JP6864443B2 - Alignment method, imprint method and imprint device - Google Patents

Description

The present invention relates to a method of aligning a substrate and a mold, an imprint method, and an imprint apparatus.

In recent years, the development of a microfabrication technique for transferring a fine uneven pattern on a mold to a substrate made of a semiconductor, glass, resin, metal or the like has been further advanced.
In particular, nanoimprint is a technology that can realize ultra-fine processing with a concavo-convex pattern width of several nanometers (2 nm to 1000 nm) by pressing a mold on which a nano-sized fine concavo-convex pattern is formed against a substrate. Therefore, nanoimprint is expected to be applied to a wide range of fields such as semiconductor devices, optical elements, and biochips because of its three advantages of high resolution, excellent dimensional controllability, and low cost.

Among various nanoimprint methods, the case where the optical nanoimprint method is used for semiconductor device manufacturing will be described below.
First, an ultraviolet curable resin composition is applied onto a substrate (for example, a semiconductor wafer such as a silicon wafer) to form a photocurable resin layer. Next, a transparent mold having a desired uneven structure formed in the transfer region and having a release-treated layer on the surface is pressed against the photocurable resin layer. Further, by irradiating with ultraviolet rays, the photocurable resin layer is cured to form a cured resin layer made of a cured resin. As a result, the uneven structure of the mold in the transfer region is transferred to the cured resin layer. After the mold is released, the uneven structure is transferred to the substrate by etching or the like using the cured resin layer as a mask.

In such an imprint method, since it is necessary to form a plurality of layers having a fine uneven pattern on the substrate by using a plurality of molds, the concave-convex structure of the mold is transferred to the photocurable resin layer on the substrate. Sometimes it is necessary to align the mold and the substrate with high accuracy. Therefore, in general, the mold-side alignment mark provided on the mold side and the substrate-side alignment mark provided on the substrate side are formed with the photocurable resin layer sandwiched between the mold and the substrate. The misalignment between the two alignment marks is obtained by optically detecting from the mold side, and the alignment is performed by correcting the relative positions of the two.

In the method in which the mold and the substrate are aligned in a separated state and then the mold is brought into contact with the photocurable resin layer applied on the substrate, the position is displaced in the process of bringing the mold into contact with the photocurable resin layer on the substrate. Is likely to occur. Therefore, in the above-mentioned alignment method, it has been proposed to perform alignment in a state where the mold is in contact with the photocurable resin layer on the substrate.
However, when the mold side alignment mark is filled with the ultraviolet curable resin composition, if there is no significant difference between the refractive index of the mold material and the refractive index of the ultraviolet curable resin composition, the mold side alignment mark is optically used. There is a problem that it becomes difficult to identify the target.

To solve this problem, a method for distinguishing between the mold-side alignment mark and the substrate-side alignment mark has been proposed.
For example, by setting the refractive index of the curable resin before curing to 1.7 or more, the refractive index is significantly different from the refractive index of the mold material (about 1.45 for a glass mold), and the alignment mark on the mold side is identified. A method has been proposed (Patent Document 1).
In the invention described in Patent Document 1, when the step between the concave portion and the convex portion of the mold-side alignment mark is set to 150 nm, a reciprocating optical path length difference of 75 nm or more can be obtained by the configuration. Since this round-trip optical path length difference corresponds to about 1/8 of the wavelength of 633 nm, it is said that the mold-side alignment mark can be sufficiently identified by observation with an optical microscope using a light source having a wavelength of 633 nm. Specifically, as a method for obtaining a photocurable resin having a refractive index of 1.7 or more, a method of dispersing and mixing a titanium oxide having a refractive index of 2.4 in fine particles into a conventional photocurable resin has been described. There is.

Further, a method of identifying an alignment mark by using a template (mold) having a plurality of features for which the template alignment mark (alignment mark) contains a high absorbent is proposed (Patent Document 2).
In the invention described in Patent Document 2, it is preferable that the high absorbent has a k value (extinction coefficient) larger than 2.8 at 600 nm, and specifically, aluminum, an aluminum alloy and the like are disclosed. ..

Further, the resolution of the uneven pattern that can be distinguished by the optical microscope is limited to about 300 nm, but some inventors of the present invention have used a resin containing a fluorescent dye to distinguish the uneven pattern that can be distinguished by the fluorescent microscope. It has been proposed that the thickness can be improved to about 100 nm (Non-Patent Document 1).

Japanese Unexamined Patent Publication No. 2012-28536 Special Table 2014-522100

S. Kubo, T.M. Tomioka, M.D. Nakagawa: Jpn. J. Apple. Phys. 52,06GJ01,2013

However, in the invention described in Patent Document 1, the resolving power is lowered because the titanium oxide is mixed with the photocurable resin (see Patent Document 1 [0045]). In order to avoid a decrease in resolution, a method has been proposed in which a normal photocurable resin is used for the transferred region and a photocurable resin mixed with the titanium oxide is used only in the region having the alignment mark. However, the method in the invention described in Patent Document 1 does not solve the problem that the process becomes complicated and the resolution of the alignment mark itself is lowered due to the mixing of titanium oxide.

On the other hand, in order to have a high absorbent in the mold as in the invention described in Patent Document 2, an extra step is required in the mold manufacturing process.
Further, while the alignment accuracy is required to be in the nanometer class, it is very advantageous to improve the detection accuracy if the dimension (line width) of the alignment mark itself is also in the nanometer class. However, in dark-field reflection observation using an optical microscope as a method for identifying the alignment marks of the molds described in Patent Documents 1 and 2, a resolution of 300 nm is the theoretical limit, and 1 micrometer for practical identification. An alignment mark with the above line width is required.

Therefore, an object of the present invention is to provide an alignment method, an imprint method, and an imprint apparatus capable of improving the accuracy of alignment between a mold and a substrate.

In order to achieve the above object, the alignment method according to one aspect of the present invention includes a mold including a mold-side alignment mark having a convex or concave shape, and a mold-side moire mark having a convex or concave shape, and a fluorescent dye. A resin composition layer formed of a fluid resin composition and a patterned substrate including a convex or concave substrate-side alignment mark and a concave or convex substrate-side moire mark are laminated in this order. A laminating step and a first detection step of detecting the first misalignment of the mold side alignment mark and the substrate side alignment mark by a local difference in fluorescence intensity based on a local difference in the thickness of the resin composition layer. The first alignment step of moving the patterned substrate relative to the mold in a direction to reduce the detected first misalignment, the resin composition layer, the mold-side moiré mark, and the substrate-side moiré. The second detection step of detecting the second misalignment of the mold side alignment mark and the substrate side alignment mark based on the fluorescent moire fringes generated by the marks, and the second misalignment detected with respect to the mold in the direction of reducing the detected second misalignment. It is characterized by including a second alignment step of relatively moving the patterned substrate.

Further, in order to achieve the above object, the imprint method according to one aspect of the present invention includes a transfer region having a concavo-convex pattern, a mold-side alignment mark having a convex or concave shape, and a mold-side moire mark having a convex or concave shape. A mold containing, a curable resin composition layer formed of a curable resin composition containing a fluorescent dye and having fluidity, a region to be transferred, a substrate-side alignment mark having a convex or concave shape, and a convex or concave shape. The alignment mark on the mold side is due to the laminating step of laminating the patterned substrate containing the moiré mark on the substrate side in this order and the local difference in fluorescence intensity based on the difference in the local thickness of the curable resin composition layer. The first detection step of detecting the first misalignment of the alignment mark on the substrate side, the first alignment step of moving the patterned substrate relative to the mold in the direction of reducing the detected misalignment, and the above. A second detection step of detecting a second misalignment of the mold-side alignment mark and the substrate-side alignment mark based on the curable resin composition layer, the mold-side moire mark, and the fluorescent moire fringes generated by the substrate-side moire mark. The second alignment step of moving the patterned substrate relative to the mold in the direction of reducing the detected second misalignment, and the curing of the curable resin composition layer to form a cured resin layer. It is characterized by including a cured resin forming step for forming the mold and a peeling step for peeling the mold from the cured resin layer.

Further, in order to achieve the above object, in the imprinting apparatus according to one aspect of the present invention, a mold including a mold-side alignment mark having a convex or concave shape and a mold-side moire mark having a convex or concave shape is fixed. A fixed stage, an XYZ θ-axis movable stage on which a patterned substrate including a convex or concave substrate-side alignment mark and a convex or concave substrate-side moire mark are fixed, and an ultraviolet ray containing a fluorescent dye and having fluidity. At least three positions, a first position, a second position, and a third position, where the mold first contacts the resin pool formed by applying the curable resin composition onto the patterned substrate. It is movable to and is generated by the fluorescence field image including the mold-side alignment mark and the substrate-side alignment mark at the second position, and the mold-side moiré mark and the substrate-side moiré mark at the third position. The moiré fringe fluorescent field image including the moiré fringes is acquired, and the layer formed of the moiré-curable resin composition is cured by irradiating ultraviolet rays at the second position and the third position. The ultraviolet irradiation device for forming the cured resin layer and the ultraviolet curable resin composition applied to the patterned substrate are placed between the mold and the patterned substrate from the first position to the second position. The movement of the XYZθ-axis movable stage is controlled so that the UV-curable resin composition layer is formed by extending to the third position, and the XYZθ-axis movable is based on the fluorescence intensity distribution of the fluorescence field image. The stage is moved to at least one of the X direction, the Y direction, and the θ direction in which the first misalignment is reduced, and the XYZ θ-axis movable stage is moved to have less second misalignment based on the shading value of the moire fringe fluorescence field image. The XYZ θ-axis movable stage is moved in the Z direction so that the mold is peeled off from the cured resin layer after the cured resin layer is formed by moving the mold in at least one of the X direction, the Y direction, and the θ direction. It is characterized by including a control device for controlling the above.

According to one aspect of the present invention, it is possible to improve the accuracy of alignment between the mold and the substrate.

