Foreign matter inspection method and apparatus, molding method, molding apparatus, and article manufacturing method

Abstract

The invention provides a foreign matter inspection method and apparatus, a molding method, a molding apparatus, and an article manufacturing method. A foreign matter inspection method for inspecting a foreign matter includes: bringing a first surface of a first substrate into contact with a second surface of a second substrate so that the first surface and the second surface face each other; obtaining an image of reflected light from the first surface and the second surface in contact with each other; and determining the presence, absence, or location of a foreign matter based on the obtained image.

Description

Technical Field

[0001] The present disclosure relates to a foreign matter inspection method, an inspection device, a molding method, a molding device, and an article manufacturing method for inspecting foreign matter in a substrate. Background Art

[0002] Articles with fine structures such as semiconductor devices or micro-electromechanical systems (MEMS) devices can be manufactured by using a projection exposure device and / or a molding device such as an imprinting device. In such a micro-machining device, foreign matter on the substrate may cause defects in the article to be manufactured. In particular, in a molding device that molds a composition (curable composition) on a substrate by bringing the mold into contact with the composition, foreign matter on the substrate may damage the mold or shorten the life of the mold.

[0003] In order to reduce the damage of the mold or the shortening of the mold life, a substrate inspection device (foreign matter inspection device) is used in advance to inspect foreign matter in the substrate. A typical substrate inspection device (such as the device disclosed in Japanese Patent Publication No. 2022-29829) is configured to detect the presence of foreign matter by irradiating the substrate with obliquely incident inspection light and receiving light scattered by the foreign matter through a photodetector.

[0004] Japanese Patent No. 6541518 discloses a technique of contacting a transparent mold having protrusions and depressions with a liquid imprint resist in an imprinting manner, and also includes taking an image of interference fringes through the mold to detect foreign matter based on abnormal patterns of the interference fringes.

[0005] Known foreign matter inspection devices (such as the device disclosed in Japanese Patent Application Laid-Open No. 2022-29829) have limited resolution and require a lot of time to perform inspection.

[0006] The technique disclosed in Japanese Patent No. 6541518 is arranged to detect the presence of foreign matter sandwiched between a mold and a resist during an imprint process. Summary of the invention

[0007] The present disclosure provides a new technology related to a foreign matter inspection method for inspecting foreign matter in a substrate. Known foreign matter inspection devices (e.g., devices disclosed in Japanese Patent Publication No. 2022-29829 or Japanese Patent No. 6541518) are unable to detect foreign matter whose size is equal to or lower than the resolution limit of the imaging device (e.g., defined by the light scattering limit of the photosensitivity of the photodetector of the device (e.g., up to 70 μm or up to 500 nm)), and require a lot of time to inspect. Advantageously, the present disclosure is able to detect foreign matter (e.g., before imprinting), thereby preventing foreign matter from being included in the semiconductor structure (e.g., by preventing foreign matter from being sandwiched between the mold and the resist during the manufacturing process). In addition, the present disclosure is able to prevent the inclusion of foreign matter whose size is equal to or lower than the resolution limit of the imaging device.

[0008] One aspect of the present disclosure provides a foreign matter inspection method for inspecting foreign matter, the foreign matter inspection method comprising: bringing a first surface of a first substrate into contact with a second surface of a second substrate so that the first surface and the second surface face each other; obtaining an image of reflected light from the first surface and the second surface in contact with each other; and determining the presence, absence or location of a foreign matter based on the obtained image.

[0009] Further features of the present disclosure will become apparent from the following description of example embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 is a schematic diagram of an example foreign matter inspection device according to an embodiment.

[0011] Figure 2 is a flow chart of a foreign matter inspection method according to an embodiment.

[0012] Figure 3A and Figure 3B is a schematic diagram showing a first substrate and a second substrate in contact with each other.

[0013] Figure 4 Schematic diagram of the principle of foreign body detection.

[0014] Figure 5 Schematic diagram of the principle of interference color generation.

[0015] Fig. 6A and Figure 6B An example shape of the first substrate according to an embodiment of the present disclosure is shown.

[0016] Figure 7 An example method of bringing a first substrate into contact with a second substrate according to an embodiment of the present disclosure is shown.

[0017] Figure 8 Images captured in Example 1 are shown.

