Imprint method, mold, imprint device, and article manufacturing method

Abstract

To provide a technique advantageous for protecting a superposition pattern formed on a substrate and reducing an area where the superposition pattern is formed.SOLUTION: Provided is an imprint method for forming a pattern of an imprint material in both a first area on a substrate and a second area including an overlapping area overlapping an end of the first area, the method including: a first step of forming, in the first area, a first pattern of the imprint material including a main pattern and a first portion to be formed on a superimposition pattern formed in the overlapping area; and a second step of forming, in the second area, a second pattern of the imprint material including the main pattern and a second portion covering the first portion of the first pattern, wherein in the second step, the second pattern is formed so that the total film thickness of the pattern of the imprint material formed in the overlapping area becomes larger than the total film thickness of the main pattern of the second pattern.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to an imprinting method, a mold, an imprinting apparatus, and a method for manufacturing an article.

Background Art

[0002] In the manufacturing process of semiconductor elements, MEMS, etc., an imprinting material (a liquid fluid containing an uncured resin, etc.) is placed on a substrate, and a mold with concavo-convex processing is pressed against (contacted with) the imprinting material to form a predetermined pattern. An imprinting apparatus is used. The imprinting apparatus optically detects the alignment patterns provided on each of the mold and the substrate, thereby realizing high-precision alignment between the mold and the substrate, and forming a pattern having a fine structure on the order of several nanometers on the substrate.

[0003] Regarding an imprinting apparatus, a technique has been proposed to prevent the formation of a region without an imprinting material, that is, a gap, between a plurality of imprinting regions (shot regions) on a substrate where an imprinting process is performed (see Patent Document 1). Patent Document 1 discloses a method of performing an imprinting process on each imprinting region so as to overlap the outer peripheral portion (end portion) of adjacent imprinting regions on the substrate.

[0004] On the other hand, in the formation of a circuit pattern of a semiconductor element, the alignment (registration) accuracy between a pattern already formed on a substrate and a pattern to be formed hereafter is important. Therefore, in an imprinting apparatus, generally, a die-by-die method is adopted as a method of aligning a substrate and a mold. The die-by-die method is a method of detecting the alignment pattern provided on the substrate and the alignment pattern provided on the mold for each imprinting region on the substrate, and correcting the deviation of the positional relationship (relative position) between the substrate and the mold. Therefore, it is necessary to form an alignment pattern for each of a plurality of imprinting regions on the substrate and to form a large number of alignment patterns on the substrate.

Prior Art Documents

Patent Document

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, the overlay pattern on the substrate used when performing the imprint process on the first layer is etched away and deformed, so it cannot be used for the imprint process of the second layer and subsequent layers. Therefore, in order to perform the imprint process of the second layer and subsequent layers, an overlay pattern that can be used in the second layer must be provided in a region different from the overlay pattern used in the first layer, resulting in an increase in the area for forming the overlay pattern on the substrate.

[0007] In view of such problems of the prior art, the present invention is made, and an exemplary object is to provide a technique advantageous for protecting the overlay pattern formed on the substrate and reducing the area for forming the overlay pattern.

Means for Solving the Problems

[0008] To achieve the above object, as one aspect of the present invention, an imprint method includes forming a pattern of an imprint material in each of a first region on a substrate and a second region including an overlapping region overlapping with an end of the first region. The imprint method includes: a first step of forming a first pattern of the imprint material in the first region, the first pattern including a first portion formed on top of an overlapping pattern formed in the overlapping region and a main pattern; a second step of forming a second pattern of the imprint material in the second region, the second pattern including a second portion covering the first portion of the first pattern and a main pattern; and in the second step, forming the second pattern such that a total film thickness of the pattern of the imprint material formed in the overlapping region is greater than a total film thickness of the main pattern of the second pattern.

[0009] A further object or other aspect of the present invention will be clarified by embodiments described below with reference to the accompanying drawings.

Advantages of the Invention

[0010] According to the present invention, for example, it is possible to provide a technique advantageous for protecting an overlapping pattern formed on a substrate and reducing a region for forming the overlapping pattern.

Brief Description of the Drawings

[0011]

Figure 1

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Figure 8

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Figure 12

Embodiments for Carrying Out the Invention

[0012] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiments, not all of these plurality of features are essential for the invention, and the plurality of features may be arbitrarily combined. Further, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant descriptions are omitted.

[0013] FIG. 1 is a diagram showing the basic configuration of an imprint apparatus 1 as one aspect of the present invention. The imprint apparatus 1 is a lithography apparatus that is employed in a lithography process, which is a manufacturing process for devices such as semiconductor elements, liquid crystal display elements, and magnetic storage media, and forms a pattern on a substrate. The imprint apparatus 1 forms a pattern of an imprint material on the substrate by molding the imprint material on the substrate using a mold. In the present embodiment, the imprint apparatus 1 brings the imprint material disposed (supplied or applied) on the substrate into contact with the mold, and gives energy for curing to the imprint material, thereby forming a pattern of a cured product in which the pattern of the mold is transferred.

[0014] As the imprint material, a material (curable composition) that cures when energy for curing is applied is used. As the energy for curing, electromagnetic waves, heat, or the like is used. The electromagnetic wave includes, for example, light selected from the range of a wavelength of 10 nm or more and 1 mm or less, specifically, infrared rays, visible rays, ultraviolet rays, and the like.

[0015] The curable composition is a composition that cures by irradiation with light or heating. The photocurable composition that cures by irradiation with light contains at least a polymerizable compound and a photoinitiator, and may further contain a non-polymerizable compound or a solvent as necessary. The non-polymerizable compound is at least one selected from the group consisting of a sensitizer, a hydrogen donor, an internal release agent, a surfactant, an antioxidant, a polymer component, and the like.

[0016] The imprint material may be applied in a film form on the substrate by a spin coater or a slit coater. Further, the imprint material may be applied on the substrate in a droplet form or in an island or film form formed by connecting a plurality of droplets by a liquid injection head. The viscosity of the imprint material (viscosity at 25°C) is, for example, 1 mPa·s or more and 100 mPa·s or less.

