Measurement method, alignment method, processing method, processing apparatus, article manufacturing method, determination method, and program

Abstract

To provide a technique advantageous for measuring a mark formed on a substrate.SOLUTION: Provided is a measurement method for measuring a mark formed on a substrate in a processing apparatus that processes the substrate held by a substrate stage according to a recipe, the method including: a first step of acquiring information for designating an allowable value arbitrarily given to a processing time of the substrate held by the substrate stage; a second step of determining an additional mark to be a measurement target other than a mark designated as a measurement target by the recipe from a plurality of marks formed on the substrate based on the allowable value designated by the information acquired in the first step; and a third step of measuring a position of the mark designated as a measurement target by the recipe and a position of the additional mark determined in the second step.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a measurement method, an alignment method, a processing method, a processing device, an article manufacturing method, a determination method, and a program. [Background technology]

[0002] In recent years, with the miniaturization of electronic devices and the expansion of demand, there has been a demand for technology that can balance the miniaturization of semiconductor elements, such as memories and MPUs, with productivity. Therefore, substrate processing equipment that processes substrates used in the manufacture of semiconductor elements requires high precision in the alignment of the substrates.

[0003] In substrate alignment, a method is often used in which the position of a substrate is determined by performing pattern matching processing on image data obtained by capturing an image of a mark formed on the substrate, and related technologies have been proposed in the past (see Patent Documents 1 and 2). Patent Document 1 discloses a technology for highly accurately correcting the exposure position by combining high-order overlay parameters and low-order overlay parameters, which are obtained by changing the sampling density of substrate position information for each substrate. Patent Document 2 discloses a technology for determining a combination of the number of substrates to be sampled and the number of measurement points from a throughput model of an inspection device based on uncertainty. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 7280356 [Patent Document 2] U.S. Patent Application Publication No. 2022 / 0027437 Summary of the Invention [Problem to be solved by the invention]

[0005] However, if the density of substrate alignment measurements is uniformly controlled regardless of the production plan or the substrate processing status, it may result in an unacceptable drop in productivity or sparse measurements even when there is leeway in the production plan.

[0006] The present invention has been made in view of the above problems in the conventional technology, and has an exemplary object to provide a technique that is advantageous for measuring marks formed on a substrate. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, one aspect of the present invention provides a measurement method for measuring marks formed on a substrate in a processing apparatus that processes a substrate held by a substrate stage in accordance with a recipe, the measurement method comprising: a first step of acquiring information specifying an arbitrary tolerance value for the processing time of the substrate held by the substrate stage; a second step of determining, from a plurality of marks formed on the substrate, an additional mark to be measured in addition to the mark specified as the measurement target by the recipe, based on the tolerance value specified by the information acquired in the first step; and a third step of measuring the positions of the mark specified as the measurement target by the recipe and the positions of the additional mark determined in the second step.

[0008] Further objects and other aspects of the present invention will become apparent from the following description of the embodiments with reference to the accompanying drawings. [Effects of the Invention]

[0009] According to the present invention, for example, it is possible to provide a technique that is advantageous for measuring marks formed on a substrate. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 2 is a block diagram showing an example of a substrate transport path in the substrate processing apparatus. [Figure 2]FIG. 1 is a diagram for explaining the configuration of an exposure apparatus embodied as a substrate processing apparatus. [Figure 3] 5 is a flowchart for explaining operations related to exposure processing in the first embodiment. [Figure 4] FIG. 10 is a timing chart showing substrate transport. [Figure 5] 10 is a flowchart illustrating an example of a method for setting priorities for a plurality of marks formed on a substrate. [Figure 6] 10 is a flowchart for explaining operations related to exposure processing in the second embodiment. [Figure 7] FIG. 10 is a timing chart showing substrate transport. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims. Although multiple features are described in the embodiments, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0012] 1 is a block diagram showing an example of a substrate transport path in a substrate processing apparatus 10. The substrate processing apparatus 10 is a lithography apparatus that uses photolithography technology to form patterns on substrates and is employed in the manufacturing processes of devices such as semiconductor elements, liquid crystal display elements, and thin-film magnetic heads.

[0013] The substrate processing apparatus 10 processes a substrate held on a substrate stage according to a recipe. In this embodiment, the substrate processing apparatus 10 is embodied as an exposure apparatus that projects and transfers a pattern of an original (reticle or mask) onto a substrate such as a wafer using a projection optical system. The exposure apparatus exposes a photoresist (photosensitive agent) placed (supplied) on the substrate through the original, thereby forming a latent image corresponding to the pattern of the original in the photoresist. However, the substrate processing apparatus 10 is not limited to an exposure apparatus and may be embodied as an imprinting apparatus or a drawing apparatus. The imprinting apparatus forms a pattern of an imprinting material on the substrate by bringing an original (mold or template) into contact with the imprinting material placed on the substrate and curing the imprinting material. The drawing apparatus forms a latent image in the photoresist on the substrate by drawing a pattern on the photoresist placed on the substrate with a charged particle beam.