[0018] Fig. 9 The images captured in Example 2 are shown.

[0019] Fig. 10A and Fig. 10B Schematic diagram showing the difference between the area of ​​the abnormal interference color region with a liquid layer and the area of ​​the abnormal interference color region without a liquid layer.

[0020] FIG. 11A to FIG. 11F An example article manufacturing method according to an embodiment is schematically illustrated. DETAILED DESCRIPTION

[0021] The embodiments will be described in detail below in conjunction with the accompanying drawings. The following embodiments are not intended to limit the disclosure described in the appended claims. Although features are described in the embodiments, not all of these features are necessary for the disclosure. These features may be combined in any suitable manner. In addition, in the accompanying drawings, the same or similar components are assigned the same reference numerals to avoid repeated description.

[0022] Foreign matter inspection device

[0023] According to the embodiment, the foreign matter inspection device includes: a first holding unit, which is configured to hold a first substrate; a second holding unit, which is configured to hold a second substrate; a driving mechanism, which is configured to make the first surface of the first substrate contact with the second surface of the second substrate so that the first surface and the second surface face each other; a camera unit, which is configured to obtain an image of reflected light from the first surface and the second surface that are in contact with each other; and a controller, which is configured to determine the presence, absence or position of a foreign matter based on the obtained image.

[0024] Figure 1 1 is a diagram showing an example configuration of a foreign matter inspection device 1 according to an embodiment. Figure 1 The configuration of the foreign matter inspection device 1 is described. As used herein, the XY plane refers to a plane on which the second substrate 10 is disposed, and the Z direction refers to a direction orthogonal to the XY plane. Figure 1 The X-axis, Y-axis, and Z-axis defined as described above are shown.

[0025] The first substrate 8 and the second substrate 10 may be made of, for example, glass, ceramic, metal, semiconductor or resin. Each of the first substrate 8 and the second substrate 10 may have a member made of a material different from that of the substrate on its surface as required. Specific examples of the substrate include a silicon wafer, a compound semiconductor wafer and a quartz glass wafer.

[0026] The first substrate 8 may be a transparent substrate made of a light-transmitting material.

[0027] The first substrate 8 may include a mesa portion 8a having a flat top surface. The mesa portion 8a is a plateau-shaped portion having a top surface, which serves as a contact surface of the first substrate 8 to be pressed against the second substrate 10 and protrudes from its surrounding portion.

[0028] The second substrate may be made of a light-proof material.

[0029] Although at least one of the first substrate or the second substrate needs to be made of a light-transmitting material, both the first substrate and the second substrate may be light-transmitting.

[0030] Either the first substrate or the second substrate may be a substrate to be inspected for foreign matter. For example, a quartz glass wafer used for flattening and referred to as a "cover plate" may be used as the first substrate to be inspected. For example, a silicon wafer as a substrate to be nanoimprinted may be used as the second substrate to be inspected. Whether the substrate to be inspected is transparent to light or opaque to light, the substrate to be inspected may be inspected.

[0031] If the first surface of the first substrate and the second surface of the second substrate have substantially the same size, the inspection can be completed by performing the contact step described later once. If the first surface of the first substrate has a size smaller than the second surface of the second substrate, the inspection can be repeated for a plurality of areas of the second surface while the contact position between the first surface and the second surface is moving.

[0032] 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 .

[0033] The foreign matter inspection device 1 further includes a light irradiation system 2 that directs light 9 to be applied to the first and second surfaces, an imaging unit 6 that captures images of reflected light from the first and second surfaces, and a controller 7 that controls the operation of the foreign matter inspection device 1 .

[0034] The foreign matter inspection device 1 may further include: a detector 12 for detecting a mark located on the first substrate or the second substrate.

[0035] 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 at least with respect to the X-axis and the Y-axis in the XYZ coordinate system.

[0036] The second holding unit 4 includes a plurality of reference mirrors 18 in the X, Y, Z, ωx, ωy, and ωz directions on its side.

[0037] The foreign matter inspection device 1 includes a plurality of laser interferometers (measuring machines) 19 arranged in one-to-one correspondence with a plurality of reference mirrors 18 so as to apply a light beam to each reference mirror 18 to determine the position of the second holding unit 4 .

