG. 1A is a plan view and FIG. 1B is a cross-sectional view taken along line AA. On the substrate 11 of the magnetic recording medium 1, an amorphous soft magnetic layer 12 and a metallic glass layer 13 are formed in this order. A plurality of recesses 130 are regularly formed in the metal glass layer 13, and the magnetic bodies 14 constituting the magnetic recording layer (hard magnetic layer) are embedded in each recess 130.

  In the magnetic recording medium shown in FIG. 1, the nonmagnetic metallic glass layer 13 is interposed between the magnetic bodies 14, so that each magnetic body 14 constitutes a magnetically independent recording bit. The substrate 11 is made of a nonmagnetic material such as aluminum, oxide glass, or metal glass. The soft magnetic layer 12 has a function of supporting a recording magnetic field from the magnetic head, and the recording magnetic field of the magnetic head forms a closed loop through the soft magnetic layer 12 to improve recording magnetic field capture and signal reproduction sensitivity. Is planned. The soft magnetic layer 12 is made of a soft magnetic material containing Fe, Ni, Co, Pd, or the like, and a metallic glass exhibiting soft magnetism can also be used. As will be described later, since the entire substrate is heated to the molding temperature Tm in the manufacturing process, when the soft magnetic layer 12 is an amorphous material, the crystallization temperature of the soft magnetic material is higher than the molding temperature Tm. Use things.

The total thickness t1 of the metallic glass layer 13 is about 20 nm, and the thickness t2 of the bottom portion 131 of the recess 130 is about several nm or less. This portion corresponds to the intermediate layer of a conventional perpendicular magnetic recording medium. Further, when the pitch P of the recesses 130 formed in a matrix is set to about 25 nm or less, a recording density of 1 Tb / inch ² or more can be achieved. As described later, the metallic glass material used for the metallic glass layer 13 is a Pt-based (platinum) amorphous alloy, a Zr-based (zirconium-based) amorphous alloy, a La-based (lanthanum-based) amorphous alloy, or a Pd-based (palladium-based). There are amorphous alloys. For the magnetic body 14, nanomagnetic particles such as FePt nanoparticles, a Co / Pd multilayer film, or the like is used.

<< Description of Manufacturing Method of Magnetic Recording Medium 1 >>
Next, a method for manufacturing the magnetic recording medium 1 will be described with reference to FIGS. In the present embodiment, the fine uneven pattern of the metal glass layer 13 is formed by a nanoimprint method. First, as shown in FIG. 2A, a soft magnetic layer 12 having a predetermined thickness is formed on a substrate 11 by sputtering deposition or the like. In the step shown in FIG. 2B, the metallic glass layer 13 is formed by sputtering deposition or the like.

  Here, the metal glass layer 13 is formed by sputter deposition, but it may be formed by the following thin film lamination process. That is, a thin metal glass substrate is disposed on the soft magnetic layer 12, and the metal glass substrate is heated to a supercooled liquid temperature range described later and pressed with a press to form a metal glass layer 13 having a desired thickness. And The metallic glass layer 13 is fixed to the soft magnetic layer 12 in the pressure molding process.

  Next, as shown in FIGS. 3A and 3B, irregularities are formed on the metallic glass layer 13 by the nanoimprint method using the mold 2. In the mold 2, a convex portion 200 corresponding to the concave portion 130 to be formed in the metallic glass layer 13 and a concave portion 201 corresponding to the convex portion 132 are formed. A method for creating the mold 2 will be described later.

  An amorphous alloy called metallic glass has a glass transition temperature Tg on the lower temperature side than the crystallization temperature Tx, and a stable supercooled liquid temperature range ΔTx (= Tx−Tg). In this supercooled liquid temperature range, the metallic glass exhibits a complete Newtonian viscous flow, and has an excellent fine forming property (fine shape transferability) since it can be processed by viscous flow with low stress. In the present embodiment, by utilizing such a property of the metal glass, the fine uneven shape on the order of nanometers formed on the mold 2 is transferred to the metal glass layer 13, thereby making the fine uneven shape easy and high. It is made to form with accuracy.

  Examples of such amorphous alloys include Pt-based (platinum) amorphous alloys, Zr-based (zirconium-based) amorphous alloys, La-based (lanthanum-based) amorphous alloys, and Pd-based (palladium-based) amorphous alloys. For example, a Pt-based Pt48.75Pd9.75Cu19.5P22 alloy has a glass transition temperature Tg = 502.3K, a crystallization temperature Tx = 587.7K, and a supercooled liquid temperature range ΔTx = 85.4K. The Pd-based Pd40Cu30Ni10P20 alloy has a glass transition temperature Tg = 577K, a crystallization temperature Tx = 673K, and a supercooled liquid temperature range ΔTx = 96K, and any alloy can be formed in a relatively low temperature range. .

