Imprinting apparatus and method for manufacturing an article

Abstract

To provide an imprint device capable of effectively reducing a relative inclination between a mold and a substrate when forming a pattern of an imprint material.SOLUTION: An imprint device comprises a control unit for executing: a contact step of moving at least one of a mold holding unit and a substrate holding unit by at least one of a mold driving unit and a substrate driving unit in such a manner that a mold and an imprint material on a substrate surface are brought into contact with each other; an acquisition step of acquiring drive power due to the substrate driving unit in a first direction in parallel with the substrate surface with respect to the substrate holding unit after the contact step is executed; and an inclination correction step of rotating the mold holding unit around a second direction which is vertical to the first direction, within the substrate surface based on a magnitude of the drive power acquired in the acquisition step.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an imprint apparatus. [Background technology]

[0002] Conventionally, in an imprint apparatus, it is required to improve the overlay accuracy by reducing distortion caused by the relative tilt between the mold and the substrate when forming a pattern of an imprint material. Patent document 1 discloses an imprinting device that changes the inclination of a mold based on the contact position of the mold in the surface direction of the substrate in order to reduce the relative inclination between the mold and the substrate caused by the tilt of the substrate holding part that holds the substrate when the mold and the imprinting material on the substrate are brought into contact with each other. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-157639 Summary of the Invention [Problem to be solved by the invention]

[0004] As described above, the method disclosed in Patent Document 1 is effective in reducing the relative tilt between the mold and the substrate that accompanies the tilt of the substrate holder. However, in an imprinting device, it is known that the relative tilt between the mold and the substrate can change not only due to the above but also due to factors such as the thickness of the imprinting material on the substrate and the pressing force of the mold when it is brought into contact with the imprinting material on the substrate. SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an imprint apparatus that can effectively reduce the relative tilt between a mold and a substrate when forming a pattern of an imprint material. [Means for solving the problem]

[0005] The imprinting apparatus according to the present invention is on the board Imprint material to An imprinting apparatus for forming a pattern includes a mold holding unit for holding a mold, a mold driving unit for moving the mold holding unit, a substrate holding unit for holding a substrate, a substrate driving unit for moving the substrate holding unit, and a control unit for controlling the mold driving unit and the substrate driving unit, and the control unit controls the mold and the substrate. on the board Imprint material and is connected At least one of the mold driving unit and the substrate driving unit is Control A contact step in which the , basis In a first direction parallel to the plate surface Board drive unit Driving force Information and a driving force acquisition step of acquiring the driving force acquired in the acquisition step. information Based on the type drive unit Reduces the relative tilt between the mold and the substrate and a tilt correction step of correcting the tilt of the image. [Effects of the Invention]

[0006] According to the present invention, it is possible to provide an imprint apparatus that can effectively reduce the relative tilt between a mold and a substrate when forming a pattern of an imprint material. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic cross-sectional view of an imprint apparatus according to a first embodiment. [Figure 2] FIG. 2 is a partially enlarged cross-sectional view of the imprint apparatus according to the first embodiment when the mold and the substrate are in contact with each other. [Figure 3] 4 is a flowchart showing an imprint process in the imprint apparatus according to the first embodiment. [Figure 4] 5A to 5C are diagrams showing examples of the time dependence of the driving force of an actuator and the tilt fluctuation amount of a mold holding part in some steps of an imprint process performed by the imprint apparatus according to the first embodiment. [Figure 5] 10 is a flowchart showing an imprint process in an imprint apparatus according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] The imprint apparatus according to this embodiment will be described in detail below with reference to the accompanying drawings. Note that the drawings may be drawn at a scale different from the actual scale in order to facilitate understanding of this embodiment.

[0009] [First embodiment] In response to recent demands for further miniaturization in semiconductor devices, MEMS, etc., imprint technology, which can form fine patterns (structures) on the order of a few nanometers on a substrate, is attracting attention in addition to conventional photolithography technology. Specifically, imprinting technology is a microfabrication technology in which uncured imprinting material is supplied (applied) onto a substrate, and then the imprinting material is brought into contact with a mold and cured, thereby forming a pattern of the imprinting material on the substrate that corresponds to the fine uneven pattern formed on the mold.

[0010] One method for curing the imprint material in the imprint technology is a photo-curing method. The photocuring method is a method of forming a pattern of imprint material on a substrate by bringing the imprint material supplied to a shot area on the substrate into contact with the pattern area of ​​a mold and then curing the imprint material by irradiating it with, for example, ultraviolet light.

[0011] Another known method is to suppress the remaining air bubbles in the pattern area of ​​the mold by deforming the pattern area of ​​the mold into a convex shape that protrudes toward the substrate, and then bringing the mold and the imprint material on the substrate into contact with each other.

[0012] Generally, when the mold and the imprint material on the substrate are brought into contact with each other, at least one of the mold and the substrate is controlled so that the relative inclination between the mold and the substrate is zero, i.e., so that the surface on which the mold pattern is formed and the substrate surface are parallel to each other. However, when the mold and substrate are brought into contact with each other while the pattern area of ​​the mold is deformed into a convex shape as described above, it becomes difficult to reduce the relative tilt between the mold and substrate to zero due to the influence of imprint conditions including warpage of the substrate, deformation according to the rigidity of the substrate holder, and shot position.

