Imprint mold

Abstract

To provide an imprint mold capable of suppressing breakage of a pattern part of the mold and a transfer pattern while securing dimensional accuracy of the transfer pattern transferred to a workpiece.SOLUTION: The imprint mold 10 includes a first concave-convex pattern part 10P. In the first uneven pattern part 10P, a composite modulus of elasticity measured by a microindentation test is 90GPa or more and 195GPa or less. In addition, in the first uneven pattern portion 10P, the hardness measured by the microindentation test is 8GPa or more and 12GPa or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an imprint mold. [Background technology]

[0002] Imprinting is known as a technique for forming fine circuit patterns for semiconductor devices and fine patterns for imparting optical functions. The imprinting method uses a metal mold on which a reverse pattern of the fine pattern to be transferred is formed. The imprinting method transfers the pattern by pressing the mold into an imprint resin (the workpiece) and then curing the imprint resin with heat or light (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-194142 Summary of the Invention [Problem to be solved by the invention]

[0004] In the imprinting method, if the pattern portion of the mold is too soft, the mold itself undergoes a large amount of deformation when the pattern is transferred to the imprint resin, resulting in low dimensional accuracy of the transfer pattern transferred to the imprint resin. On the other hand, if the pattern portion of the mold is too hard, the pattern portion becomes relatively brittle, which may make the pattern portion of the mold more susceptible to breakage depending on the pattern shape of the mold. Furthermore, if the rigidity of the pattern portion of the mold is too high, the adhesion between the pattern portion of the mold and the imprint resin becomes too strong, which may result in poor releasability. In this case, the transfer pattern may be more susceptible to breakage during mold release depending on the shape of the transfer pattern transferred to the imprint resin. [Means for solving the problem]

[0005] The imprint mold for solving the above problems is an imprint mold having a concave-convex pattern portion, in which the concave-convex pattern portion has a composite elastic modulus of 90 GPa or more and 195 GPa or less as measured by a microindentation test.

[0006] The imprint mold for solving the above problems is an imprint mold having a concave-convex pattern portion, in which the hardness of the concave-convex pattern portion measured by a microindentation test is 8 GPa or more and 12 GPa or less.

[0007] According to each of the above configurations, by setting the composite elastic modulus measured by a microindentation test to 195 GPa or less in the concave-convex pattern portion or the hardness measured by a microindentation test to 12 GPa or less in the concave-convex pattern portion, damage to the concave-convex pattern portion and damage to the transfer pattern formed on the workpiece can be suppressed. Also, by setting the composite elastic modulus measured by a microindentation test to 90 GPa or more in the concave-convex pattern portion or the hardness measured by a microindentation test to 8 GPa or more in the concave-convex pattern portion, dimensional accuracy of the transfer pattern transferred to the workpiece can be ensured.

[0008] In the imprint mold, the material of the concave-convex pattern may include at least one selected from the group consisting of Si and metal, and oxides, nitrides, and oxynitrides of Si or metal. According to this configuration, the concave-convex pattern can be processed so that the composite elastic modulus of the concave-convex pattern, measured by a microindentation test, is 90 GPa or more and 195 GPa or less. Similarly, by forming the concave-convex pattern from the above material, the concave-convex pattern can be processed so that the hardness of the convex pattern, measured by a microindentation test, is 8 GPa or more and 12 GPa or less.

[0009] In the above imprint mold, the concave-convex pattern portion may have a line pattern including a plurality of convex streaks extending in an extension direction and aligned along an arrangement direction intersecting the extension direction, and each convex streak has a first line width of 1000 nm or less in a cross-sectional view perpendicular to the extension direction, and the ratio of the height of the convex streak to the first line width may be no more than 2. Also, in the above imprint mold, the concave-convex pattern portion may have a dot pattern including a plurality of convex portions aligned along each of a first direction and a second direction intersecting the first direction, and each convex portion has a second line width of 1000 nm or less in a cross-sectional view perpendicular to the second direction, and the ratio of the height of the convex portion to the second line width may be no more than 2. According to each of the above configurations, damage to the convex streaks and convex portions of the concave-convex pattern portion can be suppressed while ensuring dimensional accuracy of the transfer pattern transferred to the workpiece.

[0010] In the above imprint mold, the concave-convex pattern portion may have a space pattern including a plurality of recesses extending in an extension direction, the plurality of recesses being aligned along an arrangement direction intersecting the extension direction, and each recess has a third line width of 1000 nm or less in a cross-sectional view perpendicular to the extension direction, and the ratio of the depth of the recess to the third line width may be no more than 2. In the above imprint mold, the concave-convex pattern portion may have a hole pattern including a plurality of recesses aligned along each of a first direction and a second direction intersecting the first direction, and each recess has a fourth line width of 1000 nm or less in a cross-sectional view perpendicular to the second direction, and the ratio of the depth of the recess to the fourth line width may be no more than 2. According to each of the above configurations, it is possible to ensure dimensional accuracy of the transfer pattern transferred to the workpiece while suppressing damage to the transfer pattern formed on the workpiece.

[0011] In the imprint mold, the concave-convex pattern portion may have a release layer on its surface. According to the above configuration, by providing the release layer, it is possible to suppress release defects of the imprint resin as the workpiece. [Effects of the Invention]

[0012] According to the present disclosure, damage to the pattern portion of the mold and the transfer pattern can be suppressed while ensuring the dimensional accuracy of the transfer pattern transferred to the workpiece. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a cross-sectional view of the imprint mold of the first embodiment. [Figure 2] FIG. 2 is a cross-sectional view of the imprint mold of the second embodiment. [Figure 3] FIG. 3 is a cross-sectional view of an imprint mold according to a third embodiment. [Figure 4] FIG. 4 is a cross-sectional view of an imprint mold according to the fourth embodiment. [Figure 5] FIG. 5 is a table showing the manufacturing conditions and evaluation results of samples a1 to a21 in the test examples. [Figure 6] FIG. 6 is a table showing the manufacturing conditions and evaluation results of samples b1 to b21 in the test examples. [Figure 7] FIG. 7 is a table showing the manufacturing conditions and evaluation results of samples c1 to c21 in the test examples. [Figure 8] FIG. 8 is a table showing the manufacturing conditions and evaluation results of samples d1 to d21 in the test examples. DETAILED DESCRIPTION OF THE INVENTION

[0014] First to fourth embodiments of the imprint mold will be described below with reference to Figures 1 to 4. The imprint molds of the respective embodiments have pattern portions with different pattern shapes. The imprint molds of the respective embodiments are used in an imprint method to transfer the pattern shape of the imprint mold to an imprint resin.

[0015] (Imprint mold 10 of the first embodiment) An imprint mold 10 of a first embodiment will be described with reference to FIG. 1, the imprint mold 10 of the first embodiment has a first concave-convex pattern portion 10P. The first concave-convex pattern portion 10P has a line pattern. A space pattern that is the inverse of the line pattern of the first concave-convex pattern portion 10P is transferred to a workpiece by imprinting using the imprint mold 10.

