Imprinting method, imprinting apparatus, and method for manufacturing articles

Abstract

It provides a technology that is advantageous for aligning molds and substrates. [Solution] An imprint method is provided for forming a pattern on an imprint material disposed on at least one layer formed on a substrate using a mold, comprising: a first step of acquiring gas information relating to gas in a storage space for storing the substrate; a second step of determining the value of a control parameter for controlling exposure to light irradiating the imprint material when the imprint material on the at least one layer of the substrate stored in the storage space and the mold are in contact, based on the gas information acquired in the first step; and a third step of performing the exposure according to the value of the control parameter determined in the second step.

Description

Technical Field

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

Background Art

[0002] As one of lithographic apparatuses for manufacturing devices, there is an imprint apparatus that performs an imprint process of forming a pattern made of a cured product of an imprint material by bringing a mold into contact with the imprint material on a substrate and curing the imprint material. The imprint process includes a contact step of bringing the imprint material on the substrate into contact with the mold, an alignment step of aligning the mold and the substrate after the contact step, and a curing step of curing the imprint material after the alignment step. Also, before performing the imprint process, an underlayer and an adhesion layer are disposed (applied) on the substrate.

[0003] Regarding an imprint apparatus, a technique for reducing relative vibration between a mold and a substrate in a state where the imprint material on the substrate and the mold are in contact (contact state) has been proposed (see Patent Document 1). Patent Document 1 discloses an imprint apparatus having an adjustment unit that adjusts the viscosity of the imprint material and a control unit that changes a parameter value for controlling the adjustment unit in accordance with a change in control information for controlling an alignment operation between the mold and the substrate in the contact state.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In imprint lithography equipment, a pre-exposure process is performed during the alignment stage, in which light in a wavelength range with light absorption sensitivity is irradiated onto the imprint material to increase its viscosity, thereby reducing relative vibrations between the mold and the substrate. However, if the substrate with the underlay and adhesion layers is stored in a storage space, a high oxygen concentration in the storage space will cause oxygen to be absorbed by the underlay and adhesion layers, inhibiting the hardening of the imprint material and preventing the viscosity of the imprint material from being sufficiently increased during pre-exposure. As a result, the relative vibrations between the mold and the substrate cannot be reduced as intended, leading to a decrease in the alignment accuracy between the mold and the substrate.

[0006] This invention has been made in view of the problems of the prior art, and its exemplary objective is to provide a technique that is advantageous for aligning a mold and a substrate. [Means for solving the problem]

[0007] To achieve the above objective, an imprint method as one aspect of the present invention is an imprint method for forming a pattern on an imprint material disposed on at least one layer formed on a substrate using a mold, characterized by comprising: a first step of acquiring gas information relating to gas in a storage space for storing the substrate; a second step of determining the value of a control parameter for controlling exposure to light irradiating the imprint material with light when the imprint material on the at least one layer of the substrate stored in the storage space and the mold are in contact, based on the gas information acquired in the first step; and a third step of performing the exposure according to the value of the control parameter determined in the second step.

[0008] Further objects or other aspects of the present invention will be revealed by embodiments described below with reference to the accompanying drawings. [Effects of the Invention]

[0009] According to the present invention, for example, it is possible to provide a technique that is advantageous for aligning a mold and a substrate. [Brief explanation of the drawing]

[0010] [Figure 1] This is a schematic diagram showing the configuration of the imprint system. [Figure 2] This is a schematic diagram showing the configuration of an imprint device. [Figure 3] This is a schematic diagram showing an example of the configuration of a light source unit. [Figure 4] This figure illustrates an example of fluctuations in relative vibration between the mold and the substrate. [Figure 5] This figure illustrates an example of fluctuations in relative vibration between the mold and the substrate. [Figure 6] This is a flowchart to explain how the imprint system works. [Figure 7] This figure shows an example of gas information and control parameter values ​​displayed in the user interface. [Figure 8] This is a diagram illustrating the manufacturing method of an article. [Modes for carrying out the invention]

[0011] The embodiments will be described in detail below with reference to the attached drawings. Note that the following embodiments do not limit the invention as defined in the claims. While the embodiments describe multiple features, not all of these features are essential to the invention, and the features may be combined in any way. Furthermore, in the attached drawings, identical or similar configurations are given the same reference numerals, and redundant descriptions are omitted.

[0012] Figure 1 is a schematic diagram showing the configuration of the imprint system 1000. The imprint system 1000 is a system for forming patterns on an imprint material on a substrate. The imprint system 1000 includes a coating device 100, a control device 300, and an imprint device 1.

[0013] The coating device 100 includes, for example, a spin coater or the like, and forms (coats) at least one layer on the surface of the substrate (on the substrate). At least one layer formed on the substrate includes an underlayer containing spin-on carbon (SOC), an adhesion layer for improving the adhesion between the imprint material and the substrate, and the like. The adhesion layer is formed, for example, on the underlayer.

[0014] The control device 300 is constituted by a computer (information processing device) including, for example, a CPU, a memory (storage unit), and the like. The control device 300 comprehensively controls each part of the imprint system 1000, that is, the coating device 100 and the imprint device 1, to operate the imprint system 1000.

[0015] The imprint device 1 is a lithography device that is adopted in a lithography process, which is a manufacturing process of devices such as semiconductor elements, liquid crystal display elements, and magnetic storage media as articles, and forms a pattern on a substrate. The imprint device 1 brings the imprint material disposed (supplied) on the substrate into contact with a mold, and by applying energy for curing to the imprint material, forms a pattern of a cured product on which the pattern of the mold is transferred.

[0016] As the imprint material, a material (curable composition) that cures when energy for curing is applied is used. As the energy for curing, electromagnetic waves, heat, or the like is used. The electromagnetic waves include, for example, light selected from the range of wavelengths of 10 nm or more and 1 mm or less, specifically, infrared rays, visible rays, ultraviolet rays, and the like.

