JP2018186107A - Manufacturing method of microstructure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of microstructure which allows for highly accurate alignment of a transferred material and a mold, while preventing impairment of the mold.SOLUTION: A manufacturing method of microstructure includes a transfer step of transferring a transfer pattern 24 to a transferred resin layer 1, by hardening the transferred resin layer 1 while pressing the transfer pattern 24, provided in a mold 20, against the transferred resin layer 1 obtained by coating a transferred material 10 with a curable resin composition. The transferred material 10 includes a transferred material side alignment pattern 13, and the mold 20 includes a mold side alignment pattern 23. Prior to the transfer step, the manufacturing method includes an alignment step of aligning the mold 20 with the transferred material 10, by engaging the mold side alignment pattern 23 with the transferred material side alignment pattern 13 while bending the mold 20.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for manufacturing a fine structure.

  The imprint technique is a fine processing technique in which a mold having a concavo-convex pattern is pressed against a transfer material such as a liquid resin on a substrate, thereby transferring the pattern of the mold to the transfer material. The fine concavo-convex pattern ranges from a nanoscale pattern of 10 nm to about 100 μm, and is used in various fields such as semiconductor materials, optical materials, storage media, micromachines, biotechnology, and the environment.

  In some cases, it is necessary to transfer the pattern after aligning the material to be transferred and the mold. In Patent Document 1, the mold and the material to be transferred are provided with a convex portion and a concave portion to be fitted to each other. High-precision alignment is possible by pressing against the transfer material while pressing against the transfer material while guiding the mold with the inclined surfaces provided on the convex and concave portions, respectively.

Patent No. 4937500

  However, in the method of Patent Document 1, since the alignment of the mold with respect to the material to be transferred and the transfer of the concavo-convex pattern to the UV curable resin layer are performed simultaneously, depending on the fitting state of the convex and concave portions for alignment, Although the mold is pressed against the material to be transferred and the gap between the uneven pattern and the material to be transferred is very small and almost in contact, the mold moves relatively in the in-plane direction of the material to be transferred. May end up. If the mold is relatively moved in the in-plane direction of the transfer material while the gap between the uneven pattern and the transfer material is very small, the uneven pattern and the transfer material are rubbed, and the uneven pattern is scratched. Sometimes. When the concavo-convex pattern is scratched, there is a problem that the life of the mold is shortened.

  The present invention has been made in view of such circumstances, and provides a method for manufacturing a fine structure that enables highly accurate alignment between a transfer material and a mold while preventing damage to the mold. is there.

  According to the present invention, the transfer resin layer is cured in a state where the transfer pattern provided on the mold is pressed against the transfer resin layer obtained by applying the curable resin composition on the transfer material. A transfer step of transferring the transfer pattern onto the transfer resin layer, the transfer material including a transfer material side alignment pattern, the mold including a mold side alignment pattern, and the transfer Prior to the step, the mold is aligned with the transferred material by engaging the mold-side aligned pattern with the transferred material-side aligned pattern with the mold being bent. Provided is a method for manufacturing a microstructure including a process.

  In the present invention, before the transfer pattern is pressed against the transfer resin layer, the mold side alignment pattern is engaged with the transfer material side alignment pattern in a state in which the mold is curved, so that the mold is applied to the transfer material. Align. If alignment is performed by such a method, the alignment of the mold with respect to the transfer material is substantially completed by the time when the transfer pattern is pressed against the transfer resin layer and the gap between the transfer pattern and the transfer material becomes small. Therefore, when the gap between the transfer pattern and the transfer material is small, the mold does not substantially move relative to the transfer material in the in-plane direction. For this reason, according to the present invention, the transfer pattern is not scratched, and the transfer material and the mold can be aligned with high accuracy while preventing damage to the mold.

