JP6946940B2 - Method for manufacturing imprint mold, blank for forming imprint mold, and pattern transfer body - Google Patents

Description

The present invention relates to an imprint mold, a blank used for forming the imprint mold, and a method for producing a pattern transfer body using the imprint mold.

In nanoimprint lithography, a desired transfer pattern provided on an imprint mold is brought into close contact with a curable resin layer applied to the surface of an object to be transferred, and an external stimulus such as heat or light is applied to the pattern on the curable resin layer. This is a method of transferring a pattern to an object to be transferred through a step of transferring the pattern. Nanoimprint lithography is expected as a next-generation lithography technique for LSI manufacturing because a pattern can be formed by a simple method. Further, it is expected as a technology for processing optical parts, light emitting elements, photoelectric conversion elements, biosensors, decorations, beverage containers, food containers and the like. Examples of such a basic technique for nanoimprint lithography include those described in Patent Document 1.

Among the nanoimprint lithography, the optical nanoimprint lithography has advantages as compared with the thermal nanoimprint lithography, such as high throughput, no dimensional change due to temperature, and easy alignment of the imprint mold. Therefore, in recent years, the development of imprint molds for optical nanoimprint lithography has been promoted.

As the imprint mold for optical nanoimprint lithography, a mold having a mesa structure provided substantially in the center of the surface side is often used. In such an imprint mold, by providing the transfer pattern on the surface of the mesa structure, it is possible to prevent the outer region of the transfer pattern from coming into contact with the curable resin layer of the transferred body.

In optical nanoimprint lithography, the curable resin is applied and the transfer pattern of the imprint mold is transferred to the curable resin multiple times in succession on the region of a plurality of patterns on the surface of the object to be transferred. The method is used. In the step-and-repeat method, in one transfer of the pattern to the curable resin, the exposure light transmitted through the outer region of the transfer pattern in the imprint mold causes the outside of the region of one pattern on the surface of the transferred object. The curable resin that oozes out may be cured. In particular, when the imprint mold provided with the above-mentioned mesa structure is used, the curable resin exuded to the outside of the region for one pattern is cured by the exposure light transmitted around and on the side surface of the mesa structure. I sometimes did.

As a result, the cured resin is formed up to the region of the other adjacent pattern on the surface of the transferred body, which may make the subsequent transfer to the region of the other adjacent pattern difficult. rice field. Therefore, the width between adjacent patterns on the surface of the transferred body cannot be reduced. For example, when an LSI chip is manufactured on the transferred body, one chip is equivalent to one pattern. Since it is formed by transfer, there is a problem that the number of chips obtained from one transferred body cannot be increased. Furthermore, the resin that has exuded to the outside of the region of one pattern is cured in a raised shape, so that the imprint mold is cured of the cured resin during the subsequent transfer to the region of another adjacent pattern. There was also a problem that it was damaged by contact with the resin, and particles were generated due to the cured resin.

As a method for dealing with such a problem, for example, Patent Document 2 can prevent the curable resin exuded to the outside of the region of one pattern on the surface of the transferred body from being cured. As described above, a transfer method using an imprint mold provided with a light-shielding film for preventing the exposure light from passing through the periphery and the side surface of the mesa structure is described.

In the transfer method described in Patent Document 2, the pattern is transferred to the curable resin layer provided on the surface of the transferred body by the transfer method as shown in FIGS. 21 (a) to 21 (d). ..

Specifically, first, as shown in FIG. 21A, the curable resin layer 2 is applied to the surface 1a of the transferred body 1, and the imprint mold 10 is prepared. The imprint mold 10 includes a light transmissive substrate 20 having a front surface 20a and a back surface 20b, a mesa structure 22 is provided on the front surface 20a side of the light transmissive substrate 20, and a transfer pattern 24 is provided on the surface 22a of the mesa structure 22. Has been done. On the back surface 20b side of the light transmissive substrate 20, a recess 26 is provided in a region including the entire mesa structure region M in which the mesa structure 22 is provided in a plan view. A light-shielding film 40a is provided around the mesa structure 22 on the surface 20a of the light-transmitting substrate 20, and a light-shielding film 40b is provided on the side surface 22b of the mesa structure 22.

Next, as shown in FIG. 21B, the imprint mold 10 is brought into close contact with the curable resin layer 2 so that the transfer pattern 24 provided on the surface 22a of the mesa structure 22 is in contact with the curable resin layer 2. At this time, on the surface 1a of the transferred body 1, a part of the curable resin 2b may be extruded by the mesa structure 22 and seep out of the region of one pattern.

Next, as shown in FIG. 21C, the curable resin layer 2 is formed by injecting the exposure light into the mesa structure region M from the back surface 20b side of the light transmissive substrate 20 in a state where the two are in close contact with each other. To cure.

Next, as shown in FIG. 21D, the imprint mold 10 is peeled off from the resin layer. As a result, the transfer pattern 24 is transferred to form a cured resin layer 2'.

In the transfer method shown in FIG. 21, in the imprint mold 10, the light-shielding film 40a and the light-shielding film 40b are provided around the mesa structure 22 and on the side surface 22b, so that the light-shielding film 40a and the light-shielding film 40b are provided at the time of exposure shown in FIG. 21 (c). Preventing the scattered exposure light from passing through the periphery of the mesa structure 22 and the side surface 22b, the curable resin 2b exuding to the outside of the region for one pattern is exposed and cured. I'm trying to suppress it.

However, as shown in FIG. 22 in which the region A shown in FIG. 21C is enlarged, the light-shielding film 40b on the side surface 22b of the mesa structure 22 uniformly forms the light-shielding film 40b on the side surface 22b of the mesa structure 22. Defects 42 may form because it is difficult to do. Therefore, the scattered exposure light is transmitted from the side surface 22b of the mesa structure 22 through the defect 42, so that the curable resin 2b exuded to the outside of the region for one pattern is exposed and cured. It could not be suppressed sufficiently. As a result, as shown in FIG. 21D, a resin 2b ′ obtained by curing the curable resin 2b that has exuded to the outside of the region for one pattern may be formed, which is a problem as described above. Was sometimes not fully resolved.

U.S. Pat. No. 5,772,905 JP-A-2010-245470

The present invention has been made in view of the above problems, and by reducing or preventing the transmission of exposure light from the side surface of the mesa structure, the outside of the region of one pattern on the surface of the object to be transferred. An object of the present invention is to provide a method for producing an imprint mold, a blank for forming an imprint mold, and a pattern transfer body, which can suppress exposure of the exuded curable resin.

In order to solve the above problems, the present invention includes a light transmissive substrate having a front surface and a back surface, a mesa structure is provided on the front surface side of the light transmissive substrate, and a region where the mesa structure is provided. The mesa structure region, which is a region that coincides in a plan view, has a characteristic of refracting incident light incident from the back surface side of the light transmissive substrate toward the center side of the mesa structure region. I will provide a.

According to the present invention, it is possible to reduce the transmission of exposure light from the side surface of the above-mentioned mesa structure.

In the above invention, the back surface side of the light transmissive substrate in the mesa structure region is provided with a shape in which incident light incident from the back surface side of the light transmissive substrate is refracted toward the center side of the mesa structure region. The convex lens shape portion to have may be provided.

In this case, it is preferable that the convex lens shape portion is provided in a region including the outer peripheral portion of the mesa structure region. This is because it effectively prevents the exposure light from being transmitted from the side surface of the mesa structure.

Further, in the above invention, the mesa structure region of the light transmissive substrate may be provided with a refractive index changing portion in which the refractive index continuously increases toward the center side of the mesa structure region.

In this case, it is preferable that the refractive index changing portion is provided in a region including the outer peripheral portion of the mesa structure region. This is because it effectively prevents the exposure light from being transmitted from the side surface of the mesa structure.