[0017] The curable composition is a composition that cures by irradiation with light or heating. The photocurable composition that cures by irradiation with light contains at least a polymerizable compound and a photoinitiator, and may further contain a non-polymerizable compound or a solvent as necessary. The non-polymerizable compound is at least one selected from the group consisting of a sensitizer, a hydrogen donor, an internal mold release agent, a surfactant, an antioxidant, a polymer component, and the like.

[0018] The imprint material may be applied in a film form on the substrate by a spin coater or a slit coater. Further, the imprint material may be applied on the substrate in the form of droplets or in an island or film form formed by connecting a plurality of droplets by a liquid injection head. The viscosity of the imprint material (viscosity at 25°C) is, for example, 1 mPa·s or more and 100 mPa·s or less. END]]

[0019] For the substrate, glass, ceramics, metal, semiconductor, resin, etc. are used, and if necessary, a member made of a material different from the substrate may be formed on its surface. Specifically, the substrate includes a silicon wafer, a compound semiconductor wafer, quartz glass, etc.

[0020] In this specification and the accompanying drawings, directions are indicated in an XYZ coordinate system where the direction parallel to the surface on which the substrate is disposed is the XY plane. The directions parallel to the X-axis, Y-axis, and Z-axis in the XYZ coordinate system are defined as the X-direction, Y-direction, and Z-direction, respectively, and the rotations around the X-axis, Y-axis, and Z-axis are defined as θX, θY, and θZ, respectively. Control or drive related to the X-axis, Y-axis, and Z-axis means control or drive related to the directions parallel to the X-axis, Y-axis, and Z-axis, respectively. Further, control or drive related to the θX-axis, θY-axis, and θZ-axis means control or drive related to the rotations around the axes parallel to the X-axis, Y-axis, and Z-axis, respectively. Also, the position is information specified based on the coordinates of the X-axis, Y-axis, and Z-axis, and the orientation is information specified by the values of the θX-axis, θY-axis, and θZ-axis. Alignment of the mold and the substrate includes control of the position and / or orientation of at least one of the mold and the substrate. Further, alignment includes control for correcting or changing the shape of at least one of the mold and the substrate.

[0021] Figure 2 is a schematic diagram showing the configuration of the imprint apparatus 1. In this embodiment, the imprint apparatus 1 uses a mold M to perform an imprint process to form a pattern on an imprint material IM placed on at least one layer formed on a substrate S. The imprint process includes a contact step of bringing the imprint material IM on the substrate S into contact with the mold M, and an alignment step of aligning the mold M and the substrate S after the contact step. The imprint process also includes a curing step of curing the imprint material IM on the substrate S after the alignment step, and a release step of separating (pulling away) the mold M from the cured imprint material IM on the substrate S after the curing step.

[0022] The imprint apparatus 1 includes a substrate drive mechanism SD for holding and driving a substrate S, a base frame BF for supporting the substrate drive mechanism SD, and a mold drive mechanism MD for holding and driving a mold M. The substrate drive mechanism SD and the mold drive mechanism MD constitute a drive mechanism DRV that drives at least one of the substrate drive mechanism SD and the mold drive mechanism MD so that the relative position between the mold M and the substrate S is adjusted. The adjustment of the relative position between the mold M and the substrate S by the drive mechanism DRV includes driving for contact of the mold M with the imprint material IM on the substrate S, and driving for separation of the mold M from the cured imprint material IM (cured pattern) on the substrate S.

[0023] The substrate drive mechanism SD includes, for example, a substrate holding part SH that holds a substrate S, a substrate stage SS that supports the substrate holding part SH, and a substrate drive actuator SM that drives the substrate stage SS (substrate S). The substrate drive mechanism SD is configured to drive the substrate S along multiple axes (for example, three axes: X axis, Y axis, and θZ axis; preferably six axes: X axis, Y axis, Z axis, θX axis, θY axis, and θZ axis). The position and orientation of the substrate S are controlled under the control of the control unit 7 based on the measurement results of the substrate measurement unit 29 that measures the position and orientation of the substrate S.

[0024] The mold drive mechanism MD includes a mold holder MH that holds the mold M, and a mold drive actuator MM that drives the mold holder MH (mold M). The mold holder MH may include a mold deformation mechanism that deforms the mold M. The mold deformation mechanism deforms the mold M, for example, by applying force to the sides of the mold M. The mold drive mechanism MD is configured to drive the mold M around a plurality of axes (for example, three axes: Z axis, θX axis, and θY axis; preferably six axes: X axis, Y axis, Z axis, θX axis, θY axis, and θZ axis).

[0025] The mold M has a pattern region PR on which a pattern to be transferred to the imprint material IM on the substrate S is formed during the imprint process. The mold driving mechanism MD includes a pressure adjustment unit PC that adjusts the pressure in the space SP on the back side of the mold M (opposite the pattern region PR) to deform the mold M (and its pattern region PR) into a convex shape toward the substrate S or flatten it. For example, the pressure adjustment unit PC starts contact between the imprint material IM on the substrate S and the pattern region PR while the mold M is deformed into a convex shape toward the substrate S, and adjusts the pressure in the space SP so that the contact area between the imprint material IM and the pattern region PR gradually expands.

[0026] The imprint apparatus 1 includes a dispenser 5 for placing (supplying or applying) the imprint material IM onto the substrate S. However, the imprint material IM may be placed onto the substrate S by an external device of the imprint apparatus 1.

[0027] The imprint apparatus 1 has a curing light source unit 2 that, in the curing process, irradiates the imprint material IM between the substrate S and the mold M (the pattern area PR) with curing light 9 via an optical path LP to cure the imprint material IM. The optical path LP is an optical path that reaches the substrate S via the mold M and the imprint material IM.

[0028] The imprint apparatus 1 further includes a position measuring unit 12 that measures the relative position between alignment marks provided on the substrate S and alignment marks provided on the mold M. The position measuring unit 12 illuminates the alignment marks provided on the substrate S and alignment marks provided on the mold M with illumination light 15 and captures an image formed by these alignment marks. The illumination light 15 is light that is irradiated into the optical path LP, similar to the curing light 9.