It is a figure explaining the alignment method by one Embodiment of this invention, and FIG. 1 (a) is a stack which laminated the resin composition layer formed by the resin composition containing a mold, a fluorescent dye, and a patterned substrate. It is a schematic plan view of a body, and FIG. 1 (b) is a schematic cross-sectional view of a laminated body cut along the line AA shown in FIG. 1 (a). 2A is a diagram illustrating an alignment method according to an embodiment of the present invention, and FIG. 2A is a schematic plan view showing an arrangement of a transfer region of a mold, a mold-side alignment mark, and a mold-side moire mark. (B) is a schematic cross-sectional view of a mold cut along the line BB shown in FIG. 2 (a). It is a figure explaining the alignment method by one Embodiment of this invention, and FIG. 3A is a plan schematic diagram which shows the arrangement of the transferred area of the patterned substrate, the substrate side alignment mark and the mold side moire mark. FIG. 3B is a schematic cross-sectional view of a patterned substrate cut along the line CC shown in FIG. 3A. It is a figure explaining the alignment method by one Embodiment of this invention, and is the schematic diagram which shows the method of acquiring the fluorescence field image of an alignment mark part and the moire fringe fluorescence field image of a moire mark part. It is a flowchart which shows the alignment method by one Embodiment of this invention. It is a figure explaining the alignment method by one Embodiment of this invention, and is the plane schematic view of the fluorescence field image of the alignment mark part. It is a figure explaining the alignment method by one Embodiment of this invention, the upper middle part of FIG. 7 is a schematic cross-sectional view of the alignment mark part, and the lower part of FIG. 7 is the fluorescence of the alignment mark part shown in the upper middle part of FIG. It is a figure which shows the strength. It is a figure explaining the alignment method by one Embodiment of this invention, and is the plane schematic view of the moire fringe fluorescence field image of a moire mark part. It is a figure explaining the alignment method by one Embodiment of this invention, and is an example of the misalignment measurement result by a moire fringe. It is a process flow diagram which shows the imprint method by one Embodiment of this invention. It is a schematic diagram which shows the structure of the imprint apparatus by one Embodiment of this invention. It is a figure explaining the imprint apparatus by one Embodiment of this invention, and is the schematic diagram which shows the optical system which also serves as a dark field reflection microscope and a fluorescence microscope. It is a figure explaining the alignment method by the modification 1 of one Embodiment of this invention, and FIG. 13A is a mold, a resin composition layer formed by the resin composition containing a fluorescent dye, and a patterned substrate. 13 (b) is a schematic cross-sectional view of the laminated body cut along the DD line shown in FIG. 13 (a). It is a figure explaining the alignment method by the modification 2 of one Embodiment of this invention, FIG. 14A is a plan view which shows the mold side alignment mark, and FIG. 14B is a substrate side. FIG. 14 (c) is a schematic plan view showing an alignment mark, and FIG. 14 (c) is a schematic plan view for explaining a method of adjusting misalignment in the rotation direction in a plane parallel to the plane of the patterned substrate.

As a result of intensive research in view of the above-mentioned problems, the inventors of the present application have no limitation on the refractive index of the mold, the substrate, the resin, and the groove depth of the alignment mark by using the resin composition containing the fluorescent dye. , It has been found that the above-mentioned problems can be solved by detecting an alignment mark having a line width of 100 nm to 1000 nm by fluorescence microscopic observation and aligning the mold and the substrate. Furthermore, the inventors of the present application use a resin composition containing a fluorescent dye to detect fluorescent moire fringes by observation with a fluorescence microscope and align the mold and the substrate to improve the alignment accuracy. Found that is possible.

Hereinafter, the positioning method, the imprinting method, and the imprinting apparatus according to the embodiment of the present invention will be described with reference to FIGS. 1 to 14. First, the alignment method according to the present embodiment will be described with reference to FIGS. 1 to 9.

(Laminated body)
First, the laminated body to which the alignment method of the present invention is carried out will be described with reference to FIGS. 1 to 3. FIG. 1A is a plan view showing a schematic configuration of a laminated body 1 used in the alignment method according to the present embodiment. FIG. 1B is a cross-sectional view showing a schematic configuration of the laminated body 1 cut along the line AA shown in FIG. 1A. FIG. 2A is a plan view showing a schematic configuration of the mold 3 used in the alignment method according to the present embodiment. FIG. 2B is a cross-sectional view showing a schematic configuration of the mold 3 cut along the line BB shown in FIG. 2A. FIG. 3A is a plan view showing a schematic configuration of the patterned substrate 7. FIG. 3B is a cross-sectional view showing a schematic configuration of the patterned substrate 7 cut along the line CC shown in FIG. 3A.

As shown in FIG. 1, the laminate 1 includes a transparent mold 3 including a mold-side alignment mark 31 having a convex or concave shape and a mold-side moire mark 33 having a convex or concave shape. Further, the laminate 1 includes a resin composition layer 5 formed of a resin composition containing a fluorescent dye and having fluidity. Further, the laminate 1 includes a patterned substrate 7 including a substrate-side alignment mark 71 having a convex or concave shape and a substrate-side moire mark 73 having a convex or concave shape. The laminated body 1 has a structure in which the mold 3, the resin composition layer 5, and the patterned substrate 7 are laminated in this order.

As shown in FIG. 1A, the laminated body 1 has a substantially square shape in a plan view. A transfer region 32 provided on the mold 3 and a transfer region 72 (not shown in FIG. 1) provided on the patterned substrate 7 are arranged so as to overlap with each other in a substantially central portion of the laminate 1. At the four corners of the laminate 1, a mold-side alignment mark 31 provided on the mold 3 surrounding the transfer region 32 and a substrate-side alignment mark provided on the patterned substrate 7 surrounding the transfer region 72 are provided. It overlaps with 71 and is arranged respectively. The region where at least a part of the mold-side alignment mark 31 and the substrate-side alignment mark 71 are overlapped is the alignment mark portion. Further, the mold-side moire mark 33 provided on the mold 3 along two of the four ends of the laminated body 1 and the substrate provided on the patterned substrate 7 along the two ends. The side moire marks 73 are arranged so as to overlap each other. The area where at least a part of the moire mark 33 on the mold side and the moire mark 73 on the substrate side are overlapped is the moire mark portion. Although details will be described later, the laminate 1 is configured to exhibit fluorescent moiré fringes by arranging the mold-side moiré mark 33 and the substrate-side moiré mark 73 on top of each other.

(mold)
As shown in FIG. 2, the mold 3 has a transfer region 32 having a desired uneven pattern to be transferred to the cured resin layer, a mold-side alignment mark 31 having a convex or concave shape as a reference for mold position information, and a mold-side. It has a moire mark 33. The transfer region 32 is provided so as to occupy a square-shaped region substantially in the center of the mold 3 in a plan view. Mold-side alignment marks 31 surround the transfer region 32 and are provided at the four corners of the mold 3. The mold-side moire mark 33 is sandwiched between two mold-side alignment marks 31 and is provided between the end side of the mold 3 and the transfer region 32. The mold-side moire mark 33 is provided along two orthogonal ends of the four ends of the mold 3.

As the forming material of the mold 3, glass, SiO ₂ , or a transparent cured resin is used. The mold 3 is a transparent plate made of these materials. Specifically, examples of the material for forming the mold 3 include quartz glass, quartz, a siloxane polymer, borosilicate glass, a fluorocarbon polymer, an organic polymer, and cured sapphire. Further, the surface of the mold 3 on the side having the transfer region in contact with the resin composition containing a fluorescent dye and having fluidity may be mold-released or may have a mold-releasing layer.

The thickness of the mold 3 is not limited as long as the strength for handling and the light transmittance are compatible. The thickness of the mold 3 may be, for example, 0.1 to 6.0 mm, or 0.3 to 1.0 mm.
The mold-side alignment mark 31 has a cross shape in a plan view, and the cross-shaped portion is formed in a concave shape. The mold-side alignment mark 31 may have a convex cross shape. The width of the mold-side alignment mark 31 may be, for example, 100 to 1000 nm or 100 to 500 nm. When the width of the mold-side alignment mark 31 is 100 nm or more, it can be detected by fluorescence observation described later. Further, when the width of the mold-side alignment mark 31 is 1000 nm or less, more precise alignment is possible. The depth of the mold-side alignment mark 31 may be, for example, 1/2 to 1/50 of the detection wavelength, or 1/8 to 1/40 of the detection wavelength. When the depth of the mold-side alignment mark 31 is 10 nm or more, the fluorescence intensity described later becomes high. Further, if the depth of the mold-side alignment mark 31 is 300 nm or less, air bubbles are unlikely to remain during resin filling. Further, with these dimensions, an unmodified mold or a mold modified with a release agent can be used.

The moiré marks 33 on the mold side are arranged in parallel at a pitch P1 of 200 nm to 20 μm, and are arranged in parallel with a plurality of first pattern portions 331 having a line width W1 of 100 nm to 10 μm at a pitch P2 of 200 nm to 20 μm. It has a plurality of second pattern portions 332 having a line width W2 of 100 nm to 10 μm. The pitch P1 of the plurality of first pattern portions 331 is from a predetermined position in one of the first pattern portions 331 of the two adjacent first pattern portions 331 to the predetermined position in the other first pattern portion 331. It is the length to the equivalent position. In FIG. 2, the predetermined position is the long side on the left side (or upper side) of the first pattern portion 331 located on the relatively left side (or upper side) of the two adjacent first pattern portions 331. The position equivalent to the predetermined position is the long side on the left side (or upper side) of the first pattern portion 331 located relatively on the right side (or lower side). The predetermined position of one of the two adjacent first pattern portions 331 and the position equivalent to the predetermined position of the other are not limited to the long side on the left side (or upper side) of the first pattern portion 331, and the first pattern It may be the long side on the right side (or the lower side) of the portion 331, or may be the midpoint of the first pattern portion 331.

Further, the pitch P2 of the plurality of second pattern portions 332 is set from a predetermined position in one of the second pattern portions 332 of the two adjacent second pattern portions 332 to the predetermined position in the other second pattern portion 332. It is the length to the position equivalent to the position. In FIG. 2, the predetermined position is the long side on the left side (or upper side) of the second pattern part 332 located on the relatively left side (or upper side) of the two adjacent second pattern parts 332. The position equivalent to the predetermined position is the long side on the left side (or upper side) of the second pattern portion 332 located relatively on the right side (or lower side). The predetermined position of one of the two adjacent second pattern portions 332 and the position equivalent to the predetermined position of the other are not limited to the long side on the left side (or upper side) of the second pattern portion 332, and the second pattern It may be the long side on the right side (or the lower side) of the portion 332, or may be the midpoint of the second pattern portion 332.

The plurality of first pattern portions 331 and the plurality of second pattern portions 332 are arranged so that the pitch difference between the pitch P1 and the pitch P2 is 20 nm to 2 μm. In the present embodiment, the pitch P1 is 4.4 μm, the pitch P2 is 4.0 μm, and the line width W1 and the line width W2 are 2.0 μm. The larger the pitch and the smaller the pitch difference between the pitch P1 and the pitch P2, the larger the enlargement ratio due to the moire fringes described later, so that high resolution can be obtained. On the other hand, in the present invention, in order to observe the moire fringes described later, alignment may be performed in a narrow observation field using a high-magnification lens. In the present invention, high resolution and the ability to observe moire fringes even in a narrow observation field are determined by mutual balance. That is, if the magnification is determined by giving priority to high resolution, the magnification of the lens is determined, so that the pitch and pitch difference suitable for this can be determined, and if the magnification of the lens is determined, high resolution can be obtained. The pitch and pitch difference suitable for the above can be determined. Considering two points, one is that the magnification due to the moiré fringes increases and alignment is easy, and the other is that the period of the moiré fringes is sufficiently within the observation field and alignment is easy even when a high-magnification lens is used. The pitch of the plurality of first pattern portions 331 and the plurality of second pattern portions 332 is preferably 200 nm or more and 20 μm or less, and the pitch difference is preferably 20 nm or more and 2 μm or less.

