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

Abstract

The present disclosure relates to an imprint method of forming a pattern in an imprint material disposed on each of a first region and a second region on a substrate, the second region including an overlapping region overlapping an edge of the first region, the imprint method comprising: forming a first pattern in the imprint material on the first region, the first pattern includes a main pattern and a first portion formed on an overlapping pattern formed in an overlapping region; and forming a second pattern in the imprint material on the second region, the second pattern including a main pattern and a second portion covering the first portion of the first pattern, in which when the second pattern is formed, the second pattern is formed such that a film thickness of the pattern formed in the overlapping region is greater than a film thickness of the main pattern of the second pattern. The present disclosure also relates to a mold for forming a pattern in an imprint material on a substrate, an imprint apparatus for forming a pattern in an imprint material on a substrate by using the mold, and an article manufacturing method.

Description

Technical Field

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

[0002] In the manufacturing steps of semiconductor elements, MEMS, etc., an imprinting apparatus is used. The imprinting apparatus forms a predetermined pattern by disposing an imprinting material (a liquid fluid including uncured resin, etc.) on a substrate and pressing (contacting) a mold having concavo-convex processing against the imprinting material. The imprinting apparatus optically detects overlapping patterns respectively provided on the mold and the substrate, thereby achieving high-precision overlapping between the mold and the substrate. Therefore, the imprinting apparatus can form a pattern having a fine structure on the order of several nanometers on the substrate.

[0003] Regarding the imprinting apparatus, Japanese Patent Application Laid-Open No. 2014-175620 proposes a technique for preventing the formation of a region without an imprinting material, that is, preventing the formation of a gap between a plurality of imprinting regions (target regions) on a substrate on which an imprinting process is performed. Japanese Patent Application Laid-Open No. 2014-175620 discloses a method in which an imprinting process is performed on each imprinting region so as to overlap the outer peripheral portion (edge) of an adjacent imprinting region on the substrate.

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

[0005] However, since the overlapping pattern on the substrate used when performing the imprinting process of the first layer is cut and deformed by an etching process, it cannot be used for the imprinting process of the second layer and subsequent layers. Therefore, in order to perform the imprinting process of the second layer and subsequent layers, an overlapping pattern available for the second layer must be provided in a region different from the overlapping pattern used for the first layer. This increases the region for forming the overlapping pattern on the substrate. Summary of the Invention

[0006] The present invention provides a technique that is advantageous for protecting an overlapping pattern formed on a substrate, thereby reducing the region for forming the overlapping pattern.

[0007] According to a first aspect of the present invention, there is provided an imprinting method for forming a pattern in an imprinting material on each of a first region and a second region disposed on a substrate, the second region including an overlapping region overlapping with an edge of the first region, the imprinting method including: forming a first pattern in the imprinting material on the first region, the first pattern including a main pattern and a first portion formed on an overlapping pattern formed in the overlapping region; and forming a second pattern in the imprinting material on the second region, the second pattern including a main pattern and a second portion covering the first portion of the first pattern, wherein when forming the second pattern, the second pattern is formed such that a film thickness of a pattern formed in the overlapping region is greater than a film thickness of the main pattern of the second pattern.

[0008] According to a second aspect of the present invention, there is provided a mold for forming a pattern in an imprinting material on a substrate, the mold including a substrate, and a pattern region provided on a surface of the substrate facing the substrate and in contact with the imprinting material, wherein the pattern region includes: a main pattern region in which a main pattern to be transferred to the imprinting material is formed; and a protection pattern region provided around the main pattern region and formed with a protection pattern for forming a pattern in the imprinting material on an overlapping pattern formed on the substrate, and the protection pattern includes a recess recessed from the main pattern region.

[0009] According to a third aspect of the present invention, there is provided an imprinting apparatus for forming a pattern in an imprinting material on a substrate by using a mold, the imprinting apparatus including a mold holding unit configured to hold the mold, and a substrate holding unit configured to hold the substrate, wherein the mold includes the above-described mold.

[0010] According to a fourth aspect of the present invention, there is provided an article manufacturing method, the article manufacturing method including a forming step of forming a pattern on a substrate by using the above-described imprinting method, processing the substrate on which the pattern is formed in the forming step, and manufacturing an article from the processed substrate.

[0011] Other aspects of the present invention will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings. Description of the Drawings

[0012] Figure 1 is a schematic view showing a basic configuration of an imprinting apparatus according to an aspect of the present invention.

[0013] Figure 2 is a view showing a configuration of a mold in the conventional art.

[0014] Figure 3A andFigure 3B It is a view for describing the conventional technology.

[0015] Figures 4A to 4C It is a view for describing the structure of the mold and the structure of the substrate in the first embodiment.

[0016] Figure 5 It is a view showing the first pattern and the second pattern respectively formed in the first imprinting area and the second imprinting area.

[0017] Figure 6 It is a view showing an example of the order of the imprinting process for a plurality of imprinting areas on the substrate.

[0018] Figure 7 It is a flowchart for describing the imprinting process in the first embodiment.

[0019] Figure 8A and Figure 8B It is a view for describing the structure of the mold and the structure of the substrate in the second embodiment.

[0020] Figure 9 It is a view showing the first pattern and the second pattern respectively formed in the first imprinting area and the second imprinting area.

[0021] Figure 10A and Figure 10B It is a view for describing the structure of the mold and the structure of the substrate in the third embodiment.

[0022] Figure 11 It is a view showing the first pattern and the second pattern respectively formed in the first imprinting area and the second imprinting area.

[0023] Figures 12A to 12F It is a view for describing the method of manufacturing an article. Detailed Description of the Invention

[0024] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. It should be noted that the following embodiments are not intended to limit the scope of the claimed invention. In the embodiments, a plurality of features are described, but the invention is not limited to requiring all such features, and a plurality of such features can be appropriately combined. In addition, in the drawings, the same reference numerals are given to the same or similar structures, and redundant descriptions thereof are omitted.