[0029] The imprint apparatus 1 further includes an imaging unit 6 for detecting (acquiring) the contact state between the imprint material IM on the substrate S and the mold M (pattern area PR), or the state of filling the space between the substrate S and the mold M (pattern area PR) with the imprint material IM. The imaging unit 6 is also used to detect foreign matter between the substrate S and the mold M. The imaging unit 6 illuminates the laminated structure composed of the substrate S, the imprint material IM, and the mold M with observation light 18 and acquires an image formed by this laminated structure. The observation light 18 is light that is irradiated into the optical path LP, similar to the curing light 9 and illumination light 15.

[0030] The imprint apparatus 1 further includes a light source unit 20 that irradiates the optical path LP with modulated light 21. The light source unit 20 includes a spatial light modulator, as described later, and irradiates the optical path LP with modulated light 21, which is light modulated by the spatial light modulator. The modulated light 21 includes a first modulated light that partially hardens the imprint material IM, and a second modulated light that deforms the substrate S for alignment between the substrate S and the mold M. When the first modulated light irradiates the optical path LP, it is preferable that the second modulated light does not irradiate the optical path LP, and when the second modulated light irradiates the optical path LP, it is preferable that the first modulated light does not irradiate the optical path LP. However, both the first modulated light and the second modulated light may irradiate the optical path LP for a sufficiently short period of time during which the modulated light 21 irradiates the optical path LP. The first modulated light and the second modulated light are light whose wavelength ranges do not overlap. Also, the first modulated light and the second modulated light may be light that has peaks at different wavelengths.

[0031] The first modulated light has a wavelength that hardens the imprint material IM, specifically a wavelength that increases the viscosity (viscosity or viscoelasticity) of the imprint material IM. The first modulated light is modulated to increase the viscosity of the imprint material IM at any point in the shot region (pattern formation region) of the substrate S, thereby increasing the bonding force between the substrate S and the mold M by the imprint material IM. Irradiating the imprint material IM with the first modulated light (exposure) is called pre-exposure (vibration-controlled exposure). Pre-exposure is performed in parallel with the alignment process and contributes to improving the alignment accuracy between the mold M and the substrate S. When the bonding force between the substrate S and the mold M by the imprint material IM is weak (before irradiation with the first modulated light), the substrate S and the mold M vibrate individually due to disturbances, etc. (i.e., the relative vibration between the substrate S and the mold M is large). By irradiating the imprint material IM with a first modulated light to partially increase its viscosity and thereby enhance the bonding force between the substrate S and the mold M, relative vibrations between the substrate S and the mold M can be reduced, improving the alignment convergence. For example, increasing the viscosity of the imprint material IM by irradiating it with the first modulated light so that the magnitude of the shear force caused by the relative movement between the substrate S and the mold M is in the range of 0.5 to 1.0 N is effective in improving the alignment convergence. In contrast to pre-exposure, the curing process in which the imprint material IM on the substrate S is irradiated with curing light 9 to completely cure the imprint material IM is called the main exposure.

[0032] The second modulated light is light with a wavelength that does not cure the imprint material IM. The second modulated light is light that is modulated so that a light intensity distribution (illuminance distribution) is formed on the substrate S, specifically the shot area of ​​the substrate S, that deforms it into the target shape. When the second modulated light is irradiated onto the substrate S, a temperature distribution is formed on the substrate S, and this temperature distribution deforms the shot area of ​​the substrate S into the target shape. Once the shot area of ​​the substrate S is deformed into the target shape and alignment between the shot area of ​​the substrate S and the pattern area PR of the mold M is completed, a curing process is performed in which the imprint material IM is cured by irradiating it with curing light 9 from the curing light source unit 2.

[0033] The optical axes of the hardening light source unit 2, the position measurement unit 12, the imaging unit 6, and the light source unit 20 share an optical path LP. To achieve this, a composite mirror 22, dichroic mirrors 23 and 24 are provided. The composite mirror 22 transmits the observation light 18 and reflects the modulated light 21. The dichroic mirror 23 transmits the observation light 18 and the modulated light 21 and reflects the illumination light 15. The dichroic mirror 24 transmits the observation light 18, the modulated light 21, and the illumination light 15 and reflects the hardening light 9.

[0034] The imprint device 1 further includes a user interface UIF. The user interface UIF includes, for example, an input unit such as a keyboard for a user (administrator) to input commands to manage the imprint device 1, and an output unit such as a display device that visualizes and displays various information about the imprint device 1 (e.g., operating status). The user interface UIF may also consist of a touch panel having both input and output functions, or it may include an audio output device such as a speaker.

[0035] The imprint apparatus 1 further comprises a substrate storage space 1200 and a gas detector 1100. The substrate storage space 1200 is a space for accommodating and storing substrates S on which at least one layer has been formed by the coating apparatus 100, and is defined (embodied) by, for example, a FOUP or a chamber. The gas detector 1100 is located inside the substrate storage space 1200 (within the substrate storage space) and functions as an acquisition unit that acquires gas information regarding the gas in the substrate storage space. The gas detector 1100 includes, for example, a gas sensor that detects the type of gas and a gas concentration meter that detects the concentration of the gas, and acquires the type of gas in the substrate storage space and the concentration of the gas in the substrate storage space as gas information.

[0036] The imprint apparatus 1 further includes a control unit 7 that controls the drive mechanism DRV, pressure adjustment unit PC, dispenser 5, substrate measurement unit 29, curing light source unit 2, position measurement unit 12, imaging unit 6, light source unit 20, user interface UIF, gas detector 1100, etc. The control unit 7 is composed of, for example, a PLD (Programmable Logic Device) such as an FPGA (Field Programmable Gate Array), or an ASIC (Application Specific Integrated Circuit), or a general-purpose or dedicated computer with a program installed, or a combination of all or part of these.

[0037] The control unit 7 comprehensively controls each part of the imprint device 1 according to the program to operate the imprint device 1. The control unit 7 controls the imprint process, which forms a pattern on the imprint material IM on the substrate S using a mold M, and processes related to the imprint process. The control unit 7 may be configured integrally with the control device 300.

