Imprint mold and method for manufacturing the same

Abstract

To provide an imprint mold and a method for manufacturing the imprint mold that can suppress deformation of an uneven pattern part of the imprint mold due to penetration of components such as water and oil contained in an imprint resin into a resin part of the imprint mold.SOLUTION: An imprint mold 10 includes an uneven pattern part 10P. The uneven pattern part 10P includes a resin part 20 having an uneven pattern shape, and a barrier layer 30 formed on the resin part 20. The barrier layer 30 has a shape that follows the uneven pattern shape of the resin part 20. The barrier layer 30 contains nickel or aluminum oxide.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to imprint molds and methods for manufacturing imprint molds. [Background technology]

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

[0003] In the imprinting method, a resin mold made of a resin material may be used. For example, a resin mold serving as a master mold on which a fine pattern is formed is manufactured by performing exposure and development processing on a photoresist film. For example, a master mold made of any material is used as a master plate, and the fine pattern of the master mold is transferred to a resin material by the imprinting method, thereby manufacturing a resin mold serving as a replica mold. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-194142 Summary of the Invention [Problem to be solved by the invention]

[0005] In the imprinting method, when a fine pattern of a resin mold is transferred to an imprint resin as a workpiece, aqueous or oily components such as a solvent contained in the imprint resin may permeate into the resin mold. In this case, the shape of the fine pattern of the resin mold changes due to the permeation of components such as the solvent contained in the imprint resin, making it difficult to transfer the desired fine pattern. [Means for solving the problem]

[0006] An imprint mold for solving the above problem is an imprint mold having a concave-convex pattern portion, the concave-convex pattern portion having a resin portion having a concave-convex pattern shape, and a barrier layer formed on the resin portion and having a shape that follows the concave-convex pattern shape, and the barrier layer contains nickel or aluminum oxide.

[0007] A method for manufacturing an imprint mold that solves the above-mentioned problems includes the steps of: pressing an imprint resin against a master mold having a first concave-convex pattern shape to form a second concave-convex pattern shape in the imprint resin by transferring the first concave-convex pattern shape to the imprint resin; and forming a barrier layer having a shape that follows the second concave-convex pattern shape on the imprint resin having the second concave-convex pattern shape, wherein the barrier layer contains nickel or aluminum oxide.

[0008] According to the above configuration or manufacturing method, by providing a barrier layer on the resin portion, it is possible to prevent the resin portion from coming into contact with the imprint resin when the shape of the concave-convex pattern portion is transferred to the imprint resin. This makes it possible to suppress deformation of the concave-convex pattern portion due to penetration of components such as moisture and oil contained in the imprint resin into the resin portion when repeated transfer to the imprint resin using an imprint mold is performed. When the barrier layer is made of nickel, the mechanical strength and chemical stability of the barrier layer are ensured, while deformation and peeling of the barrier layer due to deformation of the resin portion are preferably suppressed compared to when the barrier layer is made of other metals such as chromium. When the barrier layer is made of aluminum oxide, it is possible to further increase the surface hardness of the concave-convex pattern portion, while suppressing deformation and peeling of the barrier layer due to deformation of the resin portion compared to when the barrier layer is made of silicon dioxide, another inorganic oxide.

[0009] In the above-described imprint mold, the concave-convex pattern portion may have unit shapes repeatedly arranged along a first direction, the unit shapes including a convex portion extending in a second direction intersecting the first direction, the convex portion including an apex extending in the second direction, a first surface located on one side of the apex in the first direction and including the barrier layer formed on the resin portion, and a second surface located on the other side of the apex in the first direction and including the resin portion exposed from the barrier layer.

[0010] In the above-mentioned method for manufacturing an imprint mold, the imprint resin may form the second uneven pattern shape by repeatedly arranging unit resin shapes along a first direction, the unit resin shapes having resin convex portions extending in a second direction intersecting the first direction, the resin convex portions having resin tops extending in the second direction, a first resin surface located on one side of the resin top in the first direction, and a second resin surface located on the other side of the resin top in the first direction, and in the step of forming the barrier layer, the barrier layer may be formed on the imprint resin so that the first resin surface of the imprint resin is covered by the barrier layer and the second resin surface of the imprint resin is exposed from the barrier layer.

[0011] According to the above configuration or manufacturing method, the barrier layer is arranged intermittently in the first direction, which reduces the force applied to the barrier layer when the resin part bends, thereby effectively suppressing deformation or peeling of the barrier layer due to deformation of the resin part.

[0012] In the imprint mold, the barrier layer may have a thickness of 5 nm or more and 100 nm or less. When the barrier layer is arranged intermittently in the first direction, making the barrier layer thickness 5 nm or more can prevent components such as solvent contained in the imprint resin from penetrating into the resin portion. Furthermore, making the barrier layer thickness 100 nm or less can suppress increases in the time and material costs required to form the barrier layer. [Effects of the Invention]

[0013] According to the present disclosure, it is possible to suppress deformation of the concave-convex pattern portion of the imprint mold caused by components such as water and oil contained in the imprint resin permeating into the resin portion of the imprint mold. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a perspective view of AR glasses to which a diffractive optical element manufactured using an imprint mold is applied. [Figure 2] FIG. 2 is a cross-sectional view of the imprint mold. [Figure 3] FIG. 3 is a cross-sectional view of a resin portion before a barrier layer is formed in the manufacturing process of an imprint mold. [Figure 4] FIG. 4 is a cross-sectional view of an imprint mold showing an example of a modified shape of the concave-convex pattern portion. [Figure 5] FIG. 5 is a cross-sectional view of an imprint mold showing a modified example of the arrangement of the barrier layer. [Figure 6] FIG. 6 is a table showing the test conditions and evaluation results of the test examples. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, an embodiment of an imprint mold and a method for manufacturing the same will be described with reference to FIGS. (Application example of a diffractive optical element manufactured using an imprint mold) First, with reference to FIG. 1, AR glasses 100 to which a diffractive optical element (DOE) is applied, which is an example of a workpiece manufactured using an imprint mold, will be described.

