Mark position determination method, lithographic method, method of manufacturing article, memory medium, and lithographic apparatus

Abstract

The invention discloses a mark position determination method, a lithographic method, a method of manufacturing an article, a memory medium, and a lithographic apparatus. The method of determining a marker position includes: determining a temporary position of a marker image based on a position of the marker image on an image acquired by using a viewer capturing the image of the marker; determining a correction amount for correcting the temporary position based on a distortion map indicating a two-dimensional distribution of a distortion amount of the viewer and the marker image; and determining the position of the mark by correcting the temporary position based on the correction amount.

Description

[0001] This application is a divisional application of the Chinese invention patent application with application number 202010986241.3, application date September 18, 2020, and titled "Marking position determination method, lithography method, method for manufacturing articles, storage medium and lithography device". Technical Field

[0002] The invention relates to a method for determining a mark position, a lithography method, a method for manufacturing an article, a storage medium and a lithography apparatus. Background Art

[0003] The position of a mark set on a substrate or the like can be detected by capturing an image of the mark using a scope and processing the obtained image. If the scope has a non-negligible distortion, the distortion may affect the detection accuracy of the position of the mark. Japanese Patent Publication No. 2005-285916 discloses a method of measuring the position of a target, feeding the target to the center of the field of view of an optical system, and then measuring the position of the target again. Japanese Patent Publication No. 2006-30021 discloses a method of correcting a measured value by pre-acquiring the influence of distortion on the area of ​​the observed target.

[0004] The method disclosed in Japanese Patent Publication No. 2005-285916 requires a process of placing a target at the center of the field of view, thus extending the time required for measurement. The method disclosed in Japanese Patent Publication No. 2006-30021 cannot achieve accurate correction because the amount of influence of distortion varies depending on the shape of the marker. Summary of the invention

[0005] The present invention provides a technique that facilitates detecting the position of a marker with high accuracy.

[0006] A first aspect of the present invention provides a method for determining a marker position, the method comprising: determining a temporary position of a marker image based on the position of the marker image on an image acquired by using an observer that captures an image of the marker; determining a correction amount for correcting the temporary position based on a distortion map indicating a two-dimensional distribution of a distortion amount of the observer and the marker image; and determining the position of the marker by correcting the temporary position based on the correction amount.

[0007] A second aspect of the present invention provides a lithography method for transferring a pattern onto a substrate, the method comprising: detecting the position of a mark set on the substrate according to the mark position determination method as defined in the first aspect; and transferring the pattern to a target position on the substrate based on the position of the mark detected in the detection.

[0008] A third aspect of the present invention provides a method for manufacturing an article, the method comprising: transferring a pattern onto a substrate by the photolithography method as defined in the second aspect; processing the substrate subjected to the transfer; and obtaining an article from the substrate subjected to the processing.

[0009] A fourth aspect of the present invention provides a memory medium storing a program for causing a computer to execute the marker position determination method as defined in the first aspect.

[0010] A fifth aspect of the present invention provides a lithography apparatus, comprising an observer configured to capture an image of a mark set on a substrate and a processor configured to detect the position of the mark based on the image captured by the observer, and the lithography apparatus is configured to transfer a pattern to a target position on the substrate based on the position of the mark detected by the processor, the processor being configured to: determine a temporary position of the mark image based on the position of the mark image on an image acquired by using the observer configured to capture the image of the mark; determine a correction amount for correcting the temporary position based on a distortion map indicating a two-dimensional distribution of a distortion amount of the observer and the mark image, and determine the position of the mark by correcting the temporary position based on the correction amount.

[0011] Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a view schematically showing the arrangement of a lithography apparatus according to an embodiment of the present invention;

[0013] Figure 2 is a view showing an example of arrangement of an alignment scope;

[0014] Figure 3 is a view exemplarily showing a mark for pre-alignment;

[0015] Figure 4 is a view exemplarily showing a mark for fine alignment;

[0016] Figure 5 is a flowchart showing a process of exposing a substrate while performing alignment measurement in a first mode;

[0017] Fig. 6A and Figure 6B are flowcharts each showing a procedure for a process of exposing a substrate while performing alignment measurement in the second mode;

[0018] Fig. 7A and Figure 7B is a view used to illustrate distortion;

[0019] Figure 8 is a view exemplarily showing an area located in a peripheral portion of a field of view;

[0020] Fig. 9 is a view exemplarily showing a distortion map;

