JP2019145578A - Blank backing material, imprint mold, manufacturing method of imprint mold and imprint method - Google Patents

Abstract

To provide an imprint mold capable of restraining squeeze-out of imprint resin from the irregularity patterning region of a convex structure part to the outside, and to provide a blank backing material used for production thereof, a production method of the imprint mold and an imprint method.SOLUTION: A blank backing material includes a proximal region having a first face and a second face facing the first face, and a third face where a functional region, surrounding the outside of a pattern region set on the first face, is set, and an irregular structure part for contact angle adjustment formed on the third face. The third face has an inner peripheral edge part continuous to the outer marginal part of the first face, and an outer peripheral edge part located closer to the second face side than the inner peripheral edge part, and the irregular structure part for contact angle adjustment has an uneven direction substantially orthogonal to the first face.SELECTED DRAWING: Figure 2

Description

  The present disclosure relates to a blanks substrate, an imprint mold, a manufacturing method thereof, and an imprint method.

  Nanoimprint technology, known as microfabrication technology, uses an imprint mold in which a fine concavo-convex pattern is formed on the surface of a substrate, and the fine concavo-convex pattern is transferred to the workpiece by magnifying the fine concavo-convex pattern. This is a pattern forming technique for transferring. In particular, with further miniaturization of wiring patterns and the like in semiconductor devices, nanoimprint technology has attracted attention in its manufacturing process and the like.

  As an imprint mold generally used in the nanoimprint technology, for example, a mold including a base material, a convex structure portion protruding from the surface of the base material, and a fine concavo-convex pattern formed on the upper surface of the convex structure portion is known. ing. By using such an imprint mold, the imprint resin as the workpiece supplied on the transfer substrate is brought into contact with the fine uneven pattern of the imprint mold, so that the imprint resin is filled into the fine uneven pattern. . Then, by curing the imprint resin in this state, a pattern structure formed by transferring the fine uneven pattern of the imprint mold is formed.

  If the supply amount of the imprint resin is insufficient, the fine uneven pattern is not sufficiently filled with the imprint resin, and a defect (unfilled defect) is generated in the pattern structure. On the other hand, it is extremely difficult to control the supply amount of the imprint resin with high accuracy. If an imprint resin is supplied to the substrate to be transferred in a sufficient amount so as not to cause an unfilled defect, when the imprint mold is brought into contact with the imprint resin, excess imprint resin is formed outside the convex structure portion of the imprint mold. The print resin protrudes and adheres to the side surface of the convex structure portion. The imprint resin that protrudes outside the convex structure and adheres to the side surface is cured simultaneously with the imprint resin filled in the fine uneven pattern. As a result, when the imprint mold is pulled away from the imprint resin, a large stress acts, which may cause damage to the imprint mold and the pattern structure. In addition, when imprint processing is performed by a so-called step-and-repeat method, it is necessary to separate the imprinted region so that it does not overlap the cured imprint resin that protrudes outside the convex structure portion. The number of times that the imprint process can be performed on the transfer substrate is limited.

  In order to solve such a problem, an imprint mold in which a highly liquid-repellent portion or the like is provided on the side surface of the convex structure portion so as to surround the outer periphery of the pattern region where the fine concavo-convex pattern is formed is conventionally known. (See Patent Document 1).

JP, 2006-157785, A

  In the imprint mold described in Patent Document 1, the side surface of the convex structure portion is provided with a highly liquid-repellent portion made of a concavo-convex structure or a liquid-repellent coating, and the imprint resin from the pattern region during imprint processing Can be prevented from protruding. However, when multiple imprints are continuously performed using an imprint mold provided with a highly liquid-repellent part made of a liquid-repellent film, the liquid-repellent film gradually peels off and the liquid repellency deteriorates. There is a risk of it. In addition, the concavo-convex structure as a highly liquid repellent portion provided on the side surface of the convex structure portion has a concavo-convex direction orthogonal to the side surface. Unlike the liquid-repellent coating, this concave-convex structure is excellent in that the liquid repellency is not deteriorated by imprinting multiple times, but the concave-convex direction perpendicular to the side surface of the convex structure is set. It is extremely difficult to form the concavo-convex structure having high accuracy. Therefore, even in the imprint mold described in Patent Document 1, the imprint resin may still largely protrude outside the pattern region.

  In view of the above problems, the present disclosure is directed to an imprint mold capable of suppressing the protrusion of an imprint resin to the outside from a concavo-convex pattern forming region of a convex structure portion, a blank base material used for manufacturing the imprint resin, and the imprint An object is to provide a method for producing a print mold and an imprint method.

  In order to solve the above problems, as an embodiment of the present disclosure, a functional area surrounding the first surface, the second surface facing the first surface, and the outside of the pattern region set on the first surface is provided. A base portion having a third surface to be set; and a contact angle adjusting concavo-convex structure portion formed on the third surface, wherein the third surface is an inner peripheral edge portion continuous with an outer edge portion of the first surface. And an outer peripheral edge portion located closer to the second surface than the inner peripheral edge portion, and the contact angle adjusting uneven structure portion has an uneven direction substantially orthogonal to the first surface. A blanks substrate is provided.

  The third surface only needs to include a first inclined surface having a first inclination angle and a second inclined surface having a second inclination angle different from the first inclination angle, and the first inclination angle. However, it may be larger than the second inclination angle, and the first inclination angle may be smaller than the second inclination angle.

  The third surface may include a concave curved surface that is concave toward the second surface, or may include a convex curved surface that is convex toward the first surface. The third surface may be an inclined surface that is inclined from the inner peripheral edge toward the outer peripheral edge.

  The concave width on the third surface side of the concave portion of the concave structure for contact angle adjustment may be larger than the concave width at the bottom portion of the concave portion, and the concave width of the concave portion of the concave structure for contact angle adjustment may be You may gradually reduce toward the said bottom part from 3 surface side. Moreover, the concave width of the concave portion of the concave-convex structure for contact angle adjustment may be substantially the same in the depth direction of the concave portion.

  The difference in height between the inner peripheral edge and the outer peripheral edge in the thickness direction of the base may be 100 μm or less, and may further include a light shielding film that covers at least the third surface. .