Furthermore, there are two viewpoints, one is that the magnification due to the moiré fringes is increased and alignment is easy, and the other is that the period of the moiré fringes is sufficiently within the observation field and alignment is easy even when a high-magnification lens is used. Considering the above, the pitch of the plurality of first pattern portions 331 and the plurality of second pattern portions 332 is 4 μm or more and 400 nm or less, and the pitch difference between the plurality of first pattern portions 331 and the plurality of second pattern portions 332 is 4 μm or more. It may be 400 nm or less.

Here, when the larger pitch is P2, that is, when the relationship of "P1 <P2" is established, the enlargement ratio MP of the moire fringes by the pitch P1 and the pitch P2 is defined by the following equation (1).
MP = P2 / (P2-P1) ... (1)

The first pattern portion 331 is formed in a rectangular shape in a plan view (see FIG. 2A). The first pattern portion 331 is formed in a concave shape in a cross-sectional view (see FIG. 2B). The plurality of first pattern portions 331 each have the same shape. The plurality of first pattern portions 331 are arranged on the end side side of the mold 3. The plurality of first pattern portions 331 are arranged side by side along two orthogonal ends of the four ends of the mold 3. The plurality of first pattern portions 331 are arranged between the two mold-side alignment marks 31.

The second pattern portion 332 is formed in a rectangular shape in a plan view (see FIG. 2A). The second pattern portion 332 is formed in a concave shape in a cross-sectional view. Each of the plurality of second pattern portions 332 has the same shape. The second pattern portion 332 has the same shape as the first pattern portion 331. The plurality of second pattern portions 332 are arranged next to the first pattern portion 331 and on the transfer region 32 side. The plurality of second pattern portions 332 are arranged side by side in the direction in which these end edges extend between the two end edges of the mold 3 in which the first pattern portion 331 is arranged and the transfer region 32.

The mold 3 can be produced by various methods. For example, an electron beam resist is applied to one main surface of a quartz glass substrate, and the uneven pattern of the transfer region 32, the mold side alignment mark 31 and the mold side moire mark 33 are drawn by electron beam and developed, and then cured. A method of dry etching a substrate with a mixed gas of tetrafluorocarbon and oxygen using a resist as a mask can be mentioned. As the mold release treatment, any mold release treatment can be used, and examples thereof include a treatment in which a mold release agent is applied with a dip coater and dried. Examples of the release agent include a silane compound having a perfluoro group.

(Resin composition layer)
The fluid resin composition containing a fluorescent dye is a curable resin composition from the viewpoint of being used in the imprint method, and contains, for example, a radical polymerization monomer or a cationic polymerization monomer, and radical-based light depending on the monomer. It may be a photocurable resin composition containing a polymerization initiator or a cationic photopolymerization initiator. The resin composition containing a fluorescent dye and having fluidity is, for example, an ultraviolet curable resin composition. The fluid resin composition containing the fluorescent dye may contain other components, for example, a polymerization inhibitor, if necessary.

The resin composition containing a fluorescent dye and having fluidity may have fluidity and a viscosity of 0.005 to 20 Pa · s. This resin composition has fluorescence that absorbs energy and excites electrons to emit light when irradiated with excitation light having a predetermined wavelength, and is irradiated with ultraviolet rays having a wavelength different from that of the excitation light. Has the property of curing.

As the radical polymerization monomer, a (meth) acrylate monomer can be preferably used, and for example, a compound such as trimethylolpropane triacrylate is exemplified.
As the photopolymerization initiator, a polymerization initiator that initiates radical polymerization by irradiation with ultraviolet rays, particularly g-rays, h-rays, and i-rays can be preferably used, and examples thereof include α-hydroxyalkylphenone, acylphosphine oxide, and oxime ester. Compounds are exemplified.
As the fluorescent dye, a compound that fluoresces when irradiated with light in the visible region where the curing reaction of the ultraviolet curable resin composition does not occur can be preferably used.

First, the absorption of the cured resin layer obtained by exposing the layer formed of the pattern-forming photocurable resin composition other than the fluorescent dye is applied to at least a part of the absorption wavelength region that emits the fluorescence of the fluorescent dye. It needs to be virtually nonexistent. That is, the fluorescent dye having absorption that emits fluorescence at least in a region of the cured resin layer obtained by exposing the layer formed of the pattern-forming photocurable resin composition, in which there is substantially no absorption other than the fluorescent dye. Is used. In other words, the absorption wavelength region that emits fluorescence in the absorption spectrum of the fluorescent dye is the absorption spectrum other than the fluorescent dye of the cured resin layer obtained by exposing the layer formed by the photocurable resin composition for pattern formation. It is necessary to have regions that do not substantially overlap. This is because the excitation of the fluorescent dye is inhibited when the absorption wavelength region that emits fluorescence in the absorption spectrum of the fluorescent dye does not have a region that does not substantially overlap with the absorption spectrum other than the fluorescent dye.

Examples of the fluorescent dye include fluorescent dyes such as fluorescent dyes and fluorescent pigments, but organic or inorganic phosphors may be used. In particular, an organic fluorescent dye may be used because it is easily dissolved in the photocurable resin composition and the fluorescence quantum yield is high. Since the photocurable resin composition of the present embodiment is used for optical nanoimprint lithography, an organic fluorescent dye that does not contain metal ions and can be finally removed by reactive ion etching or the like may be used. Examples of the organic fluorescent dye include xanthene dyes such as rhodamine (rhodamine 6G (counterionics are Cl- and BF4-), rhodamine B, etc.), coumarin dyes, oxazine dyes, stilben dyes, and aryldimetics. There are lidene pigments, cyanine pigments, pyridine pigments, quinacridone derivatives and the like.

The thickness of the resin composition layer 5 (other than the recesses such as the alignment mark) is preferably 0.1 to 10 times as high as the depth of the recesses of the mold 3. The thinner the resin composition layer 5 is 10 times or less with respect to the recesses of the mold 3, the higher the SN ratio and the easier the detection.

(Pattern board)
As shown in FIG. 3, the patterned substrate 7 has a transferred region 72 on which a cured resin layer having a desired uneven structure is laminated, and a substrate having a convex or concave shape as a reference for position information of the patterned substrate 7. It has a side alignment mark 71 and a substrate side moire mark 73. The transferred region 72 is provided so as to occupy a square-shaped region substantially at the center of the patterned substrate 7 in a plan view. The substrate-side alignment marks 71 surround the transferred region 72 and are provided at the four corners of the patterned substrate 7. The moiré mark 73 on the substrate side is sandwiched between the two alignment marks 71 on the substrate side and is provided between the end side of the patterned substrate 7 and the transferred region 72. The moiré mark 73 on the substrate side is provided along two orthogonal edges of the four edges of the patterned substrate 7.

In the patterned substrate 7, a cured resin layer having the uneven structure of the above-mentioned substrate-side alignment mark 71 is formed on a Si wafer (hereinafter, “Si wafer” may be read as “compound semiconductor wafer” such as GaAs). The laminated body, the Si wafer on which the above-mentioned substrate-side alignment mark 71 and the substrate-side moire mark 73 are formed by etching, and any of an n-layer or p-layer pattern, a wiring layer, and an insulating layer on these Si wafers. It is a substrate in which one layer or a plurality of layers are formed.

The substrate-side alignment mark 71 has a cross shape in a plan view, and the cross-shaped portion is formed in a concave shape. The substrate-side alignment mark 71 may have a convex cross shape. The width of the substrate-side alignment mark 71 may be, for example, 100 to 1000 nm or 100 to 500 nm. When the width of the substrate-side alignment mark 71 is 100 nm or more, it can be detected by fluorescence observation described later. Further, when the width of the alignment mark 71 on the substrate side is 1000 nm or less, more precise alignment is possible. The depth of the substrate-side alignment mark 71 may be, for example, 1/2 to 1/50 of the detection wavelength, or 1/8 to 1/40 of the detection wavelength. When the depth of the substrate-side alignment mark 71 is 10 nm or more, the fluorescence intensity described later becomes high. Further, if the depth of the alignment mark 71 on the substrate side is 300 nm or less, air bubbles are unlikely to remain during resin filling. Further, with these dimensions, an unmodified mold or a mold modified with a release agent can be used.

The substrate-side alignment mark 71 has substantially the same width and depth as the mold-side alignment mark 31. On the other hand, the two intersecting rod-shaped portions of the substrate-side alignment mark 71 are formed longer than the two intersecting rod-shaped portions of the mold-side alignment mark 31. When the patterned substrate 7 and the mold 3 are arranged to face each other with the photocurable resin composition interposed therebetween, the mold-side alignment mark 31 is arranged so that at least a part thereof overlaps with the substrate-side alignment mark 71. The region where the substrate-side alignment mark 71 and the mold-side alignment mark 31 overlap has a larger number of fluorescent resist dyes contained in the photocurable resin composition than the region where both marks 31 and 71 do not overlap. Therefore, the fluorescence intensity becomes stronger. Thereby, the misalignment between the mold 3 and the patterned substrate 7 can be detected based on the fluorescence intensity of the region where the substrate side alignment mark 71 and the mold side alignment mark 31 are provided.

The moiré marks 73 on the substrate side are arranged in parallel at a pitch P1 of 200 nm to 20 μm, and are arranged in parallel with a plurality of first pattern portions 731 having a line width W1 of 100 nm to 10 μm at a pitch P2 of 200 nm to 20 μm. It has a plurality of second pattern portions 732 having a line width W2 of 100 nm to 10 μm. The pitch P1 of the plurality of first pattern portions 731 is from a predetermined position in one of the first pattern portions 731 of the two adjacent first pattern portions 731 to the predetermined position in the other first pattern portion 731. It is the length to the equivalent position. In FIG. 3, the predetermined position is the long side on the left side (or upper side) of the first pattern part 731 located relatively on the left side (or upper side) of the two adjacent first pattern parts 731. The position equivalent to the predetermined position is the long side on the left side (or upper side) of the first pattern portion 731 located relatively on the right side (or lower side). The predetermined position of one of the two adjacent first pattern portions 731 and the position equivalent to the predetermined position of the other are not limited to the long side on the left side (or upper side) of the first pattern portion 731, and the first pattern It may be the long side on the right side (or the lower side) of the portion 731, or may be the midpoint of the first pattern portion 731.

Further, the pitch P2 of the plurality of second pattern portions 732 is set from a predetermined position in one of the second pattern portions 732 of the two adjacent second pattern portions 732 to the predetermined position in the other second pattern portion 732. It is the length to the position equivalent to the position. In FIG. 3, the predetermined position is the long side on the left side (or upper side) of the second pattern part 732 located relatively on the left side (or upper side) of the two adjacent second pattern parts 732. The position equivalent to the predetermined position is the long side on the left side (or upper side) of the second pattern portion 732 located relatively on the right side (or lower side). The predetermined position of one of the two adjacent second pattern portions 732 and the position equivalent to the predetermined position of the other are not limited to the long side on the left side (or upper side) of the second pattern portion 732, and the second pattern It may be the long side on the right side (or the lower side) of the portion 732, or may be the midpoint of the second pattern portion 732.

