Measurement device, measurement method, lithographic apparatus and article manufacturing method

Abstract

The present disclosure provides a measurement device that is advantageous in achieving high measurement accuracy when measuring a mark using a merging function. The measurement device includes an imaging unit that captures a mark using an imaging element, and a control unit that determines a position of the mark based on a result of a first measurement using the imaging unit and a result of a second measurement using the imaging unit performed after the first measurement. The control unit determines a first merging condition as a condition related to merging processing in the first measurement and a second merging condition as a condition related to merging processing in the second measurement based on design information of the mark (S301), sets the first merging condition (S303) and performs the first measurement (S304), and sets the second merging condition (S307) and performs the second measurement (S308).

Description

Technical Field

[0001] This invention relates to measuring devices, measuring methods, photolithography apparatus, and methods for manufacturing articles. Background Technology

[0002] For photolithography apparatuses, such as exposure units, used in photolithography processes, it is important to align the shot region on the substrate with the original image and to quickly and accurately overlay different layers onto the substrate. To shorten the measurement time during alignment, techniques have been proposed for setting up binning processing of the imaging element and measuring the position of the markers (see PTL 1). PTL 1 discloses a technique that sets up binning processing of detection signals while grouping several adjacent pixels of a plurality of pixels of the imaging element into one pixel and sequentially capturing images at predetermined intervals in a measurement area wider than the measurement field of view.

[0003] Citation List Patent documents Patent Document 1: Japanese Patent Application Publication No. 2007-142078 Summary of the Invention

[0004] Technical issues However, due to the degradation of pixel resolution, using the merging function may lead to a deterioration in the measurement accuracy of the marks formed on the substrate.

[0005] The present invention provides a measuring device that is advantageous for achieving high measurement accuracy, for example, in mark measurement using a merging function.

[0006] Problem Solution According to one aspect of the present invention, a measuring apparatus is provided, characterized in that it comprises: a camera device configured to capture an image of a mark using an imaging element; and a control unit configured to obtain the position of the mark based on the result of a first measurement using the camera device and the result of a second measurement using the camera device performed after the first measurement, wherein the control unit determines a first merging condition as a condition related to merging processing in the first measurement and a second merging condition as a condition related to merging processing in the second measurement based on design information of the mark, performs the first measurement when the first merging condition is set, and performs the second measurement when the second merging condition is set.

[0007] Advantages of the invention According to the present invention, a measuring device can be provided that is advantageous for achieving high measurement accuracy, for example, in mark measurement using a merging function.

[0008] Other features and advantages of the invention will become apparent from the following description taken in conjunction with the accompanying drawings. Note that in all the drawings, the same reference numerals denote the same or similar parts. Attached Figure Description

[0009] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0010] Figure 1A This is a diagram showing the structure of the measuring device.

[0011] Figure 1B This is a diagram showing the structure of a camera device.

[0012] Figure 2 This is a flowchart of the measurement method according to the first embodiment.

[0013] Figure 3A This is a diagram used to illustrate the merging process.

[0014] Figure 3B This is a diagram used to illustrate the merging process.

[0015] Figure 3C This is a diagram used to illustrate the merging process.

[0016] Figure 4A This is a diagram used to illustrate the measurement process according to the first embodiment.

[0017] Figure 4B This is a diagram used to illustrate the measurement process according to the first embodiment.

[0018] Figure 4C This is a diagram used to illustrate the measurement process according to the first embodiment.

[0019] Figure 4D This is a diagram used to illustrate the measurement process according to the first embodiment.

[0020] Figure 5A This is a graph showing the relationship between the merging conditions and the signal strength detected by the camera element.

[0021] Figure 5B This is a graph showing the relationship between the merging conditions and the signal strength detected by the camera element.

[0022] Figure 6 This is a flowchart of the measurement method according to the second embodiment.

[0023] Figure 7A This is a diagram used to illustrate the measurement process according to the second embodiment.

[0024] Figure 7BThis is a diagram used to illustrate the measurement process according to the second embodiment.

[0025] Figure 8 This is a flowchart of the measurement method according to the third embodiment.

[0026] Figure 9 This is a diagram used to illustrate the measurement process according to the third embodiment.

[0027] Figure 10 This is a flowchart of the measurement method according to the fourth embodiment.

[0028] Figure 11 This is a diagram illustrating the construction of the exposure apparatus according to the fifth embodiment.

[0029] Figure 12 This is a flowchart of the exposure method according to the fifth embodiment. Detailed Implementation

[0030] In the following, 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. Multiple features are described in the embodiments, but the invention is not limited to requiring all of these features, and multiple such features can be suitably combined. Furthermore, in the drawings, the same reference numerals are given the same or similar constructions, and redundant descriptions are omitted.

[0031] <First Embodiment> Figure 1A The configuration of a measuring device 100 according to an embodiment is shown. The measuring device 100 is configured to measure the position of a mark disposed on a substrate 73. The measuring device 100 includes a substrate stage WS for holding the substrate 73, a camera device 50, a control unit CU, and a user interface UI. Here, the substrate 73 is, for example, a substrate used to manufacture devices such as semiconductor devices or liquid crystal display devices. More specifically, the substrate 73 is a wafer, a glass substrate, or other substrate to be processed.

[0032] The substrate stage WS holds the substrate 73 via a substrate chuck (not shown). The substrate stage WS is connected to a stage drive mechanism (not shown). The stage drive mechanism is a positioning mechanism including a linear motor, etc., and positions the substrate 73 held on the substrate stage WS by driving the substrate stage WS in the X-axis direction, Y-axis direction, Z-axis direction, and rotational directions about each axis. The position of the substrate stage WS is monitored, for example, by a 6-axis laser interferometer IF, and under the control of the control unit CU, the substrate stage WS is driven to a predetermined position.

[0033] The control unit CU is formed, for example, by a computer (information processing device) including a CPU, memory, etc., and comprehensively controls each unit of the measuring device 100 according to the program stored in the storage unit. The control unit CU also functions as a processing unit that obtains the position of the mark 72 (measurement mark) formed on the substrate 73 by performing various types of correction processing (arithmetic processing) on ​​the measurement results obtained by the imaging device 50 (more specifically, the results of image capture of the mark 72).

[0034] The user interface (UI) may include a display device, an input device, etc. Users can specify the projection area to be set as the measurement target or the position of a mark within the projection area for multiple projection areas on the substrate 73 via the user interface (UI).

[0035] Reference Figure 1B The construction of the imaging device 50 will be described below. The imaging device 50 includes: an illumination optics system that uses light from a light source 61 to illuminate a substrate 73; and an imaging optics system that forms an image of a mark 72 formed on the substrate 73 on an imaging element 75. Light from the light source 61 is guided to an illumination aperture stop 64 via lenses 62 and 63. Light passing through the illumination aperture stop 64 is guided to a polarizing beam splitter 68 via lenses 65, a mirror 66, and a lens 67. P-polarized light passing through the beam-splitting surface of the polarizing beam splitter 68 passes through an aperture stop 69. This light is then converted into circularly polarized light by a λ / 4 plate 70 and, via an objective lens 71 arranged such that the optical axis extends along the Z direction, Köhler illuminates the measurement mark 72 formed on the substrate 73.

[0036] The light, illuminated by Köhler and reflected, diffracted, and scattered by the measuring mark 72, passes through the objective lens 71 and the λ / 4 plate 70 and is guided to the aperture stop 69. Here, the polarization state of the light from mark 72 becomes circularly polarized, opposite to the circular polarization of the light illuminating mark 72. As the light passes through the λ / 4 plate 70, it is converted from circularly polarized to S-polarized light. After passing through the aperture stop 69, the S-polarized light is reflected at the beam-splitting surface of the polarizing beam splitter 68 and guided to the imaging element 75 via the lens 74. The imaging element 75 has a signal readout unit 75a that reads the received light as an electrical signal. The signal readout unit 75a is configured to perform readout signal processing (merging processing) when grouping multiple adjacent pixels during readout. Performing merging processing can reduce the accumulation time and charge readout time due to the increase in charge capacity.