  As one embodiment of the present disclosure, an imprint mold having a concavo-convex pattern formed in the pattern region of the blank base material is provided.

  As one embodiment of the present disclosure, a method of manufacturing the imprint mold, the step of forming a mask pattern corresponding to the uneven pattern in the pattern region of the blank base material, and the mask pattern is formed. In addition, a method of manufacturing an imprint mold is provided that includes etching the blank base material to form the concavo-convex pattern.

  As one embodiment of the present disclosure, an imprint method using the imprint mold includes a transfer surface having wettability different from wettability to the imprint resin of the third surface of the imprint mold. Preparing the substrate to be transferred, supplying the imprint resin to the surface to be transferred, bringing the concave / convex pattern into contact with the imprint resin on the surface to be transferred; There is provided an imprint method including a step of transferring a concavo-convex pattern and a step of separating the imprint mold from the imprint resin having the concavo-convex pattern transferred thereto.

  The contact angle of the third surface to the imprint resin may be larger than the contact angle of the transferred surface to the imprint resin, or smaller than the contact angle of the transferred surface to the imprint resin. Also good.

  The contact angle of the third surface with respect to the imprint resin can be made larger than the contact angle of the first surface with respect to the imprint resin. If the contact angle of the third surface is smaller than the contact angle of the first surface and the inclination angle of the third surface is small, the capillary force acting on the narrow space between the transferred surface and the third surface is combined. Although there is a possibility that the imprint resin protrudes easily, the protrusion of the imprint resin can be suppressed because the contact angle of the third surface is larger than the contact angle of the first surface.

  According to the present disclosure, an imprint mold capable of suppressing the protrusion of the imprint resin from the concavo-convex pattern forming region of the convex structure portion to the outside, the blank base material used for manufacturing the imprint resin, and the manufacture of the imprint mold A method and an imprint method can be provided.

FIG. 1 is a cut end view illustrating a schematic configuration of an aspect of a blank base material according to an embodiment of the present disclosure. FIG. 2 is a partially enlarged cut end view showing a schematic configuration of a part A in FIG. FIG. 3 is a partially enlarged cut end view showing a schematic configuration of a portion B in FIG. FIG. 4 is a partially enlarged cut end view (part 1) illustrating an operation of the uneven structure for contact angle adjustment according to an embodiment of the present disclosure. FIG. 5 is a partially enlarged cut end view (part 2) illustrating an operation of the uneven structure for contact angle adjustment according to an embodiment of the present disclosure. FIG. 6 is a partially enlarged cut end view (part 3) illustrating the operation of the contact angle adjusting uneven structure according to the embodiment of the present disclosure. FIG. 7 is a partially enlarged cut end view illustrating a schematic configuration of another aspect (part 1) of the inclined surface of the blank base material according to the embodiment of the present disclosure. FIG. 8 is a partial enlarged cut end view illustrating a schematic configuration of another aspect (part 2) of the inclined surface of the blank base material according to the embodiment of the present disclosure. FIG. 9 is a partially enlarged cut end view illustrating a schematic configuration of another aspect (part 3) of the inclined surface of the blank base material according to the embodiment of the present disclosure. FIG. 10 is a partially enlarged cut end view illustrating a schematic configuration of another aspect (part 4) of the inclined surface of the blank base material according to the embodiment of the present disclosure. FIG. 11 is a partial enlarged cut end view illustrating a schematic configuration of another aspect (No. 5) of the inclined surface of the blank base material according to the embodiment of the present disclosure. FIG. 12 is a partial enlarged cut end view illustrating a schematic configuration of another aspect (No. 6) of the inclined surface of the blank base material according to the embodiment of the present disclosure. FIG. 13 is a partial enlarged cut end view illustrating a schematic configuration of another aspect (part 7) of the inclined surface of the blank base material according to the embodiment of the present disclosure. FIG. 14 is a plan view illustrating a schematic configuration of a blank base material according to an embodiment of the present disclosure. FIG. 15 is a cut end view illustrating a schematic configuration of an imprint mold according to an embodiment of the present disclosure. FIG. 16 is a partially enlarged cut end view schematically showing one step of the blanks substrate manufacturing method according to an embodiment of the present disclosure. FIG. 17 is a partial enlarged cut end view schematically illustrating a process subsequent to the process illustrated in FIG. 16, which is a process of the blanks substrate manufacturing method according to the embodiment of the present disclosure. FIG. 18 is a partial enlarged cut end view schematically illustrating a process subsequent to the process illustrated in FIG. 17, which is a process of the blanks substrate manufacturing method according to the embodiment of the present disclosure. FIG. 19 is a partial enlarged cut end view schematically illustrating a process subsequent to the process illustrated in FIG. 18, which is a process of the blanks substrate manufacturing method according to the embodiment of the present disclosure. FIG. 20 is a partial enlarged cut end view schematically illustrating a process subsequent to the process illustrated in FIG. 19, which is a process of the blanks substrate manufacturing method according to the embodiment of the present disclosure. FIG. 21 is a partial enlarged cut end view schematically illustrating a process subsequent to the process illustrated in FIG. 20, which is a process of the blanks substrate manufacturing method according to the embodiment of the present disclosure. FIG. 22 is a process flow diagram illustrating each process of the imprint method according to an embodiment of the present disclosure on a cut end surface. FIG. 23 is a process flow diagram showing each process of the imprint method according to an embodiment of the present disclosure, and showing a process subsequent to the process shown in FIG. FIG. 24 is a cut end view illustrating a schematic configuration of a blank base material according to another embodiment of the present disclosure.

Embodiments of the present disclosure will be described with reference to the drawings.
In the drawing, in order to facilitate understanding, the shape, scale, vertical / horizontal dimension ratio, etc. of each part may be changed from the actual one or may be exaggerated. In the present specification and the like, a numerical range expressed using “to” means a range including each of the numerical values described before and after “to” as a lower limit value and an upper limit value. In this specification and the like, terms such as “film”, “sheet”, and “plate” are not distinguished from each other on the basis of the difference in names. For example, the “plate” is a concept including members that can be generally called “sheet” and “film”.

