Foreign object inspection method, foreign object inspection device, molding method, molding device, and manufacturing method for article

Abstract

To provide a new technology for a foreign object inspection method for inspecting a foreign object on a substrate.SOLUTION: The foreign object inspection method for inspecting a foreign object includes the steps for contacting a first surface of a first substrate and a second surface of a second substrate so that the first surface and the second surface face each other, acquiring an image of reflected light from the first surface and the second surface while the first surface and the second surface are in contact with each other, and determining the presence or absence of a foreign object or its position on the basis of the acquired image.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a foreign matter inspection method for inspecting a substrate for foreign matter, an inspection apparatus, a molding method, a molding apparatus, and a method for manufacturing an article. [Background technology]

[0002] Articles having a microstructure, such as semiconductor devices and MEMS, can be manufactured using a molding apparatus such as a projection exposure apparatus and / or an imprint apparatus. In such a microfabrication apparatus, the presence of foreign matter on a substrate can cause defects in the manufactured article. In particular, in a molding apparatus, a composition (curable composition) on a substrate is brought into contact with a mold to mold the composition, and therefore, foreign matter present on the substrate can damage the mold or shorten the life of the mold.

[0003] Therefore, in order to prevent damage to the mold or shortening of the mold's lifespan, a substrate inspection device (foreign matter inspection device) is used to inspect the substrate for foreign matter in advance. For example, a typical substrate inspection device as shown in Patent Document 1 is configured as a device that detects the presence or absence of foreign matter by irradiating inspection light onto the substrate at an oblique incidence and receiving light scattered from the foreign matter with a light receiving unit.

[0004] Furthermore, Patent Document 2 exemplifies a technology in which a mold with concaves and convexes formed thereon is brought into contact with a liquid imprint resist in an imprint method, and then interference fringes are imaged through the transparent mold, and foreign objects are detected from abnormal patterns in the interference fringes. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2022-29829 [Patent Document 2] Patent No. 6541518 Summary of the Invention [Problem to be solved by the invention]

[0006] Conventional foreign body inspection devices such as that described in Patent Document 1 had problems such as being unable to detect tiny foreign bodies (e.g., 500 nm or less) below the light scattering limit based on the light receiving sensitivity of the optical receiver, and requiring a long inspection time.

[0007] Furthermore, the technology for detecting foreign objects during imprinting described in Patent Document 2 has the problem that although it can detect that a foreign object has been trapped, it cannot avoid the foreign object itself, and it cannot detect small foreign objects that are below the resolution limit of the imaging device (e.g., 70 μm).

[0008] An exemplary object of the present invention is to provide a new technique relating to a foreign matter inspection method for inspecting a substrate for foreign matters. [Means for solving the problem]

[0009] In order to achieve the above object, a foreign body inspection method according to one aspect of the present invention includes: A foreign body inspection method for inspecting foreign bodies, comprising the steps of: contacting a first surface of the first substrate with a second surface of the second substrate such that the first surface and the second surface face each other; acquiring images of reflected light from the first surface and the second surface while the first surface and the second surface are in contact with each other; determining the presence or location of a foreign object based on the acquired image; The present invention is characterized by having the following.

[0010] Further objects or other aspects of the present invention will become apparent from the following description of the embodiments with reference to the accompanying drawings. Effect of the Invention

[0011] According to the present invention, a new technique can be provided for a foreign matter inspection method for inspecting a substrate for foreign matter. [Brief description of the drawings]

[0012] [Figure 1]FIG. 1 is a schematic diagram of an example of a foreign matter inspection device according to an embodiment. [Diagram 2] 3 is a flowchart of a foreign matter inspection method according to an embodiment. [Diagram 3] FIG. 4 is a schematic diagram of a state before the first substrate and the second substrate are brought into contact with each other. [Figure 4] Schematic diagram of the principle of foreign object detection. [Diagram 5] Schematic diagram of the principle behind interference color generation. [Figure 6] 2 shows an example of the shape of the first substrate of the present invention. [Figure 7] 1 shows an example of a method for contacting a first substrate and a second substrate of the present invention. [Figure 8] Images taken in Example 1. [Figure 9] Image taken in Example 2. [Figure 10] Schematic diagram showing the difference in area of ​​the interference color anomalous region depending on whether or not a liquid film is present. [Figure 11] Schematic diagram of an example of manufacturing an article of an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, the embodiments will be described in detail with reference to the attached drawings. Note that the following embodiments do not limit the invention according to the claims. Although the embodiments describe a number of features, not all of these features are essential to the invention, and the features may be combined in any manner. Furthermore, in the attached drawings, the same reference numbers are used for the same or similar configurations, and duplicated descriptions are omitted.