[0016] 1, the AR glasses 100 include a temple unit 101 and a glass unit 102. The AR glasses 100 also include a microdisplay unit 103 that outputs an image. For example, the microdisplay unit 103 is mounted on the temple unit 101.

[0017] The glass unit 102 has optical transparency that allows visible light to pass through, and displays an image output by the microdisplay unit 103. That is, the image output by the microdisplay unit 103 is displayed on the glass unit 102 so as to be superimposed on the real space image.

[0018] Glass section 102 includes incident diffraction grating section 104, waveguide diffraction grating section 105, and exit diffraction grating section 106. Incident diffraction grating section 104, waveguide diffraction grating section 105, and exit diffraction grating section 106 are diffractive optical elements that change the traveling direction of light L1 that constitutes an image on microdisplay section 103. Incident diffraction grating section 104, waveguide diffraction grating section 105, and exit diffraction grating section 106 are manufactured using an imprint mold 10 (see FIG. 2), which will be described later, or the like.

[0019] The incident diffraction grating unit 104 introduces light L1, which constitutes an image on the microdisplay unit 103, into the glass unit 102. The waveguide diffraction grating unit 105 guides the light L1 introduced by the incident diffraction grating unit 104 to an arbitrary position within the glass unit 102. At this time, the waveguide diffraction grating unit 105 guides the light L1 so as to enlarge the image on the microdisplay unit 103. The arbitrary position within the glass unit 102 is a position within the glass unit 102 that is visible to a wearer wearing the AR glasses 100. The exit diffraction grating unit 106 outputs the light L1 guided by the waveguide diffraction grating unit 105 toward the wearer. In FIG. 1, the flow of movement of the light L1, which constitutes an image on the microdisplay unit 103, is indicated by arrows.

[0020] (Imprint Mold 10) The imprint mold 10 will be described with reference to Fig. 2. The imprint mold 10 is used, for example, to transfer a fine pattern to a diffractive optical element that is applied to AR glasses 100. The imprint mold 10 can also be used to transfer a fine pattern to a replica mold that serves as a duplication plate for transferring the fine pattern to the diffractive optical element.

[0021] It should be noted that the workpiece of the imprint mold 10 is not limited to the diffractive optical element applied to the AR glasses 100. For example, the workpiece of the imprint mold 10 may be a diffractive optical element used in other devices such as a display, recording media, biochip, optical device, diffraction grating device, Fresnel lens, lenticular lens, or microlens. The workpiece of the imprint mold 10 may be any article other than a diffractive optical element that requires a fine pattern.

[0022] The imprint mold 10 is, for example, a master mold manufactured by photolithography, or may be a replica mold obtained by transferring a master mold.

[0023] The imprint mold 10 has a concave-convex pattern portion 10P. The concave-convex pattern portion 10P has unit shapes U1 that are repeatedly arranged along a first direction D1 at a predetermined pitch P1. The pitch P1 is, for example, not less than 300 nm and not more than 500 nm. A shape that is the inverse of the shape of the concave-convex pattern portion 10P is transferred onto a workpiece of the imprint mold 10.

[0024] The unit shape U1 includes a protrusion 11 and a bottom surface 12 extending in a second direction D2 intersecting with the first direction D1. As an example, the second direction D2 is a direction perpendicular to the first direction D1, and is the depth direction of the paper in FIG. 2. The first direction D1 and the second direction D2 are parallel to the plane in which the concave-convex pattern portion 10P extends. The height direction is defined as a third direction D3.

[0025] The protrusions 11 are ridges having a rectangular cross-sectional shape in a cross section perpendicular to the second direction D2. The bottom surfaces 12 are located between the protrusions 11 of adjacent unit shapes U1. The bottom surfaces 12 are located at the bottom of the concave-convex pattern portion 10P. The concave-convex pattern portion 10P has a line-and-space pattern.

[0026] The protrusion 11 has a top surface 13. The top surface 13 extends along the second direction D2. The top surface 13 is an example of a top portion of the unit shape U1. That is, the top surface 13 is located at the top of the concave-convex pattern portion 10P. In the unit shape U1, the height H1, which is the distance from the bottom surface 12 to the top surface 13 in the third direction D3, is, for example, 100 nm or more and 300 nm or less.

[0027] The protrusion 11 has a first surface 14 and a second surface 15. The first surface 14 and the second surface 15 are two side surfaces that are bounded by the top surface 13. That is, the first surface 14 is located on one side of the top surface 13 in the first direction D1. The second surface 15 is located on the other side of the top surface 13 in the first direction D1.

