Exposure apparatus, anomaly detection method, and method for manufacturing articles.

Abstract

This technology offers advantages in improving the accuracy of anomaly detection. [Solution] An exposure apparatus for exposing multiple shot areas on a substrate via a master plate, comprising: a master plate stage for holding the master plate; a substrate stage for holding the substrate; a measurement unit for measuring the operating state of at least one of the master plate stage and the substrate stage; and an abnormality detection unit for detecting an abnormality in the exposure apparatus based on the measurement data from the measurement unit. The abnormality detection unit detects an abnormality using measurement data from an exposure preparation period during a non-exposure period in which no shot areas are exposed, in which the acceleration of the master plate stage or the substrate stage is similar to that of the exposure period in which the shot areas are exposed.

Description

Technical Field

[0001] The present invention relates to an exposure apparatus, an abnormality detection method, and a method for manufacturing an article.

Background Art

[0002] As a lithography apparatus used in a manufacturing process of a semiconductor device or the like, an exposure apparatus that performs so-called scanning exposure for transferring a pattern of a reticle onto a substrate by scanning the substrate with slit light that has passed through the reticle is known.

[0003] In the abnormality detection method of Patent Document 1, during synchronous movement during exposure, a synchronous error signal corresponding to a synchronous error between the reticle and the substrate is detected at a predetermined sampling interval. Then, the synchronous error signal is converted into a moving standard deviation, and frequency analysis and time series analysis are performed to detect an abnormality of the reticle or the substrate.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, when detecting an abnormal state of an exposure apparatus from device data as in Patent Document 1, there are cases where an abnormality cannot be detected only by data during exposure.

[0006] Therefore, an exemplary object of the present invention is to provide a technique advantageous in improving the detection accuracy of an abnormality.

Means for Solving the Problems

[0007] To achieve the above objective, an exposure apparatus as one aspect of the present invention is an exposure apparatus for exposing a plurality of shot regions on a substrate via a master plate, comprising: a master plate stage for holding the master plate; a substrate stage for holding the substrate; a measurement unit for measuring the operating state of at least one of the master plate stage and the substrate stage; and an abnormality detection unit for detecting an abnormality in the exposure apparatus based on the measurement data from the measurement unit, wherein the abnormality detection unit detects the abnormality using the measurement data from an exposure preparation period during a non-exposure period in which the acceleration of the master plate stage or the substrate stage is similar to that of an exposure period in which the shot regions are exposed. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a technology that is advantageous in that it improves the accuracy of anomaly detection. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram showing the configuration of an exposure apparatus as one aspect of the present invention. [Figure 2] This diagram illustrates the movement trajectories of the substrate stage and the master plate stage. [Figure 3] This figure shows an example of a drive profile for the substrate stage relative to the movement trajectory shown in Figure 2. [Figure 4] This figure shows an example of the drive profile of the master plate stage relative to the movement trajectory shown in Figure 2. [Figure 5] This is a schematic diagram showing an example of measurement data acquired by the first and second measurement units. [Figure 6] This is a schematic diagram showing an example of reference data in the shot region N. [Figure 7] This is a schematic diagram representing cluster centers using the K-means method. [Figure 8] This is a schematic diagram showing an example of test data and reference data. [Figure 9] This is a block diagram showing the functional configuration of the anomaly detection unit. [Figure 10]This is a schematic diagram showing an example of standard data and inspection data for a set period. [Figure 11] This is a schematic diagram showing an example of reference data and inspection data for exposure period. [Figure 12] This is a flowchart showing the anomaly detection process according to the first embodiment. [Figure 13] This is a schematic diagram showing an example of an abnormality detection result in the first embodiment. [Modes for carrying out the invention]

[0010] The embodiments will be described in detail below with reference to the attached drawings. Note that the following embodiments do not limit the invention as defined in the claims. While the embodiments describe multiple features, not all of these features are essential to the invention, and the features may be combined in any way. Furthermore, in the attached drawings, identical or similar configurations are given the same reference numerals, and redundant descriptions are omitted.

[0011] Figure 1 is a schematic diagram showing the configuration of an exposure apparatus 100 as one aspect of the present invention. The exposure apparatus 100 is a lithography apparatus used in the lithography process, which is a manufacturing process for devices such as semiconductor elements, and is used to form a pattern on a substrate using a master plate (reticle or mask). The exposure apparatus 100 is a scanning exposure apparatus (scanner) that employs a step-and-scan method to transfer the pattern of the master plate to the substrate by exposing the substrate while scanning the master plate and the substrate relatively (scanning exposure).

[0012] In this specification and the accompanying drawings, directions are indicated in an XYZ coordinate system, where the direction along the optical axis of the projection optical system 14 (described later) is defined as the Z-axis, and the two directions parallel to the plane perpendicular to the Z-axis and perpendicular to each other are defined as the X-axis and Y-axis. Furthermore, the directions parallel to the X-axis, Y-axis, and Z-axis in the XYZ coordinate system are defined as the X-direction, Y-direction, and Z-direction, respectively. Hereinafter, the Z-direction may be referred to as the height direction. In this embodiment, the direction in which the original plate and the substrate are scanned relative to each other (scanning direction) is defined as the Y-direction (+Y direction or -Y direction).

[0013] As shown in FIG. 1, the exposure apparatus 100 includes an illumination optical system 11, a reticle stage 13 that holds a reticle 12, a projection optical system 14, and a substrate stage 16 that holds a substrate 15. The exposure apparatus 100 also includes a surface position measurement unit 17, a first measurement unit 18, a second measurement unit 19, a control unit 20, a reticle detection unit 21, a substrate detection unit 22, and an abnormality detection unit 23.