[0016] The first concave-convex pattern portion 10P includes unit shapes U1 repeatedly arranged along a first direction D1 at a predetermined pitch P1. The pitch P1 is, for example, 500 nm or more and 10,000 nm or less. Each unit shape U1 includes a ridge 11 extending in a second direction D2 intersecting the first direction D1 and a bottom surface 12. That is, the first direction D1 corresponds to the arrangement direction in which the multiple ridges 11 are arranged. The second direction D2 corresponds to the extension direction in which the ridges 11 extend.

[0017] The second direction D2 is, for example, a direction perpendicular to the first direction D1. The first direction D1 and the second direction D2 are parallel to the plane in which the first uneven pattern portion 10P extends. The height direction is defined as a third direction D3.

[0018] The ridges 11 have a rectangular cross-sectional shape in a cross section perpendicular to the second direction D2. The bottom surfaces 12 are located between the ridges 11 of adjacent unit shapes U1. The bottom surfaces 12 are located at the bottom of the first uneven pattern portion 10P.

[0019] The ridges 11 have a first line width W1 along the first direction D1. For example, the first line width W1 is 100 nm or more and 1000 nm or less in a cross-sectional view perpendicular to the second direction D2. The first line width W1 may be, for example, the width of the base end of the ridges 11, the width of the tip end of the ridges 11, or the width of a midpoint between the base end and the tip end in a cross-sectional view perpendicular to the second direction D2. Furthermore, the first line width W1 may be, for example, the average value of the widths of the base end and the tip end in a cross-sectional view perpendicular to the second direction D2, or the average value of the width in the section from the base end to the tip end.

[0020] The first line width W1 of the ridges 11 is equal to or smaller (W1≦P1−W1) than the width (P1−W1) along the first direction D1 at the bottom surface 12. The first line width W1 of the ridges 11 is also sufficiently smaller than the length of the ridges 11 extending in the second direction D2.

[0021] The ridges 11 have a first height H1 along the third direction D3. The first height H1 corresponds to the distance from the base end to the tip end of the ridges 11 in a cross-sectional view perpendicular to the second direction D2. For example, the first height H1 is 100 nm or more and 1000 nm or less in a cross-sectional view perpendicular to the second direction D2.

[0022] The protrusions 11 have a predetermined first aspect ratio in a cross-sectional view perpendicular to the second direction D2. The first aspect ratio is the ratio (H1 / W1) of a first height H1 to a first line width W1. The first aspect ratio is, for example, 0.5 or more and 2 or less. That is, the first line width W1 and the first height H1 of the protrusions 11 are set so that the first aspect ratio falls within the range of 0.5 or more and 2 or less.

[0023] The first concave-convex pattern portion 10P includes a portion having a composite modulus of elasticity measured by a microindentation test of 90 GPa or more and 195 GPa or less. The first concave-convex pattern portion 10P also includes a portion having a hardness measured by a microindentation test of 8 GPa or more and 12 GPa or less. The measured composite modulus is a physical property value that represents the hardness of the elastic deformation components of the material. The composite modulus reflects the elastic deformation of the material being tested and the elastic deformation of the indenter. The measured hardness is a physical property value that represents the hardness including both the elastic deformation and plastic deformation components of the material. The microindentation test for measuring the composite modulus and hardness will be described later.

[0024] The material of the first concave-convex pattern portion 10P includes at least one selected from the group consisting of Si, metal, and oxide, nitride, and oxynitride of Si or metal. The material of the first concave-convex pattern portion 10P is selected from materials that can satisfy the above-mentioned numerical ranges for the composite elastic modulus and hardness in a microindentation test after being processed to form the pattern shape of the first concave-convex pattern portion 10P.

[0025] (Method for manufacturing imprint mold 10) An example of a method for manufacturing the imprint mold 10 when the imprint mold 10 is a master mold will be described below.

[0026] In one example of a method for manufacturing the imprint mold 10 according to this embodiment, first, a laminate is prepared by laminating a first layer containing a material constituting the first concave-convex pattern portion 10P and a second layer composed of a resist material. The resist material may be, for example, an electron beam resist material or an ultraviolet resist material. The resist material of the second layer is then exposed to electron beams or ultraviolet light and developed. This forms a pattern shape in the resist material of the second layer. Thereafter, the laminate with the pattern shape formed in the resist material of the second layer is dry-etched to form a pattern shape in the first layer containing the material constituting the first concave-convex pattern portion 10P. The resist material of the second layer is then removed to produce the imprint mold 10 in which the first concave-convex pattern portion 10P is formed in the first layer.

[0027] The composite elastic modulus and hardness measured by a microindentation test for the imprint mold 10 are affected by factors such as thermal load, ion penetration, and surface damage during the manufacturing process. In other words, the composite elastic modulus and hardness measured by a microindentation test can be controlled by changing the processing conditions for forming the first concave-convex pattern portion 10P during the manufacturing process for the imprint mold 10.

[0028] For example, when the first concave-convex pattern portion 10P is formed by dry etching, the greater the damage to the surface of the first concave-convex pattern portion 10P caused by dry etching, the lower the composite elastic modulus and hardness measured by a microindentation test tend to be.

[0029] Furthermore, for example, the higher the applied power in dry etching, the greater the damage to the surface of the first concave-convex pattern portion 10P caused by dry etching. On the other hand, for example, the higher the pressure of the etching gas in dry etching, the shorter the mean free path of ions in the plasma, and therefore the less damage to the surface of the first concave-convex pattern portion 10P caused by dry etching.

[0030] Therefore, the composite elastic modulus and hardness measured by the microindentation test can be relatively decreased by increasing the applied power in the dry etching, or by decreasing the etching gas pressure in the dry etching, or by both. Conversely, the composite elastic modulus and hardness measured by the microindentation test can be relatively increased by decreasing the applied power in the dry etching, or by increasing the etching gas pressure in the dry etching, or by both.

[0031] For example, when the first concave-convex pattern 10P is formed by dry etching, the applied power in the dry etching is 50 W or more and 1000 W or less. For example, when the first concave-convex pattern 10P is formed by dry etching, the process pressure in the dry etching is 1 Pa or more and 10 Pa or less. For example, when the first concave-convex pattern 10P is formed by dry etching, the flow rate of the etching gas in the dry etching is 5 sccm or more and 100 sccm or less. When the material constituting the first concave-convex pattern 10P is single-crystal Si (silicon), the gas species used in the dry etching are, for example, CF4, CHF3, C2F6, SF6, Cl2, etc. Note that the etching conditions, including the etching gas species, are not limited to those described above, and may be any conditions that allow the first concave-convex pattern 10P to be formed.

[0032] (Micro-indentation test method) The microindentation test is performed by a nanoindentation method in accordance with ISO 14577. As an example, the method of the microindentation test employed in this embodiment will be described below.