[0013] Therefore, a technique has been proposed for reducing the moment that changes the relative tilt between the mold and the substrate, which is generated when the mold and the imprint material on the substrate are brought into contact with each other. Specifically, this technique performs an imprint process on a test substrate in advance, and determines the moment during each period, such as an imprinting period in which the mold is brought into contact with the imprint material on the substrate, a filling period in which the imprint material is filled into the pattern area of ​​the mold, etc. Also, a target value for the relative tilt that keeps the moment within an allowable range is determined. Then, in subsequent imprint processing of the substrate, the relative inclination between the mold and the substrate is set to the determined target value, and then the moment can be reduced by bringing the mold and the imprint material on the substrate into contact with each other.

[0014] Although the technique of performing correction using the results obtained by performing imprint processing in advance, as in the above technique, is useful, it is not very robust because the exact cause of the moment has not been identified in the first place. In other words, if an imprint process is performed under imprint conditions that are even slightly different from the imprint conditions of a previously performed imprint process, the difference will affect the relative tilt between the mold and the substrate, making it difficult to reduce the moment.

[0015] As a result of extensive research, the inventors of the present invention have noticed that one of the factors that generates the moment is the movement of the substrate holder after the mold and the substrate are brought into contact with each other. Therefore, the present embodiment aims to provide an imprint apparatus that can effectively reduce the relative tilt between the mold and the substrate based on the driving force applied to the substrate stage during the movement of the substrate holding part.

[0016] FIG. 1 shows a schematic cross-sectional view of an imprint apparatus 1 according to the first embodiment.

[0017] The imprinting apparatus 1 of this embodiment is used to manufacture devices such as semiconductor devices as articles, and specifically is a lithography apparatus that performs an imprinting process in which a pattern of imprinting material 30 is formed on a substrate 29 using a mold 19. Specifically, in the imprinting apparatus 1 according to this embodiment, the imprinting material 30 supplied onto the substrate 29 is brought into contact with the mold 19, and then energy for curing is applied to the imprinting material 30. This allows a pattern of the cured material to which the concave-convex pattern of the mold 19 has been transferred to be formed.

[0018] As shown in Figure 1, the imprint apparatus 1 according to this embodiment includes an illumination unit 2, a mold holding mechanism 3, a substrate stage 4, a supply unit 5, a mold control unit 7 (control unit), an alignment measurement unit 8 (position measurement unit), and a substrate control unit 10 (control unit).

[0019] The imprint material 30 used in the imprint apparatus 1 according to this embodiment is a curable composition (also called uncured resin) that is cured when curing energy is applied. The energy used for curing may be electromagnetic waves, heat, etc. The electromagnetic waves may be, for example, infrared rays, visible light, ultraviolet light, or other light having a wavelength selected from the range of 10 nm to 1 mm.

[0020] That is, a curable composition is a composition that is cured by irradiation with light or by heating. In particular, a photocurable composition that is cured by irradiation with light contains at least a polymerizable compound and a photopolymerization initiator, and may contain a non-polymerizable compound and a solvent as necessary. The non-polymerizable compound referred to here is at least one selected from the group consisting of sensitizers, hydrogen donors, internal mold release agents, surfactants, antioxidants, and polymer components.

[0021] In the imprint apparatus 1 according to this embodiment, the imprint material 30 may be applied in the form of a film onto the substrate 29 by a spin coater or a slit coater that constitutes the supply unit 5. Alternatively, the imprint material 30 may be applied onto the substrate 29 by a liquid ejecting head constituting the supply unit 5 in the form of droplets, islands formed by connecting a plurality of droplets, or a film. The viscosity (at 25° C.) of the imprint material 30 used in the imprint apparatus 1 according to this embodiment is, for example, not less than 1 mPa·s and not more than 100 mPa·s.

[0022] Furthermore, in the imprinting apparatus 1 according to this embodiment, glass, ceramics, metal, semiconductor, resin, etc. are used as the material for the substrate 29, and if necessary, a member made of a material different from the substrate 29 may be formed on the surface of the substrate 29. Specifically, the substrate 29 used in the imprint apparatus 1 according to this embodiment includes a silicon wafer, a compound semiconductor wafer, and quartz glass.

[0023] The imprint apparatus 1 according to this embodiment employs a photo-curing method as a method for curing the imprint material 30. The direction parallel to the optical axis of the illumination unit 2 that irradiates the curing light 12 onto the imprint material 30 on the substrate 29 (the direction perpendicular to the substrate surface) is the Z axis, and the two directions that are perpendicular to each other in a plane perpendicular to the Z axis (within the substrate surface) are the X axis and Y axis (first direction and second direction).

[0024] As shown in Figure 1, the mold holding mechanism 3 is composed of a mold holding unit 20 that holds the mold 19, a mold base that holds the mold holding unit 20, and a mold driving unit 31 that moves the mold holding unit 20 relative to the mold base.

[0025] The mold holding unit 20 attracts and holds the mold 19 by attracting the outer peripheral area of ​​the surface of the mold 19 on which the curing light 12 is incident by vacuum suction or electrostatic force. For example, when the mold holding unit 20 holds the mold 19 by vacuum suction force, the mold holding unit 20 is connected to an external vacuum pump (not shown), and the mold 19 can be attached and detached (held and released) by turning the vacuum pump on and off.

[0026] The mold driving unit 31 moves the mold holding unit 20 that holds the mold 19 in the Z direction so as to selectively press the mold 19 against the imprint material 30 on the substrate 29 (imprinting process) and release the mold 19 from the imprint material 30 on the substrate 29 (mold release process). Actuators that can be used as the mold driving unit 31 include, for example, linear motors and air cylinders.