[Blanks substrate]
FIG. 1 is a cut end view showing a schematic configuration of one aspect of a blanks substrate according to the present embodiment, and FIG. 2 is a partially enlarged cut end view showing a schematic configuration of part A in FIG. FIG. 3 is a partially enlarged cut end view showing a schematic configuration of a portion B in FIG. 2.

  As shown in FIGS. 1-3, the blanks base material 1 which concerns on this embodiment is the base 2 which has the surface 2A and the back surface 2B which opposes the said surface 2A, and the convex structure part 3 which protrudes from the surface 2A of the base 2. And a recess 4 formed on the back surface 2B side.

  As the base 2, a general substrate for imprint molding, for example, a quartz glass substrate, a soda glass substrate, a fluorite substrate, a calcium fluoride substrate, a magnesium fluoride substrate, a barium borosilicate glass, an aminoborosilicate glass, A glass substrate such as an alkali-free glass substrate such as aluminosilicate glass, a polycarbonate substrate, a polypropylene substrate, a polyethylene substrate, a polymethyl methacrylate substrate, a resin substrate such as a polyethylene terephthalate substrate, and two or more substrates arbitrarily selected from these substrates A transparent substrate such as a laminated substrate formed by lamination can be used. In the present embodiment, “transparent” means that light having a wavelength capable of curing the imprint resin can be transmitted, and the transmittance of light having a wavelength of 150 nm to 400 nm is 60% or more. Preferably, it is 90% or more, particularly preferably 95% or more.

  The shape of the base 2 in plan view is not particularly limited, and examples thereof include a substantially rectangular shape and a substantially circular shape. When the base 2 is made of a quartz glass substrate that is generally used for optical imprinting, the shape of the base 2 in a plan view is usually a substantially rectangular shape.

  The size of the base 2 (size in plan view) is not particularly limited, but when the base 2 is made of the quartz glass substrate, for example, the size of the base 2 is about 152 mm × 152 mm. In addition, the thickness of the base portion 2 can be set as appropriate within a range of, for example, about 300 μm to 10 mm in consideration of strength, suitability for handling, and the like.

  The convex structure portion 3 protruding from the surface 2A of the base portion 2 is provided at substantially the center of the base portion 2 in plan view. The shape of the convex structure 3 in plan view may be, for example, a substantially rectangular shape, but is not limited thereto, and may be any polygonal shape such as a substantially octagonal shape, a substantially circular shape, or a substantially elliptical shape. It may be a shape. The size of the convex structure portion 3 is appropriately set according to a product or the like manufactured through imprint processing using the imprint mold 10 (see FIG. 15), and is approximately 33 mm × 26 mm, for example. The rectangular convex structure part 3 can be mentioned.

  The protruding height of the convex structure portion 3 (the length along the thickness direction of the base portion 2 between the surface 2A of the base portion 2 and the upper surface 31 of the convex structure portion 3) is the imprint mold 10 in this embodiment (see FIG. 15). ) Is not particularly limited as long as it can serve the purpose of providing the convex structure portion 3, and can be set to about 10 μm to 100 μm, for example.

  The convex structure portion 3 includes an upper surface 31 having a pattern area PA on which the concave / convex pattern 11 (see FIG. 15) is to be formed, an inner peripheral edge portion 32A continuous to the edge portion of the upper surface 31, and a back surface from the inner peripheral edge portion 32A. An inclined surface 32 having an outer peripheral edge portion 32B located on the 2B side, and a side surface that is continuous with the outer peripheral edge portion 32B of the inclined surface 32 and is substantially orthogonal to the upper surface 31 (substantially parallel to the thickness direction of the base portion 2). 33.

  The width W32 of the inclined surface 32 (the length between the inner peripheral edge portion 32A and the outer peripheral edge portion 32B in plan view from the surface 2A side) is not particularly limited, but may be, for example, about 50 μm to 700 μm. The thickness is preferably about 100 μm to 500 μm. As will be described later, in the imprint mold 10 manufactured from the blanks substrate 1 according to the present embodiment, the imprint resin 81 from the pattern region PA is formed by the contact angle adjusting uneven structure 5 formed on the inclined surface 32. Although the protrusion can be suppressed, if the width W32 of the inclined surface 32 is less than 50 μm, the desired resin protrusion suppression effect by the contact angle adjusting uneven structure 5 of the inclined surface 32 may not be obtained.

  The height T32 of the inclined surface 32 (the difference in height position between the inner peripheral edge portion 32A and the outer peripheral edge portion 32B in the thickness direction of the base portion 2) is not particularly limited, and is preferably about 100 μm or less, for example. May be 50 μm or less. When the height T32 of the inclined surface 32 exceeds 100 μm, it is difficult to control the dimensions when forming the contact angle adjusting concavo-convex structure 5 to be described later, and the desired resin protrusion suppression effect may not be obtained.

  On the inclined surface 32, the contact angle adjusting concavo-convex structure 5 having the concave portion 51 and the convex portion 52 is formed. The contact angle adjusting concavo-convex structure 5 can adjust the contact angle with respect to the imprint resin to an arbitrary value by a so-called Lotus effect. In the present embodiment, the uneven structure 5 for adjusting the contact angle is exemplified as an example formed on the entire surface of the inclined surface 32 (between the inner peripheral edge portion 32A and the outer peripheral edge portion 32B) (see FIG. 2). ), But is not limited to this embodiment. In the imprint mold 10 manufactured from the blanks substrate 1 according to the present embodiment, the contact angle adjusting concavo-convex structure 5 in the present embodiment is a pattern region formed by the contact angle adjusting concavo-convex structure 5 formed on the inclined surface 32. As long as the protrusion of the imprint resin 81 from the PA can be suppressed, the imprint resin 81 may be formed on a part of the inclined surface 32 from the inner peripheral edge portion 32A toward the outer side (the outer peripheral edge portion 32B side in a plan view). .