[0038] Each laser interferometer 19 measures the position of the second holding unit 4. The controller 7 performs positioning control on the second substrate 10 (or the second holding unit 4) based on the measurement value obtained at this time.

[0039] The foreign matter inspection device 1 may use an encoder instead of the reference mirror 18 and the laser interferometer 19 to determine the position of the second holding unit 4 .

[0040] The second holding unit 4 includes a substrate chuck 16 for supporting the lower surface of the second substrate 10, and the second holding unit 4 may further include a plurality of substrate chucks 16 to provide a plurality of spaces divided by the plurality of substrate chucks 16. When the first substrate is pressed against the second substrate or when the first substrate is separated from the second substrate, the pressure in each divided space may be adjusted to deform the second substrate 10.

[0041] For example, before pressing the first substrate 8 against the second substrate 10 , increasing the pressure in the space may cause the second substrate 10 to deform and protrude toward the first substrate 8 , so that the second surface of the second substrate 10 may contact the flat first surface of the first substrate 8 .

[0042] The first holding unit 3 includes a first chuck 11 holding the first substrate 8, and a first driving mechanism (actuator) 38. When the first chuck 11 is holding the first substrate 8, the first holding unit 3 is moved vertically (in the direction of the Z axis) by the first driving mechanism 38.

[0043] The first driving mechanism 38 moves the first holding unit 3 downward (in the −Z direction) so that the mesa portion 8 a (first surface) of the first substrate 8 comes into contact with the surface (second surface) of the second substrate 10 .

[0044] After the foreign matter inspection is completed, the first driving mechanism 38 moves the first holding unit 3 upward (in the +Z direction) so that the first substrate 8 is separated from the second substrate 10 .

[0045] For the contacting step and the separation, the second holding unit 4 may be moved along the Z axis instead of the first holding unit 3. The first holding unit 3 and the second holding unit 4 may be moved relative to each other.

[0046] The first holding unit 3 may further include a light-transmitting member 41 (e.g., a quartz plate) and a space 13 defined by the light-transmitting member 41 and the first substrate 8. Adjusting the pressure in the space 13 may deform the first substrate 8 during the contact step or separation. For example, increasing the pressure in the space 13 during the contact step may deform the first substrate 8 and protrude toward the second substrate 10 so that the mesa portion 8a (first surface) may contact the second surface.

[0047] The deformation at the first holding unit 3 may be controlled in combination with the deformation at the second holding unit 4 described above.

[0048] The detector 12 can detect the mark located on the first substrate 8 and the mark located on the second substrate 10 .

[0049] The foreign matter inspection device 1 can determine the relative position of the first substrate 8 and the second substrate 10 based on the detection result of the detector 12 , and align the first substrate 8 and the second substrate 10 by moving at least one of them.

[0050] The controller 7 controls the operation of the mechanism of the foreign body inspection device 1 so that the first surface contacts one or more shot regions located on the second substrate 10 and performs foreign body inspection. The controller 7 may be configured to control the first holding unit 3, the second holding unit 4, the supply unit 5, the light irradiation system 2, and the detector 12. The controller 7 may be incorporated into the foreign body inspection device 1, or may be disposed at a different location from the foreign body inspection device 1 and remotely control the foreign body inspection device 1.

[0051] The above-mentioned foreign matter inspection device 1 equipped with a supply unit 5 of a curable composition can be used as a molding device. The camera unit 6 may include a mechanism for emitting light 35. The light irradiation system 2 can emit ultraviolet light to cure the curable composition. In this case, the first holding unit 3 needs to be constructed to hold a template such as an imprinting mold with protrusions and depressions. Using the imprinting mold as a template allows the above-mentioned foreign matter inspection device to be used as a molding device (imprinting device) as follows, which forms protrusions and depressions on and in the curable composition supplied to the second substrate. Using a cover plate with a flat surface as a template held by the first holding unit 3 allows the above-mentioned foreign matter inspection device to be used as a molding device (flattening device) for flattening the surface of the second substrate.

[0052] Foreign body inspection method

[0053] Figure 2 1 is a flowchart showing the steps of an inspection process for inspecting foreign matter on the second surface of the second substrate 10 in contact with the first surface of the first substrate 8 by using the foreign matter inspection apparatus 1 .