[0028] The concave-convex pattern part 10P includes a resin part 20 and a barrier layer 30. The resin part 20 has a concave-convex pattern shape. The barrier layer 30 has a shape that follows the concave-convex pattern shape of the resin part 20. In other words, the surface of the barrier layer 30 has a shape that follows the surface shape of the concave-convex pattern shape of the resin part 20. The resin part 20 may be disposed on an imprint mold substrate (not shown).

[0029] 2, the barrier layer 30 covers the entire surface of the concave-convex pattern of the resin part 20. In this case, the barrier layer 30 forms the top surface 13, first surface 14, and second surface 15, which are the surfaces of the convex portions 11, and the bottom surface 12 in the unit shape U1 of the concave-convex pattern part 10P. That is, the surface shape of the concave-convex pattern part 10P shown in FIG. 2 is determined by the surface shape of the barrier layer 30, which follows the concave-convex pattern shape of the resin part 20. The bottom surface 12, top surface 13, first surface 14, and second surface 15 may be flat or curved, may be uneven, or may be a discontinuous surface with steps.

[0030] The resin material constituting the resin part 20 includes at least one selected from the group consisting of silicone resin, PDMS resin, acrylic resin, epoxy resin, and fluorine-based resin. When the imprint mold 10 is a master mold manufactured by lithography, the resin material constituting the resin part 20 may be a photosensitive resin or an electron beam photosensitive resin used as a resist material. When the imprint mold 10 is a replica mold formed by transferring a master mold, the resin material constituting the resin part 20 may be an imprint resin material.

[0031] The barrier layer 30 is formed by depositing a material constituting the barrier layer 30 on the resin part 20, which has a concave-convex pattern formed by lithography or imprinting. The material constituting the barrier layer 30 includes metallic nickel or aluminum oxide. The method for depositing the barrier layer 30 is not particularly limited, but may be, for example, atomic layer deposition (ALD), chemical vapor deposition (CVD), sputtering, evaporation, or the like.

[0032] The barrier layer 30 covers the concave-convex pattern shape of the resin part 20, thereby preventing the resin part 20 from coming into contact with the imprinted resin when the shape of the concave-convex pattern part 10P of the imprint mold 10 is transferred to the imprinted resin, which is the workpiece. In other words, when the imprinted resin is pressed against the concave-convex pattern part 10P of the imprint mold 10, the barrier layer 30 is interposed between the resin part 20 and the imprinted resin, preventing components contained in the imprinted resin, such as moisture and oil, from penetrating into the resin part 20. This suppresses deformation of the concave-convex pattern part 10P due to penetration of components contained in the imprinted resin, such as solvents, when transfer to the imprinted resin is repeated using the imprint mold 10.

[0033] When the barrier layer 30 covers the entire surface of the concave-convex pattern of the resin part 20, the thickness T1 of the barrier layer 30 is 3 nm to 100 nm, preferably 5 nm to 50 nm. The thickness T1 of the barrier layer 30 is, for example, the average thickness of the barrier layer 30 measured in a cross-sectional view perpendicular to the second direction D2.

[0034] When the thickness T1 of the barrier layer 30 is 3 nm or more, preferably 5 nm or more, it is possible to effectively prevent components such as solvents contained in the imprinted resin from penetrating into the resin part 20. Furthermore, even if the thickness T1 of the barrier layer 30 is greater than 100 nm, it is less likely to contribute to improving the functionality of preventing components such as solvents contained in the imprinted resin from penetrating into the resin part 20 compared to when the thickness T1 of the barrier layer 30 is within the above-mentioned numerical range. On the other hand, if the thickness T1 of the barrier layer 30 is greater than 100 nm, it will increase the time required to form the barrier layer 30 and the material costs. In other words, by setting the thickness T1 of the barrier layer 30 within the above-mentioned numerical range, it is possible to effectively prevent components such as solvents contained in the imprinted resin from penetrating into the resin part 20 while suppressing increases in the time required to form the barrier layer 30 and the material costs.

[0035] The barrier layer 30 is the portion that comes into contact with the imprint resin when the shape of the concave-convex pattern portion 10P of the imprint mold 10 is transferred to the imprint resin, and therefore is required to have a relatively high hardness from the viewpoints of abrasion resistance and avoidance of mechanical damage. The barrier layer 30 is also required to have chemical resistance (corrosion resistance) to solvents and the like contained in the imprint resin. Therefore, it is desirable that the barrier layer 30 be made of a metal such as nickel (Ni) or a metal oxide such as aluminum oxide (Al2O3).

[0036] On the other hand, because the resin portion 20 is more flexible than the barrier layer 30, for example, if the barrier layer 30 has excessive brittleness, deformation of the resin portion 20 may cause deformation or peeling of the barrier layer 30. In such cases, it is desirable to configure the barrier layer 30 using a metal material, such as nickel, that has relatively high hardness, excellent corrosion resistance, and sufficient ductility. In particular, configuring the barrier layer 30 using nickel allows the barrier layer 30 to more easily conform to the deformation of the resin portion 20 compared to a case where the barrier layer 30 is configured using another metal material, such as chromium (Cr), because nickel has a lower Young's modulus than chromium. For example, the Young's modulus of chromium is approximately 290 GPa, while the Young's modulus of nickel is approximately 200 GPa. Therefore, configuring the barrier layer 30 using nickel ensures mechanical strength and chemical stability, while suppressing deformation and peeling of the barrier layer 30 due to the relatively easy conformance of nickel to the deformation of the resin portion 20.