[0025] Figure 1FIG. 0 is a schematic view showing the basic configuration of an imprint apparatus 1 according to an aspect of the present invention. The imprint apparatus 1 is a lithographic apparatus used in a lithography step for forming a pattern on a substrate, and the lithography step is a manufacturing step for devices such as semiconductor elements, liquid crystal display elements, or magnetic storage media. 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 this embodiment, the imprint apparatus 1 brings the imprint material disposed (supplied or applied) on the substrate into contact with the mold and applies curing energy to the imprint material, thereby forming a pattern of a cured product on which the mold pattern is transferred.

[0026] As the imprint material, a material (curable composition) that cures by receiving curing energy is used. Examples of the curing energy used are electromagnetic waves, heat, etc. As the electromagnetic wave, for example, infrared light, visible light, ultraviolet light, etc. selected from the wavelength range of 10 nm (inclusive) to 1 mm (inclusive) are used.

[0027] The curable composition is a composition that cures by light irradiation or heating. The photocurable composition that cures by light irradiation contains at least a polymerizable compound and a photoinitiator, and may contain a non-polymerizable compound or a solvent as needed. The non-polymerizable compound is at least one type of material selected from the group consisting of a sensitizer, a hydrogen donor, an internal release agent, a surfactant, an antioxidant, a polymer component, etc.

[0028] The imprint material can be applied to the substrate in a thin film shape by a spin coater or a slit coater. The imprint material can be applied to the substrate in a droplet shape or in an island shape or a thin film shape formed by connecting a plurality of droplets using a liquid ejection head. The viscosity of the imprint material (viscosity at 25°C) is, for example, 1 mPa·s (inclusive) to 100 mPa·s (inclusive).

[0029] As the substrate, glass, ceramic, metal, semiconductor, resin, etc. are used, and a member made of a material different from the substrate can be formed on the surface of the substrate as needed. More specifically, examples of the substrate include a silicon wafer, a semiconductor compound wafer, quartz glass, etc.

[0030] In the specification and the drawings, directions will be indicated on an XYZ coordinate system, where the direction parallel to the plane on which the substrate is placed is defined as the X-Y 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. The rotation around the X axis, the rotation around the Y axis, and the rotation around the Z axis are θX, θY, and θZ, respectively.

[0031] In this embodiment, as a method for curing an imprint material, the imprint apparatus 1 employs a photocuring method in which the imprint material is cured by irradiation with light such as ultraviolet light. Thus, the imprint apparatus 1 performs an imprint process in which, with the mold in contact with the imprint material on the substrate, a pattern of the imprint material is formed on the substrate by irradiating the imprint material with light. However, as a method for curing the imprint material, the imprint apparatus 1 may employ a thermal curing method in which the imprint material is cured by applying heat.

[0032] As Figure 1 shown, the imprint apparatus 1 includes 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 includes a base plate 5 that supports the substrate stage 4, a bridge plate 6 that supports the mold holding unit 3, and a column 20 that extends from the base plate 5 and supports the bridge plate 6 via a vibration isolator 21 that reduces vibrations transmitted from the floor to the bridge plate 6. The imprint apparatus 1 includes a substrate transfer mechanism 18 and a mold transfer mechanism (not shown), the substrate transfer mechanism 18 transferring the substrate 11 between the substrate stage 4 and the outside of the imprint apparatus 1, and the mold transfer mechanism transferring the mold 8 between the mold holding unit 3 and the outside of the imprint apparatus 1.

[0033] In the imprint process, the irradiation unit 2 irradiates the imprint material 19 on the substrate with light 10 via the mold 8 to cure the imprint material 19. 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 imprint process.

[0034] The mold 8 has an outer peripheral shape such as a rectangle, for example. 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 (such as quartz) that can transmit the light 10.

[0035] 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 other than the irradiated surface of the mold 8 that is irradiated with the light 10 by vacuum attraction or electrostatic force. For example, if the mold holding unit 3 holds the mold 8 by vacuum attraction, the mold holding unit 3 is connected to a vacuum pump (not shown) installed outside, and the holding / non-holding (attachment / detachment) of the mold 8 is switched by turning on / off (ON / OFF) the vacuum pump.

[0036] The mold driving mechanism 22 is a mechanism that drives the mold holding unit 3 holding the mold 8 to perform an operation of bringing the mold 8 into contact with the imprint material 19 on the substrate and an operation of separating the mold 8 from the cured imprint material 19 on the substrate. The mold driving mechanism 22 includes, for example, an actuator such as a linear motor or a cylinder for driving the mold holding unit 3 (mold 8). In order to cope with the high-precision positioning of the mold 8, the mold driving mechanism 22 may be formed of a plurality of driving systems including a coarse adjustment driving system, a fine adjustment driving system, and the like. The mold driving mechanism 22 can not only have a function of adjusting the Z-direction position of the mold 8 (the mold holding unit 3 holding the mold 8), but also have functions of adjusting the X-direction position, the Y-direction position, rotation and inclination around the Z axis, and the like. It should be noted that the operation of bringing the mold 8 into contact with the imprint material 19 on the substrate and the operation of separating the mold 8 from the cured imprint material 19 on the substrate can be achieved by driving the substrate stage 4 (substrate 11) in the Z direction. Alternatively, the operation of bringing the mold 8 into contact with the imprint material 19 on the substrate and the operation of separating the mold 8 from the cured imprint material 19 on the substrate can be achieved by driving both the mold holding unit 3 (mold 8) and the substrate stage 4.