[0054] In step 101, the second substrate 10 is loaded into the foreign matter inspection device 1. The second substrate 10 is loaded onto the substrate chuck 16 of the second holding unit 4 by a substrate conveying mechanism (not shown).

[0055] 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 the detector 12 detecting light from a mark on the first substrate 8 and light from a mark on the second substrate 10.

[0056] In step 103, the first substrate 8 and the second substrate 10 are brought close to each other so that the first surface of the first substrate 8 contacts the second surface of the second substrate 10 (contact step). At this time, there is no liquid such as imprint resist between the first surface and the second surface.

[0057] In step 104, the light irradiation system 2 applies light 9 to the first surface of the first substrate 8 and the second surface of the second substrate 10 in contact with each other (light irradiation step). The light irradiation system 2 irradiates at least the entire mesa portion 8a in contact with the second surface with light.

[0058] In step 105, images of reflected light from the first surface and the second surface are obtained to perform foreign matter inspection (image obtaining step).

[0059] In step 106 , based on the image obtained in step 105 , the presence, absence or location of a foreign object is determined.

[0060] In step 107 , the second substrate 10 is separated from the first substrate 8 (separation step).

[0061] After the second substrate 10 is separated from the first substrate 8 in step 107, it is determined in step 108 whether the foreign matter inspection process of the designated shot region on the substrate 10 is completed. If it is determined in step 108 that the foreign matter inspection process is completed, the substrate 10 is unloaded from the foreign matter inspection device 1 in step 109. If the foreign matter inspection process is not completed, the process returns to step 102. The first substrate and the second substrate are relatively moved to the next inspection position (shot region). The above steps are repeated until the foreign matter inspection process is completed.

[0062] Principle of foreign body inspection

[0063] Now refer to Figure 3A , Figure 3B and Figure 4 A foreign matter inspection principle according to an embodiment of the present disclosure is described.

[0064] Figure 3A and Figure 3Bis a schematic diagram showing a first substrate and a second substrate to be in contact with each other. Figure 3A An embodiment is shown in which the first substrate is a clean transparent substrate and the second substrate is an opaque substrate to be inspected. Figure 3B An embodiment is shown in which the first substrate is a transparent substrate to be inspected and the second substrate is a clean opaque substrate.

[0065] If there is foreign matter on the substrate to be inspected, Figure 4 As shown, a gap corresponding to the height of the foreign object is formed between the first substrate and the second substrate. The gap is the space that expands around the foreign object when at least one substrate is bent. The area with the gap will be referred to as the non-contact area. The area where the second substrate contacts the first substrate and the gap between the two is substantially zero nanometers will be referred to as the contact area.

[0066] The illumination light is irradiated through the transparent first substrate 8 or the second substrate, and reflected light is generated between the first surface of the first substrate and the second surface of the second substrate. The reflected light intensity of the contact area is different from the reflected light intensity of the non-contact area. Therefore, the presence of the non-contact area or foreign matter can be detected based on the difference in light intensity received by the camera unit.

[0067] Now refer to Figure 5 The reason why the intensity of reflected light in the contact area is different from that in the non-contact area is described. In the contact area, the illumination light is mainly reflected by the interface between the first substrate and the second substrate. In the non-contact area, since there is air in the gap between the first substrate and the second substrate, the illumination light is reflected by two different interfaces (or the interface between the first substrate and the air and the interface between the air and the second substrate). Such light beams reflected by the two interfaces interfere with each other. The degree of interference depends on the distance between the two interfaces. In other words, the intensity of the reflected light contains information about the distance between the first substrate and the second substrate or the height of the foreign matter.

[0068] This article assumes that the wavelength of the illumination light is λnm. When the distance between the first substrate and the second substrate is λ / 4, the reflected light has the minimum intensity. When the distance between the first substrate and the second substrate is λ / 2, the reflected light has the maximum intensity. For example, assuming that monochromatic light with a wavelength of 405nm is used as the illumination light, a foreign object with a height of about 101nm can be inspected as the minimum reflected light intensity area based on the captured image.

[0069] For the second substrate to be inspected, the first substrate used needs to have an optically flat inspection area surface free of foreign matter. For this reason, the first substrate can be cleaned prior to inspection to remove foreign matter. The first substrate can be inspected to determine the absence of foreign matter. The flatness of the first substrate can be inspected.