[0033] In the microindentation test, a nanoindenter (product name: Hysitron TI-Premier, manufactured by Bruker Japan Co., Ltd.) was used as a measuring device for the composite elastic modulus and hardness. A Berkovich-type diamond indenter manufactured by Bruker Japan Co., Ltd. was used as the indenter.

[0034] The test was conducted in a 25°C environment by pressing the indenter to a depth of 100 nm at a rate of 100 nm / sec, holding the indenter at the maximum depth for 5 seconds, and then unloading at a rate of 100 nm / sec. This procedure was carried out at 30 measurement points. The 30 measurement points were selected so that the intervals between each measurement point were 100 μm or more.

[0035] As described above, the composite elastic modulus and hardness measured by the microindentation test in the imprint mold 10 are affected by the manufacturing process. Therefore, the measurement points to be subjected to the microindentation test were selected from among the surfaces of the first concave-convex pattern portion 10P that were affected by processing to form the pattern shape of the first concave-convex pattern portion 10P. For example, the bottom surface 12 of the first concave-convex pattern portion 10P is an example of a surface that was affected by processing to form the pattern shape of the first concave-convex pattern portion 10P.

[0036] Furthermore, the measurement points may be selected from areas other than the first concave-convex pattern 10P. For example, a test area that is exposed to dry etching in the manufacturing process of the imprint mold 10 may be provided outside the first concave-convex pattern 10P. In this case, the surface of the test area is affected by dry etching in the same way as the first concave-convex pattern 10P. In other words, the surface of such a test area is also an example of a surface that is affected by processing to form the pattern shape of the first concave-convex pattern 10P.

[0037] The composite elastic modulus and hardness were calculated from the data obtained by the above measurements. That is, the region of 60% to 95% of the maximum load at unloading in the unloading curve obtained by the above measurements was analyzed using the Oliver-Pharr method to calculate the composite elastic modulus and hardness. Similar measurements were also performed on fused quartz, which served as a standard sample, to obtain a correspondence relationship between the contact depth of the indenter on the test piece and the contact projected area. The measurement data for the test piece was then calibrated using this correspondence. In this embodiment, the composite elastic modulus and hardness of the first concave-convex pattern portion 10P of the imprint mold 10 were measured by performing a microindentation test using the above procedure.

[0038] (Operation of the first embodiment) In the first concave-convex pattern portion 10P, the first aspect ratio is determined by the characteristics required of the workpiece. For example, the workpiece manufactured by the imprint mold 10 may be a replica mold for manufacturing a diffractive optical element (DOE) used in an AR lens. In other words, the imprint mold 10 may be a master mold for manufacturing the replica mold.

[0039] In this case, a space pattern is formed as a primary transfer pattern, which is an inversion of the shape of the first concave-convex pattern portion 10P, on a replica mold manufactured using the imprint mold 10. Then, a line pattern is formed as a secondary transfer pattern, which is an inversion of the shape of the primary transfer pattern, on a diffractive optical element manufactured using the replica mold. The secondary transfer pattern is identical to the shape of the first concave-convex pattern portion 10P. That is, in this case, the first concave-convex pattern portion 10P of the imprint mold 10 is required to have a shape identical to the concave-convex pattern that satisfies the optical characteristics required of the diffractive optical element. Such optical elements may require a concave-convex pattern with a relatively high aspect ratio greater than 1.

[0040] In the imprint mold 10, as the first aspect ratio of the first concave-convex pattern portion 10P increases, the convex ribs 11 become more likely to break and be damaged. In particular, the greater the values ​​of the composite elastic modulus and hardness measured by a microindentation test in the first concave-convex pattern portion 10P, the more likely the convex ribs 11 become to break and be damaged.

[0041] Therefore, in the first embodiment, the composite elastic modulus of the first concave-convex pattern portion 10P measured by a micro-indentation test is set to 195 GPa or less. Also, the hardness of the first concave-convex pattern portion 10P measured by a micro-indentation test is set to 12 GPa or less. This makes it difficult for the ridges 11 to be damaged even if the first aspect ratio of the first concave-convex pattern portion 10P is greater than 1.

[0042] On the other hand, the smaller the values ​​of the composite elastic modulus and hardness measured by the micro-indentation test in the first concave-convex pattern portion 10P, the more easily the first concave-convex pattern portion 10P itself is deformed by the load when transferring the shape of the first concave-convex pattern portion 10P. Therefore, the smaller the values ​​of the composite elastic modulus and hardness measured by the micro-indentation test in the first concave-convex pattern portion 10P, the lower the dimensional accuracy of the transfer pattern transferred to the workpiece.

[0043] Therefore, in this embodiment, the first concave-convex pattern portion 10P has a composite elastic modulus measured by a microindentation test of 90 GPa or more. Also, the first concave-convex pattern portion 10P has a hardness measured by a microindentation test of 8 GPa or more. This prevents deterioration in the dimensional accuracy of the transfer pattern transferred to the workpiece.

[0044] The workpiece for the imprint mold 10 is not limited to a replica mold for producing a diffractive optical element applied to AR glasses. For example, the workpiece for the imprint mold 10 may be a diffractive optical element used in devices other than AR glasses, or a replica mold for producing an article having a line pattern other than a diffractive optical element. The workpiece for the imprint mold 10 may be any article other than a replica mold as long as it requires a space pattern as a transfer pattern.

[0045] (Effects of the first embodiment) (1-1) In the first uneven pattern portion 10P, by setting the composite elastic modulus measured by a micro-indentation test to 195 GPa or less, or the hardness measured by a micro-indentation test to 12 GPa or less, damage to the convex stripes 11 of the first uneven pattern portion 10P can be suppressed.

[0046] (1-2) In the first uneven pattern portion 10P, by setting the composite elastic modulus measured by a micro-indentation test to 90 GPa or more, or the hardness measured by a micro-indentation test to 8 GPa or more, the dimensional accuracy of the transfer pattern transferred to the workpiece can be ensured.

[0047] (1-3) The first concave-convex pattern portion 10P contains at least one selected from the group consisting of Si and a metal, and oxides, nitrides, and oxynitrides of Si or a metal. By forming the first concave-convex pattern portion 10P from such a material, the first concave-convex pattern portion 10P can be processed so that the composite elastic modulus of the first concave-convex pattern portion 10P measured by a microindentation test satisfies 90 GPa or more and 195 GPa or less. Similarly, by forming the first concave-convex pattern portion 10P from the above-mentioned material, the first concave-convex pattern portion 10P can be processed so that the hardness of the first concave-convex pattern portion 10P measured by a microindentation test satisfies 8 GPa or more and 12 GPa or less.

[0048] (Imprint mold 20 of second embodiment) An imprint mold 20 according to a second embodiment will be described with reference to FIG. 2, the imprint mold 20 of the second embodiment has a second concave-convex pattern portion 20P. The second concave-convex pattern portion 20P has a dot pattern. A hole pattern that is the inverse of the dot pattern of the second concave-convex pattern portion 20P is transferred to a workpiece by imprinting using the imprint mold 20.