[0037] Note that the illumination optical system may be equipped with a light intensity adjustment unit (not shown) and a wavelength adjustment unit (not shown). The light intensity adjustment unit adjusts the amount of light illuminating the substrate. For example, when multiple ND filters with different transmittances to light from the light source 61 are arranged to be switchable, and the light intensity adjustment unit controls the switching of the ND filters, the intensity of the light illuminating the substrate 73 can be adjusted. Furthermore, when multiple wavelength filters (which transmit light beams with different wavelength characteristics from the light source 61) are arranged to be switchable, and the wavelength adjustment unit controls the switching of the wavelength filters, the wavelength of the light illuminating the substrate 73 can be adjusted. The wavelength adjustment unit may also include a wavelength variable element and a drive mechanism for driving the wavelength variable element. The drive mechanism includes a linear motor, etc., and the wavelength of the light illuminating the measurement mark 72 can be adjusted by driving the wavelength variable element in a predetermined direction.

[0038] Figure 1A The control unit CU obtains the position of the marker 72 based on the position information of the substrate stage WS obtained by the laser interferometer IF and the signal waveform obtained by detecting the image of the marker 72. The intensity of the signal waveform can be adjusted by at least one of the following methods: controlling the light intensity adjustment unit (ND filter) provided in the illumination optical system of the imaging device 50, controlling the output of the light source 61, and controlling the accumulation time of the imaging element 75.

[0039] Note that in the imaging optical system of the imaging device 50, a detection aperture stop can be formed by arranging multiple lenses between the polarization beam splitter 68 and the imaging element 75. Alternatively, multiple aperture stops, each capable of setting different numerical apertures relative to the illumination optical system and the imaging optical system, can be arranged in the illumination aperture stop 64 and the detection aperture stop, and these multiple aperture stops can be switchable. Thus, the σ value, a coefficient representing the ratio of the numerical aperture of the illumination system to the numerical aperture of the imaging system, can be adjusted. As a method for detecting light from the measurement mark 72, for example, dark-field detection can be used, where the apertures of the illumination aperture stop 64 and the detection aperture stop are controlled to block the 0th-order diffracted light from the measurement mark 72, thereby detecting only higher-order diffracted light and scattered light.

[0040] The following is a description of the following method: using reference Figure 1A and Figure 1B The described measuring device 100 quickly and accurately measures the position of the substrate 73 by detecting light from a mark formed on the substrate 73.

[0041] In this embodiment, the control unit CU performs the process of obtaining the position of the marker 72 based on the results of a first measurement using the camera device 50 and the results of a second measurement using the camera device 50 performed after the first measurement.

[0042] Figure 2 This is a flowchart illustrating the measurement method according to the first embodiment. The control unit CU executes the measurement method (measurement processing) by comprehensively controlling the various units of the measurement device 100.

[0043] In step S301, the control unit CU determines, based on the design information of the marker 72, the conditions related to the merging process in the first measurement (first merging condition) and the conditions related to the merging process in the second measurement (second merging condition). In this embodiment, the first measurement is a coarse measurement used to obtain the relative positional offset of the substrate 73 relative to the imaging device 50, while the second measurement is a precision measurement used to accurately obtain the position of the marker. The merging process and the method for determining the conditions related to the merging process will be described in detail later.

[0044] In step S302, the control unit CU transmits the substrate 73 to the measurement field of view of the camera device 50 by controlling the substrate stage WS.

[0045] In step S303, the control unit CU sets the first merging condition determined in step S301 for the camera element 75.

[0046] In step S304, in order to roughly measure the relative positional offset of the substrate 73 with respect to the camera device 50, the control unit CU controls the camera device 50 to capture an image of the mark 72 formed on the substrate 73.

[0047] In step S305, the control unit CU performs image processing (signal processing and arithmetic processing) on ​​the image of the mark 72 obtained by imaging in step S304. This calculates the relative position between the substrate 73 and the imaging device 50, and calculates the position correction amount for alignment between the relative positions.

[0048] In step S306, the control unit CU performs relative alignment of the substrate 73 with respect to the imaging device 50. The alignment of the substrate 73 is performed such that, for example, the X-direction of the substrate stage WS is aligned with the X-direction arrangement of the plurality of projection areas to be exposed on the substrate 73. Alternatively, the substrate 73 can be aligned such that, in the second measurement, the image of the mark 72 is positioned within the measurement area of ​​the imaging device 50. Alternatively, the alignment of the substrate 73 is not limited to the X or Y direction and can also be performed in the Z direction. For example, a coarse measurement is performed in the first measurement to obtain a relative positional offset in the Z direction, and the substrate 73 can be aligned in the Z direction in the second measurement based on the result of the first measurement to position the image of the mark 72 at the focal position of the imaging device 50.

[0049] In step S307, the control unit CU sets the second merging condition determined in step S301 for the camera element 75.

[0050] In step S308, the purpose is to accurately obtain the position of the mark, and the control unit CU controls the camera device 50 to capture an image of the mark 72 on the substrate 73.

[0051] In step S309, the control unit CU performs image processing (signal processing and arithmetic processing) on ​​the image of the mark 72 obtained by the camera in step S308. This will obtain the position information of the substrate 73 relative to the camera device 50. The position information of the substrate 73 can be obtained by measuring the positions of multiple marks 72 formed at different locations on the substrate 73.

[0052] exist Figure 2 When calculating the position of marker 72 in step S305 or S309, the position of marker 72 can be calculated by processing the image of marker 72 obtained in step S304 or S308 using, for example, a template matching method. In the template matching method, correlation processing is performed between the signal obtained in steps S304 and S308 and a pre-acquired model signal (template) so that the position exhibiting the highest correlation can be detected as the center position of the measurement pattern. Typically, the model signal (template) is represented by the relationship between the number of pixels and the signal intensity. Obtaining the centroid position of the region with several pixels on the right and left sides from the position of the peak in the correlation function can achieve a resolution of 1 / 10 pixel to 1 / 50 pixel.

[0053] Reference Figures 3A to 3C To describe the merging process in the camera element 75. Figure 3A and Figure 3BThis is a block diagram illustrating an example construction of the signal readout unit 75a in the imaging element 75. For simplicity, a 4×4 matrix is ​​used. The imaging element 75 is an image sensor that acquires image information by transferring and reading out the charge accumulated in the pixels 90. As charge transfer schemes, interline transfer type and frame transfer type are known. The frame transfer type signal readout unit 75a will be described below as an example. The frame transfer type signal readout unit 75a may include a vertical shift register 91, a horizontal shift register 92, and a sense amplifier 93. The vertical shift register 91 transfers the charge accumulated in the pixels 90 in the vertical direction. The horizontal shift register 92 sequentially transfers the charge in the horizontal direction. Then, the sense amplifier 93 reads out the signal. First, the charge accumulated below the gate electrode of each pixel of the image sensor is quickly transferred to the vertical shift register 91. Then, the vertical shift register 91 sequentially transfers the charge in the vertical direction. Assume that each pixel of the vertical shift register 91 is in the first, second, third, and fourth rows. During the transfer, the charge in the pixels of the fourth row is simultaneously transferred to the pixels of the third row, the charge in the pixels of the third row is simultaneously transferred to the pixels of the second row, the charge in the pixels of the second row is simultaneously transferred to the pixels of the first row, and the charge in the pixels of the first row is simultaneously transferred to the horizontal shift register 92.

[0054] like Figure 3A As shown, during normal charge readout, each time charge in a pixel is transferred to the horizontal shift register 92, the readout amplifier 93 operates to read the data in the horizontal shift register 92 one by one. When all data has been read, the charge transfer in each pixel is performed again. That is, the charge in the pixels of the third row is simultaneously transferred to the pixels of the second row, the charge in the pixels of the second row is simultaneously transferred to the pixels of the first row, and the charge in the pixels of the first row is simultaneously transferred to the horizontal shift register 92. Similarly, the readout amplifier 93 reads the data in the horizontal shift register 92 and repeats the charge transfer further. When all the charge initially accumulated in each pixel is transferred and read out in this way, one frame readout is completed.