[0014] To balance device miniaturization with productivity, exposure tools are required to improve their fundamental performance, including resolution, overlay accuracy, and throughput. For example, because the resolution of exposure tools is inversely proportional to the numerical aperture (NA) of the projection optical system and proportional to the wavelength of the light used for exposure (exposure light), progress is being made toward increasing the NA of the projection optical system and shortening the wavelength of the exposure light. Furthermore, to improve overlay accuracy by increasing the precision of the relative alignment between the master and the substrate, techniques that control variations and changes over time in the semiconductor manufacturing process using feedforward control are known. Specific examples of such techniques include advanced equipment control (AEC) and advanced process control (APC). Furthermore, a technology is known that uses machine learning to learn from inspection results obtained by inspection tools and feeds the results forward to lithography tools and coater / developer systems.

[0015] 1, the substrate processing apparatus 10 has a carry-in station 11, transfer systems 12 and 13, an unloading station 14, and a substrate stage 200. Referring to FIG. 1, a substrate 210 is carried into the carry-in station 11 from the coating and developing apparatus 20. The substrate 210 carried into the carry-in station 11 is transferred to the substrate stage 200 by the transfer system 12. After the processing (exposure processing) on the substrate stage 200 is completed, the substrate 210 is transferred to the unloading station 14 by the transfer system 13. The substrate 210 transferred to the unloading station 14 is transferred to the coating and developing apparatus 20.

[0016] Next, with reference to Figures 2(a) and 2(b), we will explain the specific configuration of the exposure apparatus EX that is embodied as the substrate processing apparatus 10. Figure 2(a) is a diagram that schematically shows an example of the configuration of the exposure apparatus EX, and Figure 2(b) is a diagram that schematically shows an example of the configuration of a substrate alignment optical system 190 that the exposure apparatus EX has.

[0017] The exposure apparatus EX exposes a substrate 210 using a step-and-scan method or a step-and-repeat method. As shown in Figure 2(a), the exposure apparatus EX has a main control unit 100, a light source control unit 110, a light source 120, an image processing unit 130, a stage control unit 140, and an interferometer 150. Furthermore, the exposure apparatus EX has an original alignment optical system 160, an original stage 171, a projection optical system 180, a substrate alignment optical system 190, a substrate stage 200, and a control instruction unit 300.

[0018] The original stage 171 is a stage that holds and drives the original 170 illuminated by an illumination optical system (not shown). A pattern to be transferred to the substrate 210 is formed on the original 170. The projection optical system 180 is an optical system that projects the pattern of the original 170 onto the substrate 210. The substrate stage 200 is a stage that holds and drives the substrate 210.

[0019] In the exposure apparatus EX, light (exposure light) from the illumination optical system passes through the original 170 held by the original stage 171 and enters the projection optical system 180. Since the original 170 and the substrate 210 are disposed in an optically conjugate positional relationship with each other, the pattern of the original 170 is imaged and transferred via the projection optical system 180 onto the substrate 210 held by the substrate stage 200.

[0020] The original alignment optical system 160 is used to align the original 170 held by the original stage 171. The original alignment optical system 160 includes, for example, an image sensor 161 configured with an accumulation-type photoelectric conversion element, and an optical system 162 that guides light from a mark formed on the original 170 to the image sensor 161.

[0021] The substrate alignment optical system 190 is used to align the substrate 210 held by the substrate stage 200. In this embodiment, the substrate alignment optical system 190 is configured as an off-axis optical system that detects a mark 211 formed on the substrate 210.

[0022] The control instruction unit 300 is configured with an information processing device (computer) including a CPU, memory, etc. The control instruction unit 300 receives instructions from a host computer (not shown) and an operator, and acquires and manages recipes for controlling the exposure process on the substrate 210 and status information of the coating and developing apparatus 20. The control instruction unit 300 issues an operation start instruction, for example, an instruction to start lot processing, to the main controller 100 based on the recipe. The control instruction unit 300 also has the function of displaying status changes of the main controller 100 on a display unit (not shown) of the exposure apparatus EX and notifying the host computer.

[0023] The main control unit 100 is configured as an information processing device including a CPU, memory, etc. The main control unit 100 operates the exposure apparatus EX by comprehensively controlling each part of the exposure apparatus EX in accordance with a program stored in a storage unit, etc. In this embodiment, the main control unit 100 controls each part of the exposure apparatus EX to perform an exposure process for exposing the substrate 210 and other related processes.

[0024] In response to an operation start instruction from the control instruction unit 300, the main control unit 100 controls (positions) the position of the substrate stage 200 based on the positions of marks formed on the original 170 and the positions of marks formed on the substrate 210. In other words, the main control unit 100 performs alignment between the original 170 and the substrate 210, for example, global alignment.

[0025] The light source 120 includes a halogen lamp or the like, and illuminates the mark 211 formed on the substrate 210. Under the control of the main control unit 100, the light source control unit 110 controls the intensity (illumination intensity) of the light emitted from the light source 120, i.e., the light that illuminates the mark 211.

[0026] The image processing unit 130 acquires the position of the mark (mark image) by performing image processing on the image signals (detection signals) from the imaging element 161 of the original alignment optical system 160 and the imaging elements 191A and 191B of the substrate alignment optical system 190. The image processing unit 130 and the substrate alignment optical system 190 function as a measurement device that measures the position of the mark 211 formed on the substrate 210 in the exposure apparatus EX.