Further, in the above invention, it is preferable that a recess is provided in the region including the mesa structure region on the back surface side of the light transmissive substrate. This is because it is possible to suppress the encapsulation of air between the transfer pattern and the curable resin layer.

Further, in the above invention, it is preferable that a light-shielding film is provided around the mesa structure on the surface of the light-transmitting substrate. This is because it is possible to prevent the exposure light from being transmitted from the periphery of the mesa structure.

Further, in the above invention, it is preferable that a light-shielding film is provided around the mesa structure region on the back surface of the light-transmitting substrate. This is because it is possible to prevent the exposure light from being transmitted from the periphery of the mesa structure region.

Further, in the above invention, a transfer pattern may be provided on the surface of the above mesa structure.

Further, the present invention is the imprint mold forming blank used for the above-mentioned imprint mold, and the above-mentioned mesa structure is formed in the region of the above-mentioned imprint mold forming blank which becomes the above-mentioned mesa structure region. Provided is a blank for forming an imprint mold, which is provided with a refractive index changing portion in which the refractive index continuously increases toward the center side of the region.

According to the present invention, it is possible to manufacture an imprint mold capable of reducing or preventing the transmission of exposure light from the side surface of the mesa structure.

The present invention also provides a method for producing a pattern transfer body, which comprises a transfer step of transferring the transfer pattern of the imprint mold described above to a curable resin layer provided on the surface of the transfer body. ..

According to the present invention, by preventing the exposure light from being transmitted from the side surface of the mesa structure, the curable resin exuded to the outside of the region of one pattern on the surface of the transferred body is exposed. This can be sufficiently suppressed.

In the present invention, there is an effect that the curable resin exuded to the outside of the region of one pattern on the surface of the transferred body can be sufficiently suppressed from being cured.

It is the schematic which shows an example of the imprint mold of 1st Embodiment. It is the schematic sectional drawing which shows the other example of the imprint mold of 1st Embodiment. It is the schematic sectional drawing which shows the other example of the imprint mold of 1st Embodiment. It is the schematic sectional drawing which shows the other example of the imprint mold of 1st Embodiment. It is the schematic sectional drawing which shows the other example of the imprint mold of 1st Embodiment. It is the schematic which shows an example of the imprint mold of 2nd Embodiment. It is the schematic sectional drawing which shows the other example of the imprint mold of 2nd Embodiment. It is the schematic sectional drawing which shows the other example of the imprint mold of 2nd Embodiment. It is the schematic sectional drawing which shows the other example of the imprint mold of 2nd Embodiment. It is the schematic sectional drawing which shows the other example of the imprint mold of 2nd Embodiment. It is the schematic sectional drawing which shows the other example of the imprint mold of 2nd Embodiment. It is schematic process sectional drawing which shows an example of the manufacturing method of the blank for imprint mold formation of 2nd Embodiment. It is a schematic process sectional view which shows another example of the manufacturing method of the blank for imprint mold formation of 2nd Embodiment. It is a schematic process sectional view which shows another example of the manufacturing method of the blank for imprint mold formation of 2nd Embodiment. It is a schematic process sectional view which shows another example of the manufacturing method of the blank for imprint mold formation of 2nd Embodiment. It is the schematic sectional drawing which shows an example of the imprint mold of another embodiment. It is the schematic which shows an example of the blank for imprint mold formation of this invention. It is a schematic process sectional view which shows an example of the manufacturing method of the blank for imprint mold formation of this invention. It is a schematic process sectional view which shows an example of the manufacturing method of the pattern transfer body of this invention. It is an enlarged view of the region A shown in FIG. 19 (c). It is a schematic process sectional view which shows an example of the manufacturing method of the pattern transfer body of the prior art. It is an enlarged view of the region A shown in FIG. 21 (c).

Hereinafter, the method for producing the imprint mold, the blank for forming the imprint mold, and the pattern transfer body of the present invention will be described in detail.

A. Imprint mold The imprint mold of the present invention includes a light-transmitting substrate having a front surface and a back surface, a mesa structure is provided on the front surface side of the light-transmitting substrate, and a region and a plane on which the mesa structure is provided. The mesa structure region, which is a visually coincident region, is characterized by having a property of refracting incident light incident from the back surface side of the light transmissive substrate toward the center side of the mesa structure region.

The imprint mold of the present invention can be roughly classified into the first embodiment and the second embodiment according to the difference in the configuration for realizing the above-mentioned property of refracting the incident light. Hereinafter, the first embodiment and the second embodiment will be mainly described.

I. First Embodiment In the imprint mold of the first embodiment, incident light incident from the back surface side of the light transmissive substrate is applied to the back surface side of the light transmissive substrate in the mesa structure region. A convex lens-shaped portion having a shape to be refracted is provided on the central side of the region.

An example of the imprint mold of the first embodiment will be described with reference to the drawings. FIG. 1A is a schematic plan view showing an example of the imprint mold of the first embodiment. FIG. 1B is a cross-sectional view taken along the line AA shown in FIG. 1A. FIG. 1A is a plan view from the back surface 20b side of the light transmissive substrate 20 shown in FIG. 1B.

As shown in FIGS. 1A and 1B, the imprint mold 10 includes a light-transmitting substrate 20 having a front surface 20a and a back surface 20b, and has a mesa structure on the front surface 20a side of the light-transmitting substrate 20. 22 is provided. A transfer pattern 24 is provided on the surface 22a of the mesa structure 22. On the back surface 20b side of the light transmissive substrate 20, a recess 26 is provided in a region including the entire mesa structure region M in which the mesa structure 22 is provided in a plan view. A convex lens-shaped portion 28 having a convex curved surface 28a is provided in the entire region inside the recess 26 of the light transmissive substrate 20 in a plan view.

The convex lens shape portion 28 is provided in a region including the entire mesa structure region M and a region outside the mesa structure region M in a plan view. Therefore, the incident light incident on the mesa structure region M from the back surface 20b side of the light transmissive substrate 20 is incident on the convex lens shape portion 28, and the incident light incident on the convex lens shape portion 28 is the center of the mesa structure region M. Can be refracted to the side. In particular, since the convex lens portion 28 is provided in a region including the outer peripheral portion M _P of the mesa structure region M _(portion sandwiched between the dashed lines indicate the outer periphery of the mesa structure region M and its inner dashed line), Mesa the light incident to the outer peripheral portion M _P of the structural region M can be refracted toward the center of the mesa structure region M.

Therefore, as shown in FIGS. 19 (c) and 20 to be described later, in order to transfer the transfer pattern 24 to the transferred body 1, the curable resin layer 2 applied to the surface 1a of the transferred body 1 is messed up. The curable resin layer 2 is formed by injecting the exposure light from the back surface 20b side of the light transmissive substrate 20 into the mesa structure region M in a state where the imprint mold 10 is brought into close contact with the transfer pattern 24 in the structure 22. Since the exposure light is incident on the convex lens shape portion 28 at the time of curing, the exposure light can be refracted toward the center side of the mesa structure region M. As a result, it is possible to prevent the scattered exposure light from being transmitted from the side surface 22b of the mesa structure 22. In particular, since the exposure light incident to the outer peripheral portion M _P of the mesa structure region M can be refracted toward the center of the mesa structure region M, preventing the transmission of exposure light from the side surface 22b of the mesa structure 22 effectively Can be done. As shown in FIG. 22 described above, even when the defect 42 is formed on the light-shielding film 40b provided on the side surface 22b of the mesa structure 22, the scattered exposure light is transmitted from the side surface 22b of the mesa structure 22 through the defect 42. It is possible to prevent transmission. Therefore, even if the light-shielding film 40b is not provided on the side surface 22b of the mesa structure 22, or even if the defect 42 is formed on the light-shielding film 40b, the surface 1a of the transferred body 1 is outside the region for one pattern. It is possible to sufficiently prevent the curable resin 2b that has exuded into the surface from being exposed and cured.