[0021] Fig.10 is a view showing a first example of a marked image;

[0022] Fig.11 is a view showing the relationship between a first example of a marker image and distortion;

[0023] Fig.12 is a view showing an amount of distortion affecting detection of a position of a first example of a marker image in the X direction;

[0024] Fig.13 is a view showing an amount of distortion affecting detection of a position of a first example of a marker image in the Y direction;

[0025] Fig.14 is a view showing a second example of a marked image;

[0026] Fig.15 is a view showing the relationship between a second example of a marker image and distortion;

[0027] Fig.16 is a view schematically illustrating a method of generating a distortion map according to a first modification example;

[0028] Fig.17 is a view schematically illustrating a method of generating a distortion map according to a second modification;

[0029] Fig.18 is a view for explaining another example of a method of determining a correction amount; and

[0030] Fig.19 is a view for explaining still another example of a method of determining a correction amount. DETAILED DESCRIPTION

[0031] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments are not intended to limit the scope of the claimed invention. A plurality of features are described in the embodiments, but the invention requiring all such features is not limited, and a plurality of such features may be appropriately combined. In addition, in the accompanying drawings, the same reference numerals are given to the same or similar configurations, and redundant descriptions thereof are omitted.

[0032] Figure 1The arrangement of a lithography apparatus 1 according to an embodiment of the present invention is schematically shown. The lithography apparatus 1 can be configured as a transfer apparatus that transfers a pattern onto a substrate 4. In this embodiment, the lithography apparatus 1 is configured as an exposure apparatus that transfers a pattern of an original plate 2 onto a substrate 4 (a photoresist film thereof), but can also be configured as an apparatus that transfers a pattern of an original plate (mold) onto an imprint material on the substrate 4.

[0033] The photolithography apparatus 1 may include a projection optical system 3, a substrate chuck 5, a substrate drive mechanism 6, an alignment scope (scope) 7, and a control unit (processor) 20. The projection optical system 3 projects the pattern of the manuscript plate 2 illuminated by the illumination optical system (not shown) onto the substrate 4. The substrate chuck 5 holds the substrate 4. The substrate 4 may have, for example, an underlying pattern and marks (alignment marks) 11 and 12 formed in a previous step, and a photoresist film arranged to cover them. The mark 11 may be a pre-alignment mark. The mark 12 may be a fine alignment mark.

[0034] The substrate driving mechanism 6 drives the substrate 4 by driving the substrate chuck 5. The alignment scope 7 includes a microscope and an image sensing device, and captures an image of a mark set on the substrate 4. The control unit 20 can detect the position of the mark on the substrate 4 based on the image captured by the alignment scope 7. In addition, the control unit 20 controls, for example, operations related to the transfer of the pattern of the manuscript plate 2 onto the substrate 4. The control unit 20 can be implemented by, for example, a PLD (abbreviation of programmable logic device) such as FPGA (abbreviation of field programmable gate array), an ASIC (abbreviation of application-specific integrated circuit), a general-purpose or special-purpose computer incorporating a program, or a combination of all or some of them. The present invention can also be implemented by a program for causing a computer to execute the method described in this specification (for example, a mark position detection method) and a memory medium (computer-readable memory medium) storing the program.

[0035] Figure 2 An example of the arrangement of the alignment scope 7 is shown. The alignment scope 7 may include, for example, a light source 8, a beam splitter 9, optical systems 10 and 13, and an image sensing device 14. Illumination light emitted from the light source 8 is reflected by the beam splitter 9, and illuminates the mark 11 (12) on the substrate 4 through the optical system 10. Diffracted light from the mark 11 enters the image sensing device 14 through the optical system 10, the beam splitter 9, and the optical system 13 to form an optical image of the mark 11 (12) on the image capturing surface of the image sensing device 14. The image sensing device 14 captures the optical image, and outputs an image (image data) including a mark image (mark image data) as an image (image data) of the mark 11. The light source 8, the beam splitter 9, the optical systems 10 and 13, and the mark 11 (12) constitute a microscope for observation.

[0036] The microscope may have a magnification that enables both pre-alignment measurement, which can search for marks in a wide range, and fine alignment measurement, which can accurately perform measurement. Generally, an arrangement using different optical systems for pre-alignment measurement and fine alignment measurement has been widely used, and thus, alignment marks having different shapes depending on such applications have been used. Figure 3 Markings 11 for pre-alignment are shown by way of example. Figure 4 A mark 12 for fine alignment is exemplarily shown. The marks 11 and 12 having shapes optimized according to the process for the wafer are generally used. Therefore, marks having various shapes are available.