[0038] Figure 3 is a schematic diagram showing an example of the configuration of the light source unit 20. The light source unit 20 includes a first light source 121 that generates first light having a first wavelength range for generating first modulated light, and a second light source 122 that generates second light having a second wavelength range for generating second modulated light. The light source unit 20 also includes a digital mirror device (DMD) 133 as a spatial light modulator for generating first modulated light obtained by modulating the first light, and second modulated light obtained by modulating the second light. Furthermore, the light source unit 20 includes mirrors 125 and 126, an injection section 111, and an optical system 132 that direct the first light from the first light source 121 and the second light from the second light source 122 onto the DMD 133.

[0039] The light source unit 20 is configured, for example, by connecting an illumination unit 120 and a modulation unit 130 with an optical fiber 110. The illumination unit 120 includes a first light source 121, a second light source 122, a first controller 123, a second controller 124, and mirrors 125 and 126. The optical path of the first light from the first light source 121 and the optical path of the second light from the second light source 122 are shared by mirrors 125 and 126 and connected to the input end 111 of the optical fiber 110. The output end 112 of the optical fiber 110 is connected to the modulation unit 130.

[0040] The first controller 123 controls the first light source 121 under the control of the control unit 7. Control of the first light source 121 includes controlling the on / off state of the first light source 121 and controlling the intensity (illuminance) of the first light emitted by the first light source 121. For example, the first controller 123 includes a constant current circuit that supplies the first light source 121 with a current value according to a command value from the control unit 7. The first controller 123 may also include a drive circuit that drives the first light source 121 according to a command value and a photoelectric conversion sensor that receives a portion of the first light emitted by the first light source 121, and may have a configuration that feeds back the output of the photoelectric conversion sensor to the drive circuit.

[0041] The second controller 124 controls the second light source 122 under the control of the control unit 7. Control of the second light source 122 includes controlling the on / off state of the second light source 122 and controlling the intensity (illuminance) of the second light emitted by the second light source 122. For example, the second controller 124 includes a constant current circuit that supplies the second light source 122 with a current value according to a command value from the control unit 7. The second controller 124 may also include a drive circuit that drives the second light source 122 according to a command value, and a photoelectric conversion sensor that receives a portion of the second light emitted by the second light source 122, and may have a configuration that feeds back the output of the photoelectric conversion sensor to the drive circuit.

[0042] The control unit 7 controls the first light source 121 and the second light source 122 individually via the first controller 123 and the second controller 124. For example, the control unit 7 controls the first light source 121 and the second light source 122 such that when one of them is turned on, the other is turned off. In other words, when one of the first light from the first light source 121 and the second light from the second light source 122 is incident on the DMD 133, the other of the first and second light does not incident on the DMD 133. This is achieved, for example, by the control of the first light source 121 and the second light source 122 by the first controller 123 and the second controller 124, or by a mechanism that selectively blocks one of the first and second light.

[0043] Here, we will explain an example of wavelength assignment for each of the curing light 9, illumination light 15, observation light 18, and modulation light 21 (first modulation light and second modulation light). The curing light 9 is the light that cures the imprint material IM, and has any wavelength range within the range of 300 nm to 380 nm, but may also have a wavelength range of 300 nm or less.

[0044] The illumination light 15 is light used to detect (illuminate) alignment marks and has a wavelength range of, for example, 550 nm to 750 nm.

[0045] Observation light 18 is used to observe (acquire) the contact state between the imprint material IM and the mold M, and the state of filling the space between the substrate S and the mold M with the imprint material IM. For example, the wavelength range of observation light 18 is selected from the wavelength range of 400 nm to 480 nm, and does not overlap with the wavelength ranges of the curing light 9 and illumination light 15.

[0046] The modulated light 21 includes a first modulated light having a wavelength range that cures the imprint material IM, and a second modulated light having a wavelength range that does not cure the imprint material IM. The modulated light 21 is selected from a wavelength range similar to that of the observation light 18, for example, a wavelength range of 400 nm to 480 nm, so as not to overlap with the wavelength ranges of the curing light 9 and the illumination light 15. The first modulated light is generated by modulating the first light from the first light source 121 with the modulation unit 130 (DMD 133). The second modulated light is generated by modulating the second light from the second light source 122 with the modulation unit 130 (DMD 133). The wavelength of the first light emitted by the first light source 121 and the wavelength of the second light emitted by the second light source 122 can be selected (determined) from the upper limit of the wavelength range in which the imprint material IM hardens. For example, if the upper limit of the wavelength range in which the imprint material IM hardens is 440 nm, the wavelength of the first light emitted by the first light source 121 can be set to about 410 nm, and the wavelength of the second light emitted by the second light source 122 can be set to about 460 nm. The first light source 121 and the second light source 122 are preferably light sources that emit single-wavelength light with a narrow wavelength width, for example, laser diodes are preferred. Laser diodes are also advantageous in that they can be switched on and off at high speed. The first light source 121 and the second light source 122 may be composed of tunable light sources that can vary the wavelengths of the first and second light.

[0047] Light transmitted to the modulation unit 130 via the optical fiber 110 is incident on the DMD 133, which acts as a spatial light modulator, via the optical system 132. The optical system 132 includes, for example, a focusing optical system and an illumination system (e.g., a microlens array) that uniformizes the light from the focusing optical system to illuminate the DMD 133. The DMD 133 includes a plurality of micromirrors (not shown) that reflect light and a plurality of actuators that drive each of the plurality of micromirrors. Each actuator sets the corresponding micromirror to an angle of -12 degrees (ON state) or +12 degrees (OFF state) with respect to the arrangement plane of the plurality of micromirrors, according to a command from the control unit 7. Light reflected by the ON state micromirrors forms an image on the substrate S as modulated light via the optical system 134 (projection optical system) that makes the DMD 133 and the substrate S conjugate to the optical system. Light reflected by the OFF state micromirrors is reflected in a direction that does not reach the substrate S. When all micromirrors are turned ON, the area projected onto the substrate S (maximum illumination area) is larger than the size of the maximum pattern formation area of ​​the substrate S. The DMD133 can also be replaced with other spatial light modulators, such as liquid crystal displays (LCDs).