[0027] The mold driving unit 31 may be made up of a plurality of driving systems including a coarse movement driving system and a fine movement driving system in order to position the mold 19 with high precision. Furthermore, the mold driving unit 31 is configured to be able to move the mold 19 in the X and Y directions in addition to the Z direction. Furthermore, the die driving unit 31 drives the die 19 in the θ Z θ corresponds to the position and tilt in the direction (rotation direction around the Z axis) X Direction and θ Y It is configured to have a tilt function for adjusting the position in the directions (rotational directions around the X axis and rotational directions around the Y axis).

[0028] In addition, the imprinting process and the release process in the imprinting apparatus 1 according to this embodiment are performed by moving the mold 19 in the Z-axis direction, but this is not limited to this and may also be performed by moving the substrate 29 (i.e., the substrate stage 4) in the Z-axis direction. Furthermore, the imprinting process and the mold release process may be performed by moving both the mold 19 and the substrate 29 relatively in the Z-axis direction.

[0029] Each of the mold holding section 20, mold base and mold driving section 31 that constitute the mold holding mechanism 3 has an opening formed inside, including the center, so that the curing light 12 from the lighting section 2 can be irradiated onto the imprint material 30 on the substrate 29. A light-transmitting member is placed in the opening to seal the space surrounded by a part of the opening and the mold 19, and the pressure within the sealed space is adjusted by a pressure adjustment device (not shown) including a vacuum pump or the like.

[0030] For example, when the imprint material 30 on the substrate 29 and the mold 19 are brought into contact with each other, the pressure adjustment device can make the pressure inside the sealed space higher than the external pressure, thereby causing the pattern area 19a of the mold 19 to bend (deform) into a convex shape toward the substrate 29. Therefore, the imprint material 30 on the substrate 29 can be brought into contact with the center of the pattern region 19 a of the mold 19 .

[0031] This makes it possible to prevent air from remaining between the pattern region 19a of the mold 19 and the imprint material 30 during this contact, and allows the imprint material 30 to fill every corner of the pattern region 19a of the mold 19. In the imprint apparatus 1 according to this embodiment, the pattern of the mold 19 can be formed in the imprint material 30 on the substrate 29 as described above.

[0032] The substrate stage 4 moves while holding the substrate 29, thereby enabling alignment of the substrate 29 with respect to the mold 19 when forming a pattern of the imprint material 30 on the substrate 29. As shown in FIG. 1, the substrate stage 4 includes a Y stage 23 (substrate holding part) that holds the substrate 29 by suction and is movable at least in the Y direction, and an X stage 24 (substrate holding part) that mechanically holds the Y stage 23 and is movable at least in the X direction. The substrate stage 4 also includes an encoder system 25, a Y actuator 41 (substrate driving section), and an X actuator 42 (substrate driving section).

[0033] The Y stage 23 can be moved by driving a Y actuator 41 consisting of a Y movable part 41a and a Y fixed part 41b, and the X stage 24 can be moved by driving an X actuator 42 consisting of an X movable part 42a and an X fixed part 42b. As the Y actuator 41 and the X actuator 42, for example, a linear motor or a planar motor can be used. Each of the Y stage 23 and the X stage 24 may be made up of a plurality of stages including a coarse movement stage and a fine movement stage in order to position the substrate 29 with high precision.

[0034] The X stage 24 may also be configured to be able to move the substrate 29 in the Z direction. Furthermore, the X stage 24 rotates in the θ direction of the substrate 29. Z θ corresponds to the position and tilt in the direction X Direction and θ Y The display may be configured to have a tilt function for adjusting the position in the direction.

[0035] Further, on the side surfaces of the Y stage 23 and the X stage 24, encoder systems 25 corresponding to the X direction, Y direction, and Z direction are arranged. The encoder system 25 irradiates a beam from an encoder head 27 onto an encoder scale 26, thereby measuring the positions of the Y stage 23 and the X stage 24 in real time. Then, the substrate control unit 10 positions the Y stage 23 and the X stage 24 based on the measurement values ​​of the encoder system 25.

[0036] When positioning the substrate 29 relative to the mold 19 , the alignment measurement unit 8 irradiates the mold 19 and the substrate 29 with light and detects alignment light 32 reflected by the mold 19 and the substrate 29 . This makes it possible to measure the relative positional deviation between the mold 19 and the substrate 29 by measuring the positions of the alignment mark (first mark) formed on the mold 19 and the alignment mark (second mark) formed on the substrate 29 within the substrate surface. The amount of relative positional misalignment measured here is used when the mold driving unit 31 moves the mold holding unit 20, or when the Y actuator 41 and X actuator 42 move the Y stage 23 and X stage 24 to reduce the relative positional misalignment between the mold 19 and the substrate 29. Furthermore, by deforming the shape of the pattern area 19a of the mold 19 and the shot area on the substrate 29 using a shape correction unit (not shown), it is also possible to reduce the relative positional deviation between the mold 19 and the substrate 29.

[0037] The supply unit 5 supplies (applies) the imprint material 30 onto the surface of the substrate 29 that has moved directly below it. The supply unit 5 may supply the imprint material 30 all at once onto the entire surface of the substrate 29, or may supply the imprint material 30 for each shot area arranged in a row, or for each shot area where the imprint process is performed. It should be noted that the supply unit 5 does not need to be provided when the imprint material 30 is supplied to the entire surface of the substrate 29 in advance before the substrate 29 is carried into the imprint apparatus 1 according to this embodiment.

