Planarization apparatus, planarization method, and article manufacturing method

Abstract

To provide an advantageous technique for detecting foreign matter.SOLUTION: A film forming apparatus according to the present invention forms, on a substrate, a film of a curable composition. The film forming device includes: a template holding part that holds a template having an area that contacts the curable composition on the substrate; a substrate holding part that holds the substrate; and detection means that, after a film formation process, detects foreign matter present between the template and the substrate while the template is in contact with the substrate or the curable composition on the substrate, the film formation process including curing the curable composition located on the substrate while the curable composition is in contact with the template, and separating the template and the curable composition from each other to form a film of the curable composition.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a film forming apparatus, a film forming method, and a method for manufacturing an article. [Background technology]

[0002] As the demand for miniaturization of semiconductor devices continues to grow, in addition to conventional photolithography technology, attention is being paid to microfabrication technology, which forms a pattern of curable material on a substrate by molding an uncured curable material on the substrate using a mold and curing it. This technology is called imprint technology, and it is possible to form a fine pattern on the order of several nanometers on the substrate.

[0003] One imprinting technique is the photo-curing method. An imprinting device that uses this method forms a pattern on a substrate by applying a photo-curable material to a shot area on the substrate, shaping the material with a mold, irradiating it with light to harden it, and then separating the mold from the hardened material.

[0004] Recently, a technology for planarizing a curable material on a substrate has been proposed. The technology disclosed in Patent Document 1 aims to improve planarization accuracy by dropping a curable material based on the unevenness of the substrate and curing the dropped curable material while the flat surface of a mold is in contact with the dropped curable material, thereby improving the accuracy of planarization. One of the main performance aspects of a planarization system is minimizing defects and increasing the number of non-defective products. One cause of defects is foreign matter present between the mold and the substrate when they are superimposed. If a foreign matter exists between the mold and the substrate, the curable material at the location where the foreign matter is sandwiched may not contact the flat surface of the mold, resulting in a concave shape due to the foreign matter. This phenomenon results in a defect in a device that planarizes the top surface of a curable material.

[0005] Patent Document 2 discloses a method for detecting whether or not a foreign object is sandwiched between a mold and a substrate from the degree of collapse of interference fringes that spread concentrically over the contact area between the mold and the substrate. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Special Publication No. 2011-529626 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-056589 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the foreign matter detection method of Patent Document 2 requires a wide observation area and high resolution in a system that flattens the entire surface of a substrate at once, and has the problem that it is difficult to detect small foreign matters that are below the resolution limit of the imaging unit (for example, 70 μm) when the mold and substrate are separated by a curable material.

[0008] In addition to foreign matter from inside and outside the equipment that adheres to the substrate during transport, impurities contained in the curable material between the mold and substrate and cured curable material that has peeled off from the substrate can also become foreign matter. When the curable material sandwiched between the mold and substrate is photocured and released, the curable material usually remains on the substrate, but some of the curable material can peel off from the substrate and adhere to the surface of the mold, becoming foreign matter. The thickness of the cured curable material is on the order of tens to hundreds of nanometers, and if such foreign matter, including other small foreign matter of the same size, adheres to the surface of the mold, it continues to be transferred to the substrate, increasing the number of defective products.

[0009] Therefore, an exemplary object of the present invention is to provide an advantageous technique for detecting foreign matter. [Means for solving the problem]

[0010] In order to achieve the above object, one aspect of the present invention provides a film forming apparatus that forms a film of a curable composition on a substrate, the film forming apparatus comprising: a template holding unit that holds a template having an area that comes into contact with the curable composition on the substrate; a substrate holding unit that holds the substrate; and a detection unit that detects foreign matter present between the template and the substrate while the template is in contact with the substrate or the curable composition on the substrate, after a film forming process is performed in which the curable composition on the substrate is cured while in contact with the template and the template and the curable composition are peeled off to form a film of the curable composition. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide an advantageous technique for detecting foreign matter. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a schematic diagram illustrating an example of the configuration of a film forming apparatus according to a first embodiment. [Figure 2] FIG. 1 is a schematic diagram showing a planarization apparatus with a mold in contact with a curable material on a substrate. [Figure 3] 1A and 1B are diagrams illustrating a planarization process in a planarization device. [Figure 4] 10A and 10B are diagrams illustrating an example of a state in which a foreign substance exists between a mold and a substrate. [Figure 5] 1A and 1B are diagrams illustrating an example in which defects occur due to foreign matter during planarization processing. [Figure 6] 3A to 3C are diagrams illustrating foreign object detection according to the first embodiment. [Figure 7] FIG. 4 is a diagram showing an example of a foreign matter detection flow in a planarization process according to the first embodiment. [Figure 8] 10A and 10B are diagrams illustrating foreign object detection according to a second embodiment. [Figure 9] FIG. 10 is a diagram showing an example of a foreign matter detection flow in a planarization process according to the second embodiment. [Figure 10]10A and 10B are diagrams illustrating foreign object detection according to a third embodiment. [Figure 11] FIG. 13 is a diagram showing an example of a foreign matter detection flow in a planarization process according to the fourth embodiment. [Figure 12] 1A to 1C are diagrams for explaining a method for manufacturing an article. DETAILED DESCRIPTION OF THE INVENTION

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. First Embodiment FIG. 1 is a schematic diagram showing the configuration of a film forming apparatus according to a first embodiment. In the specification and drawings, directions are indicated in an XYZ coordinate system, with the horizontal plane being the XY plane. Generally, a substrate 3, which is the object to be processed, is placed on a substrate holder so that its surface is parallel to the horizontal plane (XY plane). Therefore, in the following, the directions perpendicular to each other in a plane along the surface of the substrate 3 are referred to as the X-axis and Y-axis, and the direction perpendicular to the X-axis and Y-axis is referred to as the Z-axis. Furthermore, in the following, the directions parallel to the X-axis, Y-axis, and Z-axis in the XYZ coordinate system are referred to as the X-direction, Y-direction, and Z-direction, respectively, and the directions of rotation around the X-axis, Y-axis, and Z-axis are referred to as the θX-direction, θY-direction, and θZ-direction, respectively.