Therefore, according to the first embodiment, by preventing the exposure light from being transmitted from the side surface of the mesa structure, the curable resin exuded to the outside of the region of one pattern on the surface of the transferred body. Can be sufficiently suppressed from being exposed.

1. 1. Light-transmitting substrate The light-transmitting substrate is provided with a convex lens-shaped portion having a shape of refracting incident light incident from the back surface side toward the center side of the mesa structure region on the back surface side of the mesa structure region. Is what it is.

(1) Convex lens shape portion The convex lens shape portion is a part of the light transmissive substrate provided on the back surface side in the mesa structure region.

Here, in the first embodiment, the mesa structure region means a region such as the mesa structure region M shown in FIG. 1 in which the mesa structure is provided in a plan view of the light transmissive substrate. ..

The convex lens shape portion may be any one that realizes a characteristic of refracting incident light incident on the mesa structure region from the back surface side toward the center side of the mesa structure region, and a part or the whole of the mesa structure region may be used. It may be provided in the region including the mesa structure, but as shown in FIG. 1, it is preferably provided in the region including the outer peripheral portion of the mesa structure region. This is because by refracting the incident light incident on the outer peripheral portion of the mesa structure region toward the center side of the mesa structure region, it is possible to effectively prevent the exposure light from being transmitted from the side surface of the mesa structure region. ..

Here, in the first embodiment, the outer peripheral portion of the mesa structure region, means a portion having a width on the center side from the outer periphery of the mesa structure region, such as the outer peripheral portion M _P shown in FIG.

The width of the outer peripheral portion of the mesa structure region as shown by _{W P} 1 is preferably in the range of 1Myuemu～5mm, among others within the scope of 10 .mu.m to 1 mm, in particular in the range of from 50μm~1mm Is preferable. This is because it is possible to more effectively prevent the exposure light from being transmitted from the side surface of the mesa structure. The width of the outer peripheral portion of the mesa structure region, 0.1% of the thickness minimum value of the light-transmitting substrate in the outer peripheral portion as shown by T _C in FIG. 1 (b) to 500 It is preferably in the range of%, and more preferably in the range of 1% to 200%, particularly preferably in the range of 5% to 100%. This is because it is possible to more effectively prevent the exposure light from being transmitted from the side surface of the mesa structure.

2 (a) to 2 (c) are schematic cross-sectional views showing other examples of the imprint mold of the first embodiment, respectively, and show a cross section corresponding to the cross section shown in FIG. 1 (b). Is.

In the imprint mold 10 shown in FIG. 2A, a convex lens-shaped portion 28 having a convex curved surface 28a is provided in a part of the inner region of the concave portion 26 on the back surface 20b side of the light transmissive substrate 20. There is. Convex lens shaped portion 28 is provided in a region including the whole of the mesa structure region M including the outer peripheral portion M _P.

2 In the imprint mold 10 shown in (b), only the outer peripheral portion M _P of the mesa structure region M in the region inside the recess 26 of the back surface 20b side of the light transmitting substrate 20, a convex lens shape of a Fresnel lens shape A portion 28 is provided. Inside the back surface 26b of the recess 26, the region inside the outer peripheral portion M _P of the mesa structure region M has a planar shape.

In imprint mold 10 shown in FIG. 2 (c), only the outer peripheral portion M _P of the mesa structure region M in the region inside the recess 26 of the back surface 20b side of the light transmitting substrate 20, the center of the mesa structure region M A convex lens-shaped portion 28 having an inclined surface whose side is raised is provided. Inside the back surface 26b of the recess 26, the region inside the outer peripheral portion M _P of the mesa structure region M has a planar shape.

As the convex lens-shaped portion, as shown in FIGS. 2 (b) and 2 (c), in the region inside the concave portion described in the item of “(2) Light transmissive substrate b. Recessed portion” described later. It is preferable that the mesa structure region is provided only on the outer peripheral portion. On the inner back surface of the recess, the region inside the outer peripheral portion of the mesa structure region can be formed into a planar shape. As a result, when the transfer pattern of the imprint mold is brought into close contact with the curable resin layer applied to the surface of the object to be transferred, the air pressure in the recess is increased to bend the imprint mold, thereby forming the transfer pattern. In the case of suppressing the encapsulation of air between the curable resin layer and the curable resin layer, the inner region of the outer peripheral portion has a planar shape, so that the bending method of the transfer pattern region of the imprint mold is made constant. be able to. Therefore, it becomes easy to predict the dimensional variation of the transfer pattern region, and it becomes easy to correct the dimension of the transfer pattern region that cancels the dimensional variation.

As shown in FIGS. 1 and 2A, the convex lens shape portion is provided in a region including an inner or outer region of the outer peripheral portion of the mesa structure region in the light transmissive substrate. It may be a thing. Further, the convex lens shape portion may be provided in the entire inner region of the concave portion as shown in FIG. 1, or may be provided in the entire inner region of the concave portion as shown in FIG. 2 (a). It may be provided as a part of.

FIG. 3 is a schematic cross-sectional view showing another example of the imprint mold of the first embodiment, and shows a cross section corresponding to the cross section shown in FIG. 1 (b).

In the imprint mold 10 shown in FIG. 3, the entire mesa structure region M and the outer region thereof are viewed in a plan view on the back surface 20b side of the light transmissive substrate 20 not provided with the recess 26 shown in FIG. A convex lens-shaped portion 28 having a convex curved surface 28a is provided in a region including the above.

As the convex lens shape portion, as shown in FIGS. 1 and 2 (a) to 2 (c), the inside of the concave portion described in the item of “(2) Light transmissive substrate b. Recessed portion” described later. It may be provided in the region, or may be provided on the back surface side of the light transmissive substrate which is not provided with the recess as shown in FIG. 3, but is usually inside the recess. It is provided in the area of.

The shape of the convex lens shape portion is not particularly limited as long as it is a shape that realizes the characteristic of refracting the incident light incident on the mesa structure region from the back surface side toward the center side of the mesa structure region. 1. A shape having a convex curved surface as shown in FIGS. 2 (a) and 3; a Fresnel lens shape or a prism shape as shown in FIG. 2 (b), as shown in FIG. 2 (c). Examples thereof include a shape having an inclined surface in which the central side of the mesa structure region is high, and can be appropriately selected depending on the application and the like.

The method for forming the convex lens shape portion is not particularly limited as long as the convex lens shape portion having a desired shape and size can be formed, and examples thereof include machining and etching, and the shape and size of the convex lens shape portion. In addition, it may be appropriately selected according to the material of the light transmissive substrate and the like. Further, as a method for forming the convex lens shape portion, a method of mirror-finishing the convex lens shape portion at the finishing stage is preferable. This is because particles generated from the light-transmitting substrate can be removed when the convex lens-shaped portion is formed, and particles can be prevented from adhering to the convex lens-shaped portion from the outside.

(2) Light transmissive substrate a. Mesa structure The plan-viewed shape of the mesa structure is not particularly limited, and may be, for example, a rectangular shape as shown in FIG. The height of the mesa structure as shown by H in FIG. 1B varies depending on the application and the like, but is, for example, about 10 μm to 50 μm. Further, the vertical and horizontal lengths of the rectangular mesa structure in a plan view vary depending on the application and the like, and are, for example, about 20 mm to 35 mm, but are not limited to this range.

