Inspection method, imprint device, and manufacturing method of article

Abstract

To provide technique advantageous for inspection of a formation correction part for deforming a mold.SOLUTION: An inspection method for inspecting a formation correction part for deforming a mold that is used for an imprint device, contains: a first step of applying a pressure to a surface on the side opposite to a pattern surface of a mold in a state where the pressure is not applied to the side surface of the mold in which the formation correction part is held by the mold holding part; a second step of applying the pressure to the side surface of the mold by the formation correction part in a state where the pressure is applied to the surface on the side opposite to the pattern surface of the mold; a third step of cancelling a state where the pressure is applied to the surface on the side opposite to the pattern surface of the mold; a fourth step of measuring a deformation amount of the mold in a state where the pressure is applied to the side surface of the mold; a fifth step of repeating the second, third, and fourth steps; and a sixth step of determining the characteristic of the formation correction part on the basis of a deformation characteristic indicating a relation of a pressure value applied to the side surface of the mold by the formation correction part and the deformation amount of the mold that is obtained in the fifth step.SELECTED DRAWING: Figure 4

Description

Technical Field

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

Background Art

[0002] An imprint apparatus forms a pattern on a substrate by curing an imprint material in a state where a mold having a pattern formed thereon is in contact with the imprint material on the substrate, and then separating the mold from the cured imprint material.

[0003] An imprint apparatus generally has a shape correction unit that corrects a relative superposition error (such as magnification) between the mold and the substrate by deforming the mold (its pattern) (see Patent Document 1). In the shape correction unit, a stroke inspection is performed to check whether it has a sufficient correction function. The stroke inspection is preferably performed in a non-contact state where the mold and the substrate are not in contact, for the purpose of omitting the labor and time required for the inspection.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] As a result of the present inventor's intensive study on the stroke inspection, it has been confirmed that even when the shape correction unit is driven by a certain amount, the amount of deformation (shape change amount) of the mold may vary depending on the individual. This is considered to be due to the fact that the flatness of the surface of the mold held by the mold holding unit varies depending on the individual. In such a case, the frictional force acting between the mold and the mold holding unit is different, and even if the shape correction unit applies the same pressure (driving force) to the mold, the amount of deformation of the mold will vary depending on the individual, so that the stroke inspection cannot be accurately performed.

[0006] The present invention has been made in view of such problems of the prior art, and an exemplary object thereof is to provide a technique advantageous for inspecting a shape correction unit that deforms a mold.

Means for Solving the Problems

[0007] In order to achieve the above object, an inspection method according to one aspect of the present invention is an inspection method for inspecting a shape correction unit that applies pressure to a side surface of a mold held by a mold holding unit and deforms the mold, which is used in an imprint apparatus that forms a pattern of an imprint material on a substrate using the mold. The inspection method includes: a first step of applying pressure to a surface opposite to the pattern surface of the mold in a state where the shape correction unit does not apply pressure to the side surface of the mold held by the mold holding unit; a second step of applying pressure to the side surface of the mold by the shape correction unit in a state where pressure is applied to the surface opposite to the pattern surface of the mold; a third step of releasing the state where pressure is applied to the surface opposite to the pattern surface of the mold after the second step; a fourth step of measuring a deformation amount of the mold in a state where pressure is applied to the side surface of the mold by the shape correction unit after the third step; a fifth step of repeating the second step, the third step, and the fourth step so that the deformation amount of the mold is measured for each state where pressure of at least two different pressure values is applied to the side surface of the mold by the shape correction unit; and a sixth step of determining characteristics of the shape correction unit based on a deformation characteristic showing a relationship between a pressure value applied by the shape correction unit to the side surface of the mold and the deformation amount of the mold obtained through the fifth step.

[0008] A further object or another aspect of the present invention will be clarified by embodiments described below with reference to the accompanying drawings.

Effects of the Invention

[0009] According to the present invention, for example, a technique advantageous for inspecting a shape correction unit that deforms a mold can be provided.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0011] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiments, not all of these plurality of features are essential for the invention, and the plurality of features may be arbitrarily combined. Further, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant descriptions are omitted.

[0012] FIG. 1 is a schematic diagram showing the configuration of an imprint device 1 as one aspect of the present invention. The imprint device 1 is a lithography device that is employed in a lithography process, which is a manufacturing process for devices such as semiconductor elements, liquid crystal display elements, and magnetic storage media as articles, and forms a pattern on a substrate. The imprint device 1 brings an uncured imprint material disposed (supplied) on a substrate into contact with a mold, and forms a pattern of a cured product in which the pattern of the mold is transferred by applying energy for curing to the imprint material.

[0013] 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, etc. are 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 light, ultraviolet rays, etc.

[0014] The curable composition is a composition that cures by irradiation with light or by 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, etc.

[0015] The imprint material may be applied in a film form on a substrate by a spin coater or a slit coater. Also, the imprint material may be applied on the substrate in a droplet form or in an island or film form formed by connecting a plurality of droplets by a liquid ejection 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.

[0016] For the substrate, glass, ceramics, metal, semiconductor, resin, etc. are used, and a member made of a material different from the substrate may be formed on its surface as necessary. Specifically, the substrate includes a silicon wafer, a compound semiconductor wafer, quartz glass, etc.

[0017] In this specification and the accompanying drawings, the direction is indicated in an XYZ coordinate system with the direction parallel to the surface on which the substrate is disposed as 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.