  In the step shown in FIG. 3A, the substrate 11 on which the metal glass layer 13 is formed and the mold 2 are heated to a molding temperature Tm higher than the glass transition temperature Tg13 of the metal glass layer 13, and a predetermined load is applied. In addition, the metallic glass layer 13 is imprinted. Thereafter, the substrate 11 and the mold 2 are cooled, and when their temperature becomes lower than the glass transition temperature Tg13 of the metallic glass layer 13, the load is removed. As a result, as shown in FIG. 3 (b), a recess 130 having a depth (t 1 -t 2) is formed in the metallic glass layer 13. For example, the molding conditions when a Pd40Cu30Ni10P20 alloy is used are Tm = 540K, an average load stress of 20 MPa, and a molding time of 250 sec.

  In addition, by forming the stoppers 202 and 15 as shown in FIG. 4 on the mold 2 and the soft magnetic layer 2, the bottom thickness t2 of the recess 130 can be accurately managed. The stopper 202 of the mold 2 is formed at the same height as the convex portion 200, and the stopper 15 having a thickness t2 is formed by sputtering deposition or the like. A material having a melting point higher than the molding temperature Tm may be used for the stopper 15.

  Then, the magnetic recording medium 1 as shown in FIG. 1 is obtained by embedding the magnetic body 14 in the recess 130 formed as shown in FIG. For the magnetic body 14, for example, FePt nanoparticles are used. FePt nanoparticles are formed by various chemical solution methods.

  The magnetic material 14 enters the recess 130 by uniformly spreading the magnetic material 14 of FePt nanoparticles on the metal glass layer 13 and removing the excess magnetic material 14 with a squeegee blade or the like. Therefore, if the size of the recess 130 is approximately the same as the size of the FePt nanoparticle, one FePt nanoparticle is embedded in each recess 130. Of course, you may set the recessed part 130 to the dimension in which several FePt nanoparticles are embedded. Note that a protective film such as a DLC (diamond-like carbon) film may be formed after the magnetic material 14 is embedded in order to protect the recording surface.

<< Die manufacturing method 1 >>
5 and 6 are views for explaining a first example of the method for manufacturing the mold 2. In the first step shown in FIG. 5A, the DLC film 21 is formed on the surface of the Al ₂ O ₃ substrate 20. Although the DLC film 21 is used here, the film 21 is not limited to DLC, and an amorphous carbon material such as glassy carbon can be used. Since the DLC film 21 is formed by, for example, the ECR plasma CVD method or the like, it is easy to reduce the film thickness to several tens of nm or less, and has characteristics such as high hardness and wear resistance. The film thickness of the DLC film 21 is set according to the height of the convex pattern (dot pattern) formed on the mold 2. For example, it is set to 20 nm.

In the second step of FIG. 5B, a thin film of platinum (Pt) is formed by focused ion beam assisted chemical vapor deposition (FIB-CVD), and a mask pattern 22 is formed on the DLC film 21. If the DLC film 21 is doped with boron, FIB-CVD is facilitated. In this patterning, a Ga ⁺ beam is irradiated while Pt (Et) (CO) ₂ is sprayed as a deposition gas on the processing region. As a result, Pt as a gas decomposition substance is deposited on the surface of the DLC film 21, and a Pt thin film is formed. FIG. 5C shows a plurality of mask patterns 22 formed on the DLC film 21. Although the cross-sectional shape of the dot pattern is determined by the shape of the mask pattern 22, the shape is not limited to the rectangle as shown in FIG.

  In the third step shown in FIG. 6A, the DLC film 21 is etched by dry etching using oxygen gas using the mask pattern 22 of the Pt thin film. A plurality of convex portions 200 corresponding to the concave portions 130 of the metal glass layer 13 are formed on the molding transfer surface of the mold 2 formed in this way, as shown in FIG. Usually, the ratio of the diameter and height of the convex portion 200 is set to about 1: 2. For example, in the case of a convex pattern having a diameter of about 10 nm, the height is about 20 nm.