  The contact angle θ5 of the concavo-convex structure 5 for adjusting the contact angle with respect to the imprint resin used during the imprint process using the imprint mold 10 (see FIG. 15) manufactured from the blanks substrate 1 according to the present embodiment is the imprint The contact angle θ80 with respect to the imprint resin of the transferred substrate 80 (see FIG. 22A) used during the printing process may be larger or smaller. For example, the difference between the contact angle θ80 of the transferred substrate 80 with respect to the imprint resin and the contact angle θ5 of the uneven structure 5 for adjusting the contact angle with respect to the imprint resin may be 2 ° or more, preferably 4 ° or more. Good. The contact angle is measured, for example, by dropping the imprint resin on the surface of the liquid-repellent uneven structure 5 using a microsyringe under the conditions of a temperature of 25 ° C. and a humidity (RH) of 30%, and then measuring the contact angle 10 seconds later. It can be measured using an apparatus (manufactured by Kyowa Interface Chemical Co., Ltd., automatic contact angle meter DM-501).

  Examples of the transfer target substrate 80 to be imprinted using the imprint mold 10 include a quartz glass substrate and a silicon wafer. Usually, the transfer surface of the transfer substrate 80 is provided with an adhesion layer for improving adhesion to the imprint resin, a contact angle adjusting layer for improving the ease of spreading of the imprint resin, and the like. The contact angle of the transferred surface with respect to the imprint resin is about 50 ° or less, preferably about 10 ° to 40 °, particularly preferably about 20 ° to 30 °.

  Further, when the contact angle θ5 of the contact angle adjusting concavo-convex structure 5 is smaller than the contact angle θ80 of the transfer substrate 80, as shown in FIG. 5, the imprint resin 81 protruding outward from the pattern area PA is transferred to the transfer substrate. It is easier to spread out along the inclined surface 32 (concave structure 5 for contact angle adjustment) than 80. Therefore, since the imprint resin that protrudes outward from the pattern area PA is pulled toward the inclined surface 32 side, the imprint resin is less likely to protrude from the state shown in FIG. 4 on the transfer substrate 80 side (the broken line in FIG. In the state shown, the outer edge of the region where the imprint resin 81 wets and spreads along each of the inclined surface 32 (concave structure 5 for adjusting the contact angle) and the transferred substrate 80 is shown. Further, since the imprint resin 81 wets and spreads outward along the inclined surface 32, the amount of the imprint resin that protrudes from the pattern area PA on the transfer substrate 80 can be reduced. As a result, the protrusion of the imprint resin 81 can be suppressed.

  Furthermore, if the contact angle θ5 of the contact angle adjusting concavo-convex structure 5 is larger than the contact angle θ80 of the transferred substrate 80, the imprint resin 81 hardly spreads along the inclined surface 32 as shown in FIG. The imprint resin 81 is pulled toward the pattern area PA on each of the inclined surface 32 side and the transfer substrate 80 side. As a result, the protrusion of the imprint resin 81 can be suppressed.

  The dimensions of the concave portions 51 and the convex portions 52 of the contact angle adjusting concavo-convex structure 5 (dimensions on the inclined surface 32 when viewed along the direction perpendicular to the upper surface 31 of the blanks substrate 1) are as follows. As long as the contact angle θ5 with respect to the imprint resin is larger than or smaller than the contact angle θ80 with respect to the imprint resin of the substrate to be transferred 80, it is not particularly limited. The dimension of the recess 51 means the length of one side when the recess 51 has a square hole shape, and the diameter when the recess 51 has a circular hole shape. In the case of a shape, the length in the short direction is meant.

For example, when the uneven structure 5 for adjusting the contact angle is not formed on the same substrate as the substrate constituting the base 2, the contact angle of the substrate with respect to the imprint resin is θs, the imprint atmosphere (gas), and the imprint resin When the contact angle with 81 is θg and the area density of the recesses 51 of the contact angle adjusting concavo-convex structure 5 is Rs, the contact angle θ5 between the inclined surface 32 on which the contact angle adjusting concavo-convex structure 5 is formed and the implied resin. Using the Cassie equation,
cos θ5 = (1−Rs) cos θs + Rs · cos θg
Rs <1
It is expressed. The area density Rs of the recesses 51 of the contact angle adjusting concavo-convex structure 5 is set so that the contact angle θ5 differs from the contact angle θ80 with respect to the imprint resin of the transfer substrate 80 (so as to be larger or smaller than the contact angle θ80). Should be set.

For example, when the concave portion 51 of the concave-convex structure for contact angle adjustment 5 has a square hole shape in plan view, when the length of one side of the hole of the concave portion 51 in plan view is Ws and the pitch of the concave portions 51 is Wp, the above formula Is
cos θ5 = ((Wp ² −Ws ² ) / Wp ² ) · cos θs + (Ws ² / Wp ² ) · cos θg
It becomes.
Further, when the recess 51 has a space shape, when the width in the short direction in a plan view is Ws and the pitch of the recess 51 is Wp, the above formula is
cos θ5 = ((Wp−Ws) / Wp) · cos θs + (Ws / Wp) · cos θg
It becomes.
Further, when the recess 51 has a circular hole shape in plan view, when the radius of the hole of the recess 51 in plan view is Wr and the pitch of the recess 51 is Wp, the above equation is
cos θ5 = ((Wp ² −πWr ² ) / Wp ² ) · cos θs + (πWr ² / Wp ² ) · cos θg
It becomes.
Therefore, the dimensions of the recesses 51 and the pitches of the recesses 51 may be set so as to satisfy the above formula according to the shape of the recesses 51.

  The depth direction of the concave portion 51 of the contact angle adjusting concave-convex structure 5 is preferably substantially perpendicular to the upper surface 31 of the convex structure portion 3. When the depth direction of the recessed portion 51 is perpendicular to the inclined surface 32, the imprint mold 10 is separated when a part of the imprint resin that spreads along the inclined surface 32 enters the recessed portion 51 and is cured. There is a possibility that the mold becomes difficult, or a stress is applied to the contact angle adjusting concavo-convex structure 5 when the imprint mold 10 is released to cause a defect. However, since the depth direction of the concave portion 51 is substantially perpendicular to the upper surface 31 of the convex structure portion 3, it is possible to suppress the occurrence of the above problem. The substantially vertical direction means that the angle formed by the depth direction of the concave portion 51 with respect to the upper surface 31 of the convex structure portion 3 is 90 ° ± 2 °.