Hereinafter, various embodiments of the present invention will be exemplified. The embodiments described below can be combined with each other.
Preferably, the positioning step is performed so that the transfer pattern does not contact the transferred resin layer.
Preferably, the alignment step is performed such that the mold-side alignment pattern does not contact the transferred resin layer.
Preferably, the transferred material side alignment pattern and the mold side alignment pattern have complementary shapes.
Preferably, at least one of the mold side alignment pattern and the transfer material side alignment pattern has a tapered convex portion.
Preferably, the distance between the tip of the convex portion of the mold side alignment pattern and the back surface of the mold is longer than the distance between the tip of the convex portion of the transfer pattern and the back surface of the mold.
Preferably, the pitch of the mold side alignment pattern is larger than the pitch of the transfer pattern.
Preferably, the mold side alignment pattern has a square lattice arrangement.
Preferably, the curable resin composition is a photocurable resin composition that is cured by irradiation with active energy rays, and the mold includes a light shielding pattern that shields the active energy rays, and the light shielding pattern is used as a mask. The transfer resin layer is cured by irradiating the transfer resin layer with the active energy rays in an opening region provided in the light shielding pattern.
Preferably, after the transfer step, the mold is shifted to the next transfer position to perform the alignment step, and the transfer step is repeated at that position.

It is sectional drawing which shows the manufacturing method of the microstructure of 1st Embodiment of this invention. (A) is sectional drawing which shows the process of continuing from FIG. FIG. 5B is a cross-sectional view showing an alignment process in a state where the liquid resin layer 1 a exists between the alignment patterns 13 and 23. FIG. 3 is a cross-sectional view showing a step that follows from FIG. FIG. 4 is a cross-sectional view showing a process continued from FIG. 3. FIG. 5 is a cross-sectional view showing a process continued from FIG. 4. FIG. 6 is a cross-sectional view showing a process continued from FIG. 5. FIG. 7 is a cross-sectional view illustrating a process continued from FIG. 6. FIG. 8 is a cross-sectional view illustrating a process continued from FIG. 7. It is a top view which shows the state in which the some cured resin layer 2 was arranged in length and breadth. It is sectional drawing which shows the manufacturing method of the microstructure of 2nd Embodiment of this invention. It is sectional drawing which shows the process of continuing from FIG. FIG. 12 is a cross-sectional view showing a step continued from FIG. 11.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Various characteristic items shown in the following embodiments can be combined with each other. In addition, the invention is independently established for each feature.

1. 1st Embodiment The manufacturing method of the microstructure of 1st Embodiment of this invention is equipped with the to-be-transferred resin layer formation process, the alignment process, and the transcription | transfer process.

(1) Transferred Resin Layer Formation Step In this step, as shown in FIG. 1, the transfer resin layer 1 is formed by applying a curable resin composition on the transfer material 10.

  The transfer material 10 is provided with a transfer material side alignment pattern 13 used for alignment with the mold 20. The alignment pattern 13 may be provided on the entire surface of the transfer material 10 or may be provided only in an area necessary for alignment with the mold 20.

  For example, as shown in FIG. 1, the transfer material 10 includes a base material 11 and a resin layer 12 disposed thereon, and an alignment pattern 13 is formed on the resin layer 12.

  Examples of the material of the substrate 11 include resin, quartz, silicon, and the like, but it is preferable to use a resin from the viewpoint of forming a resin mold having flexibility, material cost, and flexibility. Specifically, the resin substrate is, for example, from one or a mixture of two or more selected from the group consisting of polyethylene terephthalate, polycarbonate, polyester, polyolefin, polyimide, polysulfone, polyethersulfone, cyclic polyolefin, and polyethylene naphthalate. It will be.

  The resin layer 12 can be formed by curing a curable resin composition. The curable resin composition is a curable resin composition, for example, a thermosetting resin composition or a photocurable resin composition. The photocurable resin composition contains a monomer and a photoinitiator and has a property of being cured by irradiation with active energy rays. “Active energy rays” is a general term for energy rays that can cure a photocurable resin composition, such as UV light, visible light, and electron beams.

  Monomers include photopolymerizable monomers for forming (meth) acrylic resins, styrene resins, olefin resins, polycarbonate resins, polyester resins, epoxy resins, silicone resins, etc., and photopolymerizable (meth) acrylic. System monomers are preferred. In the present specification, (meth) acryl means methacryl and / or acryl, and (meth) acrylate means methacrylate and / or acrylate.