[0037] Furthermore, when a higher hardness surface is required in the concave-convex pattern portion 10P of the imprint mold 10, it is desirable that the barrier layer 30 be made of a metal oxide such as aluminum oxide, which has a higher hardness than metal materials. For example, when comparing a barrier layer 30 made of aluminum oxide with a barrier layer 30 made of silicon dioxide (SiO2), another inorganic oxide, aluminum oxide is less brittle than silicon dioxide and has physical properties that make it less likely to break. Therefore, by making the barrier layer 30 of aluminum oxide, a higher hardness surface can be formed, while preventing deformation and peeling of the barrier layer 30 due to deformation of the resin portion 20.

[0038] (Method for manufacturing imprint mold 10) The manufacturing method of the imprint mold 10 includes a step of manufacturing a resin part 20 having a concave-convex pattern shape, and a step of forming a barrier layer 30 on the resin part 20 so that the barrier layer 30 has a shape that follows the concave-convex pattern shape of the resin part 20.

[0039] For example, when the imprint mold 10 is a master mold, an example of a process for manufacturing the resin part 20 includes a step of forming a concave-convex pattern shape in a photoresist material by exposing and developing a photoresist material coated on a substrate. For example, when the imprint mold 10 is a replica mold, an example of a process for manufacturing the resin part 20 includes a step of forming a second concave-convex pattern shape in the imprint resin by pressing the imprint resin against a master mold having a first concave-convex pattern shape. The imprint resin is pressed against the master mold in a liquid or softened state before hardening. In this state, the imprint resin is hardened by heat or light, whereby the first concave-convex pattern shape of the master mold is transferred to the imprint resin as a second concave-convex pattern shape.

[0040] FIG. 3 shows the resin part 20 before the barrier layer 30 is formed. The resin part 20 has a concave-convex pattern shape that serves as the base for the shape of the concave-convex pattern part 10P when the barrier layer 30 is formed. In detail, the resin part 20 has unit resin shapes U2 that are repeatedly arranged along the first direction D1 at a predetermined pitch P2. That is, in the resin part 20, the unit resin shapes U2 are repeatedly arranged along the first direction D1 to form the concave-convex pattern shape. The pitch P2 is equal to the pitch P1 of the concave-convex pattern part 10P.

[0041] The unit resin shape U2 includes a resin protrusion 21 extending in the second direction D2 and a resin bottom surface 22. The resin protrusion 21 is a protrusion having a rectangular cross-sectional shape in a cross-sectional view perpendicular to the second direction D2. The resin bottom surface 22 is located between the resin protrusions 21 included in adjacent unit resin shapes U2. The resin bottom surface 22 is located at the bottom of the uneven pattern shape included in the resin part 20.

[0042] The resin protrusion 21 has a resin top surface 23, a first resin surface 24, and a second resin surface 25. The resin top surface 23 extends along the second direction D2. The resin top surface 23 is an example of a resin top portion of the unit resin shape U2. That is, the resin top surface 23 is located at the top of the uneven pattern shape of the resin portion 20. The first resin surface 24 and the second resin surface 25 are two side surfaces separated by the resin top surface 23. That is, the first resin surface 24 is located on one side of the resin top surface 23 in the first direction D1. The second resin surface 25 is located on the other side of the resin top surface 23 in the first direction D1.

[0043] In the process of forming the barrier layer 30 on the resin part 20, the barrier layer 30 is formed to have a shape that matches the surface shape of the uneven pattern of the resin part 20. Any method, such as the ALD, CVD, sputtering, or vapor deposition described above, can be used in the process of forming the barrier layer 30. For example, ALD and CVD are isotropic film formation methods in which a film grows uniformly over the entire surface of the pattern of the resin part 20 through a chemical reaction. Furthermore, for example, sputtering and vapor deposition are film formation methods in which material molecules or atoms that fly linearly from a target material are deposited on the resin part 20, resulting in anisotropy in the film growth direction within the resin part 20. For example, as shown in FIG. 2 , if it is desired to form a film uniformly over all of the surfaces of the resin part 20, including the resin bottom surface 22, the resin top surface 23, the first resin surface 24, and the second resin surface 25, an isotropic film formation method that grows a film uniformly, such as ALD or CVD, is preferred.

[0044] (Effects of the embodiment) (1) By providing the barrier layer 30 on the resin part 20 to cover the concave-convex pattern shape of the resin part 20, it is possible to prevent the resin part 20 from coming into contact with the imprint resin when the shape of the concave-convex pattern part 10P of the imprint mold 10 is transferred to the imprint resin. This makes it possible to suppress deformation of the concave-convex pattern part 10P caused by components such as moisture and oil contained in the imprint resin permeating into the resin part 20 when transfer to the imprint resin is repeated using the imprint mold 10. Furthermore, even when the imprint mold 10 is a replica mold manufactured by an imprint method, the barrier layer 30 of this embodiment can suitably prevent components such as solvents from permeating into the resin part 20.

[0045] (2) By forming the barrier layer 30 from nickel, it is possible to ensure the mechanical strength and chemical stability of the barrier layer 30. Furthermore, by forming the barrier layer 30 from nickel, it is possible to suitably suppress deformation and peeling of the barrier layer 30 due to deformation of the resin part 20, compared to when the barrier layer 30 is formed from other metals such as metal oxides, inorganic oxides, or chromium.