[0014] The control unit 20 is constituted by a computer (information processing apparatus) including a processor such as a CPU and a memory, and comprehensively controls each part of the exposure apparatus 100 according to a program stored in a storage unit. In this embodiment, the control unit 20 controls the process of transferring the pattern of the reticle 12 onto the substrate 15 while relatively scanning the reticle 12 and the substrate 15, that is, controls the scanning exposure of the substrate 15. Further, the control unit 20 controls the abnormality detection unit 23 to detect an abnormality in the exposure apparatus 100.

[0015] The illumination optical system 11 includes a light shielding member such as a masking blade, and shapes light emitted from a light source (not shown) such as an excimer laser into带状 or arc-shaped light (slit light) having a longitudinal direction in the X direction, for example, and illuminates a part of the reticle 12 with such light.

[0016] The reticle 12 and the substrate 15 are respectively held by the reticle stage 13 and the substrate stage 16, and are arranged at optically conjugate positions (the object plane and the image plane of the projection optical system 14) via the projection optical system 14.

[0017] The projection optical system 14 has a predetermined projection magnification (for example, 1 / 2 times or 1 / 4 times), and projects the pattern formed on the reticle 12 onto the substrate 15. The area of the substrate 15 where the pattern of the reticle 12 is projected (that is, the area irradiated with the slit light) is hereinafter referred to as an exposure slit.

[0018] The master plate stage 13 and the substrate stage 16 are configured to be driveable in a direction perpendicular to the optical axis of the projection optical system 14 (the optical axis of the slit light) (for example, the Y direction). The master plate stage 13 and the substrate stage 16 are driven (scanned) relatively at a speed ratio corresponding to the projection magnification of the projection optical system 14, while synchronizing with each other. This allows the exposure slit to be scanned on the substrate, transferring the pattern of the master plate 12 to the substrate 15 (the shot area). By sequentially repeating this scanning exposure for each of the multiple shot areas on the substrate, the exposure process for one substrate 15 is completed. Here, a shot area refers to the area on the substrate 15 that is exposed in one scanning exposure in the exposure apparatus 100. Multiple shot areas are divided on the substrate.

[0019] The first measurement unit 18 includes, for example, a laser interferometer and measures the position of the master plate stage 13. The laser interferometer included in the first measurement unit 18 measures the displacement of the master plate stage 13 from a reference position by, for example, irradiating a reflector 13a provided on the master plate stage 13 with laser light and detecting the laser light reflected by the reflector 13a. Based on the displacement of the master plate stage 13 from the reference position, the first measurement unit 18 can obtain the current position of the master plate stage 13.

[0020] The second measurement unit 19 includes, for example, a laser interferometer and measures the position of the substrate stage 16. The laser interferometer included in the second measurement unit 19 measures the displacement of the substrate stage 16 from a reference position by, for example, irradiating a reflector 16a provided on the substrate stage 16 with laser light and detecting the laser light reflected by the reflector 16a. Based on the displacement of the substrate stage 16 from the reference position, the second measurement unit 19 can obtain the current position of the substrate stage 16.

[0021] Based on the current position of the master plate stage 13 acquired by the first measurement unit 18 and the current position of the substrate stage 16 acquired by the second measurement unit 19, the control unit 20 controls the driving of the master plate stage 13 and the substrate stage 16 in the XY direction. In this embodiment, the first measurement unit 18 and the second measurement unit 19 each use a laser interferometer to measure the position of the master plate stage 13 and the substrate stage 16, but are not limited to this, and for example, encoders may be used.

[0022] The surface position measurement unit 17 includes, for example, a light-emitting unit that projects light onto the surface of the substrate 15 and a light-receiving unit that receives light reflected from the surface of the substrate 15, and measures the height (position in the Z direction) of the surface of the substrate 15.

[0023] The original plate detection unit 21 detects alignment marks provided on the original plate 12 and alignment marks provided on the original plate stage 13. The control unit 20 calculates the positional displacement (amount of positional displacement) of the original plate 12 relative to the original plate stage 13 by calculating the relative positions of the alignment marks detected by the original plate detection unit 21. By providing multiple alignment marks in the X direction for both the original plate 12 and the original plate stage 13, it becomes possible to determine the positional displacement of the original plate 12 in the XYθ direction relative to the original plate stage 13.

[0024] The substrate detection unit 22 detects multiple alignment marks provided in the sample shot area among multiple shot areas on the substrate. The control unit 20 calculates the arrangement information (shot layout) of the multiple shot areas on the substrate by processing the detection results of the substrate detection unit 22.

[0025] In this embodiment, the original plate detection unit 21 and the substrate detection unit 22 are configured as off-axis systems that detect each mark without going through the projection optical system 14, but are not limited to this. For example, the original plate detection unit 21 and the substrate detection unit 22 may be configured as TTL (Through The Lens) systems that detect each mark via the projection optical system 14.

[0026] The anomaly detection unit 23 is composed of a computer (information processing device) including, for example, a CPU or other processor and memory, and performs anomaly detection processing according to a program stored in the memory unit, as described later. The detailed configuration of the anomaly detection unit 23 will be described later.

[0027] Here, with reference to Figures 2 to 4, the drive profiles of the substrate stage 16 and the master plate stage 13 for realizing scanning exposure of the substrate 15 while driving the substrate 15 and the master plate 12 with acceleration or deceleration will be described. The drive profile is used in the control unit 20 to control the driving of the substrate stage 16 and the master plate stage 13. That is, the drive profile defines the driving of the master plate stage 13 and the substrate stage 16. Figure 2 is a diagram illustrating the movement trajectories of the substrate stage 16 and the master plate stage 13. Figure 2(A) is a diagram showing the movement trajectory of the substrate stage 16 when the substrate stage 16 is driven based on a conventional drive profile. Figure 2(B) is a diagram showing the movement trajectory of the master plate stage 13 (exposure slit) when the master plate stage 13 is driven based on a conventional drive profile. Figure 3 is a diagram showing an example of the drive profile of the substrate stage 16 for the movement trajectory shown in Figure 2. In Figure 3, graph GP1 (upper graph) is the acceleration profile of the substrate stage 16, showing the time-series change in the acceleration of the substrate stage 16 in the Y direction. Furthermore, in Figure 3, graph GP2 (lower graph) is the speed profile of the substrate stage 16, showing the time-series change in the speed of the substrate stage 16 in the Y direction. Figure 4 is a diagram showing an example of the drive profile of the master plate stage 13 with respect to the movement trajectory shown in Figure 2. In Figure 3, graph GP3 (upper graph) is the acceleration profile of the master plate stage 13, showing the time-series change in the acceleration of the master plate stage 13 in the Y direction. Furthermore, in Figure 3, graph GP4 (lower graph) is the speed profile of the master plate stage 13, showing the time-series change in the speed of the master plate stage 13 in the Y direction.