[0027] The interferometer 150 measures the position of the substrate stage 200 by irradiating light onto a mirror 212 provided on the substrate stage 200 and detecting the light reflected by the mirror 212. Under the control of the main controller 100, the stage controller 140 drives (controls the drive of) the substrate stage 200 to an arbitrary position based on the position of the substrate stage 200 measured by the interferometer 150.

[0028] Here, the substrate alignment optical system 190 will be described in detail with reference to Fig. 2(b). The substrate alignment optical system 190 functions as a detection unit that detects marks 211 formed on the substrate 210 and generates an image signal. As shown in Fig. 2(b), the substrate alignment optical system 190 includes image sensors 191A and 191B, imaging optical systems 192A and 192B, and a half mirror 193. The substrate alignment optical system 190 also includes an illumination optical system 194, a polarizing beam splitter 195, a relay lens 196, a λ / 4 plate 197, and an objective lens 198.

[0029] In this embodiment, light from the light source 120 is guided to a substrate alignment optical system 190 via an optical fiber (not shown) or the like. The light guided to the substrate alignment optical system 190 passes through an illumination optical system 194 and enters a polarizing beam splitter 195. The light reflected by the polarizing beam splitter 195 passes through a relay lens 196, a λ / 4 plate 197, and an objective lens 198, and illuminates a mark 211 formed on a substrate 210.

[0030] The light reflected by the mark 211 passes through an objective lens 198, a λ / 4 plate 197, a relay lens 196, and a polarizing beam splitter 195, and is incident on a half mirror 193. The light incident on the half mirror 193 is split into two beams of light at an appropriate intensity ratio, and each beam is guided to imaging optical systems 192A and 192B, which have different imaging magnifications. The imaging optical systems 192A and 192B form an image of the mark 211 on the imaging surfaces of the image sensors 191A and 191B, respectively. The image sensors 191A and 191B each include an imaging surface that captures an image of an area including the mark 211 (the image of the mark 211), and generate an image signal corresponding to the area captured on the imaging surface.

[0031] The image processing unit 130 reads out the image signals generated by the image sensors 191A and 191B. The image processing unit 130 performs image processing, in this embodiment, pattern matching processing, on the image signals read out from the image sensors 191A and 191B to acquire the position of the mark 211 on the imaging surfaces of the image sensors 191A and 191B.

[0032] Pattern matching processing is generally broadly divided into the following two types of methods. The first method is a method in which an image (grayscale image) is binarized and matched with a template prepared in advance, and the position with the highest correlation is determined as the position of the mark 211. The second method is a method in which the grayscale image (i.e., without binarizing the grayscale image) is subjected to a correlation calculation with a template containing grayscale information to determine the position of the mark 211. Note that the image processing by the image processing unit 130 is not limited to pattern matching processing, and may be any processing that can acquire (information relating to) the position of the mark 211, such as edge detection processing.

[0033] Alignment methods include a driving measurement method and an image processing method. In the driving measurement method, light (laser) is irradiated onto a mark 211 formed on a substrate 210 while the substrate stage 200 is being driven. Then, the position of the mark 211 is determined by measuring the change in intensity of the light reflected by the mark 211 and the position of the substrate stage 200 in parallel. In the image processing method, white light is irradiated onto the mark 211 formed on the substrate 210 while the substrate stage 200 is stationary. Then, the light reflected by the mark 211 is detected by a storage-type photoelectric conversion element and image processing is performed to determine the position of the mark 211.

[0034] Known alignment optical systems used in this type of alignment method include through-the-lens (TTL) optical systems, through-the-reticle (TTR) optical systems, and off-axis optical systems. TTL optical systems detect marks formed on the substrate via a projection optical system. TTR optical systems simultaneously detect marks formed on the original and the substrate via a projection optical system. Off-axis optical systems are dedicated optical systems with their optical axes located a predetermined distance away from the optical axis of the projection optical system, without using a projection optical system, and detect marks formed on the substrate by irradiating them with white light from a dedicated light source.

[0035] As described above, in this embodiment, the substrate alignment optical system 190 of the exposure apparatus EX is an off-axis optical system. In the exposure apparatus EX, two types of alignment, pre-alignment and fine alignment, are performed based on the position of the mark 211 measured by the substrate alignment optical system 190. Pre-alignment is an alignment that measures the amount of positional deviation of the substrate 210 transported from the transport system 12 to the substrate stage 200 and roughly aligns (positions) the substrate 210 so that fine alignment can be started. Fine alignment is an alignment that measures the position of the substrate 210 held by the substrate stage 200 with high precision to determine overlay parameters, and precisely aligns the substrate 210 based on these overlay parameters. The overlay parameters are parameters that represent the position of the substrate 210 held by the substrate stage 200.

[0036] Below, in each embodiment, the operation of the exposure apparatus EX, specifically the operation related to the exposure process (substrate processing), will be described.

[0037] First Embodiment FIG. 3 is a flowchart for explaining the operation relating to the exposure process of the exposure apparatus EX in the first embodiment.

[0038] In S100, the substrate 210 is carried into the carry-in station 11 from the coating and developing apparatus 20. In S101, the transfer system 12 transfers the substrate 210 carried into the carry-in station 11 to the substrate stage 200. In S102, the substrate 210 transferred from the carry-in station 11 is held by the substrate stage 200.