[0014] In this embodiment, a planarization apparatus 1 is used as the film forming apparatus. The planarization apparatus 1 is an apparatus that uses a template 2 (also called a mold or superstrate) to planarize a curable material on a substrate 3. The planarization apparatus 1 hardens the curable material on the substrate while the curable material is in contact with the template 2, and then separates the hardened curable material from the template 2 to form a globally or locally flat surface (planarized film) of the curable material on the substrate.

[0015] The template 2 has a flat surface for contacting the curable material on the substrate and is a member (film-forming member) for shaping the curable material to conform to the contact surface by contacting the flat surface with the curable material. A mold made of a light-transmitting material is preferably used as the template 2, taking into consideration the light irradiation process. Specific examples of materials for the template 2 include glass, quartz, optically transparent resins such as PMMA (Polymethyl methacrylate) and polycarbonate resin, transparent metal deposition films, flexible films such as polydimethylsiloxane, photocurable films, and metal films. The template 2 is preferably the same size as or larger than the substrate. For example, a circular shape with a diameter greater than 300 mm and less than 500 mm is preferred, but is not limited thereto. The thickness of the template 2 is preferably greater than 0.25 mm and less than 2 mm, but is not limited thereto.

[0016] The curable material may be, for example, a curable composition that cures upon irradiation with light, such as a UV-curable liquid. Typical examples of UV-curable liquids include monomers such as acrylates and methacrylates. The curable material may also be referred to as a curable composition or a formable material. The curable material may contain any of a polymerizable compound, a photopolymerization initiator, a non-polymerizable compound, and a solvent. The non-polymerizable compound may include at least one of a sensitizer, a hydrogen donor, an internal mold release agent, a surfactant, an antioxidant, and a polymer component. The curable material of this embodiment cures upon irradiation with light (ultraviolet rays) having a wavelength of 200 to 380 nm, for example. It cures upon irradiation with ultraviolet rays. However, this is not limited to this, and the curable material may also be cured by electromagnetic waves other than ultraviolet rays.

[0017] The planarization apparatus 1 includes a chuck 4 that holds the substrate 3, a substrate stage 6 that holds the chuck 4 and can be driven in the X and Y directions, and a base 12 that supports the substrate stage 6 and serves as the foundation of the planarization apparatus 1. The planarization apparatus 1 also includes an upper portion, in other words, a contact module 5 (template holding unit, mold holding unit, imprint head) that holds the template 2 at a position that allows it to face the substrate 3 held by the chuck 4 and has a drive unit that moves up and down in the Z direction. The planarization apparatus 1 also includes an imaging unit 7 that can capture images of the template 2 and substrate 3 above the contact module 5. The contact module 5 and imaging unit 7 are supported by a top base 11. The top base 11 also supports a measurement sensor 8 that can measure the template 2 and substrate 3, a curing module 9 that can harden the curable material, and an applicator 10 (supply unit) that applies (supplies) the curable material to the substrate 3. The planarization apparatus 1 also includes a control unit 13 that controls the operation of the planarization apparatus 1.

[0018] The substrate 3 is carried in from outside the planarization apparatus 1 by a substrate carrying unit (not shown) including a carrying hand (not shown). After the substrate stage 6 is moved to a substrate carrying-in location within the plane of the base 12, the substrate 3 is handed over from the carrying hand and held by the chuck 4.

[0019] The substrate stage can be driven in at least one axis, either the X or Y axis, and has a drive stroke sufficient to pass under the unit supported by the top base 11. The substrate stage preferably has a drive unit capable of driving in two axes, X and Y. Furthermore, the substrate stage 6 preferably has drive in the Z-axis rotation direction, since this enables rotational alignment between the template 2 and the substrate 3 to be performed when necessary. Examples of drive mechanisms within the substrate stage 6 include an actuator such as a linear motor that powers the moving unit, including the chuck 4, an encoder that detects position on the nanometer scale, and an air guide that levitates the substrate stage 6 several micrometers above the base 12. The chuck 4 adsorbs and holds the substrate 3 by vacuum or electrostatic adsorption. The chuck 4 and substrate stage 6 function as a substrate holder.

[0020] The contact module 5 includes an actuator, such as a linear motor or air cylinder, as a drive unit for moving up and down in the Z direction. The contact module 5 can be shifted in the Z direction and can also be driven to tilt the template 2. The contact module 5 may also include an encoder for determining its position and multiple force detection sensors. The contact module 5 may include a space separated by a light-transmitting member (e.g., a quartz plate) and the template 2, and the pressure within the space can be adjusted to deform the template 2 during contact and separation. The contact module 5 may include a mechanism for increasing air pressure on the surface supporting the template 2 so that, when the template 2 is brought into contact with the curable material on the substrate 3, contact begins at the center of the template 2 and progresses toward the periphery of the template 2. In this embodiment, the contact module 5 uses a vacuum suction method to hold the template 2. However, a leaf spring or electrostatic suction method may also be used to support the template 2.

[0021] The imaging unit 7 has an optical system and an imaging system for observing the contact area between the template 2 and the curable material on the substrate 3. The imaging unit 7 can observe the state of the curable material spreading on the substrate 3, and based on the observation results, the supply amount and application pattern of the curable material can be optimized. The imaging unit 7 also captures an image of the interference color generated by the light reflected from the template 2 and the light reflected from the substrate 3.