[0028] The substrate stage 16 operates by scanning in the -Y direction over the shot area N to be exposed, then stepping in the X direction, and scanning in the +Y direction over the next shot area N+1 to be exposed. On the other hand, the master plate stage 13 operates by scanning in the +Y direction over the shot area N to be exposed, then not stepping in the X direction, and scanning in the -Y direction over the next shot N+1 to be exposed. In other words, when the substrate stage 16 moves in the positive direction (+Y direction), the master plate stage 13 moves in the negative direction (-Y direction). At this time, the acceleration of the substrate stage 16 and the acceleration of the master plate stage 13 are controlled to move at the same value, except for the reversal of the sign. Similarly, the speed of the substrate stage 16 and the speed of the master plate stage 13 are controlled to be the same value, except for the reversal of the sign. By controlling the acceleration and speed of the master plate stage 13 and the substrate stage 16 to be the same, except for the reversal of the sign, highly productive exposure is achieved.

[0029] When scanning the shot area N to be exposed, the speeds of the substrate stage 16 and the master plate stage are accelerated or decelerated to the desired speed during the non-exposure period 201. The non-exposure period 201 includes a constant acceleration period and a period in which the acceleration is varied to the desired acceleration using a function of order or higher, and is composed of a combination of two corresponding drive profiles. During the non-exposure period 201, accelerating the substrate stage 16 at an acceleration higher than the starting acceleration of the exposure period 202 has the effect of shortening the time it takes for the substrate stage 16 to accelerate to the desired speed.

[0030] During exposure period 202, the shot area N is scanned and exposed while the substrate stage 16 and master plate stage 13 are driven at a constant speed based on the acceleration profiles shown in GP1 and GP3 (hereinafter sometimes referred to as constant-speed exposure). Subsequently, exposure period 202 is connected to non-exposure period 203. The drive time T is calculated as (shot field of view Yd of shot area N + slit size Ysilt of exposure slit) / average speed Vave of the substrate stage 16 or master plate stage 13 during exposure period 202.

[0031] Furthermore, in the drive profile of this embodiment, a settling period 207 is provided as an exposure preparation period for the substrate stage 16 and the master plate stage 13, immediately before the exposure period 202) during the non-exposure period 201 in which the shot area is not exposed. Here, the settling period 207 is a waiting period until the deviations of the master plate stage 13 and the substrate stage 16 converge, and it is a waiting period until the deviations converge from the state in which the master plate stage 13 and the substrate stage 16 have moved a large distance between the shot areas and have large deviations. For this reason, the data obtained from the first measurement unit 18 and the second measurement unit 19 will show a state in which the deviations are large in the first half of the settling period 207, and as time passes the deviations converge, they will gradually approach the state in which the deviations are in which the exposure period 202 is. In other words, the settling period 207 is a period in which the characteristics of the exposure apparatus are easily revealed, and in an exposure apparatus with good characteristics, the deviations will converge quickly in the first half of the settling period 207. On the other hand, in an exposure apparatus with poor characteristics, it will take a long time for the deviations to converge and they will not converge until the second half of the settling period 207. When an exposure device with such poor characteristics is considered a faulty device, it is difficult to detect the abnormality based solely on the exposure period 202. Therefore, in this embodiment, abnormality detection of the exposure device is performed using measurement data from the settling period 207.

[0032] Alternatively, a settling time for the substrate stage 16 may be provided during the exposure period 202, and the shot area N may be scanned and exposed during a portion of the exposure period 202. Furthermore, by changing the starting acceleration of the exposure period 202, the rate of change of the speed of the substrate stage 16 during scanning exposure can be arbitrarily set.

[0033] The total exposure amount of light (exposure light) irradiated onto the substrate 15 from the light source (not shown) must always be kept constant. Therefore, the shot area N is scanned and exposed while changing the exposure amount in accordance with the change in speed of the substrate stage 16. For example, the exposure amount is controlled so that it is increased when the speed of the substrate stage 16 is fast, and decreased when the speed of the substrate stage 16 is slow.

[0034] During the non-exposure period 203, the substrate stage 16 is driven in steps in the X direction to scan and expose the next target shot area N+1, while the drive profile is decelerated based on the same but sign-inverted drive profile as in the non-exposure period 201. During the non-exposure period 204, exposure period 205, and non-exposure period 206, the substrate stage 16 is driven based on the same but sign-inverted drive profile as in the non-exposure period 201, exposure period 202, and non-exposure period 203, respectively. This allows for continuous scanning exposure of the shot area N and the shot area N+1, as shown in Figure 2.

[0035] <First Embodiment> The following describes the process for detecting an abnormality in the exposure apparatus 100 according to the first embodiment. Specifically, in the abnormality detection process according to the first embodiment, an abnormality in the exposure apparatus 100 is detected based on measurement data related to the master plate stage 13 acquired by the first measurement unit 18 and measurement data related to the substrate stage 16 acquired by the second measurement unit 19.

[0036] Figure 5 is a schematic diagram showing an example of measurement data acquired by the first measurement unit 18 and the second measurement unit 19. Specifically, Figure 5 schematically shows the output data of measurement sensors A to D for measuring the operating state of the exposure apparatus 100 in the shot region N208 shown in Figures 3 and 4. The processing in shot region N will be described below, but the same processing is performed in other shot regions, so the processing in other shot regions will be omitted.