[0046] (3) By forming the barrier layer 30 from aluminum oxide, the hardness of the surface of the concave-convex pattern portion 10P can be increased compared to when the barrier layer 30 is formed from a metal material. Furthermore, by forming the barrier layer 30 from aluminum oxide, deformation and peeling of the barrier layer 30 due to deformation of the resin portion 20 can be suppressed compared to when the barrier layer 30 is formed from silicon dioxide, which is another inorganic oxide.

[0047] (4) When the barrier layer 30 covers the entire surface of the concave-convex pattern of the resin part 20, the thickness T1 of the barrier layer 30 is 3 nm or more, preferably 5 nm or more. This makes it possible to suitably prevent components such as the solvent contained in the imprint resin from penetrating into the resin part 20. Furthermore, the thickness T1 of the barrier layer 30 is 100 nm or less, preferably 50 nm or less. This makes it possible to suppress increases in the time and material costs required for forming the barrier layer 30.

[0048] (Example of change) The above embodiment can be modified as follows: The following modifications can be implemented in combination with each other within the scope of technical compatibility.

[0049] (Example of a change in the shape of the concave-convex pattern portion 10P) The shape of the concave-convex pattern portion 10P is not limited to a configuration having rectangular convex portions 11 as unit shapes U1. As an example, the imprint mold 40 shown in Fig. 4 has a concave-convex pattern portion 40P having a shape different from the line-and-space pattern of the concave-convex pattern portion 10P of the imprint mold 10 shown in Fig. 2.

[0050] As shown in FIG. 4, the concave-convex pattern portion 40P of the imprint mold 40 includes unit shapes U3 that are repeatedly arranged along the first direction D1 at a predetermined pitch P3. The pitch P3 is, for example, 300 nm or more and 500 nm or less. The unit shapes U3 include protrusions 41 that extend in the second direction D2. The protrusions 41 are ridges that have a triangular cross-sectional shape in a cross-sectional view perpendicular to the second direction D2. The concave-convex pattern portion 40P has a sawtooth cross-sectional shape called a blazed shape due to the multiple unit shapes U3 arranged in the first direction D1.

[0051] The protrusion 41 includes a vertex 42, a first surface 43, and a second surface 44. The vertex 42 extends along the second direction D2. The vertex 42 is an example of a top portion included in the unit shape U3. That is, the vertex 42 is located at the top of the concave-convex pattern portion 40P. The first surface 43 and the second surface 44 are two surfaces bounded by the vertex 42. The vertex 42 is the intersection of the upper end of the first surface 43 and the upper end of the second surface 44. That is, the first surface 43 is located on one side of the vertex 42 in the first direction D1. The second surface 44 is located on the other side of the vertex 42 in the first direction D1. As an example, the first surface 43 is an inclined surface that is inclined in the first direction D1 with respect to a plane including the first direction D1 and the second direction D2. The second surface 44 is a stepped surface that is closer to being parallel to the third direction D3 than the first surface 43. The concave-convex pattern portion 40P also has valleys 45 located between the convex portions 41 of adjacent unit shapes U3. The valleys 45 are the intersections of the lower ends of the first surface 43 and the second surface 44. The valleys 45 are located at the bottom of the concave-convex pattern portion 40P.

[0052] The concave-convex pattern portion 40P includes a resin portion 20 and a barrier layer 30. In the example shown in FIG. 4, the barrier layer 30 covers the entire surface of the concave-convex pattern shape of the resin portion 20. In this case, the barrier layer 30 forms a first surface 43 and a second surface 44, which are surfaces of the convex portions 41, in the unit shape U3 of the concave-convex pattern portion 40P. The first surface 43 and the second surface 44 may be flat, curved, uneven, or discontinuous with steps. The above-described effects can also be obtained with an imprint mold 40 including such a concave-convex pattern portion 40P.

[0053] (Example of modified arrangement of barrier layer 30) The barrier layer 30 does not need to cover the entire surface of the concave-convex pattern of the resin part 20, but only needs to cover at least a portion of the concave-convex pattern of the resin part 20. As an example, the imprint mold 50 shown in Fig. 5 has a concave-convex pattern part 50P in which the arrangement of the barrier layer 30 is different from that of the imprint mold 10 shown in Fig. 2.

[0054] 5, the concave-convex pattern portion 50P of the imprint mold 50 includes unit shapes U4 that are repeatedly arranged along the first direction D1 at a predetermined pitch (for example, pitch P1). Each unit shape U4 includes a protrusion 51 extending in the second direction D2 and a bottom surface 52. The protrusion 51 is a ridge having a rectangular cross-sectional shape in a cross-sectional view perpendicular to the second direction D2. In other words, the concave-convex pattern portion 50P has a line-and-space pattern.

[0055] The protrusion 51 has a top surface 53, a first surface 54, and a second surface 55. The top surface 53 extends along the second direction D2. The top surface 53 is an example of a top portion of the unit shape U4. That is, the top surface 53 is located at the top of the concave-convex pattern portion 50P. The first surface 54 and the second surface 55 are two surfaces that share the top surface 53 as a boundary. That is, the first surface 54 is located on one side of the top surface 53 in the first direction D1. The second surface 55 is located on the other side of the top surface 53 in the first direction D1.