[0014] (Foreign body inspection device) The foreign matter inspection device of this embodiment includes a first holding section that holds a first substrate, a second holding section that holds a second substrate, a drive mechanism that brings the first surface of the first substrate and the second surface of the second substrate into contact with each other so that the first surface and the second surface face each other, an image acquisition section that acquires images of reflected light from the first surface and the second surface while the first surface and the second surface are in contact with each other, and a control section that determines the presence or position of a foreign matter based on the acquired images.

[0015] Fig. 1 is a diagram showing the configuration of a foreign matter inspection device 1 according to this embodiment. The configuration of the foreign matter inspection device 1 will be described with reference to Fig. 1. Here, the surface on which the second substrate 10 is arranged is defined as the XY plane, and the direction perpendicular thereto is defined as the Z direction, and each axis is determined as shown in Fig. 1.

[0016] Glass, ceramics, metal, semiconductor, resin, etc. are used for the first substrate 8 and the second substrate 10, and a member made of a material different from that of the substrate may be formed on the surface thereof as necessary. Specific examples of the substrate include a silicon wafer, a compound semiconductor wafer, and quartz glass.

[0017] The first substrate 8 is preferably a transparent substrate made of a material that transmits light. The first substrate 8 may have a mesa portion 8a having a flat top surface. Here, the mesa portion 8a is a plateau-shaped portion that protrudes from the surrounding area and has a top surface that is a contact surface of the first substrate 8 that is to be imprinted on the second substrate 10.

[0018] On the other hand, the second substrate may be made of a material that is opaque to light.

[0019] At least one of the first substrate and the second substrate must be made of a material that transmits light, but both may be transparent.

[0020] The substrate to be inspected for foreign matter may be either the first substrate or the second substrate. Examples include a configuration in which the first substrate is a quartz glass wafer used in planarization processing called a superstrate, and a configuration in which the second substrate is a silicon wafer as a substrate to be processed for nanoimprinting. This method is applicable whether the substrate to be inspected is transparent or non-transparent.

[0021] If the first surface of the first substrate and the second surface of the second substrate are substantially the same size, the inspection can be completed by performing the contacting step described below once. On the other hand, if the size of the first surface of the first substrate is smaller than the size of the second surface of the second substrate, the contact position between the first surface and the second surface may be changed to repeatedly inspect multiple areas of the second surface.

[0022] The foreign matter inspection device 1 includes a first holding unit 3 that holds and moves a first substrate 8, and a second holding unit 4 that holds and moves a second substrate 10.

[0023] The foreign body inspection device 1 also includes a light irradiation system 2 that guides light 9 to irradiate the first and second surfaces, an imaging unit 6 that images the reflected light from the first and second surfaces, and a control unit 7 that controls the operation of the foreign body inspection device 1.

[0024] Furthermore, the foreign matter inspection apparatus 1 may include a detector 12 that detects marks formed on the first substrate and the second substrate.

[0025] The second holding unit 4 includes a substrate chuck 16 that holds the second substrate 10, and a substrate driving mechanism 17 that controls the position of the second substrate 10 with respect to at least two axes, the X-axis direction and the Y-axis direction, in the XYZ coordinate system.

[0026] In addition, the second holding unit 4 has a plurality of reference mirrors 18 on its side surface corresponding to the X, Y, Z, ωx, ωy, and ωz directions.

[0027] Correspondingly, the foreign matter inspection device 1 is provided with a plurality of laser interferometers 19 (length measuring devices) so that the position of the second holding part 4 can be measured by irradiating each of these reference mirrors 18 with a beam.

[0028] The laser interferometer 19 measures the position of the second holding unit 4, and the control unit 7 executes positioning control of the second substrate 10 (or the second holding unit 4) based on the measurement value at this time.

[0029] The foreign matter inspection device 1 may measure the position of the second holding part 4 using an encoder instead of the reference mirror 18 and the laser interferometer 19.

[0030] Furthermore, the second holding part 4 may have a substrate chuck 16 that holds the second substrate 10 from the lower surface, and may be provided with spaces partitioned by a plurality of substrate chucks 16. By adjusting the pressure in each of the partitioned spaces, the second substrate 10 can be deformed during imprinting or demolding.

[0031] For example, by increasing the pressure in the space during imprinting, the second substrate 10 can be deformed into a convex shape relative to the first substrate 8, so that the flat first surface and the second surface of the second substrate 10 can be brought into contact with each other.

[0032] The first holding part 3, with the first substrate 8 held by the first chuck 11, is moved in the vertical direction (Z-axis direction) by a first driving mechanism 38 (actuator) provided in the first holding part.

[0033] When the first holding portion 3 is moved downward (in the -Z direction) by the first driving mechanism 38, the (first surface of) mesa portion 8a of the first substrate 8 comes into contact with the surface (second surface) of the second substrate.