[0038] The control unit including the mold control unit 7 and the substrate control unit 10 is configured by a computer including a CPU, memory, etc., and controls each unit of the imprint apparatus 1 according to a program stored in the memory. Specifically, the mold control unit 7 controls the operation and adjustment of each part of the imprint apparatus 1 , thereby controlling the imprint process for forming a pattern of the imprint material 30 on the substrate 29 .

[0039] The substrate control unit 10 also controls the substrate stage 4 to move the substrate stage 4 to a supply area of ​​the supply unit 5 for supplying the imprint material 30 to the substrate 29, or to a position for bringing the substrate 29 into contact with the mold 19. In addition, after the mold 19 and the substrate 29 are brought into contact with each other, the substrate control unit 10 issues commands to the Y actuator 41 and the X actuator 42 to align the substrate 29 by moving it relative to the mold 19 in the X and Y directions.

[0040] As shown in Figure 1, the imprinting apparatus 1 according to this embodiment includes a stage base on which the substrate stage 4 is placed, a bridge base on which the mold holding mechanism 3 is fixed, and a support pillar that is supported by the stage base and supports the bridge base. In addition, in the imprinting apparatus 1 according to this embodiment, a vibration isolator is placed on a base plate supported by the floor, and the vibration isolator supports the stage plate, thereby reducing vibrations propagating from the floor surface to the stage plate. Furthermore, the imprint apparatus 1 according to this embodiment also includes a mold transport unit (not shown) that transports the mold 19 from the outside to the mold holding mechanism 3, and a substrate transport unit (not shown) that transports the substrate 29 from the outside to the substrate stage 4.

[0041] Next, an operation performed after the mold 19 and the imprint material 30 on the substrate 29 are brought into contact with each other in the imprint process by the imprint apparatus 1 according to this embodiment will be described.

[0042] 2(a) and 2(b) are partially enlarged cross-sectional views showing the state when the mold 19 of the imprint apparatus 1 according to this embodiment and the imprint material 30 on the substrate 29 are in contact with each other.

[0043] Specifically, after the pattern area 19a of the mold 19 and the imprint material 30 on the substrate 29 come into contact with each other, the X stage 24 moves in the -X direction, for example, as shown in Figure 2(a), in order to reduce the deviation in the relative position between the mold 19 and the substrate 29 measured by the alignment measurement unit 8. Then, when the X stage 24 moves in the −X direction to align the mold 19 with the substrate 29, a force is applied to the pattern region 19a of the mold 19 along the shear direction (here, the X direction). As a result, the pattern area 19a of the mold 19 rotates around the Y axis, i.e., θ Y The image has a certain tilt in the direction.

[0044] At this time, in the imprinting apparatus 1 according to this embodiment, as shown in FIG. 2(b), the mold driving unit 31 tilts the mold holding unit 20, i.e., rotates it around the Y axis, thereby correcting the above-mentioned tilt in the pattern area 19a of the mold 19. This makes it possible to reduce the relative tilt between the pattern region 19a of the mold 19 and the substrate 29.

[0045] Here, the amount of positional fluctuation of the substrate stage 4 when reducing the relative positional misalignment between the mold 19 and the substrate 29 described above also includes the influence of deformation of the Y stage 23 and X stage 24, which are provided between the location where position measurement is performed on the substrate stage 4 and the substrate 29. In addition, the shear force applied to the pattern area 19a of the mold 19 by the movement of the substrate stage 4, and therefore the relative inclination between the pattern area 19a of the mold 19 and the substrate 29, and the tilt drive amount required of the mold holding unit 20 also depend on the movement distance and movement speed of the substrate stage 4 during the movement.

[0046] Therefore, in the imprint apparatus 1 according to this embodiment, the driving forces applied by the Y actuator 41 and the X actuator 42 to the Y stage 23 and the X stage 24 of the substrate stage 4 are fed back to the mold driving unit 31, thereby causing the mold driving unit 31 to tilt the mold holding unit 20.

[0047] FIG. 3 is a flowchart showing the imprint process in the imprint apparatus 1 according to this embodiment.

[0048] First, when the imprint process is started in the imprint apparatus 1 according to this embodiment, the imprint conditions are set (step S110). The imprint conditions (parameters) here include, for example, the material of the imprint material 30, the thickness of the imprint material 30 on the substrate surface, the size of the shot areas, the layout of the shot areas, and the order in which the shot areas are subjected to the imprint process.

[0049] Then, in step S110, tilt correction coefficients, which will be described in detail below, are determined from the set imprint conditions. Specifically, in the imprint apparatus 1 according to this embodiment, in step S110, the tilt correction coefficient can be determined using the results of an imprint process that was previously performed under the same imprint conditions.

[0050] Therefore, when performing imprint processing under different imprint conditions for the first time, it is preferable to confirm the results by performing the imprint processing under the different imprint conditions on a test substrate or the like in advance. In step S110, the tilt correction coefficient may be determined by performing a simulation based on the set imprint conditions.

[0051] Next, the substrate stage 4 is driven to move the substrate 29 to a position (supply area) where the supply unit 5 supplies the imprint material 30 to a shot area on the substrate 29 where a pattern is to be formed by the imprint process (step S111). Then, after the substrate stage 4 has moved to that position in step S111, the imprint material 30 is supplied onto that shot area by the supply unit 5 while the substrate 29 is being moved (step S112).