The plurality of first pattern portions 731 and the plurality of second pattern portions 732 are arranged so that the pitch difference between the pitch P1 and the pitch P2 is 20 nm to 2 μm. In the present embodiment, the pitch P1 is 4.4 μm, the pitch P2 is 4.0 μm, and the line width W1 and the line width W2 are 2.0 μm. When the pitch P1 is fixed, the larger the pitch P2 and the smaller the pitch difference between the pitch P1 and the pitch P2, the larger the enlargement ratio due to the moire fringes described later, so that high resolution can be obtained. On the other hand, in the present invention, in order to observe the moire fringes described later, alignment may be performed in a narrow observation field using a high-magnification lens. In the present invention, high resolution and the ability to observe moire fringes even in a narrow observation field are determined by mutual balance. That is, if the magnification is determined by giving priority to high resolution, the magnification of the lens is determined, so that the pitch and pitch difference suitable for this can be determined, and if the magnification of the lens is determined, high resolution can be obtained. The pitch and pitch difference suitable for the above can be determined. Considering two viewpoints, one is that the magnification due to the moiré fringes is increased and alignment is easy, and the other is that the period of the moiré fringes is sufficiently within the observation field and alignment is easy even when a high-magnification lens is used. Then, the pitch of the plurality of first pattern portions 731 and the plurality of second pattern portions 732 is preferably 200 nm or more and 20 μm or less, and the pitch difference is preferably 20 nm or more and 2 μm or less.

Furthermore, there are two viewpoints, one is that the magnification due to the moiré fringes is increased and alignment is easy, and the other is that the period of the moiré fringes is sufficiently within the observation field and alignment is easy even when a high-magnification lens is used. Considering the above, the pitch of the plurality of first pattern portions 731 and the plurality of second pattern portions 732 is 4 μm or more and 400 nm or less, and the pitch difference between the plurality of first pattern portions 731 and the plurality of second pattern portions 732 is 4 μm or more. It may be 400 nm or less.

Here, when the larger pitch is P2, that is, when the relationship of "P1 <P2" is established, the enlargement ratio MP of the moire fringes by the pitch P1 and the pitch P2 is defined by the above equation (1). ..

The second pattern portion 732 is formed in a rectangular shape in a plan view (see FIG. 3A). The second pattern portion 732 is formed in a concave shape in a cross-sectional view (see FIG. 3B). Each of the plurality of second pattern portions 712 has the same shape. The plurality of second pattern portions 732 are arranged on the end side side of the patterned substrate 7. The plurality of second pattern portions 732 are arranged side by side along two orthogonal end edges of the four end edges of the patterned substrate 7. The plurality of second pattern portions 732 are arranged between the two substrate-side alignment marks 71. The plurality of second pattern portions 732 have the same line width W1 at the same pitch P1 as the plurality of second pattern portions 332 provided on the mold 3.

The first pattern portion 731 is formed in a rectangular shape in a plan view (see FIG. 3A). The first pattern portion 731 is formed in a concave shape in a cross-sectional view. The plurality of first pattern portions 731 each have the same shape. The first pattern portion 731 has the same shape as the second pattern portion 732. The plurality of first pattern portions 731 are arranged next to the second pattern portion 732 and on the side to be transferred to the transferred region 72. The plurality of first pattern portions 731 are arranged side by side between the two ends of the patterned substrate 7 on which the second pattern portion 732 is arranged and the transferred region 72 in the direction in which these ends extend. ing. The plurality of first pattern portions 731 have the same line width W1 at the same pitch P1 as the plurality of first pattern portions 731 provided in the mold 3.

When the mold 3 and the patterned substrate 7 are arranged so as to face each other with the photocurable resin composition interposed therebetween, the formation regions of the plurality of first pattern portions 331 of the mold 3 and the plurality of second pattern portions of the patterned substrate 7 are arranged. The forming regions of 732 overlap, and the forming regions of the plurality of second pattern portions 332 of the mold 3 and the forming regions of the plurality of second pattern portions 732 of the patterned substrate 7 overlap. When the mold 3 and the patterned substrate 7 are arranged to face each other due to a slight difference between the pitch P1 and the pitch P2 (0.4 μm in this embodiment), the first pattern portion 331 and the second pattern portion 732 are densely overlapped with each other. , And the degree of overlap of the second pattern portion 332 and the first pattern portion 731 is sparse and dense. As a result, moire fringes are generated in the region where the moire mark 33 on the mold side and the moire mark 73 on the substrate side overlap (see FIG. 1A).

The moiré fringes generated by the first pattern portion 331 and the second pattern portion 732 and the moiré fringes generated by the second pattern portion 332 and the first pattern portion 731 when the mold 3 and the patterned substrate 7 overlap each other as designed are The shade period and phase match (see FIG. 1 (a)). However, if the mold 3 and the patterned substrate 7 do not overlap as designed, the moire fringes generated by the first pattern portion 331 and the second pattern portion 732 and the moire caused by the second pattern portion 332 and the first pattern portion 731 The fringes have the same shade period but are out of phase. Therefore, the phase of the moire fringes generated by the first pattern portion 331 and the second pattern portion 732 and the phase of the moire fringes generated by the second pattern portion 332 and the first pattern portion 731 are used to determine the moiré mark 33 on the mold side and the substrate side. Misalignment with the moire mark 73 can be detected.

(Alignment method)
Next, the alignment method according to the present embodiment will be described with reference to FIGS. 4 to 9. FIG. 4 is a schematic view showing a method of acquiring a fluorescence field image of an alignment mark portion and a moire fringe fluorescence field image of a moire mark portion in the alignment method according to the present embodiment. FIG. 5 is a flowchart showing an example of the flow of the alignment method according to the present embodiment. FIG. 6 is a schematic plan view of a fluorescence field image of the alignment mark portion. The upper middle part of FIG. 7 is a schematic cross-sectional view of the alignment mark portion, and the lower middle part of FIG. 7 is a diagram showing the fluorescence intensity of the alignment mark portion shown in the upper middle part of FIG. The horizontal axis in the lower middle of FIG. 7 indicates the position of the alignment portion, and the vertical axis indicates the fluorescence intensity. FIG. 8 is a moire fringe fluorescence field image of the moire mark portion. FIG. 9 is a diagram showing the fluorescence intensity of the moire mark portion shown in FIG. The horizontal axis in FIG. 9 indicates the distance from the predetermined position to each portion of the moire mark portion, and the vertical axis indicates the fluorescence intensity of the moire mark portion.

In the alignment method according to the present embodiment, the mold-side alignment mark 31 and the substrate-side alignment mark are formed due to the local difference in fluorescence intensity based on the difference in local thickness of the resin composition layer containing the fluorescent dye and having fluidity described above. The substrate side alignment mark 71 is provided for the mold 3 in which the first detection step for detecting the first misalignment of 71 and the mold side alignment mark 31 are provided in the direction of reducing the detected first misalignment. It includes a first alignment step of relatively moving the patterned substrate 7. Further, the alignment method according to the present embodiment detects the second misalignment based on the fluorescent moire fringes generated by the resin composition layer containing the fluorescent dye and having fluidity, the mold-side moire mark 33 and the substrate-side moire mark 73. It includes a second detection step and a second alignment step of moving the patterned substrate 7 relative to the mold 3 in a direction that reduces the detected second misalignment.

As shown in FIG. 4, in the present embodiment, the mold 3, the resin composition layer 5, and the patterned substrate 7 are laminated in this order (lamination step), and at least the mold side alignment mark 31 and the substrate side alignment mark 71 are laminated. The fluorescence field image of the alignment mark portion on which a part of the alignment mark is superimposed is set at a position where it can be acquired from the mold 3 side using the fluorescence microscope apparatus 103.

In this state, as shown in the flowchart shown in FIG. 5, first, in step S1, the mold-side alignment mark 31 and the substrate-side alignment mark 71 are observed in a fluorescence field of view through the transparent mold 3. In step S3 following step S1, the observed image is acquired. In step S5 following step S3, the fluorescence intensity of the alignment mark portion of the fluorescence field image acquired in step S3 is scanned to obtain a fluorescence intensity signal profile on the scan line. In step S7 following step S5, the first misalignment (dθ1) in the θ direction from the direction of the scan line in step S5 is detected, and the first misalignment (dX1) and Y in the X direction are detected from the profile obtained in step S5. The first misalignment (dY1) in the direction is detected (first detection step). In step S9 following step S7, the XYθ-axis movement amount, which is the amount that actually moves the movable stage on which the patterned substrate 7 is placed, is determined in the direction of reducing the first misalignment. In step S11 following step S9, the movable stage is moved to align (first alignment step).

In step S13 following step S11, the moiré mark 33 on the mold side and the moiré mark 73 on the substrate side are observed in the moire fringe fluorescence visual field through the transparent mold 3. In the moire fringe fluorescence visual field observation in step S13, the moire mark portion in which at least a part of the mold side moire mark 33 and the substrate side moire mark 73 are overlapped and the alignment mark portion are in the field of view of the fluorescence microscope apparatus 103. The position of the fluorescence microscope device 103 is set. The fluorescence microscope device 103 has a step S1 with respect to the mold 3 as shown on the right side in FIG. 4 so that at least one cycle of the shading of the fluorescent moire fringes generated in the moire mark portion is in the field of view of the fluorescence microscope device 103. It is set at a position farther from the position of the field of view observation in. Alternatively, the fluorescence microscope device 103 may be set at a position away from the mold 3 at a position substantially equal to the position of the visual field observation in step S1 after switching to the wide-angle lens.

In step S15 following step S13, the observed moire fringe fluorescence field image is acquired. In step S17 following step S15, the alignment portion and the moire mark portion of the moire fringe fluorescent field image acquired in step S15 are scanned to obtain a profile of the moire fringe signal on the scan line. In the profile of this fluorescent moiré fringe signal, the shade value of the fluorescent moiré fringe appears.

In step S19 following step S17, the second misalignment in the X direction (dX2), the second misalignment in the Y direction (dY2), and the second misalignment in the θ direction (dθ2) are detected from the profile obtained in step S17. (Second detection step). The second misalignment (dθ2) in the θ direction is the second misalignment dX2 + in the positive direction of X, the second misalignment dX2- in the negative direction of X, and the positive direction of Y, as in the first method described later. 2nd misalignment dY2 + and 2nd misalignment dY2- in the negative direction of Y. In step S21 following step S19, the XYθ-axis movement amount, which is the amount that actually moves the movable stage on which the patterned substrate 7 is placed, is determined in the direction of reducing the second misalignment. In step S23 following step S21, the movable stage is moved to align (second alignment step), and the alignment between the mold 3 and the patterned substrate 7 is completed.