[0048] The optical system constituting the modulation section 130 needs to transmit both the first light (first modulation light) with a wavelength that hardens the imprint material IM and the second light (second modulation light) with a wavelength that does not harden the imprint material IM. Furthermore, in a typical DMD, the maximum light intensity that can be irradiated onto the micromirror array decreases at wavelengths below 420 nm, and even further, around 400 nm, which is the boundary between ultraviolet and visible light, the maximum light intensity that can be irradiated onto the micromirror array drops drastically to about 1 / 1000. Therefore, it is desirable to use a laser diode with a short wavelength width to bring the wavelengths of the first and second light closer to the upper limit of the wavelength range in which the imprint material IM hardens.

[0049] The control unit 7 controls the switching between the ON and OFF states of each micromirror of the DMD133 based, for example, on the light intensity distribution (illuminance distribution) to be formed on the substrate S. This switching control includes, for example, control over the time each micromirror is in the ON state and control over the time each micromirror is in the OFF state. The more micromirrors that are in the ON state, and the longer they remain ON, the greater the exposure amount can be applied to the shot area of ​​the substrate S.

[0050] The control unit 7 includes a memory for storing light intensity distribution data for modulating the first light to generate the first modulated light, and light intensity distribution data for modulating the second light to generate the second modulated light. The light intensity distribution data for modulating the first light to generate the first modulated light includes light intensity distribution data for increasing the viscosity of the imprint material IM at any location in the shot region of the substrate S to increase the bonding force between the substrate S and the mold M via the imprint material IM.

[0051] The configuration in which the modulation unit 130 is shared by the first light source 121 and the second light source 122 is advantageous in that it miniaturizes the modulation unit 130 or the light source unit 20 and simplifies the structure of the imprint device 1. This makes it easy to place the modulation unit 130 near the optical path LP. The configuration in which the illumination unit 120 and the modulation unit 130 are separated from each other is advantageous in that the illumination unit 120, which is a heat source, can be placed far away from the optical path LP of the imprint device 1. Alternatively, the illumination unit 120 and the modulation unit 130 may be placed in close proximity without using the optical fiber 110. The illumination unit 120 may also be incorporated into the modulation unit 130. Furthermore, the first light source 121 and the modulation unit 130 may be connected by a first optical fiber, and the second light source 122 and the modulation unit 130 may be connected by a second optical fiber. In this case, the optical path of the first light emitted from the first optical fiber and the optical path of the second light emitted from the second optical fiber are coupled.

[0052] Referring to Figure 4, the imprint process performed by the imprint apparatus 1, specifically the relative vibration (or fluctuation) between the mold M and the substrate S in a contact state where the mold M and the imprint material IM on the substrate S are in contact, will be explained. As shown in Figure 4, the imprint process includes a contact step, an alignment step, a curing step, and a demolding step.

[0053] As described above, the contact process is the process of bringing the imprint material IM on the substrate S into contact with the mold M (and its pattern area PR) using the drive mechanism DRV. The contact process is a period that begins, for example, with the contact between the imprint material IM on the substrate S and the pattern area PR of the mold M which has been deformed into a convex shape, and ends with the entire pattern area PR being returned to a flat state.

[0054] In the alignment process, based on the measurement results of the position measurement unit 12, the drive mechanism DRV drives at least one of the substrate S and the mold M so that the pattern area PR of the mold M and the shot area of ​​the substrate S are aligned. Also in the alignment process, based on the measurement results of the position measurement unit 12, the mold drive mechanism deforms the mold M so that the pattern area PR of the mold M and the shot area of ​​the substrate S are aligned.

[0055] The filling process proceeds in parallel with the alignment process. In the filling process, the imprint material IM between the pattern region PR of the mold M and the substrate S is filled into the recesses that constitute the pattern of the pattern region PR, and the space (void) that exists between the pattern region PR of the mold M and the substrate S disappears. In Figure 4, the alignment process and the filling process are shown as "Filling process and alignment process," and in one example, the filling process is started before the alignment process.

[0056] Pre-exposure is performed in parallel with the alignment process (and filling process), as shown in Figure 4. As described above, pre-exposure increases the viscosity of the imprint material IM at any location in the shot area of ​​the substrate S by irradiating the imprint material IM with first modulated light from the light source unit 20.

[0057] Furthermore, in this embodiment, as a pre-processing step for the imprinting process, a coating step, a storage step, and a transport step are performed, as shown in Figure 4. The coating step is a step in which at least one layer, including an underlayer and an adhesion layer, is formed on the substrate S in the coating apparatus 100. Hereinafter, the at least one layer formed on the substrate S will be referred to as the "underlayer". The storage step is a step in which, after the coating step and before transporting the substrate S with the underlayer formed on it to the imprint apparatus 1, the substrate S is placed in the substrate storage space 1200 and stored there. The transport step is a step in which, after the storage step, the substrate S stored in the substrate storage space 1200 is transported to the imprint apparatus 1.

[0058] The curing of imprint materials (IM) is caused by the polymerization reaction of polymerizable compounds triggered by radicals generated by photopolymerization initiators when exposed to light. Oxygen reacts with the radicals generated by the photopolymerization initiators when exposed to light, eliminating the radicals. This inhibits the polymerization reaction of the polymerizable compounds, which means that the curing of the imprint material (IM) is inhibited.

[0059] During the storage process, oxygen may be present inside the substrate storage space 1200 where the substrate S is stored. In this case, oxygen is absorbed into the underlayer formed on the substrate S stored in the substrate storage space 1200. The oxygen absorbed into the underlayer diffuses into the imprint material IM placed on the underlayer, thus inhibiting the hardening (increasing viscosity) of the imprint material IM during pre-exposure, and reducing the hardening during pre-exposure. In this embodiment, oxygen is used as an example to explain the polymerization reaction of polymerizable compounds, i.e., the type of gas that inhibits the hardening of the imprint material IM, but it is not limited to this. In other words, oxygen here is understood as a broad concept that includes the type of gas that inhibits the hardening of the imprint material IM.