[0037] The substrate 11 is a substrate onto which the pattern of the mold 8 is transferred. The imprint material 19 cured by the irradiation of the light 10 is disposed on the surface (processed surface) of the substrate 11. More specifically, the imprint material 19 is disposed in the imprint area on the surface of the substrate 11 for performing the imprint process.

[0038] The substrate stage 4 is a stage for holding the substrate 11. When bringing the mold 8 into contact with the imprint material 19 on the substrate, the substrate stage 4 is used to perform alignment between the substrate 11 and the mold 8. The substrate stage 4 includes a substrate holding unit 165 and an actuator (not shown), the substrate holding unit 165 attracting and holding the substrate 11 by an attractive force, and the actuator driving the substrate holding unit 165 (and the substrate 11 held thereby) in each axial direction. For example, a linear motor, a planar motor, etc. are applied to the actuator. The substrate stage 4 may be formed of a plurality of driving systems including a coarse adjustment driving system, a fine adjustment driving system, etc. for each of the X-axis direction and the Y-axis direction. The substrate stage 4 can not only have a function of adjusting the X-direction position and the Y-direction position of the substrate 11, but also have functions of adjusting the Z-direction position, rotation around the Z axis, rotation and inclination around the X axis and the Y axis, and the like.

[0039] In this embodiment, the dispenser 12 is provided near the mold holding unit 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 onto the substrate 11 is determined based on the target film thickness of the imprint material 19 to be disposed on the substrate, the density of the pattern of the imprint material 19 to be formed on the substrate, and the like.

[0040] The measuring unit 13 is used to perform alignment between the substrate 11 and the mold 8. More specifically, the measuring unit 13 is used to adjust the positional relationship (relative position) between the substrate 11 and the mold 8 so that the pattern formed on the substrate overlaps with the pattern of the mold 8 (the pattern to be formed). In this embodiment, the measuring unit 13 optically detects the overlapping pattern formed on the substrate and the overlapping pattern provided on the mold 8, and measures the positional deviation and shape deviation between these overlapping patterns.

[0041] The control unit 7 is formed of an information processing device (computer) including a CPU, a memory, etc. The control unit 7 operates the imprinting device 1 by uniformly controlling each unit of the imprinting device 1 according to the program stored in the storage unit. The control unit 7 may be formed integrally with the imprinting device 1 (in a common housing), or may also be formed separately from the imprinting device 1 (in another housing).

[0042] The imprinting process performed by the imprinting device 1 will be described here. The imprinting process is performed on each of the plurality of imprinting areas on the substrate by uniformly controlling each unit of the imprinting device 1 by the control unit 7.

[0043] First, the control unit 7 controls the substrate transfer mechanism 18 to transfer the substrate 11 to the substrate stage 4 (substrate holding unit 165), and causes the substrate stage 4 to hold the substrate 11. Then, in order to dispose the imprinting material 19 on the target imprinting area among the plurality of imprinting areas on the substrate, the control unit 7 drives the substrate stage 4 to position the target imprinting area below the dispenser 12. Then, the control unit 7 controls the dispenser 12 to dispose the imprinting material 19 on the target imprinting area on the substrate.

[0044] Then, the control unit 7 drives the substrate stage 4 to position the target imprinting area on the substrate where the imprinting material 19 is disposed below the mold 8 (its pattern area 9). Then, the control unit 7 drives the mold holding unit 3 via the mold driving mechanism 22 to bring the mold 8 into contact with the imprinting material 19 on the substrate (on the target imprinting area). Thereby, the imprinting material 19 is filled into the pattern formed in the pattern area 9 of the mold 8.

[0045] Then, in a state where the mold 8 is in contact with the imprinting material 19 on the substrate, the control unit 7 controls the irradiation unit 2 to irradiate the imprinting material 19 with light 10 via the mold 8. Thereby, the imprinting material 19 on the substrate is cured while being in contact with the mold 8.

[0046] Then, the control unit 7 drives the mold holding unit 3 via the mold driving mechanism 22 to separate the mold 8 from the cured imprinting material 19 on the substrate. Thereby, the pattern of the mold 8 is transferred to the imprinting material 19 on the substrate (on the target imprinting area).

[0047] By performing an imprinting process including the above-described series of processes on each of a plurality of imprinting regions on a substrate, a pattern of the imprinting material 19 (a pattern of a cured product on which the pattern of the mold 8 is transferred) is formed on each imprinting region.

[0048] A technique for overlapping the pattern formed on the substrate and the pattern of the mold 8 (pattern to be formed) will be described below.

[0049] First, as the mold 8 applied to the imprinting apparatus 1, the configuration of the mold 80 in the conventional technique will be referred to Figure 2 and described. As shown Figure 2 , the pattern region 90 of the pattern surface of the surface of the mold 80 facing the substrate 11 includes a main pattern region R1 and an overlapping pattern region R2. In the main pattern region R1, for example, a main pattern 15 such as a circuit pattern to be transferred onto the substrate 11 is formed. In the overlapping pattern region R2, an overlapping pattern 16 corresponding to the overlapping pattern formed on the substrate 11 and an overlapping pattern 31 different from the overlapping pattern 16 are formed. The overlapping pattern 16 is a pattern for aligning with the overlapping pattern formed on the substrate 11. The overlapping pattern 31 is a pattern for aligning with the substrate 11 when performing an imprinting process for forming the upper layer 30 as the second layer.