[0018] The imprint apparatus 1 performs an imprint process of forming a pattern of the imprint material IM on a substrate using the mold M. The imprint process includes a contact process, an alignment process, a curing process, and a release process. The contact process is a process of bringing the imprint material IM disposed in the shot region (imprint target region) of the substrate S into contact with the pattern region P of the mold M. The alignment process is a process of aligning (aligning) the shot region of the substrate S and the pattern region P of the mold M in a state where the mold M and the substrate S are in contact via the imprint material IM. The curing process is a process of curing the imprint material IM on the substrate in a state where the mold M and the substrate S are in contact via the imprint material IM. The release process is a process of separating the mold M from the cured imprint material IM on the substrate (a process of separating the pattern formed of the cured product of the imprint material IM and the pattern region P of the mold M).

[0019] The imprint apparatus 1 includes a structure ST and an imprint head IH. The imprint head IH drives the mold M in the Z direction in the contact process and the release process. The imprint head IH may have a function of driving the mold M not only in the Z direction but also in the X direction and the Y direction, or may have a tilt function of tilting the mold M in the θX direction and the θY direction.

[0020] The imprint head IH includes a mold holding portion MCK that holds the mold M. The mold holding portion MCK includes a holding surface MCKa that holds the mold M by attracting the outer peripheral region of the back surface Mb of the mold M by a vacuum suction force or an electrostatic force. Note that the back surface Mb of the mold M is the surface on the opposite side of the pattern surface Ma (the surface including the pattern region P) of the mold M.

[0021] Further, the imprint head IH includes a shape correction portion MAG. The shape correction portion MAG has a function of deforming the mold M, specifically, a function of changing the shape of the pattern region P of the mold M in the X direction and the Y direction. The shape correction portion MAG changes the shape of the pattern region P, that is, deforms the pattern region P, for example, by applying pressure (driving force) to the four side surfaces of the mold M.

[0022] The imprint head IH further includes a pressure mechanism BP that applies pressure to the back surface Mb of the mold M. A core out CO may be formed on the back surface Mb of the mold M. The core out CO is formed by digging into the back surface Mb of the mold M (the area of the surface on the opposite side of the pattern area P) in a cylindrical concave shape. The pressure mechanism BP deforms the pattern area P of the mold M into a convex shape toward the substrate S by applying pressure (positive pressure) to the core out CO formed on the back surface Mb of the mold M. Thereby, in the contact process, it becomes possible to bring the center portion of the pattern area P of the mold M into contact with the imprint material IM on the substrate, and the imprint material IM can be efficiently filled into the pattern area P of the mold M.

[0023] Also, when the shape correction unit MAG applies pressure to the mold M to deform the mold M, the pressure mechanism BP may apply pressure to the core out CO formed on the back surface Mb of the mold M. Thereby, the frictional force between the back surface Mb of the mold M and the holding surface MCKa of the mold holding unit MCK is reduced, and the mold M to which pressure is applied from the shape correction unit MAG can be smoothly deformed in the X direction and the Y direction.

[0024] The imprint apparatus 1 has a substrate stage STG supported by a structure ST. The substrate stage STG has a function of driving the substrate S in the X direction, the Y direction, and the θZ direction in order to accurately position the substrate M in the alignment process of aligning the mold M and the substrate S. Also, the substrate stage STG may have a function of driving the substrate S in the θX direction and the θY direction. The substrate stage STG includes a substrate holding unit SCK for sucking and holding the substrate S.

[0025] The imprinting apparatus 1 has a measurement unit AS. In the alignment process, the measurement unit AS detects (observes) the alignment mark MMK for the mold M and the alignment mark SMK for the substrate S, and measures the relative misalignment therebetween, that is, the overlapping errors of both marks in the X and Y directions. The imprinting apparatus 1 may have a plurality of measurement units AS, for example, four or more measurement units AS, in order to measure the overlapping error between the substrates S with high precision. Further, the measurement unit AS may be configured to be drivable in the X and Y directions in order to measure the positions of the alignment marks provided at different locations.

[0026] The imprinting apparatus 1 has an irradiation unit IL. In the curing process, the irradiation unit IL cures the imprinting material IM by irradiating the imprinting material IM with curing light UV in a state where the imprinting material IM disposed on the substrate and the pattern region P of the mold M are in contact with each other. The light UV from the irradiation unit IL may be irradiated onto the imprinting material IM via the mirror ML.

[0027] The imprinting apparatus 1 has a dispenser DSP. The dispenser DSP disposes the imprinting material IM in each shot region of the substrate S. The disposition of the imprinting material IM for each shot region of the substrate S is performed by the dispenser DSP discharging the imprinting material IM in synchronization with the driving of the substrate S while driving the substrate S by the substrate stage STG.

[0028] The imprinting apparatus 1 has a control unit CTL. The control unit CTL comprehensively controls each part of the imprinting apparatus 1 (such as the imprinting head IH, the substrate stage STG, the measurement unit AS, the irradiation unit IL, the dispenser DSP, etc.) according to the program stored in the storage unit, and operates the imprinting apparatus 1. Further, in addition to performing the imprinting process, the control unit CTL performs a process of inspecting the shape correction unit MAG as will be described later. Note that the process of inspecting the shape correction unit MAG is embodied as a stroke inspection in the present embodiment.

[0029] The control unit CTL is configured by, for example, a PLD (abbreviation for Programmable Logic Device) such as an FPGA (abbreviation for Field Programmable Gate Array), or an ASIC (abbreviation for Application Specific Integrated Circuit), or a general-purpose computer (including a CPU and memory) in which a program is incorporated, or a combination of all or part of these. The control unit CTL may be installed inside the imprint device 1, or may be installed at a location separate from the imprint device 1 to remotely control the imprint device 1.