[0034] After the foreign substance inspection is completed, the first holder 3 is moved upward (in the +Z direction) by the first drive mechanism 38, whereby the first substrate 8 is separated from the second substrate.

[0035] In the contact step and the separation step, the second holding part 4 may move in the Z-axis direction instead of the first holding part 3, or the first holding part 3 and the second holding part 4 may move relatively to each other.

[0036] Furthermore, the first holding unit 3 may be provided with a space 13 partitioned by a light transmitting member 41 (e.g., a quartz plate) and the first substrate 8, and the first substrate 8 can be deformed at the time of contact or separation by adjusting the pressure within the space 13. For example, by increasing the pressure within the space 13 at the time of contact, the first substrate 8 can be deformed into a convex shape relative to the second substrate 10, and the mesa portion 8a (first surface) can be brought into contact with the second surface.

[0037] It is preferable that the deformation of the first holding portion 3 is controlled in conjunction with the deformation of the second holding portion 4 described above.

[0038] The detector 12 can detect the marks formed on the first substrate 8 and the marks formed on the second substrate 10.

[0039] The foreign matter inspection device 1 can determine the relative positions of the first substrate 8 and the second substrate 10 based on the detection results of the detector 12, and can align the first substrate 8 and the second substrate 10 by moving at least one of the first substrate 8 and the second substrate 10.

[0040] The control unit 7 brings the first surface into contact with one or more shot areas formed on the second substrate 10, and controls the operation of each mechanism of the foreign matter inspection device 1 to perform foreign matter inspection. The control unit 7 can also be configured to control the first holding unit 3, the second holding unit 4, the supply mechanism 5, the light irradiation system 2, and the detector 12. The control unit 7 may be provided within the foreign matter inspection device 1, or may be provided in a location separate from the foreign matter inspection device 1 and controlled remotely.

[0041] The above foreign matter inspection device can be made into a molding device by providing a supply unit 5 for a curable composition. Also, a mechanism for irradiating light 35 may be provided to the imaging unit 6, and the light irradiation system 2 may be a light irradiation system for irradiating ultraviolet light for curing the curable composition. In this case, it is necessary to configure the first holding unit to be able to hold a template such as an imprint mold on which a concave-convex pattern is formed. By using an imprint mold as the template, the device can be made into a molding device (imprint device) that molds the curable composition supplied onto the second substrate into a concave-convex pattern. Also, by using a superstrate having a flat surface as the template held by the first holding unit, the device can be used as a molding device (flattening device) that flattens the surface of the second substrate.

[0042] (Explanation of foreign body inspection method) FIG. 2 is a flowchart showing each process when foreign matter present on the second surface of second substrate 10 is inspected by foreign matter inspection device 1 through contact between the second surface of second substrate 10 and the first surface of first substrate 8.

[0043] First, in step 101, the second substrate 10 is carried into the foreign matter inspection apparatus 1. The second substrate 10 is carried into the second chuck 16 of the second holding unit 4 by a substrate transport mechanism (not shown).

[0044] In step 102, the first substrate 8 and the second substrate 10 are aligned before being brought into contact with each other. For example, the first substrate 8 and the second substrate 10 are aligned by detecting light from a mark formed on the first substrate 8 and a mark formed on the second substrate 10 with a detector 12.

[0045] In step 103, the first substrate 8 and the second substrate 10 are brought close to each other, thereby bringing the second surface of the second substrate 10 into contact with the first surface of the first substrate 8 (contact step). At this time, no liquid such as imprint resist is present between the first surface and the second surface.

[0046] In step 104, light 9 is irradiated from light irradiation system 2 while the first surface of first substrate 8 and the second surface of second substrate 10 are in contact with each other (light irradiation step). Light irradiation system 2 irradiates at least the entire mesa portion 8a having the second surface.

[0047] In step 105, images of the reflected light from the first and second surfaces are acquired to inspect for foreign matter (image acquisition step).

[0048] From the image obtained in step 105, the presence or absence of a foreign object is detected or the position of the foreign object is determined (step 106).

[0049] Thereafter, in step 107, the first substrate 8 and the second substrate 10 are separated (peeling step).

[0050] After the second substrate 10 is separated from the first substrate 8 in step 107, an end determination is made in step 108 as to whether the foreign substance inspection process has been completed for the shot area specified on the substrate 10. If the foreign substance inspection process has been completed in step 108, the substrate 10 is carried out of the foreign substance inspection apparatus 1 in step 109. If the foreign substance inspection process has not been completed, the process returns to step 102, where the first substrate and the second substrate are moved relatively to the next inspection position (shot area), and each step is repeated until the foreign substance inspection process is completed.

[0051] (Principle of foreign body inspection) The principle of foreign object detection according to the present invention will be described with reference to FIGS.