[0056] The concave-convex pattern portion 50P includes a resin portion 20 and a barrier layer 30. In the example shown in FIG. 5, the barrier layer 30 covers only a portion of the concave-convex pattern of the resin portion 20 in the unit shape U4. In other words, the resin portion 20 includes a portion that is exposed from the barrier layer 30 in the unit shape U4. In this case, the barrier layer 30 is arranged intermittently in the first direction D1. The barrier layer 30 covers the resin top surface 23 and the first resin surface 24 in the unit shape U4.

[0057] In this case, the resin bottom surface 22 of the resin part 20 forms the bottom surface 52 of the unit shape U4 of the concave-convex pattern part 50P. Furthermore, the second resin surface 25 of the resin part 20 forms the second surface 55, which is the surface of the convex part 51, of the unit shape U4 of the concave-convex pattern part 50P. The barrier layer 30 forms the top surface 53, which is the surface of the convex part 51, and the first surface 54 of the unit shape U4 of the concave-convex pattern part 50P. That is, in this case, in the concave-convex pattern part 50P, the bottom surface 52 and the second surface 55 include a part of the resin part 20 exposed from the barrier layer 30. Meanwhile, the top surface 53 and the first surface 54 include the barrier layer 30 formed on the resin part 20. The bottom surface 52, the top surface 53, the first surface 54, and the second surface 55 may be flat, curved, uneven, or discontinuous.

[0058] In the imprint mold 50, the resin part 20 is likely to deform so as to be curved along the first direction D1 in which the unit shapes U4 are arranged. For example, in the imprint mold 50, the resin part 20 is likely to deform along the first curve direction CD1 in which adjacent convex portions 51 move away from each other, or along the second curve direction CD2 in which adjacent convex portions 51 move toward each other. For example, when the resin part 20 is curved along the first curve direction CD1, if a barrier layer 30 is provided over the entire surface of the concave-convex pattern shape of the resin part 20, a tensile force along the first direction D1 is likely to be applied to the barrier layer 30. For example, when the resin part 20 is curved along the second curve direction CD2, if a barrier layer 30 is provided over the entire surface of the concave-convex pattern shape of the resin part 20, a compressive force along the first direction D1 is likely to be applied to the barrier layer 30. Therefore, if the barrier layer 30 were provided over the entire surface of the concave-convex pattern of the resin part 20, tensile and compressive forces would be easily applied as the resin part 20 curves, and the barrier layer 30 would be easily deformed or peeled off as the resin part 20 deforms. In this regard, by arranging the barrier layer 30 intermittently in the first direction D1, it becomes difficult for force to be applied to the barrier layer 30 when the resin part 20 curves. Therefore, deformation and peeling of the barrier layer 30 due to deformation of the resin part 20 can be suppressed.

[0059] When the barrier layer 30 is disposed intermittently in the first direction D1, it is preferable to make the thickness T1 of the barrier layer 30 larger than when the barrier layer 30 is provided over the entire surface of the concave-convex pattern shape of the resin part 20. As an example, when the barrier layer 30 is disposed intermittently in the first direction D1, the thickness T1 of the barrier layer 30 is 5 nm or more and 100 nm or less, preferably 5 nm or more and 50 nm or less.

[0060] The method for manufacturing the imprint mold 50 includes a step of forming the barrier layer 30 on the resin portion 20 so that the resin top surface 23 and the first resin surface 24 are covered with the barrier layer 30 and the resin bottom surface 22 and the second resin surface 25 are exposed from the barrier layer 30. When anisotropy is to be generated in the growth direction of the barrier layer 30 in the resin portion 20, a film formation method with high anisotropy in the film growth direction, such as a sputtering method or a vapor deposition method, is preferred. For example, the material constituting the barrier layer 30 is sputtered obliquely with respect to the resin portion 20 along the sputtering direction SD1 indicated by the arrow in FIG. 5 . This allows the barrier layer 30 to be formed on the resin portion 20 so that the resin top surface 23 and the first resin surface 24 are covered with the barrier layer 30 and the resin bottom surface 22 and the second resin surface 25 are exposed from the barrier layer 30.

[0061] The configuration in which the barrier layer 30 is intermittently arranged in the first direction D1 can also be applied to the imprint mold 40 having the blazed shape shown in Fig. 4. For example, in the unit shape U3 of the concave-convex pattern portion 40P provided in the imprint mold 40, one of the first surface 43 and the second surface 44 may be formed by the barrier layer 30, and the resin portion 20 may be exposed from the barrier layer 30 on the other surface. That is, in the configuration in which the barrier layer 30 is intermittently arranged in the first direction D1, in the unit resin shape U2, the barrier layer 30 may be provided only on one of the first resin surface 24 and the second resin surface 25 that sandwich the resin top portion.

[0062] (Other change examples) The thickness T1 of the barrier layer 30 is not limited as long as it can effectively suppress deformation of the concave-convex pattern portion 10P due to penetration of components such as water and oil contained in the imprint resin. For example, even when the barrier layer 30 is provided over the entire surface of the concave-convex pattern shape of the resin portion 20, the thickness T1 of the barrier layer 30 may be less than 3 nm or more than 100 nm. For example, even when the barrier layer 30 is disposed intermittently in the first direction D1, the thickness T1 of the barrier layer 30 may be less than 5 nm or more than 100 nm.