[0037] Measurement sensors A and B are sensors that measure the operating state of the master plate stage 13 included in the first measurement unit 18. The measurement data acquired using measurement sensors A and B is measured and calculated in the first measurement unit 18. The measurement data 400TA(N) from measurement sensor A indicates the displacement of the master plate stage 13 relative to the reference position, and the data 400TB(N) from measurement sensor B indicates its deviation. Measurement sensors C and D are sensors that measure the operating state of the substrate stage 16 included in the second measurement unit 19. The measurement data acquired using measurement sensors C and D is measured and calculated in the second measurement unit 19. The data 400TC(N) from measurement sensor C indicates the displacement of the substrate stage 16 relative to the reference position, and the data 400TD(N) from measurement sensor D indicates its deviation.

[0038] The exposure apparatus 100 is equipped with hundreds of other sensors not shown, in addition to measurement sensors A to D. However, in this embodiment, only the four sensors A to D are explicitly shown for the sake of simplicity, and the same processing may be performed on the other sensors not shown. For example, abnormality detection processing may be performed using the measurement data from the surface position measurement unit 17.

[0039] Next, we will explain the reference data obtained from measurement sensors A to D of a normal exposure apparatus. Figure 6 is a schematic diagram showing an example of reference data in shot region N208. The reference data in shot region N208 is measurement data calculated based on the measurement results of measurement sensors A to D of normal apparatus 1 to normal apparatus 3 in shot region N208. Normal apparatus 1 to normal apparatus 3 are apparatuses that have been confirmed to be free of abnormalities, and the reference data is data calculated based on the measurement results of measurement sensors A to D obtained during the normal operation of normal apparatus 1 to normal apparatus 3. The reference data can also be said to represent an ideal waveform.

[0040] Normally, exposure equipment requires extremely high exposure accuracy, and therefore the control accuracy of each operating part, such as the stage, is also very high. During normal operation, the data from each measurement sensor A to D will be similar at each time point for normal equipment 1 to normal equipment 3. Specifically, for measurement sensor A, the waveform shapes of the measurement data 500N1A(N) from normal equipment 1, 500N2A(N) from normal equipment 2, and 500N3A(N) from normal equipment 3 have very similar characteristics. Similarly, for measurement sensors B to C, the waveforms from normal equipment 1, 2, and 3 each have similar waveform shapes. Furthermore, during the exposure period 202, the exposure equipment 100 is in the process of exposure, resulting in the highest control accuracy. Therefore, the waveform shapes of the measurement data acquired from each device during the exposure period 202 have particularly similar characteristics. In this embodiment, an abnormality in the exposure equipment 100 is detected based on the similarity of the waveforms from measurement sensors A to D.

[0041] The reference data 500NA(N) for measurement sensor A shown in Figure 6 is the reference data for normal operation calculated based on data acquired from measurement sensor A of normal devices 1 to 3. The reference data 500NB(N), 500NC(N), and 500ND(N) are the reference data for normal operation calculated based on data acquired from measurement sensors B to D of normal devices 1 to 3. In this embodiment, the reference data for each measurement sensor during normal operation (500NA(N), 500NB(N), 500NC(N), 500ND(N)) is calculated using the K-means method, a machine learning clustering technique. Specifically, the reference data 500NA(N) is calculated by calculating cluster-centered data from the measurement data acquired by measurement sensor A of normal devices 1 to 3 and using that as the reference data. Here, the K-means method is applied with a cluster count of 1.

[0042] Figure 7 is a schematic diagram representing the cluster center using the K-means method. This figure shows the cluster center using the K-means method when the number of clusters is 1. As shown in Figure 7, since there is only one cluster, all sample data are classified into one cluster, and the center of the cluster becomes the center of the sample data. In this embodiment, the cluster center calculated by the K-means method is kept as reference data. In this embodiment, the K-means method is used, but reference data may be generated using other clustering methods, machine learning, or statistical methods.

[0043] Figure 8 is a schematic diagram showing an example of inspection data and reference data. Figure 8 schematically shows an example of reference data (500NA(N), 500NB(N), 500NC(N), 500ND(N)) from measurement sensors A to D and inspection data (400TA(N), 400TB(N), 400TC(N), 400TD(N)) which is measurement data acquired from the exposure apparatus 100 to be inspected. In this embodiment, abnormalities are detected based on the similarity of the waveforms of the reference data (500NA(N), 500NB(N), 500NC(N), 500ND(N)) during normal operation shown in Figure 8 and the inspection data (400TA(N), 400TB(N), 400TC(N), 400TD(N)) acquired from the exposure apparatus 100 to be inspected.

[0044] Here, the non-exposure period, excluding the settling period 207 and the exposure period 202, is the period during which the master plate stage 13 and the substrate stage 16 move between shot areas. Therefore, even in a normal exposure apparatus, the operation of each stage affects the output of each sensor, causing significant fluctuations. In other words, this is a period during which waveform fluctuations caused by abnormalities in the exposure apparatus become difficult to detect due to the influence of the master plate stage 13 and the substrate stage 16. For this reason, in this embodiment, abnormalities are detected using measurement data from the exposure period 202, which has very high operational accuracy, and measurement data from the settling period 207, where the acceleration of the master plate stage 13 and the substrate stage 16 is similar to (or nearly identical to), preferably approximately the same as, and even more preferably the same as, that of the exposure period 202. Note that in the constant velocity exposure drive profile shown in Figures 3 and 4, the acceleration during the settling period 207 and the exposure period 202 is 0. That is, in the case of constant velocity exposure, abnormalities are detected using measurement data from the settling period 207, where the acceleration of the master plate stage 13 and the substrate stage 16 is close to 0, preferably 0.