[0030] Next, a stroke inspection for the shape correction unit MAG implemented in the imprint device 1 will be described. The first purpose of the stroke inspection is to inspect (determine) whether the shape correction unit MAG has a sufficient correction function. Further, the second purpose of the stroke inspection is to adjust the drive gain of the shape correction unit MAG for applying pressure to the side surface of the mold M from the shape correction unit MAG.

[0031] FIG. 2 is a diagram showing an example of the configuration of the shape correction unit MAG. As described above, the shape correction unit MAG deforms the pattern region P by applying pressure to the four side surfaces of the mold M. As shown in FIG. 2, the shape correction unit MAG includes a plurality of contact portions MF that contact the side surface of the mold M, and an actuator ACT that drives each of the plurality of contact portions MF in the X direction or the Y direction. The actuator ACT includes, for example, a piezo element or other elements. The components of the shape of the pattern region P that can be controlled by the shape correction unit MAG include, for example, a magnification component, a strain component, a diamond component, a trapezoid component, higher-order components, and the like.

[0032] In this embodiment, the stroke inspection is performed by measuring, with the measuring unit AS, the relative shape deviation (shape deviation amount) between the mold M and the substrate S in the X and Y directions while gradually changing the value of the pressure (pressure value) applied by the shape correction unit MAG to the side surface of the mold M. Since the shape of the substrate S remains constant even when the shape correction unit MAG applies pressure to the side surface of the mold M, the amount of change in the relative shape deviation between the mold M and the substrate S can be regarded as the amount of change in the shape of the mold M, that is, the amount of deformation of the mold M.

[0033] In the stroke inspection, the shape correction unit MAG is inspected by comparing the range (stroke) of the change in the shape of the mold M accompanying the change in the pressure (pressure value) applied by the shape correction unit MAG to the side surface of the mold M with an arbitrary threshold value corresponding to the correction function that the shape correction unit MAG should have. Here, as a characteristic of the shape correction unit MAG, the presence or absence of an abnormality in the shape correction unit MAG is inspected (determined), specifically, whether or not the stroke of the amount of deformation of the mold M, which is the range of the change in the shape of the mold M, is equal to or greater than the threshold value. If the stroke of the amount of deformation of the mold M is equal to or greater than the threshold value, it is determined that there is no abnormality in the shape correction unit MAG. On the other hand, if the stroke of the amount of deformation of the mold M is smaller than the threshold value, there may be an abnormality in the shape correction unit MAG or other units, which serves as a criterion for determining whether to perform a precise inspection.

[0034] Also, in the stroke inspection, the correction function of the shape correction unit MAG is adjusted by reflecting the response characteristics of the change in the shape of the mold M with respect to the change in the pressure applied by the shape correction unit MAG to the side surface of the mold M in the gain (drive gain) of the shape correction unit MAG. Thereby, it becomes possible to always manage (control) the correction function of the shape correction unit MAG in a constant state and to manage so that the shape correction unit MAG has a common correction function in a plurality of imprint apparatuses. Generally, on the premise that the stroke of the amount of deformation of the mold M is equal to or greater than the threshold value, that is, there is no abnormality in the shape correction unit MAG, the gain of the shape correction unit MAG is adjusted (fine-tuned). However, when there is an abnormality in the shape correction unit MAG, the gain of the shape correction unit MAG may be adjusted for the purpose of improving the stroke of the amount of deformation of the mold M.

[0035] The relative shape deviation between the mold M and the substrate S may be measured in a state where the mold M is in contact with the imprint material IM on the substrate. However, since the contact treatment of bringing the mold M into contact with the imprint material IM on the substrate requires labor and time (such as the filling time of the imprint material IM), it is preferable to perform the measurement in a non-contact state where the mold M is not in contact with the imprint material IM on the substrate.

[0036] In the stroke inspection, it was confirmed that the deformation characteristics (the range and response characteristics of the shape change of the mold M with respect to the change in the pressure applied to the side surface of the mold M) showing the relationship between the pressure value applied by the shape correction unit MAG to the side surface of the mold M and the deformation amount of the mold M differ depending on the individual of the mold M. This is considered to be due to the fact that the flatness of the back surface Mb of the mold M held by the mold holding unit MCK differs depending on the individual.

[0037] FIG. 3 is a diagram showing the results of performing a stroke inspection using two different molds M1 and M2. In FIG. 3, the horizontal axis represents the pressure value applied by the shape correction unit MAG to the side surfaces of the molds M1 and M2, and the vertical axis represents the deformation amounts of the molds M1 and M2. Referring to FIG. 3, the deformation amounts (changes) of the molds M1 and M2 with respect to the change in the pressure value applied by the shape correction unit MAG to the molds M1 and M2 are smaller for the mold M2 than for the mold M1. Here, when compared with the threshold value Th corresponding to the correction function that the shape correction unit MAG should have, in the stroke inspection using the mold M1, it is determined that there is no abnormality in the shape correction unit MAG, but in the stroke inspection using the mold M2, it is determined that there is an abnormality in the shape correction unit MAG. Thus, if the determination result of the presence or absence of an abnormality in the shape correction unit MAG changes depending on the individual of the mold M used in the stroke inspection, the stroke inspection cannot be accurately performed.

[0038] Therefore, in the present embodiment, a technique advantageous for inspecting the shape correction unit MAG that enables accurate performance of the stroke inspection on the shape correction unit MAG regardless of the individual of the mold M is provided.

[0039] Referring to FIG. 4, in this embodiment, a stroke inspection for the shape correction unit MAG implemented in the imprint apparatus 1 will be described. FIG. 4 is a flowchart for explaining the stroke inspection in this embodiment.