[0050] In the case of the mold 80 in the conventional technique ( Figure 2 ), the overlapping pattern on the substrate used (with respect to the overlapping pattern 16) when performing the imprinting process for forming the first layer becomes a pattern 25 that is cut and deformed by an etching process, as Figure 3A shown. Since the pattern 25 is deformed from the original shape of the overlapping pattern, the pattern 25 cannot be used for alignment between the mold 80 and the substrate 11. Therefore, in the case of performing an imprinting process for forming the upper layer 30 as the second layer, it is necessary to form an overlapping pattern 26 corresponding to the overlapping pattern 31 of the mold 80 on the substrate 11 instead of the pattern 25, as Figure 3B shown. Accordingly, the overlapping pattern region R2 of the pattern region 90 of the mold 80 (the region corresponding to the region where the overlapping pattern is formed on the substrate) increases, and the main pattern region R1 (the region corresponding to the region where the main pattern is formed on the substrate) decreases.

[0051] Therefore, this embodiment provides a technique for protecting overlapping patterns formed on a substrate during an etching process to eliminate the need to form overlapping pattern 26 on the substrate. More specifically, on the overlapping patterns formed on the substrate, a pattern of imprint material 19 that protects (covers) the overlapping patterns is formed. Thus, in this embodiment, when forming a pattern of imprint material 19 on each of a plurality of imprint regions on the substrate, an imprint process is performed such that the edges of the patterns of imprint material 19 formed on adjacent imprint regions slightly overlap each other. In other words, a pattern of imprint material 19 is formed on each of a first imprint region (first region) and a second imprint region (second region) on the substrate, and the second imprint region includes an overlapping region that overlaps the edge of the first imprint region.

[0052] <First Embodiment>

[0053] Reference Figures 4A to 4C , the structure of mold 50 in the first embodiment applied to mold 8 of imprint apparatus 1 and the structure of substrate 70 in the first embodiment applied as substrate 11 will be described.

[0054] As Figure 4A shown, a pattern region 51 that is to contact the imprint material 19 on the substrate is provided on the surface of mold 50 facing substrate 70. In this embodiment, pattern region 51 includes a main pattern region R3, an overlapping pattern region R4, and a protection pattern region R5. In main pattern region R1, for example, a main pattern 52 such as a circuit pattern that is to be transferred onto substrate 70 (the imprint material 19 on the substrate) is formed. In overlapping pattern region R4, an overlapping pattern 53 for aligning with the overlapping pattern 24 formed on the substrate is formed. In protection pattern region R5, a protection pattern 60 for forming a pattern of imprint material 19 on the overlapping pattern 24 formed on the substrate is formed.

[0055] As Figure 4B shown, 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. Overlapping pattern region R4 and protection pattern region R5 are provided in a region (peripheral region) around main pattern region R3. More specifically, protection pattern region R5 is provided in the peripheral region of main pattern region R3 along the first side SD1 and the second side SD2 that are in contact with each other among the four sides defining the outer peripheral shape (rectangular shape) of main pattern region R3. Overlapping pattern region R4 is provided in the peripheral region of main pattern region R3 along the third side SD3 and the fourth side SD4 that respectively face the first side SD1 and the second side SD2 among the four sides defining the outer peripheral shape (rectangular shape) of main pattern region R3. In this way, protection pattern region R5 is provided to face overlapping pattern region R4 with main pattern region R3 therebetween.

[0056] The overlapping pattern region R4 and the protection pattern region R5 have different structures. This is to ensure the overlap of the first pattern (its edge) and the second pattern (its edge) of the imprinted material 19 formed by imprinting processes on two adjacent imprint regions (the first region and the second region) on the substrate. For example, in the first pattern of the imprinted material 19 formed on the first imprint region on the substrate during the imprinting process, the pattern (the first part) in the region corresponding to the overlapping pattern region R4 is the pattern R4'. In the second pattern of the imprinted material 19 formed on the second imprint region adjacent to the first imprint region during the imprinting process, the pattern (the second pattern) in the region corresponding to the protection pattern region R5 is the pattern R5'. In this embodiment, the overlapping pattern region R4 and the protection pattern region R5 have different structures to ensure that the pattern R5' corresponding to the protection pattern region R5 overlaps with the pattern R4' corresponding to the overlapping pattern region R4.

[0057] In the protection pattern region R5, as Figure 4A shown by the slanted lines, the protection pattern 60 is formed as a recess formed by digging the surface facing the substrate 70 from the main pattern region R3, that is, a recess recessed from the main pattern region R3. In this embodiment, let h1 be the depth of the protection pattern 60 (the recess), h2 be the depth of the recessed part forming the main pattern 52, and h3 be the depth of the recessed part forming the overlapping pattern 53. Then each pattern is formed to satisfy h1≥h2 and h1>h3. In other words, the depth of the protection pattern 60 (the recess) is equal to or greater than the depth of the recessed part forming the main pattern 52 and greater than the depth of the recessed part forming the overlapping pattern 53.

[0058] Figure 4C The structure of the substrate 70 for the mold 50 is shown. As Figure 4C shown, in each of the multiple imprint regions on the substrate 70, the overlapping pattern 24 is formed at the position facing the overlapping pattern 53 of the mold 50 during the imprinting process on each imprint region.

[0059] The first pattern and the second pattern of the imprinted material 19 formed in the first imprint region and the second imprint region adjacent to each other on the substrate by using the mold 50 will be described. Here, the description will be made with particular attention to the pattern of the imprinted material 19 in the overlapping region of the edge of the first imprint region and the edge of the second imprint region.

[0060] Figure 5It is a view showing a first pattern 100 of an imprint material 19 formed on a first imprint area formed on a substrate, and a second pattern 101 of the imprint material 19 formed on a second imprint area adjacent to the first imprint area. The first pattern 100 and the second pattern 101 are formed on corresponding imprint areas on the substrate by an imprint process using a mold 50. Figure 5 It shows an overlapping area R6 which is an area where the edge of the first imprint area and the edge of the second imprint area overlap. An overlapping pattern 24 is formed in the overlapping area R6.