  A photoinitiator is a component added in order to accelerate | stimulate superposition | polymerization of a monomer, and it is preferable to contain 0.1 mass part or more with respect to 100 mass parts of said monomers. Although the upper limit of content of a photoinitiator is not prescribed | regulated in particular, For example, it is 20 mass parts with respect to 100 mass parts of said monomers.

  The transferred resin layer 1 is formed by applying a liquid curable resin composition. The description of the curable resin composition is as described above. In FIG. 1, the curable resin composition is applied so as to cover the alignment pattern 13, but the alignment pattern 13 is not provided at a portion where the curable resin composition is applied. The transferred resin layer 1 may be formed by applying a curable resin composition on a flat surface. Further, the transferred resin layer 1 may be formed only in a region where the transfer pattern 24 of the mold 20 is transferred in the transfer step, or may be formed on the entire surface of the transferred material 10. The thickness of the transferred resin layer 1 is usually 50 nm to 1 mm, preferably 500 nm to 500 μm. With such a thickness, imprinting is easy to perform.

(2) Alignment step In this step, as shown in FIGS. 1 to 3, the alignment pattern 23 is engaged with the alignment pattern 13 in a state where the mold 20 is curved. To align the mold 20. The alignment step may be performed before the transferred resin layer forming step.

  The mold 20 is provided with an alignment pattern 23 used for alignment with the transfer material 10 and a transfer pattern 24 transferred to the transfer resin layer 1. The alignment pattern 23 and the transfer pattern 24 are provided at positions separated from each other. When the alignment pattern 23 is engaged with the alignment pattern 13 while the mold 20 is curved, the transfer pattern 24 is covered. It does not come into contact with the transfer material 10 (preferably so as not to come into contact with the transferred resin layer 1).

  The alignment patterns 13 and 23 can have any shape that can be engaged with each other, and preferably have a complementary shape. In this specification, as the form in which the alignment patterns 13 and 23 are engaged, in addition to the form in which the mutually complementary patterns are fitted, at least the non-complementary patterns as in the second embodiment are used. A form in which one surface abuts each other can be cited. As the alignment patterns 13 and 23, shapes such as pillars / holes, lines and spaces, and meshes can be adopted, and the alignment patterns 13 and 23 are preferably in a square lattice arrangement so as to be easily recognized as coordinates. . The alignment patterns 13 and 23 preferably have tapered convex portions 13a and 23a so that they can easily mesh with each other. Note that only one of the alignment patterns 13 and 23 may be provided with a tapered convex portion.

  The transfer pattern 24 is a pattern to be transferred to the resin layer 1 to be transferred, and the shape and pitch thereof are not particularly limited, and those having a period of 10 nm to 2 mm and a depth of 10 nm to 500 μm are preferable, and a period of 20 nm to 20 μm and a depth of The thing of 50 nm-1 micrometer is more preferable. Examples of the shape of the transfer pattern 24 include moth-eye, line, cylinder, monolith, cone, polygonal pyramid, and microlens.

  The pitch of the alignment patterns 13 and 23 is preferably larger than the pitch of the transfer pattern 24. Since the alignment patterns 13 and 23 can be easily engaged by increasing the pitch of the alignment patterns 13 and 23, the alignment can be performed without using a highly accurate stage. The pitch of the alignment patterns 13 and 23 is preferably 1 μm to 1 mm, and preferably 1 to 100 μm. In other words, the pitch of the alignment patterns 13 and 23 is preferably 2 to 100 times the pitch of the transfer pattern 24, and more preferably 5 to 50 times. The alignment patterns 13 and 23 and the transfer pattern 24 may be regular or irregular, but are preferably regular from the viewpoint of work efficiency. When these patterns are irregularly formed, the average value of the distances between the tips of the many convex portions constituting these patterns is defined as “pitch”.

  A distance D1 between the tip 23c of the protrusion 23a of the alignment pattern 23 and the back surface 26 of the mold 20 is longer than a distance D2 between the tip 24c of the protrusion 24a of the transfer pattern 24 and the back surface 26 of the mold 20. According to such a configuration, when the alignment patterns 13 and 23 are engaged, the gap between the transfer pattern 24 and the transfer material 10 is increased, and the friction between the transfer pattern 24 and the transfer material 10 is reduced. It can be prevented more effectively.