[0017] The substrate may be made of glass, ceramics, metal, semiconductor, resin, etc., and may have a member made of a material different from the substrate formed on its surface as needed. Specifically, the substrate may be made of a silicon wafer, a compound semiconductor wafer, quartz glass, etc.

[0018] In this specification and the accompanying drawings, directions are indicated in an XYZ coordinate system, with the direction parallel to the surface on which the substrate is placed being the XY plane. The directions parallel to the X-axis, Y-axis, and Z-axis in the XYZ coordinate system are the X-direction, Y-direction, and Z-direction, respectively, and rotation around the X-axis, Y-axis, and Z-axis are respectively designated as θX, θY, and θZ.

[0019] In this embodiment, the imprint apparatus 1 employs a photo-curing method for curing the imprint material by irradiating it with light such as ultraviolet light. Accordingly, the imprint apparatus 1 performs an imprint process in which a pattern of the imprint material is formed on the substrate by irradiating the imprint material with light while a mold is in contact with the imprint material on the substrate. However, the imprint apparatus 1 can also employ a thermal curing method for curing the imprint material by applying heat.

[0020] 1, the imprint apparatus 1 has an irradiation unit 2, a mold holding unit 3, a mold driving mechanism 22, a substrate stage 4, a dispenser 12, a measurement unit 13, and a control unit 7. The imprint apparatus 1 has a base surface plate 5 that supports the substrate stage 4, a bridge surface plate 6 that supports the mold holding unit 3, and a support column 20 that extends from the base surface plate 5 and supports the bridge surface plate 6 via an anti-vibration unit 21 that reduces vibrations propagating from the floor to the bridge surface plate 6. The imprint apparatus 1 has a substrate transport mechanism 18 that transports a substrate 11 between the substrate stage 4 and the outside of the imprint apparatus 1, and a mold transport mechanism (not shown) that transports a mold 8 between the mold holding unit 3 and the outside of the imprint apparatus 1.

[0021] In the imprinting process, the irradiation unit 2 irradiates the imprint material 19 on the substrate with light 10 for curing the imprint material 19 through the mold 8. The irradiation unit 2 includes, for example, a light source that emits the light 10 and an optical element that adjusts the light 10 from the light source to a state suitable for the imprinting process.

[0022] The mold 8 has, for example, a rectangular outer peripheral shape. The surface of the mold 8 facing the substrate 11 includes a pattern region 9 in which a pattern (such as a circuit pattern) to be formed on the substrate 11 is formed. The mold 8 is made of a material that can transmit the light 10, for example, quartz.

[0023] The mold holding unit 3 is a head having a function of holding the mold 8. The mold holding unit 3 holds the mold 8 by attracting an outer peripheral region, which is a region other than the irradiation surface of the mold 8 irradiated with the light 10, by a vacuum suction force or an electrostatic force. For example, when the mold holding unit 3 holds the mold 8 by a vacuum suction force, a vacuum pump (not shown) installed outside is connected to the mold holding unit 3, and the holding / non-holding (attachment / detachment) of the mold 8 is switched by turning the vacuum pump ON / OFF.

[0024] The mold driving mechanism 22 is a mechanism for bringing the mold 8 into contact with the imprint material 19 on the substrate and separating the mold 8 from the cured imprint material 19 on the substrate by driving the mold holding part 3 holding the mold 8. The mold driving mechanism 22 includes an actuator such as a linear motor or an air cylinder in order to drive the mold holding part 3 (mold 8). The mold driving mechanism 22 may be composed of a plurality of drive systems including a coarse drive system and a fine drive system in order to support highly accurate positioning of the mold 8. The mold driving mechanism 22 may have a function of adjusting not only the Z-direction position of the mold 8 (mold holding part 3 holding the mold 8) but also the X-direction position, the Y-direction position, the rotation and inclination around the Z axis, etc. Note that the operation of bringing the imprint material 19 on the substrate into contact with the mold 8 and the operation of separating the mold 8 from the cured imprint material 19 on the substrate may be realized by driving the substrate stage 4 (substrate 11) in the Z direction. Further, by driving both the mold holding part 3 (mold 8) and the substrate stage 4, the operation of bringing the imprint material 19 on the substrate into contact with the mold 8 and the operation of separating the mold 8 from the cured imprint material 19 on the substrate may be realized.

[0025] The substrate 11 is a substrate onto which the pattern of the mold 8 is transferred. An imprint material 19 that is cured by irradiation with light 10 is disposed on the surface (surface to be processed) of the substrate 11. Specifically, the imprint material 19 is disposed on the surface of the substrate 11 with respect to the imprint region where imprint processing is to be performed.

[0026] The substrate stage 4 is a stage that holds the substrate 11. The substrate stage 4 is used to perform alignment (alignment) between the substrate 11 and the mold 8 when bringing the imprint material 19 on the substrate into contact with the mold 8. The substrate stage 4 includes a substrate holding portion 165 that attracts and holds the substrate 11 by suction force, and an actuator (not shown) that drives the substrate 11 (held by the substrate holding portion 165) in each axial direction. For such an actuator, for example, a linear motor or a planar motor is applied. The substrate stage 4 may be composed of a plurality of drive systems including a coarse drive system and a fine drive system in each of the X-axis and Y-axis directions. Further, the substrate stage 4 may have a function of adjusting not only the positions of the substrate 11 in the X and Y directions but also the position in the Z direction, the rotation around the Z axis, the rotation and inclination around the X and Y axes, etc.

[0027] In the present embodiment, the dispenser 12 is provided in the vicinity of the mold holding portion 3 and has a function of discharging and disposing the uncured imprint material 19 onto the substrate 11 held by the substrate stage 4. The amount of the imprint material 19 supplied from the dispenser 12 to the substrate 11 is determined based on the target film thickness of the imprint material 19 disposed on the substrate and the density of the pattern of the imprint material 19 to be formed on the substrate.

[0028] The measuring unit 13 performs alignment between the substrate 11 and the mold 8. Specifically, it is used to adjust the positional relationship (relative position) between the substrate 11 and the mold 8 and overlay the pattern already formed on the substrate and the pattern of the mold 8 (the pattern to be formed). In the present embodiment, the measuring unit 13 optically detects the overlay pattern already formed on the substrate and the overlay pattern provided on the mold 8, and measures the positional deviation and shape deviation of those overlay patterns.