Generally, the refractive index of the ultraviolet curable resin and the mold is about 1.45 to 1.50, which are almost the same, and when the ultraviolet curable resin is filled in the recess of the mold side alignment mark, the mold side alignment mark is optically formed. It becomes difficult to identify.
However, the resin composition layer formed of the resin composition containing the fluorescent dye can obtain the fluorescence intensity that correlates with the thickness of the resin composition layer. Therefore, for example, as shown in FIG. 6, the concavely formed mold-side alignment mark 31 is filled with the photocurable fluorescent composition, and the concavely formed substrate-side alignment mark 71 is filled with the photocurable fluorescent composition. A fluorescence field image in a filled state is acquired.

In the first method for detecting misalignment, as shown by a straight dashed arrow in FIG. 6, two or more locations in the X direction (two locations in FIG. 6) and two or more locations in the Y direction (2 in FIG. 6). Scan the fluorescence intensity at different locations. For example, the positive direction of X (the direction from the left to the right in FIG. 6) and the negative direction of X (the direction from the right to the left in FIG. One misalignment dX1 + and the first misalignment dX1- in the negative direction of X are detected. Then, for example, the positive direction of Y (the direction from the bottom to the top in FIG. 6) and the negative direction of Y (the direction from the top to the bottom in FIG. 6) are scanned one by one, for a total of two places, and the positive direction of Y is scanned. The first misalignment dY1 + and the first misalignment dY1- in the negative direction of Y are detected.

It is assumed that the mold 3 is displaced counterclockwise (counterclockwise) with respect to the patterned substrate 7. In this case, as shown in FIG. 6, a fluorescence field image in a state where the mold-side alignment mark 31 is displaced counterclockwise (counterclockwise) with respect to the substrate-side alignment mark 71 is acquired. As shown in the upper part of FIG. 7, the concave mold-side alignment mark 31 and the concave substrate-side alignment mark 71 contain more fluorescent dye contained in the resin composition layer 5 than in other regions. Therefore, when the fluorescence intensity distribution is scanned in the negative direction of X as shown by the left-pointing dashed arrow in FIG. 6, the mold-side alignment mark 31 and the substrate-side alignment mark 71 are respectively shown in the lower part of FIG. A fluorescence intensity profile is obtained in which the fluorescence intensity is relatively strong at the position. By finding the difference between the maximum points of this fluorescence intensity profile, the first misalignment dX1- in the negative direction of X is detected. The same method applies to the positive direction of X, the positive direction of Y, and the negative direction of Y. The first misalignment of X in the positive direction dX1 +, the first misalignment of Y in the positive direction dY1 +, and the first misalignment of Y in the negative direction. Alignment dY1- is detected.

When the first misalignment dX1 + and the first misalignment dX− are different, and the first misalignment dY1 + and the first misalignment dY− are different, they rotate in the θ direction (rotate in a plane parallel to the main surface of the patterned substrate 7). It means that there is a misalignment in the direction of), and it is possible to obtain the misalignment in the θ direction by calculation.

More specifically, for example, by providing a scan start point (origin) at a predetermined position in the fluorescence field image of the patterned substrate 7, the position of the substrate-side alignment mark 71 is specified, and fluorescence based on the substrate-side alignment mark 71 is specified. The maximum point of the strength profile (hereinafter, may be abbreviated as "the maximum point on the substrate side") is also specified. Therefore, in scanning the fluorescence field image in each of the positive direction of X and the negative direction of X, the maximum point of the fluorescence intensity profile based on the mold side alignment mark 31 may be abbreviated as “mold side maximum point”. ) Appears on the right side, the left side, or overlaps with the maximum point on the substrate side, so that the relative positional relationship between the patterned substrate 7 and the mold 3 can be determined.

For example, the mold-side maximal point is on the right side (or left side) in the positive direction of X, is on the left side (or right side) in the negative direction of X, and the mold-side maximal point is on the upper side (or lower side) in the positive direction of Y. ), And it is located on the lower side (or upper side) in the negative direction of Y, it can be seen that the mold 3 is rotated leftward (or rightward) with respect to the patterned substrate 7. Further, for example, the maximum point on the mold side exists on the right side (or left side) in both the positive direction of X and the negative direction of X, and the maximum point on the mold side exists on the upper side (or lower side) in the positive direction of Y. When present on the lower side (or upper side) in the negative direction of, the mold 3 is displaced to the left side (or right side) with respect to the patterned substrate 7 and is arranged to be rotated to the left side (or right side). I understand. Further, for example, the maximum point on the mold side exists on the upper side (or lower side) in both the positive direction of Y and the negative direction of Y, and the maximum point on the mold side exists on the left side (or right side) in the positive direction of X. When the mold 3 is located on the right side (or left side) in the negative direction of, the mold 3 is displaced upward (or lower side) with respect to the patterned substrate 7 and is arranged to be rotated leftward (or rightward). I understand.

As described above, in the first method, as in the second method described later, after detecting the first misalignment in the θ direction and adjusting the deviation between the mold 3 and the patterned substrate 7, the X direction and the Y It is different from the method of detecting and adjusting the first misalignment of the direction. In the first method, the first misalignment dθ1, dX1 and dY1 can be detected at the same time (step S7), the movable stage θXY movement amount can be determined at the same time (step S11), and the first alignment can be performed.

In the second method, first, the deviation angle of the parallelism between the cross-shaped mold-side alignment mark 31 and the cross-shaped substrate-side alignment mark 71 in the acquired fluorescence field image corresponds to dθ1. If there is a deviation in the θ direction (the direction of rotation in the plane parallel to the main surface of the patterned substrate 7), the XYZ θ-axis movable stage on which the patterned substrate 7 is placed is rotated by dθ to eliminate the misalignment dθ1. ..
Next, the fluorescence intensity distribution in the region including the mold-side alignment mark 31 and the substrate-side alignment mark 71 is scanned in the X and Y directions, and the relative first of the mold-side alignment mark 31 and the substrate-side alignment mark 71 is obtained. Misalignment dX1 and dY1 are detected. In the second method, since the first misalignment in the θ direction is adjusted, the first misalignment dX1 is moved by dX and dY so that the first misalignment dX1 and dY1 become zero. , DY1 can be eliminated.

As described in Non-Patent Document 1, in the case of a fluorescent field, it is possible to discriminate up to a line width of 100 nm, which is shorter than the detection limit of 300 nm in a dark field using visible light, and the alignment mark is made finer. Since it is possible to do so, it also has the effect of improving the detection accuracy.

The mold 3 and the patterned substrate 7 can be aligned with each other by using the mold-side alignment mark 31 and the substrate-side alignment mark 71. However, in the fluorescent alignment using the mold side alignment mark 31 and the substrate side alignment mark 71, it is not possible to adjust the misalignment of the mold side alignment mark 31 and the substrate side alignment mark 71 less than the line width. Therefore, in the alignment method according to the present embodiment, misalignment less than the line width of the mold side alignment mark 31 and the substrate side alignment mark 71 is adjusted by using the fluorescent moire fringes generated by the mold side moire mark 33 and the substrate side moire mark 73. It is designed to do.

When the first alignment step of step S11 shown in FIG. 5 is completed, as shown in FIG. 8, even if there is no misalignment in the rotation direction in the plane parallel to the main surface of the patterned substrate 7, the patterned substrate There may be a misalignment of less than the line width of the mold side alignment mark 31 and the substrate side alignment mark 71 in the direction along the edge of 7. FIG. 8 shows a state in which the mold 3 is displaced in the lower left direction in FIG. 8 with respect to the patterned substrate 7.

By the way, the difference between the pitch P1 (= 4.4 μm) of the first pattern portion 331 and 731 and the pitch P2 (= 4.0 μm) of the second pattern portion 332 and 732 is 0.4 μm, which is compared with the pitch P1. Then, it is a minute value. Overlapping position where the first pattern portion 331 of one of the plurality of first pattern portions 331 and the second pattern portion 732 of one of the plurality of second pattern portions 732 overlap (for example, the substrate side alignment shown in FIG. 8). The first pattern portion 331 and the second pattern portion 732 are aligned from the position closest to the mark 71 in the direction in which the plurality of first and second pattern portions 331 and 732 are lined up (for example, facing right or downward in FIG. 8). The amount of deviation increases. At a position separated from the overlapping position by a predetermined distance in the direction in which the plurality of first and second pattern portions 331 and 732 are arranged, for example, the first pattern portion 331 of the other one of the plurality of first pattern portions 331 It is arranged at an intermediate position between adjacent second pattern portions 732. The amount of deviation between the first pattern portion 331 and the second pattern portion 732 decreases as the plurality of first and second pattern portions 331 and 732 are further arranged from this intermediate position, and the plurality of first pattern portions 331 The first pattern portion 331 of the other one of the above and the second pattern portion 732 of the other one of the plurality of second pattern portions 732 overlap each other. In the vicinity of the overlapping position where the first pattern portion 331 and the second pattern portion 732 overlap, the densities of the first pattern portion 331 and the second pattern portion 732 become sparse. On the other hand, in the vicinity of the position where the first pattern portion 331 (or the second pattern portion 732) is arranged between the adjacent second pattern portions 732 (or the adjacent first pattern portions 331), the first pattern portion 331 And the density of the second pattern portion 732 becomes dense. Therefore, as shown in FIG. 8, fluorescent moire fringes in which shading is repeated at a predetermined cycle are generated in the moire mark portion where the mold-side moire mark 33 and the substrate-side moire mark 73 are overlapped. Further, the same action is performed between the second pattern portion 332 and the first pattern portion 731, and fluorescent moire fringes are generated.

Therefore, in the mold 3 and the patterned substrate 7 in the present embodiment, when the first alignment step (step S11) is completed, at least a part of the mold-side moire mark 33 and the substrate-side moire mark 73 overlap, and fluorescent moire fringes are formed. It is configured to always occur. Therefore, as shown in FIG. 8, a moire fringe fluorescence field image is acquired so as to include at least one cycle of shading of the moire fringes and the mold side alignment mark 31 and the substrate side alignment mark 71 (FIG. 5). Step S15).

Further, as shown by a straight broken line arrow in FIG. 8, the region where the first pattern portion 331 of the mold 3 and the second pattern portion 732 of the patterned substrate 7 overlap, and the second pattern portion 332 of the mold 3 The fluorescent moire fringes are scanned so that the alignment mark 71 on the substrate side is included in the region where the patterned substrate 7 and the first pattern portion 731 of the patterned substrate 7 overlap each other (step S17 in FIG. 5).

By scanning the fluorescent moiré fringes, the profile of the shade value of the fluorescent moiré fringes can be obtained. The shade value of the fluorescent moire fringes is large in the region where the resin composition layer 5 contains a large amount of fluorescent dye, that is, at least one of the substrate-side alignment mark 71, the first pattern portion 331, and the second pattern portion 732 is formed. Become.

