Imprint mold and template manufacturing method and drawing system

Abstract

To provide a method for manufacturing an imprint mold with which a template having a desired transfer uneven pattern can be manufactured with high accuracy.SOLUTION: A method for manufacturing an imprint mold includes steps of: determining a first positional deviation component that is a linear positional deviation component of a first uneven pattern from a first positional deviation amount; determining a first residual component that is a nonlinear positional deviation component of the first uneven pattern from the first positional deviation amount and the first positional deviation component; determining a second positional deviation component that is a linear positional deviation component of a second uneven pattern from a second positional deviation amount; determining a second residual component that is a nonlinear positional deviation component of the second uneven pattern from the second positional deviation amount and the second positional deviation component; and determining a correction value for correcting pattern data from a difference between the first residual component and the second residual component.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to methods of manufacturing imprint molds and templates, and imaging systems. [Background technology]

[0002] Nanoimprint technology, a microfabrication technology, is a pattern formation technology that uses a mold member (imprint mold, hereinafter sometimes simply referred to as "mold") having a fine concave-convex pattern formed on the surface of a base material, and transfers the fine concave-convex pattern to a workpiece, thereby transferring the fine concave-convex pattern at the same size (see Patent Document 1).

[0003] A mold having a fine concave-convex pattern used in such nanoimprinting technology can be manufactured, for example, by electron beam (EB) lithography, etc. A mold manufactured in this manner has a high degree of precision in the shape and dimensions of the fine concave-convex pattern, but the manufacturing cost is high, and after a certain number of transfer steps, defects may occur in the transfer pattern formed on the workpiece (such as the imprinting resin) or the fine concave-convex pattern of the mold may be damaged.

[0004] If defects in the transfer pattern or damage to the fine unevenness pattern of the mold occurs in this way, replacing the mold with a new one will lead to increased manufacturing costs for products manufactured through the nanoimprint process. Therefore, when performing a nanoimprint process on an industrial scale, generally, a mold manufactured by electron beam (EB) lithography or the like as described above is used as a master mold (hereinafter sometimes referred to as a "first mold"), and a large number of replica molds (hereinafter sometimes referred to as a "second mold") made by nanoimprint lithography using the first mold, or a large number of replica molds (hereinafter sometimes referred to as a "third mold") replicated by nanoimprint lithography using the second mold are used as imprint molds in the nanoimprint process (see Patent Document 2).

[0005] The numerous second and third molds obtained in this manner can be mass-produced at low cost. Therefore, by using them as imprint molds in a nanoimprint process, even if the imprint mold is damaged, the nanoimprint process can be carried out while successively replacing the molds, and products having fine concave-convex patterns can be manufactured at low cost. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] U.S. Patent No. 5,772,905 [Patent Document 2] JP 2010-282995 A Summary of the Invention [Problem to be solved by the invention]

[0007] The replica mold is obtained by using nanoimprinting technology, which is a pattern forming technology that transfers a fine concave-convex pattern at the same size based on the master mold. Therefore, the arrangement of each fine concave-convex pattern in the master mold (the position of each fine concave-convex pattern on the pattern forming surface (the surface on which the fine concave-convex pattern is formed) of the mold) is usually designed to be the same as or a mirror-inverted arrangement of each fine concave-convex pattern in the replica mold (the position of the fine concave-convex pattern in the design pattern data) depending on the number of imprint processes from the master mold to the replica mold. For example, if the number of imprint processes is an odd number, the arrangement of each fine concave-convex pattern in the master mold is designed to be a mirror-inverted arrangement of each fine concave-convex pattern in the replica mold. On the other hand, if the number of imprint processes is an even number, the arrangement of each fine concave-convex pattern in the master mold is designed to be the same as the arrangement of each fine concave-convex pattern in the replica mold.

[0008] However, at least some of the multiple fine concave-convex patterns included in the replica mold (second mold, etc.) may be displaced from the position where they should be formed (the position of each fine concave-convex pattern in the design pattern data of the replica mold). This positional displacement of the fine concave-convex patterns is thought to be caused by various influences, such as differences in density of the fine concave-convex patterns in the pattern-forming surface of the mold, deformation of the mold or base material during imprinting, and stress generated in the imprinting resin when the mold is released from the imprinting resin. In particular, when the replica mold is produced through a nanoimprint lithography process having multiple stages, the amount of positional displacement caused by each nanoimprint lithography process is accumulated, and the amount of positional displacement of the fine concave-convex patterns in the replica mold finally produced may become significantly larger than the allowable range.

[0009] If the positional deviation of the fine concave-convex pattern in the replica mold occurs in this way, there is a problem in that the fine concave-convex pattern to be formed by a nanoimprint process using the replica mold will be shifted from a desired position.

[0010] On the other hand, some imprinting devices using the replica mold have a pattern position correction mechanism that can change the position of each fine concave-convex pattern in the pattern formation surface of the mold by deforming the mold, and can perform the nanoimprinting process with the position of the fine concave-convex pattern changed. By using such an imprinting device, even a replica mold in which the fine concave-convex pattern has some positional deviation can be used in the nanoimprinting process. However, if the amount of positional deviation of the fine concave-convex pattern in the replica mold exceeds the amount by which the position of the fine concave-convex pattern can be changed by the pattern position correction mechanism of the imprinting device (the amount by which the position of the fine concave-convex pattern can be changed differs depending on the imprinting device, but is generally about 1 to 5 ppm), the same problem as described above still occurs.

[0011] Moreover, the pattern position correction mechanism in the above-mentioned imprinting apparatus is generally composed of an actuator such as a piezoelectric element capable of applying pressure to the side surface of a mold having a rectangular shape in plan view, and corrects the position of the fine concave-convex pattern in one direction (e.g., X direction) and / or a direction perpendicular thereto (e.g., Y direction) by applying pressure to the side surface of the mold and contracting the mold. That is, by using the pattern position correction mechanism in the above-mentioned imprinting apparatus, the position of the entire fine concave-convex pattern in the replica mold can be corrected toward the center of the replica mold (the geometric center of the surface having the pattern formation surface). However, the positional deviation direction of the fine concave-convex pattern in the replica mold is not necessarily a fixed direction, and if the positional deviation direction of each fine concave-convex pattern is in an indefinite direction, there are cases where the pattern position correction mechanism in the above-mentioned imprinting apparatus cannot correct the fine concave-convex pattern in the replica mold to an appropriate position, which causes a problem of lack of versatility.

[0012] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a method for manufacturing an imprint mold capable of producing a template having a desired transferred concave-convex pattern with high precision, a method for manufacturing a template using the imprint mold, and a drawing system for manufacturing the imprint mold. [Means for solving the problem]

[0013] In order to achieve such an object, the present disclosure provides a method for manufacturing an imprint mold having a concave-convex pattern, the imprint mold being used for producing a template having a transferred concave-convex pattern by transferring the concave-convex pattern, and the manufacturing method includes: Design About design A step of producing a first mold having a first concave-convex pattern based on pattern data, and a step of producing a second mold having a second concave-convex pattern through an imprint process using the first mold; designPattern data and the first concave-convex pattern The first measured pattern data determining a first positional deviation amount of the first concave-convex pattern which is deviated from a position where the concave-convex pattern is to be formed in the imprint mold; and A least squares method using a polynomial that represents the first positional deviation amount is performed. a step of determining a first positional deviation component which is a linear positional deviation component of the first concave-convex pattern; and a step of determining a nonlinear positional deviation component of the first concave-convex pattern from the first positional deviation amount and the first positional deviation component, a difference between the first positional deviation amount and the first positional deviation component, a step of obtaining a first residual component, Design About design Transferred uneven pattern data and the second uneven pattern The second measured pattern data and determining a second positional deviation amount of the second concave-convex pattern which is shifted from a position where the transferred concave-convex pattern of the template is to be formed, and A least squares method using a polynomial that represents the second positional deviation amount is performed. a step of determining a second positional deviation component which is a linear positional deviation component of the second concave-convex pattern; and a step of determining a nonlinear positional deviation component of the second concave-convex pattern from the second positional deviation amount and the second positional deviation component, a difference between the second positional deviation amount and the second positional deviation component, a step of calculating a second residual component from the difference between the first residual component and the second residual component, a step of calculating a correction value for correcting the pattern data from the difference between the first residual component and the second residual component, a step of generating corrected pattern data by correcting the pattern data based on the correction value, and a step of producing the imprint mold having the concave-convex pattern based on the corrected pattern data. The present invention provides a method for manufacturing an imprint mold, comprising:

[0014] In the step of obtaining the correction value, a third positional deviation component corresponding to the correction value may be obtained by using an approximation polynomial that represents a difference between the first residual component and the second residual component, and the correction value may be obtained based on the third positional deviation component. The correction value may be a value calculated from the approximation polynomial by using a value obtained by inverting the sign of the third positional deviation component, and the approximation polynomial may be composed of a quadratic term and a cubic term. The correction value may be calculated by Uniformly at a specified magnification Reduced A step of obtaining a reduction correction value,The pattern data is corrected based on the value to obtain the corrected pattern data. Generate You may do so.