[0052] Next, the substrate stage 4 is driven to move the substrate 29 so that a predetermined shot area among the shot areas to which the imprint material 30 was supplied in step S112 is positioned opposite the pattern area 19a of the mold 19 (step S113). Then, the mold driving unit 31 is driven to lower the mold 19 so that the imprint material 30 on the predetermined shot area and the pattern area 19a of the mold 19 come into contact with each other (step S114, contact step).

[0053] Next, the alignment measurement unit 8 measures the amount of relative positional misalignment between the mold 19 and the substrate 29, and the Y stage 23 and X stage 24 are moved so as to reduce the measured amount of relative positional misalignment, thereby starting alignment between the mold 19 and the substrate 29 (step S115, start of the position correction process). That is, in step S115, alignment between the mold 19 and the substrate 29 is started based on the measurement results of the positions of the alignment marks formed on the mold 19 and the substrate 29, respectively, by the alignment measurement unit 8.

[0054] Then, in step S115, the values ​​of the driving forces of the Y actuator 41 and the X actuator 42 when moving the Y stage 23 and the X stage 24, that is, the command values ​​of the driving forces from the substrate control unit 10, are acquired (step S116, acquisition step).

[0055] Then, in order to correct the tilt of the pattern region 19a of the mold 19 caused by the movement of the Y stage 23 and X stage 24 in step S115, the mold holding part 20 is rotated by the mold driving part 31 (step S117, tilt correction step). The calculation of the amount of rotation of the mold holding unit 20, that is, the amount of tilt variation of the mold 19 in step S117 will be described in detail later.

[0056] Thereafter, the alignment between the mold 19 and the substrate 29 by the movement of the Y stage 23 and the X stage 24 is completed (step S118, end of the position correction process).

[0057] Next, the illumination unit 2 irradiates the imprint material 30 on the predetermined shot area of ​​the substrate 29 with the curing light 12, thereby performing exposure (step S119). After exposure in step S119, the mold driving unit 31 is driven to lift the mold 19 so that the mold 19 is separated from the imprint material 30 on the predetermined shot area of ​​the substrate 29 (step S120). As a result, a pattern made of the hardened imprint material 30 is formed on the predetermined shot area of ​​the substrate 29.

[0058] Next, it is determined whether the exposure processing of steps S113 to S120 has been performed on all shot areas of the substrate 29 on which the pattern is to be formed (step S121). If there is a shot area for which the exposure process has not been performed (No in step S121), the process returns to step S113, and the exposure process is performed on that shot area. On the other hand, if the exposure process has been performed on all the shot areas on the substrate 29 (Yes in step S121), the process proceeds to step S122.

[0059] In step S122, it is determined whether the imprint conditions set in step S110, i.e., the material of the imprint material 30, the film thickness of the imprint material 30, the size of the shot area, the layout of the shot area, the order in which the imprint process is performed, etc., are new conditions. If the imprint conditions are not new conditions (No in step S122), the imprint processing for the substrate 29 is ended. On the other hand, if the imprint conditions are new conditions (Yes in step S122), the process proceeds to step S123.

[0060] In step S123, in order to calculate the tilt correction coefficient under the new imprint conditions, the amount of misalignment of the overlay position on the substrate 29 on which the pattern of the imprint material 30 is formed is confirmed. Specifically, a high-magnification scope (not shown) installed in the imprinting apparatus 1 is used to measure the positional misalignment of each mark formed in the shot area of ​​the substrate 29 on which the pattern of the imprinting material 30 is formed. However, without being limited to this, in step S123, after the substrate 29 on which the pattern of the imprint material 30 has been formed is removed from the imprint apparatus 1, the positional deviation amount of each mark formed within the shot area of ​​the substrate 29 may be measured using a measuring device provided outside the imprint apparatus 1.

[0061] The amount of misalignment measured in step S123 includes several components such as a shift component, an intensity component, a twist component, a rotation component, and a tilt component. Here, among such components, the tilt component within the substrate surface that affects distortion within the shot area is extracted. The reason for this is that under specified imprint conditions, for example, when the tilt variation of mold 19 is 1 microradian, the amount of distortion in the shot area changes by 0.5 nanometers, that is, it is known that the amount of distortion variation in the shot area depends on the tilt variation of mold 19.

[0062] Therefore, in the imprint apparatus 1 according to this embodiment, the amount of tilt variation of the mold 19 is roughly calculated from the magnitude of distortion within the shot area. In addition, when the material of the imprint material 30 is new under the imprint conditions, it is better to confirm the relationship between distortion and tilt variation amount, for example, by performing an exposure process on each of multiple substrates 29 while varying the tilt variation amount of the mold 19.

[0063] As described above, in step S123, the distortion in the shot area is extracted from the measured amount of misalignment of the overlay position on the substrate 29, and the amount of tilt variation of the mold 19 is roughly calculated from the distortion in the extracted shot area. Then, the drive forces of the Y actuator 41 and the X actuator 42 acquired in step S116 and the estimated tilt fluctuation amount of the mold 19 are compared with each other.

[0064] Specifically, the driving force in the X direction by the X actuator 42 and the corresponding tilt fluctuation amount of the mold 19, that is, the angle with respect to the X direction (angle in the rotation direction around the Y axis), are respectively expressed as F X and T X Let's say. Similarly, the driving force in the Y direction by the Y actuator 41 and the corresponding tilt fluctuation amount of the mold 19, that is, the angle with respect to the Y direction (angle in the rotation direction around the X axis), are respectively expressed as F Y and T Y Let's say.