[0052] Figure 3 is a schematic diagram showing the state before the first and second substrates are brought into contact, and Figure 3(A) shows an embodiment in which the first substrate is a clean and transparent substrate and the second substrate is an opaque substrate to be inspected, and Figure 3(B) shows an embodiment in which the first substrate is a transparent substrate to be inspected and the second substrate is a clean and opaque substrate.

[0053] When a foreign object is attached to the substrate to be inspected, a gap will be created between the second substrate and the first substrate depending on the height of the foreign object, as shown in Figure 4. This gap will become a space that expands around the foreign object due to bending of at least one of the substrates. The area where the gap is created is called the non-contact area, and the area where the second substrate and the first substrate are in contact with each other and the gap is essentially zero nm is called the contact area.

[0054] When illumination light is irradiated through the transparent first substrate 8 or second substrate, light is reflected between the first surface of the first substrate and the second surface of the second substrate. Since the intensity of the reflected light differs between the contact area and the non-contact area, the presence of a foreign object in the non-contact area can be detected as a difference in the intensity of light received by the imaging unit.

[0055] The reason why the reflected light intensity differs between the contact area and the non-contact area will be explained using Figure 5. In the contact area, the illumination light is reflected mainly at the interface between the first and second substrates. In the non-contact area, because air exists in the gap between the first and second substrates, the illumination light is reflected from two different interfaces: the first substrate-air interface and the air-second substrate interface. These two types of interface reflected light interfere with each other, and the degree of interference is determined by the reflected light intensity depending on the interface distance between the first and second substrates. In other words, the reflected light intensity contains information about the distance between the first and second substrates, i.e., the height of the foreign object.

[0056] When the wavelength of the irradiated light is λ nm, the reflected light intensity is minimal when the distance between the first and second substrates is λ / 4, and is maximal when it is λ / 2. For example, when 405 nm monochromatic light is used as the illumination light, a foreign object with a height of approximately 101 nm can be detected by imaging as an area with minimal reflected light.

[0057] When the second substrate is used as the substrate to be inspected, the surface of the inspection area of ​​the first substrate to be used must be free of foreign matter and optically flat. For this reason, it is preferable to clean the first substrate before inspection to remove foreign matter. It is also preferable to inspect the first substrate to confirm that there is no foreign matter, and to confirm the flatness of the first substrate.

[0058] Such devices for cleaning, removing foreign matter, and inspecting the flatness of a solid phase are available in the semiconductor industry as cleaning devices, foreign matter inspection devices, and surface shape measurement devices, respectively.

[0059] Cleaning equipment and foreign matter inspection equipment that can handle wafer-shaped or square substrates measuring 6 inches square and 0.25 inches thick are widely available. For this reason, it is preferable that the shape of the first and second substrates be wafer-shaped or square substrates measuring 6 inches square and 0.25 inches thick.

[0060] (Forming process of substrate after foreign body inspection) The second substrate is inspected by the above-mentioned foreign matter inspection method, and the apparatus is controlled so as to carry out a molding process such as imprinting only in an area on the second substrate where it has been determined that no foreign matter is present.

[0061] As described above, this may be performed using a forming apparatus incorporated in a foreign matter inspection apparatus, or the second substrate may be carried into a separate imprint apparatus and the forming process may be performed therein.

[0062] It is also preferable to inspect the second substrate and control the forming device (imprinting device) so that a forming process (imprinting) is not performed on an area on the second substrate where the position of a foreign object has been determined.

[0063] The method may further include a step of inspecting the second substrate by the above-mentioned foreign matter inspection method, and cleaning the second substrate on which foreign matter of a predetermined size or a predetermined number or more is determined to be present.

[0064] The present invention will be described below using more specific embodiments.

[0065] (First embodiment) In this embodiment, an example of a first substrate is shown in Fig. 6. The first substrate has a first surface and a second surface, the second surface has a recessed portion recessed toward the first surface, and the first surface has a protruding step structure, and the step structure is formed in a narrow region inside the recessed portion.

[0066] Fig. 6(A) is a schematic cross-sectional view of an example of a first substrate, Fig. 6(B) is a schematic plan view of an example of the first substrate, and Fig. 6(B) is a cross-sectional view taken along line AA in Fig. 6(A).

[0067] The first substrate 110 has a first main surface 111, which serves as a first surface, and a second main surface 112 on a transparent base material, and has a convex step structure (mesa structure) 114 in which an inspection area 113 on the first main surface 111 is higher than the surrounding area. The second main surface 112 opposite to the first main surface 111 has a depression 115 that overlaps with the inspection area 113 on the first main surface and has an area larger than that of the inspection area 113 on the first main surface. The convex step structure is located in the center of the base material, and its area is 10% or less and 0.5% or more of the area of ​​the first main surface of the base material.