[0055] like Figure 3BAs shown, merging processing in the vertical transfer direction can be performed by reading the data in the horizontal shift register 92 after several charge transfers, instead of reading the data each time a charge transfer is performed. For example, the charge in the pixels of the fourth row is simultaneously transferred to the pixels of the third row, the charge in the pixels of the third row is simultaneously transferred to the pixels of the second row, the charge in the pixels of the second row is simultaneously transferred to the pixels of the first row, and the charge in the pixels of the first row is simultaneously transferred to the horizontal shift register 92. Then, the next vertical transfer begins without reading the data in the horizontal shift register 92. That is, the charge in the pixels of the third row, the charge in the pixels of the second row, and the charge in the pixels of the first row are simultaneously and respectively transferred to the pixels of the second row, the pixels of the first row, and the horizontal shift register 92. Then, the data in the horizontal shift register 92 is read out by adding the charges in the pixels of the first row and the pixels of the second row. Reading out the photoelectric signal in this way is equivalent to using the image sensor pixel group corresponding to the pixels of the first row and the image sensor pixel group corresponding to the pixels of the second row as a single line image sensor.

[0056] As described above, the merging process can be implemented by adding and reading out the charges in multiple pixels. Through merging, multiple light-receiving sections can be provided for a single area image sensor, each configured to independently read out signals. Although a method for merging in the vertical transfer direction has been described so far, the scope of the present invention is not limited to this method. For example, controlling the readout amplifier 93 that reads out data from the horizontal shift register 92 can perform merging in the horizontal transfer direction. Furthermore, the signal readout unit 75a in the imaging element 75 can be configured to include multiple vertical shift registers, multiple horizontal shift registers, and multiple readout amplifiers. Figure 3C In the illustrated case, a vertical shift register 91A, a horizontal shift register 92A, and a sense amplifier 93A are configured for pixel group 90A, while a vertical shift register 91B, a horizontal shift register 92B, and a sense amplifier 93B are configured for pixel group 90B. For example, by setting different merging processes in multiple vertical shift registers and multiple horizontal shift registers, different merging processes can be performed on the detection surface of the imaging element.

[0057] Known methods for reducing measurement time in imaging elements typically include methods that read out pixels while decimating them on the detection surface, and methods that read out only the region of interest on the detection surface. These methods can shorten charge readout time but not accumulation time. Combining processing to shorten both the accumulation time and charge readout time caused by the increase in charge capacity is advantageous in reducing measurement time.

[0058] Although constructions for performing merging processing in an imaging element have been described so far, the scope of the invention is not limited thereto. For example, a control unit (CU) can perform merging processing on output data from the imaging element. This allows for a reduction in the noise-to-signal-strength ratio by averaging the electrical noise generated in each pixel of the imaging element.

[0059] Reference Figures 4A to 4D Describe the method for determining the merging criteria. Figure 4A A marker image 72A formed on the detection surface of an imaging element 75 is shown. The imaging element 75 can be, for example, a two-dimensional imaging element having multiple pixels in the X and Y directions. In this case, the Y direction (first direction) corresponds to the vertical transfer direction of the imaging element 75, while the X direction (second direction) corresponds to the horizontal transfer direction of the imaging element 75. The marker image 72A includes multiple line elements extending in the Y direction corresponding to the vertical transfer direction of the imaging element 75. The multiple line elements are arranged at a predetermined spacing in the X direction corresponding to the horizontal transfer direction of the imaging element 75. Figure 4A In the illustrated case, the multiple line elements (marker patterns) may include four line elements A11, A12, A13, and A14. The linewidth (length in the Y direction) of each line element is represented by L1, the spacing by P1, and the length in the Y direction corresponding to the vertical transfer direction of the imaging element 75 is represented by L2. The design information of the markers may include information related to the linewidth L1 of each line element, the spacing P1 between the line elements, and the length L2 of each line element in the Y direction.

[0060] In this embodiment, when measuring the position of the mark, the substrate is aligned by obtaining a position correction amount of the substrate transmitted to the measurement position through coarse measurement, and then a precision measurement is performed. This will accurately measure the position of the mark and obtain the position information of the substrate. Therefore, for example, a wide measurement field of view is required for coarse measurement, and high resolution is required for precision measurement. Assume that the measurement is performed to meet the requirements of a wide measurement field of view and high resolution. In this case, the charge is read out from many pixels in the imaging element 75, so a lot of time is required for readout. In addition, in order to detect the signal strength from the mark at high resolution, the accumulation time of the imaging element is increased for the purpose of obtaining a predetermined amount of detection light in each pixel, which will increase the measurement time.

[0061] Therefore, in this embodiment, the control unit CU determines the first merging condition set in the first measurement (in this embodiment, a rough measurement of the relative positional offset of the substrate 73 relative to the camera device 50) and the second merging condition set in the second measurement (in this embodiment, a precise measurement of the position of the mark 72) based on the design information of the mark 72 (S301).

[0062] Figure 4B and Figure 4C Examples of the resolutions 75W1 and 75W2 of the imaging element 75 are shown in this embodiment, where the first merging condition and the second merging condition are set in coarse measurement and fine measurement, respectively. As described above, in the merging process, the accumulated charges in a plurality of adjacent pixels that have been merged in the imaging element 75 are added together. In this embodiment, each of the first merging condition and the second merging condition may include a merging coefficient indicating the number of adjacent pixels undergoing merging. For example, if the merging coefficient is 4, it indicates that the number of adjacent pixels undergoing merging is 4. For example, if the merging coefficient is 9, it indicates that the number of adjacent pixels undergoing merging is 9.

[0063] Furthermore, the merging coefficient may include a first merging coefficient related to merging in a first direction and a second merging coefficient related to merging in a second direction. More specifically, the first merging coefficient indicates the number of adjacent pixels undergoing merging in the Y direction (first direction) corresponding to the vertical transfer direction of the imaging element 75. The second merging coefficient indicates the number of adjacent pixels undergoing merging in the X direction (second direction) corresponding to the horizontal transfer direction of the imaging element 75. The first and second merging coefficients can be set independently in the first and second measurements. Figure 4B In the coarse measurement of the first measurement shown, a 2-pixel × 2-pixel merging process is set. In this case, both the first and second merging coefficients are set to 2. Conversely, in the case of... Figure 4C In the precision measurement of the second measurement shown, a 1-pixel × 1-pixel merging process is set. In this case, "1-pixel × 1-pixel merging process" means that no merging process is set (merging is invalid). In this case, both the first merging coefficient and the second merging coefficient are set to 1. As mentioned above, the "merging condition" includes not performing merging process.

[0064] As described above, according to this embodiment, the control unit CU determines a first merging condition and a second merging condition, such that the merging coefficient specified by the first merging condition is greater than the merging coefficient specified by the second merging condition. Based on this processing, in... Figure 4B In the rough measurements shown, with Figure 4CCompared to the precision measurement shown, the measurement is performed at a lower resolution while maintaining the same measurement field of view. Therefore, in coarse measurements, the readout time can be shortened by reducing the number of pixels that read out the charge, and the measurement time can be shortened by adding charge to reduce the accumulation time.

[0065] A merging factor can be determined to reduce the resolution of the imaging element 75 in relation to the linewidth L1 of each line element constituting the marked image 72A, the spacing P1 between the line elements, and the length L2 of each line element extending in the Y direction on the detection surface of the imaging element 75. Let Ps be the pixel size of the imaging element 75 and let N be the merging factor, the merging factor N can be determined to satisfy, for example, the inequalities (1) to (3) given below: N L1 / Ps ...(1) N P1 / Ps ...(2) N L2 / Ps ...(3) As described above, since the first and second merging coefficients can be set independently, they can be set to different values ​​instead of the same value. Let Ny be the first merging coefficient indicating the number of adjacent pixels undergoing merging in the Y direction, and let Nx be the second merging coefficient indicating the number of adjacent pixels undergoing merging in the X direction. In this case, for Figure 4A The markings shown can be used to determine the first merging coefficient Ny and the second merging coefficient Nx to satisfy the inequalities (4) to (6) given below: Nx L1 / Ps ...(4) Nx P1 / Ps ...(5) Ny L2 / Ps ...(6) Furthermore, let Pi be the maximum signal strength that the imaging element 75 can detect, and let Si be the signal strength that the marker 72 can be measured with the desired accuracy (required accuracy). In this case, preferably, the merging count N is determined to satisfy, in addition to satisfying inequalities (1) to (3) or (4) to (6), also the following inequality (7): N Pi / Si ...(7) This prevents the signal strength obtained by adding the signals through merging processing from exceeding the maximum signal strength of the image sensor 75.