[0063] A release layer may be provided on the upper layer of the concave-convex pattern portion 10P of the imprint mold 10. The release layer has a lower surface energy than the barrier layer 30 (or the resin portion 20) that constitutes the concave-convex pattern portion 10P. One example of the release layer is made of a fluoropolymer. Specifically, a solution of a silane coupling agent is applied to the mold surface to form a film made of a fluoropolymer with low surface energy on the mold surface. In this way, providing a release layer can prevent poor release of the imprint resin as the workpiece.

[0064] (Test example) The following describes test examples using the imprint molds 10 and 50. Note that the following test examples are examples for explaining the effects of the above-described embodiment, and do not limit the present disclosure.

[0065] In the following test examples, a resin mold having a rectangular line-and-space pattern was used as a sample. The sample used in the test examples was a replica mold in which a concave-convex pattern shape was transferred from a master mold to the resin part 20 using an imprinting method. An acrylic resin (product name: PAK-TRAD03, manufactured by Toyo Gosei Co., Ltd.) was used as the imprint resin serving as the replica material constituting the resin part 20. In the test examples, 24 levels of samples were fabricated in which barrier layers 30 of different configurations were formed on the resin part 20 configured as described above. For comparison, a resin mold in which no barrier layer 30 was formed on the resin part 20 was fabricated as sample x1. The line-and-space pattern had a convex line width of 200 nm, a bottom width of 200 nm, and a height of 260 nm.

[0066] (Samples a1 to a6) In the test examples, samples a1 to a6 were fabricated using aluminum oxide as the material for the barrier layer 30. In samples a1 to a6, the entire surface of the concave-convex pattern shape of the resin part 20 was covered with the barrier layer 30 by ALD. The thickness T1 of the barrier layer 30 was 2 nm, 3 nm, 5 nm, 10 nm, 50 nm, and 100 nm in the order of samples a1 to a6.

[0067] (Samples b1 to b6) In the test examples, samples b1 to b6 were prepared using aluminum oxide as the material for the barrier layer 30. In samples b1 to b6, the resin portion 20 was sputtered obliquely to cover the resin top surface 23 and the first resin surface 24 of the concave-convex pattern of the resin portion 20 with the barrier layer 30. In other words, the resin bottom surface 22 and the second resin surface 25 of the concave-convex pattern of the resin portion 20 were exposed from the barrier layer 30. The thickness T1 of the barrier layer 30 was 2 nm, 3 nm, 5 nm, 10 nm, 50 nm, and 100 nm in the order of samples b1 to b6.

[0068] (Samples c1 to c6) In the test examples, samples c1 to c6 were prepared using nickel as the material for the barrier layer 30. In samples c1 to c6, the entire surface of the concave-convex pattern shape of the resin part 20 was covered with the barrier layer 30 by ALD. The thickness T1 of the barrier layer 30 was 2 nm, 3 nm, 5 nm, 10 nm, 50 nm, and 100 nm in the order of samples c1 to c6.

[0069] (Samples d1 to d6) In the test examples, samples d1 to d6 were prepared using nickel as the material for the barrier layer 30. In samples d1 to d6, the resin portion 20 was sputtered from an oblique direction, so that the resin top surface 23 and the first resin surface 24 of the concave-convex pattern of the resin portion 20 were covered with the barrier layer 30. That is, the resin bottom surface 22 and the second resin surface 25 of the concave-convex pattern of the resin portion 20 were exposed from the barrier layer 30. The thickness T1 of the barrier layer 30 was 2 nm, 3 nm, 5 nm, 10 nm, 50 nm, and 100 nm in the order of samples d1 to d6.

[0070] (evaluation) For each of the resin molds produced, the amount of dimensional change of the workpiece when the pattern shape was repeatedly transferred by the imprint method was evaluated.

[0071] Specifically, pattern transfer to the imprint resin was repeated 20 times using each prepared resin mold. The ratio of the difference between the dimensions of the workpiece transferred the first time and the dimensions of the workpiece transferred the 20th time was calculated relative to the dimensions of the workpiece transferred the first time. In other words, the ratio of the dimensional change of the workpiece that occurred from the first transfer to the 20th transfer was calculated based on the dimensions of the workpiece transferred the first time. The dimensions evaluated were the height and line width of the convex portions of the line-and-space pattern. The imprint resin used as the workpiece was an acrylic resin (product name: PAK-TRAD03, manufactured by Toyo Gosei Co., Ltd.), the same material as that used for the resin mold. The dimensions were measured using a scanning probe microscope (manufactured by Hitachi High-Tech Corporation) in a cross-sectional view perpendicular to the second direction D2 in which the convex portions extend.

[0072] If the amount of dimensional change in the workpiece that occurred between the first and 20th transfers was 2% or more of the dimensions of the workpiece that was transferred the first time, the score was 1 point. If the amount of dimensional change in the workpiece that occurred between the first and 20th transfers was 1% or more but less than 2% of the dimensions of the workpiece that was transferred the first time, the score was 2 points. If the amount of dimensional change in the workpiece that occurred between the first and 20th transfers was less than 1% of the dimensions of the workpiece that was transferred the first time, the score was 3 points. The evaluation results are shown in Figure 6.

[0073] In sample x1, the dimensional change of the workpiece that occurred from the first transfer to the twentieth transfer was 2% or more of the dimension of the workpiece that was transferred the first time. That is, in sample x1, which did not have the barrier layer 30, dimensional changes in the height and line width of the workpiece due to repeated transfer were confirmed.