[0068] The size of the first substrate 110 is preferably 6 inches square and 0.25 inches thick. The material of the first substrate 110 is a highly elastic material with an elastic modulus of 50 GPa or more, and quartz glass is particularly preferred. Quartz glass substrates of the above size are widely used as photomask base materials in the semiconductor industry.

[0069] A contact method in which the first surface (principal surface 111) of the first substrate and a part of the second surface of the second substrate are brought into contact with each other, and then the contact area is expanded to the entire inspection area, is described with reference to FIG. 7. The recessed portion of the first substrate is sealed and nitrogen gas is flowed into the recessed portion, and the pressure in the sealed recessed portion is set to, for example, 1.5 atmospheres, and the recessed portion is curved in a convex shape toward the second substrate (FIG. 7[1]). With the inspection region of the first substrate curved, the first substrate is lowered, and only the center portion of the inspection region (FIG. 7[2]) is brought into contact with the second substrate. While applying an imprinting force of, for example, up to 42 N, the first substrate is gradually brought into contact with the second substrate toward the outer periphery (FIG. 7[3]). When the entire inspection region is in close contact with the second substrate (FIG. 7[4]), the pressure in the recessed portion is released to atmospheric pressure. In the process of FIG. 7[2]-[3], the inspection region is irradiated with illumination light and the reflected light is captured, thereby detecting foreign objects present in the inspection region.

[0070] Second embodiment A second embodiment of the foreign matter inspection of the present invention will be described with reference to FIG. 1 and FIG.

[0071] In this embodiment, a second substrate that is opaque to the illumination light is to be inspected as shown in Fig. 3(A) A first substrate 8 that is transparent to the illumination light is held by a first holder 3 as shown in Fig. 1 .

[0072] The first driving mechanism 38 brings the first substrate and the opaque second substrate closer to each other so that a portion of the first substrate comes into contact with the opaque second substrate, and then the first substrate is brought into contact with the opaque second substrate so that the contact area between the first substrate and the opaque substrate is increased.

[0073] Then, illumination light is irradiated from the light irradiation system 2 through the first substrate, and the area sandwiched between the opaque substrate and the first substrate is imaged by the imaging unit 6, and an interference color generated by the reflected light from the first substrate and the reflected light from the opaque substrate is obtained as an image.

[0074] At the time of contact, substantially no liquid such as an imprint material is present in the gap between the opaque second substrate and the first substrate, and the presence and positional information of a foreign object on the opaque substrate can be determined based on the interference color of the image acquired by the imaging unit 6.

[0075] Third embodiment A third embodiment of the foreign matter inspection of the present invention will be described with reference to FIG. 1 and FIG.

[0076] In this embodiment, as shown in FIG. 3(B), a first substrate that is transparent to illumination light is the object to be inspected.

[0077] As shown in FIG. 1, a first substrate 8 that is transparent to illumination light is held by a first holding portion 3.

[0078] The first driving mechanism 38 brings the first substrate and the second substrate closer to each other so that a portion of the first substrate comes into contact with the opaque second substrate, and then the first substrate is brought into contact with the opaque second substrate so that the contact area between the first substrate and the opaque second substrate is increased.

[0079] Then, illumination light is irradiated from the light irradiation system 2 through the first substrate, and the area sandwiched between the opaque second substrate and the first substrate is imaged by the imaging unit 6, thereby obtaining an image of the interference color produced by the light reflected from the first substrate and the light reflected from the opaque substrate.

[0080] At the time of contact, substantially no liquid is present in the gap between the opaque second substrate and the first substrate, and the presence and position information of a foreign object on the opaque substrate can be determined based on the interference color of the image captured by the imaging unit 6.

[0081] (Embodiments of manufacturing the article) The present invention can also be applied to the manufacture of articles. An embodiment of the manufacture of articles to which the present invention is applied will be described with reference to FIG.

[0082] The pattern of the cured product of the curable composition formed by using the molding device is used permanently on at least a part of various articles, or temporarily when manufacturing various articles. The article is an electric circuit element, an optical element, a MEMS, a recording element, a sensor, a mold, etc. Examples of the electric circuit element include volatile or non-volatile semiconductor memories such as DRAM, SRAM, flash memory, and MRAM, and semiconductor elements such as LSI, CCD, image sensor, and FPGA. Examples of the optical element include a diffraction grating and a polarizing plate. Examples of the mold include a mold for imprinting (replica mold), etc.

[0083] The pattern of the cured product is used as it is as at least a part of a component of the article, or is used temporarily as a resist mask, which is removed after etching or ion implantation in a substrate processing step.