[0022] The measurement sensor 8 is a sensor capable of measuring the distance to the upper surface of the transparent template 2, i.e., the surface opposite the surface in contact with the curable material. The measurement sensor 8 can also measure the distance to the surface of the substrate 3 regardless of whether or not it is in contact with the template 2. Examples of the measurement sensor 8 include a distance sensor with a white LED light source, and a distance sensor that emits multicolor light, which can achieve stable, high-intensity emission over a wider wavelength range than a white LED light source and can measure with higher accuracy over a wider range than a white LED. The measurement sensor 8 of this embodiment, for example, has a measurement spot diameter of several μm to several hundred μm, a measurement resolution of several nm, and a measurement reproducibility of several nm. Because such distance sensors have a relatively small measurement spot diameter, they can accurately measure even smaller irregularities.

[0023] As mentioned above, the measurement spot diameter of the measurement sensor 8 is relatively small, so in order to measure the entire area of ​​the substrate 3, the entire surface of the substrate 3 is measured by the measurement sensor 8 while the substrate stage 6 is scanned. It is also possible to measure the surface of the substrate 3 locally as a means of shortening the time required to measure the entire area of ​​the substrate 3.

[0024] For example, if the curable material is a material that is cured by light, the curing module 9 has at least one light source that generates light of a wavelength that cures the curable material and irradiates the light toward the curable material formed by the template 2. This causes the curable material to be cured according to the shape of the template 2. The light source may be a UV lamp, a UV LED, or the like. For example, if the curable material is a material that is cured by heat, the curing module 9 may have a heat source such as a heater. Note that the curing module 9 may be a unit that has both a light source and a heat source.

[0025] The applicator 10 has multiple nozzles, which dispense the curable material toward the substrate 3. The nozzle diameters range from several microns to several tens of microns, and the multiple nozzles within the applicator 10 dispense the curable material onto the substrate 3 in droplets of picoliter order or larger. The droplet size and droplet position (arrangement) can be changed. For example, by adjusting the droplet density distribution, the thickness of the curable material sandwiched between the template 2 and the substrate 3 can be intentionally changed within the surface. By making such adjustments, even if there are pattern steps on the substrate surface, the surface can be made flat by contacting the template 2. The thickness of the curable material sandwiched between the template 2 and the substrate 3 can also be set arbitrarily. Note that if a substrate 3 already supplied with curable material is loaded into the planarization apparatus 1 by a substrate transport unit, the applicator 10 does not need to be configured as part of the planarization apparatus 1. In other words, an external device may be used as the applicator 10.

[0026] The control unit 13 controls the operation of each unit of the planarization apparatus 1. Specifically, the control unit 13 controls, for example, the driving of the substrate stage 6 and the contact module 5, the imaging operation of the imaging unit 7, the measurement operation of the measurement sensor 8, and the coating operation of the coater 10. The control unit 13 can be configured, for example, by a computer having a processor such as a CPU (Central Processing Unit) and a storage unit such as a memory. The control unit 13 may also be configured, for example, by a PLD (Programmable Logic Device) such as an FPGA (Field Programmable Gate Array), an ASIC (Application Specific Integrated Circuit), a general-purpose computer with an embedded program, or a combination of all or part of these.

[0027] FIG. 2 is a schematic diagram showing the planarization apparatus 1 in contact with the template 2 and the curable material on the substrate 3. The substrate stage 6 is driven to move the substrate 3 directly below the template 2, and then the contact module 5 moves the template 2 closer to the substrate 3. At this time, the substrate 3 may be moved closer to the template 2 by driving the substrate 3, or both the template 2 and the substrate 3 may be driven to move the template 2 closer to the substrate 3. As the template 2 and the substrate 3 move closer to each other, air pressure is applied to the side of the template 2 opposite the surface that will come into contact with the curable material on the substrate 3. This causes the template 2 to assume a downward convex shape toward the substrate 3. The template 2 is then moved closer to the substrate 3 with the central portion of the template 2 closest to the substrate 3, and the template 2 and the curable material on the substrate 3 come into contact from the center. After contact begins, the contact module 5 continues to move the template 2 closer to the substrate 3, gradually reducing the air pressure as the template 2 and the substrate 3 come into contact. As a result, the template 2 comes into contact with the curable material on the substrate 3 in a concentric pattern, and when it reaches the edge of the substrate, the downward movement of the contact module 5 stops and the air pressure becomes zero. After the force detection sensor confirms that the template 2 is placed on the substrate surface, the contact module 5 stops air suction to the template 2 and retracts upward. This action releases the template 2 from the contact module 5, and the flat surface of the template 2 comes into complete contact with the curable material on the substrate 3, resulting in a state in which the flat surface of the template 2 conforms to the surface shape of the substrate 3 (contact state).

[0028] Next, an overview of the flow of the film formation process in this embodiment will be described. Fig. 3 is a diagram illustrating the planarization process in the planarization apparatus 1. Here, a process is described in which a curable material is dropped onto the entire surface of the substrate, and the curable material is brought into contact with the template 2 to planarize the curable material. However, the curable material on a partial region of the substrate 3 may also be brought into contact with the template 2 to planarize the curable material.

[0029] First, as shown in Fig. 3(A), a curable material 20 is supplied or placed by an applicator 10 onto a substrate 3 having a base pattern 3a. Fig. 3(A) shows a state before the curable material 20 is supplied onto the substrate 3 and the template 2 (the flat surface 2a thereof) is brought into contact with the curable material 20. Next, the substrate 3 is transported by a substrate stage 6 from below the applicator 10 to below the contact module 5.