[0065] At this time, by substituting these values ​​into the following equations (1) and (2), the proportional coefficient, i.e., the tilt correction coefficient C X and C Y is calculated (step S124, determination step). T X =C X ×F X ···(1) T Y =C Y ×F Y ···(2)

[0066] Here, the tilt variation amount T X and T Y can be calculated as the driving force applied to each of the multiple actuators provided in the mold driving unit 31. In addition, the driving forces F of the X actuator 42 and the Y actuator 41 are X and F Y can be calculated as a command value from the substrate control unit 10.

[0067] Here, the tilt correction coefficient C X and C Y are constants that are not affected by other axes. In addition, in the above, the tilt correction coefficient C X and C Y However, the present invention is not limited to this.

[0068] For example, by performing the least squares method collectively on all shot areas on the substrate 29 that have been subjected to the imprint processing, the tilt correction coefficient C X and C Y may be determined. In addition, the tilt correction coefficient C X and C Y may be determined. That is, for example, the tilt correction coefficient C is set so that the error between each shot area where the imprint processing is performed on the whole is minimized. X and C Y may be determined. In addition, the tilt correction coefficient C is set so that the error between each shot area where the imprint processing is performed for the predetermined partial area is minimized. X and C Y may be determined.

[0069] As an example, the driving force F in the X direction under a given imprint condition is X is 3 Newtons, and the tilt fluctuation amount T X was 1.5 microradians, and by substituting them into equation (1), C X =0.5 microradians / Newton.

[0070] Then, the tilt correction coefficient C for tilt correction in the mold 19 calculated in step S124 is X and C Y is reflected in the imprint conditions set in step S110.

[0071] FIG. 4 shows an example of the time dependency of the driving force F of the X actuator 42 and the tilt T of the mold holding part 20 when moving the X stage 24 in steps S115 to S118 of the imprint process by the imprint apparatus 1 according to this embodiment. The time dependency shown here also applies to the driving force of the Y actuator 41 when moving the Y stage 23.

[0072] As shown in FIG. 4, when the mold 19 is being lowered in step S114, a predetermined driving force F1 is generated by the X actuator 42 to stop the substrate stage 4 directly below the mold 19. In step S114, the inclination T of the mold holding part 20 is set to T1.

[0073] Next, after the mold 19 and the substrate 29 come into contact with each other, in step S115, the movement of the X stage 24 is started, and a shear force is generated in the X stage 24 in the shear direction (X direction), so that the driving force F of the X actuator 42 begins to change over time. Then, at time t immediately before step S118 at which the movement of the X stage 24 is terminated, a At this point, a predetermined driving force F2 is generated by the X actuator 42.

[0074] Then, the information on the driving force F2 acquired in step S116 is sent from the substrate control unit 10 to the mold control unit 7, and the mold control unit 7 calculates the tilt fluctuation amount T X The mold holder 20 is rotated only. As a result, the tilt T of the mold holding unit 20 changes from T1 to T2. The timing at which the mold driving unit 31 rotates the mold holding unit 20 is the time t a It is sufficient if it is within the period from when the driving force F by the X actuator 42 is measured in step S116 until exposure is started in step S119.

[0075] In this way, by correcting the relative tilt between the mold 19 and the substrate 29 by changing the tilt of the mold holding portion 20 before starting exposure, the effect of the relative tilt, i.e., distortion in the pattern of the imprint material 30 formed on the substrate 29, can be reduced.

[0076] As described above, in the imprint process in the imprint apparatus 1 according to this embodiment, the driving forces F by the Y actuator 41 and the X actuator 42 in steps S115 and S116 are X and F Y and the tilt correction coefficient C determined from the imprint conditions. X and C Y Therefore, the tilt variation amount T of type 19 X and T Y is determined. Then, the tilt fluctuation amount T determined in step S117 X and T Y By rotating the mold 19 by only this amount and then performing the exposure process, distortion caused by the relative tilt between the mold 19 and the substrate 29 is reduced, thereby improving the overlay accuracy.

[0077] The calculation of the tilt correction coefficient in step S124 is not limited to the method using the actual measurement values ​​as described above, but may be performed based on the results of a simulation. Furthermore, in the imprint apparatus 1 according to this embodiment, the tilt correction coefficient is calculated in step S124 when the imprint conditions are new, but this is not limiting. That is, in the imprint apparatus 1 according to this embodiment, step S124 may be performed when it is desired to increase the precision of the tilt correction coefficient under the same imprint conditions.

[0078] In the above, as shown in the formulas (1) and (2), the tilt fluctuation amount T X and T Y The driving force F by the Y actuator 41 and the X actuator 42 X and F Y The following are determined, but are not limited to: That is, the material of the imprint material 30 is appropriately changed, or the positions of the Y stage 23 and the X stage 24 are measured at a location close to the substrate 29, thereby making the deformation of the Y stage 23 and the X stage 24 sufficiently small. In this case, the driving force F by the Y actuator 41 and the X actuator 42 X and F Y Instead, the amount of change in the positions of the Y stage 23 and the X stage 24, that is, the amount of tilt change T of the mold 19 from the amount of drive of the Y stage 23 and the X stage 24, is calculated. X and T Y can be determined and fed back to the mold driving unit 31.

[0079] Also, in the above description, control for reducing the tilt fluctuation of the mold 19 that occurs when the substrate stage 4 is driven so as to reduce the amount of relative positional deviation between the mold 19 and the substrate 29 in step S115 has been described. However, the imprinting apparatus 1 according to this embodiment is not limited to this, and can also be applied to cases where the tilt fluctuation amount of the mold 19 is calculated and corrected from the shear force in the shear direction (X direction and Y direction) applied to the substrate 29 by bringing the mold 19 and the imprinting material 30 on the substrate 29 into contact with each other.