[0029] The control unit 7 is composed of an information processing device (computer) including a CPU, a memory, and the like. The control unit 7 comprehensively controls each part of the imprinting device 1 according to the program stored in the storage unit to operate the imprinting device 1. The control unit 7 may be configured integrally with the imprinting device 1 (in a common housing), or may be configured separately from the imprinting device 1 (in a separate housing).

[0030] Here, the imprinting process by the imprinting device 1 will be described. Such an imprinting process is performed by the control unit 7 comprehensively controlling each part of the imprinting device 1 for each of a plurality of imprinting areas on the substrate.

[0031] First, the control unit 7 controls the substrate transfer mechanism 18 so that the substrate 11 is transferred to the substrate stage 4 (substrate holding unit 165), and holds the substrate 11 on the substrate stage 4. Next, the control unit 7 drives the substrate stage 4 so that the target imprinting area among the plurality of imprinting areas on the substrate is positioned under the dispenser 12 in order to dispose the imprinting material 19 on the target imprinting area. Then, the control unit 7 controls the dispenser 12 so that the imprinting material 19 is disposed on the target imprinting area on the substrate.

[0032] Next, the control unit 7 drives the substrate stage 4 so that the target imprinting area on the substrate where the imprinting material 19 is disposed is positioned under the mold 8 (pattern area 9 thereof). Then, the control unit 7 drives the mold holding unit 3 via the mold drive mechanism 22 so that the imprinting material 19 on the substrate (on the target imprinting area) comes into contact with the mold 8. As a result, the imprinting material 19 is filled into the pattern formed in the pattern area 9 of the mold 8.

[0033] Next, in a state where the imprinting material 19 on the substrate is in contact with the mold 8, the control unit 7 controls the irradiation unit 2 so that the imprinting material 19 is irradiated with light 10 through the mold 8. As a result, the imprinting material 19 on the substrate cures while being in contact with the mold 8.

[0034] Next, the control unit 7 drives the mold holding unit 3 via the mold drive mechanism 22 so that the mold 8 is separated from the cured imprint material 19 on the substrate. As a result, the pattern of the mold 8 is transferred onto the imprint material 19 on the substrate (on the target imprint area).

[0035] By performing the imprint process including such a series of processes on each of a plurality of imprint areas on the substrate, a pattern of the imprint material 19 (a pattern of the cured product onto which the pattern of the mold 8 is transferred) is formed in each imprint area.

[0036] Hereinafter, a technique regarding the superposition of a pattern already formed on the substrate and the pattern of the mold 8 (the pattern to be formed) will be described.

[0037] First, with reference to FIG. 2, the configuration of the mold 80 in the prior art as the mold 8 applied to the imprint apparatus 1 will be described. As shown in FIG. 2, the pattern area 90 of the pattern surface, which is the surface of the mold 80 facing the substrate 11, includes a main pattern area R1 and a superposition pattern area R2. In the main pattern area R1, a main pattern 15 to be transferred onto the substrate 11, such as a circuit pattern, is formed. In the superposition pattern area R2, a superposition pattern 16 corresponding to the superposition pattern formed on the substrate 11 and a superposition pattern 31 different from the superposition pattern 16 are formed. The superposition pattern 16 is a pattern for aligning with the superposition pattern formed on the substrate 11. The superposition pattern 31 is a pattern for aligning with the substrate 11 when performing the imprint process for forming the second layer.

[0038] In the mold 80 (FIG. 2) in the prior art, when the imprint process for forming the first layer is performed, the overlay pattern on the substrate used (for the overlay pattern 16) becomes a pattern 25 that has been etched away and deformed as shown in FIG. 3(a). Since the pattern 25 is deformed from the original shape of the overlay pattern, it cannot be used for aligning the mold 80 and the substrate 11. Therefore, when performing the imprint process for forming the upper layer 30, which is the second layer, on the substrate 11, as shown in FIG. 3(b), an overlay pattern 26 corresponding to the overlay pattern 31 of the mold 80 needs to be formed on the substrate 11 instead of the pattern 25. As a result, the region where the overlay pattern on the substrate corresponding to the overlay pattern region R2 of the pattern region 90 of the mold 80 (the region where the overlay pattern is formed) becomes wider, and the main pattern region R1 (the region where the main pattern on the substrate is formed) becomes narrower.

[0039] Therefore, in the present embodiment, in order to eliminate the need to form the overlay pattern 26 on the substrate, a technique for protecting the overlay pattern formed on the substrate in the etching process is provided. Specifically, an imprint material 19 pattern that protects (covers) such an overlay pattern is formed on the overlay pattern formed on the substrate. Therefore, in the present embodiment, when forming the imprint material 19 pattern for each of a plurality of imprint regions on the substrate, the imprint process is performed such that the ends of the imprint material 19 patterns formed in adjacent imprint regions slightly overlap. In other words, the imprint material 19 pattern is formed for each of the first imprint region (first region) on the substrate and the second imprint region (second region) including the overlapping region that overlaps the end of the first imprint region.

[0040] <First Embodiment> With reference to FIGS. 4(a), 4(b), and 4(c), as the mold 8 applied to the imprint apparatus 1, the configuration of the mold 50 in the first embodiment and the configuration of the substrate 70 in the first embodiment applied as the substrate 11 will be described.

[0041] As shown in FIG. 4(a), on the surface facing the substrate 70 of the mold 50, a pattern region 51 that contacts the imprint material 19 on the substrate is provided. In this embodiment, the pattern region 51 includes a main pattern region R3, an overlay pattern region R4, and a protection pattern region R5. In the main pattern region R1, for example, a main pattern 52 to be transferred to the substrate 70 (the imprint material 19 on the substrate), such as a circuit pattern, is formed. In the overlay pattern region R4, an overlay pattern 53 for aligning with the overlay pattern 24 formed on the substrate is formed. In the protection pattern region R5, a protection pattern 60 for forming a pattern of the imprint material 19 on top of the overlay pattern 24 formed on the substrate is formed.