[0045] Next, we will describe the abnormality detection unit 23, which detects abnormalities using measurement data from the exposure period 202 and the settling period 207. Figure 9 is a block diagram showing the functional configuration of the abnormality detection unit 23. The abnormality detection unit 23 comprises an abnormality determination unit 801, a similarity calculation unit 802, a first holding unit 803, a second holding unit 804, a first acquisition unit 805, and a second acquisition unit 806.

[0046] The first holding unit 803 holds (stores) reference data for N shots during the settling period 207. For example, the reference data D1NA(N) held in the first holding unit 803 is data calculated based on the measurement results of measurement sensor A of normal devices 1 to 3 during the settling period 207 in the shot area N (the Nth shot area) of the exposure target. Figure 10 is a schematic diagram showing an example of reference data and inspection data for the settling period 207. The first holding unit 803 similarly holds reference data D1NB(N) to reference data D1ND(N) calculated based on the measurement results of measurement sensors B to D.

[0047] The second holding unit 804 holds (stores) reference data for N shots during the exposure period 202. For example, the reference data D2NA(N) held in the second holding unit 804 is data calculated based on the measurement results of measurement sensor A of normal devices 1 to 3 during the exposure period 202 in the shot area N (the Nth shot area) of the exposure target shown in Figure 11. Figure 11 is a schematic diagram showing an example of reference data and inspection data for the exposure period 202. The second holding unit 804 similarly holds reference data D2NB(N) to reference data D2ND(N) calculated based on the measurement data acquired by measurement sensors B to D.

[0048] The first acquisition unit 805 acquires measurement data from measurement sensors A to D based on instructions from the control unit 20, and stores the measurement data for N shots during the settling period 207 as inspection data. Specifically, for example, during the settling period 207 in the shot area N that is the exposure target, the first acquisition unit 805 acquires the measurement data measured by measurement sensor A of the exposure apparatus 100 that is the subject of inspection at a predetermined timing and stores it as inspection data. An example of inspection data D1TA(N) acquired by the first acquisition unit 805 is shown in Figure 10. Similarly, the first acquisition unit 805 also acquires and stores inspection data D1TB(N) to inspection data D1TD(N) measured by measurement sensors B to D at predetermined timings. An example of inspection data D1TB(N) to inspection data D1TD(N) is also shown in Figure 10.

[0049] The second acquisition unit 806 acquires measurement data from measurement sensors A to D based on instructions from the control unit 20, and stores the measurement data for N shots during the exposure period 202 as inspection data. Specifically, for example, the second acquisition unit 806 acquires the measurement data measured by measurement sensor A of the exposure apparatus 100 to be inspected during the exposure period 202 in the shot area N that is the target of exposure, at a predetermined timing, and stores it as inspection data. An example of the acquired inspection data D2TA(N) is shown in Figure 11. Similarly, the second acquisition unit 806 acquires the inspection data D2TB(N) to inspection data D2TD(N) measured by measurement sensors B to D at a predetermined timing, and stores each of them. An example of the inspection data D2TB(N) to inspection data D2TD(N) is also shown in Figure 11.

[0050] The similarity calculation unit 802 calculates the similarity between the waveforms of the reference data and the inspection data. Specifically, the similarity calculation unit 802 acquires the reference data and the inspection data according to the instructions of the control unit 20 and calculates the waveform similarity from the two data. In this embodiment, the similarity calculation unit 802 quantifies the similarity between the two waveforms using Dynamic Time Warping (hereinafter referred to as DTW). DTW calculates the distance between each point of the two time series data by brute force to find the path (warping path) that minimizes the distance between the two time series data, and defines its length as the Dynamic Time Warping Distance (hereinafter referred to as DTW distance). The smaller the DTW distance value, the higher the similarity, and by setting a predetermined judgment value, it becomes possible to determine normal or abnormal from the perspective of similarity.

[0051] The abnormality detection unit 801 determines an abnormality based on the value calculated by the similarity calculation unit 802. The abnormality detection unit 801 determines an abnormality based on a threshold value for the DTW distance calculated by the similarity calculation unit 802. In other words, in this embodiment, an abnormality is detected when the similarity to the waveform shape, which is the reference data for normal operation, is lower than the threshold value.

[0052] In this embodiment, the abnormality detection unit 23 is configured separately from the control unit 20, but the abnormality detection unit 23 may be part of the control unit 20. In other words, the control unit 20 may have the functions of the abnormality detection unit 23.

[0053] Next, the abnormality detection process of the abnormality detection unit 23 will be described. Figure 12 is a flowchart of the abnormality detection process according to the first embodiment. The abnormality detection process is realized, for example, by the CPU of the abnormality detection unit 23 reading and executing a program stored in memory. Hereafter, the abnormality detection unit 23 or each part of the abnormality detection unit 23 will be described as the main body of each process, but in reality, the corresponding function is realized by the CPU executing the corresponding program. Figure 13 is a schematic diagram showing an example of the abnormality determination result in the first embodiment. Figure 13(A) shows the abnormality determination result in the setting period 207, and Figure 13(B) shows the abnormality determination result in the exposure period 202. In Figure 13, the numbers in the upper row indicate the DTW distance, and the numbers in the lower row indicate the abnormality determination result for each shot area number (hereinafter referred to as the shot number).

[0054] In step S1100, the anomaly detection unit 23 starts an anomaly detection operation based on instructions from the control unit 20. In step S1101, the similarity calculation unit 802 acquires N shots of reference data D1NA(N), D1NB(N), D1NC(N), and D1ND(N) for a settling period 207 from the first holding unit 803. In this embodiment, in order to process the N shots of data in parallel, the similarity calculation unit 802 acquires N shots of reference data from the first holding unit 803.

[0055] In step S1102, the similarity calculation unit 802 acquires inspection data D1TA(N), D1TB(N), D1TC(N), and D1TD(N) for a settling period 207 from the first acquisition unit 805. In other words, step S1102 is an acquisition process in which measurement data, which measures the operating state of the original stage 13 and substrate stage 16 of the exposure apparatus 100 to be inspected, is acquired as inspection data. In step S1102, as in step S1101, the similarity calculation unit 802 acquires inspection data for N shots from the first acquisition unit 805 in order to process N shots of data in parallel.