[0080] In other words, when the pattern area 19a of the mold 19 comes into contact with the imprint material 30 on the substrate 29 while the mold 19 is tilted relative to the substrate 29, in addition to the driving force for stopping the substrate stage 4, it is thought that a shear force in the shear direction (X direction and Y direction) due to the contact will be applied to the substrate 29. In this case, based on the above discussion, the relative inclination of the mold 19 with respect to the substrate 29, that is, the amount of tilt variation of the mold 19, can be calculated from the applied shear force. Then, by rotating the mold 19 so as to correct the calculated tilt variation amount, the relative tilt between the mold 19 and the substrate 29 can be reduced.

[0081] In other words, in the imprint apparatus 1 according to this embodiment, the pattern area 19a of the mold 19 and the imprint material 30 on the substrate 29 are brought into contact with each other, and then the driving forces of the Y actuator 41 and the X actuator 42 are obtained. Then, the tilt fluctuation amount of the mold 19 is calculated from the magnitude of the driving force thus obtained, and the mold 19 is rotated so as to correct the calculated tilt fluctuation amount, thereby reducing the relative tilt between the mold 19 and the substrate 29. In the above, the driving force F by the Y actuator 41 and the X actuator 42 X and F Y is calculated as a command value from the substrate control unit 10, but is not limited to this and may be measured by providing a strain gauge or the like on the substrate 29 or the Y stage 23 that holds the substrate 29.

[0082] [Second embodiment] FIG. 5 is a flowchart showing the imprint process in the imprint apparatus according to the second embodiment. The imprinting apparatus according to this embodiment has the same configuration as the imprinting apparatus 1 according to the first embodiment, so the same components are given the same reference numerals and the description thereof will be omitted.

[0083] As shown in FIG. 5, the imprinting process in the imprinting apparatus according to this embodiment is the same as the imprinting process in the imprinting apparatus 1 according to the first embodiment, except that step S215 is performed instead of steps S115 to S117. Therefore, in the following, the description of steps S110 to S114 and steps S118 to S124 will be omitted, and only step S215 will be described.

[0084] In step S215, the movement of the Y stage 23 and the X stage 24 to reduce the relative positional misalignment between the mold 19 and the substrate 29 and the rotation of the mold holding part 20 to correct the tilt of the mold 19 in the pattern area 19a are performed in synchronization with each other.

[0085] That is, in step S215, after the Y stage 23 and the X stage 24 have been moved, the mold holding part 20 is rotated. Then, in order to reduce the relative positional misalignment between the mold 19 and the substrate 29 that occurs again due to the rotation of the mold holding unit 20, the Y stage 23 and the X stage 24 are moved, and then the mold holding unit 20 is rotated in order to correct the tilt in the pattern area 19a of the mold 19 that occurs again due to the movement of the Y stage 23 and the X stage 24.

[0086] This repetitive operation is carried out until the relative positional deviation between the mold 19 and the substrate 29 becomes equal to or less than a predetermined threshold value, and the relative tilt between the mold 19 and the substrate 29 becomes equal to or less than a predetermined threshold value. However, without being limited to this, the above-mentioned repeated operation may be performed until the amount of change over time in the relative positional deviation between the mold 19 and the substrate 29 becomes equal to or less than a predetermined threshold value and the amount of change over time in the relative tilt between the mold 19 and the substrate 29 becomes equal to or less than a predetermined threshold value.

[0087] Here, in step S215, the above-described rotational operation of the mold holding part 20 may be performed throughout the entire period from the start of movement of the Y stage 23 and the X stage 24 to the end of movement. In step S215, the above rotational operation of the mold holding part 20 may be performed intermittently, for example, every 0.1 seconds, from the start to the end of the movement of the Y stage 23 and X stage 24. In step S215, the case where the movement and the rotation are synchronized with each other so that the rotation operation of the mold holding part 20 is performed only once just before the end of the movement of the Y stage 23 and the X stage 24 corresponds to the imprint processing in the imprint apparatus 1 of the first embodiment.

[0088] As described above, in the imprinting process in the imprinting apparatus according to this embodiment, the tilt fluctuation amount T x and T Y Determine. Then, by performing an exposure process after the relative positional deviation between the mold 19 and the substrate 29 becomes equal to or less than a predetermined threshold value and the relative tilt between the mold 19 and the substrate 29 becomes equal to or less than a predetermined threshold value, the distortion caused by the relative tilt between the mold 19 and the substrate 29 is reduced, thereby improving the overlay accuracy.

[0089] [Production method] The pattern of the cured product formed using the imprint apparatus according to this embodiment is used permanently in at least a part of various articles, or temporarily when manufacturing various articles. The term "articles" as used herein includes electric circuit elements, optical elements, MEMS, recording elements, sensors, molds, etc.

[0090] 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 sensor, and FPGA. The mold also includes a mold for imprinting.

[0091] The pattern of the cured material formed using the imprint apparatus according to this embodiment is used as it is as at least a part of the constituent member of the above-mentioned article. Alternatively, the pattern of the cured product is temporarily used as a resist mask, and after etching or ion implantation or the like is performed in the substrate processing step, the resist mask is removed.