[0030] Next, as shown in Figure 3(B), the distance between the substrate 3 and the template 2 is adjusted by the drive unit of the contact module 5 so that the curable material 20 on the substrate 3 comes into contact with the (flat surface 2a of the) template 2 (contact step). Figure 3(B) shows a state in which the template 2 has been released from the contact module 5, and the flat surface 2a of the template 2 is in complete contact with the curable material 20 on the substrate 3, and the flat surface 2a of the template 2 follows the surface shape of the substrate 3.

[0031] 3(B), the substrate stage 6 is driven to a curing position below the curing module 9. There, the light source of the curing module 9 irradiates the curable material 20 on the substrate with curing energy via the template 2, thereby curing the curable material 20 (curing step).

[0032] Next, the substrate stage 6 is driven to a position below the contact module 5, and the contact module 5 adjusts the distance between the substrate 3 and the template 2 so that the template 2 is separated from the cured curable material 20 on the substrate 3. Specifically, after the substrate stage 6 returns to below the contact module 5, the contact module 5 descends, and while checking the Z-direction position and force detection, air-sucks the template 2 again, raises the template 2, and peels it off from the substrate 3 (demolding process). The substrate 3 side is coated with a coating that prevents the curable material from peeling off, while the template 2 is coated with a coating that makes it easy to peel off the curable material. Furthermore, because peeling (demolding) the template 2 and substrate 3 requires a force of several tens to several hundreds of newtons, an assist mechanism (not shown) is also provided from the substrate stage. During demolding, the assist mechanism pushes the template 2 from the substrate stage 6 side without directly touching the substrate 3, thereby peeling it off.

[0033] This allows a layer of the curable material (planarizing layer) having a uniform thickness to be formed over the entire area of ​​the substrate 3. For convenience, the cured curable material will be referred to as the curable material 21. Fig. 3(C) shows a state in which a planarizing layer made of the cured product of the curable material has been formed on the substrate 3.

[0034] In such a planarization process, if a foreign object is present between the template 2 and the substrate 3, defects may occur. FIG. 4 is a diagram illustrating an example of a state in which a foreign object is present between the template 2 and the substrate 3. Specifically, this diagram illustrates a state in which the template 2 and the substrate 3 are in contact with each other via the curable material 20, with a foreign object 30 also sandwiched between them. As described above, the thickness of the curable material 20 at the time of contact is in the range of several tens of nanometers to several hundreds of nanometers, and the foreign object 30 is, for example, on the order of micrometers or a huge foreign object on the order of 100 micrometers.

[0035] If the foreign object 30 is larger than a predetermined size, it can be detected by checking it with the imaging unit 7 in the contact step. Specifically, with the flat surface 2a of the template 2 following the surface shape of the substrate 3, the imaging unit 7 measures interference fringes caused by contact between the template 2 and the substrate 3, thereby making it possible to check for foreign object 30 present between the template 2 and the substrate 3. However, if the foreign object 30 is smaller than the resolution of the imaging unit 7, it may not be detected by foreign object detection using the imaging unit 7.

[0036] Measurement by the measurement sensor 8 can detect foreign matter larger than the thickness of the curable material 20, specifically, for example, several times the thickness of the curable material 20. For foreign matter detection by the measurement sensor 8, for example, a clean (neat) substrate 3 without any foreign matter is measured by the measurement sensor 8, and a clean (neat) template 2, such as after cleaning, is placed in contact with the clean substrate 3, and the resulting measurement is used as a reference (standard). Subsequent measurements are made on the substrate used in the planarization process in the media production process and on the substrate itself when checking the quality of the planarization device 1, and multiple local measurements are made even when the substrate and template are in contact. Local changes can also be measured by comparing the measurement results with the reference. Furthermore, the differences between the undulations, warping, and steps of the comparison substrate alone and the clean substrate 3, as well as the differences when the comparison substrate is in contact with the template 2, can be confirmed. By confirming the difference between these differences, information on the presence or absence of foreign matter, its location, and its size can be obtained.

[0037] When checking the difference, the distance between the substrate to be measured and the measurement sensor 8 changes, for example, due to temperature changes inside the device, as the relative position of the top base 11 and base 12 changes, and the value of the measurement sensor 8 changes, so the change in value over the entire measurement surface is approximated to the first order and used as the difference from the reference. When checking the difference, check the local changes within the substrate surface, and if necessary, re-measure areas that appear to have changed based on the difference results.

[0038] However, the meniscus force of the liquid hardenable material 20 applies a force in a direction to crush the foreign matter, so the foreign matter tends to become smaller than the thickness of the hardenable material 20. If the foreign matter is smaller than the thickness of the hardenable material 20, the measurement sensor 8 may not be able to detect the foreign matter.

[0039] FIG. 5 illustrates an example of defects caused by foreign matter during a planarization process. This figure shows the state after the curable material 21 has been cured in the curing module 9 and released from the mold. After release, the curable material 21 remains on the substrate 3, but foreign matter 30 or pieces of curable material 31 may adhere to the template 2 during the demolding process. The area of ​​the pieces of curable material 31 ranges from the sub-micron order to the millimeter order, and their thickness corresponds to the height of the curable material 21. The foreign matter 30 or pieces of curable material 31 can create recessed shapes 22a and 22b in the curable material 21, resulting in defects and adversely affecting the planarization of the substrate. Furthermore, the foreign matter 30 or pieces of curable material 31 attached to the template 2 can also cause recessed defects on other substrates 3 during a subsequent planarization process. The foreign matter 30 or pieces of curable material 31 attached to the template 2 can cause defects on the substrate 3 unless they are peeled off from the template 2. This can result in defects on multiple substrates 3. In this specification, the term "foreign matter" includes particles and pieces of hardenable material 31.