As shown in the upper part of FIG. 9, the fluorescent moire fringes generated by the first pattern portion 331 of the mold-side moire mark 33 and the second pattern portion 732 of the substrate-side moire mark 73 on the end side (outside) of the laminated body 1. The shading profile is as follows. Repeated peaks occur in a section about 10 μm to 30 μm away from the center of the line width of the substrate-side alignment mark 71, become a broad state in a section about 30 μm to 36 μm away, and peak again in a section about 36 μm to 50 μm away. Will occur repeatedly. The section where the peak occurs in the shading profile of the fluorescent moire fringes is a section in which the first pattern portion 331 and the second pattern portion 732 are in a sparse state. On the other hand, the section in the broad state sandwiched between the sections where the peaks occur in the shading profile of the fluorescent moire fringes is the section in which the first pattern portion 331 and the second pattern portion 732 are in a dense state. Therefore, the fluorescent moire fringes on the end side (outside) of the laminated body 1, that is, the downward broken line arrow on the right side in FIG. 8 become dark for the first time in a section about 30 to 35 μm away from the substrate side alignment mark 71. Here, a position separated from the substrate-side alignment mark 71 by a distance D1 (= 33.9 μm) is used as a representative value of the section in which the fluorescent moire fringes are darkened for the first time.

As shown in the lower middle of FIG. 9, fluorescent moire fringes generated by the second pattern portion 332 of the mold-side moire mark 33 and the first pattern portion 731 of the substrate-side moire mark 73 on the transfer region 32 side (inside) of the laminate 1. The shading profile of is as follows. The peak repeatedly occurs in a section about 10 μm to 39 μm away from the center of the line width of the substrate side alignment mark 71, becomes a broad state in a section about 39 μm to 45 μm away, and peaks again in a section about 45 μm to 53 μm away. Will occur repeatedly. The section where the peak occurs in the shading profile of the fluorescent moire fringes is a section in which the second pattern portion 332 and the first pattern portion 731 are in a sparse state. On the other hand, the section in the broad state sandwiched between the sections where the peaks occur in the shading profile of the fluorescent moire fringes is the section in which the second pattern portion 332 and the first pattern portion 731 are in a dense state. Therefore, the fluorescent moire fringes on the transfer region 32 side (inside) of the laminated body 1, that is, the downward broken line arrow on the left side in FIG. 8 become dark for the first time in a section about 39 to 45 μm away from the substrate side alignment mark 71. Here, a position separated from the substrate-side alignment mark 71 by a distance D2 (= 41.7 μm) is used as a representative value of the section in which the fluorescent moire fringes are darkened for the first time.

As described above, the fluorescent moiré fringes have different phases on the outside and the inside. When the phase difference between the two fluorescent moire fringes is represented by d (= D2-D1), the pitch P1 is represented by P1, and the pitch P2 is represented by P2, the deviation amount Δl between the mold 3 and the patterned substrate 7 is as follows. It can be expressed by the equation (2). The numerator term in the formula (2) is an absolute value.
Δl = ((P2-P1) / (P1 + P2)) × d ... (2)

Here, when P1 = 4.4 μm, P2 = 4.0 μm, and d = 7.8 μm (= 41.7-33.9) are substituted into the equation (2), the amount of deviation between the mold 3 and the patterned substrate 7 is reduced. Δl is determined to be 370 nm. By using the fluorescent moire fringes in this way, it is possible to detect misalignment of the mold-side alignment mark 31 and the substrate-side alignment mark 71 with a line width of less than 2 μm.

In the alignment method according to the present embodiment, the deviation amount Δl in the X direction (horizontal direction in FIG. 8) obtained by the equation (2) is defined as the second misalignment dX2, and the deviation in the Y direction (vertical direction in FIG. 8). The amount Δl is set to the second misalignment dY2 (step S19 in FIG. 5), and the XY-axis movement amount of the movable stage is determined so that the second misalignment dX2 and dY2 become zero (step S21 in FIG. 5). In the alignment method according to the present embodiment, the movable stage is moved based on the determined XY axis movement amount, and the second alignment is adjusted so that the line width of the mold side alignment mark 31 and the substrate side alignment mark 71 is less than 2 μm. Execute (step S23 in FIG. 5).

As described above, according to the alignment method according to the present embodiment, it is possible to improve the accuracy of alignment between the mold and the substrate.

(Imprint method)
Next, the imprint method according to the present embodiment will be described with reference to FIG.
FIG. 10 is a process diagram showing an example of the imprint method according to the present embodiment. The coating method of the photocurable composition at the time of laminating is not limited, and various coating methods such as a spin coating method, an inkjet method, a microgravure method, and a screen printing method can be used.

The laminating process shown in FIG. 10A will be described. In the present embodiment, as shown in the upper part of FIG. 10A, first, a curable resin composition containing a fluorescent dye and having fluidity is dropped onto the patterned substrate 7 from the nozzle of the coating device 109 and cured. A resin pool 50 formed of the sex resin composition is formed. Next, as shown in the lower part of FIG. 10A, the mold 3 is brought into contact with the resin pool 50, and the mold-side alignment mark 31, the substrate-side alignment mark 71, and the substrate-side alignment mark 71 having a convex or concave shape (concave shape in this example). The transferable region 72 is filled with the curable resin composition 50a. For example, using a curable resin composition having a low viscosity, the central portion of the mold 3 is in contact with the resin pool 50 first, and the curable resin composition is spread outward while the peripheral portion is gradually in contact with the resin pool 50. By laminating, it is possible to prevent bubbles from entering the layer formed of the curable resin composition.

Since the first detection step and the subsequent first alignment step shown in FIG. 10B are steps using the above-mentioned alignment method, description thereof will be omitted. As shown in FIG. 10B, when acquiring the fluorescence field image in the first detection step, the fluorescence field images of a plurality of alignment portions may be acquired at the same time by using a plurality of fluorescence microscope devices 103. One fluorescence microscope apparatus 103 may be used to sequentially acquire fluorescence field images of a plurality of alignment units. Further, since the second detection step shown in FIG. 10C and the subsequent second alignment step are steps using the above-mentioned alignment method, the description thereof will be omitted. In the second detection step, as shown in FIG. 10C, when acquiring a moire fringe fluorescence field image in the second detection step, a plurality of fluorescence microscope devices 103 are used to obtain moire fringes in a plurality of moire mark portions. The fluorescence field images may be acquired at the same time, or the moire fringe fluorescence field images of a plurality of moire mark portions may be sequentially acquired by using one fluorescence microscope apparatus 103.

Between the laminating step shown in FIG. 10 (a) and the first detection step shown in FIG. 10 (b), the filling state of the curable resin in the vicinity of the alignment mark portion and the moire mark portion was observed with an optical microscope in a dark field. An inspection process may be included. When bubbles are present, the difference in refractive index between the bubbles and the resin layer is large, so that the presence of bubbles can be detected. In this inspection step, the mold-side alignment mark 31 and the mold-side moire mark 33 of the mold 3 and the substrate-side alignment mark 71 and the substrate-side moire mark 73 of the patterned substrate 7 are not sufficiently filled with the curable resin composition 50a. Inspect if air bubbles remain.

Here, when the above-mentioned dark field observation is used as the conventional method for identifying the alignment mark, the titanium oxide and the high absorbent interfere with the detection of bubbles, so that the filling of the curable resin is completed using visible light. It is difficult to optically determine what has been done. On the other hand, in the present embodiment, since the alignment mark can be identified by the fluorescence visual field observation, it is possible to introduce an inspection step capable of determining the filling state of the curable resin in advance.

The cured resin forming step shown in FIG. 10D will be described. In the state where the mold 3 and the patterned substrate 7 are aligned in the first and second alignment steps described above, the curable resin composition 50a is cured by irradiating the transparent mold 3 with energy rays E. A concavo-convex structure 75 in which the fine concavo-convex pattern of the mold 3 is inverted can be provided in the transferred region 72 of the patterned substrate 7. From the viewpoint that the curing treatment time is short, an ultraviolet curable type or a resin composition may be used as the curable resin composition and cured by ultraviolet irradiation, or may be cured by an electron beam or a heat ray.

The peeling step shown in FIG. 10 (e) will be described. By lowering the XYZθ movable stage (not shown) in the Z direction (the direction in which the mold 3 and the patterned substrate 7 are overlapped), the mold 3 can be released from the resin composition layer 5.

(Imprint device)
Next, the imprinting apparatus according to the present embodiment will be described with reference to FIGS. 11 and 12. FIG. 11 is a diagram showing a schematic configuration of the imprinting apparatus 100 according to the present embodiment.
The imprinting apparatus 100 according to the present embodiment is characterized in that by using the curable resin composition as described above for the resin layer, it is possible to identify alignment marks having a finer line width by observing the fluorescence field. Further, the imprint device 100 can align the mold 3 with the patterned substrate 7 even if the error is less than the line width of the mold side alignment mark 31 and the substrate side alignment mark 71 by observing the moire fringe fluorescence visual field.
For other configurations, for example, the movable mechanism of the stage that contacts the mold and the curable resin composition layer and releases the mold and the curable resin layer, and the ultraviolet irradiation unit, the configuration of the conventional imprint device can be applied.

As shown in FIG. 11, the imprinting apparatus 100 according to the present embodiment has a fixed stage 107 for holding the mold 3 and a coating apparatus 109 for forming the resin before curing on the patterned substrate 7. Further, the imprinting apparatus 100 holds the patterned substrate 7 and brings the mold 3 and the uncured resin layer formed on the patterned substrate 7 into contact with each other or releases the mold, and further, the mold 3 and the pattern are formed. It has an XYZ θ-axis movable stage 111 for moving the patterned substrate 7 in order to align with the attached substrate 7. Further, the imprint device 100 includes an ultraviolet irradiation device 105 for curing the ultraviolet curable resin composition, a fluorescence field image of the mold side alignment mark 31 and the substrate side alignment mark 71 of the mold 3, and the mold side moire mark 33 and the substrate side moire. It has a fluorescence microscope apparatus 103 that acquires a moire fringe fluorescence field image based on the mark 73. Further, the imprint device 100 has a control device 101 that controls a coating device 109, an XYZ θ-axis movable stage 111, an ultraviolet irradiation device 105, and a fluorescence microscope device 103, and calculates misalignment from an image.

Fluorescence microscope apparatus 103 includes a central portion and smaller than the distance between the fixed stage 107 and XYZθ axis movable stage 111 is the central portion alignment mark areas Contact and moire intervals predetermined value between the fixed stage 107 and XYZθ axis movable stage 111 It is configured to be movable to at least three positions of the mark portion.

The control device 101 spreads the ultraviolet curable resin composition applied to the patterned substrate 7 between the mold 3 and the patterned substrate 7, and forms an ultraviolet curable resin composition with the ultraviolet curable resin composition. as things layer is formed, the movement of XYZθ axis movable stage 111 realm either et alignment mark portion between is provided realm Contact and moiré mark portion provided in the transfer region 32 and the transfer region 72 To control. Further, the control device 101 acquires the first misalignment of the mold-side alignment mark 31 and the substrate-side alignment mark 71 in the X-direction, Y-direction, and θ-direction based on the fluorescence intensity distribution of the fluorescence field image, and the XYZ θ-axis movable stage. The 111 is moved to at least one of the X direction, the Y direction, and the θ direction in which the first misalignment is reduced. Further, the control device 101 acquires the second misalignment of the moiré mark 33 on the mold side and the moiré mark 73 on the substrate side in the X and Y directions based on the fluorescence intensity of the moiré fringe fluorescence field image, and sets the XYZ θ-axis movable stage 111. The second misalignment is reduced in at least one of the X direction and the Y direction. Further, the control device 101 moves the XYZ θ-axis movable stage 111 in the Z direction so that the mold 3 is peeled off from the cured resin layer after the cured resin layer is formed so that the distance from the fixed stage 107 is widened. Control.