[0015] The second mold may be fabricated through an imprint process using the first mold, the second misalignment component and the second residual component may be obtained for each of the second molds, and the correction value may be obtained from a difference between the first residual component and an average value of the second residual components; the first molds may be fabricated based on the pattern data, the second molds may be fabricated through an imprint process using each of the first molds, the first misalignment component and the first residual component may be obtained for each of the first molds, the second misalignment component and the second residual component may be obtained for each of the second molds, and the correction value may be obtained from a difference between an average value of the first residual components and an average value of the second residual components; and when an apparatus for performing the imprint process is the same, pattern data relating to another concave-convex pattern may be corrected based on the correction value. The imprint mold may be used to fabricate the template using an imprint apparatus used in the imprint process in the step of fabricating the second mold.

[0016] The present disclosure provides a method for manufacturing the template using the above-mentioned imprint mold, the method including a template substrate preparation step of preparing a template substrate having a first surface and a second surface opposite to the first surface, an imprinting step of supplying an imprint resin onto the first surface of the template substrate and pressing the concave-convex pattern of the imprint mold against the imprint resin to form a transfer pattern, and an etching step of etching the template substrate using the transfer pattern as a mask, wherein the imprinting step forms the transfer pattern using the imprint apparatus.

[0017] The present disclosure provides a method for manufacturing an imprint mold having a different type of concave-convex structure from the concave-convex pattern of the imprint mold, wherein the imprint mold is used to produce a template having a transferred concave-convex structure to which the concave-convex structure is transferred, the method including a step of correcting design data relating to the concave-convex structure based on the correction value to generate corrected design data, and a step of producing the imprint mold having the concave-convex structure based on the corrected design data, wherein the imprint mold having the concave-convex structure is used to produce the template having the transferred concave-convex structure using an imprint apparatus used in the imprint process in the step of producing the second mold.

[0018] The present disclosure also relates to a drawing system for use in manufacturing an imprint mold having a concave-convex pattern, which is used to produce a template having a transferred concave-convex pattern by transferring the concave-convex pattern, the drawing system including a drawing device for forming a pattern latent image on a mold substrate for manufacturing the imprint mold, and a correction pattern data for forming the pattern latent image, which is transferred to the concave-convex pattern. Design About design and a pattern data correction device for correcting and generating pattern data, the pattern data correction device comprising: design A first concave-convex pattern of a first mold produced based on the pattern data The first measured pattern data and the above design Based on the pattern data, the first concave-convex pattern is determined to be misaligned from a position where the concave-convex pattern is to be formed in the imprint mold. A first positional deviation amount is calculated. The first misalignment component is a linear misalignment component. is calculated by a least squares method using a polynomial that indicates the first positional deviation amount, The first residual component, which is a nonlinear position shift component a difference between the first positional deviation amount and the first positional deviation component and a second concave-convex pattern of a second mold produced by an imprint process using the first mold. The second measured pattern data and the transferred uneven pattern Design About designThe second concave-convex pattern, which is displaced from the position where the transferred concave-convex pattern is to be formed in the template, is determined based on the transfer pattern data. A second positional deviation amount is calculated. The second misalignment component is a linear misalignment component. is calculated by a least squares method using a polynomial that indicates the second positional deviation amount, The second residual component is a nonlinear position shift component. a difference between the second positional deviation amount and the second positional deviation component a positional deviation component generation unit that calculates a correction value for correcting the pattern data from a difference between the first residual component and the second residual component, and a corrected pattern data generation unit that generates the corrected pattern data based on the correction value, wherein the drawing apparatus provides a drawing system that forms the pattern latent image on the mold substrate based on the corrected pattern data. Effect of the Invention

[0019] The present disclosure can provide a method for manufacturing an imprint mold capable of manufacturing a template having a desired transferred concave-convex pattern with high precision, a method for manufacturing a template using the imprint mold, and a drawing system for manufacturing the imprint mold. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a flow chart illustrating steps in a method for manufacturing an imprint mold according to one embodiment of the present disclosure. [Figure 2A] FIG. 2A is an enlarged, partially cut-away end view that illustrates a schematic diagram of a step of an exemplary method for making a first mold in an embodiment of the present disclosure. [Figure 2B] FIG. 2B is an enlarged, partially cut-away end view that generally illustrates a step in an exemplary method for producing a first mold according to an embodiment of the present disclosure, the step being subsequent to the step illustrated in FIG. 2A. [Figure 2C] FIG. 2C is an enlarged, partially cut-away end view that generally illustrates a step in an exemplary method for producing a first mold according to an embodiment of the present disclosure, the step following the step illustrated in FIG. 2B. [Figure 2D]FIG. 2D is an enlarged, partially cut-away end view that generally illustrates a step in an exemplary method for producing a first mold according to an embodiment of the present disclosure, the step following the step illustrated in FIG. 2C. [Figure 3A] FIG. 3A is an enlarged, partially cut-away end view that illustrates a schematic diagram of a step of an exemplary method for producing a second mold in an embodiment of the present disclosure. [Figure 3B] FIG. 3B is an enlarged, partially cut-away end view that generally illustrates a step in an exemplary method for producing a second mold according to an embodiment of the present disclosure, the step following the step illustrated in FIG. 3A. [Figure 3C] FIG. 3C is an enlarged, partially cut-away end view that generally illustrates a step in an exemplary method for producing a second mold according to an embodiment of the present disclosure, the step following the step illustrated in FIG. 3B. [Figure 3D] FIG. 3D is an enlarged, partially cut-away end view that generally illustrates a step in an exemplary method for producing a second mold according to an embodiment of the present disclosure, the step following the step illustrated in FIG. 3C. [Figure 4] FIG. 4 is a plan view that illustrates a schematic projection-recess pattern of a first mold according to an embodiment of the present disclosure. [Diagram 5] FIG. 5 is a plan view conceptually showing a positional deviation vector of the first mold in one embodiment of the present disclosure. [Figure 6] FIG. 6 is a graph showing a simulation result of the relationship between the degree difference and the maximum calculated value difference in the X direction when fitting with an approximate polynomial in one embodiment of the present disclosure. [Figure 7] FIG. 7 is a graph showing a simulation result of the relationship between the degree difference and the maximum calculated value difference in the Y direction when fitting with an approximate polynomial in one embodiment of the present disclosure. [Figure 8] FIG. 8 is a graph showing the results of a simulation of the relationship between values ​​obtained by uniformly adjusting coefficients in an embodiment of the present disclosure and the positional accuracy of a secondary mold produced using a primary mold. [Figure 9]FIG. 9 is a graph showing the results of a simulation of the relationship between the uniformly adjusted coefficients and the tertiary mold produced using the secondary mold in one embodiment of the present disclosure. [Figure 10] FIG. 10 is a block diagram illustrating a schematic configuration of one aspect of a drawing system according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In the drawings attached to this specification, the shape, scale, aspect ratio, etc. of each part may be changed or exaggerated from the actual one in order to facilitate understanding. In this specification, a numerical range expressed using "~" means a range including the numerical values ​​written before and after "~" as the lower limit and upper limit, respectively. In this specification, terms such as "film", "sheet", and "plate" are not distinguished from each other based on the difference in name. For example, "plate" is a concept that also includes members that can be generally called "sheet" and "film".

[0022] <Manufacturing method of imprint mold> FIG. 1 is a flow chart illustrating steps in a method for manufacturing an imprint mold according to one embodiment of the present disclosure.