[0070] Cleaning devices, foreign matter inspection devices, and surface geometry measurement devices are available in the semiconductor industry for use in cleaning, foreign matter removal, and flatness inspection of substrates.

[0071] Cleaning devices and foreign matter inspection devices for wafer-shaped substrates or rectangular substrates with a size of 6×6×0.25 inches are widely used. For this reason, each of the first substrate and the second substrate can be a wafer-shaped substrate or a rectangular substrate with a size of 6×6×0.25 inches.

[0072] Substrate molding treatment after foreign matter inspection

[0073] After the second substrate is inspected by using the above-described foreign matter inspection method, an apparatus such as a molding apparatus or an imprint apparatus is controlled to perform molding processing such as imprinting only on an area on the second substrate determined to be free of foreign matter.

[0074] The molding process may be performed by using the molding device incorporated in the foreign matter inspection device in the above-described manner. The second substrate may be loaded into a separate imprint device and subjected to the molding process.

[0075] After the second substrate is inspected, the molding device (imprint device) may be controlled so that the molding process (imprint) is not performed on the region where the position of the foreign matter on the second substrate is determined.

[0076] After inspecting the second substrate using the foreign matter inspection method, the second substrate determined to have foreign matter larger than a predetermined size or foreign matter larger than a predetermined number may be cleaned.

[0077] The present disclosure is described below using more specific embodiments.

[0078] First embodiment

[0079] This embodiment shows an example of a first substrate. Fig. 6A As shown, the first substrate has a first surface and a second surface. The second surface has a concave portion sunken toward the first surface. The first surface has a protruding step structure. The step structure is formed in a narrow area inside the concave portion.

[0080] Fig. 6A is a schematic cross-sectional view of an example of a first substrate. Figure 6B is a schematic plan view of an example of a first substrate. Fig. 6A Shown along Figure 6B A cross section taken along line VIA-VIA in FIG.

[0081] The first substrate 110 includes a transparent substrate and has a first main surface 111 and a second main surface 112 as a first surface. The first main surface 111 has an inspection area 113. The inspection area 113 has a protruding step structure (table structure) 114, which is higher than its surrounding part. The second main surface 112 opposite to the first main surface 111 has a recess 115, which is aligned with the inspection area 113 of the first main surface, and the area of ​​the recess 115 is larger than the area of ​​the inspection area 113 of the first main surface. The above-mentioned protruding step structure is located in the central part of the substrate, and its area is less than or equal to 10% of the area of ​​the first main surface of the substrate and greater than or equal to 0.5% of the area of ​​the first main surface of the substrate.

[0082] The first substrate 110 may have a size of 6×6×0.25 inches. The first substrate 110 may be made of a highly elastic material having an elastic modulus of 50 GPa or more, particularly quartz glass. Quartz glass substrates of the above size are widely used as photomask substrates in the semiconductor industry.

[0083] Now refer to Figure 7 A method is described in which the first surface (first main surface 111) of the first substrate is brought into contact with a portion of the second surface of the second substrate, and then the contact area is expanded to the entire inspection area. The recessed portion of the first substrate is sealed, and nitrogen is supplied to the recessed portion so that the space inside the sealed recessed portion is at a pressure of, for example, 1.5 atmospheres, thereby causing the recessed portion to bend toward the second substrate ( Figure 7 [1] in the figure). The first substrate with the inspection area bent is moved downward so that the center portion of the inspection area contacts the second substrate ( Figure 7 [2] in the text). While increasing the pressure to, for example, 42 N, the outer portion of the inspection area of ​​the first substrate is gradually brought into contact with the second substrate ( Figure 7 [3] in ). When the entire inspection area is in close contact with the second substrate ( Figure 7 [4]), the pressure in the recessed portion is released to atmospheric pressure. Figure 7 In steps [2] and [3], illumination light is applied to the inspection area and an image of reflected light from the inspection area is captured, thereby detecting foreign matter in the inspection area.

[0084] Second embodiment

[0085] Will refer to Figure 1 and Figure 3A A foreign matter inspection according to a second embodiment of the present disclosure is described.