The imprint device 100 includes these devices 101 to 111, and is a device that aligns and imprints the mold 3 and the patterned substrate 7.

Further, the imprint device 100 may include a dark field reflection type optical microscope device (not shown). In this case, the imprint device 100 is configured so that the fluorescence microscope device 103, the dark field reflection type optical microscope, and the ultraviolet irradiation device 105 can be interchanged and arranged on the mold 3.

Further, the imprint device 100 may be a fluorescence microscope device having an optical system that also serves as a dark field reflection type optical microscope device and a fluorescence microscope device. FIG. 12 is a schematic view of an observation system provided in a fluorescence microscope device having an optical system that also serves as such two microscope devices.
The fluorescence microscope device having an optical system that also serves as two microscope devices can be switched between the fluorescence observation system 200 as shown in FIG. 12 (a) and the dark field observation system 300 as shown in FIG. 12 (b). It is a system. As shown in FIG. 12A, in the fluorescence observation system 200, the light source 201, the excitation filter 203 that extracts light having a wavelength necessary for exciting the fluorescent substance from the light source 201, and the light that has passed through the excitation filter 203 are incident. It has a dichroic mirror 205 and an objective lens 211 that focuses the light reflected by the dichroic mirror 205 on the laminate 1. Further, the fluorescence observation system 200 includes a fluorescence filter 207 that emits light from the laminate 1 and removes noise from the light transmitted through the objective lens 211 and the dichroic mirror 205, and a detector 209 that detects the light transmitted through the fluorescence filter 207. Have. The dichroic mirror 205 can be made of a multilayer optical thin film so as to reflect light having a wavelength used for exciting a fluorescent dye and transmit light having a wavelength of fluorescence.

Further, the dark field observation system 300 includes a light source 201, a ring aperture 301 that converts the light from the light source 201 into a ring-shaped light, and a perforated mirror 303 that reflects the light that has passed through the ring aperture 301 toward the laminated body 1. It also has a condensing lens 305 that collects the light reflected by the perforated mirror 303 on the laminated body 1, and a detector 209 that detects the light reflected by the laminated body 1. The light source 201 and the detector 209 are shared by the fluorescence observation system 200 and the dark field observation system 300.

According to the imprinting apparatus 100 according to the present embodiment, there are no restrictions on the refractive index of the mold, the substrate, the resin, and the groove depth of the alignment mark, the alignment mark having a line width of 100 nm to 1000 nm can be identified, and the moire fringes. The mold 3 and the patterned substrate 7 can be aligned and imprinted with high alignment accuracy. Further, the imprinting apparatus 100 according to the present embodiment can align the mold 3 and the patterned substrate 7 with high alignment accuracy and imprint without controlling the temperature and humidity.

(Example)
Hereinafter, the present embodiment will be described in more detail with reference to Examples.
As a mold, a transparent laminated resin layer having a mold-side alignment mark having a cross-shaped concave shape having a line width of 500 nm and a depth of 100 nm is formed on a silica substrate having a length of 25 mm, a width of 25 mm, and a thickness of 1 mm. I prepared my body. Here, the transparent cured resin layer is a layer prepared by photocuring a UV-curable resin composition in which the radical polymerization type monomer glycerol 1,3-digycerolate diacrylate and the photopolymerization initiator Irgacure907 have a mass ratio of 95: 5. is there. The mold was released with (tridecafluoro-1,1,2,2-ttrahydrooctyl) trimethoxysilane. As shown in FIG. 2, four mold-side alignment marks are formed at positions corresponding to the corners of the virtual square. The distance between the centers of adjacent mold-side alignment marks (cross-shaped intersections) is 140 μm. Further, the moiré mark on the mold side is formed along two orthogonal ends of the mold. The pitch P1 of the first pattern portion provided on the moiré mark on the mold side is 4.4 μm, the line width W1 is 2 μm, the pitch P2 of the second pattern portion is 4 μm, and the line width W2 is 2 μm. In this embodiment, no transfer pattern is formed in the transfer region of the mold.

Next, as a patterned substrate, a cured resin layer having a cross-shaped concave shape having a line width of 500 nm and a depth of 100 nm and having a substrate-side alignment mark is formed on a silicon substrate having a length of 7 mm, a width of 7 mm, and a thickness of 0.525 mm. A laminated body was prepared. The substrate-side alignment marks are formed at positions corresponding to the four corners of a 150 μm square so as to overlap the mold-side alignment marks when the mold is superposed on the patterned substrate. Further, the moiré mark on the substrate side is provided along two orthogonal ends of the patterned substrate so as to overlap the moiré mark on the mold side when the mold is superposed on the patterned substrate. The pitch P1 of the first pattern portion provided on the moiré mark on the substrate side is 4.4 μm, the line width W1 is 2 μm, the pitch P2 of the second pattern portion is 4.0 μm, and the line width W2 is 2 μm. is there. Here, the cured resin layer is a layer prepared by photocuring an ultraviolet curable composition in which a radical polymerization type monomer bisphenol A glycerlate dimethacrylate and a photopolymerization initiator Irgacure907 have a mass ratio of 95: 5.

Next, as an ultraviolet curable resin composition containing a fluorescent dye, a radical polymerization monomer glycerol 1,3-diglycerate dialclylate, a photopolymerization initiator Irgacure907, and a fluorescent dye rhodamine 6G-BF4 are mixed at a mass ratio of 95: 5: 0.05. Then, a composition diluted with the solvent 1-methoxy-2-propanol was prepared. The viscosity of this ultraviolet curable resin composition after removing the solvent was 12950 mPa · s.

First, an ultraviolet curable resin composition containing a fluorescent dye was applied by spin coating on a patterned substrate and fixed on an XYZ θ-axis movable stage of an imprinting apparatus. The patterned substrate is fixed to such an extent that it does not shift with respect to the XYZθ-axis movable stage when the XYZθ-axis movable stage is moved during alignment. In this embodiment, the ultraviolet curable resin composition was applied using a spin coating device instead of the coating device 109 shown in FIG. Next, the mold was fixed to the fixing stage. The mold is fixed to the fixed stage with a strength that does not drop from the fixed stage when faced with the patterned substrate. The method of fixing the patterned substrate to the XYZθ-axis movable stage and the method of fixing the mold to the fixed stage are as long as the patterned substrate and the mold can be easily removed from each stage after the imprint is completed. There are no particular restrictions.

A patterned substrate coated with an ultraviolet curable resin composition using an XYZ θ-axis movable stage in a PFP (pentafluoropropane) atmosphere, which is a condensing gas for the purpose of preventing the occurrence of bubble defects, is placed in the Z-axis direction (patterned substrate). The UV curable resin composition on the patterned substrate is brought into contact with the mold, and the fluorescence microscope device is set as the optical system for the dark field reflection observation system to darken it. While observing the field, the Z-axis was adjusted until the alignment mark could not be identified, and it was confirmed that the alignment mark was filled with the photocurable fluorescent composition without bubbles. The thickness of the layer formed of the ultraviolet curable fluorescent composition at the completion of filling is about 300 nm.

Next, the fluorescence microscope device was switched to the optical system for the fluorescence field observation system, and a fluorescence field image including the mold side alignment mark and the substrate side alignment mark was acquired. Although not shown, alignment marks that could not be identified in the darkfield field image could be easily identified in the fluorescence field image. In addition, the fluorescence intensity characteristics could be obtained by scanning the fluorescence field image. Using the acquired fluorescence intensity, the relative position information of the mold side alignment mark and the substrate side alignment mark was acquired. Based on the acquired position information, the mold and the patterned substrate were aligned with each other in a fluid state.

Next, the fluorescence moire fringes generated in the moire mark portion were observed using a fluorescence microscope apparatus switched to the optical system for the fluorescence field observation system, and a moire fringe fluorescence field image was taken. By scanning the captured moiré fringe fluorescence field image, the characteristics of the shading value of the moiré fringe could be obtained. Using the obtained light and shade values of the fluorescent moire fringes, the relative position information of the mold side alignment mark and the substrate side alignment mark was acquired. Based on the acquired position information, the mold and the patterned substrate were aligned with each other in a fluid state.

Finally, the ultraviolet curable resin composition layer was cured by irradiation with ultraviolet rays having a wavelength of 365 nm to obtain a cured resin layer, and the mold was released between the mold and the cured resin layer.
As described above, in the above-described embodiment, the alignment marks having a line width of 500 nm and a depth of 100 nm are used, and the distance between the mold side alignment mark and the substrate side alignment mark in the X and Y directions is designed to be 5 μm. is there.

Here, regarding the size of the alignment mark, as described in Non-Patent Document 1, good identification is possible even at 100 nm, and the line width may be made finer. Further, even if the depth of the alignment mark is less than 100 nm, there is a correlation between the fluorescence intensity and the thickness, so that the depth may be further reduced. When the line width is 100 nm, the distance between the mold-side alignment mark and the substrate-side alignment mark can be narrowed to 1000 nm.

Further, even if the radical polymerization monomer was glycerol 1,6-diglycerlate diacrylate (viscosity 6 mPa · s) or glycerol 1,10-diglycerlate diacrylate (viscosity 10 mPa · s), the same results as described above were obtained.

(Modification example 1)
The laminated body in the first modification of the present embodiment will be described with reference to FIG. The components having the same functions and functions as those of the laminated body 1 shown in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIGS. 13 (a) and 13 (b), the laminate 10 in the first modification of the present embodiment has a mold-side alignment mark 31 having a convex or concave shape and a mold-side having a convex or concave shape. A transparent mold 30 including a moire mark 33 is provided. Further, the laminate 10 includes a resin composition layer 5 formed of a resin composition containing a fluorescent dye and having fluidity. Further, the laminate 10 includes a patterned substrate 70 including a substrate-side alignment mark 71 having a convex or concave shape and a substrate-side moire mark 73 having a convex or concave shape. The laminated body 10 has a structure in which the mold 3, the resin composition layer 5, and the patterned substrate 7 are laminated in this order.

Unlike the mold 3 in the above embodiment, the mold 30 has a mold-side moire mark 33 provided along each of the four end sides of the mold 30. The mold-side moire marks 33 provided along each end side are arranged in parallel at a pitch P1 of 200 nm to 20 μm, and a plurality of first pattern portions 331 having a line width W1 of 100 nm to 10 μm and 200 nm to 20 μm. It is arranged in parallel at the pitch P2 of the above, and has a plurality of second pattern portions 332 having a line width W2 of 100 nm to 10 μm. The plurality of first pattern portions 331 that are arranged to face each other with the transfer region 32 interposed therebetween are arranged so as to be point-symmetrical with the center of the transfer region 32 as the axis of symmetry. The plurality of first pattern portions 331 that are arranged to face each other with the transfer region 32 interposed therebetween are arranged so as to be point-symmetrical with the center of the transfer region 32 as the axis of symmetry.