Examples of the method for forming the mesa structure include wet etching using an etching mask.

b. Recessed light-transmitting substrate may be provided with a recessed portion in the region including the mesa structure region on the back surface side as shown in FIGS. 1 and 2 (a) to 2 (c). Alternatively, as shown in FIG. 3, the recessed portion may not be provided, but the recessed portion is preferably provided. When the transfer pattern of the imprint mold is brought into close contact with the curable resin layer applied to the surface of the transferred body, the transfer pattern and the curable resin layer are formed by increasing the air pressure in the recess to bend the imprint mold. This is because it is possible to prevent air from being sealed between the two.

The shape of the concave portion in a plan view is not particularly limited, and may be circular, for example, as shown in FIG. The residual thickness of the light-transmitting substrate after drilling the recess is, for example, about 0.5 mm or more, and the diameter of the circular recess is, for example, about 80 mm.

Examples of the method for forming the recesses include machining, and the recesses may be appropriately selected depending on the shape and size of the recesses, the material of the light-transmitting substrate, and the like. When the convex lens shape portion is provided in the inner region of the concave portion, a method of forming the concave portion and the convex lens shape portion together can be used.

c. Transfer Pattern FIG. 4 is a schematic cross-sectional view showing another example of the imprint mold of the first embodiment, and shows a cross section corresponding to the cross section shown in FIG. 1 (b).

The imprint mold 10 shown in FIG. 4 is different from the imprint mold 10 shown in FIG. 1 in that a transfer pattern is not provided on the surface of the mesa structure 22 of the light transmissive substrate 20.

As long as the light transmissive substrate realizes the characteristic of refracting the incident light incident on the mesa structure region from the back surface side toward the center side of the mesa structure region, the mesa structure is as shown in FIG. A transfer pattern may be provided on the surface of the mesa structure, or a transfer pattern may not be provided on the surface of the mesa structure as shown in FIG.

d. Others The shape of the light transmissive substrate is not particularly limited, but is usually rectangular. In this case, the length and width of the light transmissive substrate vary depending on the application and the like, but are, for example, about 142 mm to 162 mm. The thickness of the light-transmitting substrate varies depending on the material, application, and the like, but is, for example, about 0.5 mm to 15 mm.

Examples of the material constituting the light transmissive substrate include synthetic quartz, soda glass, fluorite, calcium fluoride and the like. Among them, synthetic quartz is preferably used because it has a high track record of use in imprint mold forming substrates, its quality is stable, and it is possible to form a fine transfer pattern with high precision. As for the light transmittance of the light-transmitting substrate, it is preferable that the light transmittance in the wavelength range of 300 nm to 450 nm is 85% or more.

2. Others (1) Light-shielding film The imprint mold of the first embodiment may include a light-shielding film.

5 (a) to 5 (c) are schematic cross-sectional views showing other examples of the imprint mold of the first embodiment, respectively, and show a cross section corresponding to the cross section shown in FIG. 1 (b). Is.

In the imprint mold 10 shown in FIG. 5A, a light-shielding film 40a is provided around the mesa structure 22 on the surface 20a of the light-transmitting substrate 20. Further, in the imprint mold 10 shown in FIG. 5B, a light-shielding film 40b is provided on the side surface 22b of the mesa structure 22. Further, in the imprint mold 10 shown in FIG. 5C, a light-shielding film 40c is provided around the mesa structure region M on the back surface 26b inside the recess 26 of the light transmissive substrate 20.

As the imprint mold, as shown in FIG. 5A, it is preferable that a light-shielding film is provided around the mesa structure on the surface of the light-transmitting substrate. This is because it is possible to prevent the exposure light from being transmitted from the periphery of the mesa structure, so that it is possible to effectively suppress the curing of the curable resin that has exuded to the outside.

Further, as the imprint mold, as shown in FIG. 5B, in addition to the light-shielding film on the surface, a light-shielding film may be further provided on the side surface of the mesa structure. The light-shielding film can also prevent the exposure light from being transmitted from the side surface of the mesa structure. Even when a defect is formed in the light-shielding film, it is possible to prevent the exposure light from being transmitted from the side surface of the mesa structure through the defect by refracting the exposure light by the convex lens-shaped portion.

Further, as the imprint mold, as shown in FIG. 5C, a light-shielding film may be provided around the mesa structure region on the back surface of the light-transmitting substrate. This is because it is possible to prevent the exposure light from being transmitted from the periphery of the mesa structure region, so that it is possible to effectively suppress the curing of the curable resin that has exuded to the outside. ..

Examples of the material constituting the light-shielding film include metals such as aluminum, nickel, cobalt, chromium, titanium, tantalum, tungsten, molybdenum, tin and zinc, silicon and the like, and oxides thereof. Nitride, alloy and the like can also be used. As for the light-shielding property of the light-shielding film, the transmittance of light rays in the wavelength range of 300 nm to 450 nm is preferably 1% or less, and more preferably 0.1% or less.

Examples of the method for forming the light-shielding film include a PVD method (physical vapor deposition) such as a vacuum vapor deposition method, a sputtering method, and an ion plating method, a plasma CVD method, a thermal CVD method, and a CVD method such as an optical CVD method. Chemical vapor deposition) and the like, as well as the application of paints, dyes, pigments and the like.

(2) Manufacturing Method The manufacturing method of the imprint mold of the first embodiment is not particularly limited, and for example, a general manufacturing method from a general imprint mold forming blank provided with a light-transmitting substrate. Can be manufactured by using.

(3) Others As the imprint mold of the present invention, the first embodiment is easier to manufacture than the second embodiment described later.

II. 2nd Embodiment In the imprint mold of the 2nd embodiment, in the mesa structure region of the light transmissive substrate, a refractive index changing portion in which the refractive index continuously increases toward the center side of the mesa structure region is provided. It is characterized in that it is provided.

An example of the imprint mold of the second embodiment will be described with reference to the drawings. FIG. 6A is a schematic plan view showing an example of the imprint mold of the second embodiment. FIG. 6B is a cross-sectional view taken along the line AA shown in FIG. 6A. FIG. 6A is a plan view from the back surface 20b side of the light transmissive substrate 20 shown in FIG. 6B.

As shown in FIGS. 6A and 6B, the imprint mold 10 is provided with the mesa structure 22, the transfer pattern 24, and the recess 26 in the same manner as the imprint mold 10 shown in FIG. A light transmissive substrate 20 is provided.

In the light-transmitting substrate 20, inside the peripheral portion M _{P (portion} sandwiched between dashed lines indicate the outer periphery of the mesa structure region M and its inner dashed line) and an outer peripheral portion M _P of the mesa structure region M in plan view and in a region including the outer region, the refractive index change portion N _C the refractive index towards the center of the mesa structure region M is continuously increased is provided. Further, on the outside of the refractive index change portion N _C, a lower refractive index than the other regions the low refractive index portion N _L is provided. Further, the center of the refractive index change portion N _C, refractive index is higher than other regions high refractive index portions N _H is provided. Therefore, it becomes possible to light incident from the rear surface 20b side of the light-transmitting substrate 20 on the mesa structure region M is incident on the refractive index change portion N _C, the mesa structure incident light incident on the refractive index change portion N _C It can be refracted toward the center of the region M. Specifically, incident light by utilizing the property of refracted from low to high refractive index, the refractive index change portion N _C in which the refractive index is continuously increased toward the center of the mesa structure region M The incident light can be refracted toward the center of the mesa structure region M. In particular, the refractive index change portion N _C is provided in a region including the outer peripheral portion M _P of the mesa structure region M, the center side of the mesa structure region M of the light incident to the outer peripheral portion M _P of the mesa structure region M Can be refracted into.