[0061] Reference Figure 5 , a first part 111 of the first pattern 100 and a second part 110 of the second pattern 101 overlap in the overlapping area R6. It should be noted that the first part 111 corresponds to a pattern R4' in an area of the first pattern 100 corresponding to the overlapping pattern area R4. The second part 110 corresponds to a pattern R5' in an area of the second pattern 101 corresponding to the protection pattern area R5. In this way, in the imprint process on the second imprint area, the protection pattern 60 of the mold 50 forms a second part 110 of the second pattern 101 covering the first part 111 of the first pattern 100 on the overlapping pattern 24 formed in the overlapping area R6. In other words, the main pattern of the first pattern 100 is formed in the central area of the first imprint area, and the second part 110 of the second pattern 101 is formed in a peripheral area (overlapping area R6) around the central area of the first imprint area.

[0062] The main pattern of the first pattern 101 corresponding to the main pattern 52 of the mold 50 is formed in the central area of the first imprint area. In this case, it can also be said that the second part 110 of the second pattern 101 is formed in a peripheral area (overlapping area R6 which is the edge of the first imprint area and the second imprint area) around the central area of the first imprint area.

[0063] Here, let h5 be the residual film thickness of the first pattern 100 and the second pattern 101 formed by the imprint process. In addition, let h1' be the height of the second part 110 (pattern R5') of the second pattern 101, and h2' be the height of the main pattern 112 of the second pattern 101 corresponding to the main pattern 52 of the mold 50. In addition, let h3' be the height of the first part 111 (pattern R4') of the first pattern 100, more specifically, the height of the pattern of the first pattern 100 corresponding to the overlapping pattern 53 of the mold 50.

[0064] In this embodiment, the sum of the height h1' of the second portion 110 and the residual film thickness h5 is set to be greater than the sum of the height h3' of the first portion 111 and the residual film thickness h5. In other words, the height h1' of the second portion 110 is greater than the height h3' of the first portion 111. This can prevent the mold 50 from contacting and damaging the first portion 111 of the first pattern 100 formed on the first imprint area during the imprinting process on the second imprint area adjacent to the first imprint area.

[0065] In addition, in this embodiment, the sum of the height h1' of the second portion 110 and the residual film thickness h5 is set to be equal to or greater than the sum of the height h2' of the main pattern 112 of the second pattern 101 and the residual film thickness h5. In other words, in the second pattern 101, the height of the second portion 110 is equal to or greater than the height of the main pattern 112. In this way, in this 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 area R6 becomes greater than the total film thickness of the main pattern 112 of the second pattern 101. When transferring the main pattern 112 of the second pattern 101 onto the substrate 70, this can prevent the overlapping pattern 24 formed on the substrate 70 from being cut and deformed by the etching process.

[0066] As described above, in this embodiment, the overlapping pattern 24 formed on the substrate can be protected, and when performing the imprinting process for forming the upper layer on the first pattern 100 and the second pattern 101, the overlapping pattern 24 can be reused. Therefore, it is not necessary to form an overlapping pattern 26 different from the overlapping pattern 24 on the substrate and it is not necessary to form an overlapping pattern 31 corresponding to the overlapping pattern 26 on the mold 80. Therefore, the main pattern area R3 of the mold 80 can be increased.

[0067] In this embodiment, it has been described that the sum of the height h1' of the second portion 110 of the second pattern 101 and the residual film thickness h5 is set to be equal to or greater than the sum of the height h2' of the main pattern 112 of the second pattern 101 and the residual film thickness h5. However, in practice, 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.

[0068] Reference Figure 6 and Figure 7, the sequence of the imprinting process in the first embodiment will be described below. In this embodiment, when forming a pattern of the imprinting material 19 on each of the plurality of imprinting regions on the substrate, the imprinting process is performed such that the edges of the patterns of the imprinting material 19 formed on adjacent imprinting regions slightly overlap each other. More specifically, as described above, by using the imprinting apparatus 1 to which the mold 50 is applied, the imprinting process is performed on all the imprinting regions on the substrate such that the second portion 110 of the second pattern 101 is formed on the first portion 111 of the first pattern 100. In this embodiment, for example, the imprinting process is performed on the plurality of imprinting regions on the substrate in the order as shown in Figure 6 The imprinting process is performed on the plurality of imprinting regions on the substrate in the order shown.

[0069] Figure 7 is a flowchart for describing the imprinting process in the first embodiment. As described above, the imprinting process is performed by the unified control of each unit of the imprinting apparatus 1 by the control unit 7.

[0070] In step S100, the dispenser 12 disposes the imprinting material 19 on the first imprinting region, which is one of the plurality of imprinting regions on the substrate, as the target of the imprinting process.

[0071] In step S101, the mold 50 (its pattern region 51) is brought into contact with the imprinting material 19 disposed on the first imprinting region. More specifically, the substrate stage 4 is driven to position the first imprinting region on which the imprinting material 19 is disposed below the mold 50, and the mold driving mechanism 22 brings the mold 50 into contact with the imprinting material 19 on the first imprinting region. Thus, the imprinting material 19 is filled into the pattern formed in the pattern region 51 of the mold 50.

[0072] In step S102, alignment between the substrate 70 and the mold 50 is performed. More specifically, the measuring unit 13 measures the relative position between the overlapping pattern 24 (the overlapping region R6 between the first target region and the second target region) formed on the substrate 70 and the overlapping pattern 53 provided on the mold 50. Based on the relative position measured by the measuring unit 13, the substrate stage 4 is driven to align the first imprinting region of the substrate 70 and the pattern region 51 of the mold 50. Thus, step S102 is also a step of aligning the substrate 70 to adjust the position where the first pattern 100 is formed in the first imprinting region (the first alignment step).