[0023] In the method for manufacturing an imprint mold according to this embodiment, first, a first mold having a first concave-convex pattern is manufactured based on pattern data relating to the concave-convex pattern (S1). The imprint mold manufactured in this embodiment is used to manufacture a template having a transferred concave-convex pattern by transferring the concave-convex pattern through an imprint process using an imprint mold having a concave-convex pattern. Examples of shapes of the concave-convex pattern, the first concave-convex pattern, and the transferred concave-convex pattern include a pillar shape, a hole shape, a line-and-space shape, and the like.

[0024] The pattern data on the concave-convex pattern can be generated from the transferred concave-convex pattern data of the template having the transferred concave-convex pattern. Specifically, the pattern data can be generated by mirror-inverting the transferred concave-convex pattern data. The pattern data on the concave-convex pattern includes graphic information on the pattern-forming surface (surface on which the concave-convex pattern is formed) of the imprint mold (for example, coordinate data indicating the pattern-forming surface; coordinate data indicating the dimensions, shape (shape in plan view), arrangement (position of each concave-convex pattern on the pattern-forming surface), etc.), information on the concave-convex pattern (for example, information on whether the pattern is concave or convex, information on the height (or depth) of the convex (or concave) pattern, etc.), etc. The coordinate data indicating the pattern-forming surface, the concave-convex pattern, etc. can be, for example, coordinate values ​​with the geometric center of the pattern-forming surface of the imprint mold as the origin. The transfer pattern data also includes graphic information on the pattern forming surface of the template (the surface on which the transferred concave-convex pattern is formed) (for example, coordinate data indicating the pattern forming surface; coordinate data indicating the dimensions, shape (shape in plan view), arrangement (position of each transferred concave-convex pattern on the pattern forming surface), etc. of the transferred concave-convex pattern), information regarding the concaves and convexes of the transferred concave-convex pattern (for example, information on whether the pattern is concave or convex, information on the height (or depth) of the convex (or concave) pattern, etc.). Note that the coordinate data indicating the pattern forming surface, the transferred concave-convex pattern, etc. can be, for example, coordinate values ​​with the geometric center of the pattern forming surface of the template as the origin.

[0025] In this embodiment, the dimensions of the concave-convex pattern of the imprint mold (or the dimensions of the first concave-convex pattern of the first mold) and the dimensions of the transferred concave-convex pattern of the template (or the dimensions of the second concave-convex pattern of the second mold) are preferably about 100 nm or less, more preferably about 60 nm or less, and particularly preferably about 30 nm or less. In general, when a replica mold is produced through an imprint process based on a master mold, the amount of positional deviation in the replica mold (the distance between the position where the concave-convex pattern should be formed in the replica mold and the position where the concave-convex pattern is actually formed in the replica mold) is considered to be about 1 to 50 nm, although it depends on the replica mold production conditions (imprint conditions, etching conditions, the type of base material and imprint resin used, etc.). On the other hand, the allowable range of the amount of positional deviation of the concave-convex pattern in the replica mold is generally about 10% or less of the dimensions of the concave-convex pattern. Therefore, the method for producing an imprint mold according to this embodiment is particularly useful when producing a master mold used to produce a replica mold including a concave-convex pattern of about 100 nm or less by nanoimprint lithography. Note that the dimensions of the concave-convex pattern, the first concave-convex pattern, the second concave-convex pattern, and the transferred concave-convex pattern refer to, for example, the diameter in a plan view when the shape of each pattern is a pillar shape or a hole shape, and the short-side length of the convex portion or concave portion when the shape of each pattern is a line-and-space shape.

[0026] An example of a method for producing a first mold in this embodiment will now be described. Figures 2A to 2D are partially enlarged cross-sectional end views that outline each step of an example of a method for producing a first mold in this embodiment.

[0027] The method for producing the first mold in this embodiment is based on pattern data regarding the concave-convex pattern, and is produced, for example, by electron beam (EB) lithography, and includes a substrate preparation step, a resist film formation step, a resist pattern formation step, and a concave-convex pattern formation step.

[0028] In the substrate preparation step, a substrate 2 having a first surface 21 and a second surface 22 facing the first surface 21 is prepared (see FIG. 2A).

[0029] The substrate 2 is not particularly limited, and examples thereof include glass substrates such as quartz glass substrates, soda glass substrates, fluorite substrates, calcium fluoride substrates, magnesium fluoride substrates, non-alkali glass substrates such as barium borosilicate glass, amino borosilicate glass, and aluminosilicate glass, resin substrates such as polycarbonate substrates, polypropylene substrates, polyethylene substrates, polymethyl methacrylate substrates, and polyethylene terephthalate substrates, and transparent substrates such as laminated substrates formed by laminating two or more substrates arbitrarily selected from the above. In this embodiment, "transparent" means that the photocurable resin can be cured by light irradiated through the substrate 2, and for example, the transmittance of light having a wavelength of 300 to 450 nm is preferably 70% or more, and more preferably 90% or more.

[0030] The planar shape of the base material 2 is not particularly limited, and examples thereof include a substantially rectangular shape, a substantially square shape, etc. When the base material 2 is made of a quartz glass substrate, the planar shape of the base material 2 is usually a substantially rectangular shape.

[0031] The size of the base material 2 is not particularly limited, but when the base material 2 is made of the above-mentioned quartz glass substrate, the size of the base material 2 is, for example, about 152 mm × 152 mm. The thickness T1 of the base material 2 can be appropriately set, for example, in the range of about 300 μm to 10 mm, taking into consideration strength, handling suitability, and the like.

[0032] In the resist film forming step, a resist film 3 is formed on the first surface 21 of the substrate 2 (see FIG. 2B).

[0033] The resin material (resist material) constituting the resist film 3 is not particularly limited, and examples thereof include negative or positive type electron beam reactive resist materials generally used in electron beam lithography processing, etc., and preferably chemically amplified electron beam reactive resist materials. The resist material may be the same as the resist material used when manufacturing the target imprint mold.

[0034] The thickness of the resist film 3 is not particularly limited, but is preferably set to be substantially the same as the thickness of the resist film when the target imprint mold is manufactured. In a step described later (see FIG. 2C), a resist pattern 31 formed by patterning the resist film 3 is used as a mask when etching the substrate 2.

[0035] The method for forming the resist film 3 on the first surface 21 of the substrate 2 is not particularly limited, and may be any conventionally known method, such as applying a resist material onto the first surface 21 using a coating machine such as a spin coater or a spray coater, or laminating a dry film resist containing the above-mentioned resin component onto the first surface 21 and heating (pre-baking) at a predetermined temperature as desired.

[0036] In the resist pattern forming step, a resist pattern 31 having predetermined openings 32 is formed at desired positions on the first surface 21 of the substrate 2 (see FIG. 2C). The resist pattern 31 can be formed, for example, by electron beam lithography using an electron beam lithography apparatus. At this time, a pattern latent image is formed on the resist film 3 by the electron beam lithography apparatus using pattern data relating to the concave-convex pattern.

[0037] The shape and dimensions of openings 32 in resist pattern 31 can be set appropriately according to the shape and dimensions of recesses to be formed on first surface 21 of substrate 2 in the process of producing first mold 1 in this embodiment.

[0038] In the uneven pattern forming step, the first surface 21 side of the substrate 2 is etched using the resist pattern 31 formed as described above as a mask, thereby forming the recesses 4, and the first mold 1 can be produced (see FIG. 2D). In the present embodiment, the first surface 21 of the substrate 2 is etched using the resist pattern formed on the first surface 21 as a mask, but the present invention is not limited to such an embodiment. For example, a hard mask layer and a resist film 3 may be laminated in this order on the first surface 21 of the substrate 2 to form a resist pattern 31, the hard mask layer may be etched using the resist pattern 31 as a mask to form a hard mask pattern, and the first surface 21 of the substrate 2 may be etched using the hard mask pattern as a mask. The hard mask layer may be formed by a known film forming method such as sputtering, PVD, CVD, etc. using, for example, chromium-based materials such as chromium, chromium nitride, chromium oxide, and chromium oxynitride; tantalum-based materials such as tantalum, tantalum nitride, tantalum oxide, tantalum oxynitride, tantalum oxide boride, and tantalum oxynitride, etc., alone or in combination of two or more of them selected arbitrarily. The thickness of the hard mask layer can be appropriately set depending on the etching selectivity with respect to the material constituting the base material 2, the amount of etching (etching depth) in each lithography step, and the like.