[0060] Here, if the oxygen concentration in the substrate storage space 1200 is low, the amount of oxygen absorbed into the substrate layer (oxygen absorption) is small. In this case, as shown in Figure 4, pre-exposure can suppress the relative vibration (deviation) between the mold M and the substrate S to a target value (e.g., "0") during the filling and alignment processes. This is because the inhibition of the hardening of the imprint material IM due to oxygen absorbed into the substrate layer is weak, and pre-exposure can raise the viscosity of the imprint material IM to the pre-exposure target value. The pre-exposure target value is set to a value lower than the viscosity of the imprint material IM required to completely harden the imprint material IM in the hardening process (main exposure), i.e., the maximum viscosity.

[0061] On the other hand, as the oxygen concentration in the substrate storage space 1200 increases, the amount of oxygen absorbed by the substrate layer increases. In this case, as shown in Figure 5, pre-exposure makes it impossible to suppress the relative vibration (deviation) between the mold M and the substrate S to the target value (e.g., "0") during the filling and alignment processes. This is because the oxygen absorbed by the substrate layer strongly inhibits the hardening of the imprint material IM, and pre-exposure does not raise the viscosity of the imprint material IM to the pre-exposure target value. Thus, if the relative vibration between the mold M and the substrate S cannot be sufficiently reduced, the alignment accuracy between the mold M and the substrate S will decrease.

[0062] Therefore, in this embodiment, a technique is provided to control the exposure (pre-exposure and main exposure) of the imprint material IM on the substrate S while it is in contact with the mold M, according to the type and concentration of gas in the substrate storage space. According to this technique, the effect of inhibiting the hardening of the imprint material IM can be reduced and the decrease in alignment accuracy between the mold M and the substrate S can be suppressed.

[0063] The operation of the imprint system 1000 will be described with reference to Figure 6. This operation includes the coating process and the demolding process, and is performed by the control device 300 comprehensively controlling the coating device 100 and the control unit 7 comprehensively controlling each part of the imprint device 1. In the following, pre-exposure will be described as an exposure in which light is irradiated onto the imprint material IM while the imprint material IM and the mold M on the substrate S are in contact. However, the present invention is also applicable to this exposure in which light is irradiated onto the imprint material IM while the imprint material IM and the mold M on the substrate S are in contact.

[0064] In S602, the coating apparatus forms (coats) at least one layer, including an underlayer and an adhesion layer, onto the substrate S.

[0065] In S604, the substrate S, on which at least one layer was formed in S602, is placed in the substrate storage space 1200 and stored.

[0066] In S606, the gas detector 1100 is used to acquire gas information regarding the gas in the substrate storage space where the substrate S was stored in S604, for example, the type and concentration of the gas in the substrate storage space. Thus, S606 is a step (first step) to acquire gas information regarding the gas in the storage space where the substrate S, on which at least one layer is formed, is stored.

[0067] In S608, the substrate S stored in the substrate storage space 1200 is transported to the imprint device 1 via a substrate transport mechanism (not shown).

[0068] In S610, the control unit 7 determines the values ​​of control parameters for controlling pre-exposure as setting conditions (exposure conditions) for pre-exposure, based on the gas information acquired in S606, for example, the type and concentration of gas in the substrate storage space. The control parameters are parameters related to the control of the light (modulated light 21 in pre-exposure, curing light 9 in main exposure) irradiated onto the imprint material IM on the substrate S when the imprint material IM and the mold M are in contact. The control parameters include at least one of the illuminance, irradiation time, and wavelength of the light irradiated onto the imprint material IM. For example, if the gas in the substrate storage space is oxygen and its concentration is high, the illuminance of the light irradiated onto the imprint material IM is increased and / or the irradiation time of the light irradiated onto the imprint material IM is increased during pre-exposure. Thus, S610 is a step (second step) in which the values ​​of control parameters for controlling exposure, including pre-exposure and main exposure, which involve irradiating the imprint material IM with light, are determined based on gas information regarding the gas in the substrate storage space. In this embodiment, the control unit 7 also functions as a determination unit for determining the values ​​of the control parameters. In S610, the pre-exposure setting conditions, i.e., the values ​​of the control parameters, may be adjusted according to the material and film thickness of at least one layer, such as the underlayer or adhesion layer, formed on the substrate S. These may also be combined to determine the values ​​of the control parameters in order to reduce relative vibration between the mold M and the substrate S.

[0069] In step S612, a contact process is performed to bring the imprint material IM on the substrate S into contact with the mold M.

[0070] In S614, the control unit 7 performs pre-exposure to increase the viscosity of the imprint material IM by irradiating it with first modulated light from the light source unit 20 according to the control parameter values ​​determined in S606. For example, when controlling the illuminance and irradiation time of the first modulated light irradiated onto the imprint material IM, the DMD 133 is used, and when controlling the wavelength of the first modulated light irradiated onto the imprint material IM, the first light source 121, which is composed of a tunable light source, is used. In this embodiment, since pre-exposure is performed according to the control parameter values ​​determined based on gas information regarding the gas in the substrate storage space, the viscosity of the imprint material IM can be increased to the pre-exposure target value. Therefore, relative vibration between the mold M and the substrate S can be sufficiently reduced, and a decrease in the alignment accuracy between the mold M and the substrate S can be suppressed in the alignment process performed in parallel with the pre-exposure. Thus, S614 is a process (third step) in which light is irradiated onto the imprint material IM according to the determined control parameter values. In this embodiment, it also functions as a processing unit that performs pre-exposure.

[0071] In S616, the control unit 7 performs a curing process (main exposure) in which it irradiates the imprint material IM with curing light 9 from the curing light source unit 2 according to the value of a control parameter for controlling the main exposure, which is a setting condition (exposure condition) related to the main exposure, thereby curing the imprint material IM. Thus, S616 is also a process of performing exposure, in which light is irradiated onto the imprint material IM according to the value of the control parameter. Furthermore, in this embodiment, the control unit 7 functions as a processing unit that performs the main exposure.

[0072] In S618, a demolding process is performed to separate the mold M from the imprint material IM that was cured in S616.

