Exposure apparatus control method, exposure apparatus, program, computer, and article manufacturing method

Abstract

A control method of an exposure apparatus, an exposure apparatus, a program, a computer, and an article manufacturing method are disclosed. A control method of an exposure apparatus configured to expose a substrate by projecting a pattern of a master onto the substrate under a set illumination condition through a projection optical system is provided. The method includes acquiring a first light intensity distribution formed on a pupil surface of the projection optical system when the master arranged on an object surface is illuminated under the illumination condition, and acquiring a second light intensity distribution formed when the object surface is illuminated under the illumination condition without the master. The method further includes acquiring first change information and second change information indicating changes in optical characteristics of the projection optical system affecting imaging of a pattern extending in different directions. Control data is generated by weighting the changes based on the first light intensity distribution and the second light intensity distribution, and exposure of a plurality of substrates is performed based on the control data.

Description

Technical Field

[0001] This disclosure relates to methods for controlling an exposure apparatus, exposure apparatuses, programs, computers, and methods for manufacturing articles. Background Technology

[0002] In semiconductor processes, an intermediate mask (master) is sometimes used to expose a substrate, in which a pattern extending in one direction is more dominant than a pattern extending in another direction. Because the light used to illuminate the intermediate mask produces many diffracted beams in one direction, a non-rotationally symmetric thermal distribution is formed in the projection optics system, resulting in non-rotationally symmetric exposure aberrations (hereinafter referred to as exposure astigmatism).

[0003] Exposure astigmatism is represented by the difference between FocusH, which influences the imaging of a pattern extending horizontally (e.g., the X-axis) on an intermediate mask, and FocusV, which influences the imaging of a pattern extending vertically (e.g., the Y-axis) on the intermediate mask. For example, if a substrate is exposed using an intermediate mask on which a pattern extending vertically is predominantly arranged, a non-rotationally symmetric thermal distribution is generated in the projection optics system. As a result, FocusV is generated in large quantities, while FocusH is generated in small quantities. However, to correct both FocusV and FocusH, a special configuration needs to be added to the projection optics system, resulting in high costs. It is advantageous to provide a method for correcting the average value of FocusH and FocusV using existing correction mechanisms (e.g., mechanisms that drive the wafer stage in the Z-axis direction).

[0004] A method has been proposed that involves pre-obtaining a pattern of an intermediate mask, calculating the generation direction of diffracted light from the pattern, and predicting the resulting exposure aberrations (Japanese Patent Publication No. 2019-070812). However, in this method, the generation direction of the diffracted beam and the resulting exposure aberrations are obtained through calculation, and the results may differ from the actual situation. Another method proposes measuring the diffracted light and using a pre-obtained pupil aberration map to predict exposure aberrations (Japanese Patent Publication No. 2009-218366). This method can accurately obtain the generated aberrations, but if exposure astigmatism occurs as described above, a hardware configuration for correcting this is required. Summary of the Invention

[0005] This disclosure provides a technique for correcting residuals that facilitates easy reduction of exposure aberrations.

[0006] The first aspect of this disclosure provides a method for controlling an exposure apparatus configured to expose a substrate by projecting a pattern of a master onto the substrate under set illumination conditions using a projection optics system. The control method includes: a first acquisition step, wherein the first acquisition step acquires a first light intensity distribution and a second light intensity distribution, the first light intensity distribution being formed on a pupil surface of the projection optics system when the master is disposed on an object surface of the projection optics system and the master is illuminated under the illumination conditions, and the second light intensity distribution being formed on the pupil surface when the object surface is illuminated under the illumination conditions without the master being disposed on the object surface; and a second acquisition step, wherein the second acquisition step acquires a first light intensity distribution and a second light intensity distribution. The system comprises: first change information indicating a first change, which is a change in the optical properties of the projection optical system affecting the imaging of a first pattern extending in a first direction under the illumination conditions; and second change information indicating a second change, which is a change in the optical properties of the projection optical system affecting the imaging of a second pattern extending in a second direction under the illumination conditions, the second direction being different from the first direction; a generation step, which generates control data by performing weighting based on the first light intensity distribution and the second light intensity distribution and obtaining a weighted average of the first change and the second change; and an exposure step, which performs exposure of a plurality of substrates based on the control data.

[0007] A second aspect of this disclosure provides a program stored in a medium and configured to cause a computer to execute a control method defined according to a first aspect of this disclosure.

[0008] A third aspect of this disclosure provides a computer that includes programs defined according to a second aspect of this disclosure.

[0009] A fourth aspect of this disclosure provides an exposure apparatus configured to expose a substrate by projecting a pattern of a master onto the substrate under set illumination conditions using a projection optics system. The exposure apparatus includes: a measuring device configured to acquire a first light intensity distribution and a second light intensity distribution, the first light intensity distribution being formed on a pupil surface of the projection optics system when the master is disposed on an object surface of the projection optics system and the master is illuminated under the illumination conditions, and the second light intensity distribution being formed on the pupil surface when the object surface is illuminated under the illumination conditions without the master being disposed on the object surface; and a controller configured to acquire... First change information and second change information, the first change information indicating a first change, the first change being a change in the optical properties of the projection optical system affecting the imaging of a first pattern extending in a first direction under the illumination conditions, the second change information indicating a second change, the second change being a change in the optical properties of the projection optical system affecting the imaging of a second pattern extending in a second direction under the illumination conditions, the second direction being different from the first direction, and configured to generate control data by obtaining a weighted average of the first change and the second change while performing weighting based on the first light intensity distribution and the second light intensity distribution, wherein the controller controls the exposure of a plurality of substrates based on the control data.