[0039] The first concave-convex pattern of the first mold 1 manufactured as described above is substantially identical to the dimensions, shape, arrangement, etc. of the concave-convex pattern in the pattern data relating to the concave-convex pattern, but there is some positional deviation in the first concave-convex pattern. A correction value is obtained in a process described below from information relating to this positional deviation (positional deviation component). Note that the first mold 1 is preferably manufactured under the same manufacturing conditions as those used when manufacturing the target imprint mold (for example, the material of the base material constituting the imprint mold; when the imprint mold is manufactured by electron beam lithography, the electron beam sensitive resist material used, the electron beam irradiation conditions, etc.).

[0040] Next, a second mold having a second concave-convex pattern is produced through an imprint process using the first mold produced as described above (S2). The imprint process for producing the second mold can be carried out by a conventionally known method.

[0041] An example of a method for producing the second mold in this embodiment will now be described. Figures 3A to 3D are partially enlarged cross-sectional end views that outline each step of an example of a method for producing the second mold in this embodiment.

[0042] The method for producing a second mold in this embodiment is a method for using a first mold 1 to transfer the concave and convex pattern of the first mold 1 to an imprinting resin supplied on a transfer substrate 5, and includes a resin supplying step, a transfer step, a curing step, and a demolding step.

[0043] In the resin supplying step, for example, droplets 6 of the imprint resin are discretely discharged from an inkjet head (not shown) and supplied to a desired region on the transfer substrate 5 (see FIG. 3A).

[0044] Examples of the substrate 5 include glass substrates such as quartz glass substrates, soda glass substrates, fluorite substrates, calcium fluoride substrates, magnesium fluoride substrates, non-alkali glass substrates such as barium borosilicate glass, amino borosilicate glass, and aluminosilicate glass, resin substrates such as polycarbonate substrates, polypropylene substrates, polyethylene substrates, polymethyl methacrylate substrates, and polyethylene terephthalate substrates, the substrates at least partially doped with metal, transparent substrates such as laminated substrates formed by laminating two or more substrates arbitrarily selected from the above, semiconductor substrates such as silicon substrates, gallium arsenide substrates, and potassium nitride substrates, metal substrates, and composite substrates formed by any combination of materials constituting the substrates. The substrate 5 may also be a substrate on which a desired pattern structure such as fine wiring used in semiconductors and displays, a photonic crystal structure, an optical waveguide, or an optical structure such as holography is formed. In FIG. 3A, the substrate 5 having the convex structure 51 is shown as an example, but the substrate 5 may not have the convex structure 51.

[0045] The imprint resin may be appropriately selected as long as it has a fluidity that allows it to be discharged from an inkjet head. For example, the imprint resin contains a base agent, an initiator, and a crosslinking agent, and may contain a release agent for suppressing adhesion to the mold and an adhesive agent for improving adhesion to the transfer substrate 31 as necessary. The imprint resin to be used may be appropriately selected depending on the use, characteristics, physical properties, etc. of the pattern structure to be formed on the transfer substrate 5. For example, if the use of the pattern structure is for lithography (use as an etching mask for etching the transfer substrate 5), it is desirable to use an imprint resin that has high etching resistance, low viscosity, and can produce a pattern structure with a small residual film thickness. It is desirable for the imprint resin to have characteristics that satisfy compatibility with the inkjet head. Since the viscosity and surface tension of the liquid that is compatible with the inkjet head differ depending on the structure and material of the inkjet head, the characteristics of the imprint resin to be used may be appropriately adjusted depending on the structure and material of the inkjet head, or an inkjet head that is compatible with the characteristics of the imprint resin to be used may be used.

[0046] In addition, the number of droplets 6 of imprint resin discretely supplied onto the transfer substrate 5, the dropping positions of the droplets 6, etc. can be appropriately set depending on the dropping amount of the droplets 6, the total amount of imprint resin required, the thickness of the residual film of the pattern structure formed on the transfer substrate 5, etc.

[0047] In the above-mentioned resin supplying process, the method of supplying the imprinting resin onto the transfer substrate 5 is by inkjet, but this is not limited to this, and the imprinting resin may also be applied to the transfer substrate 5 by a spin coating method.

[0048] In the transfer step, the first mold 1 and the transfer substrate 5 are brought close to each other, and an imprint resin is spread between the first mold 1 and the transfer substrate 5 to form an imprint resin layer 61 (see FIG. 3B).

[0049] In the curing step, the imprinted resin layer 61 is irradiated with UV light 7 from the second surface 22 side of the base material 2 of the first mold 1 to cure the imprinted resin layer 61, thereby forming a transferred resin layer 62 to which the concavo-convex pattern of the first mold is transferred (see FIG. 3C). When the transferred substrate 5 is made of a material having optical transparency, the imprinted resin layer 61 may be irradiated with UV light 7 from the transferred substrate 5 side, or the imprinted resin layer 62 may be irradiated with UV light 7 from both the second surface 22 side of the base material 2 of the first mold 1 and the transferred substrate 5 side.

[0050] In the demolding step, the transferred resin layer 62 and the first mold 1 are separated to form a pattern structure 63 on the transferred substrate 5 (see FIG. 3D). The transferred substrate 5 is then etched using the pattern structure 63 as a mask to produce a second mold having a second concavo-convex pattern. The second mold is preferably manufactured under the same manufacturing conditions as those used to manufacture the target template (e.g., the material of the base material constituting the template, the resin material of the imprinting resin, etching conditions, etc.).

[0051] Next, from the pattern data relating to the concave-convex pattern and the first concave-convex pattern in the first mold produced as described above, a first positional deviation component and a first residual component of the first concave-convex pattern that is misaligned from the position where the concave-convex pattern is to be formed in the imprint mold are sequentially determined (S3).

[0052] As shown in FIG. 4, a first mold is produced by electron beam (EB) lithography or the like based on pattern data relating to the concave-convex pattern. However, due to various influences such as deformation of the substrate constituting the first mold and the degree of density of the concave-convex pattern, the position P of at least a part of the first concave-convex pattern on the pattern-forming surface 1 of the first mold may be shifted from the position where it should be formed (the position of the concave-convex pattern of the imprint mold) P'. Such position shifts include position shift components that can be corrected by a position correction mechanism included in the imprint apparatus and position shift components that cannot be corrected or are difficult to correct by a position correction mechanism included in the imprint apparatus. The position shift components that can be corrected by the position correction mechanism include linear position shift components such as a position shift component in which the outline shape of the area where the concave-convex pattern is formed is enlarged to the same size and a position shift component in which the outline shape of the approximately rectangular area is distorted to a parallelogram or trapezoid. On the other hand, the position shift components that cannot be corrected or are difficult to correct by the position correction mechanism include nonlinear position shift components. In this embodiment, the linear positional deviation component is called the first-order positional deviation component, and the nonlinear positional deviation component is called the residual component. In this embodiment, the position P' in the pattern data is compared with the position P of each first concave-convex pattern of the first mold 1, and a first positional deviation amount from the position P' in the pattern data to the position P of each first concave-convex pattern of the first mold 1 is obtained. Then, the first positional deviation component, which is the linear positional deviation component of the first concave-convex pattern, is obtained from the first positional deviation amount. The first residual component, which is the nonlinear positional deviation component of the first concave-convex pattern, is calculated by subtracting the first positional deviation component from the first positional deviation amount. As for the second concave-convex pattern of the second mold, the second positional deviation component, which is the linear positional deviation component, and the second residual component, which is the nonlinear positional deviation component, are obtained as described below, and the pattern data can be corrected from the difference between the first residual component and the second residual component.

[0053] Deformation of the mold or substrate during imprinting, which is one of the causes of misalignment of the concave-convex pattern, can occur, for example, when the mold or substrate is adsorbed to a holder that holds the mold or a stage that carries the substrate. However, examples of such deformation include deformation caused by adsorbing the mold or substrate to a holder that holds the mold or a stage that carries the substrate depending on the shape of the mold or substrate (the shape of the surface that contacts the stage, etc.), and deformation caused depending on the surface shape of the holder or stage of the imprinting apparatus. Of these, deformation caused depending on the surface shape of the holder or stage of the imprinting apparatus is specific to the imprinting apparatus and may be reproducible. Therefore, it is considered possible to improve the positional accuracy by predicting the amount of misalignment due to this deformation and correcting it.