[0037] The lithography apparatus 1 may have a first mode and a second mode for alignment measurement. First, a process of exposing a substrate while performing alignment measurement in the first mode will be described. Thereafter, a process of exposing a substrate while performing alignment measurement in the second mode will be described.

[0038] Figure 5 A process for exposing a substrate while performing alignment measurement in a first mode is shown. The control unit 20 controls the process. In step S101, the control unit 20 loads the substrate 4 into the lithography apparatus 1, and causes the substrate chuck 5 to hold the substrate 4. In step S102, the control unit 20 performs pre-alignment measurement. More specifically, in the pre-alignment measurement, the control unit 20 detects the position of the mark 11 used for pre-alignment by using the alignment scope 7, and roughly calculates the position of the substrate 4 based on the detection result. In this case, the position of the mark 11 is detected with respect to a plurality of shot areas on the substrate 4. This makes it possible to calculate the overall displacement and linear components (magnification and rotation) of the substrate 4.

[0039] In step S103, the control unit 20 performs placement drive based on the pre-alignment measurement result. In the placement drive, the control unit 20 causes the substrate drive mechanism 6 to drive the substrate 4 based on the pre-alignment measurement result so that the mark 12 for fine alignment falls within the center position of the field of view of the alignment scope 7. In step S104, the control unit 20 performs fine alignment measurement. More specifically, in the fine alignment measurement, the control unit 20 detects the position of the mark 12 for fine alignment by using the alignment scope 7, and detects the position of the substrate 4. The overall displacement and linear components (magnification and rotation) of the substrate 4 can be accurately calculated based on the detection results. In this case, steps S103 and S104 are repeated to detect the position of the mark 12 with respect to multiple shot areas (multiple sample shot areas) on the substrate 4. The high-order deformation components of the substrate 4 can be accurately calculated by increasing the number of marks 12 used for position detection.

[0040] In step S105, the control unit 20 aligns each shot area on the substrate 4 with the manuscript plate 2 based on the fine alignment measurement result, and exposes each shot area. Subsequently, in step S106, the control unit 20 unloads the substrate 4.

[0041] Fig. 6A and Figure 6B Each shows a procedure of a process for exposing a substrate while performing alignment measurement in the second mode. The control unit 20 controls the process. Pre-alignment measurement is not performed in the second mode. Fig. 6A An outline of the operation in the second mode is shown. Figure 6B Details of step S202 (fine alignment measurement) are shown.

[0042] In step S201, the control unit 20 loads the substrate 4 into the lithography apparatus 1, and causes the substrate chuck 5 to hold the substrate. In step S202, the control unit 20 performs fine alignment measurement. In the fine alignment measurement, the control unit 20 detects the position of the mark 12 used for fine alignment by using the alignment observer 7. The control unit 20 detects the position of the mark 12 with respect to a plurality of shot areas (a plurality of sample shot areas) on the substrate 4. In the second mode, pre-alignment measurement and placement drive are not performed, and therefore, the mark 12 is not necessarily located at the center portion of the field of view of the alignment observer 7. That is, the mark 12 may be placed at the peripheral portion of the field of view of the alignment observer 7. Therefore, the position of the image (marker image) of the mark 12 observed (captured) using the alignment observer 7 (microscope) is affected by distortion. Therefore, the control unit 20 performs processing ( Figure 6B ).

[0043] In step S203, the control unit 20 aligns each shot area on the substrate 4 with the manuscript plate 2 based on the fine alignment measurement result, and exposes each shot area. Subsequently, in step S204, the control unit 204 unloads the substrate 4.

[0044] The following will refer to Figure 6B To describe the application Fig. 6A The method for determining the position of the mark in step S202 (fine alignment measurement) in step S211 is described. In step S211, the control unit 20 captures an image of the mark 12 for fine alignment by using the alignment scope 7. With this step, an image (image data) including a mark image (marker image data) as an image (image data) of the mark 12 is acquired. In step S212 (first step), the control unit 20 determines the position of the mark image on the image acquired in step S211 as a temporary position. There is a possibility that the temporary position is an inaccurate position (a position including an error) affected by the distortion of the alignment scope 7 (microscope).

