Mould, embossing device and method of making an article

Abstract

The present invention provides a mold, an imprinting device, and a method for manufacturing an article. In order to effectively demold even when the force applied to the mold is reduced, a mold used in an imprinting device is provided, which molds an imprinting material by imprinting the imprinting material on a substrate with an imprinting surface of the mold, and demolds the mold by applying a force in a release direction to a peeling area near the periphery of the mold, wherein the flexibility of the peeling area of ​​the mold is higher than the flexibility of other parts near the periphery of the mold.

Description

Technical Field

[0001] The invention relates to a mould, an embossing device and a method of manufacturing an article. Background Art

[0002] Imprint technology is known as one of the photolithography technologies for manufacturing articles such as semiconductor devices, etc. When the imprint technology is used, a nanometer-scale pattern (structure) can be formed by transferring a pattern of a mold to an imprint material (resin) on a substrate.

[0003] In an imprinting device using a photocuring method of imprinting technology, first, a photocurable imprinting material is supplied to a substrate. Next, the imprinting material is molded by imprinting a mold on the imprinting material. Then, the molded imprinting material is irradiated with light to cure the imprinting material. By demolding the mold, a pattern can be formed on the substrate.

[0004] U.S. Patent No. 7,179,079 discloses a technology in which a groove is formed on a non-imprinting surface so that the imprinting surface of the mold follows the shape of the substrate during imprinting. In addition, Japanese Patent Publication No. 2018-190844 discloses a technology in which the thickness of the core part (pattern periphery) is changed according to the position to remove bubbles remaining in the groove of the mold pattern part during imprinting and shorten the filling time. For this reason, in Japanese Patent Publication No. 2018-190844, the periphery of the mold is made thicker than other parts of the mold. As described above, these technologies are used to improve the problems in the imprinting step by forming a groove on the back side of the pattern part or the position of the pattern periphery and partially changing the thickness of the mold.

[0005] On the other hand, in recent years, the imprint technology has been expanding applications other than for forming a pattern for each shot, and is being applied to a planarization technology called inkjet-based adaptive planarization (IAP).

[0006] Unlike the mold used in the prior art imprint, the mold used in IAP is composed of a flat plate with a large size of about Φ300 mm and does not even have a core portion. By imprinting such a mold on the imprint material on the substrate all at once, a flat layer can be formed on the substrate.

[0007] Compared with the imprinting of the prior art in which a pattern is formed for each lens, in IAP, the area used for one imprinting is larger, resulting in a new problem that the force required for demolding is also larger. Therefore, it is necessary to smoothly separate the mold from the imprinting material on the substrate, which should be performed in the demolding step of the prior art.

[0008] Therefore, an object of the present invention is to provide a mold capable of smoothly releasing a mold from an imprinting material. Summary of the invention

[0009] To achieve this objective, according to one aspect of the present invention, there is provided a mold for use in an imprinting device, which molds an imprinting material by imprinting the imprinting material on a substrate with an imprinting surface of the mold, and demolds the mold by applying a force in a release direction to a peeling area near the periphery of the mold, wherein the flexibility of the peeling area of ​​the mold is higher than the flexibility of other parts near the periphery of the mold.

[0010] Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a diagram illustrating an example of an imprint apparatus.

[0012] Figure 2A is a diagram of the mold 11 viewed from the non-imprinting surface. Figure 2B yes Figure 2A An enlarged view of the groove 111 of the mold 11. Figure 2C yes Figure 2A FIG. 1 is an enlarged view of another type of groove 111 of the mold 11 . Figure 2D yes Figure 2A FIG. 1 is an enlarged view of another different type of groove 111 of the mold 11 .

[0013] Figure 3A This is a diagram showing a mold in which one type of groove is provided over the entire outer peripheral end. Figure 3B This is a diagram showing a mold in which another type of groove is provided over the entire outer peripheral end.

[0014] Figure 4 A in FIG. 2 is a cross-sectional view of the mold 11 taken along the dotted line in FIG. 2 . Figure 4 B in FIG. 1 is a diagram showing that the ejector pin 23 passes through the notch portion 230 and is lifted up.

[0015] Figure 5 It is a diagram showing an example of a mold releasing method using gas.