[0040] FIG. 6 is a diagram illustrating foreign object detection according to the first embodiment. This figure shows the state in which the substrate stage 6 has been moved from the state shown in FIG. 5 and the template 2 has been placed on the substrate 3 again. The movement of the substrate stage 6 is a horizontal (XY) shift or rotational movement, and the amount of movement can be on the order of microns to several millimeters. The substrate 3 and the template 2 are displaced relative to each other in the horizontal direction; in other words, the relative horizontal positions of the substrate 3 and the template 2 are changed. This movement allows the positions of the recessed shapes 22a and 22b, which are defects in the curable material 21 caused by the foreign object 30 or the hardenable material piece 31, to be shifted from each other. In the state shown in FIG. 6, the hardenable material 21 is solid after curing, and no meniscus force acts on it. Therefore, the deformation of the template 2 due to the foreign object 30 or the hardenable material piece 31 is greater than when the liquid hardenable material 20 is present between the template 2 and the template 2, thereby improving the resolution of foreign object detection by the imaging unit 7. Therefore, even foreign objects as small as 100 nm can be detected by the imaging unit 7. Furthermore, detection by the measurement sensor 8 becomes easier because the deformation of the template 2 becomes large.

[0041] In the foreign object detection of this embodiment, either the imaging unit 7 or the measurement sensor 8 may be used as the detection means. Furthermore, after the position of the foreign object is confirmed based on the image from the imaging unit 7, the position where the foreign object is confirmed may be measured by the measurement sensor 8 to identify the size of the foreign object. In this case, it is possible to reduce the number of measurement points by the measurement sensor 8.

[0042] 7 is a diagram showing an example of a foreign substance detection flow in the planarization process according to the first embodiment. Each operation (step) shown in this flowchart can be executed under the control of the control unit 13.

[0043] After the substrate 3 is carried into the planarization apparatus 1, the applicator 10 applies (supplies) the curable material 20 to the entire surface of the substrate 3 (S110). Thereafter, the substrate stage 6 moves the substrate from below the applicator 10 to below the contact module 5, and the contact module 5 is lowered to bring the curable material 20 on the substrate 3 into contact with the (flat surface of) the template 2 (S111).

[0044] The template 2 and the substrate 3 begin to come into contact from the center, and the template 2 is released from the contact module 5. The substrate 3 and the template 2 come into contact over the entire area via the curable material 20, completing filling (S112). Then, while supporting the template 2 released from the contact module 5, the substrate stage 6 is moved to below the curing module 9, and the curable material 20 is cured by irradiating it with curing energy from the curing module 9 (S113). After curing, the substrate stage 6 is moved below the contact module 5, and the template 2 is held by the contact module 5, and the curable material 21 on the template 2 and the substrate 3 is peeled off (S114). This series of processes from S110 to S114 is called a planarization process (forming process).

[0045] After the planarization process is completed, the substrate stage 6 is moved slightly in the horizontal direction (X and Y directions) to change the horizontal relative position between the template 2 and the substrate 3 (S115). If the contact module 5 can be driven in the horizontal direction (X and Y directions), the contact module 5, or both the substrate stage 6 and the contact module 5, may be driven to change the horizontal relative position between the template 2 and the substrate 3.

[0046] Thereafter, the template 2 is placed on the substrate 3 again (S116). In other words, the contact step is performed again. The state of S116 is a state in which the template 2 is held by the contact module 5. In this state, an image is acquired by the imaging unit 7, or the template 2 is detached from the contact module 5 and then an image is acquired by the imaging unit 7, or the measurement sensor 8 measures the difference in height within the plane of the template 2 (S117).

[0047] Based on the image acquired by the imaging unit 7 or the measurement results of the measurement sensor 8, the control unit 13 determines whether a foreign object has been detected (S118). That is, the control unit 13 acquires information on the presence or absence of a foreign object based on the image acquired by the imaging unit 7 or the measurement results of the measurement sensor 8. Specifically, if a change characteristic of a foreign object is observed in the image acquired by the imaging unit 7, such as interference fringes remaining after filling, or if a protrusion is confirmed from an approximate plane of the in-plane height in the measurement results of the measurement sensor 8, the control unit 13 determines that a foreign object is present (a foreign object has been detected) (Yes). If it is determined that a foreign object is present, the control unit 13 calculates the foreign object's position and size within the surface of the template 2 to acquire information on the foreign object's position and size (S119). Thereafter, the template 2 is cleaned by removing the template 2 from the apparatus and cleaning it, or by removing the foreign object from the surface of the template 2 using an adhesive substrate within the apparatus, or by removing the foreign object using air blowing or air vacuuming. Note that the cleaning method is not limited to these. By calculating the size and position of the foreign matter, it is possible to perform local cleaning based on the calculated position and size of the foreign matter. This reduces the time required for cleaning. Note that cleaning outside the apparatus takes time, so instead of cleaning outside the apparatus, the template may be replaced (S120).

[0048] Although an example of detecting foreign matter within the planarization process has been described here, foreign matter detection (S115 to S118, detection process) may be performed, for example, at a predetermined cycle, or when an abnormality such as a defect occurs during the planarization process. Foreign matter detection may also be performed during the process of checking the quality of the planarization device 1. When foreign matter detection is performed during the process of checking the quality of the planarization device 1, the planarization process is performed at least once before foreign matter detection is performed during the process of checking the quality of the planarization device 1.

[0049] As described above, according to this embodiment, even if the foreign matter present between the template 2 and the substrate 3 is relatively small, it is possible to detect the foreign matter.