Therefore, in the exposure process shown in FIG. 19 (c) and FIG. 20 to be described later, the imprint mold 10 instead, the refractive index change portion N _C is provided in the imprint mold 10 which convex lens portion 28 is provided in the case of using, because the exposure light is made incident on the refractive index change portion N _C, it can refract the exposure light toward the center of the mesa structure region M. Thereby, the same action and effect as those of the first embodiment can be obtained.

1. 1. Light-transparent substrate The light-transparent substrate is provided with a refractive index changing portion in the mesa structure region in which the refractive index continuously increases toward the center side of the mesa structure region.

(1) Refractive index change portion The refractive index change portion is a part of the light transmissive substrate provided in the mesa structure region and whose refractive index continuously increases toward the center side of the mesa structure region. ..

Here, the mesa structure region in the second embodiment is, for example, the mesa structure region M shown in FIG. 6, and means a region similar to the mesa structure region in the first embodiment.

The refractive index changing portion realizes a characteristic of refracting incident light incident on the mesa structure region from the back surface side toward the center side of the mesa structure region, and is provided in a region including a part or the whole of the mesa structure region. However, as shown in FIG. 6, those provided in the region including the outer peripheral portion of the mesa structure region are preferable. By refracting the incident light incident on the outer peripheral portion of the mesa structure region toward the center side of the mesa structure region, it is possible to effectively prevent the exposure light from being transmitted from the side surface of the mesa structure region. be.

Here, the outer peripheral portion of the mesa structure region in the second embodiment, for example, an outer peripheral portion M _P shown in FIG. 6, refer to like parts and the outer peripheral portion of the mesa structure region in the first embodiment do. Since the width of the outer peripheral portion of the mesa structure region is the same as that of the first embodiment, the description here is omitted.

FIG. 7 is a schematic cross-sectional view showing another example of the imprint mold of the second embodiment, and shows a cross section corresponding to the cross section shown in FIG. 6 (b).

Imprint mold 10 shown in FIG. 7, in that the refractive index change portion N _C is provided only on the outer peripheral portion M _P of the mesa structure region M, is different from the imprint mold 10 shown in FIG. 6 ..

As the refractive index changing portion, as shown in FIG. 7, the above-mentioned mesa structure region in the region inside the recess described in the item of “(3) Light-transmitting substrate c. Recess” described later. Those provided only on the outer peripheral portion are preferable. The region inside the outer peripheral portion of the mesa structure region can be composed of a single material. As a result, when the transfer pattern of the imprint mold is brought into close contact with the curable resin layer applied to the surface of the object to be transferred, the air pressure in the recess is increased to bend the imprint mold, thereby forming the transfer pattern. In the case of suppressing the encapsulation of air between the curable resin layer and the curable resin layer, by forming the inner region of the outer peripheral portion with a single material, the transfer pattern region of the imprint mold can be flexed. Can be constant. Therefore, it becomes easy to predict the dimensional variation of the transfer pattern region, and it becomes easy to correct the dimension of the transfer pattern region that cancels the dimensional variation.

As shown in FIG. 6, the refractive index changing portion may be provided in a region including an inner or outer region of the outer peripheral portion of the mesa structure region in the light transmissive substrate.

Further, as the refractive index changing portion, the refractive index is continuous toward the center side so as to realize the characteristic of refracting the incident light incident on the mesa structure region from the back surface side toward the center side of the mesa structure region. It is not particularly limited as long as it is a part of the above-mentioned substrate, but the refractive index at the position adjacent to the low refractive index portion (lowest refractive index) and the refraction at the position adjacent to the high refractive index portion described later are not particularly limited. The difference in rate (highest refractive index) is preferably in the range of 0.2 to 0.6, and more preferably in the range of 0.3 to 0.5. This is because the incident light can be effectively refracted.

Further, as indicated by W _C in FIG. 6, the width direction of the refractive index change portion in which the refractive index changes, the center side of the mesa structure region light incident from the back side mesa structure region The width is not particularly limited as long as it can realize the characteristic of refracting to, but it is preferably in the range of 1 μm to 5 mm, and more preferably in the range of 50 μm to 1 mm. If it is too small, the change in the refractive index is too rapid to effectively refract the incident light, and if it is too large, the change in the refractive index is too slow to effectively refract the incident light. Because it cannot be done.

(2) Low Refractive Index and High Refractive Index The light transmissive substrate is usually provided with a low refractive index portion outside the refractive index change portion as shown in FIG. 6, and the refractive index change. A high refractive index portion is provided on the central side of the portion, and the refractive index changing portion is provided between the low refractive index portion and the high refractive index portion.

a. Low refractive index portion The low refractive index portion is provided outside the refractive index changing portion in the light transmissive substrate.

The refractive index of the low refractive index portion is not particularly limited as long as it is lower than that of the high refractive index portion, but is preferably in the range of 1.3 to 1.5. This is because the incident light can be effectively refracted.

Since the material constituting the low refractive index portion is the same as the material constituting the light transmissive substrate in the first embodiment, the description here is omitted. Further, since the light transmission of the low refractive index portion is the same as the light transmission of the light transmitting substrate in the first embodiment, the description here is omitted.

b. High-refractive index portion The high-refractive index portion is provided on the central side of the mesa structure region with respect to the refractive index changing portion in the light-transmitting substrate.

The refractive index of the high refractive index portion is not particularly limited as long as it is higher than that of the low refractive index portion, but is preferably in the range of 1.4 to 2.2, and in particular, in the range of 1.65 to 1.85. It is preferably inside. This is because the incident light can be effectively refracted.

The material constituting the high refractive index portion is not particularly limited as long as it can have a higher refractive index than the low refractive index portion, but for example, SiO ₂ , B ₂ O ₃ , P ₂ O ₅ , TiO ₂ , etc. Examples thereof include glass containing _{Nb 2} O ₅ , La ₂ O ₃ , Y ₂ O ₃ , Gd ₂ O _{3, and the like.} Of these, _{glass containing TiO 2} , Nb ₂ O _{5, and the} like is preferable. This is because a high refractive index material having good properties is easily available. As for the light transmittance of the high refractive index portion, it is preferable that the transmittance of light rays in the wavelength range of 300 nm to 450 nm is 85% or more.

The shape and size of the high refractive index portion can be appropriately selected according to the shape and size of the refractive index changing portion.

(3) Light transmissive substrate a. Contact portions FIGS. 8 (a) to 8 (c) are schematic cross-sectional views showing another example of the imprint mold of the second embodiment, and the cross sections corresponding to the cross sections shown in FIG. 6 (b) are respectively. It shows.

Light transmitting substrate 20 in the imprint mold 10 shown in FIG. 8 (a), and the substrate section 20n which refractive index change portion N _C and the low refractive index portion N _L and the high refractive index portions N _H is provided, the substrate portion 20n of the surface side of the mesa structure contact portion provided on a surface of the mesa base portion 22n provided in the region M 20s (thickness _H S: _2μm~50μm) and has a light transmissive substrate 20 The mesa structure 22 (thickness: 10 μm to 50 μm) includes a mesa base portion 22n and a contact portion 20s. A transfer pattern 24 is provided on the surface 22a of the contact portion 22s.

Light transmitting substrate 20 in the imprint mold 10 shown in FIG. 8 (b), and the substrate section 20n which refractive index change portion N _C and the low refractive index portion N _L and the high refractive index portions N _H is provided, the substrate portion 20n contact portion 20s (thickness _H S: 10 m to 50 m) provided on the mesa structure region M of the surface of the has a mesa structure 22 of the light-transmitting substrate 20 (thickness: 10 m to 50 m) is , Only the entire contact portion 20s is included. A transfer pattern 24 is provided on the surface 22a of the mesa structure 22.