[0016] Figure 6 This is a diagram of the mold viewed from the non-imprinting surface side.

[0017] Fig. 7A is a diagram showing a mold in which a mold groove is filled with a filler. Figure 7B 2 is a diagram showing a mold in which a filler filled in a mold groove is bent when the ejector pin 23 is lifted.

[0018] Fig. 8A 115 and 116 in Embodiment 2. Figure 8B1 is a diagram showing the heights of the suction portions 115 and 116 in Example 2 when the peeling region 112 is peeled off.

[0019] Fig. 9A is a diagram showing still another example of the mold suction area. Fig. 9B 11 and 114 are diagrams showing the positional relationship between the non-imprinting surface of the mold and the suction portions 115 and 116 in an overlapping manner. DETAILED DESCRIPTION

[0020] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings and examples.

[0021] <Example 1>

[0022] Figure 1 1 is a diagram of an imprinting device. The imprinting device 10 is a device for manufacturing an article such as a semiconductor device by contacting (pressing) an imprinting material 21 on a substrate with an imprinting surface of a mold 11 to form a pattern on a processing target substrate. In addition, the imprinting technology is not limited to the imprinting of individual lenses of the related art, but can be applied to a flattening technology called IAP. Here, since flatness can also be considered as one of the patterns, the pattern used in the following description includes flatness, and pattern formation (molding) includes imprinting (contact) for flattening.

[0023] The imprinting device 10 includes a head 12 supported by a structure 18, and holds a mold 11 on its lower side, the mold 11 having a flat surface for flattening the surface of a pattern of an imprint material or a circuit pattern, etc. The head 12 can move the mold 11 toward and away from the substrate 13 (vertical direction in the figure) with a driving source (not shown) and a control unit 50 to bring the mold 11 and the imprint material 21 into contact with each other (imprinting) and to separate the mold from the imprint material (demolding). The substrate stage 14 holding the substrate 13 can be moved to an arbitrary position on the stage plate 19 by a driving mechanism 15. The control unit 50 includes a recording unit 51 for recording the measured values ​​of the positions of the head 12 and the substrate stage 14. In addition, the control unit 50 has a built-in CPU as a computer, and serves as a control device for performing various operations of the entire device based on a computer program stored in a memory (not shown).

[0024] When the imprint material 21 is supplied to the substrate 13, the substrate stage 14 is moved so that the imprint area is located directly below the ejection unit (dispenser) 20, and the imprint material 21 is supplied (ejected) from the ejection unit 20. As a method of supplying the imprint material 21 onto the substrate 13, Figure 1In the embodiment, as described above, one head 12 is provided for one ejection unit 20, however, a plurality of heads 12 or a plurality of substrate stages 14 may be provided for one ejection unit 20. Alternatively, the imprint material 21 may be applied to the substrate 13 in advance using an external device or a dedicated unit, and then the substrate 13 to which the imprint material has been applied may be transferred to the substrate stage 14.

[0025] When the mold 11 is imprinted (pressed) on the imprint material 21, the substrate stage 14 is moved so that the imprint area where the imprint material 21 is supplied is located directly below the mold 11. At this time, the position of the substrate stage 14 in the plane direction is measured by the stage length measurement unit 22, and the substrate stage 14 is aligned by the control mechanism and the alignment mechanism (not shown). Then, the head 12 holding the mold 11 is driven toward the substrate 13 so that the mold 11 contacts (presses) the imprint material 21.

[0026] Thereafter, in order to cure the imprint material 21 molded on the substrate 13, the exposure light emitted from the ultraviolet light source 16 is guided by the illumination optical system 17, and the imprint material 21 in contact with the mold 11 is irradiated with the exposure light having passed through the transparent mold 11. The imprint material 21 is a photocurable composition having a property of being cured by receiving ultraviolet rays, and the composition is appropriately selected according to various conditions such as a semiconductor device manufacturing process, etc. If a thermosetting method is adopted, a heat source such as a heater built in the mold holding unit is used, and the composition of the imprint material 21 to be cured according to the temperature is appropriately selected.