[0073] In step S103, with the mold 50 in contact with the imprinting material 19 disposed on the first imprinting region, the imprinting material 19 is cured. More specifically, the irradiation unit 2 irradiates the imprinting material 19 with light through the mold 50, thereby curing the imprinting material 19 disposed on the first imprinting region.

[0074] In step S104, mold separation is performed. More specifically, the mold driving mechanism 22 separates the mold 50 from the cured imprinting material 19 on the first imprinting area.

[0075] In step S105, the dispenser 12 disposes the imprinting material 19 on a second imprinting area that is an imprinting process target adjacent to the first imprinting area among a plurality of imprinting areas on the substrate 70.

[0076] In step S106, the mold 50 (its pattern area 51) is brought into contact with the imprinting material 19 disposed on the second imprinting area. More specifically, the substrate stage 4 is driven to position the second imprinting area on which the imprinting material 19 is disposed below the mold 50, and the mold driving mechanism 22 brings the mold 50 into contact with the imprinting material 19 on the second imprinting area. Accordingly, the imprinting material 19 is filled in the pattern formed in the pattern area 51 of the mold 50.

[0077] In step S107, alignment between the substrate 70 and the mold 50 is performed. More specifically, the measuring unit 13 measures the relative position between the overlapping pattern 24 (the overlapping area between the second target area and the third target area adjacent to the second target area) formed on the substrate 70 and the overlapping pattern 53 provided on the mold 50. Based on the relative position measured by the measuring unit 13, the substrate stage 4 is driven to align the second imprinting area of the substrate 70 and the pattern area 51 of the mold 50. Thereby, the overlapping pattern 24 formed in the overlapping area R6 overlaps with the protection pattern 60 of the mold 50. Accordingly, step S107 is also a step of aligning the substrate 70 to adjust the position where the second pattern 101 is formed in the second imprinting area (second alignment step).

[0078] In step S108, with the mold 50 in contact with the imprinting material 19 disposed on the second imprinting area, the imprinting material 19 is cured. More specifically, the irradiation unit 2 irradiates the imprinting material 19 with light through the mold 50, thereby curing the imprinting material 19 disposed on the second imprinting area.

[0079] In step S109, mold separation is performed. More specifically, the mold driving mechanism 22 separates the mold 50 from the cured imprinting material 19 on the second imprinting area.

[0080] In this way, the first pattern 100 and the second pattern 101 of the imprint material 19 are respectively formed in the first imprint area and the second imprint area of the substrate 70. By repeating steps S105 to S109, the imprint process is performed on all the imprint areas of the substrate 70. Thus, the pattern (the second part 110 of the second pattern 101) of the imprint material 19 for protecting the overlapping pattern 24 can be formed on the overlapping pattern 24 formed in each imprint area of the substrate 70. Therefore, the overlapping pattern 24 formed on the substrate 70 can be prevented from being cut and deformed by the etching process, so that the overlapping pattern 24 can be reused when forming the upper layer. This helps to reduce the area where the overlapping pattern 24 is formed on the substrate 70.

[0081] <Second Embodiment>

[0082] In the first embodiment, the overlapping pattern 53 is provided in the peripheral area of two sides that are in contact with each other among the four sides along the rectangular outer peripheral shape defining the main pattern area R3 of the mold 80 in order to perform alignment with the substrate 70. However, if the overlapping pattern 53 is provided in the peripheral area that entirely surrounds the main pattern area R3 of the mold 50, the overlapping accuracy can be improved, and alignment can be performed even when the imprint area on the outer periphery of the substrate 70 is narrow. Therefore, the second embodiment provides a technique that can protect the overlapping pattern on the substrate and can provide an overlapping pattern that entirely surrounds the imprint area.

[0083] Reference Figure 8A and Figure 8B will describe the structure of the mold 150 in the second embodiment applied to the mold 8 of the imprint apparatus 1, and the structure of the substrate 211 in the second embodiment applied as the substrate 11. Note that the structure of the mold 150 not described in this embodiment is similar to the structure of the mold 50.

[0084] As Figure 8A shown, in this embodiment, the pattern area 51 provided on the surface of the mold 150 facing the substrate 211 includes a main pattern area R3, an overlapping pattern area R4, a protection pattern area R5, and an overlapping pattern area R7. In the overlapping pattern area R7, an overlapping pattern 154 for aligning with the overlapping pattern 24 formed on the substrate is formed. The overlapping pattern area R7 is provided in the peripheral area between the main pattern area R3 and the protection pattern area 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 area R3. Therefore, the overlapping pattern 53 and the overlapping pattern 154 are formed in the peripheral area that entirely surrounds the main pattern area R3 of the mold 150.

[0085] In this embodiment, the recess for forming the protection pattern 60 extends to the overlapping pattern area R7, as Figure 8AAs shown. In other words, the overlapping pattern region R7 is formed by a recess formed by digging into the surface facing the substrate 211 from the main pattern region R3, and the overlapping pattern 154 is formed by a recessed portion formed in the recess. Therefore, the depth h4 of the overlapping pattern region R7 (recess) is greater than the depth h2 of the recessed portion forming the main pattern 52.

[0086] In this way, in this embodiment, the mold 150 has such a structure that the overlapping pattern region R7 is provided outside the main pattern region R3, and the protective pattern region R5 (protective pattern 60) is provided even further outside. Thus, as Figure 8B shown, alignment of the overall surrounding imprint area can be performed by using the substrate 211 provided with the overlapping pattern 24 that overall surrounds each imprint area.

[0087] Figure 9 is a view showing the first pattern 100 of the imprint material 19 formed on the first imprint area formed on the substrate, and the second pattern 101 of the imprint material 19 formed on the second imprint area adjacent to the first imprint area. The first pattern 100 and the second pattern 101 are formed in the corresponding imprint areas on the substrate by an imprint process using the mold 150. Similarly to the first embodiment, the overlapping pattern 24 formed in the overlapping area R6 between the first imprint area and the second imprint area is protected by the first part 111 of the first pattern 100 and the second part 110 of the second pattern 101.