[0042] As shown in FIG. 4(b), the main pattern region R3 has a rectangular outer peripheral shape defined by four sides, a first side SD1, a second side SD2, a third side SD3, and a fourth side SD4. The overlay pattern region R4 and the protection pattern region R5 are provided in the peripheral region (peripheral area) of the main pattern region R3. Specifically, the protection pattern region R5 is provided in the peripheral region of the main pattern region R3 along the first side SD1 and the second side SD2 that are adjacent to each other among the four sides defining the outer peripheral shape (rectangle) of the main pattern region R3. The overlay pattern region R4 is provided in the peripheral region of the main pattern region R3 along the third side SD3 and the fourth side SD4 that are opposite to the first side SD1 and the second side SD2 among the four sides defining the outer peripheral shape (rectangle) of the main pattern region R3. Thus, the protection pattern region R5 is provided so as to face the overlay pattern region R4 with the main pattern region R3 in between.

[0043] The overlapping pattern region R4 and the protection pattern region R5 have different structures from each other. This is to make the first pattern (the end part) and the second pattern (the end part) of the imprint material 19 formed by the imprint process for each of the two adjacent imprint regions (the first region and the second region) on the substrate overlap. For example, among the first patterns of the imprint material 19 formed in the imprint process for the first imprint region on the substrate, the pattern (the first part) in the region corresponding to the overlapping pattern region R4 is defined as pattern R4'. Also, among the second patterns of the imprint material 19 formed in the imprint process for the second imprint region adjacent to the first imprint region, the pattern (the second part) in the region corresponding to the protection pattern region R5 is defined as pattern R5'. In the present embodiment, the overlapping pattern region R4 and the protection pattern region R5 have different structures from each other so that the pattern R5' corresponding to the protection pattern region R5 overlaps the pattern R4' corresponding to the overlapping pattern region R4.

[0044] In the protection pattern region R5, as shown by the hatching in FIG. 4(a), the protection pattern 60 is composed of a recess that digs into the surface facing the substrate 70 more than the main pattern region R3, that is, a recess recessed from the main pattern region R3. In the present embodiment, assuming that the depth of the protection pattern 60 (recess) is h1, the depth of the recess forming the main pattern 52 is h2, and the depth of the recess forming the overlapping pattern 53 is h3, each pattern is formed so as to satisfy h1≧h2 and h1>h3. In other words, the depth of the protection pattern 60 (recess) is equal to or greater than the depth of the recess forming the main pattern 52 and deeper than the depth of the recess forming the overlapping pattern 53.

[0045] FIG. 4(c) shows the configuration of the substrate 70 used for the mold 50. As shown in FIG. 4(c), in each of the plurality of imprint regions of the substrate 70, an overlapping pattern 24 is formed at a position facing the overlapping pattern 53 of the mold 50 in the imprint process for each imprint region.

[0046] Using the mold 50, the first pattern and the second pattern of the imprint material 19 formed in each of the adjacent first imprint region and second imprint region on the substrate will be described. Here, in particular, the pattern of the imprint material 19 in the overlapping region between the end of the first imprint region and the end of the second imprint region will be described with attention.

[0047] FIG. 5 is a diagram showing a first pattern 100 of the imprint material 19 formed in a first imprint region on a substrate and a second pattern 101 of the imprint material 19 formed in a second imprint region adjacent to the first imprint region. The first pattern 100 and the second pattern 101 are formed in each imprint region on the substrate by an imprint process using the mold 50. In FIG. 5, an overlapping region R6 is shown as a region where the end of the first imprint region and the end of the second imprint region overlap. Further, an overlapping pattern 24 is formed in the overlapping region R6.

[0048] Referring to FIG. 5, in the overlapping region R6, a first portion 111 of the first pattern 100 and a second portion 110 of the second pattern 101 overlap. Note that the first portion 111 corresponds to a pattern R4' in a region corresponding to the overlapping pattern region R4 of the first pattern 100. The second portion 110 corresponds to a pattern R5' in a region corresponding to the protection pattern region R5 of the second pattern 101. Thus, the protection pattern 60 of the mold 50 forms a second portion 110 of the second pattern 101 that covers the first portion 111 of the first pattern 100 on the overlapping pattern 24 formed in the overlapping region R6 in the imprint process for the second imprint region. In other words, the main pattern of the first pattern 100 is formed in the central region of the first imprint region, and the second portion 110 of the second pattern 101 is formed in the peripheral region (overlapping region R6) around the central region of the first imprint region.

[0049] Further, the main pattern corresponding to the main pattern 52 of the type 50 of the first pattern 101 is formed in the central region of the first imprint region. In this case, it can be said that the second portion 110 of the second pattern 101 is formed in the peripheral region (the overlapping region R6 which is the end of the first imprint region and the second imprint region) around the central region of the first imprint region.

[0050] Here, let the remaining film thickness of the first pattern 100 and the second pattern 101 formed by the imprint process be h5. Also, let the height of the second portion 110 (pattern R5') of the second pattern 101 be h1', and the height of the main pattern 112 corresponding to the main pattern 52 of the type 50 in the second pattern 101 be h2'. Further, let the height of the first portion 111 (pattern R4') of the first pattern 100, specifically, the height of the pattern corresponding to the overlapping pattern 53 of the type 50 in the first pattern 100 be h3'.

[0051] In this embodiment, the total value of the height h1' of the second portion 110 and the remaining film thickness h5 is made larger than the total value of the height h3' of the first portion 111 and the remaining film thickness h5. In other words, the height h1' of the second portion 110 is made higher than the height h3' of the first portion 111. Thereby, in the imprint process for the second imprint region adjacent to the first imprint region, it is possible to suppress the type 50 from contacting and damaging the first portion 111 of the first pattern 100 formed in the first imprint region.

[0052] Also, in the present embodiment, the sum of the height h1' of the second portion 110 and the remaining film thickness h5 is made the same as, or greater than, the sum of the height h2' of the main pattern 112 of the second pattern 101 and the remaining film thickness h5. In other words, in the second pattern 101, the height of the second portion 110 is made equal to or greater than the height of the main pattern 112. Thus, in the present embodiment, the second pattern 101 is formed such that the total film thickness of the pattern (the first portion 111 and the second portion 110) of the imprint material 19 formed in the overlapping region R6 is greater than the total film thickness of the main pattern 112 of the second pattern 101. Thereby, when transferring the main pattern 112 of the second pattern 101 to the substrate 70 by an etching process, it is possible to suppress the overlapping pattern 24 formed on the substrate 70 from being scraped and deformed.