[0027] When the mold 11 is demolded from the imprint material 21, the head 12 holding the mold 11 is driven away from the substrate 13 (upward in the figure). At this time, especially in IAP, since the area imprinted at one time is large, the force required for demolding is also large, so it may sometimes be difficult to demold only under the drive of the head 12. Alternatively, the mold 11 may sometimes be detached from the head 12, or the substrate 13 may sometimes be detached from the substrate stage 14. Therefore, in this example, in addition to the upward drive of the head 12, a biasing portion such as an ejector pin (protrusion) 23 is provided in the substrate stage 14, which protrudes upward from the inside of a V-shaped notch portion 230 (cutout) pre-provided in the substrate 13. Then, the ejector pin 23 is demolded by applying a force in the release direction to the imprint surface of the mold 11 from the inside of the notch portion while avoiding contact with the substrate. That is, it is characterized in that the ejector pin 23 is provided as a protrusion inside the recessed portion of the substrate, and the ejector pin 23 applies a force to the peeling area near the outer periphery of the mold from the imprinting surface side in the releasing direction. Although the ejector pin 23 as the biasing portion has a pin shape in the present embodiment, it may have a shape other than the pin shape such as a protrusion.

[0028] In addition, multiple ejector pins may be provided at multiple locations on the substrate stage 14, and multiple recesses may be provided on the substrate, or the peripheral portion of the mold may be suspended from the substrate so that multiple peripheral portions of the mold can be lifted by the multiple ejector pins.

[0029] Figure 2A 1 is a diagram of the mold 11 viewed from the non-embossing surface, and a groove 111 is provided in a peeling region 112 of the non-embossing surface in the peripheral end of the mold 11. Preferably, the groove 111 is provided in the peeling region 112 within a range of 10 mm from the peripheral end of the mold 11. The peeling region 112 is provided on the molding surface on the side opposite to the position where the ejector pin 23 contacts the mold, and the peeling region 112 and the groove 111 are provided to be substantially axisymmetric with respect to a straight line connecting the position where the ejector pin contacts the mold and the center of the mold. Figure 2B and Figure 2C yes Figure 2A An enlarged view of the groove 111 of the mold 11. The groove is cut in the mold 11 along a direction substantially orthogonal to the direction in which the imprint material 21 is peeled off during demolding (the direction of the straight line connecting the position where the ejector pin contacts the mold and the center of the mold).

[0030] In other words, while the mold is gradually peeled off from the imprint material, the grooves are cut along the peeling curves of the mold formed at multiple times. Figure 2B As shown, the groove of the stripping area 112 of the mold 11 has an arc shape centered on a predetermined point on the straight line connecting the position where the ejector pin contacts the mold and the center of the mold. Alternatively, as described above, the groove can be cut in a direction substantially orthogonal to the direction of the straight line between the position where the ejector pin contacts the mold and the center of the mold, such as Figure 2C However, Figure 2D As shown, the groove can be configured to be axisymmetric and have a small acute angle θ relative to the straight line connecting the position where the ejector pin contacts the mold and the center of the mold. Generally, the groove should be configured to intersect the straight line between the position where the ejector pin contacts the mold and the center of the mold and be axisymmetric relative to the straight line.

[0031] By forming such a groove, the flexibility of the peeling area near the periphery of the mold can be made higher than the flexibility of other parts near the periphery of the mold, so if the demolding force is applied to the mold by a biasing portion such as an ejector pin, damage to the mold can be reduced and the mold can be demolded smoothly. Note that the groove shape may include a grid shape in which grooves in different directions intersect each other, a periodic or random shape, an uneven shape, a fine or rough shape, etc.

[0032] Furthermore, the groove 111 may be provided not only in the peeling region 112 of a portion of the periphery of the mold, but also in the entire periphery of the mold, such as Figure 3A As shown, the groove 111 may have a circular shape centered on the center of the mold 11, as shown in FIG. Figure 3B shown.

[0033] If the groove 111 is provided in the entire area of ​​the outer peripheral end, the mold 11 can be set in multiple directions or in any direction. Therefore, the mold position contacting the ejector pin 23 can be appropriately changed, and the number of times of contact and bending can be reduced, so that damage such as scratches and fatigue fracture of the mold 11 can be reduced, and the life of the mold can be extended.