[0086] In this embodiment, if Figure 3A As shown in FIG. 1 , the second substrate which is opaque to the illumination light is the inspection object. Figure 1As shown, the first holding unit 3 holds a first substrate 8 that is transparent to the illumination light.

[0087] The first driving mechanism 38 moves the first substrate close to the opaque second substrate to make a portion of the first substrate contact the opaque second substrate, and then makes the first substrate contact the opaque second substrate to increase the contact area between the first substrate and the opaque second substrate.

[0088] Then, illumination light from the light irradiation system 2 is applied to the opaque substrate through the first substrate. The imaging unit 6 captures an image of the region sandwiched between the opaque substrate and the first substrate to obtain interference colors generated by the reflected light from the first substrate and the reflected light from the opaque substrate as an image.

[0089] When the opaque second substrate and the first substrate are in contact with each other, there is substantially no liquid such as an imprint material in the gap between the substrates. The presence of foreign matter on the opaque substrate and the position information of the foreign matter can be determined based on the interference color of the image obtained by the imaging unit 6.

[0090] Third embodiment

[0091] Will refer to Figure 1 and Figure 3B A foreign matter inspection according to a third embodiment of the present disclosure is described.

[0092] In this embodiment, if Figure 3B As shown, the first substrate transparent to the illumination light is the inspection object.

[0093] like Figure 1 As shown, the first holding unit 3 holds a first substrate 8 that is transparent to the illumination light.

[0094] The first driving mechanism 38 moves the first substrate close to the second substrate so that a portion of the first substrate contacts the second substrate, and then makes the first substrate contact the opaque second substrate to increase the contact area between the first substrate and the opaque second substrate.

[0095] Thereafter, illumination light from the light irradiation system 2 is applied to the opaque second substrate through the first substrate. The imaging unit 6 captures an image of the region sandwiched between the opaque second substrate and the first substrate to obtain interference colors generated by the reflected light from the first substrate and the reflected light from the opaque substrate as an image.

[0096] When the opaque second substrate and the first substrate are in contact with each other, substantially no liquid exists in the gap between the substrates. The presence of foreign matter on the transparent substrate and the position information of the foreign matter can be determined based on the interference color of the image obtained by the imaging unit 6 .

[0097] Example of article manufacturing

[0098] The present disclosure is also applicable to the manufacture of articles. FIG. 11A to FIG. 11F To describe the manufacture of articles according to embodiments of the present disclosure.

[0099] The patterned cured product of the curable composition formed by using a molding device can be permanently included as at least a part of any of various articles, or can be temporarily used to manufacture various articles. Examples of articles include circuit elements, optical elements, MEMS devices, recording elements, sensors, and molds. Examples of circuit elements include: volatile or non-volatile semiconductor memories, such as dynamic random access memory (DRAM), static random access memory (SRAM), flash memory, or magnetoresistive random access memory (MRAM); and semiconductor devices, such as large-scale integrated circuits (LSI), charge-coupled devices (CCD), image sensors, or field programmable gate arrays (FPGA). Examples of optical elements include diffraction gratings and polarizers. Examples of molds include imprint molds (replica molds).

[0100] The patterned cured product is directly used as a component of at least a part of the above-mentioned article, or temporarily used as a resist mask. After etching, ion implantation or any other treatment is performed in the substrate processing step, the resist mask is removed.

[0101] A specific method of manufacturing the article will now be described. Fig.11A As shown, a substrate 1z such as a silicon wafer having a material 2z to be processed such as an insulating material thereon is prepared. Then, a curable composition 3z is applied onto the surface of the material 2z by using, for example, an inkjet method. Fig.11A The curable composition 3z is shown in the form of droplets on a substrate.

[0102] like Fig. 11B As shown in FIG. 4 , an imprint mold 4z having protrusions and depressions on its surface is arranged so that the protrusions and depressions face the curable composition 3z on the substrate. Fig. 11C As shown in , the mold 4z is brought into contact with the curable composition 3z on the substrate 1z, and pressure is applied to the mold 4z. The curable composition 3z fills the gap between the mold 4z and the material 2z. When light as curing energy is irradiated to the curable composition 3z in this state through the mold 4z, the curable composition 3z is cured.