[0092] Although the preferred embodiments have been described above, the present invention is not limited to these embodiments and various modifications and changes are possible within the scope of the gist thereof. [Explanation of symbols]

[0093] 1 Imprinting device 7 Type control section (control section) 10. Board control unit (control unit) 19-inch 20 type holding part 23 Y stage (substrate holder) 24 X stage (substrate holder) 29 Circuit Board 30 Imprint material 31-type drive unit 41 Y actuator (substrate drive unit) 42 X actuator (board drive unit)

Claims

1. An imprinting apparatus for forming a pattern in an imprint material on a substrate using a mold, a mold holding unit that holds the mold; a mold driving unit that moves the mold holding unit; a substrate holder for holding the substrate; a substrate driving unit that moves the substrate holding unit; a control unit that controls the mold driving unit and the substrate driving unit; Equipped with The control unit a contacting step of controlling at least one of the mold driving unit and the substrate driving unit so that the mold and the imprint material on the substrate come into contact with each other; an acquiring step of acquiring information about the driving force of the substrate driving unit in a first direction parallel to the substrate surface after the contacting step; a tilt correction step of reducing the relative tilt between the mold and the substrate by the mold driving unit based on the information on the driving force acquired in the acquisition step; An imprinting apparatus comprising:

2. a position measurement unit that measures the positions of a first mark formed on the mold and a second mark formed on the substrate in a plane parallel to the substrate surface, after performing the contact step, the control unit causes the position measurement unit to measure the relative position of the first mark and the second mark, and performs a position correction step of moving the substrate holding unit within the plane using the substrate driving unit based on the measured relative position; The imprint apparatus according to claim 1 , wherein the control unit performs the acquiring step after performing the position correcting step.

3. The imprint apparatus according to claim 1 or 2, characterized in that when the magnitude of the angle by which the mold holding unit is rotated in the tilt correction process is T, the magnitude of the driving force acquired in the acquisition process is F, and a proportionality coefficient is C, and the equation is T = C x F, the control unit performs a determination process to determine the proportionality coefficient based on predetermined parameters.

4. 4. The imprint apparatus according to claim 3, wherein the predetermined parameters include at least one of the material of the imprint material, the thickness of the imprint material on the substrate, the size of the shot area on the substrate in which the pattern of the imprint material is formed, the layout of the shot area on the substrate, and the order in which the pattern of the imprint material is formed on the substrate.

5. The imprinting apparatus according to claim 3 or 4, characterized in that the control unit performs the determination process based on the results of a previous process for forming a pattern of the imprinting material in which the specified parameters are the same.

6. 5. The imprint apparatus according to claim 3, wherein the control unit performs the determination step based on a result of a simulation using the predetermined parameters.

7. 7. The imprint apparatus according to claim 1, wherein the control unit performs the tilt correction step after completing the acquisition step.

8. The imprint apparatus according to any one of claims 1 to 6, characterized in that the control unit repeatedly performs the acquisition process and the tilt correction process until the deviation in the relative position between the mold and the substrate becomes equal to or less than a predetermined threshold and the relative tilt between the mold and the substrate becomes equal to or less than a predetermined threshold.

9. forming a pattern of imprint material on a substrate using a mold by using the imprint apparatus according to any one of claims 1 to 8; processing the substrate on which the pattern is formed; and manufacturing an article from the processed substrate.

10. A method for forming a pattern in an imprint material on a substrate using a mold in an imprint apparatus including a mold holding unit that holds a mold, a mold driving unit that moves the mold holding unit, a substrate holding unit that holds a substrate, and a substrate driving unit that moves the substrate holding unit, the method comprising: a contacting step of controlling at least one of the mold driving unit and the substrate driving unit so that the mold and the imprint material on the substrate come into contact with each other; an acquiring step of acquiring information about the driving force of the substrate driving unit in a first direction parallel to the substrate surface after the contacting step; a tilt correction step of reducing the relative tilt between the mold and the substrate by the mold driving unit based on the information on the driving force acquired in the acquisition step; A method comprising:

11. the imprint apparatus includes a position measurement unit that measures the positions of a first mark formed on the mold and a second mark formed on the substrate in a plane parallel to a surface of the substrate, the method includes, after the contacting step, a position correcting step of measuring a relative position between the first mark and the second mark by the position measuring unit, and moving the substrate holding unit within the plane based on the measured relative position by the substrate driving unit; The method according to claim 10 , wherein the acquiring step is performed after the position correcting step.

12. The method according to claim 10 or 11, characterized in that it includes a determination step of determining a proportionality coefficient based on predetermined parameters, where T is the angle by which the mold holding unit is rotated in the tilt correction step, F is the magnitude of the driving force acquired in the acquisition step, and C is a proportionality coefficient, and the coefficient is expressed as T = C × F.

13. 13. The method of claim 12, wherein the predetermined parameters include at least one of the material of the imprint material, the thickness of the imprint material on the substrate, the size of the shot area on the substrate in which the pattern of the imprint material is formed, the layout of the shot area on the substrate, and the order in which the pattern of the imprint material is formed on the substrate.

14. 14. A method according to claim 12 or 13, wherein the determining step is based on the results of a previous process for forming a pattern of the imprint material, in which the predetermined parameters are the same.

15. 14. The method according to claim 12, wherein the determining step is performed based on the results of a simulation using the predetermined parameters.

16. 16. The method according to claim 10, wherein the tilt correction step is performed after the acquisition step is completed.

17. 16. The method according to claim 10, wherein the acquisition step and the tilt correction step are repeatedly performed until the deviation of the relative position between the mold and the substrate becomes equal to or less than a predetermined threshold and the relative tilt between the mold and the substrate becomes equal to or less than a predetermined threshold.

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