In the technique described in Patent Document 2 described above, a Si substrate is used as a substrate, and a SiO ₂ film is formed on the Si substrate. Then, the SiO ₂ film is etched (RIE) to form a convex pattern. A fluorine-based gas (CHF ₃ or the like) is used during etching. In the case of dry etching using a fluorine-based gas containing hydrogen such as CHF _3, oxygen generated during etching oxidizes chemical species (CF and CF ₂ ) that form a nonvolatile material (polymerized film) on SiO _2. Removed.

However, since there is no oxygen on Si, a polymer film (COF or COF ₃ ) is formed, and accelerated ions are consumed to remove the polymer film. This is a mechanism for improving the selectivity between Si and SiO ₂ . However, under the SiO ₂ etching conditions for forming a nanopattern as in the present embodiment, the high-frequency output is high and the physical workability by sputtering is high, so the selection ratio between Si and SiO ₂ is low. For this reason, the etching is not stopped by Si but the Si substrate is etched, and the etching depth is likely to vary, which hinders the miniaturization of the diameter and pitch of the convex pattern.

Therefore, in this embodiment, an Al ₂ O ₃ substrate 20 is used instead of the Si substrate, an amorphous carbon film (DLC film 21) is formed as an etching target layer, and dry etching using oxygen gas is performed. Thus, the amorphous carbon film was etched. In this case, since the Al ₂ O ₃ substrate 20 is difficult to be etched, the etching stops at the Al ₂ O ₃ substrate 20, and a convex pattern having a uniform height can be formed in a wide area. As a result, a fine pattern having a diameter of 12 nm and a pitch of 25 nm can be formed.

<< Die manufacturing method 2 >>
7-9 is a figure explaining the 2nd example of the manufacturing method of a metal mold | die. In the second example, a mold having a convex pattern with a smaller pitch is formed using the mold 2 described above. First, as shown in FIG. 7A, a DLC film 71 is formed on the Al ₂ O ₃ substrate 70. This step is the same as that shown in FIG. Further, a resist 72 is formed on the DLC film 71.

  Next, as shown in FIG. 7B, the mold 2 formed by the manufacturing method 1 is pressed to perform nanoimprint molding. Since the convex portions 200 are formed at the pitch P in the mold 2, holes 721 a corresponding to the convex portions 200 are formed at the pitch P in the resist 72. FIG. 9 is a plan view of the resist 72, and FIG. 9 (a) shows a state after the step of FIG. 7 (b).

In FIG. 7C, the mold 2 or the Al ₂ O ₃ substrate 70 is shifted by P / 2, and the mold 2 is pressed again to perform nanoimprint molding. As a result, holes 721b corresponding to the convex portions 200 are formed in the resist 72, respectively. FIG. 7 (d) shows a cross-sectional view of the substrate after the step of FIG. 7 (c), and FIG. 9 (b) shows a plan view of the resist after the step of FIG. 7 (c). is there. In FIG. 9A, a hole 721a denoted by reference numeral 1 is a hole formed in the process of FIG. 7B. In FIG. 7B, imprint molding is performed with respect to the Al ₂ O ₃ substrate 70 on which the resist 72 is formed by relatively shifting the mold 2 by a pitch P / 2 in the x direction. Therefore, the hole 721b is formed so as to be shifted by P / 2 in the x direction with respect to the hole 721a.

  Thereafter, by performing imprint molding shifted by P / 2 pitch in the y direction and imprint molding shifted by P / 2 pitch in the x direction and y direction, respectively, the P / 2 pitch as shown in FIG. A resist pattern in which holes are arranged is formed. A hole 721c denoted by reference numeral 3 indicates a hole formed by imprint molding shifted by P / 2 pitch in the y direction, and a hole 721d denoted by reference numeral 4 is shifted by P / 2 pitch in the x direction and y direction, respectively. 2 shows holes formed by imprint molding.

As a method of step-driving the Al ₂ O ₃ substrate 70 on which the resist 72 is formed with respect to the mold, for example, the Al ₂ O ₃ substrate 70 is moved in the x direction and the y direction by a driving device using a piezoelectric element. There is a step driving method.

  Next, as shown in FIG. 8A, the DLC film 71 is etched using the resist 72 in which the holes 721a to 721d are formed as a mask. As a result, holes 710 corresponding to the holes 721a to 721d are formed in the DLC film 71, respectively. Thereafter, when the resist 72 is removed, the mold 7 as shown in FIG. 8B is formed. FIG. 10 is a perspective view of the mold 7, and a large number of holes (nanoholes) 710 are formed in the mold 7 at a pitch P / 2.