[0103] like Fig.11D As shown in , after the curable composition 3z is cured, when the mold 4z is separated from the substrate 1z, a patterned cured product of the curable composition 3z is formed on the substrate 1z. The patterned cured product is formed so that the depressions of the mold correspond to the protrusions of the cured product. In other words, the protrusions and depressions of the mold 4z are transferred to the curable composition 3z.

[0104] like Fig.11E As shown in , etching is performed using the patterned cured product as an etching resist mask to remove the portion of the surface of the material 2z without the cured product or with a thin layer of the cured product, thereby forming a groove 5z. The portion with a thin layer of the cured product can be removed in advance by using an etching different from the above etching.

[0105] like Fig.11F As shown in , by removing the patterned cured product, an article having a groove 5z on the surface of the material 2z can be provided. For example, when a silicon wafer is used as the substrate 1z, a circuit element such as a semiconductor device, a MEMS device, a recording element, or a sensor can be obtained as an article. For example, when a quartz glass wafer is used as the substrate 1z, a replica mold or an optical element can be obtained as an article.

[0106] In this embodiment, the patterned cured product is removed. After processing, the patterned cured product may remain without being removed and may be used as, for example, an insulating interlayer included in a semiconductor device, a pattern structure made of an optical material included in an optical element, or a component of an article.

[0107] Example

[0108] The present disclosure is described in more detail below using examples.

[0109] Example 1: Using a transparent first substrate to inspect an opaque second substrate in a step-and-repeat manner

[0110] The inspection object is a silicon wafer with a diameter of 300 mm. A first substrate made of quartz glass is used, and its inspection area is as follows Fig. 6A and Figure 6B As shown, the size is 26×33mm. Figure 7 As shown, an image of the inspection area is captured at a speed of 60 frames per second by using a method of bringing the first substrate into contact with the inspection object without any liquid (such as resist) therebetween. Figure 8 Images captured frame by frame are shown.

[0111] A foreign object located below the center of the inspection area was successfully detected in less than 0.25 seconds from the start of contact. Since the foreign object was surrounded by a single ring-shaped dark area, the height of the foreign object was estimated to be greater than λ / 4 and less than 3λ / 4.

[0112] Repeating the same inspection process while moving the inspection area makes it possible to perform foreign matter inspection on the entire silicon wafer having a diameter of 300 mm, for example.

[0113] Example 2: Full batch inspection of a transparent second substrate using an opaque first substrate

[0114] The inspection object is a quartz glass wafer with a diameter of 300 mm. A clean, flat silicon wafer is prepared as an opaque first substrate. The quartz glass wafer and the silicon wafer are set opposite to each other. Then the central part of the quartz glass wafer is bent toward the silicon wafer and contacts the silicon wafer. After that, the quartz glass wafer is gradually contacted with the silicon wafer from the central part of the quartz glass wafer to the edge for ten seconds. The following is taken under the condition that the wafers are completely in contact with each other. Fig. 9 The static image shown in . Therefore, a large number of foreign objects were successfully detected.

[0115] Example 3: Theoretical calculation of the non-contact area generated by foreign matter

[0116] The deformation behavior of the first substrate used in Example 1 due to a foreign object sandwiched between the substrate and the inspection object was analyzed by using the finite element analysis software program Abaqus available from Dassault Systemes. The central portion of the inspection area of ​​the first substrate made of quartz glass was brought into contact with a silicon wafer having a diameter of 300 mm, an elastic modulus of 190 GPa, and a cylindrical foreign object having a height of 0.1 μm thereon. A pressure of 42 N was applied to the first substrate in contact with the silicon wafer.

[0117] The occurrence of the non-contact area with a diameter of about 260μm around the foreign matter was calculated ( Fig. 10A ). Since interference color abnormality occurs in an area of ​​about 260 μm in diameter, which is larger than the resolution of 70 μm of the digital camera used to capture the image, the presence of foreign matter can be detected.