[0084] Next, a specific method for manufacturing the article will be described. As shown in Fig. 11(a), a substrate 1z such as a silicon wafer having a workpiece 2z such as an insulator formed on its surface is prepared, and then a curable composition 3z is applied to the surface of the workpiece 2z by an inkjet method or the like. Here, a state in which the curable composition 3z in the form of multiple droplets is applied onto the substrate is shown.

[0085] As shown in Fig. 11(b), the imprinting mold 4z is placed facing the curable composition 3z on the substrate with the side on which the concave-convex pattern is formed. As shown in Fig. 11(c), the substrate 1z to which the curable composition 3z is applied is brought into contact with the mold 4z, and pressure is applied. The curable composition 3z fills the gap between the mold 4z and the workpiece 2z. In this state, when light is irradiated as energy for curing through the mold 4z, the curable composition 3z is cured.

[0086] As shown in Fig. 11(d), after the curable composition 3z is cured, the mold 4z and the substrate 1z are separated, and a pattern of the cured product of the curable composition 3z is formed on the substrate 1z. In this cured product pattern, the recesses of the mold correspond to the protruding parts of the cured product, and the recesses of the mold correspond to the protruding parts of the cured product, that is, the recessed and protruding pattern of the mold 4z is transferred to the curable composition 3z.

[0087] As shown in Fig. 11(e), when etching is performed using the pattern of the cured material as an etching-resistant mask, the portion of the surface of the workpiece 2z where there is no cured material or where only a thin layer of the cured material remains is removed, forming the grooves 5z. It is also preferable to remove the remaining portion in advance by a different type of etching from the etching.

[0088] As shown in Fig. 11(f), when the pattern of the cured product is removed, an article having grooves 5z formed on the surface of the workpiece 2z can be obtained. For example, when a silicon wafer is used as the substrate 1z, an element for an electric circuit such as a semiconductor element, a MEMS, a recording element, a sensor, etc. can be obtained as an article. When quartz is used as the substrate 1z, a replica mold, an optical element, etc. can be obtained as an article.

[0089] Here, the pattern of the cured product was removed, but it may be used without being removed after processing, for example, as an interlayer insulating film contained in a semiconductor element or the like, or as a pattern structure of an optical material that constitutes an optical element, that is, as a constituent member of an article. EXAMPLES

[0090] The present invention will now be described in more detail with reference to examples.

[0091] (Example 1) Step-and-repeat inspection of an opaque second substrate using a transparent first substrate The inspection target was a silicon wafer with a diameter of 300 mm, and the inspection area was 26 × 33 mm on the first substrate made of quartz glass shown in Figure 4. The inspection area was imaged at 60 frames / sec using the contact method shown in Figure 7, which does not involve any liquid such as resist. Figure 8 shows the frame-by-frame images.

[0092] The foreign object located in the lower center of the inspection area was detected within 0.25 seconds after contact began. Since there was only one ring-shaped dark area around the foreign object, the height of the foreign object was estimated to be higher than λ / 4 and lower than 3λ / 4.

[0093] By repeating a similar inspection method while moving the inspection area, it is possible to inspect the entire area of ​​a silicon wafer with a diameter of, for example, 300 mm for foreign bodies.

[0094] (Example 2) Full-surface inspection of transparent second substrate using opaque first substrate The test object was a quartz wafer with a diameter of 300 mm, and a clean and flat silicon wafer was prepared as the first opaque substrate. With the quartz wafer and silicon wafer facing each other, the center of the quartz wafer was bent toward the silicon wafer, and after the center was in contact, the quartz wafer and silicon wafer were contacted sequentially from the center to the edge over a period of 10 seconds. A still image was taken with the entire surfaces in contact, and many foreign objects were detected.

[0095] (Example 3) Theoretical calculation of non-contact area caused by foreign matter The deformation behavior of the first substrate used in Example 1 caused by sandwiching a foreign object was analyzed using Dassault Systèmes' finite element analysis software Abaqus. A quartz glass first substrate was brought into contact with a silicon wafer with a diameter of 300 mm and an elastic modulus of 190 GPa, on which a cylindrical foreign object with a height of 0.1 μm was placed, from the center of the inspection area, and an imprinting force of 42 N was applied. It was calculated that a non-contact area with a diameter of approximately 260 μm would be generated around the foreign object (FIG. 10(A)). The presence of the foreign object could be detected because an interference color anomaly occurred in an area with a diameter of approximately 260 μm, which exceeds the resolution of the digital still camera used for imaging (70 μm).