[0039] In S103, the main control unit 100 calculates the slack time that can be spent to measure the marks 211 formed on the substrate 210, and adds marks that can be measured within the measurable time obtained from the slack time to the measurement targets. Here, the marks to be added to the measurement targets are additional marks to be measured, in addition to the marks specified as measurement targets by the recipe, among the multiple marks 211 formed on the substrate 210. The slack time is calculated based on the difference between a tolerance (target value) arbitrarily given for the processing time of the substrate 210, which is set in the exposure tool EX, and the sum of the actual processing time of the substrate 210 and the predicted processing time of the subsequent substrate 210. The tolerance value includes a value set based on the production volume of the entire processing process of the substrate 210, and a value set based on the throughput of the exposure tool EX and other process tools (e.g., the coating and developing tool 20). The measurable time is part or all of the slack time.

[0040] In S104, mark measurement is performed. Specifically, the positions of the marks 211 formed on the substrate 210 held by the substrate stage 200, that is, the positions of the marks designated as measurement targets by the recipe, and the positions of the marks added as measurement targets in S103 are measured.

[0041] In S105, an exposure process is performed. Specifically, the pattern of the reticle 170 is projected and transferred onto the substrate 210 via the projection optical system 180 while aligning the substrate 210 (and the reticle 170) based on overlay parameters obtained from the results of the mark measurement. In this way, the exposure process includes a step (third step) of aligning the substrate 210 based on the positions of marks specified as measurement targets by the recipe and the positions of marks added as measurement targets, and a step (fourth step) of exposing the aligned substrate 210.

[0042] In S115, the main control unit 100 reevaluates measurable marks from the multiple marks 211 formed on the substrate 210, and adds the measurable marks to the measurement targets (fifth step). This is because as the exposure process, which is the processing of the substrate 210, progresses, the actual processing time (actual value) is determined and the accuracy of the measurable time obtained from the slack time improves, so it may become possible to add new marks as measurement targets. Here, the marks to be added to the measurement targets are new additional marks to be measured, other than the marks specified as measurement targets by the recipe and the marks added in S103, among the multiple marks 211 formed on the substrate 210.

[0043] In S125, the main control unit 100 determines whether or not a mark that was newly added as a measurement target in S115 exists. If a newly added mark exists, the process proceeds to S135. On the other hand, if a newly added mark does not exist, the process proceeds to S106.

[0044] In S135, the additional mark is measured (sixth step). Specifically, the position of the mark 211 formed on the substrate 210 held by the substrate stage 200, that is, the position of the mark newly added as a measurement target in S115, is measured.

[0045] In S106, the transfer system 13 transfers the substrate 210 that has been exposed in S105 from the substrate stage 200 to the unloading station 14. In S107, the substrate 210 transferred to the unloading station 14 is unloaded into the coating and developing apparatus 20.

[0046] Next, the step (S103) of adding a mark that can be measured in the measurement time obtained from the margin time to the measurement target will be described in detail with reference to Fig. 4. Fig. 4 is a diagram showing a timing chart of substrate transport in the exposure apparatus EX.

[0047] As shown in FIG. 4, for example, the n-th substrate 210 is anThe substrate is carried into the carry-in station 11 at the timing of t bn The transfer system 13 transfers the substrate 210 from the substrate stage 200 at the timing t cn In actual operation, these timings vary for each substrate depending on errors that occur in the exposure apparatus EX, the execution of calibration, the processing status of the substrate before and after, changes in the state (behavior) of the coating and developing apparatus 20, etc.

[0048] In this embodiment, t cn is the timing at which the substrate 210 is unloaded from the substrate stage 200. However, if the mark measurement (S104) for measuring the mark 211 formed on the substrate 210 and the exposure process (S105) are physically or logically separated, t cn Alternatively, the timing may be the timing at which mark measurement and exposure processing are switched over. Such a case may be, for example, when the substrate stage 200 includes at least two stages for performing mark measurement and exposure processing in parallel, that is, when the substrate stage 200 is configured as a so-called twin stage.

[0049] When the nth substrate 210 is being exposed on the substrate stage 200, the processing time for the past x (x≦−1) substrates 210 on the substrate stage 200 is expressed by the following formula.

[0050] TIFF2025118156000002.tif19124

[0051] The subscript "actual" indicates the actual value (time).

[0052] In addition, the predicted processing time (total) of the xth substrate 210 on the substrate stage 200 is bnc(n+x) (0≦x) is expressed by the following formula.

[0053] TIFF2025118156000003.tif15124

[0054] The subscript "estimated" indicates a predicted value (time).