[0049] The second concave-convex pattern portion 20P includes a plurality of unit shapes U2. Each unit shape U2 has a rectangular outer shape in a plan view from a viewpoint opposite to a plane including the first direction D1 and the second direction D2. In FIG. 2, the outer shape of the unit shape U2 is indicated by a two-dot chain line.

[0050] In the second concave-convex pattern portion 20P, the unit shapes U2 are aligned along the first direction D1 and the second direction D2. As an example, the unit shapes U2 are aligned repeatedly along the first direction D1 and the second direction D2 at a predetermined pitch P2. The pitch P2 is, for example, 500 nm or more and 10,000 nm or less. The pitch in the first direction D1 and the pitch in the second direction D2 may be different from each other.

[0051] The unit shape U2 has a protrusion 21 and a bottom surface 22. In the unit shape U2, the rectangular parallelepiped protrusion 21 is arranged so as to protrude from the bottom surface 22. As an example, in the unit shape U2, the protrusion 21 is located at the center in the first direction D1 and the center in the second direction D2, and the bottom surface 22 is located around the protrusion 21.

[0052] The protrusions 21 have a second line width W2 along the first direction D1. The protrusions 21 also have a second line width W2 along the second direction D2. That is, the protrusions 21 have the same second line width W2 in the first direction D1 and the second direction D2. The second line width W2 is, for example, 100 nm or more and 1000 nm or less in a cross-sectional view perpendicular to the second direction D2. Note that the width of the protrusions 21 in the first direction D1 and the width in the second direction D2 may be different from each other.

[0053] The second line width W2 may be, for example, the width of the base end of the protrusion 21, the width of the tip end of the protrusion 21, or the width of the midpoint between the base end and the tip end in a cross-sectional view perpendicular to the second direction D2. Furthermore, the second line width W2 may be, for example, the average value of the width of the base end and the width of the tip end in a cross-sectional view perpendicular to the second direction D2, or the average value of the width in the section from the base end to the tip end.

[0054] The protrusions 21 have a second height H2 along the third direction D3. The second height H2 corresponds to the distance from the base end to the tip end of the protrusions 21 in a cross-sectional view perpendicular to the second direction D2. For example, the second height H2 is 100 nm or more and 1000 nm or less in a cross-sectional view perpendicular to the second direction D2.

[0055] The protrusions 21 have a predetermined second aspect ratio in a cross-sectional view perpendicular to the second direction D2. The second aspect ratio is the ratio (H2 / W2) of the second height H2 to the second line width W2. The second aspect ratio is, for example, not less than 0.5 and not more than 2. That is, in the protrusions 21, the second line width W2 and the second height H2 are set so that the second aspect ratio falls within the range of not less than 0.5 and not more than 2.

[0056] The second concave-convex pattern portion 20P includes a portion having a composite elastic modulus of 90 GPa or more and 195 GPa or less as measured by a microindentation test, similar to the imprint mold 10 of the first embodiment. The second concave-convex pattern portion 20P also includes a portion having a hardness of 8 GPa or more and 12 GPa or less as measured by a microindentation test.

[0057] The second concave-convex pattern portion 20P can be made of the same material as the imprint mold 10 of the first embodiment. The imprint mold 20 of the second embodiment can be manufactured by the same manufacturing method as the imprint mold 10 of the first embodiment. In the second concave-convex pattern portion 20P of the second embodiment, the bottom surface 22 is an example of a surface affected by processing for forming the pattern shape of the second concave-convex pattern portion 20P. Therefore, in the imprint mold 20 of the second embodiment, the measurement point for the microindentation test is selected from the bottom surface 22. Alternatively, the measurement point for the microindentation test may be selected from a test region that is exposed to dry etching at a position outside the second concave-convex pattern portion 20P during the manufacturing process of the imprint mold 20.

[0058] (Operation of the second embodiment) In the second concave-convex pattern portion 20P, the second aspect ratio is determined by the characteristics required of the workpiece. For example, the workpiece manufactured by the imprint mold 20 may be a replica mold for manufacturing a metasurface having fine nanopillars such as a metalens. In other words, the imprint mold 20 may be a master mold for manufacturing the replica mold.

[0059] In this case, a hole pattern is formed as a primary transfer pattern, which is the inverse of the shape of the second concave-convex pattern portion 20P, in the replica mold manufactured using the imprint mold 20. Then, a dot pattern is formed as a secondary transfer pattern, which is the further inverse of the shape of the primary transfer pattern, in the metasurface manufactured using the replica mold. The secondary transfer pattern is equal to the shape of the second concave-convex pattern portion 20P. That is, in this case, the second concave-convex pattern portion 20P of the imprint mold 20 is required to have a shape equal to the concave-convex pattern that satisfies the optical characteristics required of the metasurface. Such a metasurface may require a concave-convex pattern with a relatively high aspect ratio greater than 1.

[0060] In the imprint mold 20, as the second aspect ratio of the second concave-convex pattern portion 20P increases, the convex portions 21 become more likely to break and be damaged. In particular, the larger the values ​​of the composite elastic modulus and hardness measured by the microindentation test in the second concave-convex pattern portion 20P, the more likely the convex portions 21 become to break and be damaged.

[0061] Therefore, in the second embodiment, similarly to the first embodiment, by controlling the upper limits of the composite elastic modulus and hardness measured by the micro-indentation test, the convex portions 21 are made less likely to be damaged even if the second aspect ratio of the second concave-convex pattern portion 20P becomes larger than 1. Furthermore, by controlling the composite elastic modulus and hardness measured by the micro-indentation test so that they do not fall below the lower limits, deterioration in the dimensional accuracy of the transfer pattern transferred to the workpiece is suppressed.

[0062] The workpiece of the imprint mold 20 is not limited to a replica mold for manufacturing a metasurface, but may be a replica mold for manufacturing an article having a dot pattern other than a metasurface.Furthermore, the workpiece of the imprint mold 20 is not limited to a replica mold, but may be another article requiring a hole pattern.

[0063] (Effects of the second embodiment) (2-1) In the second concave-convex pattern portion 20P, by setting the composite elastic modulus measured by a microindentation test to 195 GPa or less, or the hardness measured by a microindentation test to 12 GPa or less, damage to the convex portions 21 of the second concave-convex pattern portion 20P can be suppressed. Also, in the second embodiment, the same effects as those of (1-2) and (1-3) of the first embodiment can be obtained.

[0064] (Imprint mold 30 of the third embodiment) An imprint mold 30 according to a third embodiment will be described with reference to FIG. 3, the imprint mold 30 of the third embodiment includes a third concave-convex pattern portion 30P. The third concave-convex pattern portion 30P has a space pattern. A line pattern that is the inverse of the space pattern of the third concave-convex pattern portion 30P is transferred onto a workpiece by imprinting using the imprint mold 30.