[0088] In this embodiment, in the second pattern 101 of the imprint material 19 formed by an imprint process on the second imprint area on the substrate, the pattern in the area corresponding to the overlapping pattern region R7 is the third part 113. In the overlapping pattern region R7, the sum of the height h4' of the third part 113 of the second pattern 101 and the residual film thickness h5 is set to be equal to or greater than the sum of the height h2' of the main pattern 112 of the second pattern 101 and the residual film thickness h5. In other words, in the second pattern 101, the height of the third part 113 is equal to or greater than the height of the main pattern 112. In this way, in this embodiment, the second pattern 101 is formed such that the total film thickness of the pattern (third part 113) of the imprint material 19 formed on the overlapping pattern region R7 is greater than the total film thickness of the main pattern 112 of the second pattern 101. When transferring the main pattern 112 of the second pattern 101 onto the substrate 211, this can suppress the overlapping pattern 24 formed on the substrate 211 from being cut and deformed by an etching process.

[0089] The sequence of the imprinting process in the second embodiment is substantially similar to the sequence of the imprinting process in the first embodiment, but the difference lies in the alignment between the substrate 211 and the mold 150 in step S107. In this embodiment, in step S107, the alignment between the substrate 211 and the mold 150 is performed using not only the overlapping pattern 24 formed in the overlapping pattern region R4 but also the overlapping pattern 24 formed in the overlapping pattern region R7. Therefore, in this embodiment, compared with the first embodiment, the alignment accuracy between the substrate 211 and the mold 150 can be improved, that is, the overlapping accuracy between the pattern already formed on the substrate and the pattern to be formed can be improved.

[0090] <Third Embodiment>

[0091] In the second embodiment, in order to implement the die-by-die alignment method, it is necessary to form the overlapping pattern 24 for each imprinting area on the substrate. In the third embodiment, the area (total area) of the overlapping pattern 24 formed on the substrate is reduced by sharing the overlapping pattern 24 among adjacent imprinting areas on the substrate.

[0092] Reference Figure 10A and Figure 10B will describe the structure of the mold 250 in the third embodiment applied to the mold 8 of the imprinting device 1 and the structure of the substrate 311 in the third embodiment applied as the substrate 11. Note that the structure of the mold 250 not described in this embodiment is similar to the structure of the mold 50.

[0093] As Figure 10A shown, in this embodiment, the pattern area 51 provided on the surface of the mold 250 facing the substrate 311 includes a main pattern area R3, an overlapping pattern area R4, and a protection pattern area R5. In this embodiment, in the protection pattern area R5, in addition to the protection pattern 60, an overlapping pattern 254 for alignment with the overlapping pattern 24 formed on the substrate is also formed. The overlapping pattern 254 is formed by the recessed portion formed in the recess of the protection pattern 60 directly above the protection pattern 60.

[0094] In this embodiment, as Figure 10B shown, when aligning between the substrate 311 and the mold 250, the overlapping pattern 24 formed in the outer periphery of each imprinting area on the substrate 311 is shared by adjacent imprinting areas. Thus, compared with the second embodiment, the area of the overlapping pattern 24 formed on the substrate 311 can be reduced, and the area for forming the main pattern can be increased.

[0095] Figure 11It is a view showing a first pattern 100 of an imprint material 19 formed on a first imprint area formed on a substrate, and a second pattern 101 of the imprint material 19 formed on a second imprint area adjacent to the first imprint area. The first pattern 100 is aligned with an overlapping pattern 24 formed on the substrate 311, and a first portion 111 for alignment is formed on the overlapping pattern 24.

[0096] When an imprint process is performed on a second imprint area adjacent to the first imprint area using a 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 area and the imprint material 19 disposed in the second imprint area are formed of the same material and have the same refractive index, the measuring unit 13 cannot optically detect the boundary therebetween. Thus, in the overlapping area R6, the measuring unit 13 can measure the relative position between the overlapping pattern 24 on the substrate and the overlapping pattern 254 of the mold 250 without being obstructed by the first portion 111 of the first pattern 100.

[0097] The sequence of the imprint process in the third embodiment is substantially similar to the sequence of the imprint process in the first embodiment, but the difference lies in the alignment between the substrate 311 and the mold 250 in step S107. In step S107, the measuring unit 13 measures the relative position between the overlapping pattern 24 formed on the substrate 311 and the overlapping patterns 53 and 254 provided on the mold 250. Based on the relative position between the overlapping pattern 24 and the overlapping patterns 53 and 254 measured by the measuring unit 13, the substrate stage 4 is driven to align the second imprint area on the substrate 70 and the pattern area 51 of the mold 50. As described above, through steps S100 to S104, the first portion 111 of the first pattern 100 is formed on the overlapping pattern 24 in the overlapping area R6 formed on the substrate 311. However, in step S105, the imprint material 19 is filled between the first portion 111 of the first pattern 100 and the pattern area 51 of the mold 250, more specifically, between the first portion 111 and the protection pattern area R5. Thereby, the relative position between the overlapping pattern 24 and the overlapping pattern 254 can be measured without being obstructed by the first portion 111 in the overlapping area R6. In other words, in step S102 (the first alignment step) and step S107 (the second alignment step), the same overlapping pattern 24 formed on the substrate 311 can be used to align the substrate 311.

[0098] The pattern of the cured product formed by the imprinting device 1 in this embodiment is permanently used for at least some of various articles or temporarily used in manufacturing various articles. The articles are circuit elements, optical elements, MEMS, recording elements, sensors, molds, etc. Examples of circuit elements are volatile and 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 molds are molds for imprinting.