[0055] The control instruction unit 300 determines the minimum allowable value for the processing time of y substrates 210. TIFF2025118156000004.tif1216 and maximum value TIFF2025118156000005.tif1017 is specified at least once for each value of y, and the start of lot processing is instructed. The tolerance for the processing time of the substrate 210 is a value arbitrarily given for the processing time of the substrate 210, and is determined, for example, from the recipe, control instructions from the host computer, status information of the coating and developing apparatus 20, etc. In this way, information specifying the tolerance arbitrarily given for the processing time of the substrate is acquired from the control instructions of the host computer, the recipe, etc. (first step). The tolerance for the processing time of the substrate 210 can also be rewritten (updated) during lot processing based on the recipe, control instructions from the host computer, status information of the coating and developing apparatus 20, etc. If y is 1, the tolerance is a value related to the time allowed for processing one substrate 210. In the following, the minimum tolerance for the processing time of y substrates is defined as T min , the maximum allowable value for the processing time for y substrates is T max It is sometimes written as:

[0056] where T min is determined based on the interval at which the substrate 210 is carried in from the coating and developing apparatus 20, that is, is set to a value relating to the time corresponding to the interval at which the substrate 210 is transported relative to the substrate stage 200. This makes it possible to allocate the time resulting from the difference in processing interval between the coating and developing apparatus 20 and the exposure apparatus EX to mark measurement. For example, T min By setting as shown in the following equation, the waiting time until the timing at which the subsequent substrate is transported can be used to measure the additional mark.

[0057] TIFF2025118156000006.tif1359

[0058] Furthermore, T max is determined based on the processing time of the lot, that is, is set to a value related to the time allowed for a processing unit consisting of multiple substrates. This makes it possible to measure additional marks within the processing time of the lot. Note that y is the number of substrates 210 included in one lot (the number of substrates processed in the lot), and T max may be the processing time for the lot.

[0059] The main control unit 100 min and T max Based on this, the time available for measuring the marks formed on the substrate 210 held by the substrate stage 200 is calculated.

[0060] T min The slack time m based on the evaluation of min is calculated using the following formula to ensure the minimum mark measurement time.

[0061] TIFF2025118156000007.tif43157

[0062] The maximum value is evaluated as d b(n)c(n+y-1) However, it is limited to the range of the number of sheets to be processed in the lot, lotnum, and d b(lotnum-y+1)c(lotnum) It may be in the range of up to.

[0063] Also, T max The slack time m based on the evaluation of max is calculated using the following formula to ensure the maximum mark measurement time.

[0064] TIFF2025118156000008.tif38158

[0065] Here, the predicted processing time is T min For example, the time it takes to perform the process specified by the recipe and the value of T min (time) and the longer time may be used. Also, the minimum value is evaluated by d b(n)c(n+y-1)However, it is limited to the range of the number of sheets to be processed in the lot, lotnum, and d b(lotnum-y+1)c(lotnum) It may be in the range of up to.

[0066] From these results, the margin time m is expressed by the following formula:

[0067] TIFF2025118156000009.tif1274

[0068] The main controller 100 calculates the margin time m for each exposure process of the substrate 210 on the substrate stage 200, and adds marks that can be measured within the measurable time obtained from the margin time m to the marks specified as measurement targets by the recipe, in addition to the marks specified as measurement targets by the recipe, from among the multiple marks 211 formed on the substrate 210, based on an arbitrary tolerance value given to the processing time of the substrate 210 (second process). At this time, the processing time required for performing the processing specified by the recipe is estimated based on the actual processing time of the substrate and the predicted processing time of the subsequent substrate (estimation process). Then, the margin time is calculated based on the tolerance value and the estimated processing time (calculation process), and the additional marks to be measured are determined based on the measurable time obtained from the margin time (determination process). For example, the number of marks that can be measured within the measurable time (all or part of the margin time) is determined as the additional marks. The measurement results of these marks are used to calculate overlay parameters and detect abnormalities by detecting outliers.

[0069] Furthermore, the measurement results of the additional mark measurement (S135) (positions of marks newly added as measurement targets) are not used for aligning the substrate 210. The measurement results of the additional mark measurement are used in the process (seventh process) of learning a model (mathematical model) for deriving overlay parameters for the subsequent substrate. Note that in the model learning process, the measurement results of the mark measurement (S104), in particular, the measurement results of marks added as measurement targets other than marks specified as measurement targets by the recipe, may be used.

[0070] The marks to be added as measurement targets are selected (determined) in descending order of priority from the marks 211 formed on the substrate 210. The priority should be set to increase as the degree of variation in the measurement results of the position of the mark 211 increases, that is, as the uncertainty regarding the measurement of the mark 211 increases. In other words, it is preferable to preferentially select marks with high uncertainty as marks to be added as measurement targets. By actually measuring marks with high uncertainty, it is possible to eliminate the uncertainty, improving alignment accuracy and model-based prediction accuracy.

[0071] An example of a method for setting priorities for each of the multiple marks 211 formed on the substrate 210 will be described with reference to FIG.

[0072] In S200, one mark (initial mark) is selected from the plurality of marks 211 formed on the substrate 210. In S201, a predicted value of the measurement result of the mark 211 over the entire surface of the substrate 210 is calculated based on the measurement result of the mark selected in S200 and a model. In S202, the substrate 210 is aligned based on overlay parameters obtained from the predicted value calculated in S201, and the positional deviation of the substrate 210 from the ideal position, i.e., the correction residual, is calculated. In S203, it is determined whether all of the marks 211 formed on the substrate 210 have been selected. If all of the marks 211 have not been selected, the process proceeds to S200 to select the next mark 211. On the other hand, if all of the marks 211 have been selected, the process proceeds to S204. In S204, a higher priority is set among the plurality of marks 211 formed on the substrate 210, starting with the mark having the largest correction residual calculated in S203.