[0065] The third concave-convex pattern portion 30P includes unit shapes U3 repeatedly arranged along the first direction D1 at a predetermined pitch P3. The pitch P3 is, for example, 500 nm or more and 10,000 nm or less. Each unit shape U3 includes a groove 31 extending in a second direction D2 intersecting the first direction D1 and a top surface 32. That is, the first direction D1 corresponds to the arrangement direction in which the multiple grooves 31 are arranged. The second direction D2 corresponds to the extension direction in which the grooves 31 extend.

[0066] The recessed ribs 31 have a rectangular cross-sectional shape in a cross section perpendicular to the second direction D2. The recessed ribs 31 have a bottom surface 31S. The bottom surface 31S is located at the bottom of the third uneven pattern portion 30P. The top surface 32 is located between the recessed ribs 31 of adjacent unit shapes U1. The top surface 32 is located at the top of the third uneven pattern portion 30P.

[0067] The grooves 31 have a third line width W3 along the first direction D1. For example, the third line width W3 is 100 nm or more and 1000 nm or less in a cross-sectional view perpendicular to the second direction D2. The third line width W3 may be, for example, the width of the bottom surface 31S of the grooves 31, the width of the opening of the grooves 31, or the width of the midpoint between the bottom surface 31S and the opening, in a cross-sectional view perpendicular to the second direction D2. Furthermore, the third line width W3 may be, for example, the average value of the width of the bottom surface 31S and the width of the opening, or the average value of the width in the section from the bottom surface 31S to the opening, in a cross-sectional view perpendicular to the second direction D2.

[0068] The third line width W3 of the recessed ribs 31 is equal to or smaller than the width (P3-W3) along the first direction D1 at the top surface 32 (W3≦P3-W3). The third line width W3 of the recessed ribs 31 is also sufficiently smaller than the length of the recessed ribs 31 extending in the second direction D2.

[0069] The grooves 31 have a first depth Z1 along the third direction D3. The first depth Z1 corresponds to the distance from the openings of the grooves 31 to the bottom surface 31S in a cross-sectional view perpendicular to the second direction D2. For example, the first depth Z1 is 100 nm or more and 1000 nm or less in a cross-sectional view perpendicular to the second direction D2.

[0070] The recessed ribs 31 have a predetermined third aspect ratio in a cross-sectional view perpendicular to the second direction D2. The third aspect ratio is the ratio (Z1 / W3) of the first depth Z1 to the third line width W3. The third aspect ratio is, for example, 0.5 or more and 2 or less. That is, in the recessed ribs 31, the third line width W3 and the first depth Z1 are set so that the third aspect ratio falls within the range of 0.5 or more and 2 or less.

[0071] As in the other embodiments, the third concave-convex pattern portion 30P includes a portion having a composite elastic modulus of 90 GPa to 195 GPa as measured by a microindentation test, and a portion having a hardness of 8 GPa to 12 GPa as measured by a microindentation test.

[0072] The third concave-convex pattern portion 30P can be made of the same material as in the other embodiments. The imprint mold 30 of the third embodiment can be manufactured by the same manufacturing method as in the other embodiments. In the third concave-convex pattern portion 30P of the third embodiment, the bottom surface 31S is an example of a surface affected by processing for forming the pattern shape of the third concave-convex pattern portion 30P. Therefore, in the imprint mold 30 of the third embodiment, the measurement point for the microindentation test is selected from the bottom surface 31S. Alternatively, the measurement point for the microindentation test may be selected from a test region exposed to dry etching at a position outside the third concave-convex pattern portion 30P during the manufacturing process of the imprint mold 30.

[0073] (Operation of the third embodiment) In the third concave-convex pattern portion 30P, the third aspect ratio is determined by the characteristics required of the workpiece. For example, the workpiece manufactured by the imprint mold 30 may be a diffractive optical element used in an AR lens.

[0074] In this case, a line pattern is formed on the diffractive optical element used in the AR lens as a transfer pattern that is the inverse of the shape of the third concave-convex pattern portion 30P of the imprint mold 30. In this case, the third concave-convex pattern portion 30P of the imprint mold 30 may be required to have a concave-convex pattern with a relatively high aspect ratio greater than 1 in order to satisfy the optical characteristics required of the diffractive optical element.

[0075] In the imprint mold 30, when the third aspect ratio of the third concave-convex pattern portion 30P is high, the aspect ratio of the transfer pattern transferred to the workpiece also becomes high, making the transfer pattern more susceptible to damage. In particular, the larger the values ​​of the composite elastic modulus and hardness measured by the microindentation test in the third concave-convex pattern portion 30P, the more susceptible the transfer pattern is to damage during mold release in the imprint method.

[0076] The phenomenon that the higher the rigidity of the third concave-convex pattern portion 30P, the more likely the transfer pattern is to be damaged is thought to be due to the following mechanism. When a pattern is transferred using the imprinting method, the third concave-convex pattern portion 30P is slightly deformed due to pressure applied to the third concave-convex pattern portion 30P. Then, when releasing the mold, the pressure on the third concave-convex pattern portion 30P is released, thereby releasing the deformation of the third concave-convex pattern portion 30P. At this time, a gap is generated between the third concave-convex pattern portion 30P and the imprinted resin, and the adhesion between the third concave-convex pattern portion 30P and the imprinted resin is released. This makes it easier to release the imprinted resin on which the transfer pattern has been formed.

[0077] On the other hand, when the rigidity of the third concave-convex pattern portion 30P is increased, the amount of deformation of the third concave-convex pattern portion 30P due to pressure during pattern transfer and the amount of deformation and recovery of the third concave-convex pattern portion 30P when the pressure is released during demolding are reduced. As a result, gaps are less likely to occur between the third concave-convex pattern portion 30P and the imprinted resin during demolding, so high adhesion between the third concave-convex pattern portion 30P and the imprinted resin is maintained. Therefore, a greater force is required to release the adhesion between the third concave-convex pattern portion 30P and the imprinted resin during demolding, and this force can easily damage the transfer pattern.

[0078] Therefore, in the third embodiment, the composite elastic modulus measured by the microindentation test in the third concave-convex pattern portion 30P is set to 195 GPa or less. Also, the hardness measured by the microindentation test in the third concave-convex pattern portion 30P is set to 12 GPa or less. This makes it difficult for the transfer pattern to be damaged even if the third aspect ratio of the third concave-convex pattern portion 30P becomes larger than 1.

[0079] Furthermore, in the third embodiment, as in the other embodiments, the composite elastic modulus and hardness measured by the microindentation test are controlled so as not to fall below the lower limit, thereby suppressing deterioration in the dimensional accuracy of the transfer pattern transferred to the workpiece.

[0080] The workpiece for the imprint mold 30 may be a diffractive optical element used in devices other than AR glasses, or any other article than a diffractive optical element, as long as it is an article that requires a line pattern as a transfer pattern.