Light transmitting substrate 20 in the imprint mold 10 shown in FIG. 8 (c), and the substrate section 20n which refractive index change portion N _C and the low refractive index portion N _L and the high refractive index portions N _H is provided, the substrate portion 20n contact portion 20s (thickness _H S: 10 m - 100 m) which is provided on the entire surface of the has a light transmissive substrate 20 mesa structure 22 (thickness: 10 m to 50 m) is, the contact portion It is provided in the mesa structure region M on the surface 20a side of 20s. A transfer pattern 24 is provided on the surface 22a of the mesa structure 22.

The light transmissive substrate may include a single member or a plurality of members, but as shown in FIGS. 8 (a) to 8 (c), the substrate portion and the above. Those having a contact portion provided on the surface of the substrate portion are preferable. For example, when it becomes difficult to process the substrate portion due to the provision of the refractive index changing portion and the high refractive index, a material that is easier to process than the substrate portion can be used for the contact portion. For example, it becomes easy to form a transfer pattern on the surface of the mesa structure.

The material constituting the contact portion is preferably one that is easier to process than the substrate portion. Examples of such a material include the same material as the light transmissive substrate in the first embodiment. Further, since the light transmissivity of the contact portion is the same as that of the light transmissive substrate in the first embodiment, the description here is omitted.

Figure 8 (a) thickness of the contact portion as shown by _{H S} in to FIG. 8 (c), but is different in accordance with the application etc., for example in the range of 2Myuemu～100myuemu.

b. Mesa structure The shape and height of the mesa structure in a plan view and the vertical and horizontal lengths of the rectangular mesa structure in a plan view are the same as those of the mesa structure in the first embodiment. Is omitted.

Since the method for forming the mesa structure is the same as that of the first embodiment, the description here is omitted.

c. Recessed FIG. 9 is a schematic cross-sectional view showing another example of the imprint mold of the second embodiment, and shows a cross section corresponding to the cross section shown in FIG. 6 (b).

In imprint mold 10 shown in FIG. 9, the light-transmitting substrate 20 a recess 26 is not provided as shown in FIG. 6, a region including the outer peripheral portion M _P of the mesa structure region M in plan view, Mesa refractive index towards the center side of the structural region M is continuously high and the high refractive index portion N _H is provided on the outside of the refractive index change portion N _C low refractive index portion N _L is provided, the refractive the center side of the rate change unit N _C high refractive index portion N _H is provided.

As the light transmissive substrate, as shown in FIGS. 6 to 8, the region including the mesa structure region on the back surface side may be provided with the recess, as shown in FIG. Although the recess may not be provided in the above, it is preferable that the recess is provided. When the transfer pattern of the imprint mold is brought into close contact with the curable resin layer applied to the surface of the transferred body, the transfer pattern and the curable resin layer are formed by increasing the air pressure in the recess to bend the imprint mold. This is because it is possible to prevent air from being sealed between the two.

Since the recess is the same as the recess in the first embodiment, the description thereof is omitted here.

d. Transfer Patterns FIGS. 10 (a) and 10 (b) are schematic cross-sectional views showing another example of the imprint mold of the second embodiment, respectively, and show a cross section corresponding to the cross section shown in FIG. 6 (b). It shows.

The imprint mold 10 shown in FIG. 10A is different from the imprint mold 10 shown in FIG. 6 in that a transfer pattern is not provided on the surface of the mesa structure 22 of the light transmissive substrate 20. .. Further, the imprint mold 10 shown in FIG. 10B is an imprint mold shown in FIG. 8 in that a transfer pattern is not provided on the surface of the contact portion 22s in the mesa structure 22 of the light transmissive substrate 20. It is different from 10.

As the light transmissive substrate, if it realizes the characteristic of refracting the incident light incident on the mesa structure region from the back surface side toward the center side of the mesa structure region, as shown in FIGS. 6 and 8. A transfer pattern may be provided on the surface of the mesa structure, or a transfer pattern may not be provided on the surface of the mesa structure as shown in FIGS. 10 (a) and 10 (b). ..

e. Others The shape of the light-transmitting substrate is the same as the shape of the light-transmitting substrate in the first embodiment, and thus the description thereof is omitted here. Further, since the thickness of the light-transmitting substrate is the same as the thickness of the light-transmitting substrate in the first embodiment, the description here is omitted.

2. Others (1) Light-shielding film The imprint mold of the second embodiment may include a light-shielding film.

11 (a) to 11 (c) are schematic cross-sectional views showing other examples of the imprint mold of the second embodiment, respectively, and show a cross section corresponding to the cross section shown in FIG. 6 (b). Is.

In the imprint mold 10 shown in FIG. 11A, a light-shielding film 40a is provided around the mesa structure 22 on the surface 20a of the light-transmitting substrate 20. Further, in the imprint mold 10 shown in FIG. 11B, a light-shielding film 40b is provided on the side surface 22b of the mesa structure 22. Further, in the imprint mold 10 shown in FIG. 11C, a light-shielding film 40c is provided around the mesa structure region M on the back surface 26b inside the recess 26 of the light transmissive substrate 20.

As the imprint mold, for the same reason as in the first embodiment, as shown in FIG. 11A, a light-shielding film is provided around the mesa structure on the surface of the light-transmitting substrate. Is preferable. Further, as in the first embodiment, as shown in FIG. 11B, in addition to the light-shielding film on the surface, a light-shielding film may be further provided on the side surface of the mesa structure. Further, for the same reason as in the first embodiment, as shown in FIG. 11C, a light-shielding film is provided around the mesa structure region on the back surface of the light-transmitting substrate. May be good.

Since the method for forming the light-shielding film is the same as that of the first embodiment, the description here is omitted.

(2) Manufacturing Method The manufacturing method of the imprint mold is not particularly limited, but is usually for imprint mold forming described in the item of "B. Imprint mold forming blank" described later. The method of manufacturing the above-mentioned imprint mold from a blank is used.

In this method, the imprint mold can be manufactured by preparing the blank for forming the imprint mold and forming the mesa structure in the mesa structure region on the surface side of the light transmissive substrate in the blank. can.

Here, FIGS. 12 (a) to 12 (b) are schematic process cross-sectional views showing an example of a method for manufacturing an imprint mold forming blank according to the second embodiment. 13 (a) to 13 (b), 14 (a) to 14 (b), and 15 (a) to 15 (b) are for forming the imprint mold of the second embodiment. It is a schematic process sectional view which shows each other example of the manufacturing method of a blank.

Figure In the example shown in 12, first, as shown in FIG. 12 (a), only the substrate part 20n which refractive index change portion N _C and the low refractive index portion N _L and the high refractive index portions N _H is provided A blank 50 for forming an imprint mold, which comprises the light transmissive substrate 20 to be provided, is prepared. Next, as shown in FIG. 12B, the light transmissive substrate 20 is wet-etched from the surface 20a side to form a mesa structure 22 (height: 10 μm to 50 μm) in the mesa structure region M. As a result, in the imprint mold 10 shown in FIG. 6, the imprint mold 10 before the recess 26 and the transfer pattern 24 are provided can be manufactured.

In the example shown in FIG. 13, first, as a substrate portion 20n which refractive index change portion N _C and the low refractive index portion N _L and the high refractive index portions N _H is provided as shown in FIG. 13 (a), An imprint mold forming blank 50 including a light-transmitting substrate 20 having a contact portion 20s (thickness: 2 μm to 50 μm) provided on the entire surface of the substrate portion 20n is prepared. Next, as shown in FIG. 13B, both the contact portion 20s and the substrate portion 20n are wet-etched from the surface 20a side of the light transmissive substrate 20, and the mesa structure 22 (height) is formed in the mesa structure region M. : 10 μm to 50 μm) is formed. As a result, in the imprint mold 10 shown in FIG. 8A, the imprint mold 10 before the recess 26 and the transfer pattern 24 are provided can be manufactured.