[0073] In this way, by setting priorities for each of the multiple marks 211 formed on the substrate 210, it becomes possible to select (determine) marks to be added as measurement targets in descending order of priority.

[0074] According to this embodiment, it is possible to dynamically control the precision of measurements related to the alignment of the substrate 210 depending on the production plan of the substrate processing apparatus 10 and the processing status of the substrate 210, thereby providing an advantageous technique for aligning the substrate 210.

[0075] Second Embodiment 6 is a flowchart for explaining the operation related to the exposure process of the exposure apparatus EX in the second embodiment. Note that S100, S101, S102, S104 to S107, S115, S125, and S135 are the same as in the first embodiment, and therefore detailed explanations thereof will be omitted here.

[0076] In S301, in addition to the surplus time, the transport time from when the substrate held by the substrate stage 200 is removed until the subsequent substrate is brought in, i.e., the transport waiting time, is calculated, and marks that can be measured within the measurable time obtained from these times are added to the measurement targets.

[0077] The step (S301) of adding a mark that can be measured in the measurement time obtained from the slack time and transport wait time to the measurement target will be described in detail with reference to Fig. 7. Fig. 7 is a diagram showing a timing chart of substrate transport in the exposure apparatus EX.

[0078] As shown in FIG. 7, depending on the state of the coating and developing apparatus 20 and the operation of the transfer system 12, the timing at which the exposure process of the first substrate 210 on the substrate stage 200 is completed is t c1 In this case, the transfer of the second substrate 210 may not be completed. In this case, when the first substrate 210 is carried out from the substrate stage 200 to the carry-out station 14, the second substrate 210 is not immediately carried to the substrate stage 200, and a transfer wait time occurs. This transfer wait time is expressed by the following equation.

[0079] TIFF2025118156000010.tif1392

[0080] Such transport wait time is used to measure additional marks to be measured in addition to the marks specified as measurement targets by the recipe. Specifically, in this embodiment, the additional marks to be measured in addition to the marks specified as measurement targets by the recipe are determined based on either the slack time or the transport wait time. For example, the slack time and the transport wait time are compared, and the additional marks to be measured are determined based on the longer of these. In other words, if the transport wait time is longer than the slack time, the slack time is replaced with the transport wait time, making it possible to determine the additional marks to be measured based on the measurable time obtained from the transport wait time.

[0081] As described above, in this embodiment, the processing time required for performing the processing specified by the recipe is estimated based on the actual processing time of the substrate and the predicted processing time of the subsequent substrate (first estimation process). Then, the slack time is calculated based on the tolerance and the estimated processing time (calculation process). Also, the transport time from when the substrate held by the substrate stage 200 is unloaded until the subsequent substrate is loaded is estimated (second estimation process). Then, based on either the slack time or the transport time, an additional mark to be measured is determined (determination process).

[0082] The method for manufacturing an article according to an embodiment of the present invention is suitable for manufacturing articles such as devices (semiconductor elements, magnetic storage media, liquid crystal display elements, etc.). This manufacturing method includes the steps of forming a pattern on a substrate using a substrate processing apparatus 10 (exposure apparatus EX), processing the substrate on which the pattern has been formed, and manufacturing an article from the processed substrate. This manufacturing method may also include other well-known steps (oxidation, film formation, vapor deposition, doping, planarization, etching, resist stripping, dicing, bonding, packaging, etc.). The method for manufacturing an article according to this embodiment is advantageous over conventional methods in at least one of the performance, quality, productivity, and production cost of the article.

[0083] The present invention can also be realized by supplying a program that implements one or more of the functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program.The present invention can also be realized by a circuit (e.g., ASIC) that implements one or more of the functions.

[0084] The disclosure of this specification includes the following alignment method, processing method, processing device, article manufacturing method, determination method, and program.

[0085] (Item 1) 1. A measurement method for measuring a mark formed on a substrate in a processing apparatus that processes a substrate held by a substrate stage in accordance with a recipe, the method comprising: a first step of acquiring information specifying an arbitrary tolerance value for a processing time of the substrate held by the substrate stage; a second step of determining, from among the plurality of marks formed on the substrate, additional marks to be measured in addition to the marks designated as measurement targets by the recipe, based on the tolerances designated by the information acquired in the first step; a third step of measuring the positions of the marks designated as measurement targets by the recipe and the positions of the additional marks determined in the second step; A measuring method comprising:

[0086] (Item 2) 2. The measurement method according to item 1, wherein the tolerance includes at least one of a value relating to the time allowed for processing one substrate and a value relating to the time allowed for a processing unit consisting of multiple substrates.

[0087] (Item 3) The second step comprises: an estimation step of estimating a processing time when performing processing specified by the recipe, based on an actual value of the processing time of the substrate held by the substrate stage and a predicted value of the processing time of a subsequent substrate; a calculation step of calculating a slack time that can be spent for measuring the mark formed on the substrate based on the tolerance specified by the information acquired in the first step and the processing time estimated in the estimation step; a determination step of determining the additional mark based on the margin time calculated in the calculation step; 3. The measurement method according to item 1 or 2, comprising:

[0088] (Item 4) 4. The measurement method according to item 3, wherein in the determination step, the number of marks that can be measured within all or part of the leeway time calculated in the calculation step is determined as the additional marks.