[0050] Second Embodiment Next, a second embodiment will be described using FIGS. 8 and 9 . Note that the same or similar components or steps as those in the above-described embodiment are denoted by the same reference numerals, and redundant description will be omitted. FIG. 8 is a diagram illustrating foreign matter detection according to the second embodiment. Here, after the planarization process, the template 2 and the curable material 21 on the substrate 3 are not brought into direct contact with each other, but are brought into contact via the liquid curable material. Specifically, FIG. 8 shows a state in which the substrate stage 6 is moved from the state shown in FIG. 5 , and the applicator 10 applies the curable material 40 onto the planarization layer (curable material 21) formed on the substrate 3, bringing the template 2 and the liquid curable material 40 on the substrate 3 into contact with each other. The curable material 40 has a thickness thinner than the cured curable material 21. For example, when the cured curable material 21 is 100 nm thick, the curable material 40 has a thickness of approximately 30 nm, which is preferably less than half the thickness of the cured curable material 21.

[0051] The height of the pieces of curable material 31 generated when the cured curable material 21 is released from the template can be considered to be the same as that of the cured curable material 21, and is, for example, 100 nm. By making the thickness of the curable material 40 thinner than that of the curable material 21, it becomes possible to confirm the protrusions caused by the pieces of curable material 31. Furthermore, when the contact step is performed again, it is desirable to shift the overlapping position slightly from that in the initial contact step, as in FIG. 6. When the template 2 and the substrate 3 are in contact with each other via the uncured curable material 40, the amount of unevenness is reduced by the meniscus force described above, so it is desirable to measure the top surface of the template 2 with a measurement sensor 8 that can measure with high accuracy.

[0052] 9 is a diagram showing an example of a foreign substance detection flow in a planarization process according to the second embodiment. Each operation (step) shown in this flowchart can be executed under the control of the control unit 13. S110 to S114 in this embodiment are the same as S110 to S114 in FIG. 7 of the first embodiment, and therefore a description thereof will be omitted.

[0053] In this embodiment, after the demolding in S114, a smaller amount of curable material than that in S110 is applied to the same substrate 3, i.e., the substrate 3 on which the planarization layer has been formed (S315). In other words, the curable material is applied to a thickness thinner than that in S110. Then, contacting (S316) and filling (S317) are performed again. Here, S316 and S317 are the same steps as S111 and S112, and therefore their explanation will be omitted. Then, steps similar to S117 to S120 in FIG. 7 of the first embodiment are performed.

[0054] As described above, according to this embodiment, the template 2 is brought into contact with the uncured curable material 40, and therefore damage to the template 2 can be reduced.

[0055] Third Embodiment Next, a third embodiment will be described using FIG. 10 . Components identical or similar to those in the above-described embodiments are designated by the same reference numerals, and redundant description will be omitted. FIG. 10 is a diagram illustrating foreign matter detection according to the third embodiment. Specifically, this figure shows the state in which the substrate 3 in FIG. 5 is replaced with another clean substrate 43, the applicator 10 applies a curable material 40 to the substrate 43, and then the template 2 and the curable material 40 on the substrate 43 are brought into contact. As in FIG. 8 of the second embodiment, the curable material 40 is applied to a thickness thinner than the curable material 21 hardened during the planarization process of the substrate 3. In this embodiment, to detect the curable material pieces 31, a measurement sensor 8 is used to measure multiple locations on the surface of the substrate 43, and the position and size of the foreign matter are identified based on the unevenness within the substrate surface.

[0056] The foreign matter detection flow of this embodiment is similar to that of the second embodiment, so only the differences will be described. In this embodiment, after S114 and before S315, a substrate 43 different from substrate 3 is carried into the device. Then, from S315 onwards, processing is carried out using substrate 43. Note that substrate 43 may also be an inspection substrate.

[0057] According to this embodiment, the template 2 and the substrate 43 are not brought into direct contact with each other, but are brought into contact with each other via the curable material 40 on the substrate 43, thereby reducing damage to the template 2 or the substrate 43 due to direct contact between the template 2 and the substrate 43.

[0058] In this embodiment, step S315 may be omitted. That is, the template 2 may be brought into direct contact with the substrate 43. In this case, the deformation of the template 2 caused by a foreign object becomes larger, so that even smaller foreign objects can be easily detected.

[0059] <Fourth embodiment> Next, a fourth embodiment will be described with reference to FIG. 11. The same or similar configurations or steps as those in the above-described embodiments are denoted by the same reference numerals, and duplicated descriptions will be omitted. FIG. 11 is a diagram showing an example of a foreign matter detection flow in a planarization process according to the fourth embodiment. Each operation (step) shown in this flowchart can be executed under the control of the control unit 13. S110 to S119 in this embodiment are the same steps as those in FIG. 7 of the first embodiment.

[0060] In this embodiment, in S220, cleaning of the template 2 is performed inside the apparatus. Thereafter, the template 2 is placed again on the substrate 3 that was once released, and foreign matter detection is performed. Specifically, when the location of the foreign matter attached to the template 2 can be identified, the foreign matter is locally removed using, for example, an air vacuum nozzle (not shown) provided on the substrate stage 6, and then foreign matter detection (S115 to S118) is performed again.

[0061] In this embodiment, the template 2 can be checked immediately after cleaning, reducing downtime, and running costs can be reduced by continuing to use the template 2 without replacing it.

[0062] The substrate stage 6 can then be moved under the measurement sensor 8 and curing module 9 with the template 2 still on it, allowing the unevenness of the top surface of the template 2 to be measured and the curable material between the template 2 and the substrate 3 to be cured.

[0063] <Embodiments of Imprint Apparatus> The above-described embodiment can also be applied to an imprinting apparatus that performs an imprinting process in which an imprinting material, which is a composition on a substrate, is brought into contact with a template (also called a mold) having a concave-convex pattern, thereby transferring the pattern of the template to the imprinting material. The flow of the imprinting process (forming step) is the same as S110 to S114 in Fig. 7, but in the case of the imprinting process, it is necessary to align the template and the substrate before the contacting step (S111).