[0045] In step S213 (second step), the control unit 20 determines a correction amount for correcting the temporary position determined in step S212 based on a distortion map (described later) indicating a two-dimensional distribution of the distortion amount of the alignment scope 7 and the marker image acquired in step S211. In step S214 (third step), the control unit 20 determines the position of the marker 12 by correcting the temporary position determined in step S212 based on the correction amount determined in step S213. Note that Figure 6B The process shown in can be applied to fine alignment measurement in the first mode.

[0046] The following will describe with reference to specific examples Figure 6B The processing shown in . Fig. 7A and Figure 7B Each shows an image obtained by capturing an image of a dot chart in which dots are respectively arranged at grid elements of a square grid using the alignment scope 7 . Fig. 7A An image is shown when the alignment scope 7 is not distorted. Figure 7B An image when the alignment scope 7 has distortion is shown. When the alignment scope 7 has no distortion, the spot diagram is arranged to form a true square grid. When the alignment scope 7 has distortion, the spot diagram is distorted at the peripheral portion of the field of view of the alignment scope 7. For this reason, when the image of the mark 12 is located at the peripheral portion of the field of view of the alignment scope 7, in step S212, a position different from the position where the mark 12 actually exists is detected as a temporary position of the mark image corresponding to the mark 12.

[0047] Next, a specific description will be given of how distortion occurs at the detection position of the mark 12 when the alignment scope 7 has distortion. Figure 8 The field of view of the alignment scope 7 is shown below. Figure 8 The area 100 shown in FIG. 1 is located at the periphery of the field of view. Fig. 9 The distortion map associated with the area 100 is exemplarily shown. The distortion map indicates two-dimensional distortion of the distortion amount (the amount of displacement from the ideal position (position without any distortion)) of the alignment scope 7. In other words, the distortion map is obtained by arranging the distortion amount of the alignment scope 7 at each grid element constituting the grid.

[0048] refer to Fig. 9 , two values ​​are written in each grid element. The upper value indicates the amount of distortion in the X direction (the first distortion amount), and the lower value indicates the amount of distortion in the Y direction (the second distortion amount). In this case, the unit for providing a practical example is set to μm, but it is only an example. For example, the rightmost / uppermost grid element indicates that the amount of distortion (the amount of displacement from the ideal position) is X=+0.800μm, Y=+0.800μm. When a Fig. 9When the distortion shown in Fig.10 The position of the mark image 200 shown in FIG. 1 is detected as the center position 210 of the region 100. However, the mark on the substrate actually exists and the position corresponding to the mark image 200 is shifted from the center position 210 by an amount corresponding to the influence of the distortion amount in the grid element.

[0049] The position of the marker image is calculated based on the edge information of the marker image. The displacement of the marker image caused by the influence of the distortion in the X and Y directions can be obtained by statistically processing the distortion in multiple grid elements on the distortion map, where the distortion is related to Fig.11 . The statistical processing may be, for example, a process of obtaining an average value (e.g., an arithmetic mean). In this case, the marker image may have a first edge (an edge extending in the Y direction) crossing the X direction (the first direction) and a second edge (an edge extending in the X direction) crossing the Y direction (the second direction) orthogonal to the X direction.

[0050] Fig.12 Grid elements used to calculate the shift amount (first correction amount) of the marker image due to the distortion amount in the X direction are shown. Fig.11 The grid elements including the first edge (edge ​​extending in the Y direction) crossing the X direction (first direction) are extracted to obtain these grid elements. Based on this, in step S213, the shift amount in the X direction as the correction amount for correcting the temporary position of the mark image in the X direction can be calculated as follows:

[0051] X=(0.281+0.240+0.204+0.173+0.316+0.274+0.410+0.362+0.583+0.522+0.468+0.421) / 12

[0052] Fig.13 The grid elements used to calculate the shift amount (second correction amount) of the marker image due to the distortion amount in the Y direction are shown. Fig.11 The grid elements including the second edge (edge ​​extending in the X direction) crossing the Y direction (second direction) are extracted to obtain these grid elements. Based on this, in step S213, the shift amount in the Y direction as the correction amount for correcting the temporary position of the mark image in the Y direction can be calculated as follows:

[0053] Y=(0.421+0.468+0.522+0.583+0.362+0.410+0.274+0.316+0.173+0.204+0.240+0.281) / 12

[0054] In the above example, both the correction amount Δx in the X direction and the correction amount Δy in the Y direction are +0.355 μm. That is, when the alignment scope 7 has Figure 7B When the distortion shown in Fig.10 The position of the marker image in the captured area 100 shown in has a measured shift of +0.355 μm in the X and Y directions relative to the actual position of the corresponding marker on the substrate 4. In step S213, the temporary position of the marker image determined in step S211 is corrected based on the correction amount determined in step S212 (in the above case, Δx = +0.355 μm, and Δy = +0.355 μm). More specifically, let (x', y') be the temporary position, (x, y) be the corrected position of the marker, and (Δx, Δy) be the correction amount, the position of the marker can be calculated according to the following formula.