[0034] Figure 4 A in FIG. 2 is a cross-sectional view of the mold 11 along the dotted line (a straight line connecting the position where the ejector pin contacts the mold and the center of the mold) in FIG. Figure 4 B in FIG. 1 is a diagram in which the ejector pin 23 is lifted through the notch portion 230 (a region cut out in a V shape when the substrate is viewed from the top side) of the substrate 13 without contacting the notch portion 230 and force is directly applied to the peeling area 112 of the imprinting surface of the mold 11 .

[0035] The groove 111 is provided at a position on the back side of the mold corresponding to the position where the ejector pin 23 applies a force to the mold 11, and the applied force is propagated to the groove 111 to bend the mold 11 and promote demolding between the mold 11 and the imprint material 21. Therefore, by providing the groove 111 of the mold 11 around a position on the side of the mold opposite to the position where the ejector pin 23 provided on the substrate stage 14 of the imprint apparatus 10 contacts the mold, a good effect can be obtained.

[0036] The imprinting apparatus detects the position of the peeling area 112 or the reference portion of the mold using a sensor or the like so that the position of the peeling area 112 is on the side opposite to the position of the ejector pins 23, and transfers and attaches the mold to the head 12. If grooves are provided at multiple positions or over the entire periphery of the mold, the angular position of the mold and the number of times the demolding operation is performed are stored in a memory, and after a predetermined number of times, when the mold is attached to the head 12, the angular position may be moved.

[0037] As a method of causing the ejector pin 23 to apply force to the mold 11 without contacting the substrate 13, the mold 11 may be made to have a larger diameter than the substrate 13 so that the substrate is moved overhand as a whole, or a region where the mold 11 and the substrate 13 do not overlap may be formed when imprinting is performed by offsetting the centers of the mold 11 and the substrate 13 from each other. In addition, since the ejector pin 23 may generate dust by pressing the mold 11, it is desirable to provide a suction mechanism at the tip of the ejector pin 23 or around the ejector pin.

[0038] In addition, as a method of reducing damage to the mold 11 and dust generation, as Figure 5 As shown, a flow path 231 for exhausting gas may be formed in the ejector pin 23. Gas is exhausted from the tip of the ejector pin 23 to the mold 11 to increase pressure on the imprinting surface, thereby facilitating demolding.

[0039] In this case, for example, the ejector pin 23 may be pressed against the mold while blowing air. Alternatively, only one may be operated first, and the other may be operated later. In addition, the flow path 231 may be configured to switch operation so that the flow path blows gas when promoting demolding, and the flow path performs a suction operation when vacuuming. By forming the flow path 231 as a blower in this way, damage to the mold 11 and dust generation can be reduced. Note that demolding / peeling can be performed only by blowing gas through the flow path 231 while the ejector pin 23 is not directly in contact with the mold.

[0040] Figure 6 is a diagram of the mold 11 viewed from the non-imprinting surface side, and the suction area 113 to be sucked and held by the head 12 is shown by diagonal grid lines. Figure 6 8 , for the sake of convenience, the surface of the suction area 113 (i.e., the surface other than the peeling area 112) is shown in a grid pattern, but in fact, the surface is flat so that the head 12 can effectively suck the mold. At the time of demolding, a force is applied to the imprinting surface of the mold 11 by the ejector pins 23, and while the mold 11 is sucked by the suction portion 115 of the head 12, the peeling area 112 of the mold 11 is peeled off from the substrate 13, as shown in FIG. 8 . Note that since the peeling area 112 is pushed upward by the ejector pins, the suction portion 115 is configured to suck the suction area 113 other than the peeling area 112. An elastic body may be provided at the top end of the suction portion 115, and if the bending amount of the elastic body is large enough, the suction portion 115 may suck the peeling area 112 and the suction area 113 together.