[0054] In order to extract the amount of misalignment due to deformation that occurs depending on the surface shape of the holder or stage of the imprinting apparatus, it is important to suppress the misalignment due to uncertain factors such as misalignment due to stress generated in the resin for imprinting. By suppressing the misalignment due to such uncertain factors, most of the misalignment components of the concave-convex pattern can be made to consist of misalignment components due to deformation that occurs linearly depending on the shape of the mold or substrate and misalignment components due to deformation that depends on the surface shape of the holder or stage of the imprinting apparatus. The misalignment components due to deformation that occurs linearly depending on the shape of the mold or substrate can be extracted from the misalignment components of the entire fine concave-convex pattern, and are deformations that differ depending on the mold or substrate used in the imprinting process, and only the amount of misalignment due to deformation that depends on the shape of the mold or substrate can be extracted from the distribution of misalignment of the entire fine concave-convex pattern. Therefore, it is necessary to obtain the amount of misalignment due to deformation that depends on the shape of the mold and substrate, subtract the amount of misalignment due to deformation that depends on the shape of the mold or substrate from the distribution of misalignment of the entire concave-convex pattern, and obtain the residual component, thereby separating the amount of misalignment due to deformation that depends on the shape of the mold or substrate from the amount of misalignment of the entire fine concave-convex pattern. As described above, among the deformations that depend on the mold or the substrate, the positional deviation component that causes the contour shape of the region where the concave-convex pattern is formed to expand at the same magnification, and the positional deviation component that distorts the contour shape of the region from a substantially rectangular shape to a parallelogram or trapezoid can be corrected by using a pattern correction mechanism in the imprint apparatus, so that it is considered that the positional accuracy can be improved without separating it from the positional deviation amount of the entire concave-convex pattern. Therefore, it is considered that the imprint mold can be manufactured with extremely high positional accuracy by extracting the positional deviation due to the deformation that occurs depending on the surface shape of the holder or the stage, which is specific to the imprint apparatus, and reflecting the positional deviation in the pattern data. Based on this idea, in the manufacturing method of the imprint mold according to this embodiment, the pattern data is corrected using the residual component obtained by subtracting the positional deviation amount due to the deformation that depends on the shape of the mold or the substrate, as described later.

[0055] The method for calculating the first positional deviation component and the first residual component included in the positional deviation amount of the first uneven pattern in which a positional deviation has occurred is not particularly limited, but may be, for example, a method using the least squares method. Specifically, they can be calculated by the method described in detail below.

[0056] A plurality of reference marks are formed on the pattern-formed surface of the first mold at approximately equal intervals in both the vertical and horizontal directions in addition to the concave-convex pattern, and the position data (coordinate data) of the reference marks M1 to M4 formed on the pattern-formed surface 1 of the first mold is measured using a position measuring device (e.g., Mask Registration Metrology System IPRO Series, manufactured by KLA-Tencor) (see FIG. 5). The dimensions and shapes of the reference marks can be appropriately set according to the position measuring device used. In this embodiment, the correction amount is obtained from the position data (coordinate data) of each of the four reference marks M1 to M4, but this is not limited to this method, and five or more reference marks may be set. The more the number of reference marks, the more detailed the position deviation component can be analyzed.

[0057] The first misalignment amount can be obtained by comparing the obtained position data (coordinate data) of each of the fiducial marks M1-M4 with the position data of each of the fiducial marks M1-M4 in the pattern data (coordinate data of the designed positions M1'-M4' where each of the fiducial marks M1-M4 is to be formed in the first mold). As described above, the first misalignment amount includes a first misalignment component which is a linear misalignment component that can be corrected by the position correction mechanism, such as a misalignment component in which the outer shape of the region where the concave-convex pattern is formed is enlarged to the same size, and a misalignment component in which the outer shape of the approximately rectangular region is distorted to a parallelogram or trapezoid, and a first residual component which is a nonlinear misalignment component that cannot be or is difficult to correct by the position correction mechanism.

[0058] The method for calculating the first positional deviation component from the first positional deviation amount is not particularly limited, but for example, an EGA (Enhanced Global Alignment) method can be used. By using this method, the first positional deviation component can be obtained using the following formula (1).

[0059]

number

[0060] In the above formula (1), "dx" is the amount of misalignment in one direction (X direction) from the design positions M1' to M4' of the pattern-formed surface, "dy" is the amount of misalignment in the direction perpendicular to the X direction (Y direction) from the design positions M1' to M4' of the pattern-formed surface, "X" is the X-direction coordinate of the design positions M1' to M4' of each fiducial mark in a coordinate system with the center of the pattern-formed surface as the origin, and "Y" is the Y-direction coordinate of the design positions M1' to M4' of each fiducial mark in a coordinate system with the center of the pattern-formed surface as the origin. The above formula (1) is a polynomial for the design position coordinates X and Y in the coordinate system with the center of the pattern-formed surface as the origin, and is a model formula showing the relationship between the position coordinates X and Y and the misalignment amounts dx and dy. By using this model formula, the correction amount of the position coordinates of the pattern-formed surface can be obtained from the result of the misalignment amount.

[0061] In order to calculate the above correction amount using the above formula (1), the coefficient (a 0 ,a 1 b 0 ,b 1 This coefficient can be calculated by a statistical calculation such as the least squares method, for example, the least squares method using a matrix. For example, the coefficient a 0 is a coefficient corresponding to the positional deviation component due to the translation of the concave-convex pattern in the X direction, and the coefficient a 1 is a coefficient corresponding to the positional deviation component in the X direction when the contour shape of the pattern formation surface is enlarged to the same size, and the coefficient a 2is a coefficient corresponding to the positional deviation component in the X direction when the contour shape of the approximately rectangular pattern formation surface is distorted into a parallelogram shape, and coefficient b 0 is a coefficient corresponding to the positional deviation component due to the translation of the concave-convex pattern in the Y direction, and coefficient b 1 is a coefficient corresponding to the positional deviation component in the Y direction when the contour shape of the pattern formation surface is enlarged to the same size, and coefficient b 2 is a coefficient corresponding to a positional deviation component in the Y direction when the contour of a substantially rectangular pattern formation surface is distorted into a parallelogram.

[0062] When calculating the correction amount using the above formula (1), there is no particular limit to the order or the terms to be selected in the above formula (1). For example, the first positional deviation component can be calculated by using a linear formula (including linear terms), but the first positional deviation component may also be calculated by a quadratic formula (including linear and quadratic terms). For example, the coefficient a corresponding to the positional deviation component in the X direction when the contour shape of the substantially rectangular pattern formation surface is distorted into a trapezoid shape may be calculated by using the following formula: 3 and a coefficient b corresponding to the positional deviation component in the Y direction when the contour shape of the approximately rectangular pattern formation surface is distorted into a trapezoid. 3 The first misalignment amount may be calculated using an equation including a second-order term having the following formula: When calculating the misalignment component using the above formula (1), if an equation including third-order or higher terms (higher-order terms) is used, the difference (residual component) between the actual measurement value of the misalignment amount and the misalignment amount calculated by the least squares method becomes small. In other words, if the misalignment component is calculated using an equation not including higher-order terms, the residual component includes a higher-order misalignment component, that is, a nonlinear misalignment component of the concave-convex pattern that cannot be corrected or is difficult to correct by the position correction mechanism of the imprinting apparatus. Therefore, by using the above formula (1) including first-order and second-order terms, it is possible to calculate the first misalignment component, which is a linear misalignment component of the concave-convex pattern that can be corrected by the position correction mechanism of the imprinting apparatus.

[0063] A first residual component is calculated, which is the difference between the actually measured positional deviation amount at each coordinate and the first positional deviation component calculated using the above formula (1). As will be described later, in this embodiment, this first residual component is used when correcting the pattern data.

[0064] Next, a second positional deviation component and a second residual component of the second concave-convex pattern, which is misaligned from the position where the transferred concave-convex pattern of the template should be formed, are determined from the transferred concave-convex pattern data relating to the transferred concave-convex pattern and the second concave-convex pattern of the second mold produced as described above (S4).

[0065] A second mold having a second concave-convex pattern is produced through an imprinting process using a first mold. Various influences can be considered, such as deformation of the substrate constituting the first mold and / or second mold during the imprinting process, the degree of density of the concave-convex pattern in the first mold, stress generated in the imprinting resin when the first mold is peeled off, and deformation that occurs depending on the shape of the mold holder or stage of the imprinting apparatus. In particular, deformation that occurs depending on the shape of the mold holder or stage of the imprinting apparatus can cause the position of at least a part of the concave-convex pattern on the pattern forming surface of the second mold to shift from the position where it is originally supposed to be formed (the designed position of the transferred concave-convex pattern).