[0053] Thus, in the present embodiment, it is possible to protect the overlapping pattern 24 formed on the substrate, and when performing an imprint process for forming an upper layer on the first pattern 100 and the second pattern 101, the overlapping pattern 24 can be reused. Therefore, on the substrate, it is not necessary to form an overlapping pattern 26 separately from the overlapping pattern 24, and since it is not necessary to form an overlapping pattern 31 corresponding to the overlapping pattern 26 in the mold 80, the main pattern region R3 of the mold 80 can be widened.

[0054] In the present embodiment, it has been described that the sum of the height h1' of the second portion 110 of the second pattern 101 and the remaining film thickness h5 is made greater than or equal to the sum of the height h2' of the main pattern 112 of the second pattern 101 and the remaining film thickness h5. However, in actuality, the height h1' of the second portion 110 of the second pattern 101 only needs to have a height that does not deform the overlapping pattern 24 formed on the substrate.

[0055] Hereinafter, with reference to FIGS. 6 and 7, the sequence of the imprint process in the first embodiment will be described. In this embodiment, when forming the pattern of the imprint material 19 for each of the plurality of imprint regions on the substrate, the imprint process is performed such that the ends of the patterns of the imprint material 19 formed in adjacent imprint regions slightly overlap. Specifically, as described above, using the imprint apparatus 1 to which the mold 50 is applied, the second portion 110 of the second pattern 101 is formed on the first portion 111 of the first pattern 100 for all the imprint regions on the substrate. In this embodiment, the imprint process is performed on the plurality of imprint regions on the substrate in the order shown in FIG. 6, for example.

[0056] FIG. 7 is a flowchart for explaining the imprint process in the first embodiment. Such an imprint process is performed by the control unit 7 comprehensively controlling each part of the imprint apparatus 1 as described above.

[0057] In S100, the imprint material 19 is disposed by the dispenser 12 in the first imprint region, which is the target of the imprint process, among the plurality of imprint regions on the substrate 70.

[0058] In S101, the imprint material 19 disposed in the first imprint region is brought into contact with the mold 50 (the pattern region 51 thereof). Specifically, the substrate stage 4 is driven so that the first imprint region where the imprint material 19 is disposed is located under the mold 50, and the imprint material 19 on the first imprint region and the mold 50 are brought into contact with each other by the mold driving mechanism 22. As a result, the pattern region 51 of the mold 50 is filled with the imprint material 19.

[0059] In S102, alignment between the substrate 70 and the mold 50 is performed. Specifically, the measurement unit 13 measures the relative positions of the overlay pattern 24 formed on the substrate 70 (the overlapping region R6 between the first shot region and the second shot region) and the overlay pattern 53 provided on the mold 50. Then, based on the relative positions measured by the measurement unit 13, the substrate stage 4 is driven to align the first imprint region of the substrate 70 and the pattern region 51 of the mold 50. Thus, S102 is also a process (the first alignment process) of aligning the substrate 70 in order to adjust the position where the first pattern 100 is formed in the first imprint region.

[0060] In S103, with the imprint material 19 disposed in the first imprint region in contact with the mold 50, the imprint material 19 is cured. Specifically, the irradiation unit 2 irradiates light through the mold 50 onto the imprint material 19 to cure the imprint material 19 disposed in the first imprint region.

[0061] In S104, demolding is performed. Specifically, the mold driving mechanism 22 separates the mold 50 from the cured imprint material 19 on the first imprint region.

[0062] In S105, among the plurality of imprint regions of the substrate 70, the dispenser 12 disposes the imprint material 19 in the second imprint region adjacent to the first imprint region, which is the target of the imprint process.

[0063] In S106, the imprint material 19 disposed in the second imprint region is brought into contact with the mold 50 (the pattern region 51 thereof). Specifically, the substrate stage 4 is driven so that the second imprint region where the imprint material 19 is disposed is positioned under the mold 50, and the mold driving mechanism 22 brings the imprint material 19 on the second imprint region into contact with the mold 50. As a result, the pattern region 51 of the mold 50 is filled with the imprint material 19.

[0064] In S107, alignment between the substrate 70 and the mold 50 is performed. Specifically, the measurement unit 13 measures the relative position between the overlay pattern 24 formed on the substrate 70 (the overlapping region between the second shot region and the third shot region adjacent to the second shot region) and the overlay pattern 53 provided on the mold 50. Then, based on the relative position measured by the measurement unit 13, the substrate stage 4 is driven to align the second imprint region of the substrate 70 and the pattern region 51 of the mold 50. As a result, the overlay pattern 24 formed in the overlapping region R6 and the protection pattern 60 of the mold 50 overlap. Thus, S107 is also a step (second alignment step) of aligning the substrate 70 in order to adjust the position where the second pattern 101 is formed in the second imprint region.

[0065] In S108, with the imprint material 19 disposed in the second imprint region in contact with the mold 50, the imprint material 19 is cured. Specifically, the irradiation unit 2 irradiates light through the mold 50 to the imprint material 19 to cure the imprint material 19 disposed in the second imprint region.

[0066] In S109, demolding is performed. Specifically, the mold driving mechanism 22 separates the mold 50 from the cured imprint material 19 on the second imprint region.

[0067] In this way, the first pattern 100 and the second pattern 101 of the imprint material 19 are formed in the first imprint region and the second imprint region of the substrate 70, respectively. Then, S105 to S109 are repeated to perform imprinting on all the imprint regions of the substrate 70. As a result, a pattern (the second portion 110 of the second pattern 101) of the imprint material 19 that protects the superposition pattern 24 can be formed on the superposition pattern 24 formed in each imprint region of the substrate 70. Therefore, it is possible to suppress the superposition pattern 24 formed on the substrate 70 from being etched and deformed, and the superposition pattern 24 can be reused when forming the upper layer. This contributes to reducing the area of the superposition pattern 24 formed on the substrate 70.