[0040] In S1, the mold M and the substrate S are carried into the imprint apparatus 1. The mold M carried into the imprint apparatus 1 is held by the mold holding part MCK of the imprint head IH, and the substrate S carried into the imprint apparatus 1 is held by the substrate holding part SCK of the substrate stage STG. Here, in this embodiment, the reason for using not only the mold M to which the shape correction unit MAG to be inspected applies pressure but also the substrate S is to measure the relative shape deviation amount between the mold M and the substrate S.

[0041] In S2, the imprint head IH drives the mold M in the direction in which the distance between the mold M and the substrate S increases (the direction in which the mold M and the substrate S separate), that is, upward. This is to avoid contact between the mold M and the substrate S because when the pressure mechanism BP applies pressure to the back surface Mb of the mold M in S3, the mold M deforms into a convex shape toward the substrate M. In this embodiment, the mold M is driven upward until the distance between the mold M and the substrate S becomes 500 μm or more.

[0042] In S3, the pressure mechanism BP applies pressure (positive pressure) to the back surface Mb of the mold M, specifically, to the core out CO formed on the back surface Mb. Specifically, in a state where the shape correction unit MAG does not apply pressure to the side surface of the mold M held by the mold holding part MCK, pressure is applied to the back surface Mb of the mold M (the first step). Note that the value of the pressure (pressure value) applied by the pressure mechanism BP to the back surface Mb of the mold M in S3 is preferably the same as the value of the pressure applied by the pressure mechanism BP to the back surface Mb of the mold M in the imprint process. Hereinafter, with reference to FIGS. 5(a), 5(b), and 5(c), the effect of applying pressure to the back surface Mb of the mold M by the pressure mechanism BP will be described.

[0043] Fig. 5(a) shows a state where the shape correction part MAG does not apply pressure to the side surface of the mold M. In the suction area VZ of the back surface Mb of the mold M that is sucked (held) by the holding surface MCKa of the mold holding part MCK, the suction force P1 by the mold holding part MCK acts.

[0044] Fig. 5(b) shows, as a comparative example of the present embodiment, a case where the shape correction part MAG applies pressure P2 to the side surface of the mold M in a state where the pressure by the pressure mechanism BP is not applied to the back surface Mb of the mold M. Since the holding surface MCKa of the mold holding part MCK and the suction area VZ of the back surface Mb of the mold M are in contact, a frictional force P3 acts between them according to the pressure P2. Note that since the flatness of the suction area VZ of the back surface Mb of the mold M varies depending on the individual mold M, the frictional force P3 varies for each individual mold M. This means that, as shown in Fig. 3, the pressure that the shape correction part MAG should apply to the side surface of the mold M, which is required to deform the mold M by a certain amount, varies depending on the individual mold M. In such a state, it is not possible to accurately perform a stroke inspection on the shape correction part MAG.

[0045] Figure 3(c) shows, as an example of this embodiment, the case where the shaping correction unit MAG applies pressure P2 to the side surface of the mold M while the pressure P4 applied by the pressure mechanism BP is being applied to the back surface Mb of the mold M (on the side of the core out CO). Since the pressure P4 applied by the pressure mechanism BP acts in the opposite direction to the suction force P1 by the mold holding unit MCK, the total contact pressure acting between the suction area VZ of the back surface Mb of the mold M and the holding surface MCKa of the mold holding unit MCK becomes small. As a result, the frictional force P3 corresponding to the pressure P2 applied by the shaping correction unit MAG to the side surface of the mold M is reduced, and the mold M held by the mold holding unit MCK can be smoothly deformed. Note that by reducing the suction force P1 by the mold holding unit MCK, the same value can be obtained as the total contact pressure acting between the suction area VZ and the holding surface MCKa. However, when the suction area VZ of the mold M and the holding surface MCKa are stuck (ringing), simply reducing the contact pressure may not eliminate the sticking between the suction area VZ and the holding surface MCKa, and there is a possibility that the frictional force P3 is not reduced. Therefore, in this embodiment, the pressure mechanism BP pressurizes in a direction to actively separate the suction area VZ of the mold M from the holding surface MCKa of the mold holding unit MCK, so as to eliminate the sticking between the suction area VZ and the holding surface MCKa.

[0046] The suction force P1 by which the mold holding unit MCK sucks the mold M is generally from 60 kPa to 70 kPa. Therefore, the pressure P4 applied by the pressure mechanism BP to the mold M is preferably from 20 kPa or more to 30 kPa or less. Within such a pressure range, the sticking between the suction area VZ and the holding surface MCKa can be eliminated without the mold M falling from the mold holding unit MCK.

[0047] Regarding the relationship between the suction force P1 with which the mold holding part MCK sucks the mold M and the pressure P4 applied to the mold M by the pressure mechanism BP, considering the area ratio between the suction area VZ and the core out CO, it is advisable to set the pressure P4 to 60% of the pressure value that balances with the suction force P1. Here is a specific numerical example. For instance, when the suction force P1 is -60 kPa and the area ratio between the suction area VZ and the core out CO is 1:1.5, the pressure value (limit value) that balances with the suction force P1 is +40 kPa. Therefore, 24 kPa, which is 60% of such a pressure value, is set as the pressure P4.

[0048] Also, when a core out CO is formed on the back surface Mb of the mold M, since the deformation of the mold M when pressure is applied by the pressure mechanism BP becomes large, the fixation between the adsorption area VZ and the holding surface MCKa is likely to be released. However, even if a core out CO is not formed on the back surface Mb of the mold M, a certain effect can be obtained by applying pressure to the back surface Mb of the mold M.