[0055] (x,y)=(x',y')-(Δx,Δy)

[0056] Next, detection of a mark having another shape will be described. Fig.14 When the marker image 210 shown in , the position of the marker image 201 is the center position 210 of the area 100 , which is detected as the temporary position of the marker image 201 .

[0057] In this case, if Fig.15 As shown, the shift amount of the marker image 201, that is, the correction amount can also be calculated as the average value (e.g., arithmetic mean) of the distortion amount in the grid elements where the edge of the marker image exists. In this case, the correction amount is given as (Δx, Δy) = (+0.403 μm, +0.403 μm).

[0058] Fig.10 The examples in Fig.14 The difference of the example in is the shift amount (correction amount). This indicates that even if the center position of the marker image is at the same position in the field of view of the alignment scope 7, the corresponding shift amount (correction amount) is different depending on the shape of the marker image (marker). That is, when the influence of the distortion is to be removed, it is necessary to determine the correction amount corresponding to the shape of the marker. In this embodiment, in step S213, the correction amount for correcting the temporary position determined in step S212 is determined based on the distortion map and the marker image acquired in step S211.

[0059] The distortion map can be generated by dividing the field of view of the alignment scope 7 into a plurality of grid elements and determining the amount of distortion of each grid element. Fig. 7A and Figure 7BThe image of the dot diagram shown in and the displacement amount of the position of each captured point is associated with each grid element to generate the distortion amount of each grid element. At this time, in order to minimize the influence of the measurement reproducibility of each point, the displacement amount of each point can be obtained multiple times, and the obtained displacement amounts can be averaged. The amount of distortion occurring varies depending on the wavelength of the alignment light and the illumination conditions when observing the alignment mark. Therefore, the amount of occurrence can be accurately corrected by acquiring a distortion map for each condition and selectively using the acquired distortion map. When maintenance is performed periodically or arbitrarily, the lithography apparatus 1 can perform a step of generating a distortion map at initialization. In this step, the control unit 20 can generate a distortion map based on an image obtained by capturing a dot diagram arranged with a plurality of points using the alignment observer 7.

[0060] The method for determining the correction amount is not limited to the method described above with reference to step S213. In step S212, the method for determining the correction amount can be selected according to the calculation method for determining the position of the marker image in step S212. For example, a method for determining the position of the marker image by differentiating the marker image to extract the edge portion of the marker image and calculating the center of gravity of the intensity information of the edge portion is available. When the temporary position of the marker image is determined by such a method, the correction amount can be obtained by calculating the weighted average value corresponding to the differential value in each grid element. A specific example of this method will be described below.

[0061] Fig.18 The value obtained by normalizing the differential value of the edge of the marker image crossing the X direction to 1.0 (will be referred to as the normalized differential value) is exemplarily shown. Fig.18 As exemplarily shown in FIG. , when the normalized differential value on the left side of the labeled image is different from the normalized differential value on the right side, as Fig.19 As exemplarily shown in FIG. 1 , the distortion amount in each grid element is weighted by the normalized differential value, and the weighted average value is calculated. The calculated value may be a correction amount.

[0062] According to this embodiment, the position of the mark affected by the distortion of the alignment scope 7 can be detected with high accuracy. This technique is useful especially when the pre-alignment measurement is not performed as in the second mode, that is, when the fine alignment measurement is performed in a situation where the mark may exist in the peripheral portion of the field of view of the alignment scope 7. However, it is noted that the correction of the temporary position in this embodiment can also be applied to the first mode. In this case, the position of the mark can also be detected with high accuracy.

[0063] In the first modification, the control unit 20 controls the process of generating the distortion map so as to generate the distortion map based on the image captured by using the alignment scope 7 when the dot marks are sequentially arranged at a plurality of positions in the field of view of the alignment scope 7.