Unlike the patterned substrate 7 in the above embodiment, the patterned substrate 70 has a moiré mark 73 on the substrate side provided along each of the four end sides of the patterned substrate 70. The moiré marks 73 on the substrate side provided along each end side are arranged in parallel at a pitch P1 of 200 nm to 20 μm, and a plurality of first pattern portions 731 having a line width W1 of 100 nm to 10 μm and 200 nm to 20 μm. It is arranged in parallel at the pitch P2 of the above, and has a plurality of second pattern portions 732 having a line width W2 of 100 nm to 10 μm. The plurality of first pattern portions 731 that are arranged so as to face each other with the transferred region 72 interposed therebetween are arranged so as to be point-symmetrical with the center of the transferred region 72 as the axis of symmetry. The plurality of second pattern portions 732 arranged so as to face each other with the transferred region 72 interposed therebetween are arranged so as to be point-symmetrical with the center of the transferred region 72 as the axis of symmetry.

The mold 30 in this modification has mold-side moire marks 33 along the four end sides, respectively. Further, the patterned substrate 70 in this modification has a moiré mark 73 on the substrate side along each of the four end edges. As a result, in this modification, misalignment in the rotation direction in the plane parallel to the main surface of the patterned substrate 70 is detected by using the moire fringe fluorescent field image, and misalignment less than the line width of the alignment mark is detected. The mold 30 and the patterned substrate 70 can be aligned with each other. For example, the second misalignment dX2 + in the positive direction of X is acquired from the moire fringe fluorescence field image based on the upper moire mark in FIG. 13, and the second misalignment dX2 + in the negative direction of X, for example, is obtained from the moire fluorescence field image based on the lower moire mark. Two misalignment dX2- is acquired. Further, for example, the second misalignment dY2 + in the positive direction of Y is acquired from the moire fringe fluorescence field image based on the left moire mark in FIG. 13, and the second misalignment dY2 + in the positive direction of Y is obtained from the moire fluorescence field image based on the moire mark on the right side, for example, in the negative direction of Y. Acquire the second misalignment dY2-. It is possible to acquire the second misalignment dθ2 in the θ direction based on the acquired second misalignment dX2 + and the second misalignment dX2- and the acquired second misalignment dY2 + and the second misalignment dY2-. it can.

(Modification 2)
The mold and the patterned substrate in the second modification of the present embodiment will be described with reference to FIG.
As shown in FIG. 14A, the mold in the present modification has a convex or concave shape and a cross-shaped mold side alignment mark 31 in a plan view, similarly to the mold 3 in the above embodiment. .. On the other hand, as shown in FIG. 14B, the patterned substrate in this modification has a convex or concave shape and has a substrate-side alignment mark 76 in which four L-shaped portions are paired in a plan view. ing.

When the mold is superposed on the pattern substrate in a state of being rotated in a plane parallel to the main surface of the patterned substrate, the mold side alignment mark 31 becomes this as shown on the left side of the thick arrow in FIG. 14 (c). It is rotated in the plane with respect to the alignment mark 76 on the substrate side (counterclockwise in FIG. 14C) and superposed. Also in this modification, by using the above-mentioned first method or the second method, as shown on the right side of the thick arrow in FIG. 14 (c), the mold side alignment mark 31 is replaced with the substrate side alignment mark 76. It can be arranged between the four L-shaped portions that constitute it. After that, by using the fluorescent moire fringes, the mold-side alignment mark 31 can be arranged substantially in the center between the four L-shaped portions constituting the substrate-side alignment mark 76.

The present invention is not limited to the above embodiment and can be modified in various ways.
In the above embodiment, the second misalignment is detected by using the fluorescent moire fringes generated in each of the two rows in which the first pattern portion and the second pattern portion are overlapped, but the present invention is not limited to this. .. For example, even if the strain obtained by comparing the fluorescent moiré fringes generated in one row in which the first pattern portion and the second pattern portion are overlapped with the fluorescent moiré fringes based on the design value is adjusted to be zero. , The same effect as that of the above embodiment can be obtained.

Further, the shapes of the mold-side alignment mark and the substrate-side alignment mark are not limited to the shapes in the above-described embodiment and the second modification, and various alignment mark shapes can be used.

The above-described embodiment exemplifies an apparatus or method for embodying the technical idea of the present invention, and the technical idea of the present invention specifies the material, shape, structure, arrangement, etc. of the component parts. Not something to do. The technical idea of the present invention may be modified in various ways within the technical scope specified by the claims stated in the claims.

The method and apparatus of the present invention can be used for manufacturing semiconductor devices and printed wiring boards.

1,10 Laminated body 3,30 Mold 5 Resin composition layer 7,70 Patterned substrate 31 Mold side alignment mark 32 Transfer area 33 Mold side moire mark 71,76 Substrate side alignment mark 72 Transfer area 73 Substrate side moire mark 75 Concavo-convex structure 100 Imprint device 103 Fluorescence microscope device 105 Ultraviolet irradiation device 107 Fixed stage 109 Coating device 111 XYZ θ-axis movable stage 331,731 First pattern part 332,732 Second pattern part

Claims (11)

A mold containing a mold-side alignment mark having a convex or concave shape and a mold-side moire mark having a convex or concave shape, a resin composition layer formed of a resin composition containing a fluorescent dye and having fluidity, and a convex shape. Alternatively, a laminating step of laminating a patterned substrate including a concave-shaped substrate-side alignment mark and a concave-shaped or convex-shaped substrate-side moire mark in this order,
A first detection step of detecting the first misalignment of the mold side alignment mark and the substrate side alignment mark by a local difference in fluorescence intensity based on a local difference in the thickness of the resin composition layer.
A first alignment step of moving the patterned substrate relative to the mold in a direction that reduces the detected first misalignment.
A second detection step of detecting a second misalignment of the mold-side alignment mark and the substrate-side alignment mark based on the fluorescent moire fringes generated by the resin composition layer, the mold-side moire mark, and the substrate-side moire mark.
A positioning method comprising a second alignment step of moving the patterned substrate relative to the mold in a direction that reduces the detected second misalignment. The alignment method according to claim 1, wherein the line width of the mold-side alignment mark or the substrate-side alignment mark is in the range of 100 nm to 1000 nm. The mold-side moire mark and the substrate-side moire mark are
A plurality of first pattern portions arranged in parallel at a pitch of 200 nm to 20 μm and having a line width of 100 nm to 10 μm.
The alignment method according to claim 1 or 2, which is arranged in parallel at a pitch of 200 nm to 20 μm and has a plurality of second pattern portions having a line width of 100 nm to 10 μm. The mold-side moire mark and the substrate-side moire mark are
The difference between the pitch of the plurality of first pattern portions and the pitch of the plurality of second pattern portions is 20 nm to 2 μm.
The alignment method according to claim 3. It is formed of a mold containing a transfer region having an uneven pattern, a mold-side alignment mark having a convex or concave shape, and a mold-side moire mark having a convex or concave shape, and a curable resin composition containing a fluorescent dye and having fluidity. A laminating step of laminating a cured resin composition layer and a patterned substrate including a transferred region, a substrate-side alignment mark having a convex or concave shape, and a substrate-side moire mark having a convex or concave shape in this order.
The first detection step of detecting the first misalignment of the mold side alignment mark and the substrate side alignment mark by the local difference in fluorescence intensity based on the local difference in the thickness of the curable resin composition layer.
A first alignment step of moving the patterned substrate relative to the mold in a direction that reduces the detected misalignment.
A second detection step of detecting a second misalignment of the mold side alignment mark and the substrate side alignment mark based on the fluorescent moire fringes generated by the curable resin composition layer, the mold side moire mark and the substrate side moire mark. When,
A second alignment step of moving the patterned substrate relative to the mold in a direction that reduces the detected second misalignment.
A curing resin forming step of curing the curable resin composition layer to form a cured resin layer,
An imprint method comprising a peeling step of peeling the mold from the cured resin layer. 5. A claim 5 including an inspection step of observing the filling state of the curable resin composition layer in the vicinity of the alignment mark portion and the moire mark portion with an optical microscope in a dark field between the laminating step and the first detection step. The described imprint method. The imprint method according to claim 5 or 6, wherein the line width of the mold-side alignment mark or the substrate-side alignment mark is in the range of 100 nm to 1000 nm. The mold-side moire mark and the substrate-side moire mark are
A plurality of first pattern portions arranged in parallel at a pitch of 200 nm to 20 μm and having a line width of 100 nm to 10 μm.
The imprint method according to claim 6 or 7, which is arranged in parallel at a pitch of 200 nm to 20 μm and has a plurality of first pattern portions having a line width of 100 nm to 10 μm. A fixed stage on which the mold containing the convex or concave mold-side alignment marks and the convex or concave mold-side moire marks are fixed,
An XYZ θ-axis movable stage to which a patterned substrate including a convex or concave substrate-side alignment mark and a convex or concave substrate-side moire mark is fixed,
The first position, the second position, and the second position where the mold first contacts the resin pool formed by applying the ultraviolet curable resin composition containing a fluorescent dye and having fluidity on the patterned substrate. A fluorescence field image including the mold-side alignment mark and the substrate-side alignment mark at the second position and the mold-side moire at the third position, which can be moved to at least three positions with respect to the three positions. A fluorescence microscope apparatus for acquiring a moiré fringe fluorescence field image including a moiré fringe generated by the mark and the moiré mark on the substrate side, and a fluorescence microscope apparatus.
An ultraviolet irradiation device that irradiates ultraviolet rays at the second position and the third position to cure the layer formed of the ultraviolet curable resin composition to form a cured resin layer.
The ultraviolet curable resin composition applied to the patterned substrate is extended from the first position to the second position and the third position between the mold and the patterned substrate to cure the ultraviolet rays. The movement of the XYZθ-axis movable stage is controlled so that the mold resin composition layer is formed, and the XYZθ-axis movable stage is moved in the X direction with less first misalignment based on the fluorescence intensity distribution of the fluorescence field image. The XYZ θ-axis movable stage is moved to at least one of the Y direction and the θ direction, and the XYZ θ-axis movable stage is moved to at least one of the X direction, the Y direction, and the θ direction based on the shading value of the moire fringe fluorescence field image. An imprint device including a control device that controls the movement of the XYZ θ-axis movable stage in the Z direction so that the mold is peeled off from the cured resin layer after the cured resin layer is formed. The imprint device according to claim 9, wherein the fluorescence microscope device can switch between an optical system for a fluorescence observation system and an optical system for a dark field reflection observation system. Further equipped with a dark field reflection type optical microscope device,
The imprint device according to claim 9 or 10, wherein the dark field reflection type optical microscope device observes the ultraviolet curable resin composition layer at the second position.

Images