[0073] In S620, it is determined whether the imprinting process for all shot areas of the substrate S has been completed. If the imprinting process for all shot areas has not been completed, the process proceeds to S612 to perform the imprinting process for the next shot area. On the other hand, if the imprinting process for all shot areas has been completed, the operation of the imprint system 1000 is terminated.

[0074] Thus, in this embodiment, depending on the type and concentration of the gas in the substrate storage space, at least one of the illuminance, irradiation time, and wavelength of the light irradiated onto the imprint material IM is controlled during pre-exposure so as to reduce relative vibration between the mold M and the substrate S. As a result, in the alignment process performed in parallel with pre-exposure, the viscosity of the imprint material IM is increased to the pre-exposure target value, making it possible to align the mold M and the substrate S with high precision and suppressing a decrease in alignment accuracy.

[0075] Furthermore, depending on the type and concentration of gas in the substrate storage space, it may not be possible to determine (calculate) the light intensity, irradiation time, and / or wavelength (control parameter values) that can raise the viscosity of the imprint material (IM) to the pre-exposure target value. In such cases, it is advisable to perform pre-exposure by adjusting the light intensity, irradiation time, and / or wavelength to the level that can maximize the viscosity of the imprint material (IM). It is also advisable to notify the user, for example, via the user interface (UIF), that the viscosity of the imprint material (IM) has not been sufficiently increased during pre-exposure, i.e., to display this information on the user interface (UIF).

[0076] Furthermore, when performing imprint processing on a substrate stored in a substrate storage space different from the substrate storage space 1200, the value of the control parameter, which is a setting condition for pre-exposure, should be changed according to the gas information regarding the gas in the different substrate storage space.

[0077] In S606, the gas information acquired by the gas detector 1100 located in the substrate storage space 1200 may be displayed on the user interface UIF as information provided to the user. For example, as shown in Figure 7(a), the control unit 7 controls the user interface UIF so that the type of gas and the gas concentration are displayed as gas information acquired from the gas detector 1100. Figure 7(a) shows an example of gas information displayed on the user interface UIF. Furthermore, if the user is aware of the gas information regarding the gas in the substrate storage space, the user interface UIF may be configured to accept user operations to input gas information. In this case, the control unit 7 may acquire the gas information regarding the gas in the substrate storage space via the user interface UIF.

[0078] Similarly, in S610, the values ​​of the control parameters determined by the control unit 7 may be displayed on the user interface UIF as information provided to the user. For example, as shown in Figure 7(b), the control unit 7 controls the user interface UIF so that the illuminance and irradiation time of the light irradiating the imprint material IM are displayed as values ​​of control parameters that control pre-exposure. Furthermore, as shown in Figure 7(b), it is preferable that the control unit 7 controls the user interface UIF so that the values ​​of the control parameters determined in S610, along with the values ​​of the previous control parameters, are displayed on the user interface UIF. This makes it easy for the user to understand how the values ​​of the control parameters have been updated (changed) according to the gas in the substrate storage space. It is also conceivable that the user may fine-tune the values ​​of the control parameters determined according to the gas in the substrate storage space (for example, by lowering the illuminance and increasing the irradiation time). In this case, the user interface UIF should be configured to accept user operations to adjust the values ​​of the control parameters. Figure 7(b) shows an example of the values ​​of the control parameters displayed on the user interface UIF.

[0079] The pattern of the cured material formed using the imprint apparatus 1 (imprint system 1000) in this embodiment is used permanently on at least a part of various articles, or temporarily when manufacturing various articles. Articles include electrical circuit elements, optical elements, MEMS, recording elements, sensors, or molds. Examples of electrical circuit elements include volatile or non-volatile semiconductor memories such as DRAM, SRAM, flash memory, and MRAM, as well as semiconductor elements such as LSI, CCD, image sensors, and FPGAs. Examples of molds include molds for imprinting.

[0080] The pattern of the cured material is either used as is as a component of at least some of the articles described above, or temporarily used as a resist mask. After etching or ion implantation is performed during the substrate processing process, the resist mask is removed.

[0081] Next, we will explain the specific manufacturing method of the product. As shown in Figure 8(a), a substrate such as a silicon wafer with a workpiece material such as an insulator formed on its surface is prepared, and then an imprint material is applied to the surface of the workpiece material by an inkjet method or the like. Here, we show how multiple droplet-shaped imprint materials are applied to the substrate.

[0082] As shown in Figure 8(b), the mold for imprinting is positioned so that the side with the raised and recessed pattern faces the imprint material on the substrate. As shown in Figure 8(c), the substrate to which the imprint material has been applied and the mold are brought into contact, and pressure is applied. The imprint material fills the gap between the mold and the workpiece. In this state, when light is shone through the mold as curing energy, the imprint material hardens.

[0083] As shown in Figure 8(d), after the imprint material has hardened, when the mold and substrate are separated, a pattern of the hardened imprint material is formed on the substrate. In this pattern, the recesses of the mold correspond to the protrusions of the hardened material, and the protrusions of the mold correspond to the recesses of the hardened material. In other words, the pattern of the mold's irregularities has been transferred to the imprint material.

[0084] As shown in Figure 8(e), when etching is performed using the cured material pattern as an etching-resistant mask, the parts of the workpiece surface where there is no cured material, or where a thin layer remains, are removed, forming grooves. As shown in Figure 8(f), when the cured material pattern is removed, an article with grooves formed on the surface of the workpiece can be obtained. Here, the cured material pattern was removed, but it may also be used without removal after processing, for example, as an interlayer insulating film included in semiconductor devices, i.e., as a component of the article.

[0085] The disclosures herein include the following imprinting methods, imprinting apparatuses, and methods for manufacturing articles.

[0086] (Item 1) An imprint method for forming a pattern on an imprint material placed on at least one layer formed on a substrate using a mold, A first step is to acquire gas information regarding the gas in the storage space where the substrate is stored, A second step involves determining the value of a control parameter for controlling exposure to irradiate light onto the imprint material while the imprint material on at least one layer of the substrate stored in the storage space is in contact with the mold, based on the gas information obtained in the first step; A third step involves performing the exposure according to the value of the control parameter determined in the second step, An imprinting method characterized by having the following:

[0087] (Item 2) The aforementioned exposure is Before curing the imprint material, pre-exposure is performed by irradiating the imprint material with light to increase its viscosity, Following the aforementioned pre-exposure, the main exposure is performed in which light is irradiated onto the imprint material to cure the imprint material, including, The imprinting method described in item 1, characterized by the features described herein.