[0066] Figure 4DA specific example is shown of obtaining the focal position of the imaging device 50 in the Z direction and the relative positional offset of the substrate 73. The horizontal axis represents the Z position, while the vertical axis represents the signal contrast calculated based on the signal strength. For example, let Smax be the maximum signal strength of the marker image 72A detected by the imaging device 50, and Smin be the minimum signal strength, then the signal contrast SC is represented by the equation (8) given below: SC = (Smax - Smin) / (Smax + Smin) ...(8) Using this operation, for example, by detecting the signal contrast SC at different positions in the Z direction, the Z position with the highest signal contrast can be obtained as the optimal focus position of the imaging device 50. As described above, this embodiment is not limited to alignment in the X and Y directions. For example, the relative positional offset in the Z direction can be obtained in the first measurement, and the substrate 73 can be aligned in the Z direction based on the result of the first measurement in the second measurement to place the marker image 72A at the focus position of the imaging device 50.

[0067] The method for setting measurement parameters in the first and second measurements will then be described. As mentioned above, when different merging conditions are set in the first and second measurements, setting the same measurement parameters may lead to a deterioration in measurement accuracy because the output data from the imaging element 75 differs in signal strength and pixel count.

[0068] Figure 5A and Figure 5B An example is shown of the signal strength and target range of the signal strength detected by the camera element 75 when different merging conditions are set in the first and second measurements. Figure 5A and Figure 5B The examples illustrate cases where the same measurement parameters are used in both the first and second measurements, and cases where different measurement parameters are used in both measurements. If the merging coefficient in the first measurement is set to N, and the merging coefficient in the second measurement is set to 1, then according to the principle of merging processing, the signal strength becomes higher when merging is enabled (N pixels) than when merging is disabled (1 pixel). Therefore, as... Figure 5A As shown, under the same measurement parameters, it is difficult for the signal strength to fall within the target range under both the first and second merging conditions. Assuming that measurements are performed with a signal strength lower than the target signal strength, the noise-to-signal-strength ratio increases, leading to a deterioration in measurement accuracy. Adjusting the measurement parameters based on the detected signal strength to bring it within the target range increases measurement time, resulting in a decrease in productivity.

[0069] The control unit CU sets the measurement parameters in the first and second measurements so that the signal strength detected by the camera element in the first measurement (with the first merging condition set in the first measurement) and the signal strength detected by the camera element in the second measurement (with the second merging condition set in the second measurement) both fall within the target range. Figure 5B The signal strength detected is shown under different accumulation times for the imaging element 75. For example, the control unit CU sets a longer accumulation time in the second measurement than in the first measurement, based on the number of pixels added through the merging process. This setting allows the signal strength detected in the first and second measurements, respectively, with different merging conditions, to fall within a target range.

[0070] Note that the measurement parameters are not limited to the accumulation time of the imaging element 75. For example, the measurement parameters can be at least any one of the following: the gain of the imaging element 75, the amount of light adjustment (transmittance) set by the light intensity adjustment unit, the output of the light source 61, and the optical magnification of the imaging device 50. For example, the control unit CU can set at least any one of the following—the gain setting of the imaging element 75, the ND filter of the light intensity adjustment unit, and the current value of the light source 61—based on the ratio between the summed pixel counts processed by merging, so that the signal strength falls within the target range. Furthermore, the signal strength can be adjusted to fall within the target range by switching the optical magnification of the imaging device 50 between coarse and fine measurements.

[0071] In addition, such as Figure 4B and Figure 4C As shown, when different merging conditions are set in the first and second measurements, the relationship between each pixel and the signal strength in the first measurement differs from that in the second measurement because the number of pixels in the output data from the imaging element 75 is different. For example, in the merging process (2 pixels × 2 pixels), the number of pixels from the origin 70 of the imaging element 75 to the marker image 72A is reduced to half the number of pixels in the merging process (1 pixel × 1 pixel). Therefore, if the position of the marker 72 is calculated using the same model signal (template) in both the first and second measurements, the measurement accuracy deteriorates due to the difference between the number of pixels in the acquired signal and the number of pixels in the template.

[0072] Therefore, in this embodiment, the control unit CU sets different templates in the first and second measurements based on the number of pixels in the output data corresponding to the merging conditions. For example, based on the different merging conditions set for coarse and fine measurements in step S301, a template suitable for the number of pixels in each output data is set, and the coarse measurement in step S304 and the fine measurement in step S308 are performed. This prevents the degradation of the marker measurement accuracy due to the difference between the acquired signal and the number of pixels in the template.

[0073] The measurement parameter settings are not limited to a template, and at least any one of the readout area, gray level, and processing algorithm in the imaging element 75 can be set differently in the first and second measurements depending on at least any one of the required measurement time, measurement area, and measurement accuracy. For example, compared to precision measurement, the gray level detected by the imaging element 75 in coarse measurement can be reduced to reduce data volume and shorten transfer time. Furthermore, by simplifying the arithmetic processing for calculating the marker position, the operation time can be shortened. Additionally, when calculating the marker position, the control unit CU can set different processing algorithms for processing image or signal waveforms in coarse and precision measurements. Furthermore, to suppress increases in transfer time or operation time, the readout area of ​​the imaging element 75 can be reduced in precision measurement compared to coarse measurement.

[0074] Examples have been given of measuring the position of the same mark in both coarse and fine measurements, but the scope of the invention is not limited thereto. For example, marks used in both coarse and fine measurements can be: marks at different positions on the substrate, mark designs, or layers forming the marks. In this case, if the mark used in the first measurement and the mark used in the second measurement are defined as the first mark and the second mark, respectively, the control unit CU obtains the relative position information of the first mark and the second mark in advance. The control unit CU, in step S305, based on... Figure 2 The position correction amount is calculated based on the result of the first measurement performed in step S304 and the relative position information of the first and second marks. In step S306, the control unit CU aligns the second mark with the measurement area of ​​the imaging element 75.

[0075] As described above, in the first embodiment, the control unit CU determines a first merging condition and a second merging condition based on design information of markings formed on the substrate. When setting the first merging condition, the control unit CU performs a first measurement to obtain the position of the markings, obtains a position correction amount for the substrate based on the result of the first measurement, and aligns the substrate. Subsequently, when setting the second merging condition, the control unit CU performs a second measurement to obtain the position of the markings and acquires the position information of the substrate. This enables rapid and accurate measurement of the target.

[0076] <Second Embodiment> Reference Figure 6 The measurement process according to the second embodiment is described. In the first embodiment, the position correction amount is obtained by performing a coarse measurement in a first measurement. In contrast, in the second embodiment, the position information of the substrate is obtained by performing a precise measurement in both a first measurement and a second measurement with different merging conditions. Since this embodiment differs from the first embodiment in their measurement processing sequence, the measurement processing sequence will be described in detail. Other contents are the same as those in the first embodiment, and therefore their description will be omitted.

[0077] Figure 6 This is a flowchart illustrating the measurement method according to the second embodiment. The control unit CU executes the measurement method (measurement processing) by comprehensively controlling the various components of the measuring device 100.

[0078] In step S501, the control unit CU determines, based on the design information of the mark 72, conditions (first merging conditions) related to the merging process in the first measurement of the position of the mark 72 and conditions (second merging conditions) related to the merging process in the second measurement. In this embodiment, after performing a coarse measurement to obtain the relative positional offset of the substrate 73 relative to the imaging device 50, a precise measurement to accurately obtain the position of the mark is performed in the first and second measurements.

[0079] In step S502, the control unit CU controls the substrate stage WS to transfer the substrate 73 into the measurement field of view of the camera device 50. Since steps S503, S504, and S505 are related to... Figure 2 Steps S304, S305, and S306 are the same, so their description will be omitted. In step S505, the control unit CU preferably drives the substrate stage WS to align the first mark on the substrate 73 with the camera device 50.