As shown in FIG. 2, the inclined surface 32 in the present embodiment may be a surface having a predetermined inclination angle with respect to the upper surface 31 of the convex structure portion 3, but as shown in FIG. 7, It may be configured by a convex curved surface (convex curved surface) toward the front surface 2A, or may be configured by a concave curved surface (concave curved surface) toward the back surface 2B of the base 2 as shown in FIG. May be. The inclined surface 32 includes a first inclined surface 321 having a first inclination angle and a second inclined surface 322 having a second inclination angle, and the first inclination angle may be smaller than the second inclination angle. However, it may be larger than the second inclination angle (see FIG. 10). Furthermore, you may be comprised by the surface and the curved surface (concave curved surface or convex curved surface) which have a predetermined inclination angle. When at least a part of the inclined surface 32 is a curved surface (concave curved surface or convex curved surface), the size and pitch of the concave portions 51 are determined by the contact angle θ5 with respect to the imprint resin of the concave / convex structure for contact angle adjustment 5. Any size and pitch that can be larger or smaller than the contact angle θ80 of the transfer substrate 80 to the imprint resin may be used. Since the following formula according to the shape of the recess 51 described above is established on the assumption that the inclined surface 32 is a flat surface, when at least a part of the inclined surface 32 is configured by a curved surface, Strictly speaking, it does not hold. However, in the blanks base material 1 according to the present embodiment, the curvature radius of the curved surface constituting the inclined surface 32 is very large compared to the width W32 and the height T32 of the inclined surface 32. If the size and pitch of the concave portions 51 are set so as to satisfy the following formulas according to the shape, the contact angle θ5 with respect to the imprint resin of the concave / convex structure for contact angle adjustment 5 is set to the contact angle θ80 with respect to the imprint resin of the substrate 80 to be transferred. It is inferred that it can be made larger or smaller.
(When the recess 51 has a square hole shape in plan view. Ws: length of one side of the hole of the recess 51 in plan view, Wp: pitch of the recess 51 in plan view)
cos θ5 = ((Wp ² −Ws ² ) / Wp ² ) · cos θs + (Ws ² / Wp ² ) · cos θg
(When the recess 51 has a space shape. Ws: width in the short direction of the recess 51 in plan view, Wp: pitch of the recess 51 in plan view)
cos θ5 = ((Wp−Ws) / Wp) · cos θs + (Ws / Wp) · cos θg
(When the recess 51 has a circular hole shape in plan view. Ws: radius of the hole of the recess 51 in plan view, Wp: pitch of the recess 51 in plan view)
cos θ5 = ((Wp ² −πWr ² ) / Wp ² ) · cos θs + (πWr ² / Wp ² ) · cos θg

  The dimension on the inclined surface 32 of the concave portion 51 of the concavo-convex structure 5 for adjusting the contact angle may be larger than the dimension at the bottom portion of the concave portion 51. In this case, the dimension of the concave portion 51 gradually decreases from the inclined surface 32 toward the bottom portion. You may do it. For example, the cross-sectional shape of the recess 51 may be needle-shaped (see FIG. 11), or the size of the recess 51 may gradually decrease from the middle of the recess 51 toward the bottom (FIG. 12). Reference), the bottom of the recess 51 may have a curved shape (see FIG. 13).

  A recess 4 having a predetermined size is formed on the back surface 2 </ b> B of the base 2. By forming the dent 4, the imprint process using the imprint mold 10 (see FIG. 15) manufactured from the blanks substrate 1 according to the present embodiment, particularly when in contact with the imprint resin, When the imprint mold 10 is peeled off, the base portion 2, particularly the upper surface 31 of the convex structure portion 3 can be curved. As a result, when the upper surface 31 of the convex structure portion 3 and the imprint resin are brought into contact with each other, a gas is formed between the uneven pattern 11 (see FIG. 15) formed on the upper surface 31 of the convex structure portion 3 and the imprint resin. Can be prevented from being sandwiched, and the imprint mold 10 can be easily peeled from the transfer pattern formed by transferring the concavo-convex pattern 11 to the imprint resin.

  It is preferable that the planar view shape of the hollow part 4 is a substantially circular shape. Due to the substantially circular shape, the imprint mold 10 is formed at the time of imprint processing, particularly when the upper surface 31 of the convex structure 3 is brought into contact with the imprint resin or when the imprint mold 10 is peeled off from the imprint resin. The upper surface 31 of the convex structure part 3 can be curved substantially uniformly in the plane.

  As shown in FIG. 14, the size of the hollow portion 4 in plan view is such a size that the convex structure portion 3 is included in the projection region in which the hollow portion 4 is projected onto the surface 2 </ b> A side of the base portion 2. As long as it is not particularly limited. If the projection area has such a size that the convex structure portion 3 cannot be included, the entire upper surface of the convex structure portion 3 of the imprint mold 10 (see FIG. 15) may not be effectively curved.

  In the blanks substrate 1 according to this embodiment, at least the inclined surface 32 may be formed with a light shielding layer (not shown) made of a chromium-based compound or the like. Since the light shielding layer is formed on the inclined surface 32, it is possible to prevent the imprint resin protruding outside from the pattern area PA from being cured.

[Imprint mold]
FIG. 15 is a cut end view showing a schematic configuration of the imprint mold in the present embodiment.
As shown in FIG. 15, the imprint mold 10 according to the present embodiment has the concave / convex pattern 11 formed in the pattern area PA set on the upper surface 31 of the convex structure portion 3 of the blanks substrate 1 according to the present embodiment. Is.

  The shape, size, and the like of the uneven pattern 11 can be appropriately set according to the shape, size, and the like required for a product or the like manufactured using the imprint mold 10 in the present embodiment. For example, the shape of the concavo-convex pattern 11 includes a line and space shape, a pillar shape, a hole shape, a lattice shape, and the like. Moreover, the dimension of the uneven | corrugated pattern 11 can be set to about 10 nm-200 nm, for example. In addition, the dimension of the uneven | corrugated pattern 11 means the width | variety of the transversal direction of the recessed part or convex part, when the uneven | corrugated pattern 11 is a line and space shape or a grid | lattice form, and the uneven | corrugated pattern 11 is a pillar shape or a hole shape. In this case, it means the diameter or the length of one side of the concave or convex portion.

[Method for producing blanks substrate]
A method for producing the blanks substrate 1 according to the present embodiment will be described. 16 to 21 are partially enlarged cut end views showing respective steps of the method for manufacturing a mold base according to the present embodiment. In addition, the same code | symbol is attached | subjected to the structure similar to the said blanks base material 1, and the detailed description shall be abbreviate | omitted.