[0066] In this way, the template having the transferred concave-convex pattern needs to be created based on the transferred concave-convex pattern data in which the arrangement of the transferred concave-convex pattern is corrected, taking into account the second positional deviation component of the second concave-convex pattern. For this reason, it is necessary to obtain the second positional deviation component and the second residual component in the same manner as in the step (S3) of obtaining the first positional deviation component and the first residual component. Note that the method of obtaining the second positional deviation component is not particularly limited, but for example, the second positional deviation component may be obtained using the EGA (Enhanced Global Alignment) method in the same manner as the calculation of the first positional deviation component described above, and the second residual component may be calculated by subtracting the second positional deviation component from the actually measured positional deviation amount.

[0067] Next, a correction value for correcting the pattern data is obtained from the difference between the first residual component and the second residual component (S5). As described above, the first residual component and the second residual component contain a nonlinear positional deviation component of the concave-convex pattern. Therefore, by obtaining a correction value from the difference between the first residual component and the second residual component and reflecting the correction value in the pattern data, it is possible to prevent the occurrence of a positional deviation that cannot be corrected or is difficult to correct by the pattern position correction mechanism of the imprinting apparatus, and therefore it is possible to manufacture an imprint mold that can manufacture a template having a desired transfer concave-convex pattern with high accuracy.

[0068] As a method for obtaining the correction value, for example, the difference between the first residual component and the second residual component is expressed by an approximate polynomial including quadratic or higher terms of the above formula (1), and the coefficients of the terms are obtained by the least squares method. By calculating the coefficients of each term using this method, the third positional deviation component dependent on the function system of each term can be obtained. By using the calculated third positional deviation component as a coefficient and substituting the measured values ​​of each coordinate into the quadratic or higher approximate polynomial used when expressing the difference between the first residual component and the second residual component again, the correction amount of the first uneven pattern displaced from the uneven pattern at each coordinate can be obtained. Note that the correction value may be obtained by substituting the value obtained by inverting the sign of the coefficient of the calculated third positional deviation component into the quadratic or higher approximate polynomial used when expressing the difference between the first residual component and the second residual component again.

[0069] As described above, in an approximate polynomial including quadratic or higher terms, the difference between the value calculated using the approximate polynomial and the actually measured positional deviation amount becomes smaller as the number of terms increases, but a correction value can be obtained using an approximate polynomial including a cubic term. FIG. 6 is a graph showing a simulation result of the relationship between the degree difference and the maximum calculated value difference in the X direction when fitting with an approximate polynomial in one embodiment of the present disclosure, and FIG. 7 is a graph showing a simulation result of the relationship between the degree difference and the maximum calculated value difference in the Y direction when fitting with an approximate polynomial in one embodiment of the present disclosure. As shown in FIGS. 6 and 7, the difference in the maximum calculated value between the quadratic expression and the cubic expression is 0.4 nm or more, while the difference in the maximum calculated value between the cubic expression and the quartic expression is about 0.2 nm at most. Therefore, when obtaining a correction value, it is sufficient to calculate using an approximate polynomial including a coefficient of a cubic term, and the coefficients of the quartic and higher terms may be omitted.

[0070] Next, the pattern data is corrected based on the correction value obtained as described above to generate corrected pattern data (S6). In this case, the corrected pattern data may be generated by correcting the pattern data based on a value obtained by reducing the correction value at a predetermined magnification. FIG. 8 is a graph showing a simulation result of a relationship between a value obtained by uniformly adjusting the coefficient in an embodiment of the present disclosure and the position accuracy of an imprint mold (hereinafter, sometimes referred to as a "secondary mold") produced using an imprint mold (hereinafter, sometimes referred to as a "primary mold") produced based on the adjustment. FIG. 9 is a graph showing a simulation result of a relationship between a value obtained by uniformly adjusting the coefficient in an embodiment of the present disclosure and the position accuracy of an imprint mold (hereinafter, sometimes referred to as a "tertiary mold") produced using the secondary mold. As is clear from the results shown in FIGS. 8 and 9, the position accuracy is improved when the tertiary mold is produced using the secondary mold compared to when the pattern data is corrected based on a value obtained by uniformly reducing the correction value at a predetermined magnification (reduced correction value), a primary mold is produced from the corrected pattern data, and a secondary mold is produced using the primary mold. Even when the pattern data is corrected based on the reduction correction value, the position accuracy is improved compared to when the pattern data is not corrected. In addition, the difference (absolute value) between the position accuracy when the pattern data is corrected based on the correction value and the position accuracy when the pattern data is corrected based on the reduction correction value is smaller when the tertiary mold is produced using the secondary mold than when the secondary mold is produced using the primary mold. Therefore, depending on the position accuracy required for the primary mold to be produced, the secondary mold produced from the primary mold, and the tertiary mold produced from the secondary mold, the pattern data may be corrected based on the reduction correction value. Note that, although an example has been described in which the coefficients of each term of second or higher degree are reduced by a uniform factor, the reduction factor of each coefficient of each term of second or higher degree may be different, for example, by reducing only the coefficient of the second order term of each term of the approximate polynomial.

[0071] Finally, based on the generated corrected pattern data, an imprint mold having a concave-convex pattern is fabricated by electron beam lithography or the like (S7). The imprint mold is manufactured under the same manufacturing conditions as those in the process of fabricating the first mold described above.

[0072] After the step (S7) of preparing the imprint mold, the obtained imprint mold may be used to prepare a template having a transferred concave-convex pattern by transferring the concave-convex pattern through an imprint process, and the arrangement of the transferred concave-convex pattern on the template may be compared with the arrangement of the transferred concave-convex pattern in the transferred concave-convex pattern data. If there is any positional deviation in the transferred concave-convex pattern on the template, the corrected pattern data may be further corrected based on the positional deviation component of the transferred concave-convex pattern before the imprint mold is manufactured.

[0073] When the correction pattern data is generated as described above and an imprint mold is manufactured based on the correction pattern data, the arrangement of at least a part of the concave-convex pattern in the obtained imprint mold will be different from the arrangement of the corresponding transferred concave-convex pattern in the transferred concave-convex pattern data. However, the correction pattern data is generated taking into consideration the positional deviation component caused by the imprint process in the template manufacturing process, and the imprint mold is manufactured based on the correction pattern data. Therefore, if a template is manufactured through the imprint process using the imprint mold, a template having a transferred concave-convex pattern can be manufactured with high accuracy without causing a positional deviation of the transferred concave-convex pattern. Therefore, according to this embodiment, an imprint mold used to manufacture a template having a transferred concave-convex pattern can be manufactured with high accuracy.

[0074] In the method for manufacturing an imprint mold according to this embodiment, a plurality of second molds may be fabricated through an imprint process using a first mold. In this case, the second positional deviation component and the second residual component may be calculated sequentially for each of the second molds, and a correction value may be calculated from an average value of the differences between the first residual component and the second residual components of each of the plurality of second molds.

[0075] In the method of manufacturing an imprint mold according to this embodiment, a plurality of first molds may be manufactured based on pattern data, and a plurality of second molds may be manufactured through an imprint process using each of the plurality of first molds. In this case, a first positional deviation component and a first residual component are sequentially obtained for each of the plurality of first molds, and a second positional deviation component and a second residual component are sequentially obtained for each of the plurality of second molds. Then, a correction value can be obtained from the difference between the average value of the first residual components of each of the plurality of first molds and the average value of the second residual components of each of the plurality of second molds.

[0076] In this embodiment, as long as the imprinting apparatus for performing the imprinting process is the same, the correction value obtained as described above can be used to correct the pattern data, regardless of the type of the concave-convex pattern of the imprint mold to be manufactured. Since the correction value is a correction value for correcting the positional deviation caused by the imprinting apparatus, regardless of the type of the concave-convex pattern, it can be used to correct the pattern data of the concave-convex pattern of the imprint mold as long as the imprinting apparatus used, particularly the mold holder and stage, are the same. This makes it possible to manufacture imprint molds with different types of concave-convex pattern dimensions, shapes, arrangements, etc. with high precision.