[0080] In step S506, the control unit CU sets the first merging condition determined in step S501 for the camera element 75.

[0081] In step S507, the control unit CU controls the camera device 50 to capture an image of the first mark on the substrate 73. Thereafter, the control unit CU obtains the position of the first mark by performing image processing (signal processing and arithmetic processing) on ​​the image of the first mark obtained through imaging.

[0082] In step S508, in order to obtain the position of the second mark located at a position different from that of the first mark, the control unit CU performs alignment to position the second mark in the measurement field of view of the camera device 50.

[0083] In step S509, the control unit CU sets the second merging condition determined in step S501 for the imaging element 75. In this embodiment, the start of step S509 is not limited to a timing after the execution of step S508. For example, steps S508 and S509 can be executed simultaneously.

[0084] In step S510, the control unit CU controls the camera device 50 to capture an image of the second mark on the substrate 73. Thereafter, the control unit CU performs image processing (signal processing and arithmetic processing) on ​​the image of the second mark obtained by the camera to determine the position of the second mark.

[0085] In step S511, the control unit CU obtains the position information of the substrate 73 relative to the camera device 50 based on the position of the first mark obtained in step S507 and the position of the second mark obtained in step S510.

[0086] Reference Figure 7A and Figure 7B A method for performing precise measurement of the position of substrate 73 by using a first mark and a second mark is described. Figure 7A An image of a first mark 72B formed on the detection surface of the imaging element 75 is shown. The first mark 72B is configured as a marking pattern comprising a plurality of line elements B11, B12, B13, and B14 extending in the Y direction (first direction) corresponding to the vertical transfer direction of the imaging element 75. The plurality of line elements B11, B12, B13, and B14 are arranged at equal spacing P1, and each line element has a linewidth L1 and a length L2 in the Y direction. The first mark 72B is used to accurately measure the position of the substrate in the X direction. Figure 7B A second mark 72C formed on the detection surface of the imaging element 75 is shown. The second mark 72C is configured as a marking pattern comprising a plurality of line elements C11, C12, C13, and C14 extending in the X direction (a second direction intersecting the first direction) corresponding to the horizontal transfer direction of the imaging element 75. The plurality of line elements C11, C12, C13, and C14 are arranged at equal spacing P1, and each line element has a linewidth L1 and a length L2 in the Y direction. The second mark 72C is used to accurately measure the position of the substrate in the Y direction.

[0087] In this embodiment, the first measurement is the measurement of the first mark 72B using the camera device 50, and the second measurement is the measurement of the second mark 72C using the camera device 50. As in the first embodiment, the control unit CU determines the merging conditions in the first and second measurements based on the design information of the first mark 72B and the second mark 72C on the substrate. The method for setting the merging conditions is the same in content as the method described in the first embodiment, so its description will be omitted.

[0088] Furthermore, in this embodiment, the first merging condition includes a first merging coefficient indicating the number of adjacent pixels undergoing merging in the Y direction and a second merging coefficient indicating the number of adjacent pixels undergoing merging in the X direction. In the measurement of the first marker 72B (first measurement), merging processing of the first marker 72B in the Y direction satisfies both the requirements for a shorter measurement time accompanying the merging process and higher resolution in the measurement direction (X direction). In the measurement of the second marker 72C (second measurement), merging processing of the second marker 72C in the X direction satisfies both the requirements for a shorter measurement time accompanying the merging process and higher resolution in the measurement direction (Y direction). Therefore, in the merging processing of the first and second measurements, different conditions are set in at least one of the horizontal and vertical transfer directions of the imaging element 75.

[0089] As described above, in the second embodiment, the first merging condition and the second merging condition are determined based on the design information of the marks formed on the substrate. The positional information of the substrate is obtained by performing a first measurement of the first mark on the substrate under the first merging condition and a second measurement of the second mark on the substrate located at a position different from the first mark under the second merging condition. This enables rapid and accurate measurement of the target.

[0090] <Third Embodiment> The measurement processing according to the third embodiment will be described next. This embodiment is similar to the second embodiment in that precision measurement is performed by setting first and second measurements with different merging conditions. Since this embodiment differs from the second embodiment in their measurement processing sequence, the measurement processing sequence will be described in detail below. Other contents are the same as in the second embodiment, and therefore their description will be omitted.

[0091] Figure 8 This is a flowchart of the measurement method according to the third embodiment. The control unit CU executes the measurement method (measurement processing) by comprehensively controlling the various units of the measurement device 100.

[0092] Steps S701 to S707 and steps S708 to S710 and Figure 6Steps S501 to S507 and steps S509 to S511 are the same. In the second embodiment, after the first measurement of the first mark, the second mark located at a position different from the first mark on the substrate 73 is aligned with the imaging device 50. In contrast, in this embodiment, after the first measurement is performed in step S707, the second measurement is performed in step S709 without substrate alignment.

[0093] Reference Figure 9 A method for precisely measuring the position of a substrate 73 using a first mark and a second mark is described. Figure 9 An image of a mark 72D formed on the detection surface of the imaging element 75 is shown. The mark 72D includes a plurality of first line elements 72DX extending in the Y direction corresponding to the vertical transfer direction of the imaging element 75, and a plurality of second line elements 72DY extending in the X direction corresponding to the horizontal transfer direction of the imaging element 75. Figure 9 In the illustrated case, the plurality of first line elements 72DX include two line elements D1X and D2X for accurately measuring the position in the X direction. The plurality of second line elements 72DY include two line elements D1Y and D2Y for accurately measuring the position in the Y direction. The designation 72D is an example of a designation capable of simultaneously measuring the position in both the X and Y directions.

[0094] In this embodiment, the first measurement is a measurement of multiple first wire elements 72DX using camera device 50, while the second measurement is a measurement of multiple second wire elements 72DY using camera device 50. The control unit CU determines different merging conditions in the first measurement and the second measurement, which is a precision measurement, based on design information including the markings 72D of the multiple first wire elements 72DX and the multiple second wire elements 72DY. The method for setting the merging conditions is the same as in the second embodiment, and therefore its description will be omitted.

[0095] In this embodiment, during precision measurement, the control unit CU performs a first measurement of multiple first line elements 72DX when a first merging condition is set, and then performs a second measurement of multiple second line elements 72DY when a second merging condition is set. By performing the second measurement after the first measurement in this way without substrate alignment, the measurement time can be shortened compared to the second embodiment.

[0096] <Fourth Embodiment> The measurement processing according to the fourth embodiment will be described next. This embodiment is similar to the third embodiment in that it performs precise measurements using a first measurement and a second measurement with different merging conditions. Since this embodiment differs from the third embodiment in their measurement processing sequence, the measurement processing sequence will be described in detail below. Other contents are the same as in the third embodiment, and therefore their description will be omitted.

[0097] Figure 10 This is a flowchart of the measurement method according to the fourth embodiment. The control unit CU performs the measurement method (measurement processing) by comprehensively controlling each unit of the measurement device 100.

[0098] Steps S901 to S905 and Figure 8 Steps S701 to S705 are the same, therefore their description will be omitted. In the third embodiment, by performing separate steps... Figure 9 The multiple first line elements 72DX and multiple first line elements 72DY shown are configured with first and second measurements under different merging conditions to acquire the position information of the substrate 73. Conversely, in this embodiment, in step S906, the control unit CU respectively sets a first measurement area (wherein, for the detection surface of the imaging element 75, a first merging condition is set) and a second measurement area (wherein, a second merging condition is set). For example, the first measurement area is the measurement area of ​​the imaging element 75, which includes the ability to... Figure 9 The diagram shows multiple first line elements 72DX that are measured in the X direction, while the second measurement area is the measurement area of ​​the camera element 75, which includes multiple first line elements 72DY capable of measuring in the Y direction. In step S907, the control unit CU simultaneously measures the positions of the marks in the first and second measurement areas.

[0099] In this embodiment, the control unit CU determines different merging conditions in the first measurement and the second measurement, which is a precision measurement, based on design information including a plurality of first line elements 72DX and a plurality of first line elements 72DY, of the marker 72D. The first and second measurements are performed to simultaneously measure the position of the marker 72D in the first and second measurement areas on the detection surface of the imaging element 75. This allows for a shorter measurement time compared to the third embodiment where the second measurement is performed after the first measurement.