In the example shown in FIG. 14, first, as shown in FIG. 14 (a), only the refractive index change portion N _C and the substrate portion 20n of the low refractive index portion N _L and the high refractive index portions N _H is provided A blank 50 for forming an imprint mold, which comprises the light transmissive substrate 20 to be provided, is prepared. Next, as shown in FIG. 14B, a contact portion 20s (height: 10 μm to 50 μm) is formed as the mesa structure 22 in the mesa structure region M on the surface of the substrate portion 20n. As a result, in the imprint mold 10 shown in FIG. 8B, the imprint mold 10 before the recess 26 and the transfer pattern 24 are provided can be manufactured.

In the example shown in FIG. 15, first, as a substrate portion 20n which refractive index change portion N _C and the low refractive index portion N _L and the high refractive index portions N _H is provided as shown in FIG. 15 (a), An imprint mold forming blank 50 including a light-transmitting substrate 20 having a contact portion 20s (thickness: 10 μm to 100 μm) provided on the entire surface of the substrate portion 20n is prepared. Next, as shown in FIG. 15B, only the contact portion 20s is wet-etched from the surface 20a side of the light transmissive substrate 20, and the mesa structure 22 (height: 10 μm to 50 μm) is formed in the mesa structure region M. To form. As a result, in the imprint mold 10 shown in FIG. 8C, the imprint mold 10 before the recess 26 and the transfer pattern 24 are provided can be manufactured.

(3) Others The imprint mold of the present invention may be a combination of both the first embodiment and the second embodiment.

III. Other Embodiments The imprint mold of the present invention is not limited to the first embodiment, the second embodiment, and a combination thereof as long as it realizes the above-mentioned property of refracting incident light. For example, other embodiments as shown in FIG. 16 below may be used.

FIG. 16 is a schematic cross-sectional view showing an example of an imprint mold according to another embodiment of the present invention, and shows a cross section corresponding to the cross section shown in FIG. 6 (b).

The imprint mold 10 shown in FIG. 16 includes a light transmissive substrate 20 provided with a mesa structure 22, a transfer pattern 24, and a recess 26, similarly to the imprint mold 10 shown in FIG.

In the light-transmitting substrate 20, in plan view in a region including the outer peripheral portion M _P of the mesa structure region M (portion sandwiched between the dashed lines indicate the outer periphery of the mesa structure region M and its inner dashed line), the mesa structure refractive index toward the surface 22a side of 22 the refractive index change portion N _C which continuously increases is provided. Further, the low refractive index portion N _L is provided on the rear surface 26b side of the refractive index change portion N _C. Further, also, the high refractive index portion N _H is provided on the surface 22a side of the refractive index change portion N _C. Therefore, it becomes possible to light incident from the rear surface 20b side of the light-transmitting substrate 20 on the mesa structure region M is incident on the refractive index change portion N _C, to refract the incident light on the surface 22a side of the mesa structure 22 be able to. In particular, it is possible to refract light incident to the outer peripheral portion M _P of the mesa structure region M on the surface 22a side of the mesa structure 22. Therefore, the same effect as that of the first embodiment and the second embodiment can be obtained.

B. Imprint mold forming blank The imprint mold forming blank of the present invention is a member used for the imprint mold described in the above-mentioned item "A. Imprint mold II. Second embodiment", and is described above. In the region of the imprint mold forming blank that becomes the mesa structure region, a refractive index changing portion in which the refraction coefficient continuously increases toward the center side of the region that becomes the mesa structure region is provided. It is characterized by being. Specifically, a light-transmitting substrate having a front surface and a back surface is provided, and a refractive index changing portion in which the refractive index continuously increases toward the center side is provided in a region of the light-transmitting substrate which is the mesa structure region. It is characterized by being.

An example of the blank for forming an imprint mold of the present invention will be described with reference to the drawings. FIG. 17A is a schematic plan view showing an example of a blank for forming an imprint mold of the present invention. FIG. 17B is a cross-sectional view taken along the line AA shown in FIG. 17A. FIG. 17A is a plan view from the back surface 20b side of the light transmissive substrate 20 shown in FIG. 17B.

As shown in FIGS. 17A and 17B, the imprint mold forming blank 50 includes a light transmissive substrate 20 having a front surface 20a and a back surface 20b.

In the light-transmitting substrate 20, inside the peripheral portion M _{P (portion} sandwiched between dashed lines indicate the outer periphery of the mesa structure region M and its inner dashed line) and an outer peripheral portion M _P of the mesa structure region M in plan view and in a region including the outer region, the refractive index change portion N _C the refractive index towards the center of the mesa structure region M is continuously increased is provided. Further, on the outside of the refractive index change portion N _C, a lower refractive index than the other regions the low refractive index portion N _L is provided. Further, the center of the refractive index change portion N _C, refractive index is higher than other regions high refractive index portions N _H is provided. As a result, the imprint mold 10 shown in FIG. 6 can be manufactured from the imprint mold forming blank 50.

Therefore, according to the present invention, by preventing the exposure light from being transmitted from the side surface of the mesa structure, the curable resin exuded to the outside of the region of one pattern on the surface of the transferred body is exposed. It is possible to manufacture an imprint mold that can sufficiently suppress this.

1. 1. Light-transparent substrate The light-transparent substrate has a front surface and a back surface, and a refractive index changing portion in which the refractive index continuously increases toward the center side is provided in a region to be the mesa structure region in the imprint mold. It is what has been done.

The light transmissive substrate is provided with the light transmissive substrate in the imprint mold of the second embodiment described in the item of "A. Imprint mold II. Second embodiment" described above and the mesa structure described above. Since it is the same except that it is not specified, the description here is omitted.

2. Manufacturing Method The manufacturing method of the blank for forming an imprint mold is not particularly limited, but for example, a fitting hole forming step of forming a fitting hole in a low refractive index substrate and a high refractive index substrate in the fitting hole. Examples thereof include a method including a fitting step of fitting and a fusion step of fusing the low refractive index substrate and the high refractive index substrate fitted in the fitting hole by heating.

An example of the method for producing a blank for forming an imprint mold of the present invention will be described with reference to the drawings. 18 (a) to 18 (f) are schematic process cross-sectional views showing an example of the method for manufacturing an imprint mold forming blank of the present invention. Each cross-sectional view shows a cross section corresponding to the cross section shown in FIG. 17 (b).

First, as shown in FIG. 18A, the low refractive index substrate 34 is prepared. Next, as shown in FIG. 18B, the fitting hole 36 is formed by drilling the central portion of the low refractive index substrate 34 in a plan view.

Next, as shown in FIGS. 18 (c) and 18 (d), a high refractive index substrate 38 having a refractive index higher than that of the low refractive index substrate 34 is prepared and fitted into the fitting hole 36.

Next, as shown in FIG. 18E, the low refractive index substrate 34 in which the high refractive index substrate 38 is fitted is heated for a predetermined time to fuse the high refractive index substrate 38 and the low refractive index substrate 34. .. At this time, the substrate components are diffused to each other at the boundary between the high refractive index substrate 38 and the light transmissive substrate 2. Thus, the region including the outer peripheral portion M _P of the mesa structure region M _(portion sandwiched between the dashed lines indicate the outer periphery of the mesa structure region M and its inner dashed line), a continuous refractive index toward the center forming a becomes higher refractive index change portion N _C on. Then, on the outside of the refractive index change portion N _C, to form a low refractive index portion N _L has a lower refractive index than the other regions, the center of the refractive index change portion N _C, a high refractive index is higher than in other regions The refractive index portion _NH is formed.