[0077] <Template manufacturing method> By using the imprint mold produced as described above, a template having a transferred concave-convex pattern by transferring the concave-convex pattern of the imprint mold can be produced. The template manufacturing method in this embodiment includes a template substrate preparation process for preparing a template substrate having a first surface and a second surface opposite to the first surface, an imprinting process for supplying an imprint resin onto the first surface of the template substrate and pressing the concave-convex pattern of the imprint mold against the imprint resin to form a transfer pattern, and an etching process for etching the template substrate using the transfer pattern as a mask.

[0078] Examples of the template substrate include glass substrates such as quartz glass substrates, soda glass substrates, fluorite substrates, calcium fluoride substrates, magnesium fluoride substrates, non-alkali glass substrates such as barium borosilicate glass, amino borosilicate glass, and aluminosilicate glass, resin substrates such as polycarbonate substrates, polypropylene substrates, polyethylene substrates, polymethyl methacrylate substrates, and polyethylene terephthalate substrates, the above substrates at least partially doped with metal, transparent substrates such as laminated substrates formed by laminating two or more substrates arbitrarily selected from the above, semiconductor substrates such as silicon substrates, gallium arsenide substrates, and potassium nitride substrates, metal substrates, and composite material substrates formed by any combination of materials constituting the above substrates. The transfer substrate 5 may be a substrate on which a desired pattern structure such as fine wiring used in semiconductors and displays, a photonics crystal structure, an optical waveguide, or an optical structure such as holography is formed. The template substrate may have a convex structure portion or may not have a convex structure portion.

[0079] The imprint resin may be appropriately selected as long as it has a fluidity that allows it to be discharged from an inkjet head. For example, the imprint resin contains a base agent, an initiator, and a crosslinking agent, and may contain a release agent that suppresses adhesion to the imprint mold and an adhesive agent for improving adhesion to the template substrate as necessary. The imprint resin to be used may be appropriately selected depending on the application, characteristics, physical properties, etc. of the pattern structure to be formed on the template substrate. For example, if the application of the pattern structure is for lithography (application as an etching mask for etching the template substrate), it is desirable to use an imprint resin that has high etching resistance, low viscosity, and can produce a pattern structure with a small residual film thickness. It is desirable for the imprint resin to have characteristics that satisfy compatibility with the inkjet head. Since the viscosity and surface tension of the liquid that is compatible with the inkjet head differ depending on the structure and material of the inkjet head, the characteristics of the imprint resin to be used may be appropriately adjusted depending on the structure and material of the inkjet head, or an inkjet head that is compatible with the characteristics of the imprint resin to be used may be used.

[0080] In addition, the imprint resin may be supplied discretely onto the template substrate. In this case, the number of droplets of the imprint resin, the droplet dropping positions, etc. can be appropriately set depending on the amount of droplets dropped, the total amount of imprint resin required, the thickness of the residual film of the pattern structure formed on the template substrate, etc.

[0081] The method for supplying the imprint resin onto the template base material is not limited to the inkjet method, and any other known coating method such as spin coating may be used.

[0082] In the imprinting process, the imprint mold and the template substrate are brought close to each other, and an imprint resin is spread between the imprint mold and the template substrate to form an imprint resin layer, and the imprint resin layer is cured to form a transfer resin layer to which the concave-convex pattern of the imprint mold is transferred. The transfer resin layer and the imprint mold are separated to form a pattern structure on the template substrate. In this imprinting process, by using the imprinting device used in producing the second mold, it is possible to produce a template having a highly accurate transfer concave-convex pattern. Finally, the template substrate is etched using the pattern structure as a mask to produce a template having a transfer concave-convex pattern.

[0083] The above-described method for manufacturing an imprint mold can be implemented in a drawing system 10 (see FIG. 10) used for manufacturing an imprint mold having a concave-convex pattern, which is used to create a template having a transferred concave-convex pattern to which a concave-convex pattern has been transferred.

[0084] <Drawing system> FIG. 10 is a block diagram illustrating a schematic configuration of one aspect of a drawing system according to an embodiment of the present disclosure. The drawing system 10 according to this embodiment includes a drawing device 11 that forms a pattern latent image on a mold substrate for manufacturing an imprint mold, and a pattern data correction device 12 that generates corrected pattern data used to form the pattern latent image by correcting pattern data related to a concave-convex pattern.

[0085] The pattern data correcting device 12 includes a positional deviation component generating section 13 , a correction value generating section 14 , and a corrected pattern data generating section 15 . The positional deviation component generating unit 13 can, for example, sequentially obtain a first positional deviation component and a first residual component of the first concave-convex pattern, which are caused by deviation from the position where the concave-convex pattern is to be formed in the imprint mold, from the positional data of the first concave-convex pattern of the first mold produced based on the pattern data and the pattern data, and sequentially obtain a second positional deviation component and a second residual component of the second concave-convex pattern, which are caused by deviation from the position where the transferred concave-convex pattern is to be formed in the template, from the positional data of the second concave-convex pattern of the second mold produced through the imprint process using the first mold and the transferred concave-convex pattern data. Note that various data such as the pattern data and the transferred pattern data may be stored in a data storage unit (not shown) of the pattern data correcting device 12.

[0086] The correction value generation unit 14 calculates a correction value for correcting the pattern data from the difference between the second or higher order misalignment component included in the first misalignment component and the second or higher order misalignment component included in the second misalignment component, from the first misalignment component and the second misalignment component calculated by the misalignment component generation unit 13. In this way, a correction value is calculated from the difference between the first residual component and the second residual component in each of the first mold and the second mold, and the correction value is reflected in the pattern data, thereby making it possible to manufacture an imprint mold capable of manufacturing a template having a desired transferred concavo-convex pattern.

[0087] The corrected pattern data generating unit 15 generates the corrected pattern data based on the correction value generated by the correction value generating unit 14. The corrected pattern data may be generated by correcting the pattern data based on a value obtained by reducing the correction value. For example, the coefficients of the quadratic or higher degree terms of the first approximation polynomial and the coefficients of the quadratic or higher degree terms of the second approximation polynomial may be multiplied by 0.8 to obtain the correction value.

[0088] Based on the corrected pattern data generated by the corrected pattern data generating unit 15, the drawing device 11 can form a pattern latent image on the resist film on the mold substrate. Note that the drawing device 11 in this embodiment is not particularly limited as long as it can form a pattern latent image on the resist film on the mold substrate based on the corrected pattern data. For example, based on the corrected pattern data, each pattern latent image may be formed using an electron beam drawing device, or each pattern latent image may be formed using a laser drawing device.

[0089] According to the drawing system 10 of the present embodiment, it is possible to form with high accuracy a latent pattern image of an imprint mold capable of manufacturing a template having a desired transfer concavo-convex pattern.

[0090] The above-described embodiments are described for the purpose of facilitating understanding of the present disclosure, and are not described for the purpose of limiting the present disclosure. Therefore, each element disclosed in the above embodiment is intended to include all design modifications and equivalents that fall within the technical scope of the present disclosure. EXAMPLES

[0091] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples in any way.

[0092] A quartz glass substrate (152 mm × 152 mm × 6.35 mm) was prepared, and a first mold 1 having the configuration shown in Fig. 2D was produced using an electron beam lithography device based on pattern data, and a quartz glass substrate (152 mm × 152 mm × 6.35 mm) was also prepared as a transfer substrate 5. Note that the pattern data was such that position accuracy measurement marks (reference marks) having a cross shape in plan view with a dimension of 1 µm were arranged in parallel in the X and Y directions at a pitch of 2 mm in a pattern area set on the first surface 21 of the first mold 1.

[0093] The first mold 1 was held by the mold holder of the imprinting device, and the transferee substrate 5 was held by the stage. An imprint resin was supplied onto the convex structure portion 51 of the transferee substrate 5, and the concave-convex pattern and the positional accuracy measurement mark (reference mark) of the first mold 1 were transferred to form a pattern structure 63 and a positional accuracy measurement mark on the convex structure portion 51 of the transferee substrate 5.

[0094] The position coordinates of the position accuracy measurement marks (reference marks) of first mold 1 and the position coordinates of the position accuracy measurement marks transferred onto convex structure portion 51 of transferee substrate 5 were measured using a coordinate measuring device (IPRO Series, manufactured by KLA-Tencor Corporation). As a result, the position accuracy (3σ) of the position accuracy measurement marks (reference marks) of first mold 1 was 1.19 nm in the X direction and 0.97 nm in the Y direction, and the position accuracy (3σ) of the position accuracy measurement marks of transferee substrate 5 was 1.45 nm in the X direction and 1.11 nm in the Y direction.