[0049] In this way, in this embodiment, by applying pressure to the back surface Mb of the mold M, the frictional force P3 can be made sufficiently smaller than the pressure P2 applied to the side surface of the mold M by the shape correction part MAG. Therefore, if the pressure applied to the side surface of the mold M by the shape correction part MAG is constant, regardless of the individual mold M, the deformation amount of the mold M will be constant.

[0050] In S4, with pressure applied to the back surface Mb of the mold M, pressure is applied to the side surface of the mold M by the shape correction part MAG (second step). The shape components of the mold M (pattern area P) to be deformed by the shape correction part MAG applying pressure to the side surface of the mold M can be any of the magnification component, strain component, diamond formation component, trapezoid component, and higher-order components. In this embodiment, the shape correction part MAG applies pressure with at least two different pressure values, preferably 10 or more pressure values, to the side surface of the mold M. However, in S4, the pressure applied by the shape correction part MAG to the side surface of the mold M is only one of all the pressure values (pressure conditions) that should be applied to the side surface of the mold M required for the stroke inspection.

[0051] In S5, after the shape correction unit MAG applies pressure to the side surface of the mold M, the pressure mechanism BP releases the pressure applied to the back surface Mb of the mold M to release the state in which pressure is applied to the back surface Mb of the mold M (third step).

[0052] In S6, the imprint head IH drives the mold M in a direction in which the distance between the mold M and the substrate S decreases (the direction in which the mold M and the substrate S approach each other), that is, downward. This is because in S7, in the proximity state where the mold M and the substrate S are close to each other, the measurement unit AS measures the relative shape deviation between the mold M and the substrate S. As the distance between the mold M and the substrate S decreases, the signal intensities of the marks MMK and SMK detected by the measurement unit M increase, so that the relative shape deviation between the mold M and the substrate S can be measured with high precision. In the present embodiment, in order to measure the relative shape deviation between the mold M and the substrate S with high precision, the mold M is driven downward until the mold M does not contact the imprint material IS on the substrate and the distance between the mold and the substrate becomes 10 μm or less.

[0053] In S7, in a state where the shape correction unit MAG applies pressure to the side surface of the mold M, the measurement unit AS measures the deformation amount of the mold M (fourth step). Specifically, the relative shape deviation between the mold M and the substrate S is measured by detecting a plurality of marks MMK of the mold M and a plurality of marks SMK of the substrate S by a plurality of measurement units AS. From the measurement data thus obtained and the coordinate information of the marks MMK and SMK, the deformation amount (magnification component, diamond component, trapezoid component, etc.) of the mold M is obtained. Here, since the shape of the substrate S is constant and only the shape of the mold M to which pressure is applied by the shape correction unit MAG changes, the change amount of the relative shape deviation between the mold M and the substrate S obtained by the measurement unit AS can be regarded as the change amount of the shape of the mold M, that is, the deformation amount of the mold M. If the measurement accuracy of the deformation amount of the mold M is insufficient, the number of measurements by the measurement unit AS may be increased to improve the measurement accuracy by the averaging effect. The deformation amount of the mold M measured in S7 is stored in the control unit CTL.

[0054] In S8, the shape correction unit MAG determines whether it has applied all the pressure conditions (all the pressure values to be applied to the side surface of the mold M required for the stroke inspection) to the side surface of the mold M. If the shape correction unit MAG has applied all the pressure conditions to the side surface of the mold M, the process proceeds to S9. On the other hand, if the shape correction unit MAG has not applied all the pressure conditions to the side surface of the mold M, the process proceeds to S2 to apply the next pressure condition to the side surface of the mold M. Therefore, until the shape correction unit MAG has applied all the pressure conditions to the side surface of the mold M (until the deformation amount of the mold M has been measured for each state in which at least two different pressure values have been applied to the side surface of the mold M by the shape correction unit MAG), S2 to S7 are repeated (the fifth step).

[0055] In S9, the deformation characteristics are obtained from the deformation amount (shape data) of the mold M obtained through S2 to S8, and based on such deformation characteristics, the characteristics of the shape correction unit MAG, that is, the presence or absence of an abnormality in the shape correction unit MAG are determined (the sixth step). FIGS. 6(a) and 6(b) are diagrams showing an example of the deformation characteristics obtained from the deformation amount of the mold M obtained through S2 to S8, which show the relationship between the pressure value applied by the shape correction unit MAG to the side surface of the mold M and the deformation amount of the mold M, and are plots of the results obtained in S2 to S8. The deformation characteristics shown in FIGS. 6(a) and 6(b) correspond to the response characteristics of the change in the shape of the mold M to the change in the pressure applied by the shape correction unit MAG to the side surface of the mold M. In FIG. 6, the horizontal axis represents the pressure value applied by the shape correction unit MAG to the side surface of the mold M, and the vertical axis represents the deformation amount of the mold M.

[0056] Based on the deformation characteristics shown in FIGS. 6(a) and 6(b), a method for determining the presence or absence of an abnormality in the shape correction unit MAG, specifically, whether the shape correction unit MAG has a sufficient correction function, will be described. For example, in FIG. 6(a), the stroke ST indicates the range of the change in the shape of the mold M accompanying the change in the pressure (pressure value) applied by the shape correction unit MAG to the side surface of the mold M. The shape correction unit MAG is inspected by comparing the stroke ST with the correction function that the shape correction unit MAG should have, that is, the threshold value Th corresponding to the stroke. If the stroke ST is equal to or greater than the threshold value Th, it is determined that there is no abnormality in the shape correction unit MAG. On the other hand, if the stroke of the deformation amount of the mold M is smaller than the threshold value Th, there may be an abnormality in the shape correction unit MAG or other units, which serves as a criterion for determining whether to perform a precise inspection.