[0068] <Second Embodiment> In the first embodiment, the alignment with the substrate 70 is performed by providing the superposition pattern 53 in the peripheral region along two adjacent sides among the four sides defining the rectangular outer peripheral shape of the main pattern region R3 of the mold 80. However, by providing the superposition pattern 53 in the peripheral region of the entire circumference of the main pattern region R3 of the mold 50, the superposition accuracy can be improved, and alignment can be performed even when the imprint region is narrow on the outer periphery of the substrate 70. Therefore, in the second embodiment, a technique is provided that can protect the superposition pattern on the substrate and provide the superposition pattern on the entire circumference of the imprint region.

[0069] Referring to FIGS. 8(a) and 8(b), the configuration of the mold 150 in the second embodiment and the configuration of the substrate 211 in the second embodiment applied as the substrate 11 will be described as the mold 8 applied to the imprint apparatus 1. Note that the configuration of the mold 150 not described in this embodiment is the same as that of the mold 50.

[0070] As shown in FIG. 8(a), in the present embodiment, the pattern region 51 provided on the surface facing the substrate 211 of the mold 150 includes a main pattern region R3, an overlapping pattern region R4, a protection pattern region R5, and an overlapping pattern region R7. In the overlapping pattern region R7, an overlapping pattern 154 for aligning with the overlapping pattern 24 formed on the substrate is formed. The overlapping pattern region R7 is provided in the peripheral region between the main pattern region R3 and the protection pattern region R5 along the first side SD1 and the second side SD2 among the four sides defining the rectangular outer peripheral shape of the main pattern region R3. Therefore, the overlapping patterns 53 and 154 are formed in the peripheral region of the entire circumference of the main pattern region R3 of the mold 150.

[0071] In the present embodiment, the recesses constituting the protection pattern 60 extend to the overlapping pattern region R7 as shown in FIG. 8(a). In other words, the overlapping pattern region R7 is constituted by a recess that digs into the surface facing the substrate 70 more than the main pattern region R3, and the overlapping pattern 154 is constituted by a recess formed in the recess. Therefore, the depth h4 of the overlapping pattern region R7 (recess) is deeper than the depth h2 of the recess constituting the main pattern 52.

[0072] Thus, in the present embodiment, the mold 150 has a structure in which an overlapping region R7 is provided outside the main pattern region R3, and a protection pattern region R5 (protection pattern 60) is further provided outside. Thereby, as shown in FIG. 8(b), alignment can be performed on the entire circumference of the imprint region using the substrate 211 provided with the overlapping pattern 24 on the entire circumference of each imprint region.

[0073] FIG. 9 is a diagram showing a first pattern 100 of an imprint material 19 formed in a first imprint region on a substrate and a second pattern 101 of the imprint material 19 formed in a second imprint region adjacent to the first imprint region. The first pattern 100 and the second pattern 101 are formed in each imprint region on the substrate by an imprint process using a mold 150. Similar to the first embodiment, an overlay pattern 24 formed in an overlapping region R6 between the first imprint region and the second imprint region is protected by a first portion 111 of the first pattern 100 and a second portion 110 of the second pattern 101.

[0074] In the present embodiment, a pattern in a region corresponding to an overlay pattern region R7 among the second patterns 101 of the imprint material 19 formed in the imprint process for the second imprint region on the substrate is defined as a third portion 113. In the overlay pattern region R7, the sum of the height h4' of the third portion 113 of the second pattern 101 and the remaining film thickness h5 is made the same as, or larger than, the sum of the height h2' of the main pattern 112 of the second pattern 101 and the remaining film thickness h5. In other words, in the second pattern 101, the height of the third portion 113 is made equal to or greater than the height of the main pattern 112. Thus, in the present embodiment, the second pattern 101 is formed such that the total film thickness of the pattern (third portion 113) of the imprint material 19 formed in the overlay pattern region R7 is larger than the total film thickness of the main pattern 112 of the second pattern 101. Thereby, it is possible to suppress the overlay pattern 24 formed on the substrate 211 from being scraped and deformed when transferring the main pattern 112 of the second pattern 101 to the substrate 70 by an etching process.

[0075] The sequence of the imprint process in the second embodiment is basically the same as that in the first embodiment, except that the alignment between the substrate 211 and the mold 150 in S107 is different. In this embodiment, in S107, not only the overlay pattern 24 formed in the overlay region R4 but also the overlay pattern 24 formed in the overlay pattern region R7 is used to align the substrate 211 and the mold 150. Therefore, in this embodiment, compared with the first embodiment, the alignment accuracy between the substrate 211 and the mold 150, that is, the overlay accuracy between the pattern already formed on the substrate and the pattern to be formed can be improved.

[0076] <Third Embodiment> In the second embodiment, in order to realize the die-by-die method, it is necessary to form the overlay pattern 24 for each imprint area on the substrate. In the third embodiment, the area (total area) of the overlay pattern 24 formed on the substrate is reduced by sharing the overlay pattern 24 in adjacent imprint areas on the substrate.

[0077] Referring to FIGS. 10(a) and 10(b), the configuration of the mold 250 in the third embodiment and the configuration of the substrate 311 in the third embodiment applied as the substrate 11 will be described as the mold 8 applied to the imprint apparatus 1. Note that the configuration of the mold 250 not described in this embodiment is the same as that of the mold 50.

[0078] As shown in FIG. 10(a), the pattern area 51 provided on the surface of the mold 250 facing the substrate 311 includes, in this embodiment, the main pattern area R3, the overlay pattern area R4, and the protection pattern area R5. In this embodiment, in addition to the protection pattern 60, an overlay pattern 254 for aligning with the overlay pattern 24 formed on the substrate is formed in the protection pattern area R5. The overlay pattern 254 is composed of recesses formed in the recesses constituting the protection pattern 60 directly above the protection pattern 60.

[0079] In this embodiment, as shown in FIG. 10(b), the overlay pattern 24 formed on the outer periphery of each imprint region of the substrate 311 is shared by adjacent imprint regions in the alignment of the substrate 311 and the mold 250. Thereby, compared with the second embodiment, the area of the overlay pattern 24 formed on the substrate 311 can be reduced, and the area where the main pattern is formed can be increased.