[0100] <Fifth Embodiment> The aforementioned measuring device can be used for the alignment of substrates in photolithography apparatuses (such as exposure apparatuses or imprinting apparatuses). An example of applying the measuring device according to this disclosure to an exposure apparatus, which is an example of a photolithography apparatus, will be described.

[0101] Figure 11This is a schematic diagram showing the arrangement of the exposure apparatus EXA. The exposure apparatus EXA is a photolithography device used in a photolithography process to form a pattern on a substrate 83, which is a manufacturing process for devices such as semiconductor devices or liquid crystal display devices. The exposure apparatus EXA exposes the substrate 83 via a mask 31, which serves as a master mask, thereby transferring the pattern of the mask 31 onto the substrate 83. In this embodiment, the exposure apparatus EXA employs a step-scan method, but a step-repetition method or other exposure methods may also be used.

[0102] like Figure 11 As shown, the exposure apparatus EXA includes an illumination optics system 801, a mask stage RS for holding the mask 31, a projection optics system 32, a substrate stage WS for holding the substrate 83, a position measuring device 550, and a control unit 1200.

[0103] The illumination optical system 801 is an optical system that uses light from the light source unit 800 to illuminate an illuminated surface. The light source unit 800 includes, for example, a laser. The laser includes an ArF excimer laser with a wavelength of about 193 nm, a KrF excimer laser with a wavelength of about 248 nm, etc., but the type of light source is not limited to an excimer laser. For example, the light source unit 800 can use an F2 laser with a wavelength of about 157 nm or extreme ultraviolet (EUV) with a wavelength of 20 nm or less as the light source.

[0104] In this embodiment, the illumination optical system 801 shapes the light from the light source unit 800 into a slit light with a predetermined shape suitable for exposure, and illuminates the mask 31. The illumination optical system 801 has the functions of uniformly illuminating the mask 31 and polarized illumination. The illumination optical system 801 includes, for example, lenses, mirrors, optical integrators, aperture stops, etc., and is formed by sequentially arranging a condenser lens, a compound eye lens, an aperture stop, a condenser lens, a slit, and an imaging optical system.

[0105] Mask 31 is formed, for example, from quartz. Mask 31 forms a pattern (circuit pattern) to be transferred to substrate 83.

[0106] The mask stage RS holds the mask 31 via a mask chuck (not shown) and is connected to a mask drive mechanism (not shown). The mask drive mechanism includes a linear motor, etc., and is capable of moving the mask 31 held by the mask stage RS by driving the mask stage RS in the X-axis direction, Y-axis direction, Z-axis direction, and rotational directions about each axis. Note that the position of the mask 31 is measured by a light oblique incidence type mask position measuring unit (not shown), and the mask 31 is positioned at a predetermined location via the mask stage RS.

[0107] The projection optical system 32 is arranged such that its optical axis extends along the Z direction and has the function of imaging light from the object plane onto the image plane. In this embodiment, the projection optical system 32 projects light (diffracted light) that has passed through the pattern of the mask 31 onto the substrate 83, thereby forming an image of the pattern of the mask 31 on the substrate. The projection optical system 32 may be an optical system formed by multiple lens elements, an optical system including multiple lens elements and at least one concave mirror (refracting optical system), or an optical system including multiple lens elements and at least one diffractive optical element (such as a Cairnal holographic lens).

[0108] A photoresist is applied to a substrate 83. The substrate 83 is the processing target onto which the pattern of the mask 31 is transferred, and may include a wafer, a liquid crystal substrate, or other types of substrate to be processed.

[0109] The substrate stage WS holds the substrate 83 via a substrate chuck (not shown) and is connected to a substrate drive mechanism (not shown). The substrate drive mechanism includes a linear motor, etc., and can move the substrate 83 held by the substrate stage WS by driving the substrate stage WS in the X-axis direction, Y-axis direction, Z-axis direction, and rotational direction about each axis. In addition, a reference plate 39 is disposed on the substrate stage WS.

[0110] The position of the substrate stage WS is monitored by, for example, a 6-axis laser interferometer 910, and can be driven synchronously with the mask stage RS via the stage control unit 1250 under the control of the control unit 1200.

[0111] The control unit 1200 is formed of a computer (information processing device) including a CPU, memory, etc., and operates the exposure apparatus EXA by comprehensively controlling the various units of the exposure apparatus EXA according to a program stored in the storage unit. The control unit 1200 controls the exposure process of transferring the pattern of the mask 31 to the substrate 83 by exposing the substrate 83 via the mask 31. Furthermore, in this embodiment, the control unit 1200 controls the measurement process in the position measuring device 550 and the correction process (calculation process) of the measurement values ​​obtained by the position measuring device 550. In this way, the control unit 1200 also functions as part of the position measuring device 550.

[0112] In the EXA exposure apparatus, light (diffracted light) that has passed through the mask 31 is projected onto the substrate 83 via the projection optics system 32. The mask 31 and the substrate 83 are arranged in an optically conjugate relationship. By scanning the mask 31 and the substrate 83 at a speed ratio that is equal to the reduction ratio of the projection optics system 32, the pattern of the mask 31 is transferred onto the substrate 83.

[0113] The position measuring device 550 is a measuring device used to measure the position of a target object. In this embodiment, the position measuring device 550 measures the position of a plurality of different marks 82 (such as alignment marks) disposed on the substrate 83. Note that the arrangement of the position measuring device 550 is similar to... Figure 1B The arrangement of the camera equipment 50 shown is omitted here.

[0114] Reference Figure 12 This section describes the sequence of exposure processes by transferring the pattern of the mask 31 onto the substrate 83 through exposure of the mask 31. As described above, the exposure process is performed by comprehensively controlling each unit of the exposure apparatus EXA via the control unit 1200.

[0115] In step S101, the substrate 83 is loaded into the exposure apparatus EXA via a transfer device (not shown). In step S102, the surface (height) of the substrate 83 is detected by a shape measuring device (not shown) to measure the surface shape of the entire substrate 83.

[0116] In step S103, calibration is performed. More specifically, the control unit 1200 drives the substrate stage WS to position the reference mark on the optical axis of the position measuring device 550 based on the designed coordinate position of the reference mark disposed on the reference plate 39 in the stage coordinate system. Then, the control unit 1200 measures the positional offset of the reference mark relative to the optical axis of the position measuring device 550 and resets the stage coordinate system based on the positional offset, such that the origin of the stage coordinate system coincides with the optical axis of the position measuring device 550. Next, the control unit 1200 drives the substrate stage WS to position the reference mark on the optical axis of the exposure light based on the designed positional relationship between the optical axis of the position measuring device 550 and the optical axis of the projection optics system 32. Then, the control unit 1200 measures the positional offset of the reference mark relative to the optical axis of the exposure light via the projection optics system 32 using a TTL (Through The Lens) measurement system.

[0117] In step S104, the control unit 1200 determines the baseline between the optical axis of the position measuring device 550 and the optical axis of the projection optical system 32 based on the calibration result obtained in step S103. In step S105, the control unit 1200 controls the position measuring device 550 to measure the position of the mark 82 disposed on the substrate 83.

[0118] In step S106, the control unit 1200 performs global alignment. More specifically, based on the measurement results obtained in step S105, the control unit 1200 calculates the offset, magnification, and rotation of the array of projection areas relative to the substrate 83, and obtains the regularity of the array of projection areas. Then, the control unit 1200 obtains correction coefficients based on the regularity and baseline of the array of projection areas, and aligns the substrate 83 with the mask 31 (exposure light) based on the correction coefficients.

[0119] In step S107, the control unit 1200 performs exposure of the substrate 83 while scanning the mask 31 and the substrate 83 along the scanning direction (Y direction). At this time, based on the surface shape of the substrate 83 measured by the shape measuring device, the control unit 1200 also performs the operation of sequentially adjusting the surface of the substrate 83 to the imaging plane of the projection optical system 32 by driving the substrate stage WS along the Z direction and the tilt direction.