  In the second manufacturing method, as shown in FIGS. 8C and 8D, the metal glass substrate 80 is subjected to thermal imprint processing using the mold 7 to obtain the final used for manufacturing the magnetic recording medium. A typical mold 8 is formed. Since the process of heat imprinting the metal glass substrate 80 is performed in the same manner as described with reference to FIG. 2, the description thereof is omitted here. By this thermal imprint process, the metal glass enters the hole 710 of the mold 7, and the convex portion 81 corresponding to the hole 710 is formed on the metal glass substrate 80 side. FIG. 10B is a perspective view of the mold 8 formed as described above. The dot pitch of the mold 8 (the pitch of the protrusions 81) is half of the dot pitch P in the mold 2, and a mold having a finer nanopattern can be easily formed.

  In the example described above, the mold 2 is shifted by P / 2 pitch and imprint molding is performed four times to form the mold 7 (nanohole pattern) having the pitch P / 2, and the pitch P / 2 is formed from the mold 7. The mold 8 (nanodot pattern) was formed. Similarly, a nano mold having a pitch P / N can be formed by repeatedly performing imprint molding while shifting the molding transfer position of the convex pattern. Here, N is an integer of 3 or more, and the number of imprint moldings is N × N. Further, as shown in FIG. 9B, a mold having a different pattern pitch between the x direction and the y direction may be used. In this case, the number of imprint moldings is N.

  In the example shown in FIGS. 8A and 8B, etching is performed using the patterned resist 72 as a mask. However, using a mask formed by a method described below, The DLC film 71 may be etched.

FIG. 12A is the same as the cross-sectional view shown in FIG. Although not shown in FIG. 7D, actually, the resist 72 remains slightly thin on the surface of the DLC film 71 in the hole 721a as shown in FIG. In the step shown in FIG. 12A, the thin resist on the DLC film 71 is removed by, for example, ashing using N ₂ plasma, and the surface of the DLC film 71 is exposed.

  In the step shown in FIG. 12B, a sputtered film 73 such as Pt (hereinafter referred to as a Pt film 73) is formed on the resist 72 and the exposed DLC film 71 surface. Thereafter, the resist 72 is removed to form a mask pattern on the DLC film 71 by the Pt film 73 as shown in FIG. In this mask pattern, rectangular island-shaped Pt films 73 are formed in the same arrangement as the convex portions 81 in FIG.

  Next, when the DLC film 71 is etched using the Pt film 73 as a mask, only the portion of the DLC film 71 where the Pt film 73 is formed remains, and a mold 9 (convex pattern) as shown in FIG. The The mold 9 has the same shape as the mold 8 shown in FIG. 10B, and the convex portions 91 made of the Pt film 73 and the DLC film 71 are arranged in the same manner as the convex portions 81 in FIG. 10B. Has been. In the case of the mold 9, since a sputtered film such as a Pt film is used as a mask, the etching rate is greatly different from that of the DLC film 71 that is an etching target layer, that is, the etching selectivity is high, and the resist 72 is formed. A finer pattern than that used for a mask can be processed. As in the case where the mold 8 is formed, the surface of the mold 9 on which the convex portion 91 is formed is transferred to the metal glass substrate, thereby forming the metal glass mold on which the nanoconcave pattern is formed. You may do it.

  In the magnetic recording medium 1 shown in FIG. 1, a plurality of recesses 130 are formed in the metal glass layer 13 and the magnetic body 14 is embedded therein. However, as shown in FIG. A plurality of portions 133 may be formed, and the magnetic body 14 may be formed on the convex portion 133. In FIG. 11, (a) is a plan view and (b) is a BB cross-sectional view. In this case, the convex part 133 is formed in the metallic glass layer 13 by the thermal imprint process using the metal mold | die 7 shown to Fig.10 (a).

  Each of the embodiments described above may be used alone or in combination. This is because the effects of the respective embodiments can be achieved independently or synergistically. In addition, the present invention is not limited to the above embodiment as long as the characteristics of the present invention are not impaired. For example, in the above-described embodiment, the nano mold for forming the magnetic recording medium has been described as an example. However, the method of manufacturing the nano mold according to the present invention can be applied to an optical element such as a DVD or a micro lens array, or a microchemical It can also be applied to a mold for forming a chip or the like.