[0118] Comparative Example 1: Theoretical calculation of the non-contact area generated by foreign matter

[0119] The same first and second substrates as in Example 3 were used under the same foreign matter conditions as in Example 3. The deformation behavior of the first substrate with a liquid layer having a thickness of 50 nm between the first and second substrates was calculated. The first surface of the first substrate was not in direct contact with the second surface of the second substrate due to the liquid layer. The meniscus pressure generated by the liquid layer was calculated to be 1.18 MPa. The diameter of the non-contact area formed around the foreign matter was calculated to be about 11 μm ( Fig. 10B ). The non-contact area appears to be smaller than that in Example 3 because the meniscus pressure causes the first substrate to be strongly pulled toward the second substrate and the first substrate deforms to accommodate the foreign matter. The diameter of the interference color abnormal area is about 11 μm, which is smaller than the resolution of 70 μm of the digital camera used for image capture. The interference color abnormal area or foreign matter cannot be detected.

[0120] The present disclosure provides a new technology related to a foreign matter inspection method for inspecting foreign matter in a substrate.

[0121] While the present disclosure has been described with reference to exemplary embodiments, it is to be understood that the present disclosure is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

Claims

1. A foreign body inspection method for inspecting foreign bodies, the foreign body inspection method comprising: bringing the first surface of the first substrate into contact with the second surface of the second substrate so that the first surface and the second surface face each other; obtaining an image of reflected light from a first surface and a second surface in contact with each other; as well as The presence, absence, or location of a foreign object is determined based on the acquired image.

2. The foreign matter inspection method according to claim 1, wherein: The first substrate includes a light-transmitting material.

3. The foreign matter inspection method according to claim 2, further comprising: Light is applied to the first surface and the second surface through the first substrate.

4. The foreign matter inspection method according to claim 1, wherein: The contacting step includes contacting the first surface of the first substrate with the second surface of the second substrate to form a contact area where the first surface and the second surface contact each other, and a non-contact area where the first surface and the second surface do not contact each other due to foreign matter.

5. The foreign matter inspection method according to claim 4, wherein: The obtaining step includes obtaining an image of a non-contact area extending around a foreign object that bends at least one of the first surface and the second surface.

6. The foreign matter inspection method according to claim 3, wherein: The second substrate includes a material that is opaque to light.

7. The foreign matter inspection method according to claim 6, wherein: The first substrate is a substrate to be inspected.

8. The foreign matter inspection method according to claim 6, wherein: The second substrate is a substrate to be inspected.

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

10. The foreign matter inspection method according to claim 6, wherein: The second substrate is a silicon wafer.

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

12. The foreign matter inspection method according to claim 1, wherein: The size of the first surface of the first substrate is smaller than the size of the second surface of the second substrate, and a plurality of regions of the second surface are repeatedly inspected while a contact position between the first surface and the second surface is moving.

13. The foreign matter inspection method according to claim 3, wherein: Light is monochromatic.

14. A molding method, comprising: inspecting the second substrate by using the foreign matter inspection method according to claim 8; as well as The device is controlled to perform the molding process only on the area on the second substrate determined to be free of foreign matter.

15. A molding method, comprising: inspecting the second substrate by using the foreign matter inspection method according to claim 8; as well as The device is controlled to prevent the device from performing a molding process on the area on the second substrate where the position of the foreign matter is determined.

16. A molding method, comprising: inspecting the second substrate by using the foreign matter inspection method according to claim 8; as well as The second substrate is cleaned, the second substrate being determined to have foreign matter of a predetermined size or more or foreign matter of a predetermined number or more.

17. A foreign body inspection device for inspecting foreign bodies, the foreign body inspection device comprising: a first holding unit configured to hold a first substrate; a second holding unit configured to hold a second substrate; a driving mechanism configured to bring the first surface of the first substrate into contact with the second surface of the second substrate so that the first surface and the second surface face each other; an imaging unit configured to obtain an image of reflected light from the first surface and the second surface in contact with each other; as well as A controller is configured to determine the presence, absence, or location of a foreign object based on the acquired image.

18. The foreign matter inspection device according to claim 17, further comprising: The light irradiation unit is configured to apply light to the first surface and the second surface.

19. A molding device comprising: The foreign body inspection device according to claim 18; as well as a supply unit configured to supply the curable composition to the second substrate, Wherein, the first holding unit is capable of holding the template, and 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.

20. A method of manufacturing an article, comprising: forming the composition on the substrate by using the forming apparatus according to claim 19; processing the formed substrate; as well as Articles are fabricated from the treated substrate.

Images