[0074] For sample a1, the dimensional change of the workpiece from the first transfer to the twentieth transfer was 2% or more of the dimensions of the workpiece at the first transfer. For sample a2, the dimensional change of the workpiece from the first transfer to the twentieth transfer was 1% or more but less than 2% of the dimensions of the workpiece at the first transfer. For samples a3 to a6, the dimensional change of the workpiece from the first transfer to the twentieth transfer was less than 1% of the dimensions of the workpiece at the first transfer. The results for samples a1 to a6 confirmed that covering the entire surface of the concave-convex pattern shape of the resin part 20 with a barrier layer 30 made of aluminum oxide and having a thickness T1 of 3 nm or more can reduce the dimensional change of the workpiece due to repeated transfer. In particular, it was confirmed that the dimensional change of the workpiece due to repeated transfer can be suitably reduced if the thickness T1 of the barrier layer 30 made of aluminum oxide is 5 nm or more.

[0075] For samples b1 and b2, the amount of dimensional change of the workpiece that occurred from the first transfer to the twentieth transfer was 2% or more of the dimensions of the workpiece that was transferred the first time. For samples b3 to b6, the amount of dimensional change of the workpiece that occurred from the first transfer to the twentieth transfer was 1% or more and less than 2% of the dimensions of the workpiece that was transferred the first time. The results for samples b1 to b6 confirmed that the amount of dimensional change of the workpiece due to repeated transfers can be reduced by covering the resin top surface 23 and first resin surface 24 of the resin part 20 with a barrier layer 30 made of aluminum oxide and having a thickness T1 of 5 nm or more.

[0076] For sample c1, the dimensional change of the workpiece from the first transfer to the twentieth transfer was 2% or more of the dimensions of the workpiece at the first transfer. For sample c2, the dimensional change of the workpiece from the first transfer to the twentieth transfer was 1% or more but less than 2% of the dimensions of the workpiece at the first transfer. For samples c3 to c6, the dimensional change of the workpiece from the first transfer to the twentieth transfer was less than 1% of the dimensions of the workpiece at the first transfer. The results for samples c1 to c6 confirmed that covering the entire surface of the concave-convex pattern shape of the resin part 20 with a nickel barrier layer 30 having a thickness T1 of 3 nm or more can reduce the dimensional change of the workpiece due to repeated transfer. In particular, it was confirmed that the dimensional change of the workpiece due to repeated transfer can be effectively reduced if the nickel barrier layer 30 has a thickness T1 of 5 nm or more.

[0077] For samples d1 and d2, the amount of dimensional change in the workpiece that occurred from the first transfer to the twentieth transfer was 2% or more of the dimensions of the workpiece that was transferred the first time. For samples d3 to d6, the amount of dimensional change in the workpiece that occurred from the first transfer to the twentieth transfer was 1% or more and less than 2% of the dimensions of the workpiece that was transferred the first time. The results for samples d1 to d6 confirmed that the amount of dimensional change in the workpiece due to repeated transfers can be reduced by covering the resin top surface 23 and first resin surface 24 of the resin part 20 with a barrier layer 30 made of nickel and having a thickness T1 of 5 nm or more. [Explanation of symbols]

[0078] D1…first direction D2…Second direction T1...Thickness U1, U3, U4...Unit shape U2...Unit resin shape 10, 40, 50...Imprint mold 10P, 40P, 50P...Concave and convex pattern 11, 41, 51...Convex parts 14,43,54…First page 15,44,55…Second side 20...Resin part 21...Resin protrusion 24...First resin surface 25…Second resin surface 30...Barrier layer

Claims

1. An imprint mold having a concave-convex pattern portion, the concave-convex pattern portion includes a resin portion having a concave-convex pattern shape, and a barrier layer formed on the resin portion and having a shape following the concave-convex pattern shape, The barrier layer comprises nickel or aluminum oxide. Imprint mold.

2. The concave-convex pattern portion includes unit shapes repeatedly arranged along a first direction, the unit shape includes a protrusion extending in a second direction intersecting the first direction, The convex portion includes an apex extending in the second direction, a first surface located on one side of the apex in the first direction and including the barrier layer formed on the resin portion, and a second surface located on the other side of the apex in the first direction and including the resin portion exposed from the barrier layer. The imprint mold of claim 1 .

3. The barrier layer has a thickness of 5 nm to 100 nm. The imprint mold according to claim 1 or 2.

4. A method for manufacturing an imprint mold, comprising: a step of pressing an imprint resin against a master mold having a first concave-convex pattern shape to form a second concave-convex pattern shape by transferring the first concave-convex pattern shape to the imprint resin; forming a barrier layer having a shape that follows the second concave-convex pattern shape on the imprint resin having the second concave-convex pattern shape, The barrier layer comprises nickel or aluminum oxide. A method for manufacturing an imprint mold.

5. the imprinted resin has unit resin shapes repeatedly arranged along a first direction to form the second concave-convex pattern shape; the unit resin shape includes a resin protrusion extending in a second direction intersecting the first direction, the resin convex portion includes a resin apex portion extending in the second direction, a first resin surface located on one side of the resin apex portion in the first direction, and a second resin surface located on the other side of the resin apex portion in the first direction, In the step of forming the barrier layer, the barrier layer is formed on the imprinted resin so that the first resin surface of the imprinted resin is covered with the barrier layer and the second resin surface of the imprinted resin is exposed from the barrier layer. The method for manufacturing an imprint mold according to claim 4 .

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