[0057] Also, in the present embodiment, the gain of the shape correction unit MAG is also adjusted (seventh step) based on the deformation characteristics showing the relationship between the pressure value applied by the shape correction unit MAG to the side surface of the mold M and the deformation amount of the mold M. For example, it is preferable that the slope SL of the deformation characteristics showing the relationship between the pressure value applied by the shape correction unit MAG to the side surface of the mold M and the deformation amount of the mold M is always constant or common to a plurality of imprint apparatuses. Here, consider the case where a magnification of 1 ppm is input as a correction value for misalignment in the imprint process. If the slope SL of the deformation characteristics is not adjusted, the actual correction amount may be excessive or insufficient with respect to the required correction amount of 1 ppm. Here, let the target value for managing the slope SL of the deformation characteristics be C. When the slope SL of the deformation characteristics deviates from the target value C, a parameter for correcting the deviation, for example, the gain of the shape correction unit MAG, is adjusted. Thereby, the accuracy of the shape correction of the mold M in the imprint process can be maintained constant. As described above, in the present embodiment, the pressure value applied by the pressure mechanism BP to the mold M in the stroke adjustment is used as the pressure value applied by the pressure mechanism BP to the mold M in the imprint process. Therefore, the adjustment result of the gain of the shape correction unit MAG in the stroke inspection is also reflected in the imprint process.

[0058] In the deformation characteristics shown in FIG. 6(a), the stroke ST is equal to or greater than the threshold Th, but the slope SL is smaller than the target value C. Therefore, when the gain of the shape correction unit MAG is adjusted so that the slope SL of the deformation characteristics shown in FIG. 6(a) becomes the target value C, the deformation characteristics shown in FIG. 6(b) are obtained. In the stroke inspection, when the shape correction unit MAG applies pressure to the side surface of the mold M, since the pressure mechanism BP applies pressure to the back surface Mb of the mold M, the influence of the friction of the mold M is reduced. Therefore, the deviation of the slope SL of the deformation characteristics may be regarded as being due to the influence of the gain of the shape correction unit MAG. Also, it may be assumed that the gain of the shape correction unit MAG does not deviate significantly as the stroke ST falls below the threshold Th.

[0059] In S10, the mold M held by the mold holding unit MCK of the imprint head IH and the substrate S held by the substrate holding unit SCK of the substrate stage STG are carried out from the imprint apparatus 1.

[0060] As described above, according to the present embodiment, regardless of the individual of the mold M, the stroke inspection of the shape correction unit MAG can be accurately performed, and the characteristics of the shape correction unit MAG, particularly the presence or absence of an abnormality in the shape correction unit MAG, can be determined. Further, in a state where the frictional force between the back surface Mb of the mold M and the holding surface MCKa of the mold holding unit MCK is reduced, by appropriately adjusting the gain of the shape correction unit MAG, the correction function (behavior) of the shape correction unit MAG can always be managed in a constant state.

[0061] In the present embodiment, on the premise that the characteristics of the mold M are stable (there is no abnormality in the mold M), the characteristics of the shape correction unit MAG are determined based on the deformation characteristics showing the relationship between the pressure value applied by the shape correction unit MAG to the side surface of the mold M and the deformation amount of the mold M. However, the stroke inspection in the present embodiment can also be applied to the determination of the characteristics of the mold M, that is, the presence or absence of an abnormality in the mold M. Specifically, on the premise that the characteristics of the shape correction unit MAG are stable (there is no abnormality in the shape correction unit MAG), it is possible to determine the characteristics of the mold M based on the deformation characteristics showing the relationship between the pressure value applied by the shape correction unit MAG to the side surface of the mold M and the deformation amount of the mold M.

[0062] The pattern of the cured product formed using the imprint apparatus 1 in the present embodiment is used permanently on at least a part of various articles, or temporarily when manufacturing various articles. The articles include electric circuit elements, optical elements, MEMS, recording elements, sensors, or molds, etc. Examples of electric circuit elements include volatile or non-volatile semiconductor memories such as DRAM, SRAM, flash memory, MRAM, and semiconductor elements such as LSI, CCD, image sensors, FPGA, etc. Examples of molds include molds for imprinting.

[0063] The pattern of the cured product is used as it is as a constituent member of at least a part of the above-mentioned articles, or temporarily used as a resist mask. After etching or ion implantation is performed in the substrate processing step, the resist mask is removed.

[0064] Next, a specific manufacturing method of the article will be described. As shown in Fig. 7(a), a substrate such as a silicon wafer with a workpiece such as an insulator formed on its surface is prepared, and then an imprint material is applied to the surface of the workpiece by an inkjet method or the like. Here, the state where the imprint material in the form of a plurality of droplets is applied on the substrate is shown.

[0065] As shown in Fig. 7(b), an imprint mold is opposed with the side on which the concavo-convex pattern is formed facing the imprint material on the substrate. As shown in Fig. 7(c), the substrate with the imprint material applied and the mold are brought into contact with each other and pressure is applied. The imprint material is filled in the gap between the mold and the workpiece. When light is irradiated through the mold as energy for curing in this state, the imprint material cures.

[0066] As shown in FIG. 7(d), after the imprint material is cured and then the mold and the substrate are separated, a pattern of the cured product of the imprint material is formed on the substrate. The pattern of this cured product has a shape in which the concave portion of the mold corresponds to the convex portion of the cured product and the convex portion of the mold corresponds to the concave portion of the cured product. That is, it means that the pattern of the unevenness of the mold has been transferred to the imprint material.