[0080] FIG. 11 is a diagram showing a first pattern 100 of the imprint material 19 formed in the first imprint region on the substrate, and a second pattern 101 of the imprint material 19 formed in the second imprint region adjacent to the first imprint region. The first pattern 100 is aligned with the overlay pattern 24 formed on the substrate 311, and the first portion 111 used for the alignment is formed on the overlay pattern 24.

[0081] When an imprint process is performed on the second imprint region adjacent to the first imprint region using the mold 250, the imprint material 19 is filled between the substrate 311 and the mold 250. Since the first pattern 100 formed in the first imprint region and the imprint material 19 disposed in the second imprint region are made of the same material and have the same refractive index, the boundary therebetween cannot be optically detected by the measuring unit 13. Therefore, in the overlapping region R6, the relative positions of the overlay pattern 24 on the substrate and the overlay pattern 254 of the mold 250 can be measured by the measuring unit 13 without being obstructed by the first portion 111 of the first pattern 100.

[0082] The sequence of the imprint process in the third embodiment is basically the same as that in the first embodiment, except that the alignment between the substrate 211 and the mold 150 in S107 is different. In S107, the measurement unit 13 measures the relative positions of the superposition pattern 24 formed on the substrate 311, the superposition patterns 53 and 254 provided on the mold 250. Then, based on the relative positions of the superposition pattern 24 measured by the measurement unit 13 and the superposition patterns 53 and 254, the substrate stage 4 is driven to align the second imprint region of the substrate 70 and the pattern region 51 of the mold 50. As described above, by S100 to S104, the first portion 111 of the first pattern 100 is formed on the superposition pattern 24 formed in the overlapping region R6 of the substrate 311. However, in S105, the imprint material 19 is filled between the first portion 111 of the first pattern 100 and the pattern region 51 of the mold 250, specifically, the protection pattern region R5. Thereby, in the overlapping region R6, it becomes possible to measure the relative positions of the superposition pattern 24 and the superposition pattern 254 without being inhibited by the first portion 111. In other words, in S102 (the first alignment step) and S107 (the second alignment step), the substrate 311 can be aligned using the same superposition pattern 24 formed on the substrate 311.

[0083] The pattern of the cured product formed using the imprint apparatus 1 in this embodiment is used permanently for at least a part of various articles, or temporarily when manufacturing various articles. The articles include electric circuit elements, optical elements, MEMS, recording elements, sensors, or molds. Examples of the electric circuit elements include volatile or non-volatile semiconductor memories such as DRAM, SRAM, flash memory, and MRAM, and semiconductor elements such as LSI, CCD, image sensors, and FPGA. Examples of the molds include molds for imprinting.

[0084] The pattern of the cured material is used as it is as at least a part of the constituent members of the above-described article, or is temporarily used as a resist mask. After etching, ion implantation, etc. are performed in the substrate processing step, the resist mask is removed.

[0085] Next, a specific manufacturing method of the article will be described. As shown in Fig. 12(a), a substrate such as a silicon wafer on which a material to be processed such as an insulator is formed on the surface is prepared, and subsequently, an imprint material is applied to the surface of the material to be processed by an inkjet method or the like. Here, a state where a plurality of droplet-shaped imprint materials are applied on the substrate is shown.

[0086] As shown in Fig. 12(b), the imprint mold is opposed with the side on which the concavo-convex pattern is formed facing the imprint material on the substrate. As shown in Fig. 12(c), the substrate on which the imprint material is applied and the mold are brought into contact with each other and pressure is applied. The imprint material is filled in the gap between the mold and the material to be processed. When light is irradiated through the mold as energy for curing in this state, the imprint material cures.

[0087] As shown in Fig. 12(d), after curing the imprint material and separating the mold and the substrate, a pattern of the cured product of the imprint material is formed on the substrate. The pattern of this cured product has a shape in which the concave portion of the mold corresponds to the convex portion of the cured product and the convex portion of the mold corresponds to the concave portion of the cured product, that is, the concavo-convex pattern of the mold is transferred to the imprint material.

[0088] As shown in Fig. 12(e), when etching is performed using the pattern of the cured product as an etching-resistant mask, the portion of the surface of the material to be processed where there is no cured product or where a thin residue remains is removed and becomes a groove. As shown in Fig. 12(f), when the pattern of the cured product is removed, an article having grooves formed on the surface of the material to be processed can be obtained. Here, the pattern of the cured product is removed, but it may not be removed after processing and may be used as a film for interlayer insulation included in a semiconductor element or the like, that is, as a constituent member of the article.

[0089] The disclosure of this specification includes the following imprinting methods, molds, imprinting apparatuses, and article manufacturing methods.

[0090] (Item 1) An imprinting method of forming a pattern of an imprinting material in each of a first region on a substrate and a second region including an overlapping region overlapping an end of the first region, a first step of forming a first pattern of the imprinting material including a first portion formed on the overlapping pattern formed in the overlapping region and a main pattern in the first region; a second step of forming a second pattern of the imprinting material including a second portion covering the first portion of the first pattern and a main pattern in the second region; In the second step, the second pattern is formed such that a total film thickness of the pattern of the imprinting material formed in the overlapping region is greater than a total film thickness of the main pattern of the second pattern. An imprinting method characterized by the above.

[0091] (Item 2) The height of the second portion of the second pattern is equal to or greater than the height of the main pattern of the second pattern. The imprinting method according to Item 1, characterized by the above.

[0092] (Item 3) The height of the second portion of the second pattern is higher than the height of the first portion of the first pattern. The imprinting method according to Item 1 or 2, characterized by the above.

[0093] (Item 4) The main pattern of the first pattern is formed in a central region of the first region, The second portion of the second pattern is formed in a peripheral region around the central region of the first region. The imprinting method according to any one of Items 1 to 3, characterized by the above.

[0094] (Item 5) The first step includes a first alignment step of aligning the substrate to adjust the position where the first pattern is formed in the first region. The second step includes a second alignment step of aligning the substrate to adjust the position where the second pattern is formed in the second region. In the first alignment step and the second alignment step, the substrate is aligned using the same overlapping pattern formed on the substrate. The imprint method according to any one of Items 1 to 4, characterized in that.