[0064] When the above-described embodiment is applied to an imprint apparatus, a pattern of a curable material may be formed on the substrate, but in this case, it is necessary to obtain pattern information and acquire changes in the unevenness of the template 2 due to steps in the pattern. This allows the control unit 13 to determine whether the changes in the unevenness of the template 2 are due to steps in the substrate or foreign matter.

[0065] <Embodiment of an article manufacturing method> The pattern of the cured product formed using the imprinting apparatus is used permanently on at least a portion of various articles, or temporarily when manufacturing various articles. Examples of articles include electrical circuit elements, optical elements, MEMS, recording elements, sensors, and templates (molds). Examples of electrical circuit elements include volatile or nonvolatile semiconductor memories such as DRAM, SRAM, flash memory, and MRAM, and semiconductor elements such as LSI, CCD, image sensors, and FPGA. Examples of templates include molds for imprinting.

[0066] The pattern of the cured product may be used as it is as at least a part of a component of the article, or may be used temporarily as a resist mask, which is removed after etching or ion implantation in a substrate processing step.

[0067] Next, a specific method for manufacturing an article will be described. Fig. 12 is a diagram for explaining the method for manufacturing an article. As shown in Fig. 12(A), a substrate 3z such as a silicon wafer having a workpiece 2z such as an insulator formed on its surface is prepared, and then an imprint material 3z is applied to the surface of the workpiece 2z by an inkjet method or the like. Here, a state in which multiple droplets of the imprint material 3z have been applied to the substrate is shown.

[0068] As shown in Figure 12(B), the imprint template 4z is placed with the side on which the concave-convex pattern is formed facing the imprint material 3z on the substrate. As shown in Figure 12(C), the substrate 3z to which the imprint material 3z has been applied is brought into contact with the template 4z, and pressure is applied. The imprint material 3z fills the gap between the template 4z and the workpiece 2z. In this state, when light is irradiated through the template 4z as hardening energy, the imprint material 3z hardens.

[0069] 12(D), after the imprint material 3z is cured, the template 4z and the substrate 3z are separated, forming a pattern of the cured imprint material 3z on the substrate 3z. In this cured material pattern, the recesses of the template correspond to the protrusions of the cured material, and the protrusions of the template correspond to the recesses of the cured material, i.e., the recess-protrusion pattern of the template 4z is transferred to the imprint material 3z.

[0070] As shown in Figure 12(E), when etching is performed using the cured material pattern as an etching-resistant mask, portions of the surface of the workpiece 2z where no cured material or only a thin layer remains are removed, forming grooves 5z. As shown in Figure 12(F), when the cured material pattern is removed, an article is obtained in which grooves 5z are formed in the surface of the workpiece 2z. Here, the cured material pattern is removed, but it may also be used as an interlayer insulating film included in a semiconductor device or the like, i.e., a component of an article, without being removed after processing.

[0071] Although the example has been described in which a template for transferring a circuit pattern provided with a concave-convex pattern is used as the template 4z, a member having a flat surface without a concave-convex pattern (flat template) may also be used.

[0072] <Other embodiments> Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments and various modifications and changes are possible within the scope of the gist of the present invention.

[0073] The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program. It can also be realized by a circuit (e.g., ASIC) that realizes one or more functions.

[0074] The disclosure of this embodiment includes the following configuration. (Configuration 1) A film forming apparatus for forming a film of a curable composition on a substrate, a template holder for holding a template having an area that contacts the curable composition on the substrate; a substrate holder for holding the substrate; a detection means for detecting foreign matter present between the template and the substrate while the template is in contact with the substrate or the curable composition on the substrate, after a film formation process in which the curable composition on the substrate is cured while in contact with the template and the template is peeled off to form a film of the curable composition, and

[0075] (Configuration 2) a drive unit that drives at least one of the template holding unit and the substrate holding unit; 2. The film forming apparatus according to configuration 1, further comprising: a control unit that controls the driving unit.

[0076] (Configuration 3) The film forming apparatus according to Configuration 2, wherein the control unit causes the drive unit to change the horizontal relative positions of the template and the substrate after the film formation process has been performed at least once, and then causes the template to contact the curable composition on the substrate.

[0077] (Configuration 4) a supply unit for supplying the curable composition, 4. The film forming apparatus according to configuration 2 or 3, wherein the control unit controls the supply unit to supply the curable composition onto the substrate or the film at a thickness thinner than a thickness of the film before the template is brought into contact with the curable composition on the substrate.

[0078] (Configuration 5) the detection means includes a distance measuring sensor that measures a distance to a surface of the template opposite to a surface that comes into contact with the curable composition, The film forming apparatus according to any one of configurations 2 to 4, characterized in that the control unit acquires at least one of information on the presence or absence of the foreign matter, information on the size of the foreign matter, and information on the position of the foreign matter based on the measurement results of the distance measuring sensor.

[0079] (Configuration 6) 6. The film forming apparatus according to claim 5, wherein the distance measuring sensor further measures the distance to the surface of the substrate.

[0080] (Configuration 7) the detection means includes an imaging unit that acquires, as an image, an interference color generated by light reflected from the template and light reflected from the substrate; The film forming apparatus according to any one of configurations 2 to 6, wherein the control unit acquires at least one of information on the presence or absence of the foreign matter, information on the size of the foreign matter, and information on the position of the foreign matter based on the image acquired by the imaging unit.