[0081] (Effects of the third embodiment) (3-1) In the third concave-convex pattern portion 30P, by setting the composite elastic modulus measured by a microindentation test to 195 GPa or less, or the hardness measured by a microindentation test to 12 GPa or less, damage to the transfer pattern transferred to the workpiece can be suppressed. Also, in the third embodiment, the same effects as those of (1-2) and (1-3) in the first embodiment can be obtained.

[0082] (Imprint mold 40 of the fourth embodiment) An imprint mold 40 according to a fourth embodiment will be described with reference to FIG. 4, the imprint mold 40 of the fourth embodiment includes a fourth concave-convex pattern portion 40P. The fourth concave-convex pattern portion 40P has a hole pattern. A dot pattern that is the inverse of the hole pattern of the fourth concave-convex pattern portion 40P is transferred to a workpiece by imprinting using the imprint mold 40.

[0083] The fourth concave-convex pattern portion 40P includes a plurality of unit shapes U4. Each unit shape U4 has a rectangular outer shape when viewed from a viewpoint opposite to a plane including the first direction D1 and the second direction D2. In FIG. 4, the outer shape of the unit shape U4 is indicated by a two-dot chain line.

[0084] In the fourth concave-convex pattern portion 40P, the unit shapes U4 are aligned along the first direction D1 and the second direction D2. As an example, the unit shapes U4 are aligned repeatedly along the first direction D1 and the second direction D2 at a predetermined pitch P4. The pitch P4 is, for example, 500 nm or more and 10,000 nm or less. The pitch in the first direction D1 and the pitch in the second direction D2 may be different from each other.

[0085] The unit shape U4 has a recess 41 and a top surface 42. In the unit shape U4, the rectangular parallelepiped recess 41 is arranged so as to be recessed from the top surface 42. As an example, in the unit shape U4, the recess 41 is located at the center in the first direction D1 and the center in the second direction D2, and the top surface 42 is located around it. The recess 41 has a bottom surface 41S. The bottom surface 41S is located at the bottom of the fourth uneven pattern portion 40P.

[0086] The recess 41 has a fourth line width W4 along the first direction D1. The recess 41 also has a fourth line width W4 along the second direction D2. That is, the recess 41 has the same fourth line width W4 in the first direction D1 and the second direction D2. As an example, the fourth line width W4 is 100 nm or more and 1000 nm or less in a cross-sectional view perpendicular to the second direction D2. Note that the width of the recess 41 in the first direction D1 and the width in the second direction D2 may be different from each other.

[0087] The fourth line width W4 may be, for example, the width of the bottom surface 41S of the recess 41 in a cross-sectional view perpendicular to the second direction D2, the width of the opening of the recess 41, or the width of the midpoint between the bottom surface 41S and the opening. Furthermore, the fourth line width W4 may be, for example, the average value of the width of the bottom surface 41S and the width of the opening in a cross-sectional view perpendicular to the second direction D2, or the average value of the width in the section from the bottom surface 41S to the opening.

[0088] The recess 41 has a second depth Z2 along the third direction D3. The second depth Z2 corresponds to the distance from the opening of the recess 41 to the bottom surface 41S in a cross-sectional view perpendicular to the second direction D2. For example, the second depth Z2 is 100 nm or more and 1000 nm or less in a cross-sectional view perpendicular to the second direction D2.

[0089] The recess 41 has a predetermined fourth aspect ratio in a cross-sectional view perpendicular to the second direction D2. The fourth aspect ratio is the ratio (Z2 / W4) of the second depth Z2 to the fourth line width W4. The fourth aspect ratio is, for example, not less than 0.5 and not more than 2. That is, in the recess 41, the fourth line width W4 and the second depth Z2 are set so that the fourth aspect ratio falls within the range of not less than 0.5 and not more than 2.

[0090] The fourth concave-convex pattern portion 40P includes a portion having a composite elastic modulus of 90 GPa or more and 195 GPa or less as measured by a microindentation test, similar to the imprint mold 10 of the first embodiment. The fourth concave-convex pattern portion 40P also includes a portion having a hardness of 8 GPa or more and 12 GPa or less as measured by a microindentation test.

[0091] The fourth concave-convex pattern portion 40P can be made of the same material as the imprint mold 10 of the first embodiment. The imprint mold 40 of the fourth embodiment can be manufactured by the same manufacturing method as the imprint mold 10 of the first embodiment. In the fourth concave-convex pattern portion 40P of the fourth embodiment, the bottom surface 41S is an example of a surface affected by processing for forming the pattern shape of the fourth concave-convex pattern portion 40P. Therefore, in the imprint mold 40 of the fourth embodiment, the measurement point for the microindentation test is selected from the bottom surface 41S. Alternatively, the measurement point for the microindentation test may be selected from a test region exposed to dry etching at a position outside the fourth concave-convex pattern portion 40P during the manufacturing process of the imprint mold 40.

[0092] (Operation of the fourth embodiment) In the fourth concave-convex pattern portion 40P, the fourth aspect ratio is determined by the characteristics required of the workpiece. For example, the workpiece manufactured by the imprint mold 40 may be a master mold for manufacturing a metasurface having fine nanopillars, such as a metalens.

[0093] In this case, a dot pattern is formed on the metasurface as a primary transfer pattern that is the inverse of the shape of the fourth concave-convex pattern portion 40P. In this case, the fourth concave-convex pattern portion 40P of the imprint mold 40 may be required to have a concave-convex pattern with a relatively high aspect ratio greater than 1 in order to satisfy the optical characteristics required of the metasurface.

[0094] In the imprint mold 40, the transfer pattern becomes more susceptible to damage when the second aspect ratio of the second concave-convex pattern portion 20P becomes higher. In particular, in the fourth concave-convex pattern portion 40P, the greater the values ​​of the composite elastic modulus and hardness measured by the microindentation test, the more susceptible the transfer pattern becomes to damage during mold release in the imprint method.

[0095] Therefore, in the fourth embodiment, similar to the third embodiment, the composite elastic modulus and hardness measured by the microindentation test are controlled so as not to exceed their upper limits, thereby suppressing damage to the transfer pattern during demolding even when the fourth aspect ratio is greater than 1. Furthermore, the composite elastic modulus and hardness measured by the microindentation test are controlled so as not to fall below their lower limits, thereby suppressing deterioration in the dimensional accuracy of the transfer pattern transferred to the workpiece. Note that the workpiece for the imprint mold 40 may be any article other than a metasurface, as long as it requires a dot pattern as the transfer pattern.

[0096] (Effects of the fourth embodiment) (4-1) In the fourth concave-convex pattern portion 40P, by setting the composite elastic modulus measured by a microindentation test to 195 GPa or less, or the hardness measured by a microindentation test to 12 GPa or less, damage to the transfer pattern transferred to the workpiece can be suppressed. Also, in the fourth embodiment, the same effects as those of (1-2) and (1-3) of the first embodiment can be obtained.