  For example, as shown in FIG. 1, the mold 20 includes a base material 21 and a resin layer 22 disposed thereon, and an alignment pattern 23 and a transfer pattern 24 are formed on the resin layer 22. .

  The substrate 21 is preferably a resin substrate. In this case, the mold 20 has flexibility, and the mold 20 can be easily bent in the alignment step. Specific examples of the resin base material are as listed in the description of the base material 11. The resin layer 12 can be formed by curing a curable resin composition. The description of the curable resin composition is as described above.

  In the present embodiment, the alignment patterns 13 and 23 are engaged with each other (more specifically, the protrusions 23 a of the alignment pattern 23 enter the recesses 13 d between the adjacent protrusions 13 a of the alignment pattern 13. Is fitted). As shown in FIG. 2A, when the center position of the convex portion 23a is shifted from the center position of the concave portion 13d, the inclined surface 23b of the convex portion 23a and the inclined surface 13b of the convex portion 13a are in contact with each other. When the mold 20 is pushed into the transfer material 10, the mold 20 moves relative to the transfer material 10 so as to be guided by the inclined surfaces 13b and 23b. As shown in FIG. The part 23a fits into the recess 13d, and the alignment process is completed. In this alignment step, when the mold 20 is guided and moved by the inclined surfaces 13b and 23b, the mold 20 approaches the transfer material 10 and also moves in the in-plane direction. In this embodiment, the transfer pattern 24 is Since the transfer pattern 24 is located away from the transfer material 10, the transfer pattern 24 does not rub against the transfer material 10 as the mold 20 moves in the plane. In order to reliably prevent rubbing between the transfer pattern 24 and the transfer material 10, it is preferable that the transfer pattern 24 is sufficiently separated from the transfer material 10, and the transfer pattern 24 is transferred to the transfer resin layer in the alignment step. 1 is preferably not in contact.

  Further, in the present embodiment, it is preferable that the alignment step is performed so that the alignment pattern 23 does not contact the transferred resin layer 1. If the curable resin composition enters between the alignment patterns 13 and 23, the alignment accuracy may be reduced by that amount, but at a position away from the transferred resin layer 1 as in this embodiment. By engaging the alignment pattern 23 with the alignment pattern 13, it is possible to suppress a decrease in alignment accuracy. However, from another viewpoint, as shown in FIG. 2B, by bringing the alignment resin pattern 13 and 23 into contact with each other in the state where the liquid resin 1a exists between the alignment patterns 13 and 23, friction is caused. Since it is possible to prevent the alignment patterns 13 and 23 from being damaged, it is also preferable to perform the alignment process in a state where the liquid resin 1a exists between the alignment patterns 13 and 23. The liquid resin 1a may be the same as the above-described curable resin composition, or may be a liquid resin having no curability.

(3) Transfer process In this process, as shown in FIG. 4, the transferred resin layer 1 is cured while pressing the transfer pattern 24 provided on the mold 20 against the transferred resin layer 1. The transfer pattern 24 is transferred to the transferred resin layer 1. Thereby, as shown in FIG. 5, the cured resin layer 2 having the uneven pattern 24 r is formed on the transfer material 10. The concave / convex pattern 24 r is a reverse pattern of the transfer pattern 24.

  In the above alignment step, the mold 20 is aligned with the material to be transferred 10, and from this state, the curved mold 20 is returned to the original state, and the transfer pattern 24 is transferred to the resin layer 1 to be transferred. The transfer pattern 24 can be transferred to a position aligned with high accuracy by pressing the pattern onto the position. In one example, the transfer pattern 24 can be transferred to the transferred resin layer 1 by pressing the mold 20 against the transfer material 10 with the roller while moving the roller on the mold 20.

  In this embodiment, the transferred resin layer 1 is made of a photocurable resin composition, and the mold 20 is provided with a light shielding pattern 25 that shields the active energy rays 30. As shown in FIGS. 1 and 4, the light shielding pattern 25 is provided with an opening region R, and the light shielding pattern 25 is irradiated by irradiating the transfer resin layer 1 with the active energy ray 30 using the light shielding pattern 25 as a mask. The resin layer 1 to be transferred can be cured in the opening region R provided on the substrate. Thereafter, the mold 20 is detached from the transferred resin layer 1, and the uncured portion of the transferred resin layer 1 is rinsed and removed, whereby the cured resin layer 2 having the uneven pattern 24r is applied as shown in FIG. It can be formed on the transfer material 10. Instead of using the mold 20 having the light shielding pattern 25, the transferred resin layer 1 may be cured at a portion corresponding to the opening region R using another member having the light shielding pattern as a mask.