  First, a base 2 having a front surface 2A and a back surface 2B opposite to the front surface 2A, and a convex structure portion 3 located at a substantially central portion in plan view on the front surface 2A side of the base portion 2 and projecting from the front surface 2A are provided. A molding substrate 1 ′ 3 having an upper surface 31, an inclined surface 32, and a side surface 33 is prepared (see FIG. 16). The mold substrate 1 ′ has the same configuration as that of the blanks base material 1 (see FIGS. 1 to 3) according to the present embodiment except that the contact angle adjusting uneven structure 5 is not formed on the inclined surface 32. .

  In the present embodiment, the hard mask layer 6 is formed on the upper surface 31, the inclined surfaces 32 and the side surfaces 33 of the convex structure portion 3 of the mold substrate 1 ′, and the surface 2 </ b> A of the base portion 2. Examples of the material constituting the hard mask layer 6 include metals such as chromium, titanium, tantalum, silicon, and aluminum; chromium-based compounds such as chromium nitride, chromium oxide, and chromium oxynitride, tantalum oxide, tantalum oxynitride, and boron oxide. Tantalum compounds such as tantalum tantalum and tantalum oxynitride, titanium nitride, silicon nitride, silicon oxynitride and the like can be used alone or in combination of two or more selected arbitrarily.

  The hard mask layer 6 is patterned in a process described later (see FIG. 20), and is used as a mask when etching the mold substrate 1 '. Therefore, it is preferable to select the constituent material of the hard mask layer 6 in consideration of the etching selection ratio and the like according to the type of the mold substrate 1 ′. For example, when the mold substrate 1 ′ is a quartz glass substrate, a metal chromium film or the like can be suitably selected as the hard mask layer 6.

  The thickness of the hard mask layer 6 is appropriately set in consideration of the etching selection ratio according to the type of the mold substrate 1 ′, the aspect ratio of the concavo-convex structure for contact angle adjustment 5 in the blank substrate 1 to be manufactured, and the like. . For example, when the mold substrate 1 ′ is a quartz glass substrate and the hard mask layer 6 is a metal chromium film, the thickness of the hard mask layer 6 can be set to about 1 nm to 20 nm.

  The method of forming the hard mask layer 6 on the mold substrate 1 ′ is not particularly limited, and known film forming methods such as sputtering, PVD (Physical Vapor Deposition), and CVD (Chemical Vapor Deposition) are available. Can be mentioned.

  Next, a resist film 7 that covers at least the upper surface 31 and the inclined surface 32 of the convex structure portion 3 (hard mask layer 6) of the mold substrate 1 'is formed (see FIG. 17). The resist film 7 is formed, for example, by applying a known positive photosensitive resin material on the hard mask layer 6 by spin coating or the like, and removing the organic solvent contained in the photosensitive resin material by heating or the like. Can be done. Here, the positive-type photosensitive resin material is present in an unexposed portion that is not exposed by removing a material present in an exposed portion exposed through a photomask by a developing process of a resist film 7 described later. It is a photosensitive resin material in which the material remains.

  The film thickness of the resist film 7 is not particularly limited, and is appropriately set to such an extent that the resist pattern 71 does not disappear during the etching process of the hard mask layer 6 using a resist pattern 71 described later as a mask. obtain.

  A photomask having a light-shielding pattern corresponding to the contact angle adjusting concavo-convex structure 5 is prepared, and light L in a specific wavelength region, for example, ultraviolet rays, is passed through a photomask (not shown) aligned with the mold substrate 1 ′. The resist film 7 is irradiated with an electron beam or the like (see FIG. 18). The exposure through the photomask is, for example, contact exposure in which the photomask is brought into close contact with the resist film 7 and exposed from the back side of the photomask, and the photomask is arranged away from the resist film 7 from the back side of the photomask. Proximity exposure for exposure, an optical device such as a lens or mirror between the photomask and the resist film 7, and projection exposure in which light transmitted through the photomask is projected onto the resist film 7 through the optical device. Can be performed by: Further, a pattern latent image corresponding to the contact angle adjusting concavo-convex structure 5 may be directly drawn and exposed on the resist film 7 using an electron beam drawing apparatus or the like. By forming the resist pattern 71 (see FIG. 19) corresponding to the contact angle adjusting uneven structure 5 with high accuracy, the contact angle adjusting uneven structure 5 can be formed with high accuracy. In the present embodiment, the resist pattern 71 is formed on the inclined surface 32. The height T32 of the inclined surface 32 (the height position of the inner peripheral edge portion 32A and the outer peripheral edge portion 32B in the thickness direction of the base portion 2). If the difference is too large (too high), the electron beam drawing apparatus may recognize an error and cannot be drawn. Even if the image can be drawn, the dimensional accuracy of the resist pattern 71 may be reduced due to the influence of the electron beam blur. Similarly, in the case of contact exposure using an electron beam, if there are portions on the resist film 7 having different distances from the photomask, the dimensional accuracy of the resist pattern 71 may be reduced. In this regard, as in the present embodiment, when the height T32 of the inclined surface 32 is about 100 μm or less, the above-described problem hardly occurs and the resist pattern 71 can be formed with high accuracy.

  The exposed resist film 7 is developed to form a resist pattern 71 (see FIG. 19). For example, by using a known method such as a spray method, a dipping method, or a paddle method, a developing solution such as an organic solvent or an organic alkaline aqueous solution is brought into contact with the resist film 7 to dissolve and remove the resist film 7 present in the exposed portion. Rinse with a rinse solution such as water. Thus, a light shielding pattern of the photomask, that is, a resist pattern 71 corresponding to the contact angle adjusting concavo-convex structure 5 is formed.

  Using the resist pattern 71 as a mask, the hard mask layer 6 formed on the inclined surface 32 of the mold substrate 1 ′ is etched by, for example, a dry etching process using a chlorine-based (Cl2 + O2) etching gas. A mask pattern 61 is formed (see FIG. 20). Thereafter, the remaining resist pattern 71 is removed by wet etching or the like.