[0067] As shown in FIG. 7(e), when etching is performed using the pattern of the cured product as an etching mask, among the surfaces of the workpiece, the portions where the cured product is absent or remains thinly are removed to form grooves. As shown in FIG. 7(f), when the pattern of the cured product is removed, an article having grooves formed on the surface of the workpiece can be obtained. Here, the pattern of the cured product has been removed, but it may not be removed after processing and may be used, for example, as a film for interlayer insulation included in a semiconductor element or the like, that is, as a constituent member of the article.

[0068] The disclosure of this specification includes the following inspection method, imprint apparatus, and article manufacturing method.

[0069] (Item 1) An inspection method for inspecting a shape correction unit that deforms a mold by applying pressure to a side surface of the mold held by a mold holding unit, which is used in an imprint apparatus for forming a pattern of an imprint material on a substrate using the mold, A first step of applying pressure to a surface opposite to the pattern surface of the mold in a state where the shape correction unit does not apply pressure to the side surface of the mold held by the mold holding unit; A second step of applying pressure to the side surface of the mold by the shape correction unit in a state where pressure is applied to a surface opposite to the pattern surface of the mold; A third step of releasing the state where pressure is applied to a surface opposite to the pattern surface of the mold after the second step; A fourth step of measuring the amount of deformation of the mold in a state where pressure is applied to the side surface of the mold by the shape correction unit after the third step; A fifth step of repeating the second step, the third step, and the fourth step so that the deformation amount of the mold is measured for each state in which the mold side surface is given pressures of at least two different pressure values by the shape correction unit; A sixth step of determining the characteristics of the shape correction unit based on the deformation characteristics showing the relationship between the pressure value applied by the shape correction unit to the side surface of the mold and the deformation amount of the mold obtained through the fifth step; A inspection method characterized by comprising:

[0070] (Item 2) In the sixth step, the inspection method according to item 1, characterized in that the presence or absence of an abnormality of the shape correction unit is determined as the characteristic of the shape correction unit.

[0071] (Item 3) The inspection method according to item 1 or 2, further comprising a seventh step of adjusting a drive gain of the shape correction unit for applying pressure from the shape correction unit to the side surface of the mold based on the deformation characteristics.

[0072] (Item 4) In the seventh step, the inspection method according to item 3, characterized in that the drive gain of the shape correction unit is adjusted so that the slope of the deformation characteristics becomes a target value.

[0073] (Item 5) The inspection method according to any one of items 1 to 4, characterized in that the first step, the second step, the third step, and the fourth step are performed in a state where the mold held by the mold holding unit and the imprint material on the substrate are not in contact with each other.

[0074] (Item 6) The inspection method according to any one of items 1 to 5, characterized in that in the first step, a positive pressure is applied to the surface of the mold opposite to the pattern surface.

[0075] (Item 7) The inspection method according to item 6, wherein the first step is performed with the distance between the mold and the substrate being 500 μm or more.

[0076] (Item 8) The inspection method according to any one of items 1 to 7, wherein in the fourth step, the amount of deformation of the mold is measured by measuring the amount of shape deviation of the mold with respect to the substrate.

[0077] (Item 9) The inspection method according to item 8, wherein the fourth step is performed with the mold and the imprint material on the substrate not in contact and the distance between the mold and the substrate being 10 μm or less.

[0078] (Item 10) An inspection method for inspecting the mold used in an imprint apparatus having a mold holding part for holding the mold and a shape correction part for deforming the mold by applying pressure to the side surface of the mold held by the mold holding part, A first step of applying pressure to the surface of the mold opposite to the pattern surface in a state where the shape correction part is not applying pressure to the side surface of the mold held by the mold holding part; A second step of applying pressure to the side surface of the mold by the shape correction part in a state where pressure is applied to the surface of the mold opposite to the pattern surface; A third step of releasing the state where pressure is applied to the surface of the mold opposite to the pattern surface after the second step; A fourth step of measuring the amount of deformation of the mold in a state where pressure is applied to the side surface of the mold by the shape correction part after the third step; A fifth step of repeating the second step, the third step, and the fourth step such that the amount of deformation of the mold is measured for each state where the shape correction part applies pressures of at least two different pressure values to the side surface of the mold; A sixth step of determining the characteristics of the mold based on the deformation characteristics showing the relationship between the pressure value applied by the shape correction part to the side surface of the mold and the amount of deformation of the mold obtained through the fifth step; An inspection method characterized by having

[0079] (Item 11) An imprint apparatus that forms a pattern of an imprint material on a substrate using a mold, A mold holding part that holds the mold, A shape correction part that deforms the mold by applying pressure to the side surface of the mold held by the mold holding part, A control part that performs a process of inspecting the shape correction part, having The control part, as the process, A first step of applying pressure to the surface of the mold opposite to the pattern surface of the mold in a state where the shape correction part does not apply pressure to the side surface of the mold held by the mold holding part; A second step of applying pressure to the side surface of the mold by the shape correction part in a state where pressure is applied to the surface of the mold opposite to the pattern surface of the mold; A third step of releasing the state where pressure is applied to the surface of the mold opposite to the pattern surface of the mold after the second step; A fourth step of measuring the amount of deformation of the mold in a state where pressure is applied to the side surface of the mold by the shape correction part after the third step; A fifth step of repeating the second step, the third step, and the fourth step so that the amount of deformation of the mold is measured for each state where pressure of at least two different pressure values is applied to the side surface of the mold by the shape correction part; A sixth step of determining the characteristics of the shape correction part based on the deformation characteristics showing the relationship between the pressure value applied by the shape correction part to the side surface of the mold and the amount of deformation of the mold obtained through the fifth step, performing, an imprint apparatus characterized by this.