[0081] (Configuration 8) When the foreign matter is detected by the detection means, the control unit controls the template to be cleaned and the detection unit to detect the foreign matter again. 8. The film forming apparatus according to any one of configurations 2 to 7, wherein:

[0082] (Configuration 9) the region is a flat surface, The film forming apparatus according to any one of configurations 1 to 8, wherein the film forming apparatus is a planarization apparatus that forms a planarized film on the substrate by contacting the flat surface of the template with the curable composition on the substrate.

[0083] (Configuration 10) 10. The film forming apparatus according to claim 9, wherein the template holding unit releases the template after bringing the template into contact with the curable composition on the substrate, and causes the template to conform to the surface shape of the curable composition on the substrate.

[0084] (Configuration 11) the region has a pattern to be transferred to the curable composition on the substrate; 9. The film forming apparatus according to any one of configurations 1 to 8, wherein the film forming apparatus is an imprint apparatus that transfers the pattern to the curable composition on the substrate by bringing the pattern of the template into contact with the curable composition on the substrate.

[0085] (Configuration 12) 12. The film forming apparatus according to any one of configurations 1 to 11, wherein the substrate used for detecting the foreign matter by the detecting means is a substrate on which the film is formed.

[0086] (Configuration 13) 12. The film forming apparatus according to any one of configurations 1 to 11, wherein the substrate used for detecting the foreign matter by the detecting means is a substrate different from the substrate on which the film is formed.

[0087] (Method 1) A film-forming method for forming a film of a curable composition on a substrate, comprising: a forming step of curing the curable composition on the substrate while the curable composition is in contact with a template, and then peeling the template and the curable composition to form a film of the curable composition; a detection step of detecting foreign matter between the template and the substrate while the template is in contact with the substrate or the curable composition on the substrate after the formation step; A film forming method comprising:

[0088] (Production method of article) forming a curable composition on a substrate using the film forming apparatus according to any one of configurations 1 to 13; treating the substrate on which the curable composition is formed; and producing an article from the processed substrate. [Explanation of symbols]

[0089] 1 Flattening device 2. Templates 3,43 PCB 4. Chuck 5 Contact Module 6 Substrate stage 7. Imaging unit 8 Measurement Sensors 9. Hardening Module 10 applicator 13 Control Unit

Claims

1. A film forming apparatus for forming a film of a curable composition on a substrate, a template holder for holding a template having an area that contacts the curable composition on the substrate; a substrate holder for holding the substrate; a detection means for detecting foreign matter present between the template and the substrate while the template is in contact with the substrate or the curable composition on the substrate, after a film formation process in which the curable composition on the substrate is cured while in contact with the template and the template is peeled off to form a film of the curable composition, and

2. a drive unit that drives at least one of the template holding unit and the substrate holding unit; The film forming apparatus according to claim 1 , further comprising: a control unit that controls the driving unit.

3. 3. The film forming apparatus according to claim 2, wherein the control unit causes the drive unit to change the horizontal relative positions of the template and the substrate after the film formation process has been performed at least once, and then causes the template to come into contact with the curable composition on the substrate.

4. a supply unit for supplying the curable composition, 3. The film forming apparatus according to claim 2, wherein the control unit controls the supply unit to supply the curable composition onto the substrate or the film at a thickness thinner than a thickness of the film before the template and the curable composition on the substrate come into contact with each other.

5. the detection means includes a distance measuring sensor that measures a distance to a surface of the template opposite to a surface that comes into contact with the curable composition, The film forming apparatus according to claim 2, characterized in that the control unit acquires at least one of information on the presence or absence of the foreign matter, information on the size of the foreign matter, and information on the position of the foreign matter based on the measurement results of the distance measuring sensor.

6. 6. The film forming apparatus according to claim 5, wherein the distance measuring sensor further measures the distance to the surface of the substrate.

7. the detection means includes an imaging unit that acquires, as an image, an interference color generated by light reflected from the template and light reflected from the substrate; The film forming apparatus according to claim 2, characterized in that the control unit acquires at least one of information on the presence or absence of the foreign matter, information on the size of the foreign matter, and information on the position of the foreign matter based on the image acquired by the imaging unit.

8. 3. The film forming apparatus according to claim 2, wherein, when the foreign matter is detected by the detection means, the control unit causes cleaning of the template and causes the detection means to detect the foreign matter again.

9. the region is a flat surface, 2. The film forming apparatus according to claim 1, wherein the film forming apparatus is a planarization apparatus that forms a planarized film on the substrate by contacting the flat surface of the template with the curable composition on the substrate.

10. 10. The film forming apparatus according to claim 9, wherein the template holding unit releases the template after bringing the template into contact with the curable composition on the substrate, and causes the template to conform to a surface shape of the curable composition on the substrate.

11. the region has a pattern to be transferred to the curable composition on the substrate; 2. The film forming apparatus according to claim 1, wherein the film forming apparatus is an imprint apparatus that transfers the pattern to the curable composition on the substrate by bringing the pattern of the template into contact with the curable composition on the substrate.

12. 2. The film forming apparatus according to claim 1, wherein the substrate used for detecting the foreign matter by the detecting means is a substrate on which the film is formed.

13. 2. The film forming apparatus according to claim 1, wherein the substrate used for detecting the foreign matter by the detecting means is a substrate different from the substrate on which the film is formed.

14. A film-forming method for forming a film of a curable composition on a substrate, comprising: a forming step of curing the curable composition on the substrate while the curable composition is in contact with a template, and then peeling the template and the curable composition to form a film of the curable composition; a detection step of detecting foreign matter between the template and the substrate while the template is in contact with the substrate or the curable composition on the substrate after the formation step; A film forming method comprising:

15. forming a curable composition on a substrate using the film forming apparatus according to any one of claims 1 to 13; treating the substrate on which the curable composition is formed; and producing an article from the processed substrate.

Images