  Finally, by using the hard mask pattern 61 as a mask, the mold substrate 1 ′ is dry-etched to form the contact angle adjusting concavo-convex structure 5, and the hard mask pattern 61 is removed. Thus, the blanks base material 1 which concerns on this embodiment is manufactured (refer FIG. 22).

  By forming a desired hard mask pattern on the upper surface 31 of the convex structure portion 3 of the blanks substrate 1 manufactured as described above, and performing a dry etching process on the blanks substrate 1 using the hard mask pattern as a mask. The uneven pattern 11 is formed. Thereby, the imprint mold 10 can be manufactured. For the hard mask pattern, a resist film is formed on the hard mask layer formed on the upper surface 31 of the convex structure portion 3, and an exposure development process or a direct exposure development process through a photomask having a light shielding pattern corresponding to the concavo-convex pattern 11. It can be formed by etching using the resist pattern formed by the above as a mask and etching using the resist pattern formed by imprinting using a master mold having a concavo-convex pattern corresponding to the concavo-convex pattern 11 as a mask.

[Imprint method]
An imprint method using the imprint mold 10 having the above-described configuration will be described. 22 and 23 are process flowcharts showing each process of the imprint method in the present embodiment on a cut end face.

  First, an imprint mold 10 and a transfer substrate 80 having a transfer surface 80A and a facing surface 80B facing the transfer surface 80A are prepared (see FIG. 22A). As the transfer substrate 80, for example, a quartz glass substrate, a soda glass substrate, a calcium fluoride substrate, a magnesium fluoride substrate, an acrylic glass, or the like, or two or more substrates arbitrarily selected from these are laminated. Examples thereof include a transparent substrate such as a laminated substrate; a metal substrate such as a nickel substrate, a titanium substrate, and an aluminum substrate; and a semiconductor substrate such as a silicon substrate and a gallium nitride substrate.

  The contact angle of the transferred surface 80A with the imprint resin 81 (see FIG. 22B) may be larger than the contact angle of the inclined surface 32 of the convex structure portion 3 of the imprint mold 10 with the imprint resin 81. It can be small.

  Next, the imprint resin 81 is supplied to the transfer surface 80A side of the transfer substrate 80 (see FIG. 22B). As the imprint resin 81, a conventionally known ultraviolet curable resin or the like can be used. The supply amount of the imprint resin 81 depends on the remaining film thickness of the pattern structure 82 (see FIG. 23B) produced by the imprint method in the present embodiment, the volume of the uneven pattern 11 of the imprint mold 10, and the like. Can be appropriately calculated and determined. At this time, in order to prevent a defect (unfilled defect) from occurring in the pattern structure 82 due to an insufficient supply amount of the imprint resin 81, the supply amount of the imprint resin 81 is determined based on the remaining film thickness of the pattern structure 82 and The amount may be determined to be slightly larger than the amount calculated according to the volume of the uneven pattern 11 of the imprint mold 10.

  Subsequently, the concavo-convex pattern 11 (pattern area PA) on the upper surface 31 of the convex structure portion 3 of the imprint mold 10 is brought into contact with the imprint resin 81, and the concavo-convex pattern of the transferred surface 80 A of the transferred substrate 80 and the imprint mold 10. 11 (pattern area PA), the imprint resin 81 is developed (see FIG. 22C). At this time, the imprint resin 81 spreads so as to spread outward from the pattern area PA and reaches the inclined surface 32 of the imprint mold 10. Since the contact surface adjusting uneven structure 5 is formed on the inclined surface 32, the protrusion of the imprint resin 81 can be suppressed.

  In this state, the imprint resin 81 is irradiated with energy rays (UV, etc.) EL through the imprint mold 10 to cure the imprint resin 81 (see FIG. 23A).

  Finally, the imprint mold 10 is peeled from the cured imprint resin 81 (see FIG. 23B). Thereby, the pattern structure 82 formed by transferring the uneven pattern 11 of the imprint mold 10 onto the transfer surface 80A of the transfer substrate 80 can be produced.

  As described above, by performing the imprint process using the imprint mold 10 according to the present embodiment, it is possible to prevent the imprint resin 81 from protruding outside the convex structure portion 3 of the imprint mold 10. . Therefore, when a plurality of imprint processes are repeated on the transfer surface 80A of the transfer substrate 80 by the step-and-repeat method, adjacent imprint regions (imprinted regions) on the transfer surface 80A of the transfer substrate 80. ) Can be narrowed, and the number of imprint processes in one transfer substrate 80 can be increased. Further, if the imprint resin 81 protrudes and hardens so as to rise along the outer side (side surface 33) of the convex structure portion 3, the imprint mold 10 may be damaged by the raised and hardened portion, or particles may be generated. In the imprint process using the imprint mold 10 according to the present embodiment, the imprint resin 81 is prevented from protruding to the outside (side surface 33) of the convex structure 3. Therefore, damage to the imprint mold 10 and generation of particles can be prevented.

  The embodiment described above is described for facilitating understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

  In the said embodiment, the convex structure part 3 which protrudes from 2 A of surfaces of the base 2 was provided, and it demonstrated and demonstrated the aspect in which the uneven structure 5 for contact angle adjustment was formed in the inclined surface 32 of the convex structure part 3 as an example. However, it is not limited to this aspect. For example, as shown in FIG. 24, the surface 2A of the base portion 2 does not have the convex structure portion 3 and includes the inclined surface 22 surrounding the pattern area PA set on the surface 2A, and the contact angle with the inclined surface 22 The adjustment uneven structure 5 may be formed.

  In the said embodiment, the light shielding layer which coat | covers the inclined surface 32 (uneven structure 5 for contact angle adjustment) at least may be provided. In this case, the light-shielding layer usually has a desired light-shielding performance (for example, an optical density value (OD value) of 3) with respect to light irradiated on the imprint resin 81 (for example, light having a wavelength of 200 nm to 450 nm). The material constituting the light-shielding layer is, for example, chromium-based materials such as chromium, chromium oxide, chromium nitride, and chromium oxynitride; molybdenum-based materials such as molybdenum and molybdenum silicide; gold Etc. can be used. Since the light shielding layer covering the inclined surface 32 is provided, the imprint that protrudes outward from the upper surface 31 (pattern area PA) of the convex structure portion 3 and contacts the inclined surface 32 (concave structure 5 for contact angle adjustment). The resin 81 shields the energy rays (UV, etc.) EL traveling along the thickness direction of the base portion 2 of the imprint mold 10, and the energy rays (UV, etc.) EL of the convex structure portion 3 of the imprint mold 10 are shielded. It is possible to prevent the imprint resin 81 from protruding from the upper surface 31 (pattern region PA) and remaining on the inclined surface 32 (contact angle adjusting uneven structure 5) from being irradiated.