[0096] (Comparative Example 1) Theoretical calculation of non-contact area caused by foreign matter The deformation behavior of the first substrate was calculated when a 50 nm thick liquid film was formed between the first and second substrates under the same conditions as in Example 3 for the first substrate, second substrate, and foreign object. Due to the presence of the liquid film, the first surface of the first substrate and the second surface of the second substrate do not come into direct contact with each other. The meniscus pressure due to the liquid film was calculated to be 1.18 MPa. The non-contact area formed around the foreign object was calculated to have a diameter of about 11 μm (FIG. 10(B)). It is considered that the first substrate was strongly attracted toward the second substrate by the meniscus pressure, and the first substrate was deformed following the foreign object, so that the non-contact area became narrower than in Example 3. The interference color anomalous area was about 11 μm in diameter, which is below the resolution of 70 μm of the digital still camera used for imaging, and therefore the interference color anomalous area could not be detected, i.e., the foreign object could not be detected.

[0097] <Summary of the embodiment> The disclosure of this specification includes a foreign object inspection method, a foreign object inspection apparatus, an imprint method, a molding apparatus, and an article manufacturing method.

[0098] (Item 1) A foreign body inspection method for inspecting foreign bodies, comprising the steps of: contacting a first surface of the first substrate with a second surface of the second substrate such that the first surface and the second surface face each other; acquiring images of reflected light from the first surface and the second surface while the first surface and the second surface are in contact with each other; determining the presence or location of a foreign object based on the acquired image; 1. A foreign body inspection method comprising the steps of:

[0099] (Item 2) 2. The foreign body inspection method according to item 1, wherein the first substrate is made of a material that transmits light.

[0100] (Item 3) 3. The foreign body inspection method according to item 2, further comprising the step of irradiating the first surface and the second surface with light through the first substrate.

[0101] (Item 4) 4. The foreign body inspection method according to any one of items 1 to 3, wherein the contacting step is a step of contacting the first surface and the second surface such that a contact region where the first surface and the second surface are in contact and a non-contact region where the first surface and the second surface are not in contact due to a foreign body are formed.

[0102] (Item 5) 5. The foreign body inspection method according to item 4, wherein the step of acquiring the image is a step of acquiring an image of the non-contact area extending around the foreign body by bending at least one of the first surface and the second surface due to the presence of a foreign body.

[0103] (Item 6) 6. The foreign body inspection method according to any one of items 3 to 5, wherein the second substrate is made of a material that is opaque to the light.

[0104] (Item 7) 7. The foreign matter inspection method according to claim 6, wherein the first substrate is an inspection target substrate.

[0105] (Item 8) 7. The foreign matter inspection method according to claim 6, wherein the second substrate is an inspection target substrate.

[0106] (Item 9) 9. The foreign body inspection method according to any one of items 2 to 8, wherein the first substrate is a quartz wafer.

[0107] (Item 10) 10. The foreign body inspection method according to any one of items 6 to 9, wherein the second substrate is a silicon wafer.

[0108] (Item 11) 11. The foreign body inspection method according to any one of items 1 to 10, wherein the first surface of the first substrate and the second surface of the second substrate are approximately the same size.

[0109] (Item 12) 11. The foreign body inspection method according to any one of items 1 to 10, characterized in that a size of the first surface of the first substrate is smaller than a size of the second surface of the second substrate, and inspection is repeatedly performed on a plurality of regions of the second surface by changing a contact position between the first surface and the second surface.

[0110] (Item 13) 13. The foreign body inspection method according to any one of items 3 to 12, wherein the irradiated light is monochromatic light.

[0111] (Item 14) 14. An imprinting method, comprising: inspecting the second substrate by the foreign matter inspection method according to any one of items 8 to 13; and controlling an imprinting apparatus to perform imprinting only in an area on the second substrate where it has been determined that no foreign matter is present.

[0112] (Item 15) 9. An imprinting method comprising: inspecting the second substrate by the foreign matter inspection method according to item 8; and controlling an imprinting apparatus so as not to perform imprinting in an area on the second substrate where the position of the foreign matter has been determined.

[0113] (Item 16) 9. An imprinting method comprising: inspecting the second substrate by the foreign matter inspection method according to item 8; and cleaning the second substrate determined to have foreign matters of a predetermined size or more or a predetermined number or more.

[0114] (Item 17) A foreign body inspection device for inspecting foreign bodies, comprising: a first holding portion that holds a first substrate; A second holding portion that holds the second substrate; a drive mechanism that brings the first surface of the first substrate and the second surface of the second substrate into contact with each other so that the first surface and the second surface of the second substrate face each other; an image acquisition unit that acquires images of reflected light from the first surface and the second surface in a state in which the first surface and the second surface are in contact with each other; A control unit that determines the presence or absence and position of a foreign object based on the acquired image; A foreign body inspection device comprising:

[0115] (Item 18) Item 18. The foreign body inspection apparatus according to item 17, further comprising a light irradiation unit that irradiates the first surface and the second surface with light.