Next, as shown in FIG. 18 (f), the front surface 20a and the back surface 20b of the fused substrate 20 are flattened by polishing with the polishing apparatus 60 including the fused portion. As a result, the imprint mold forming blank 50 shown in FIG. 17 can be manufactured.

C. Method for manufacturing a pattern transfer body In the method for manufacturing a pattern transfer body of the present invention, a transfer pattern of a mold provided with a transfer pattern among the imprint molds described in the above-mentioned item "A. Imprint mold" is used. It is characterized by having a transfer step of transferring to a curable resin layer provided on the surface of the transferred body.

An example of the method for producing the pattern transfer product of the present invention will be described with reference to the drawings. 19 (a) to 19 (d) are schematic process cross-sectional views showing an example of the method for producing the pattern transfer body of the present invention. Each cross-sectional view shows a cross section corresponding to the cross section shown in FIG. 1 (b).

First, as shown in FIG. 19A, the curable resin layer 2 is applied to the surface 1a of the transferred body 1, and the imprint mold 10 is prepared. The imprint mold 10 is the same as the imprint mold 10 shown in FIG.

Next, as shown in FIG. 19B, the imprint mold 10 is brought into close contact with the curable resin layer 2 so that the transfer pattern 24 provided on the surface 22a of the mesa structure 22 is in contact with the curable resin layer 2. At this time, on the surface 1a of the transferred body 1, a part of the curable resin 2b may be extruded by the mesa structure 22 and seep out of the region of one pattern.

Next, as shown in FIG. 19C, the curable resin layer 2 is formed by injecting the exposure light into the mesa structure region M from the back surface 20b side of the light transmissive substrate 20 in a state where the two are in close contact with each other. To cure. At this time, since the exposure light is incident on the convex lens shape portion 28, the exposure light can be refracted toward the center side of the mesa structure region M. As a result, as shown in FIG. 20, which is an enlarged view of the region A shown in FIG. 19 (c), it is possible to prevent the scattered exposure light from being transmitted from the side surface 22b of the mesa structure 22. In particular, since the exposure light incident to the outer peripheral portion M _P of the mesa structure region M can be refracted toward the center of the mesa structure region M, preventing the transmission of exposure light from the side surface 22b of the mesa structure 22 effectively Can be done. As shown in FIG. 22 described above, even when the defect 42 is formed on the light-shielding film 40b provided on the side surface 22b of the mesa structure 22, the scattered exposure light is transmitted from the side surface 22b of the mesa structure 22 through the defect 42. It is possible to prevent transmission. Therefore, even if the light-shielding film 40b is not provided on the side surface 22b of the mesa structure 22, or even if the defect 42 is formed on the light-shielding film 40b, the surface 1a of the transferred body 1 is outside the region for one pattern. It is possible to sufficiently prevent the curable resin 2b that has exuded into the surface from being exposed and cured.

Next, as shown in FIG. 19D, the imprint mold 10 is peeled off from the resin layer, and the curable resin exuded to the outside of the region of one pattern on the surface 1a of the transferred body 1. Remove 2b. As a result, the transfer pattern 24 is transferred to form a cured resin layer 2'.

Next, although not shown, the concave portion of the pattern of the resin layer 2'is etched until the surface 1a of the transferred body 1 is exposed, and then the exposed portion of the surface 1a of the transferred body 1 is etched. Next, the resin layer 2'is removed. As a result, a pattern transfer body in which the transfer pattern 24 is transferred to the transfer target body 1 is manufactured.

Therefore, according to the present invention, by preventing the exposure light from being transmitted from the side surface of the mesa structure, the curable resin exuded to the outside of the region of one pattern on the surface of the transferred body is exposed. It can be sufficiently suppressed.

1. 1. Transfer Step In the transfer step, the transfer pattern of the imprint mold is transferred to a curable resin layer provided on the surface of the transferred body.

The imprint mold may be any of the imprint molds described in the above-mentioned item "A. Imprint mold" as long as the transfer pattern is provided.

In the transfer step, usually, in order to transfer a plurality of patterns to the transfer target, a curable resin layer is applied to the regions of the plurality of patterns on the surface of the transfer target and the curable resin is applied. A step-and-repeat method is used in which the transfer pattern of the imprint mold is transferred to the layer a plurality of times in succession. In this case, by using the imprint mold, it is possible to sufficiently prevent the curable resin that has exuded to the outside of the region for one pattern from being cured, so that one pattern can be used. It is possible to avoid difficulty in transferring to the region of another adjacent pattern following the transfer to the region of. In addition, when the resin that has exuded to the outside is cured in a raised shape, the imprint mold may be damaged by contact with the cured resin, or particles may be generated due to the cured resin. It can be avoided.

2. Others In the method for producing a pattern transfer body of the present invention, when the curable resin layer is applied to the surface of the transfer body, it is applied only to the portion facing the transfer pattern as shown in FIG. 19 (a). Instead, it may be applied to the entire surface of the transferred body. Further, as shown in FIG. 19A, the coating may be applied not to the entire portion of the surface of the transferred body facing the transfer pattern, but to a part of the portion. In this case, in the step corresponding to the step of FIG. 19B in which the imprint mold is brought into close contact with the curable resin layer so that the transfer pattern is in contact with the curable resin layer, the surface of the mesa structure forms the curable resin layer. By pushing and expanding, it can be expanded over the entire portion facing the transfer pattern.

The method for producing the pattern transfer body of the present invention is not particularly limited as long as it has the above transfer step, but usually, the recess of the pattern of the resin layer to which the transfer pattern is transferred and cured is formed in the recess of the pattern to be transferred. It further includes a step of etching the exposed portion of the surface of the transferred body after etching until the surface is exposed, and a step of removing the cured resin layer. A pattern transfer body in which the transfer pattern is transferred to the transfer target body can be produced.

The present invention is not limited to the above embodiment. The above embodiment is an example, and any one having substantially the same configuration as the technical idea described in the claims of the present invention and exhibiting the same effect and effect is the present invention. It is included in the technical scope of the invention.

10 ... Imprint mold 20 ... Light transmissive substrate 22 ... Mesa structure 28 ... Convex lens shape part Nc ... Refractive index change part

Claims (8)

With a light transmissive substrate with front and back surfaces
A mesa structure is provided on the surface side of the light transmissive substrate.
The mesa structure region, which is a region that coincides with the region where the mesa structure is provided in a plan view, has a characteristic of refracting incident light incident from the back surface side of the light transmissive substrate toward the center side of the mesa structure region. have a,
An imprint mold characterized in that the mesa structure region of the light transmissive substrate is provided with a refractive index changing portion in which the refractive index continuously increases toward the center side of the mesa structure region. The imprint mold according to claim 1 , wherein the refractive index changing portion is provided in a region including an outer peripheral portion of the mesa structure region. The imprint mold according to claim 1 or 2, wherein a recess is provided in a region including the mesa structure region on the back surface side of the light transmissive substrate. The imprint mold according to any one of claims 1 to 3 , wherein a light-shielding film is provided around the mesa structure on the surface of the light-transmitting substrate. The imprint mold according to any one of claims 1 to 3 , wherein a light-shielding film is provided around the mesa structure region on the back surface of the light-transmitting substrate. The imprint mold according to any one of claims 1 to 5, wherein a transfer pattern is provided on the surface of the mesa structure. A blank for forming an imprint mold used in the imprint mold according to claim 1 or 2.
The region of the imprint mold forming blank that becomes the mesa structure region is provided with a refractive index changing portion in which the refractive index continuously increases toward the center side of the region that becomes the mesa structure region. A blank for forming an imprint mold, which is characterized by being used. A method for producing a pattern transfer body, which comprises a transfer step of transferring the transfer pattern of the imprint mold according to claim 6 to a curable resin layer provided on the surface of the transfer body.

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