[0056] In step S1103, the similarity calculation unit 802 calculates the DTW distance between the inspection data D1TA(N) and the reference data D1NA(N) of measurement sensor A in the shot region N, which is the exposure target shown in Figure 10. In this embodiment, the similarity calculation unit 802 calculates the DTW distance for N shots in parallel processing and calculates the DTW distance for all shots from shot number 1 to shot number N of measurement sensor A in step S1103. That is, the similarity calculation unit 802 calculates the similarity for each shot region. Similarly, the similarity calculation unit 802 calculates the DTW distance for all shots from shot number 1 to shot number N for D1TB(N) and D1NB(N) of measurement sensor B, D1TC(N) and D1NC(N) of measurement sensor C, and D1TD(N) and D1ND(N) of measurement sensor D in parallel processing.

[0057] In step S1103, the numerical value in the upper part of Figure 13(A) is calculated as the DTW distance. That is, the similarity calculation unit 802 calculates the DTW distance for each shot for each measurement sensor, i.e., for each measurement data. Note that the DTW distance values ​​shown in Figure 13 are simplified for illustrative purposes, and the calculated DTW distance may be transformed into a more manageable numerical value by normalization or other means.

[0058] In step S1104, the abnormality determination unit 801 determines an abnormality using a predetermined threshold value for the DTW distance calculated in step S1103. That is, step S1104 is an abnormality detection process that detects an abnormality in the exposure device 100 based on the inspection data. In this embodiment, the threshold value for the settling period is set to 5, and if the value of the DTW distance is greater than the threshold, the exposure device 100 is determined to be in an abnormal state, and if the value of the DTW distance is less than or equal to the threshold, the exposure device 100 is determined to be in a normal state. In step S1104, as shown in the lower part of Figure 13(A), the determination result for each shot is obtained for each measurement sensor. In Figure 13(A), the DTW distance is greater than the threshold value for measurement sensor C and measurement sensor D in shot number N. Therefore, the abnormality determination unit 801 determines that the exposure device 100 is abnormal (in an abnormal state).

[0059] In step S1105, if any of the judgment results obtained in step S1104 indicate an abnormality for any of the measurement sensors or shot numbers (Yes), the process proceeds to step S1112. The abnormality detection unit 23 then notifies the control unit 20 that the exposure apparatus 100 is in an abnormal state, and the control unit 20 performs a predetermined operation to terminate the process. On the other hand, in step S1105, if all the judgment results obtained in step S1104 indicate a normal state (No), the process proceeds to step S1106 of the abnormality detection flowchart during the exposure period.

[0060] In step S1106, the similarity calculation unit 802 acquires N shots worth of reference data D2NA(N), D2NB(N), D2NC(N), and D2ND(N) for the exposure period 202 from the second holding unit 804. In this embodiment, in order to process the N shots worth of data in parallel, the similarity calculation unit 802 acquires N shots worth of reference data from the second holding unit 804.

[0061] In step S1107, the similarity calculation unit 802 acquires inspection data D2TA(N), D2TB(N), D2TC(N), and D2TD(N) for the exposure period 202 from the second acquisition unit 806. Similar to step S1106, the similarity calculation unit 802 acquires inspection data for N shots from the second acquisition unit 806 in order to process the data for N shots in parallel.

[0062] In step S1108, the similarity calculation unit 802 calculates the DTW distance between the inspection data D2TA(N) and the reference data D2NA(N) of measurement sensor A in the shot region N, which is the exposure target shown in Figure 11. In this embodiment, the similarity calculation unit 802 calculates the DTW distance for N shots by parallel processing and calculates the DTW distance for all shots from shot number 1 to shot number N of measurement sensor A in step S1108. That is, the similarity calculation unit 802 calculates the similarity for each shot region. Similarly, the similarity calculation unit 802 calculates the DTW distance for all shots from shot number 1 to shot number N for D2TB(N) and D2NB(N) of measurement sensor B, D2TC(N) and D2NC(N) of measurement sensor C, and D2TD(N) and D2ND(N) of measurement sensor D by parallel processing.

[0063] In step S1108, the numerical value in the upper part of Figure 13(B) is calculated as the DTW distance. That is, the similarity calculation unit 802 calculates the DTW distance for each shot for each measurement sensor. Note that the DTW distance values ​​shown in Figure 13 are simplified for illustrative purposes, and the calculated DTW distance may be transformed into a more manageable value by normalization or other means.

[0064] In step S1109, the abnormality determination unit 801 determines an abnormality using a predetermined threshold value for the DTW distance calculated in step S1108. In this embodiment, the threshold value for the exposure period is set to 5. If the value of the DTW distance is greater than the threshold value, the exposure device 100 is determined to be in an abnormal state. If the value of the DTW distance is less than or equal to the threshold value, the exposure device 100 is determined to be in a normal state. In step S1109, as shown in the lower part of Figure 13(B), the determination result for each shot is obtained for each measurement sensor. In Figure 13(B), all DTW distances are less than or equal to the threshold value. Therefore, all abnormality detection results during the exposure period are normal determination results, and the abnormality determination unit 801 determines that the exposure device 100 is not abnormal.

[0065] In step S1110, if all the judgment results obtained in step S1109 are normal (No), the process proceeds to step S1111. The abnormality detection unit 23 then notifies the control unit 20 that the exposure device 100 is in a normal state, and the control unit 20 performs a predetermined operation and terminates the process. On the other hand, if any of the judgment results obtained in step S1109 are abnormal for any of the measurement sensors or shot numbers (Yes), the process proceeds to step S1112. The abnormality detection unit 23 then notifies the control unit 20 that the exposure device 100 is in an abnormal state, and the control unit 20 performs a predetermined operation and terminates the process.