[0041] Fig. 7A and Figure 7B1 is a diagram showing an example of filling the groove 111 of the mold 11 with a filler 114 made of a material different from that of the mold 11. The force applied by the ejector pin 23 is propagated to the groove 111 of the mold 11 to bend the mold 11 and promote demolding between the mold 11 and the imprint material 21, while the provided groove may damage the mold 11 depending on the material of the mold. Therefore, in order to make the mold 11 easier to bend and less likely to be damaged, the groove 111 of the mold 11 can be filled with a filler 114 made of a material having a smaller Young's modulus than the material of the mold 11. Note that in this example, by providing a groove in the peeling area of ​​the non-imprinting surface, the flexibility of the peeling area of ​​the non-imprinting surface is made higher than the flexibility of other parts, but the flexibility of the peeling area of ​​the mold can be made higher than the flexibility of other parts near the periphery of the mold by making the thickness of the peeling area of ​​the mold thinner than the thickness of other parts. Alternatively, by forming a groove on the imprinting surface side of the peeling area, the flexibility of the peeling area can be made higher than the flexibility of other parts near the periphery of the mold (parts near the periphery of the mold other than the peeling area of ​​the mold). In this case, the groove on the imprint surface side may be filled with the filler 114 made of a material having a smaller Young's modulus than that of the material of the mold 11 .

[0042] <Example 2>

[0043] FIG8 is a diagram showing the suction portions 115 and 116 in Embodiment 2. Fig. 8A As shown, in order to suck the mold from the non-imprinting surface side, a suction portion 115 for sucking the suction area 113 is arranged to face the suction area 113 other than the peeling area 112. That is, the suction portion 115 constitutes a first suction portion for sucking the area other than the peeling area.

[0044] In addition, a suction portion 116 (second suction portion) serving as a biasing portion for sucking the peeling region 112 is provided to face the peeling region 112 of the mold. In addition, the suction portion 115 and the suction portion 116 are configured to be driven independently. Note that the suction portion 115 and the suction portion 116 suck the suction region 113 and the peeling region 112 of the mold 1, respectively.

[0045] When the mold 11 is demolded from the imprint material 21 on the substrate 13, the suction portion 116 facing the peeling area 112 performs suction with a suction force per unit area greater than the suction force per unit area of ​​the suction portion 115. Thus, the mold 11 is demolded from the imprint material 21 on the substrate 13. Then, the entire mold 11 moves in the direction of release from the imprint material 21 on the substrate 13, while the suction portion 116 is sucked more strongly than the suction portion 115. Therefore, as shown in FIG. Figure 8BAs shown, the suction portion 116 has a large upward movement amount, so that the peeling region 112 can be moved above the suction position of the suction portion 115 while the peeling region 112 is being sucked.

[0046] Note that, for example, when the mold 11 is demolded from the imprint material 21 on the substrate 13 by using the suction portion 116, the ejector pins 23 may simultaneously push up from below, or the blower may increase the air pressure to promote pushing up (biasing) from below and demolding together at the same time. That is, it is sufficient as long as demolding is promoted by using at least one of the suction portion 116, the ejector pins 23, and the blower.

[0047] Here, each of the suction portion 116, the blower, and the ejector pin 23 serves as a biasing portion.

[0048] FIG. 9 is a diagram showing a structural example of a non-imprinting surface of a mold corresponding to the configuration of the suction portions 115 and 116 of FIG. 8 .

[0049] exist Fig. 9A In FIG. 1 , a peeling region 112 facing the suction portion 116 is shown in the non-imprinting surface of the mold, and the surface other than the peeling region 112 is a flat surface. As shown in FIG. 2 , the peeling region 112 is provided with a groove 111. In FIG. 9 , the groove 111 is provided only on the portion facing the suction portion 116. In addition, Fig. 9B 11 and 114 are diagrams showing the positional relationship between the non-imprinting surface of the mold and the suction portions 115 and 116 in an overlapping manner.

[0050] like Fig. 9B As shown, the grooves 111 are configured so that both ends of each groove are not exposed from the opposite surface of the suction portion 116. That is, both ends of the groove are covered by the suction portion 116. This is to prevent the suction force of the suction portion 116 from leaking from the ends of the grooves 111. Since both ends of the grooves are covered by the suction portion 116, as described above, the mold 11 can be effectively demolded (peeled off) from the substrate 13, while the peeling area 112 has greater flexibility than other parts near the periphery of the mold.