[0064] Fig.16 A method for generating a distortion map according to a first variant is schematically shown. First, a substrate with a dot mark is arranged on a substrate chuck 5. Subsequently, the substrate drive mechanism 6 is operated to arrange the dot mark at an observation field position corresponding to one grid element of the distortion map. The image of the dot mark is captured by the alignment observer 7. The position of the dot mark image obtained in this way is detected. At this time, the position of the dot mark on the substrate is guaranteed by the positioning accuracy of the substrate drive mechanism 6, and the displacement amount of the position of the dot mark image with the dot mark on the substrate is the distortion amount. Subsequently, while the position of the grid element that determines the distortion amount is sequentially changed, similar processing is performed. If the driving accuracy of the substrate drive mechanism 6 is high, then because each dot mark can be moved to an almost ideal position, the displacement amount between the position of the dot mark on the substrate and the position of the dot mark image can be the distortion amount. According to the first variant, a distortion map can be generated without using any dot map in which a plurality of points are precisely arranged.

[0065] In the second modification, the control unit 20 sequentially arranges alignment marks at a plurality of positions within the field of view of the alignment scope 7, and generates a distortion map based on an image captured by using the alignment scope 7. In general, alignment marks having an arbitrary shape are used. For this reason, the alignment marks have various shapes, including alignment marks that are relatively frequently used such as standard recommended alignment marks. In such a case, as a process limited to such alignment marks, accurate correction can be achieved by generating a distortion map in the following order using the alignment marks.

[0066] Fig.17 A method for generating a distortion map according to a second variant is schematically shown. First, a substrate with a selected alignment mark can be arranged on a substrate chuck 5. Subsequently, the substrate drive mechanism 6 is operated to arrange the alignment mark at an observation field position corresponding to one grid element of the distortion map, and the alignment observer 7 captures an image of the alignment mark. The position of the alignment mark image obtained in the following manner is detected. At this time, the position of the alignment mark on the substrate is guaranteed by the positioning accuracy of the substrate drive mechanism 6, and the shift amount between the position of the alignment mark on the substrate and the aligned position is the distortion amount. Subsequently, while the position of the grid element that determines the distortion amount is sequentially changed, similar processing is performed.

[0067] According to the second variant, the distortion amount of each grid element constituting the distortion map includes a detection error unique to the shape of the alignment mark used to generate the distortion map. Therefore, when the shape of the alignment mark used for alignment measurement is similar to the shape of the alignment mark used to generate the distortion map, the distortion amount of the distortion map can be changed to a correction amount without any change. In this case, it can be determined in step S213 whether the shape of the alignment mark used for alignment measurement is similar to the shape of the alignment mark used to generate the distortion map. If the two shapes are similar to each other, the distortion amount of the distortion map can be used as a correction amount without any change. In contrast, if the two shapes are not similar to each other, the correction amount is determined according to the above embodiment. Alternatively, if it is more strictly determined that the two shapes are inconsistent with each other, the correction amount can be determined according to the above embodiment.

[0068] Alternatively, a distortion map may be prepared for each of a plurality of types of alignment marks. In this case, the distortion amount of the distortion map generated by using an alignment mark similar to the alignment mark used in alignment may be used as the correction amount.

[0069] Assume that when the position of the marker image is corrected, the center of the marker image is offset by an amount equal to or less than the size of the grid element. In this case, the correction amount can be determined by interpolation (e.g., linear interpolation) based on the distortion amount of the adjacent grids.

[0070] According to this embodiment, the position of the marker can be accurately detected by correcting the position detection result on the marker image generated by the distortion of the alignment scope 7 .

[0071] The lithography method performed by using the lithography apparatus 1 may include a detection step of detecting the position of a mark on the substrate 4 according to a mark position determination method, and a transfer step of transferring a pattern to a target position on the substrate 4 based on the position of the mark detected in the detection step.

[0072] The method of manufacturing an article according to one embodiment may include a transfer step of transferring a pattern onto a substrate 4 by a photolithography method, and a processing step of processing the substrate 4 subjected to the transfer step, and obtaining an article from the substrate 4 subjected to the processing step. The processing may include, for example, development, etching, ion implantation, and deposition.