[0097] (Example of change) The above first to fourth embodiments can be modified as follows. The following modifications can be combined with each other as long as they are not technically inconsistent. In the following, when the first concave-convex pattern portion 10P, the second concave-convex pattern portion 20P, the third concave-convex pattern portion 30P, and the fourth concave-convex pattern portion 40P in each embodiment are not to be distinguished from one another, they will be simply referred to as concave-convex pattern portions.

[0098] In the first to fourth embodiments, the concave-convex pattern portion may have a release layer on its surface. The release layer is a layer having a lower surface energy than the material constituting the concave-convex pattern portion. As an example, the release layer is made of a fluoropolymer. Specifically, a solution of a silane coupling agent is applied to the surface of the concave-convex pattern portion to form a film made of a fluoropolymer having a low surface energy on the surface of the concave-convex pattern portion. In this way, by providing a release layer, it is possible to suppress release defects of the imprinted resin as the workpiece. Note that the release layer is a film that is sufficiently thin compared to the indentation depth of the microindentation test. Therefore, the influence of the release layer on the microindentation test can be ignored.

[0099] In the first to fourth embodiments, the material of the concave-convex pattern portion is not limited as long as it is a material that can satisfy the above-mentioned numerical ranges for the composite elastic modulus and hardness measured by a microindentation test after being processed to form the pattern shape of the concave-convex pattern portion. That is, the material of the concave-convex pattern portion may be an inorganic material other than Si and metal, such as a resin material.

[0100] In the first to fourth embodiments, the concave-convex pattern portion may be configured such that at least one of the composite elastic modulus and hardness measured by a microindentation test falls within the above-described numerical range. For example, if the composite elastic modulus of the concave-convex pattern portion measured by a microindentation test is 90 GPa or more and 195 GPa or less, the hardness measured by the microindentation test may be less than 8 GPa or more than 12 GPa. Furthermore, if the hardness measured by the microindentation test is 8 GPa or more and 12 GPa or less, the composite elastic modulus measured by the microindentation test may be less than 90 GPa or more than 195 GPa.

[0101] (Test example) Test examples using the imprint molds 10, 20, 30, and 40 of the respective embodiments will be described below with reference to Figures 5 to 8. Note that the following test examples are examples for illustrating the effects of the above embodiments, and do not limit the present disclosure.

[0102] In the following test examples, samples a1 to a21 shown in Fig. 5, samples b1 to b21 shown in Fig. 6, samples c1 to c21 shown in Fig. 7, and samples d1 to d21 shown in Fig. 8 were prepared. The material of the concave-convex pattern portion was single crystal Si in all samples.

[0103] (Samples a1 to a21) As shown in FIG. 5, the samples a1 to a21 were shaped to include a first concave-convex pattern portion 10P having ridges 11, like the imprint mold 10 of the first embodiment.

[0104] For samples a1 to a21, the composite elastic modulus and hardness measured by a microindentation test were adjusted to seven levels by changing the etching conditions in the manufacturing process of the imprint mold 10. For samples a1 to a3, the composite elastic modulus was set to 210 GPa and the hardness was set to 13 GPa. For samples a4 to a6, the composite elastic modulus was set to 195 GPa and the hardness was set to 12 GPa. For samples a7 to a9, the composite elastic modulus was set to 185 GPa and the hardness was set to 12 GPa. For samples a10 to a12, the composite elastic modulus was set to 132 GPa and the hardness was set to 10 GPa. For samples a13 to a15, the composite elastic modulus was set to 90 GPa and the hardness was set to 8 GPa. For samples a16 to a18, the composite elastic modulus was set to 80 GPa and the hardness was set to 7 GPa. In the samples a19 to a21, the composite elastic modulus was set to 72 GPa and the hardness was set to 6 GPa.

[0105] Furthermore, for samples a1 to a21, the first line width W1 of the ridges 11 was adjusted to three levels: 250 nm, 500 nm, and 1000 nm, for each level of composite elastic modulus and hardness measured by the microindentation test. Furthermore, for samples a1 to a21, the first height H1 of the ridges 11 was set to 500 nm. That is, for samples a1 to a21, the first line width W1 of the ridges 11 was changed to adjust the first aspect ratio to three levels: 2, 1, and 0.5.

[0106] (Samples b1 to b21) As shown in FIG. 6, samples b1 to b21 were shaped to include a second concave-convex pattern portion 20P having convex portions 21, like the imprint mold 20 of the second embodiment.

[0107] For samples b1 to b21, the composite elastic modulus and hardness measured by the microindentation test were adjusted to seven levels, similar to samples a1 to a21, by changing the etching conditions in the manufacturing process of the imprint mold 20. Furthermore, for samples b1 to b21, the second line width W2 of the convex portions 21 was adjusted to three levels, 250 nm, 500 nm, and 1000 nm, similar to samples a1 to a21, for each level of the composite elastic modulus and hardness measured by the microindentation test. Furthermore, for samples b1 to b21, the second height H2 of the convex portions 21 was set to 500 nm. That is, for samples b1 to b21, the second line width W2 of the convex portions 21 was changed, thereby adjusting the second aspect ratio to three levels, 2, 1, and 0.5.

[0108] (Samples c1 to c21) As shown in FIG. 7, samples c1 to c21 were shaped to include a third concave-convex pattern portion 30P having concave stripes 31, like the imprint mold 30 of the third embodiment.

[0109] For samples c1 to c21, the composite elastic modulus and hardness measured by the microindentation test were adjusted to seven levels, similar to samples a1 to a21, by changing the etching conditions in the manufacturing process of the imprint mold 30. Furthermore, for samples c1 to c21, the third line width W3 of the recessed streaks 31 was adjusted to three levels, 250 nm, 500 nm, and 1000 nm, similar to samples a1 to a21, for each level of the composite elastic modulus and hardness measured by the microindentation test. Furthermore, for samples c1 to c21, the first depth Z1 of the recessed streaks 31 was set to 500 nm. That is, for samples c1 to c21, the third aspect ratio was adjusted to three levels, 2, 1, and 0.5, by changing the third line width W3 of the recessed streaks 31.

[0110] (Samples d1 to d21) As shown in FIG. 8, samples d1 to d21 were shaped to include a fourth concave-convex pattern portion 40P having recesses 41, like the imprint mold 40 of the fourth embodiment.

[0111] For samples d1 to d21, the composite elastic modulus and hardness measured by the microindentation test were adjusted to seven levels, similar to samples a1 to a21, by changing the etching conditions in the manufacturing process of the imprint mold 40. Furthermore, for samples d1 to d21, the fourth line width W4 of the recess 41 was adjusted to three levels, 250 nm, 500 nm, and 1000 nm, similar to samples a1 to a21, for each level of the composite elastic modulus and hardness measured by the microindentation test. Furthermore, for samples d1 to d21, the second depth Z2 of the recess 41 was set to 500 nm. That is, for samples d1 to d21, the fourth aspect ratio was adjusted to three levels, 2, 1, and 0.5, by changing the fourth line width W4 of the recess 41.