[0088] (Item 3) In the second step, the values ​​of the control parameters for controlling the pre-exposure are determined. In the third step described above, the pre-exposure is performed. The imprinting method described in item 2, characterized by the features described herein.

[0089] (Item 4) The imprint method according to item 2 or 3, characterized in that the pre-exposure is performed in parallel with the alignment of the mold and the substrate in the aforementioned state.

[0090] (Item 5) The imprint method according to any one of items 1 to 4, characterized in that the first step involves obtaining the gas information by detecting the gas using a gas detector placed in the storage space.

[0091] (Item 6) The imprinting method according to any one of items 1 to 5, characterized in that the gas information includes the type of gas and the concentration of the gas.

[0092] (Item 7) The imprint method according to any one of items 1 to 6, characterized in that the gas contains oxygen.

[0093] (Item 8) The imprint method according to any one of items 1 to 7, characterized in that the control parameter includes at least one of the illuminance, irradiation time, and wavelength of the light irradiated onto the imprint material.

[0094] (Item 9) The imprint method according to any one of items 1 to 8, further comprising the step of displaying the gas information acquired in the first step on a user interface.

[0095] (Item 10) The imprint method according to any one of items 1 to 9, further comprising the step of displaying the value of the control parameter determined in the second step on a user interface.

[0096] (Item 11) The imprint method according to any one of items 1 to 10, characterized in that the at least one layer contains spin-on carbon.

[0097] (Item 12) An imprint apparatus that uses a mold to form a pattern on an imprint material placed on at least one layer formed on a substrate, An acquisition unit that acquires gas information regarding the gas in the storage space where the substrate is stored, Based on the gas information acquired by the acquisition unit, a determination unit determines the value of a control parameter for controlling exposure to irradiate light onto the imprint material when the imprint material on at least one layer of the substrate stored in the storage space is in contact with the mold. A processing unit that performs the exposure according to the control parameter value determined by the determination unit, An imprinting device characterized by having [a certain feature].

[0098] (Item 13) The imprint apparatus according to item 12, further comprising a user interface for displaying the gas information and the values ​​of the control parameters.

[0099] (Item 14) The imprint apparatus according to item 12 or 13, characterized in that the user interface accepts user operations to adjust the value of the control parameter.

[0100] (Item 15) A step of forming a pattern on a substrate using the imprint method described in any one of items 1 to 11, A step of processing the substrate on which the pattern has been formed in the above step, A process for manufacturing an article from the processed substrate, A method for manufacturing an article, characterized by having the following:

[0101] The invention is not limited to the embodiments described above, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, claims are attached to disclose the scope of the invention. [Explanation of Symbols]

[0102] 1: Imprint device 7: Control unit 20: Light source unit 1100: Gas detector 1200: Substrate storage space M: Type S: Substrate IM: Imprint material

Claims

1. An imprint method for forming a pattern on an imprint material placed on at least one layer formed on a substrate using a mold, A first step is to acquire gas information regarding the gas in the storage space where the substrate is stored, A second step involves determining the value of a control parameter for controlling exposure to irradiate light onto the imprint material while the imprint material on at least one layer of the substrate stored in the storage space is in contact with the mold, based on the gas information obtained in the first step. A third step involves performing the exposure according to the value of the control parameter determined in the second step, An imprinting method characterized by having the following:

2. The aforementioned exposure is Before curing the imprint material, pre-exposure is performed by irradiating the imprint material with light to increase its viscosity, Following the aforementioned pre-exposure, the main exposure is performed in which light is irradiated onto the imprint material to cure the imprint material, including, The imprinting method according to feature 1.

3. In the second step described above, the values ​​of the control parameters for controlling the pre-exposure are determined, In the third step described above, the pre-exposure is performed. The imprinting method according to feature 2.

4. The imprint method according to claim 3, characterized in that the pre-exposure is performed in parallel with the alignment of the mold and the substrate in the aforementioned state.

5. The imprint method according to claim 1, characterized in that the first step involves obtaining the gas information by detecting the gas using a gas detector placed in the storage space.

6. The imprint method according to claim 1, characterized in that the gas information includes the type of gas and the concentration of the gas.

7. The imprint method according to claim 6, characterized in that the gas contains oxygen.

8. The imprint method according to claim 1, characterized in that the control parameter includes at least one of the illuminance, irradiation time, and wavelength of the light irradiated onto the imprint material.

9. The imprint method according to claim 1, further comprising the step of displaying the gas information acquired in the first step on a user interface.

10. The imprint method according to claim 1, further comprising the step of displaying the value of the control parameter determined in the second step on a user interface.

11. The imprint method according to claim 1, characterized in that the at least one layer includes spin-on carbon.

12. An imprint apparatus that uses a mold to form a pattern on an imprint material placed on at least one layer formed on a substrate, An acquisition unit that acquires gas information regarding the gas in the storage space where the substrate is stored, Based on the gas information acquired by the acquisition unit, a determination unit determines the value of a control parameter for controlling exposure to irradiate light onto the imprint material when the imprint material on at least one layer of the substrate stored in the storage space is in contact with the mold. A processing unit that performs the exposure according to the control parameter value determined by the determination unit, An imprinting device characterized by having [a certain feature].

13. The imprint apparatus according to claim 12, further comprising a user interface for displaying the gas information and the values ​​of the control parameters.

14. The imprint apparatus according to claim 13, characterized in that the user interface accepts user operations to adjust the value of the control parameter.

15. A step of forming a pattern on a substrate using the imprint method described in any one of claims 1 to 11, A step of processing the substrate on which the pattern has been formed in the above step, A process for manufacturing an article from the processed substrate, A method for manufacturing an article, characterized by having the following:

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