[0089] (Item 5) The second step comprises: a first estimation step of estimating a processing time when performing processing specified by the recipe, based on an actual value of a processing time of a substrate held by the substrate stage and a predicted value of a processing time of a subsequent substrate; a calculation step of calculating a slack time that can be spent for measuring the mark formed on the substrate based on the tolerance specified by the information acquired in the first step and the processing time estimated in the first estimation step; a second estimation step of estimating a transport time from when the substrate held by the substrate stage is carried out to when a subsequent substrate is carried in; a determination step of determining the additional mark based on either the leeway time calculated in the calculation step or the transport time estimated in the second estimation step; 3. The measurement method according to item 1 or 2, comprising:

[0090] (Item 6) 6. The measurement method according to item 5, wherein in the determination step, the margin time calculated in the calculation step and the transport time estimated in the second estimation step are compared, and the additional mark is determined based on the longer time.

[0091] (Item 7) 2. The measurement method according to item 1, wherein the tolerance includes a value relating to a time corresponding to an interval between substrate transfers to the substrate stage.

[0092] (Item 8) 8. The measurement method according to any one of items 1 to 7, wherein the substrate stage includes at least two stages for measuring the mark formed on the substrate and processing the substrate in parallel.

[0093] (Item 9) 9. The measurement method according to any one of items 1 to 8, wherein in the second step, the additional marks are determined in descending order of priority set for each of the plurality of marks.

[0094] (Item 10) 10. The measurement method according to item 9, wherein the priority is set to be higher as the degree of variation in the measurement results of the position of the mark increases.

[0095] (Item 11) 1. A method for aligning a substrate by measuring a mark formed on the substrate in a processing apparatus that processes a substrate held by a substrate stage according to a recipe, comprising: a first step of acquiring information specifying an arbitrary tolerance value for a processing time of the substrate held by the substrate stage; a second step of determining, from among the plurality of marks formed on the substrate, additional marks to be measured in addition to the marks designated as measurement targets by the recipe, based on the tolerances designated by the information acquired in the first step; a third step of measuring the positions of the marks designated as measurement targets by the recipe and the positions of the additional marks determined in the second step; a fourth step of aligning the substrate based on the positions of the marks measured in the third step and the positions of the additional marks; 1. A method for aligning a position, comprising:

[0096] (Item 12) a fifth step of determining, after the fourth step, a new additional mark to be measured from among the plurality of marks formed on the substrate, in addition to the mark designated as the measurement target by the recipe and the additional mark; a sixth step of measuring the position of the new additional mark determined in the fifth step; a seventh step of learning a model that derives parameters representing the position of the substrate held by the substrate stage, using the positions of the mark and the additional mark measured in the third step and the position of the new additional mark measured in the sixth step; 12. The alignment method according to item 11, further comprising:

[0097] (Item 13) Item 13. The alignment method according to item 12, wherein the position of the new additional mark measured in the sixth step is not used for aligning the substrate.

[0098] (Item 14) A step of aligning a substrate using the alignment method according to any one of items 11 to 13; processing the aligned substrate; A processing method comprising:

[0099] (Item 15) A processing apparatus that processes a substrate according to a recipe, a substrate stage for holding the substrate; a processing unit that performs processing to measure a mark formed on the substrate and align the substrate; and The process comprises: a first step of acquiring information specifying an arbitrary tolerance value for a processing time of the substrate held by the substrate stage; a second step of determining, from among the plurality of marks formed on the substrate, additional marks to be measured in addition to the marks designated as measurement targets by the recipe, based on the tolerances designated by the information acquired in the first step; a third step of measuring the positions of the marks designated as measurement targets by the recipe and the positions of the additional marks determined in the second step; a fourth step of aligning the substrate based on the positions of the marks measured in the third step and the positions of the additional marks; A processing device comprising:

[0100] (Item 16) Forming a pattern on a substrate using the processing method according to item 14; processing the substrate on which the pattern has been formed in the process; manufacturing an article from the processed substrate; A method for manufacturing an article, comprising:

[0101] (Item 17) A method for determining a mark to be measured from a plurality of marks formed on a substrate when processing the substrate held by a substrate stage according to a recipe, the method comprising: a first step of acquiring information specifying an arbitrary tolerance value for a processing time of the substrate held by the substrate stage; a second step of determining, from among the plurality of marks formed on the substrate, additional marks to be measured in addition to the marks designated as measurement targets by the recipe, based on the tolerances designated by the information acquired in the first step; A method for determining whether a parameter is a parameter that is a function of a parameter.

[0102] (Item 18) Item 18. A program for causing a computer to execute the determination method according to Item 17.

[0103] The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0104] 10: Substrate processing apparatus 200: Substrate stage 210: Substrate 211: Mark 100: Main control unit 300: Control instruction unit

Claims

1. 1. A measurement method for measuring a mark formed on a substrate in a processing apparatus that processes a substrate held by a substrate stage in accordance with a recipe, the method comprising: a first step of acquiring information specifying an arbitrary tolerance value for a processing time of the substrate held by the substrate stage; a second step of determining, from among the plurality of marks formed on the substrate, additional marks to be measured in addition to the marks designated as measurement targets by the recipe, based on the tolerances designated by the information acquired in the first step; a third step of measuring the positions of the marks designated as measurement targets by the recipe and the positions of the additional marks determined in the second step; A measuring method comprising:

2. 2. The measurement method according to claim 1, wherein the tolerance value includes at least one of a value relating to the time allowed for processing one substrate and a value relating to the time allowed for a processing unit consisting of multiple substrates.