[0112] For Samples a1 to a21, b1 to b21, c1 to c21, and d1 to d21, the measurement points for the microindentation test were selected from a test area located outside the concave-convex pattern. The test area was an area from which the resist material was removed during the formation of the concave-convex pattern so as to be exposed to dry etching. In other words, the surface of the test area was affected by dry etching in the same way as the surface of the concave-convex pattern. Furthermore, the same etching conditions were applied to samples with the same levels of composite modulus and hardness measured by the microindentation test.

[0113] (evaluation) The evaluation procedure was as follows: first, the shape of the concave-convex pattern was transferred to the imprint resin once using each of the prepared samples. After the transfer was completed, the presence or absence of damage in the concave-convex pattern of each sample, the presence or absence of damage in the transfer pattern transferred to the imprint resin, and the dimensional accuracy of the transfer pattern were evaluated.

[0114] The presence or absence of damage in the concave-convex pattern portion of each sample and the presence or absence of damage in the transfer pattern transferred to the imprint resin were determined by observation using a scanning electron microscope (SEM). The dimensional accuracy of the transfer pattern was evaluated by measuring two dimensions: the line width and the height or depth of the concave-convex pattern portion. The dimensions were measured using a scanning probe microscope (Hitachi High-Tech Corporation) in a cross-sectional view perpendicular to the second direction D2. A sample was evaluated as "good" if the difference between the dimensions of the transfer pattern transferred to the imprint resin and the concave-convex pattern portion was less than 5% at both measurement points, based on the dimensions of the concave-convex pattern portion on the mold. A sample was evaluated as "poor" if the difference between the dimensions of the transfer pattern transferred to the imprint resin and the concave-convex pattern portion was 5% or more at either measurement point, based on the dimensions of the concave-convex pattern portion on the mold. The evaluation results are shown in Figures 5 to 8.

[0115] The evaluation results of each sample will be described with reference to Figures 5 to 8. First, the evaluation results of samples a4 to a15, b4 to b15, c4 to c15, and d4 to d15, which had a composite elastic modulus of 90 GPa to 195 GPa and a hardness of 8 GPa to 12 GPa, will be described. In these samples, no damage was observed to the concave-convex pattern portion or the transferred pattern, and the difference between the dimensions of the concave-convex pattern portion and the transferred pattern was less than 5% of the dimensions of the concave-convex pattern portion.

[0116] Next, we will explain the evaluation results of samples a16 to a21, b16 to b21, c16 to c21, and d16 to d21, which had a composite modulus of elasticity of less than 90 GPa and a hardness of less than 8 GPa. In these samples, no damage to the concave-convex pattern or the transferred pattern was observed, but the difference between the dimensions of the concave-convex pattern and the transferred pattern was 5% or more of the dimensions of the concave-convex pattern. Therefore, it was confirmed that the dimensional accuracy of the concave-convex pattern can be ensured by setting the composite modulus to 90 GPa or more or the hardness to 8 GPa or more.

[0117] Next, the evaluation results of samples a1 to a3 and b1 to b3, which have ridges 11 or ridges 21 and a composite elastic modulus of more than 195 GPa and a hardness of more than 12 GPa, will be described. In these samples, no damage to the transferred pattern was observed, and the difference between the dimensions of the concave-convex pattern and the dimensions of the transferred pattern was less than 5% of the dimensions of the concave-convex pattern. On the other hand, damage to the concave-convex pattern was observed in samples a1 and b1, which had an aspect ratio of 2. Therefore, it was confirmed that, in a concave-convex pattern having ridges 11 or ridges 21, by setting the composite elastic modulus to 195 GPa or less or the hardness to 12 GPa or less, damage to the concave-convex pattern can be suppressed even when the aspect ratio is greater than 1.

[0118] Next, we will explain the evaluation results of samples c1 to c3 and d1 to d3, which have grooves 31 or depressions 41 and a composite elastic modulus of more than 195 GPa and a hardness of more than 12 GPa. In these samples, no damage to the concave-convex pattern was observed. On the other hand, in samples c1 and d1, which had an aspect ratio of 2, damage to the transfer pattern transferred to the imprint resin was confirmed. It should be noted that dimensional accuracy could not be measured for samples c1 and d1. Therefore, it was confirmed that by setting the composite elastic modulus to 195 GPa or less or the hardness to 12 GPa or less in the concave-convex pattern having grooves 31 or depressions 41, damage to the transfer pattern can be suppressed even when the aspect ratio is greater than 1. [Explanation of symbols]

[0119] D1…first direction D2…Second direction H1...First height H2: Second height U1, U2, U3, U4...Unit shape W1: First line width W2: Second line width W3: Third line width W4: Fourth line width 10, 20, 30, 40...Imprint mold 10P...First uneven pattern section 11...Convex strip 12, 22, 31S, 41S...Bottom 20P: Second uneven pattern section 21...Convex part 30P...Third uneven pattern part 31...concave line 40P...4th uneven pattern part 41...recess

Claims

1. An imprint mold having a concave-convex pattern portion, In the concave-convex pattern portion, the composite elastic modulus measured by a microindentation test is 90 GPa or more and 195 GPa or less. Imprint mold.

2. An imprint mold having a concave-convex pattern portion, The concave-convex pattern portion has a hardness of 8 GPa or more and 12 GPa or less as measured by a microindentation test. Imprint mold.

3. The material of the concave-convex pattern portion includes at least one selected from the group consisting of Si, metal, and oxide, nitride, and oxynitride of Si or metal. The imprint mold according to claim 1 or 2.

4. the concave-convex pattern portion has a line pattern including a plurality of convex stripes extending in an extension direction, the plurality of convex stripes being arranged along an arrangement direction intersecting the extension direction, Each of the protrusions has a first line width of 1000 nm or less in a cross section perpendicular to the extending direction, and the ratio of the height of the protrusion to the first line width is 2 or less. The imprint mold according to claim 1 or 2.

5. the concave-convex pattern portion has a dot pattern including a plurality of convex portions arranged along a first direction and a second direction intersecting the first direction, Each of the protrusions has a second line width of 1000 nm or less in a cross section perpendicular to the second direction, and the ratio of the height of the protrusion to the second line width is 2 or less. The imprint mold according to claim 1 or 2.

6. the concave-convex pattern portion has a space pattern including a plurality of concave stripes extending in an extension direction, the plurality of concave stripes being aligned along an arrangement direction intersecting the extension direction, Each of the recesses has a third line width of 1000 nm or less in a cross section perpendicular to the extending direction, and the ratio of the depth of the recess to the third line width is 2 or less. The imprint mold according to claim 1 or 2.

7. the concave-convex pattern portion has a hole pattern including a plurality of concave portions arranged along a first direction and a second direction intersecting the first direction, Each recess has a fourth line width of 1000 nm or less in a cross section perpendicular to the second direction, and the ratio of the depth of the recess to the fourth line width is 2 or less. The imprint mold according to claim 1 or 2.

8. The concave-convex pattern portion has a release layer on the surface thereof. The imprint mold according to claim 1 or 2.

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