[0095] Next, the first positional deviation component, the first residual component, the second positional deviation component, and the second residual component were calculated using the above formula (1) including the first-order term. From the difference between the first residual component and the second residual component, the correction value was calculated using the above formula (1) including the second-order term and the third-order term. Note that a plurality of first molds 1 and transfer substrates 5 were prepared, and the correction value was calculated in the same manner as the above method. The average value of the correction values ​​was calculated from the obtained plurality of correction values. The pattern data was corrected using the average value of the correction values ​​to generate corrected pattern data. Based on the corrected pattern data, an imprint mold was produced by the electron beam lithography apparatus used when the first mold 1 was produced. Then, the imprint mold was held by the mold holder of the imprint apparatus used when the pattern structure 63 was formed, and the transfer substrate 5 was held on the stage, and a pattern structure was formed in the same manner as above.

[0096] The position coordinates of the position accuracy measurement mark of the imprint mold and the position coordinates of the position accuracy measurement mark on the convex structure portion 51 of the transfer substrate 5 were measured using a coordinate measuring device (IPRO Series, manufactured by KLA Tencor Corporation). As a result, the position accuracy (3σ) of the position accuracy measurement mark of the imprint mold was 1.44 nm in the X direction and 0.92 nm in the Y direction, and the position accuracy (3σ) of the position accuracy measurement mark of the transfer substrate 5 was 1.25 nm in the X direction and 0.80 nm in the Y direction. From this result, it was confirmed that the position deviation due to the deformation caused depending on the surface shape of the holder and the stage, which is specific to the imprint device, can be suppressed, and the desired transfer concave-convex pattern can be manufactured on the transfer substrate 5 with high accuracy. Note that in this embodiment, regardless of the presence or absence of a concave-convex pattern that can be formed in the pattern area set on the first surface 21 of the first mold 1, the position deviation of the position accuracy measurement mark of the transfer substrate 5 can be suppressed.

Claims

1. A method for manufacturing an imprint mold having a concave-convex pattern, comprising the steps of: the imprint mold is used for producing a template having a transferred concave-convex pattern by transferring the concave-convex pattern; The manufacturing method includes: producing a first mold having a first concave-convex pattern based on design pattern data relating to a design of the concave-convex pattern; preparing a second mold having a second concave-convex pattern through an imprint process using the first mold; determining a first positional deviation amount of the first concave-convex pattern, which is deviated from a position where the concave-convex pattern is to be formed in the imprint mold, from the design pattern data and first measured pattern data obtained by actually measuring the first concave-convex pattern; determining a first positional deviation component, which is a linear positional deviation component of the first concave-convex pattern, from the first positional deviation amount by a least squares method using a polynomial that represents the first positional deviation amount; determining a first residual component, which is a nonlinear misalignment component of the first uneven pattern from the first misalignment amount and the first misalignment component, and is a difference between the first misalignment amount and the first misalignment component; determining a second positional deviation amount of the second concave-convex pattern, which is deviated from a position where the transferred concave-convex pattern of the template is to be formed, from design transferred concave-convex pattern data relating to a design of the transferred concave-convex pattern and second measured pattern data obtained by actually measuring the second concave-convex pattern; determining a second positional deviation component, which is a linear positional deviation component of the second concave-convex pattern, from the second positional deviation amount by a least squares method using a polynomial that represents the second positional deviation amount; determining a second residual component, which is a nonlinear misalignment component of the second uneven pattern from the second misalignment amount and the second misalignment component, and is a difference between the second misalignment amount and the second misalignment component; determining a correction value for correcting the pattern data from a difference between the first residual component and the second residual component; generating corrected pattern data by correcting the pattern data based on the correction value; producing the imprint mold having the concave-convex pattern based on the corrected pattern data; A method for manufacturing an imprint mold comprising:

2. 2. The method for manufacturing an imprint mold according to claim 1, wherein, in the step of calculating the correction value, a third positional deviation component corresponding to the correction value is calculated using an approximate polynomial that represents a difference between the first residual component and the second residual component, and the correction value is calculated based on the third positional deviation component.

3. The method for manufacturing an imprint mold according to claim 2 , wherein the correction value is a value calculated from the approximation polynomial using a value obtained by inverting the sign of the third positional deviation component.

4. The method for manufacturing an imprint mold according to claim 2 or 3, wherein the approximation polynomial is made up of quadratic terms and cubic terms.

5. A step of obtaining a reduced correction value by uniformly reducing the correction value by a predetermined magnification, The method for manufacturing an imprint mold according to any one of claims 1 to 4, wherein the corrected pattern data is generated by correcting the pattern data based on the reduction correction value.

6. Producing a plurality of the second molds through an imprint process using the first mold; determining the second positional deviation component and the second residual component for each of the second molds; The method for manufacturing an imprint mold according to any one of claims 1 to 5, wherein the correction value is determined from a difference between the first residual component and an average value of a plurality of the second residual components.

7. A plurality of the first molds are fabricated based on the pattern data; producing a plurality of the second molds through an imprint process using each of the plurality of first molds; determining the first positional deviation component and the first residual component for each of the plurality of first molds; determining the second positional deviation component and the second residual component for each of the second molds; The method for manufacturing an imprint mold according to any one of claims 1 to 6, wherein the correction value is determined from a difference between an average value of a plurality of the first residual components and an average value of a plurality of the second residual components.

8. A method for manufacturing an imprint mold according to any one of claims 1 to 7, wherein the imprint mold is used to produce the template using an imprint apparatus used in the imprint process in the step of producing the second mold.

9. A method of manufacturing the template using the imprint mold of claim 8, comprising the steps of: a template substrate preparation step of preparing a template substrate having a first surface and a second surface opposite to the first surface; an imprinting step of supplying an imprint resin onto the first surface of the template base material and pressing the concave-convex pattern of the imprint mold against the imprint resin to form a transfer pattern; an etching step of etching the template substrate using the transfer pattern as a mask; Including, A method for manufacturing a template in which the transfer pattern is formed using the imprint apparatus in the imprint process.

10. A method for manufacturing an imprint mold having a different type of uneven structure from the uneven pattern of the imprint mold according to claim 8, comprising the steps of: the imprint mold is used for producing a template having a transferred concave-convex structure by transferring the concave-convex structure; correcting design data relating to the concave-convex structure based on the correction value to generate corrected design data; producing the imprint mold having the relief structure based on the corrected design data; Including, A method for manufacturing an imprint mold, wherein the imprint mold having the unevenness structure is used to produce the template having the transferred unevenness structure using an imprint apparatus used in the imprint process in the step of producing the second mold.

11. A drawing system used for producing an imprint mold having a concave-convex pattern by transferring a concave-convex pattern, the drawing system comprising: a drawing device for forming a pattern latent image on a mold substrate for manufacturing the imprint mold; a pattern data correction device that generates corrected pattern data used to form the pattern latent image by correcting design pattern data related to the design of the concave-convex pattern; Equipped with The pattern data correction device includes: A first positional deviation amount of the first concave-convex pattern, which is a deviation from a position where the concave-convex pattern is to be formed in the imprint mold, is obtained from first actual measurement pattern data obtained by actually measuring a first concave-convex pattern of a first mold produced based on the design pattern data and the design pattern data, a first positional deviation component which is a linear positional deviation component is obtained by a least squares method using a polynomial which indicates the first positional deviation amount, a difference between the first positional deviation amount and the first positional deviation component is obtained as a first residual component which is a non-linear positional deviation component, and a displacement component generating unit which calculates a second positional deviation amount of the second uneven pattern caused by displacement from a position where the transferred uneven pattern is to be formed in the template, based on second actual measurement pattern data obtained by actually measuring a second uneven pattern of a second mold produced through a printing process and design transfer pattern data related to a design of the transferred uneven pattern, calculates the second positional deviation component, which is a linear positional deviation component, by a least squares method using a polynomial indicating the second positional deviation amount, and calculates a difference between the second positional deviation amount and the second positional deviation component as a second residual component, which is a nonlinear positional deviation component; a correction value generating unit that obtains a correction value for correcting the pattern data from a difference between the first residual component and the second residual component; a correction pattern data generating unit that generates the correction pattern data based on the correction value; having The drawing apparatus is a drawing system that forms the pattern latent image on the mold substrate based on the corrected pattern data.

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