(4) Step-and-repeat type imprint The manufacture of the fine structure in which the concave / convex pattern 24r is formed at the position aligned with high accuracy by the configuration of (1) to (3) above is completed. In this fine structure, the region where the concave / convex pattern 24r is formed is the same size as the opening region R. By performing step-and-repeat imprinting by repeating the steps (1) to (3) by shifting the position 20, the region where the concave / convex pattern 24 r is formed can be expanded.

  In this embodiment, as shown in FIG. 6, a new transferred resin layer 1 is formed at a position adjacent to the cured resin layer 2, and the mold 20 is shifted by one pitch of the alignment patterns 13 and 23. After aligning the mold 20 with respect to the transfer material 10, as shown in FIG. 7, the transfer pattern 24 is pressed against the transfer resin layer 1 to cure the transfer resin layer 1. As shown in FIG. 8, a new cured resin layer 2 having a concavo-convex pattern 24r can be formed at a position adjacent to the cured resin layer 2 formed in the step (3).

  By repeating such steps, a microstructure having a plurality of cured resin layers 2 arranged at a pitch P1 can be produced as shown in FIGS. By matching the pitch P1 with the width W of the opening region R, the cured resin layers 2 formed in a plurality of steps can be arranged adjacent to each other without any gap. The same effect can be obtained by making n times the pitch P1 (n is an integer of 2 or more) coincide with the width W of the opening region R and moving the position of the mold 20 by n pitches every step. It is done.

  The order in which step-and-repeat is performed is not particularly limited, and after the plurality of cured resin layers 29 in FIG. 9 are formed in order from right to left, the second and third cured resin layers are formed. 29 may be formed, and after the plurality of cured resin layers 29 in the rightmost row in FIG. 9 are formed in order from the top to the bottom, the cured resin layers 29 in the second and subsequent rows from the right may be formed. Other orders may also be formed. In FIG. 9, the vertical and horizontal pitches are both P1, but the vertical and horizontal pitches may be different from each other. In FIG. 9, the plurality of cured resin layers 2 are two-dimensionally arranged, but may be arranged one-dimensionally. In FIG. 9, the cured resin layer 2 formed in each step has a square shape, but the shape of the cured resin layer 2 can be changed by changing the shape of the opening region R.

  The microstructure obtained by the method of the present embodiment includes an imprint mold, a microcontact print stamper, an optical sheet (an antireflection sheet, a hologram sheet, a lens sheet, a polarization separation sheet), a water repellent sheet, and a hydrophilic sheet cell. It can be used for culture sheets.

The present invention can also be implemented in the following forms.
-The number of the convex parts 23a of the alignment pattern 23 is not specifically limited, Any of 1, 2, 3, 4 or more may be sufficient. In order to align the mold 20 with respect to the transfer material 10 in a one-dimensional manner, the required number of the convex portions 23a is one. In order to align the mold 20 with respect to the transfer material 10 in two dimensions, the required number of the convex portions 23a is two. From the viewpoint of preventing damage to the convex portions 23a, it is preferable that the number of the convex portions 23a is large.
The shape of the convex portions 13a and 23a is preferably a shape in which the inclined surfaces of the convex portions 13a and 23a continue to the tips of the convex portions 13a and 23a from the viewpoint of facilitating alignment. Examples of such a shape include a conical shape, a polygonal pyramid (eg, quadrangular pyramid) shape, and a hemispherical shape.

2. Second Embodiment A method for manufacturing a microstructure according to a second embodiment of the present invention will be described with reference to FIGS. The present embodiment is similar to the first embodiment, and the main difference is that the shape of the alignment pattern 13 is different. Hereinafter, the difference will be mainly described.