[0095] (Item 6) A mold for forming a pattern of an imprint material on a substrate, It has a pattern region provided on the surface facing the substrate and in contact with the imprint material, The pattern region includes a main pattern region in which a main pattern to be transferred to the imprint material is formed, and a protection pattern region provided around the main pattern region and formed with a protection pattern for forming the pattern of the imprint material on the overlapping pattern formed on the substrate. The protection pattern is composed of recesses recessed from the main pattern region. A mold characterized in that.

[0096] (Item 7) The mold according to Item 6, characterized in that the depth of the recess is equal to or greater than the depth of the recess constituting the main pattern.

[0097] (Item 8) The main pattern region has a rectangular outer peripheral shape, The protection pattern region is provided in a region around the main pattern region along a first side and a second side that are adjacent to each other among the four sides defining the rectangle. The mold according to Item 6 or 7, characterized in that.

[0098] (Item 9) The pattern region further includes an alignment pattern region on which an alignment pattern for aligning with an alignment pattern formed on the substrate is formed. The alignment pattern region is provided in a region around the main pattern region along the third side and the fourth side facing the first side and the second side among the four sides. The mold according to item 8, characterized in that.

[0099] (Item 10) The pattern region further includes an alignment pattern region on which an alignment pattern for aligning with an alignment pattern formed on the substrate is formed. The alignment pattern region is provided in a region between the main pattern region and the protection pattern region. The mold according to item 6 or 7, characterized in that.

[0100] (Item 11) The recesses constituting the protection pattern extend to the alignment pattern region. The alignment pattern formed in the alignment pattern region is composed of recesses formed in the recesses. The mold according to item 10, characterized in that.

[0101] (Item 12) An alignment pattern for aligning with an alignment pattern formed on the substrate is also formed in the protection pattern region. The alignment pattern formed in the protection pattern region is composed of recesses formed in the recesses. The mold according to item 6 or 7, characterized in that.

[0102] (Item 13) An imprint apparatus for forming a pattern of an imprint material on a substrate using a mold, having a mold holding portion for holding the mold. The type includes the type described in any one of items 6 to 12. An imprint apparatus characterized by the above.

[0103] (Item 14) A step of forming a pattern on a substrate using the imprint method described in any one of items 1 to 5; A step of processing the substrate on which the pattern has been formed in the above step; A step of manufacturing an article from the processed substrate; A method for manufacturing an article, characterized by including the above steps.

[0104] The invention is not limited to the above embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Therefore, claims are attached to disclose the scope of the invention.

Explanation of Reference Numerals

[0105] 1: Imprint apparatus 24: Overlay pattern 50: Mold 52: Main pattern 53: Overlay pattern 60: Protection pattern 70: Substrate 100: First pattern 101: Second pattern 110: Second part 111: First part

Claims

1. An imprinting method for forming a pattern of an imprint material on each of a first region on a substrate and a second region including an overlapping region overlapping an end of the first region, comprising: a first step of forming a first pattern of the imprint material including a first portion formed on the overlapping pattern formed in the overlapping region and a main pattern in the first region; a second step of forming a second pattern of the imprint material including a second portion covering the first portion of the first pattern and a main pattern in the second region; In the second step, the second pattern is formed such that the total film thickness of the pattern of the imprint material formed in the overlapping region is greater than the total film thickness of the main pattern of the second pattern. An imprinting method characterized by the above.

2. The height of the second portion of the second pattern is equal to or greater than the height of the main pattern of the second pattern. The imprinting method according to claim 1, characterized by the above.

3. The height of the second portion of the second pattern is higher than the height of the first portion of the first pattern. The imprinting method according to claim 1, characterized by the above.

4. The main pattern of the first pattern is formed in the central region of the first region, The second portion of the second pattern is formed in a peripheral region around the central region of the first region. The imprinting method according to claim 1, characterized by the above.

5. The first step includes a first alignment step of aligning the substrate to adjust the position where the first pattern is formed in the first region, The second step includes a second alignment step of aligning the substrate to adjust the position where the second pattern is formed in the second region, In the first alignment step and the second alignment step, the substrate is aligned using the same overlapping pattern formed on the substrate. The imprinting method according to claim 1, characterized by the above.

6. A mold for forming a pattern of an imprint material on a substrate, having a pattern region provided on a surface facing the substrate and contacting the imprint material. The pattern area includes a main pattern area in which a main pattern to be transferred to the imprint material is formed, and a protection pattern area provided around the main pattern area and formed on the superposition pattern formed on the substrate for forming a pattern of the imprint material on the superposition pattern. The protection pattern is composed of recesses recessed from the main pattern area. A mold characterized by this.

7. The mold according to claim 6, wherein a depth of the recess is equal to or greater than a depth of a recess forming the main pattern.

8. The main pattern area has a rectangular outer peripheral shape. The protection pattern area is provided in an area around the main pattern area along a first side and a second side that are adjacent to each other among the four sides defining the rectangle. The mold according to claim 6, characterized by this.

9. The pattern area further includes a superposition pattern area in which a superposition pattern for aligning with the superposition pattern formed on the substrate is formed. The superposition pattern area is provided in an area around the main pattern area along a third side and a fourth side that face the first side and the second side among the four sides. The mold according to claim 8, characterized by this.

10. The pattern area further includes a superposition pattern area in which a superposition pattern for aligning with the superposition pattern formed on the substrate is formed. The superposition pattern area is provided in an area between the main pattern area and the protection pattern area. The mold according to claim 6, characterized by this.

11. The recess forming the protection pattern extends to the superposition pattern area. The superposition pattern formed in the superposition pattern area is composed of recesses formed in the recess. The mold according to claim 10, characterized by this.

12. A superposition pattern for aligning with the superposition pattern formed on the substrate is also formed in the protection pattern area. The superposition pattern formed in the protection pattern area is composed of recesses formed in the recess. The mold according to claim 6, characterized by this.

13. An imprint apparatus for forming a pattern of an imprint material on a substrate using a mold, It has a mold holding part for holding the mold, The mold includes the mold according to claim 6, An imprint apparatus characterized by the above.

14. A step of forming a pattern on a substrate using the imprint method according to claim 1, A step of processing the substrate on which the pattern is formed in the above step, A step of manufacturing an article from the processed substrate, A method for manufacturing an article, characterized by comprising the above steps.

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