[0073] Other embodiments

[0074] The (one or more) embodiments of the present invention may also be implemented by a computer of a system or device that reads out and executes computer executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be more completely referred to as a "non-transitory computer-readable storage medium") to perform the functions of one or more of the above (one or more) embodiments and / or includes one or more circuits (e.g., application-specific integrated circuits (ASICs)) for performing the functions of one or more of the above (one or more) embodiments, and by a method executed by a computer of a system or device, for example, by reading out and executing computer executable instructions from a storage medium to perform the functions of one or more of the above (one or more) embodiments and / or controlling one or more circuits to perform the functions of one or more of the above (one or more) embodiments. The computer may include one or more processors (e.g., a central processing unit (CPU), a microprocessing unit (MPU)), and may include a network of separate computers or separate processors to read out and execute computer executable instructions. Computer executable instructions may be provided to the computer, for example, from a network or a storage medium. The storage medium may include, for example, a hard disk, a random access memory (RAM), a read-only memory (ROM), a storage device of a distributed computing system, an optical disk (such as a compact disk (CD), a digital versatile disk (DVD), or a Blu-ray disk (BD)) TM ), one or more of flash memory devices, memory cards, etc.

[0075] Other embodiments

[0076] The embodiments of the present invention may also be implemented by providing software (program) for performing the functions of the above-described embodiments to a system or device via a network or various storage media, and a computer or a central processing unit (CPU) or a microprocessing unit (MPU) of the system or device reads and executes the program.

[0077] While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention 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 method for determining a marking position, characterized in that: include: determining a temporary position of the marker image based on a position of the marker image on an image acquired by using a scope that captures the image of the marker; determining a correction amount for correcting the temporary position based on a distortion map indicating a two-dimensional distribution of a distortion amount of the scope and the marker image; and The position of the mark is determined by correcting the temporary position based on the correction amount.

2. The method according to claim 1, wherein: In determining the correction amount, the correction amount is determined based on the distortion amount in the distortion map corresponding to the position of the edge of the marker image.

3. The method according to claim 1, wherein: The mark image has a first edge crossing a first direction and a second edge crossing a second direction orthogonal to the first direction. The distortion amount includes a first distortion amount in a first direction and a second distortion amount in a second direction, The correction amount includes a first correction amount with respect to a first direction and a second correction amount with respect to a second direction, and In determining the correction amount, a first correction amount is determined based on a first distortion amount in the distortion map corresponding to the position of the first edge, and a second correction amount is determined based on a second distortion amount in the distortion map corresponding to the position of the second edge.

4. The method according to claim 3, wherein: In determining the correction amount, a first correction amount is determined by performing statistical processing of a plurality of first distortion amounts corresponding to a plurality of positions of the first edge, and a second correction amount is determined by performing statistical processing of a plurality of second distortion amounts corresponding to a plurality of positions of the second edge.

5. The method according to claim 4, wherein: The statistical processing includes a process of obtaining an average value.

6. The method according to claim 5, wherein: The average values ​​are arithmetic means.

7. The method according to claim 5, wherein: The average is a weighted average. 8 . The method according to claim 1 , further comprising generating a distortion map based on an image obtained by capturing an image of a spot pattern in which a plurality of spots are arranged using the scope. 9 . The method of claim 1 , further comprising generating a distortion map based on an image captured by using the scope while sequentially arranging markers at a plurality of locations in a field of view of the scope.

10. The method according to claim 9, wherein: The marks are dot marks.

11. The method according to claim 9, wherein: The mark is an alignment mark.

12. A photolithography method for transferring a pattern onto a substrate, characterized in that: The method comprises: The mark position determination method defined in any one of claims 1 to 11 detects the position of a mark provided on a substrate; and The pattern is transferred to a target position on the substrate based on the position of the mark detected in the detecting.

13. A method of manufacturing an article, characterized in that The method comprises: transferring the pattern onto the substrate by the photolithography method defined in claim 12; treating the substrate subjected to the transfer; and An article is obtained from the substrate subjected to the treatment.

14. A memory medium storing a program for causing a computer to execute the marker position determination method defined in any one of claims 1 to 11.

15. A lithography apparatus, comprising an observer and a processor, wherein the observer is configured to capture an image of a mark provided on a substrate, the processor is configured to detect a position of the mark based on the image captured by the observer, and the lithography apparatus is configured to transfer a pattern to a target position on the substrate based on the position of the mark detected by the processor, The processor is configured to: determining a temporary position of the marker image based on a position of the marker image on an image acquired by using a scope configured to capture an image of the marker; determining a correction amount for correcting the temporary position based on a distortion map indicating a two-dimensional distribution of a distortion amount of the scope and the marker image; and The position of the mark is determined by correcting the temporary position based on the correction amount.

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