[0099] The pattern of the cured product is directly used as a constituent member of at least some of the above articles or temporarily used as a resist mask. After performing etching or ion implantation in the substrate processing step, the resist mask is removed.

[0100] Next, a detailed description of the method for manufacturing an article is given. As Figure 12A shown, a substrate (e.g., a silicon wafer) having a material to be processed (e.g., an insulator) formed on its surface is prepared. Next, an imprinting material is applied to the surface of the material to be processed by an inkjet method or the like. The state of applying the imprinting material as a plurality of droplets to the substrate is shown here.

[0101] As Figure 12B shown, the side of the mold for imprinting having a protrusion and groove pattern is formed to face the imprinting material on the substrate. As Figure 12C shown, the substrate to which the imprinting material is applied is brought into contact with the mold, and pressure is applied. The imprinting material is filled in the gap between the mold and the material to be processed. In this state, when the imprinting material is irradiated with light used as curing energy through the mold, the imprinting material is cured.

[0102] As Figure 12D shown, after the imprinting material is cured, the mold is released from the substrate. Thus, a pattern of the cured product of the imprinting material is formed on the substrate. In the pattern of the cured product, the grooves of the mold correspond to the protrusions of the cured product, and the protrusions of the mold correspond to the grooves of the cured product. That is, the protrusion and groove pattern of the mold is transferred to the imprinting material.

[0103] As Figure 12E shown, when performing etching using the pattern of the cured product as an anti-etching mask, the portions of the surface of the material to be processed where there is no cured product or where a relatively thin layer remains are removed to form grooves. As Figure 12F shown, when the pattern of the cured product is removed, an article having grooves formed in the surface of the material to be processed can be obtained. Here, the pattern of the cured material is removed, but for example, the pattern can be not removed after processing but used as a film for insulation between layers included in a semiconductor element or the like, in other words, used as a constituent member of the article.

[0104] Although the present invention has been described with reference to exemplary embodiments, it should be understood that the present invention is not limited to the disclosed exemplary embodiments. The scope of the appended claims should be accorded the broadest interpretation so as to cover all such modifications as well as equivalent structures and functions.

Claims

1. An imprinting method for forming a pattern in an imprinting material on each of a first region and a second region disposed on a substrate, the second region including an overlapping region overlapping with an edge of the first region, the imprinting method comprising: forming a first pattern in the imprinting material on the first region, the first pattern including a main pattern and a first portion formed on an overlapping pattern formed in the overlapping region, and forming a second pattern in the imprinting material on the second region, the second pattern including a main pattern and a second portion covering the first portion of the first pattern, wherein when forming the second pattern, the second pattern is formed such that a film thickness of a pattern formed in the overlapping region is greater than a film thickness of the main pattern of the second pattern.

2. The imprinting method according to claim 1, wherein a height of the second portion of the second pattern is not less than a height of the main pattern of the second pattern.

3. The imprinting method according to claim 1, wherein a height of the second portion of the second pattern is greater than a height of the first portion of the first pattern.

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

5. The imprinting method according to claim 1, wherein forming the first pattern includes aligning the substrate to adjust a position of forming the first pattern in the first region, forming the second pattern includes aligning the substrate to adjust a position of forming the second pattern in the second region, and when aligning the substrate to adjust the position of forming the first pattern in the first region and aligning the substrate to adjust the position of forming the second pattern in the second region, the same overlapping pattern formed on the substrate is used to align the substrate.

6. A mold for forming a pattern in an imprinting material on a substrate, the mold comprising: a substrate; and a pattern region provided on a surface of the substrate facing the substrate and in contact with the imprinting material, wherein the pattern region includes: a main pattern region in which a main pattern to be transferred to the imprinting material is formed; and a protection pattern region provided around the main pattern region and formed with a protection pattern for forming a pattern in the imprinting material on an overlapping pattern formed on the substrate, and the protection pattern includes a recess recessed from the main pattern region.

7. The mold according to claim 6, wherein a depth of the recess is not less than a depth of a recessed portion forming the main pattern.

8. The mold according to claim 6, wherein the main pattern region has a rectangular outer peripheral shape, and the protection pattern region is provided in a region around the main pattern region along a first side and a second side that are in contact with each other among four sides defining the rectangle.

9. The mold according to claim 8, wherein The pattern region further includes an overlapping pattern region, in which an overlapping pattern is formed for aligning with the overlapping pattern formed on the substrate, and the overlapping pattern region is disposed in a region around the main pattern region and is disposed along the third side and the fourth side of the four sides that are respectively opposite to the first side and the second side.

10. The mold according to claim 6, wherein the pattern region further includes an overlapping pattern region, in which an overlapping pattern is formed for aligning with the overlapping pattern formed on the substrate, and the overlapping pattern region is disposed in a region between the main pattern region and the protection pattern region.

11. The mold according to claim 10, wherein the recess for forming the protection pattern extends into the overlapping pattern region, and the overlapping pattern formed in the overlapping pattern region is formed by a recessed portion formed in the recess.

12. The mold according to claim 6, wherein an overlapping pattern for aligning with the overlapping pattern formed on the substrate is further formed in the protection pattern region, and the overlapping pattern formed in the protection pattern region is formed by a recessed portion formed in the recess.

13. An imprinting apparatus for forming a pattern in an imprint material on a substrate by using a mold, the imprinting apparatus including: a mold holding unit configured to hold the mold; and a substrate holding unit configured to hold the substrate, wherein the mold includes the mold according to claim 6.

14. An article manufacturing method, the article manufacturing method including: a forming step of forming a pattern on a substrate by using the imprinting method according to claim 1; processing the substrate on which the pattern is formed in the forming step; and manufacturing an article from the processed substrate.

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