1: magnetic recording medium, 2, 7, 8: mold, 11: substrate, 12: soft magnetic layer, 13: metallic glass layer, 14: magnetic material, 15, 202: stopper, 20, 70: Al ₂ O ₃ Substrate, 21, 71: DLC film, 22: Mask pattern, 72: Resist, 80: Metal glass substrate, 130, 201: Recess, 81, 132, 133, 200: Protrusion, 710, 721a to 712d: Hole

Claims (9)

A method for producing a nano mold used in the nanoimprint method,
A first step of forming an etched layer made of an amorphous carbon material on an Al ₂ O ₃ substrate;
A second step of forming a thin film pattern on the etched layer by focused ion beam assisted chemical vapor deposition;
Using the thin film pattern as a mask, and etching the layer to be etched by dry etching using oxygen gas to form a molded transfer surface on which a plurality of nano-convex patterns are formed. A method for manufacturing a nano mold.   A nano mold manufactured by the manufacturing method according to claim 1. A method for producing a nano mold used in the nanoimprint method,
A first step of forming an etched layer made of an amorphous carbon material on a first Al ₂ O ₃ substrate;
A second step of forming a thin film pattern on the etching target layer formed on the first Al ₂ O ₃ substrate by focused ion beam assisted chemical vapor deposition;
A third step of forming a preliminary mold having a plurality of nano-convex patterns by etching the layer to be etched by dry etching using oxygen gas using the thin film pattern as a mask;
A fourth step of forming an etched layer made of an amorphous carbon material on the second Al ₂ O ₃ substrate;
A fifth step of forming a resist layer on the layer to be etched formed on the second Al ₂ O ₃ substrate;
Imprint molding with the preliminary mold on the resist layer is performed a plurality of times while shifting the preliminary mold so that molding transfer positions of the nano-convex patterns do not overlap, and a mask pattern with the resist layer is formed. Process,
A seventh step of etching a layer to be etched of the second Al ₂ O ₃ substrate by dry etching using oxygen gas using the resist pattern as a mask to form a molded transfer surface having a plurality of nanoconcave patterns; A method for producing a nano mold, comprising: A method for producing a nano mold used in the nanoimprint method,
A first step of forming an etched layer made of an amorphous carbon material on a first Al ₂ O ₃ substrate;
A second step of forming a thin film pattern on the etching target layer formed on the first Al ₂ O ₃ substrate by focused ion beam assisted chemical vapor deposition;
A third step of forming a preliminary mold having a plurality of nano-convex patterns by etching the layer to be etched by dry etching using oxygen gas using the thin film pattern as a mask;
A fourth step of forming an etched layer made of an amorphous carbon material on the second Al ₂ O ₃ substrate;
A fifth step of forming a resist layer on the layer to be etched formed on the second Al ₂ O ₃ substrate;
Imprint molding with the preliminary mold on the resist layer is performed a plurality of times by shifting the preliminary mold so that the molding transfer positions of the nano-convex patterns do not overlap, and a mask pattern with the resist layer is formed to form the mask. A sixth step of exposing a part of the surface of the etching layer;
A seventh step of forming a sputtered thin film on the surface of the exposed layer to be etched;
An eighth step of forming a molding transfer surface having a plurality of nano-convex patterns by etching the etching target layer of the second Al ₂ O ₃ substrate by dry etching using oxygen gas using the sputtered thin film as a mask; A method for producing a nano mold, comprising: In the manufacturing method of the nano metal mold according to claim 3 or 4,
In the sixth step, imprint molding with the preliminary mold is performed N times while shifting the pattern pitch by N equal parts in the pattern pitch direction of the nano-convex pattern formed on the preliminary mold. Manufacturing method of nano mold. In the manufacturing method of the nano metal mold according to claim 5,
The imprint molding by the preliminary mold is performed N times while shifting the pattern pitch by N equal parts for each of the two orthogonal pattern pitch directions of the nano-convex pattern formed on the preliminary mold. Manufacturing method of nano mold.   The nano metal mold | die manufactured with the manufacturing method as described in any one of Claims 3-6.   The metal glass substrate is pressed against the molding transfer surface of the nano mold according to claim 7 while maintaining the supercooled liquid temperature range to form a nano pattern-formed mold. Mold manufacturing method. A first step of forming a soft magnetic layer on the substrate;
A metal glass substrate is placed on the soft magnetic layer, and the metal glass substrate is pressed while being held in the supercooled liquid temperature range, thereby forming a metal glass layer having a desired thickness on the soft magnetic layer. A second step of forming;
A third step of forming a plurality of concave portions or convex portions by pressing the molding transfer surface of the nano mold according to claim 7 while maintaining the metallic glass layer in the supercooled liquid temperature range;
And a fourth step of forming a magnetic material in each of the plurality of concave portions or convex portions.

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