  In the present embodiment, as shown in FIG. 10, the alignment patterns 13 and 23 are not in a complementary shape. Therefore, as shown in FIG. 11, even if the mold 20 is pressed against the material to be transferred 10, the tip 23 c of the convex portion 23 a of the alignment pattern 23 is brought into contact with the bottom 13 e of the alignment pattern 13. , It is not aligned with the transfer material 10. However, the mold 20 is moved in the in-plane direction (arrow X direction) of the transfer material 10 from the state shown in FIG. 11, and the inclined surface 23b of the convex portion 23a of the alignment pattern 23 is positioned as shown in FIG. By engaging (more specifically, contacting) the inclined surface 13 b of the convex portion 13 a of the alignment pattern 13, the mold 20 can be aligned with the transfer material 11. According to this embodiment, if the mold 20 is aligned with the transfer material 10 to such an extent that the protrusions 23a can be inserted between the adjacent protrusions 13a, highly accurate alignment is possible. Even when a device with lower accuracy than that of the first embodiment is used, highly accurate alignment is possible. However, in this embodiment, it is preferable to provide a mechanism for pressing and holding the mold 20 in the direction of the arrow X so that the mold 20 is not displaced relative to the transfer material 10 after the alignment step.

  Also in the present embodiment, in the alignment step, the mold 20 is curved and the transfer pattern 24 is not in contact with the material to be transferred 10, so the mold 20 is placed in the in-plane direction of the material to be transferred 10. Even if moved, the transfer pattern 24 is not scratched.

The present invention can also be implemented in the following forms.
-Instead of the side surfaces of the convex portions 13a, 13b being inclined surfaces 13b, 23b, they may be substantially perpendicular to the base materials 11, 21. In this case, the convex portions 13a and 13b can be formed in a columnar shape or a polygonal column (square column) shape.

1: transferred resin layer, 2: cured resin layer, 10: transferred material, 11: substrate, 12: resin layer, 13: alignment pattern, 20: mold, 21: substrate, 22: resin layer, 23 : Positioning pattern, 24: Transfer pattern, 25: Light shielding pattern

Claims (10)

The transfer pattern is obtained by curing the transfer resin layer in a state where the transfer pattern provided on the mold is pressed against the transfer resin layer obtained by applying the curable resin composition on the transfer material. A transfer step of transferring the image to the transferred resin layer,
The transfer material includes a transfer material side alignment pattern,
The mold includes a mold side alignment pattern,
Prior to the transfer step, the mold is aligned with the transfer material by engaging the mold-side alignment pattern with the transfer material-side alignment pattern in a state where the mold is curved. A manufacturing method of a fine structure provided with an alignment process. The method for manufacturing a microstructure according to claim 1, wherein the alignment step is performed so that the transfer pattern does not contact the transferred resin layer. 3. The method for manufacturing a microstructure according to claim 1, wherein the alignment step is performed such that the mold-side alignment pattern does not contact the transferred resin layer. The method for manufacturing a microstructure according to any one of claims 1 to 3, wherein the transfer material side alignment pattern and the mold side alignment pattern have complementary shapes. 5. The method for manufacturing a microstructure according to claim 1, wherein at least one of the mold side alignment pattern and the transfer material side alignment pattern has a tapered convex portion. The distance between the tip of the convex portion of the mold side alignment pattern and the back surface of the mold is longer than the distance between the tip of the convex portion of the transfer pattern and the back surface of the mold. The manufacturing method of the microstructure as described in any one of these. The pitch of the said mold side alignment pattern is a manufacturing method of the microstructure as described in any one of Claims 1-6 larger than the pitch of the said transfer pattern. The method for manufacturing a microstructure according to any one of claims 1 to 7, wherein the mold side alignment pattern has a square lattice arrangement. The curable resin composition is a photocurable resin composition that is cured by irradiation with active energy rays,
The mold includes a light shielding pattern that shields the active energy ray,
The transferred resin layer is cured in an opening region provided in the light shielding pattern by irradiating the transferred energy layer with the active energy ray using the light shielding pattern as a mask. The manufacturing method of the fine structure as described in any one. The fine pattern according to any one of claims 1 to 9, wherein after the transfer step, the mold is shifted to a next transfer position, the alignment step is performed, and the transfer step is repeated at that position. Manufacturing method of structure.