[0051] Next, a method for manufacturing an article (semiconductor IC element, liquid crystal display element, MEMS, etc.) using the above-mentioned mold will be described. The article is manufactured by performing post-processing (processing of manufacturing an article from the imprinted substrate) after the step of imprinting a substrate to which an imprinting material is applied by using the above-mentioned mold and the step of demolding the mold from the imprinting material. The post-processing includes etching, resist stripping, cutting, bonding, packaging, etc. According to the article manufacturing method using the present invention, since demolding can be performed smoothly, the yield can be improved, and higher quality articles can be manufactured.

[0052] Note that a computer program that implements the functions of the above-mentioned examples can be supplied to the imprinting device through a network or various storage media, and part or all of the control in this example has been described in the above-mentioned examples. In addition, the computer (or CPU, MPU, etc.) in the imprinting device can read and execute the program. In this case, the program and the storage medium storing the program constitute the present invention.

[0053] While the present invention has been described with respect to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

[0054] This application claims the benefit of Japanese Patent Application No. 2019-149837, filed on August 19, 2019, which is hereby incorporated by reference herein in its entirety.

Claims

1. A mold used in an imprinting device, which molds an imprint material by bringing an imprinting surface of the mold into contact with the imprint material on a substrate, and demolds the mold by applying a force in a release direction to a peeling area near the periphery of the mold, in, The grooves are formed in the peeling region so that the flexibility of the peeling region of the mold is higher than that of other portions near the outer periphery of the mold.

2. The mold according to claim 1, wherein: The groove is formed in a direction intersecting with a direction in which the mold is peeled off from the imprint material when a force in a releasing direction is applied to the peeling region.

3. The mold according to claim 1, wherein: After the groove is formed, the groove is filled with a predetermined filler.

4. The mold according to claim 3, wherein: The Young's modulus of the material of the filler is lower than that of the material of the mold.

5. The mold according to claim 1, wherein: The depth of the groove is equal to or less than half the thickness of the mold.

6. The mold according to claim 1, wherein: The peeling area was arranged within a range of 10 mm from the outer peripheral end of the mold.

7. The mold according to claim 1, wherein: The peeling area is provided on the entire outer peripheral end of the mold.

8. The mold according to claim 1, wherein: In the surface of the mold on the side opposite to the imprinting surface, the surface other than the peeling region is flat.

9. An imprinting device comprising: a mold holding unit that holds a mold in which a peeling region is provided near the periphery of the mold and a groove is provided in the peeling region so that flexibility of the peeling region is higher than flexibility of other portions near the periphery of the mold, wherein the mold is used to mold an imprint material on a substrate by contacting an imprint surface of the mold with the imprint material, and the mold is demolded by applying a force in a releasing direction to the peeling region; and The biasing portion is used to apply a force in a releasing direction from the stamping surface side of the mold to the peeling area of ​​the mold when demolding is performed.

10. The imprinting apparatus according to claim 9, wherein: The biasing portion includes a protrusion disposed inside a recessed portion provided in the base plate.

11. The imprinting apparatus according to claim 9, wherein: The biasing portion has a blower that blows gas to apply a force in a releasing direction from the stamping surface side of the mold to the peeling region of the mold when the mold is released.

12. The imprinting apparatus according to claim 10, wherein: The protrusion has a blower for blowing gas from the imprinting surface side of the mold in the releasing direction.

13. The imprinting apparatus according to claim 9, further comprising: A first suction portion is used to suction a portion other than the peeling area in a surface of the mold on the side opposite to the imprinting surface.

14. The imprinting apparatus according to claim 13, wherein: The biasing portion includes a second suction portion for sucking the peeling area in a surface of the mold on a side opposite to the imprinting surface, and the second suction portion applies a stronger suction force than the first suction portion when demolding is performed.

15. A method for manufacturing an article by using an embossing apparatus, the embossing apparatus comprising: A mold holding unit that holds a mold in which a peeling region is provided near the periphery of the mold and a groove is provided in the peeling region so that the flexibility of the peeling region is higher than the flexibility of other parts near the periphery of the mold, wherein the mold is used to mold an imprint material by contacting an imprint surface of the mold with the imprint material on a substrate, and wherein the mold is demolded by applying a force in a release direction to the peeling region; and a biasing portion for applying a force in a release direction to the peeling region of the mold from the imprint surface side of the mold when demolding, the method comprising: imprinting the imprint material on the substrate through the mold; and The mold is released from the imprinting material.

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