[0120] In step S108, the control unit 1200 determines whether exposure of all projection areas of the substrate 83 has been completed (i.e., whether there are any unexposed projection areas). If exposure of all projection areas of the substrate 83 has not been completed, the process returns to step S107, and steps S107 and S108 are repeated until exposure of all projection areas is completed. On the other hand, if exposure of all projection areas of the substrate 83 has been completed, the process proceeds to step S109, and the substrate 83 is unloaded from the exposure apparatus EXA.

[0121] In this embodiment, the measuring device 100 according to any one of the first to fourth embodiments is applied to the exposure apparatus EXA. More specifically, the position measuring device 550 may include... Figure 1B The camera device 50 shown. For example, the control unit 1200 can implement the functions of the control unit CU described in the first to fourth embodiments.

[0122] In this embodiment, the position measuring device 550 (i.e., the camera device 50) includes multiple pixels that detect light from the mark and uses the multiple pixels to form a camera area for capturing an image of the mark. The control unit 1200 obtains the position of the mark based on the output from the camera device 50 during merging processing. The control unit 1200 performs measurement processing according to any one of the first to fourth embodiments. More specifically, the control unit 1200 determines merging conditions based on the mark's design information, and performs a first measurement to obtain the mark's position when a first merging condition is set, and performs a second measurement to obtain the mark's position when a second merging condition different from the first merging condition is set. The control unit 1200 obtains the position of the substrate based on the result of the first and second measurements or based on the result of the second measurement. This allows for accurate measurement of the target.

[0123] <Example of Article Manufacturing Method> The article manufacturing method according to embodiments of the present invention is suitable for manufacturing articles, such as micro-devices or elements having microstructures, like semiconductor devices. The article manufacturing method according to this embodiment includes the steps of transferring a pattern from a master copy onto a substrate using the aforementioned photolithography apparatus (e.g., an exposure apparatus or a plotting device), and processing the substrate on which the pattern has been transferred in the transfer step. The manufacturing method also includes other known steps (oxidation, film formation, deposition, doping, planarization, etching, resist removal, dicing, bonding, encapsulation, etc.). The article manufacturing method of this embodiment is more advantageous than conventional methods in at least one of the following aspects: article performance, quality, productivity, and production cost.

[0124] This invention is not limited to the embodiments described above, and various changes and modifications can be made within the spirit and scope of this invention. Therefore, the appended claims are made to inform the public of the scope of this invention.

[0125] This application claims priority to Japanese Patent Application No. 2023-193848, filed on November 14, 2023, the contents of which are incorporated herein by reference in their entirety. Claims (as amended under Article 19 of the Treaty) 1. A measuring device for measuring the position of a mark disposed on a substrate, the measuring device being characterized by comprising: A camera device configured to capture an image of the mark using a camera element; and The control unit is configured to obtain the position of the marker based on the results of a first measurement using the camera device and the results of a second measurement using the camera device performed after the first measurement. Specifically, the control unit determines, based on the design information of the marker, a first merging condition related to the merging process in the first measurement, and a second merging condition related to the merging process in the second measurement. The first measurement is performed when the first merging condition is set, and The second measurement is performed when the second merging condition is set. 2. The measuring device according to claim 1, characterized in that the first measurement and the second measurement are respectively a coarse measurement of the relative positional offset of the substrate relative to the imaging device and a precise measurement of the relative positional offset. The first merging condition and the second merging condition each include a merging coefficient indicating the number of adjacent pixels undergoing merging, and The control unit determines the first merging condition and the second merging condition such that the merging coefficient specified by the first merging condition becomes greater than the merging coefficient specified by the second merging condition. 3. The measuring device according to claim 2, characterized in that the mark is composed of a plurality of line elements extending in a first direction corresponding to the vertical transfer direction of the imaging element. The design information includes: information about the line width of the line elements, the spacing between the line elements, and the length of the line elements in the first direction, and On the detection surface of the camera element, let L1 be the line width, P1 be the spacing, L2 be the length, Ps be the pixel size of the camera element, and N be the merging coefficient. The control unit determines the merging coefficient specified by the first merging condition to satisfy... N L1 / Ps N P1 / Ps N L2 / Ps. 4. The measuring device according to claim 2, characterized in that the mark is composed of a plurality of line elements extending in a first direction corresponding to the vertical transfer direction of the imaging element. The design information includes: information about the line width of the line elements, the spacing between the line elements, and the length of the line elements in the first direction. The merging coefficients include a first merging coefficient and a second merging coefficient. The first merging coefficient indicates the number of adjacent pixels that undergo merging in the first direction, and the second merging coefficient indicates the number of adjacent pixels that undergo merging in a second direction corresponding to the horizontal transfer direction of the imaging element. On the detection surface of the camera element, let L1 be the line width, P1 be the spacing, L2 be the length, Ps be the pixel size of the camera element, Ny be the first merging coefficient, and Nx be the second merging coefficient. The control unit determines the first merging coefficient and the second merging coefficient specified by the first merging condition to satisfy... Nx L1 / Ps Nx P1 / Ps Ny L2 / Ps. 5. The measuring device according to claim 3, characterized in that, let Pi be the maximum signal strength detectable by the imaging element, and Si be the signal strength capable of measuring the mark with the required accuracy, the control unit determines the merging coefficient specified by the first merging condition to satisfy... N Pi / Si. 6. The measuring device according to claim 1, wherein the control unit sets a measurement parameter in the first measurement or the second measurement such that the signal strength detected by the camera element in the first measurement with the first merging condition set and the signal strength detected by the camera element in the second measurement with the second merging condition set both fall within the target range. 7. The measuring device according to claim 6, wherein the measuring parameter is the cumulative time of the imaging element. 8. The measuring device according to claim 6, characterized in that the measuring device further comprises: light source; An illumination optical system configured to illuminate the substrate with light from the light source; and A light intensity adjustment unit is configured to adjust the amount of light illuminating the substrate by the illumination optical system. The measurement parameters are at least one of the following: the cumulative time of the imaging element, the gain of the imaging element, the amount of light adjustment of the light quantity adjustment unit, the output of the light source, and the optical magnification of the imaging device. 9. The measuring apparatus according to claim 1, characterized in that the measuring apparatus further comprises: a substrate stage configured to hold and move the substrate. The control unit performs a first measurement with the first merging condition set, controls the substrate stage based on the result of the first measurement to align the substrate with the camera device, and then performs a second measurement with the second merging condition set. 10. The measuring device according to claim 1, wherein the mark comprises a first mark and a second mark, the first mark being composed of a plurality of line elements extending in a first direction corresponding to the vertical transfer direction of the imaging element, and the second mark being composed of a plurality of line elements extending in a second direction corresponding to the horizontal transfer direction of the imaging element. The first measurement and the second measurement are respectively the measurement of the first mark using the camera device and the measurement of the second mark using the camera device, and... The first merging condition and the second merging condition each include a first merging coefficient and a second merging coefficient. The first merging coefficient indicates the number of adjacent pixels that undergo merging in the first direction, and the second merging coefficient indicates the number of adjacent pixels that undergo merging in the second direction. 11. The measuring device according to claim 1, wherein the mark comprises a plurality of first line elements extending in a first direction corresponding to the vertical transfer direction of the imaging element and a plurality of second line elements extending in a second direction corresponding to the horizontal transfer direction of the imaging element. The first measurement and the second measurement are respectively measurements of the plurality of first wire elements and measurements of the plurality of second wire elements using the camera device, and... The first merging condition and the second merging condition each include a first merging coefficient and a second merging coefficient. The first merging coefficient indicates the number of adjacent pixels that undergo merging in the first direction, and the second merging coefficient indicates the number of adjacent pixels that undergo merging in the second direction. 12. The measuring device according to claim 1, characterized in that the mark comprises a plurality of first line elements extending in a first direction corresponding to the vertical transfer direction of the imaging element and a plurality of second line elements extending in a second direction corresponding to the horizontal transfer direction of the imaging element, and The control unit is configured with a first measurement area and a second measurement area. In the first measurement area, a first merging condition is set relative to the detection surface of the imaging element. In the second measurement area, a second merging condition is set relative to the detection surface. The first measurement is performed using the first measurement area to measure the plurality of first wire elements, and The second measurement is performed using the second measurement area to measure the plurality of second line elements. 13. A measurement method for measuring the position of a mark disposed on a substrate based on the result of a first measurement using a camera device configured to capture an image of the mark and the result of a second measurement using the camera device performed after the first measurement, the measurement method being characterized by comprising: Based on the design information of the marker, a first merging condition is determined as a condition related to the merging process in the first measurement, and a second merging condition is determined as a condition related to the merging process in the second measurement; The first measurement is performed when the first merging condition is set; and The second measurement is performed when the second merging condition is set. 14. A photolithography apparatus for forming a pattern on a substrate, the photolithography apparatus characterized by comprising: The measuring device according to any one of claims 1 to 12, wherein the measuring device is configured to measure the position of a mark disposed on a substrate; and A positioning mechanism is configured to position the substrate based on the position of the mark measured by the measuring device. 15. A method for manufacturing an article, characterized in that the manufacturing method comprises: Patterns are formed on a substrate using a photolithography apparatus as defined in claim 14; and Processing to form a patterned substrate, Articles are manufactured from processed substrates. 16. The measuring device according to claim 1, wherein the marking comprises a first marking and a second marking, the first marking comprising a plurality of line elements extending in a first direction, the second marking comprising a plurality of line elements extending in a second direction different from the first direction, and The control unit measures the mark by setting the merging conditions in the measurement of the first mark and the merging conditions in the measurement of the second mark to be different from each other.