  In the above embodiment, the resist film 7 made of a positive photosensitive resin material is formed on the upper surface 31 and the inclined surface 32 of the convex structure portion 3 (hard mask layer 6) of the mold substrate 1 ′. However, the resist film 7 may be made of a negative photosensitive resin material.

  In the said embodiment, although the hollow part 1 and the imprint mold 10 demonstrated and demonstrated the example in which the hollow part 4 was formed in the back surface 2B side of the base 2, it is not limited to this aspect. . For example, the recessed portion 4 may not be formed on the back surface 2B side of the base portion 2. When imprinting on the transfer substrate 80 using the imprint mold 10 in which the recess 4 is not formed, the recess is formed on the surface 80B of the transfer substrate 80 facing the transfer surface 80A. Is desirable.

  In the said embodiment, although demonstrated taking the blanks base material 1 by which the uneven | corrugated structure 5 for contact angle adjustment was provided in the inclined surface 32 as an example, it is not limited to this aspect. For example, although the blanks base material 1 is not formed with the concavo-convex structure 5 for contact angle adjustment, it may have an inclined surface 32 that can form the concavo-convex structure 5 for contact angle adjustment. In this case, the contact angle adjusting concavo-convex structure 5 may be formed simultaneously with the concavo-convex pattern 11, or may be formed separately from the concavo-convex pattern 11.

  In the blanks substrate 1 and the imprint mold 10 of the above embodiment, the contact angle with respect to the imprint resin of the inclined surface 32 of the convex structure portion 3 is larger than the contact angle with respect to the imprint resin of the upper surface 31 of the convex structure portion 3. Also good. The imprint resin between the upper surface 31 of the convex structure portion 3 and the transferred surface 80A of the transferred substrate 80 protrudes along the inclined surface 32 of the convex structure portion 3, but the contact angle of the inclined surface 32 is the upper surface. When the contact angle is larger than 31, the protrusion of the imprint resin can be suppressed.

  INDUSTRIAL APPLICABILITY The present invention is useful in technical fields such as an imprint mold used in a semiconductor device manufacturing process and the like, and a mold base material for manufacturing the imprint mold.

DESCRIPTION OF SYMBOLS 1 ... Blanks base material 2 ... Base part 3 ... Convex structure part 31 ... Upper surface 32 ... Inclined surface 33 ... Side surface 4 ... Depression part 10 ... Imprint mold 11 ... Uneven pattern

Claims (18)

A base having a first surface, a second surface facing the first surface, and a third surface surrounding the outside of the pattern region set on the first surface and having a functional region set;
A concavo-convex structure for contact angle adjustment formed on the third surface,
The third surface has an inner peripheral edge that is continuous with the outer edge of the first surface, and an outer peripheral edge that is located closer to the second surface than the inner peripheral edge.
The contact angle adjusting concavo-convex structure portion is a blank base material having a concavo-convex direction substantially orthogonal to the first surface. The blanks substrate according to claim 1, wherein the third surface includes a first inclined surface having a first inclination angle and a second inclined surface having a second inclination angle different from the first inclination angle. The blank base material according to claim 2, wherein the first inclination angle is larger than the second inclination angle. The blank base material according to claim 2, wherein the first inclination angle is smaller than the second inclination angle. The blank base material according to claim 1, wherein the third surface includes a concave curved surface that is concave toward the second surface. The blank substrate according to claim 1, wherein the third surface includes a convex curved surface that is convex toward the first surface. The blanks substrate according to claim 1, wherein the third surface is an inclined surface that is inclined from the inner peripheral edge toward the outer peripheral edge. The blanks substrate according to any one of claims 1 to 7, wherein a concave width on the third surface side of the concave portion of the concave-convex structure for adjusting the contact angle is larger than a concave width at a bottom portion of the concave portion. The blank base material according to claim 8, wherein the concave width of the concave portion of the contact angle adjusting concave-convex structure gradually decreases from the third surface side toward the bottom portion. The blank substrate according to any one of claims 1 to 7, wherein the concave width of the concave portion of the contact angle adjusting concave-convex structure is substantially the same in the depth direction of the concave portion. The blanks substrate according to claim 1, wherein a difference in height between the inner peripheral edge and the outer peripheral edge in the thickness direction of the base is 100 μm or less. The blanks substrate according to any one of claims 1 to 11, further comprising a light-shielding film that covers at least the third surface.   The imprint mold which has an uneven | corrugated pattern formed in the said pattern area | region of the blanks base material in any one of Claims 1-12. A method for producing an imprint mold according to claim 13, comprising:
Forming a mask pattern corresponding to the concavo-convex pattern in the pattern region of the blanks substrate;
The imprint mold manufacturing method which has the process of forming the said uneven | corrugated pattern by etching the said blanks base material in which the said mask pattern was formed. An imprint method using the imprint mold according to claim 13,
Preparing a transfer substrate having a transfer surface having wettability different from wettability to the imprint resin of the third surface of the imprint mold;
Supplying the imprint resin to the transfer surface;
Transferring the concavo-convex pattern to the imprint resin by bringing the concavo-convex pattern into contact with the imprint resin on the transfer surface;
A step of separating the imprint mold from the imprint resin to which the uneven pattern has been transferred. The imprint method according to claim 15, wherein a contact angle of the third surface with the imprint resin is larger than a contact angle of the transfer surface with the imprint resin. The imprint method according to claim 15, wherein a contact angle of the third surface with respect to the imprint resin is smaller than a contact angle of the transferred surface with respect to the imprint resin. The imprint method according to claim 15, wherein a contact angle of the third surface with respect to the imprint resin is larger than a contact angle of the pattern region of the first surface with respect to the imprint resin.

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