3. The second step comprises: an estimation step of estimating a processing time when performing processing specified by the recipe, based on an actual value of the processing time of the substrate held by the substrate stage and a predicted value of the processing time of a subsequent substrate; a calculation step of calculating a slack time that can be spent for measuring the mark formed on the substrate based on the tolerance value specified by the information acquired in the first step and the processing time estimated in the estimation step; a determination step of determining the additional mark based on the margin time calculated in the calculation step; 2. The measurement method according to claim 1, further comprising:

4. 4. The measurement method according to claim 3, wherein the determining step determines, as the additional marks, marks whose number can be measured within all or part of the leeway time calculated in the calculating step.

5. The second step comprises: a first estimation step of estimating a processing time when performing processing specified by the recipe, based on an actual value of a processing time of a substrate held by the substrate stage and a predicted value of a processing time of a subsequent substrate; a calculation step of calculating a surplus time that can be spent for measuring the mark formed on the substrate based on the tolerance value specified by the information acquired in the first step and the processing time estimated in the first estimation step; a second estimation step of estimating a transport time from when the substrate held by the substrate stage is unloaded to when a subsequent substrate is loaded; a determination step of determining the additional mark based on either the leeway time calculated in the calculation step or the transport time estimated in the second estimation step; 2. The measurement method according to claim 1, further comprising:

6. 6. The measurement method according to claim 5, wherein the determination step compares the margin time calculated in the calculation step with the transport time estimated in the second estimation step, and determines the additional mark based on the longer time.

7. 2. The measurement method according to claim 1, wherein the tolerance value includes a value relating to a time corresponding to an interval between substrate transfers to the substrate stage.

8. 2. The measurement method according to claim 1, wherein the substrate stage includes at least two stages for performing measurement of the mark formed on the substrate and processing of the substrate in parallel.

9. 2. The measurement method according to claim 1, wherein in the second step, the additional marks are determined in descending order of priority set for each of the plurality of marks.

10. 10. The measurement method according to claim 9, wherein the priority is set to be higher as the degree of variation in the measurement results of the position of the mark increases.

11. 1. A method for aligning a substrate by measuring a mark formed on the substrate in a processing apparatus that processes a substrate held by a substrate stage according to a recipe, comprising: a first step of acquiring information specifying an arbitrary tolerance value for a processing time of the substrate held by the substrate stage; a second step of determining, from among the plurality of marks formed on the substrate, additional marks to be measured in addition to the marks designated as measurement targets by the recipe, based on the tolerances designated by the information acquired in the first step; a third step of measuring the positions of the marks designated as measurement targets by the recipe and the positions of the additional marks determined in the second step; a fourth step of aligning the substrate based on the positions of the marks measured in the third step and the positions of the additional marks; 1. A method for aligning a position, comprising:

12. a fifth step of determining, after the fourth step, a new additional mark to be measured from among the plurality of marks formed on the substrate, in addition to the mark designated as the measurement target by the recipe and the additional mark; a sixth step of measuring the position of the new additional mark determined in the fifth step; a seventh step of learning a model that derives parameters representing the position of the substrate held by the substrate stage, using the positions of the mark and the additional mark measured in the third step and the position of the new additional mark measured in the sixth step; The method of claim 11 further comprising:

13. 13. The alignment method according to claim 12, wherein the position of the new additional mark measured in the sixth step is not used for aligning the substrate.

14. aligning a substrate using the alignment method of claim 11; processing the aligned substrate; A processing method comprising:

15. A processing apparatus that processes a substrate according to a recipe, a substrate stage for holding the substrate; a processing unit that performs processing to measure a mark formed on the substrate and align the substrate; and The process comprises: a first step of acquiring information specifying an arbitrary tolerance value for a processing time of the substrate held by the substrate stage; a second step of determining, from among the plurality of marks formed on the substrate, additional marks to be measured in addition to the marks designated as measurement targets by the recipe, based on the tolerances designated by the information acquired in the first step; a third step of measuring the positions of the marks designated as measurement targets by the recipe and the positions of the additional marks determined in the second step; a fourth step of aligning the substrate based on the positions of the marks measured in the third step and the positions of the additional marks; A processing device comprising:

16. forming a pattern on a substrate using the process of claim 14; processing the substrate on which the pattern has been formed in the process; manufacturing an article from the processed substrate; A method for manufacturing an article, comprising:

17. 1. A method for determining a mark to be measured from a plurality of marks formed on a substrate when processing the substrate held by a substrate stage according to a recipe, the method comprising: a first step of acquiring information specifying an arbitrary tolerance value for a processing time of the substrate held by the substrate stage; a second step of determining, from among the plurality of marks formed on the substrate, additional marks to be measured in addition to the marks designated as measurement targets by the recipe, based on the tolerances designated by the information acquired in the first step; A method for determining whether a parameter is a parameter that is a function of a parameter.

18. A program causing a computer to execute the determination method according to claim 17.

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