Claims

1. A measuring device for measuring the position of a mark disposed on a substrate, the measuring device being characterized by comprising: A camera device configured to capture an image of the mark using a camera element; as well as The control unit is configured to obtain the position of the marker based on the results of a first measurement using the camera device and the results of a second measurement using the camera device performed after the first measurement. Specifically, the control unit determines, based on the design information of the marker, a first merging condition related to the merging process in the first measurement, and a second merging condition related to the merging process in the second measurement. The first measurement is performed when the first merging condition is set, and The second measurement is performed when the second merging condition is set.

2. The measuring device according to claim 1, characterized in that, The first measurement and the second measurement are respectively a coarse measurement of the relative positional offset of the substrate relative to the camera device and a precise measurement of the relative positional offset. The first merging condition and the second merging condition each include a merging coefficient indicating the number of adjacent pixels undergoing merging, and The control unit determines the first merging condition and the second merging condition such that the merging coefficient specified by the first merging condition becomes greater than the merging coefficient specified by the second merging condition.

3. The measuring device according to claim 2, characterized in that, The marking is composed of a plurality of line elements extending in a first direction corresponding to the vertical transfer direction of the imaging element. The design information includes: information about the line width of the line elements, the spacing between the line elements, and the length of the line elements in the first direction, and On the detection surface of the camera element, let L1 be the line width, P1 be the spacing, L2 be the length, Ps be the pixel size of the camera element, and N be the merging coefficient. The control unit determines the merging coefficient specified by the first merging condition to satisfy... N L1 / Ps N P1 / Ps N L2 / Ps.

4. The measuring device according to claim 2, characterized in that, The marking is composed of a plurality of line elements extending in a first direction corresponding to the vertical transfer direction of the imaging element. The design information includes: information about the line width of the line elements, the spacing between the line elements, and the length of the line elements in the first direction. The merging coefficients include a first merging coefficient and a second merging coefficient. The first merging coefficient indicates the number of adjacent pixels that undergo merging in the first direction, and the second merging coefficient indicates the number of adjacent pixels that undergo merging in a second direction corresponding to the horizontal transfer direction of the imaging element. On the detection surface of the camera element, let L1 be the line width, P1 be the spacing, L2 be the length, Ps be the pixel size of the camera element, Ny be the first merging coefficient, and Nx be the second merging coefficient. The control unit determines the first merging coefficient and the second merging coefficient specified by the first merging condition to satisfy... Nx L1 / Ps Nx P1 / Ps The L2 / Ps.

5. The measuring device according to claim 3, characterized in that, Let Pi be the maximum signal strength that the imaging element can detect, and Si be the signal strength that can be measured with the required accuracy for the marker. The control unit determines the combining coefficient specified by the first combining condition to satisfy... N Pi / Si.

6. The measuring device according to claim 1, characterized in that, The control unit sets measurement parameters in the first measurement or the second measurement such that the signal strength detected by the camera element in the first measurement with the first merging condition set and the signal strength detected by the camera element in the second measurement with the second merging condition set both fall within the target range.

7. The measuring device according to claim 6, characterized in that, The measurement parameter is the cumulative time of the imaging element.

8. The measuring device according to claim 6, characterized in that, The measuring device further includes: light source; An illumination optical system configured to illuminate the substrate with light from the light source; and A light intensity adjustment unit is configured to adjust the amount of light illuminating the substrate by the illumination optical system. The measurement parameters are at least one of the following: the cumulative time of the imaging element, the gain of the imaging element, the amount of light adjustment of the light quantity adjustment unit, the output of the light source, and the optical magnification of the imaging device.

9. The measuring device according to claim 1, characterized in that, The measuring device further includes a substrate stage configured to hold and move the substrate. The control unit performs a first measurement with the first merging condition set, controls the substrate stage based on the result of the first measurement to align the substrate with the camera device, and then performs a second measurement with the second merging condition set.

10. The measuring device according to claim 1, characterized in that, The marking includes a first marking and a second marking. The first marking is composed of a plurality of line elements extending in a first direction corresponding to the vertical transfer direction of the imaging element, and the second marking is composed of a plurality of line elements extending in a second direction corresponding to the horizontal transfer direction of the imaging element. The first measurement and the second measurement are respectively the measurement of the first mark using the camera device and the measurement of the second mark using the camera device, and... The first merging condition and the second merging condition each include a first merging coefficient and a second merging coefficient. The first merging coefficient indicates the number of adjacent pixels that undergo merging in the first direction, and the second merging coefficient indicates the number of adjacent pixels that undergo merging in the second direction.

11. The measuring device according to claim 1, characterized in that, The marking includes a plurality of first line elements extending in a first direction corresponding to the vertical transfer direction of the imaging element and a plurality of second line elements extending in a second direction corresponding to the horizontal transfer direction of the imaging element. The first measurement and the second measurement are respectively measurements of the plurality of first wire elements and measurements of the plurality of second wire elements using the camera device, and... The first merging condition and the second merging condition each include a first merging coefficient and a second merging coefficient. The first merging coefficient indicates the number of adjacent pixels that undergo merging in the first direction, and the second merging coefficient indicates the number of adjacent pixels that undergo merging in the second direction.

12. The measuring device according to claim 1, characterized in that, The marking includes a plurality of first line elements extending in a first direction corresponding to the vertical transfer direction of the imaging element and a plurality of second line elements extending in a second direction corresponding to the horizontal transfer direction of the imaging element. The control unit is configured with a first measurement area and a second measurement area. In the first measurement area, a first merging condition is set relative to the detection surface of the imaging element. In the second measurement area, a second merging condition is set relative to the detection surface. The first measurement is performed using the first measurement area to measure the plurality of first wire elements, and The second measurement is performed using the second measurement area to measure the plurality of second line elements.

13. A measurement method for measuring the position of a mark disposed on a substrate based on the result of a first measurement using a camera device configured to capture an image of the mark and the result of a second measurement using the camera device performed after the first measurement, the measurement method being characterized by comprising: Based on the design information of the marker, a first merging condition is determined as a condition related to the merging process in the first measurement, and a second merging condition is determined as a condition related to the merging process in the second measurement; The first measurement is performed when the first merging condition is set; as well as The second measurement is performed when the second merging condition is set.

14. A photolithography apparatus for forming a pattern on a substrate, the photolithography apparatus characterized by comprising: The measuring device as defined in any one of claims 1 to 12 is configured to measure the position of a mark disposed on a substrate; as well as A positioning mechanism is configured to position the substrate based on the position of the mark measured by the measuring device.

15. A method for manufacturing an article, characterized in that, The manufacturing method includes: Patterning is formed on a substrate using a photolithography apparatus as defined in claim 14; and Processing to form a patterned substrate, Articles are manufactured from processed substrates.

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