[0066] In the above-described flow, as an example, in step S1105, if all judgment results during the setting period are judged as normal, the abnormality detection flow for the exposure period (steps S1106 to S1110) is executed. However, if necessary, step S1105 may be skipped, and in S1110, it may be determined whether an abnormality was detected in either the setting period or the exposure period. In this case, regardless of whether there was an abnormality in the setting period, the abnormality detection process for the exposure period will be performed, making it possible to detect both abnormalities caused by the setting period and abnormalities caused by the exposure period. As a result, the accuracy of detecting abnormalities in the exposure apparatus 100 can be further improved, and it can also serve as a clue for investigating the cause of the abnormality.

[0067] As described above, even if no abnormality is detected during the exposure period, by using data from the settling period, which is the exposure preparation period, it is possible to capture changes that differ from those during normal operation, thereby improving the abnormality detection accuracy of the exposure apparatus 100.

[0068] In this embodiment, the processing from shot number 1 to shot number N was performed in parallel. However, for example, the processing from shot number 1 to shot number N may be performed sequentially (i.e., the process of repeating steps S1101 to S1105 of the adjustment period and steps S1106 to S1110 of the exposure period for the number of shots). In this case, if an abnormality is detected at shot number N, the process may be modified to provide feedback to the next shot number, such as stopping the exposure of shot number N+1 or performing a correction process according to the abnormality. Specifically, for example, if an abnormality is detected at shot number N, when exposing shot numbers N+1 and beyond, the drive profiles of the master plate stage 13 and the substrate stage 16 may be adjusted to mitigate the abnormal state according to the sensor that detected the abnormality.

[0069] Furthermore, in this embodiment, anomalies are detected using waveform similarity for data that have similar waveform shapes during normal operation. However, this method may be modified to detect anomalies using statistical methods or machine learning depending on the characteristics of each sensor.

[0070] In the above-described embodiment, the case where the method is applied to a scanning exposure apparatus employing a step-and-scan method was explained, but it is also possible to apply the above-described abnormality detection process to an exposure apparatus using a step-and-repeat method. When applied to an exposure apparatus using a step-and-repeat method, only the measurement data of the substrate stage 16 may be used.

[0071] <Embodiment of Article Manufacturing Method> The method for manufacturing articles in the embodiments of the present invention is suitable for manufacturing articles such as flat panel displays, liquid crystal display elements, semiconductor elements, and MEMS. This manufacturing method includes the steps of exposing a substrate coated with a photosensitive material using the exposure apparatus 100 (exposure process) described above, and developing the exposed photosensitive material. Furthermore, an etching process or ion implantation process is performed on the substrate using the pattern of the developed photosensitive material as a mask to form a circuit pattern on the substrate. These processes of exposure, development, etching, etc., are repeated to form a circuit pattern consisting of multiple layers on the substrate. In a subsequent process, dicing (processing) is performed on the substrate on which the circuit pattern has been formed, followed by chip mounting, bonding, and inspection processes. This manufacturing method may also include other well-known processes (oxidation, film formation, vapor deposition, doping, planarization, resist peeling, etc.). The method for manufacturing articles in this embodiment is advantageous compared to conventional methods in at least one of the performance, quality, productivity, and production cost of the articles.

[0072] <Other Embodiments> Although preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of its gist.

[0073] 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 storage medium, and by having one or more processors in the computer of that system or device read and execute the program. It can also be realized by a circuit (e.g., an ASIC) that implements one or more functions.

[0074] This embodiment includes the following configuration. (Composition 1) An exposure apparatus for exposing multiple shot areas on a substrate via a master plate, A master plate stage for holding the aforementioned master plate, A substrate stage for holding the aforementioned substrate, A measuring unit for measuring the operating state of at least one of the original plate stage and the substrate stage, The system includes an abnormality detection unit that detects abnormalities in the exposure apparatus based on the measurement data from the measurement unit, The exposure apparatus is characterized in that the abnormality detection unit detects the abnormality using the measurement data from the exposure preparation period, during the non-exposure period in which the shot area is not exposed, in which the acceleration of the original plate stage or the substrate stage is similar to that of the exposure period in which the shot area is exposed. (Configuration 2) The exposure apparatus according to configuration 1, characterized in that the abnormality detection unit calculates the similarity between the measurement data during the exposure preparation period and reference data obtained from the measurement unit of a normal exposure apparatus, and detects the abnormality based on the similarity. (Composition 3) The system comprises multiple measurement units, The exposure apparatus according to configuration 2, characterized in that the abnormality detection unit calculates the similarity for each of the measurement data obtained from the plurality of measurement units. (Composition 4) The measurement data is obtained for each of the multiple shot regions, The exposure apparatus according to configuration 2 or 3, characterized in that the abnormality detection unit calculates the similarity for each of the plurality of shot regions. (Composition 5) The exposure apparatus according to configuration 4, characterized in that the abnormality detection unit performs a predetermined operation in the exposure process for the next shot region following the shot region in which the abnormality was detected, according to the measurement data of the shot region in which the abnormality was detected. (Composition 6) The exposure apparatus according to configuration 4, characterized in that the abnormality detection unit calculates the similarity for each of the plurality of shot regions in parallel processing. (Composition 7) The exposure apparatus according to any one of configurations 2 to 6, characterized in that the abnormality detection unit determines that an abnormality has been detected when the similarity is lower than a threshold. (Composition 8) The exposure apparatus according to any one of configurations 2 to 7, characterized in that the similarity is calculated using a dynamic time stretching method. (Composition 9) The exposure apparatus according to any one of configurations 1 to 8, characterized in that when the abnormality detection unit detects the abnormality, it corrects the drive profile that defines the drive of the master plate stage or the substrate stage according to the measurement data. (Composition 10) The exposure apparatus according to any one of configurations 1 to 9, characterized in that the exposure preparation period is a period within the non-exposure period before the start of exposure, during which the acceleration of the master plate stage or the substrate stage is substantially the same as that of the exposure period. (Composition 11) The exposure apparatus according to any one of configurations 1 to 10, characterized in that the exposure preparation period is a period within the non-exposure period before the start of exposure, during which the acceleration of the master plate stage or the substrate stage is 0 or close to 0. The exposure apparatus described above. (Composition 12) The exposure apparatus according to any one of configurations 1 to 11, characterized in that the measurement data includes data measuring the displacement of the original plate stage or the substrate stage from a reference position, or the deviation of the original plate stage or the substrate stage. The exposure apparatus described above. (Composition 13) The exposure apparatus according to any one of configurations 1 to 12, characterized in that the abnormality detection unit detects the abnormality using the measurement data of the exposure preparation period and the measurement data of the exposure period. The exposure apparatus described above. (Composition 14) The exposure apparatus is characterized by scanning exposure of a plurality of shot regions of the substrate, as described in any one of configurations 1 to 13. (Method 1) An abnormality detection method for an exposure apparatus that exposes multiple shot areas on a substrate via a master plate, A step of acquiring measurement data by measuring the operating state of at least one of the master plate stage that holds the master plate and the substrate stage that holds the substrate, The process includes an abnormality detection step that detects an abnormality in the exposure apparatus based on the measurement data acquired in the acquisition step, An anomaly detection method characterized in that, in the anomaly detection step, the anomaly is detected using the measurement data from the exposure preparation period during the non-exposure period in which the shot area is not exposed, and in which the acceleration of the original plate stage or the substrate stage is similar to that of the exposure period in which the shot area is exposed. (Method of manufacturing articles) A step of exposing a substrate using an exposure apparatus described in any one of configurations 1 to 14, A step of developing the exposed substrate, A process for manufacturing an article from the developed substrate, A method for manufacturing an article, characterized by having the following: [Explanation of Symbols]