[0080] (Item 12) A step of forming a pattern on a substrate using the imprint apparatus according to Item 11, A step of processing the substrate on which the pattern is formed in the step, A step of manufacturing an article from the processed substrate, A method for manufacturing an article, characterized by having

[0081] The invention is not limited to the above embodiments, and various changes and modifications are possible without departing from the spirit and scope of the invention. Therefore, claims are appended to disclose the scope of the invention.

Explanation of Reference Signs

[0082] 1: Imprinting device M: Mold S: Substrate MCK: Mold holding part MAG: Shape correction part BP: Pressure mechanism CTL: Control part

Claims

1. An inspection method for inspecting a shape correction unit that deforms a mold by applying pressure to a side surface of the mold held by a mold holding unit, which is used in an imprint apparatus for forming a pattern of an imprint material on a substrate using the mold, comprising: a first step of applying pressure to a surface opposite to the pattern surface of the mold in a state where the shape correction unit does not apply pressure to the side surface of the mold held by the mold holding unit; a second step of applying pressure to the side surface of the mold by the shape correction unit in a state where pressure is applied to the surface opposite to the pattern surface of the mold; a third step of releasing the state where pressure is applied to the surface opposite to the pattern surface of the mold after the second step; a fourth step of measuring a deformation amount of the mold in a state where pressure is applied to the side surface of the mold by the shape correction unit after the third step; a fifth step of repeating the second step, the third step, and the fourth step so that the deformation amount of the mold is measured for each state where the shape correction unit applies pressures of at least two different pressure values to the side surface of the mold; a sixth step of determining characteristics of the shape correction unit based on a deformation characteristic showing a relationship between a pressure value applied by the shape correction unit to the side surface of the mold and the deformation amount of the mold obtained through the fifth step; An inspection method, characterized by comprising the above.

2. In the sixth step, the presence or absence of an abnormality of the shape correction unit is determined as a characteristic of the shape correction unit. The inspection method according to claim 1.

3. The inspection method according to claim 1, further comprising a seventh step of adjusting a drive gain of the shape correction unit for applying pressure to the side surface of the mold from the shape correction unit based on the deformation characteristic.

4. In the seventh step, the drive gain of the shape correction unit is adjusted so that the slope of the deformation characteristic becomes a target value. The inspection method according to claim 3.

5. The first step, the second step, the third step, and the fourth step are performed in a state where the mold held by the mold holding unit and the imprint material on the substrate are not in contact. The inspection method according to claim 1.

6. In the first step, a positive pressure is applied to the surface opposite to the pattern surface of the mold. The inspection method according to claim 1.

7. The inspection method according to claim 6, wherein the first step is performed with the distance between the mold and the substrate being 500 μm or more.

8. The inspection method according to claim 1, wherein in the fourth step, the amount of deformation of the mold is measured by measuring the amount of shape deviation of the mold with respect to the substrate.

9. The inspection method according to claim 8, wherein the fourth step is performed with the mold and the imprint material on the substrate not being in contact and the distance between the mold and the substrate being 10 μm or less.

10. An inspection method for inspecting the mold used in an imprint apparatus having a mold holding part for holding the mold and a shape correction part for deforming the mold by applying pressure to the side surface of the mold held by the mold holding part, a first step of applying pressure to the surface of the mold opposite to the pattern surface in a state where the shape correction part is not applying pressure to the side surface of the mold held by the mold holding part; a second step of applying pressure to the side surface of the mold by the shape correction part in a state where pressure is applied to the surface of the mold opposite to the pattern surface; a third step of releasing the state where pressure is applied to the surface of the mold opposite to the pattern surface after the second step; a fourth step of measuring the amount of deformation of the mold in a state where pressure is applied to the side surface of the mold by the shape correction part after the third step; a fifth step of repeating the second step, the third step, and the fourth step such that the amount of deformation of the mold is measured for each state where the shape correction part applies pressures of at least two different pressure values to the side surface of the mold; a sixth step of determining the characteristics of the mold based on the deformation characteristics showing the relationship between the pressure value applied by the shape correction part to the side surface of the mold and the amount of deformation of the mold obtained through the fifth step; An inspection method, characterized by comprising the above.

11. An imprint apparatus for forming a pattern of an imprint material on a substrate using a mold, a mold holding part for holding the mold; a shape correction part for deforming the mold by applying pressure to the side surface of the mold held by the mold holding part; a control part for performing a process of inspecting the shape correction part; The imprint apparatus has: The control part, as the process, a first step of applying pressure to the surface of the mold opposite to the pattern surface in a state where the shape correction part is not applying pressure to the side surface of the mold held by the mold holding part; A second step of applying pressure to the side surface of the mold by the shape correction unit while applying pressure to the surface opposite to the pattern surface of the mold; A third step of releasing the state of applying pressure to the surface opposite to the pattern surface of the mold after the second step; A fourth step of measuring the deformation amount of the mold in a state where pressure is applied to the side surface of the mold by the shape correction unit after the third step; A fifth step of repeating the second step, the third step, and the fourth step so that the deformation amount of the mold is measured for each state in which pressure of at least two different pressure values is applied to the side surface of the mold by the shape correction unit; A sixth step of determining the characteristics of the shape correction unit based on the deformation characteristics showing the relationship between the pressure value applied by the shape correction unit to the side surface of the mold and the deformation amount of the mold obtained through the fifth step; An imprint apparatus characterized by performing the above.

12. A step of forming a pattern on a substrate using the imprint apparatus according to claim 11; A step of processing the substrate on which the pattern is formed in the above step; A step of manufacturing an article from the processed substrate; A method for manufacturing an article, characterized by comprising the above steps.

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