[0116] (Item 19) Item 18. A foreign body inspection device according to item 18, a supply unit that supplies a curable composition to the second substrate, The first holding portion is capable of holding a template, The curable composition supplied to the second substrate is brought into contact with the template by the driving mechanism, and the curable composition is cured by the light irradiation unit. A molding apparatus comprising:

[0117] (Item 20) 1. A method for manufacturing an article, comprising: 20. Molding the composition on a substrate using a molding apparatus according to item 19; and processing the substrate that has been subjected to the molding step, A method for manufacturing an article, comprising the steps of: manufacturing an article from the substrate that has been subjected to the processing step. [Explanation of symbols]

[0118] 1 Foreign body inspection equipment, molding equipment 3 1st holding part 4 Second holding part 6. Imaging unit 7 Control section 8, 110 First board 10 Second board

Claims

1. A foreign body inspection method for inspecting foreign bodies, comprising the steps of: contacting a first surface of the first substrate with a second surface of the second substrate such that the first surface and the second surface face each other; acquiring images of reflected light from the first surface and the second surface in a state in which the first surface and the second surface are in contact with each other; determining the presence or location of a foreign object based on the acquired image; 1. A foreign body inspection method comprising the steps of:

2. 2. The foreign body inspection method according to claim 1, wherein the first substrate is made of a material that transmits light.

3. 3. The foreign body inspection method according to claim 2, further comprising the step of irradiating the first surface and the second surface with light through the first substrate.

4. 2. The foreign body inspection method according to claim 1, wherein the contacting step is a step of contacting so as to form a contact area where the first surface and the second surface are in contact and a non-contact area where the first surface and the second surface are not in contact due to a foreign body.

5. 5. The foreign body inspection method according to claim 4, wherein the image acquiring step acquires an image of the non-contact area extending around the foreign body by bending at least one of the first surface and the second surface due to the presence of the foreign body.

6. 4. The foreign matter inspection method according to claim 3, wherein the second substrate is made of a material that is opaque to the light.

7. 7. The foreign matter inspection method according to claim 6, wherein the first substrate is an inspection target substrate.

8. 7. The foreign matter inspection method according to claim 6, wherein the second substrate is an inspection target substrate.

9. 3. The foreign matter inspection method according to claim 2, wherein the first substrate is a quartz wafer.

10. 7. The method for inspecting for foreign matter according to claim 6, wherein the second substrate is a silicon wafer.

11. 2. The foreign body inspection method according to claim 1, wherein the first surface of the first substrate and the second surface of the second substrate have substantially the same size.

12. 2. The foreign body inspection method according to claim 1, wherein a size of the first surface of the first substrate is smaller than a size of the second surface of the second substrate, and inspection is repeatedly performed on multiple areas of the second surface by changing a contact position between the first surface and the second surface.

13. 4. The foreign body inspection method according to claim 3, wherein the irradiated light is monochromatic light.

14. A molding method comprising the steps of: inspecting the second substrate by the foreign matter inspection method according to claim 8; and controlling an apparatus so as to perform molding processing only on an area on the second substrate where it is determined that no foreign matter is present.

15. A molding method comprising: inspecting the second substrate by the foreign matter inspection method according to claim 8; and controlling an apparatus so that molding processing is not performed in an area on the second substrate where the position of the foreign matter on the second substrate has been determined.

16. 9. A molding method comprising the steps of: inspecting the second substrate by the foreign matter inspection method according to claim 8; and cleaning the second substrate on which foreign matter of a predetermined size or a predetermined number or more is determined to be present.

17. A foreign body inspection device for inspecting foreign bodies, comprising: A first holding portion that holds a first substrate; A second holding portion that holds a second substrate; a drive mechanism that brings the first surface of the first substrate and the second surface of the second substrate into contact with each other such that the first surface and the second surface of the second substrate face each other; an image capturing unit that captures images of reflected light from the first surface and the second surface in a state in which the first surface and the second surface are in contact with each other; A control unit that determines the presence or absence and position of a foreign object based on the acquired image; A foreign body inspection device comprising:

18. 18. The foreign matter inspection device according to claim 17, further comprising a light irradiation unit that irradiates the first surface and the second surface with light.

19. The foreign matter inspection device according to claim 18 , a supply unit that supplies a curable composition to the second substrate, The first holding portion is capable of holding a template, The curable composition supplied to the second substrate is brought into contact with the template by the driving mechanism, and the curable composition is cured by the light irradiation unit. A molding apparatus comprising:

20. 1. A method for manufacturing an article, comprising:

20. Molding a composition on a substrate using a molding apparatus according to claim 19; and processing the substrate that has been subjected to the molding step, A method for manufacturing an article, comprising the steps of: manufacturing an article from the substrate that has been subjected to the processing step.

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