[0075] 12 Original version 13 Original Stage 15 circuit boards 16 PCB Stage 18. First Measurement Unit 19. Second Measurement Unit 20 Control Unit 23 Anomaly detection unit 100 Exposure equipment

Claims

1. An exposure apparatus for exposing multiple shot areas on a substrate via a master plate, A master plate stage for holding the aforementioned master plate, A substrate stage for holding the aforementioned substrate, A measuring unit for measuring the operating state of at least one of the original plate stage and the substrate stage, The system includes an abnormality detection unit that detects abnormalities in the exposure apparatus based on the measurement data from the measurement unit, The exposure apparatus is characterized in that the abnormality detection unit detects the abnormality using the measurement data from the exposure preparation period, during the non-exposure period in which the shot area is not exposed, in which the acceleration of the original plate stage or the substrate stage is similar to that of the exposure period in which the shot area is exposed.

2. The exposure apparatus according to claim 1, characterized in that the abnormality detection unit calculates the similarity between the measurement data during the exposure preparation period and reference data obtained from the measurement unit of a normal exposure apparatus, and detects the abnormality based on the similarity.

3. The system comprises multiple measurement units, The exposure apparatus according to claim 2, characterized in that the abnormality detection unit calculates the similarity for each of the measurement data obtained from the plurality of measurement units.

4. The measurement data is obtained for each of the multiple shot regions, The exposure apparatus according to claim 2, characterized in that the abnormality detection unit calculates the similarity for each of the plurality of shot regions.

5. The exposure apparatus according to claim 4, characterized in that the abnormality detection unit performs a predetermined operation in the exposure process for the next shot region following the shot region in which the abnormality was detected, according to the measurement data of the shot region in which the abnormality was detected.

6. The exposure apparatus according to claim 4, characterized in that the abnormality detection unit calculates the similarity for each of the plurality of shot regions in parallel processing.

7. The exposure apparatus according to claim 2, characterized in that the abnormality detection unit determines that an abnormality has been detected when the similarity is lower than a threshold.

8. The exposure apparatus according to claim 2, characterized in that the similarity is calculated using a dynamic time stretching method.

9. The exposure apparatus according to claim 1, characterized in that, when the abnormality detection unit detects the abnormality, it corrects the drive profile that defines the drive of the master plate stage or the substrate stage according to the measurement data.

10. The exposure apparatus according to claim 1, characterized in that the exposure preparation period is a period within the non-exposure period before the start of exposure, during which the acceleration of the master plate stage or the substrate stage is substantially the same as that of the exposure period.

11. The exposure apparatus according to claim 1, characterized in that the exposure preparation period is a period within the non-exposure period before the start of exposure, during which the acceleration of the master plate stage or the substrate stage is 0 or close to 0.

12. The exposure apparatus according to claim 1, characterized in that the measurement data includes data measuring the displacement of the original plate stage or the substrate stage from a reference position, or the deviation of the original plate stage or the substrate stage.

13. The exposure apparatus according to claim 1, characterized in that the abnormality detection unit detects the abnormality using the measurement data of the exposure preparation period and the measurement data of the exposure period.

14. The exposure apparatus according to claim 1, characterized in that it scans and exposes a plurality of shot regions of the substrate.

15. An abnormality detection method for an exposure apparatus that exposes multiple shot areas on a substrate via a master plate, A step of acquiring measurement data by measuring the operating state of at least one of the master plate stage that holds the master plate and the substrate stage that holds the substrate, The process includes an abnormality detection step that detects an abnormality in the exposure apparatus based on the measurement data acquired in the acquisition step, An anomaly detection method characterized in that, in the anomaly detection step, the anomaly is detected using the measurement data from the exposure preparation period during the non-exposure period in which the shot area is not exposed, and in which the acceleration of the original plate stage or the substrate stage is similar to that of the exposure period in which the shot area is exposed.

16. A step of exposing a substrate using an exposure apparatus according to any one of claims 1 to 14, A step of developing the exposed substrate, A process for manufacturing an article from the developed substrate, A method for manufacturing an article, characterized by having the following:

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