[0010] The fifth aspect of this disclosure provides a method for manufacturing an article, the method comprising: an exposure step of exposing a substrate using an exposure apparatus as defined in the fourth aspect of this disclosure; and a processing step of processing the substrate that has undergone the exposure step, thereby obtaining an article.

[0011] The features of this disclosure will become clear from the following description of embodiments with reference to the accompanying drawings. The following description of embodiments is given by way of example. Attached Figure Description

[0012] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the embodiments.

[0013] Figure 1 This is a schematic cross-sectional view showing the configuration of the exposure apparatus EX according to an embodiment;

[0014] Figure 2A This is a view showing the state of the exposure apparatus when measuring the angular distribution of light along the optical axis entering the image plane of the projection optics system under intermediate mask illumination;

[0015] Figure 2BThis is a view showing the state of the exposure apparatus when measuring the angular distribution of light entering a position separated from the optical axis of the image plane of the projection optics system during intermediate mask illumination;

[0016] Figure 3 This is a schematic diagram illustrating an example of the configuration of the measuring equipment;

[0017] Figure 4 It is a view showing the relationship between the position of the image along the optical axis and the amount of light in the space-time measurement;

[0018] Figure 5 This is a flowchart illustrating the method for predicting the optical characteristics of a projection optics system, specifically FocusH and FocusV.

[0019] Figure 6 This is a view illustrating the results of predicting the generation amounts of FocusH and FocusV during an exposure operation;

[0020] Figure 7 This is a view illustrating FocusH and FocusV corrected based on the FocusAve aberration prediction model;

[0021] Figure 8 This is a view that illustrates multiple measurement areas of the intermediate mask;

[0022] Figure 9 This is a view illustrating the light intensity distribution formed on the pupil surface of the projection optics system by each measurement in one of the multiple measurement regions on the intermediate mask;

[0023] Figure 10 This is an example of using... Figure 9 The image shows a view of the light intensity distribution obtained by averaging the measurement results.

[0024] Figure 11A This is a view showing the state of an exposure apparatus when measuring the angular distribution of light along the optical axis of the image plane of a projection optical system while the object surface is illuminated, without an intermediate mask being placed on the object surface.

[0025] Figure 11B This is a view showing the state of an exposure apparatus when measuring the angular distribution of light entering a position separated from the optical axis of the image plane of the projection optical system while illuminating the object surface without an intermediate mask being placed on the object surface.

[0026] Figure 12A It is a view illustrating the results of measuring the light intensity distribution formed on the pupil surface of the projection optics system when illuminating the object surface at multiple points on the image plane without placing an intermediate mask on the object surface;

[0027] Figure 12B This is a view illustrating the light intensity distribution (b) obtained by averaging the results of measuring the light intensity distribution formed on the pupil surface of the projection optics system when illuminating the object surface without placing an intermediate mask at multiple points on the image plane.

[0028] Figure 13 This is a view illustrating a first light intensity distribution (solid line) and a second light intensity distribution (dashed line). The first light intensity distribution is formed on the pupil surface of the projection optical system when an intermediate mask is arranged on the object surface of the projection optical system, and the second light intensity distribution is formed on the pupil surface of the projection optical system when the object surface of the projection optical system is illuminated without an intermediate mask being arranged on the object surface of the projection optical system.

[0029] Figure 14 This is a view illustrating the amount of exposure aberration generated and the fitting results;

[0030] Figure 15 This is a view illustrating the results of exposure aberration correction;

[0031] Figure 16 This is a view illustrating another correction result for exposure aberrations;

[0032] Figure 17 This is a view illustrating a first light intensity distribution (solid line) and a second light intensity distribution (dashed line). The first light intensity distribution is formed on the pupil surface of the projection optical system when an intermediate mask is arranged on the object surface of the projection optical system and the intermediate mask is illuminated. The second light intensity distribution is formed on the pupil surface of the projection optical system when the object surface of the projection optical system is illuminated without an intermediate mask being arranged on the object surface of the projection optical system.

[0033] Figure 18 This is an example of what happens when it is used. Figure 17 The results shown are views of FocusAve, FocusH, and FocusV of the intermediate mask used to expose a batch of wafers.

[0034] Figure 19 This is a view illustrating the changes in FocusAve, FocusH, and FocusV caused by the calibration; and

[0035] Figure 20 This is a view illustrating a control method according to an embodiment. Detailed Implementation

[0036] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. It should be noted that the following embodiments are not intended to limit the scope of the claims. Several features are described in the embodiments, but not all such features are necessary, and multiple such features can be appropriately combined. Furthermore, in the drawings, the same reference numerals are given the same or similar configuration, and redundant descriptions are omitted.

[0037] Figure 1 This is a schematic cross-sectional view illustrating the configuration of the exposure apparatus EX according to an embodiment. The exposure apparatus EX is a photolithography apparatus used in the manufacturing process of articles such as semiconductor devices to form patterns on a wafer (substrate). In this embodiment, the exposure apparatus EX is a step-scan type exposure apparatus (scanner) that exposes the wafer 11 (scan-exposure) and transfers the pattern of the intermediate mask 8 to the wafer 11 while moving the intermediate mask 8 and the wafer 11 in the scanning direction. However, the exposure apparatus EX may also employ a step-repeat method or another exposure method.

[0038] like Figure 1 As shown, the exposure apparatus EX may include a forming optical system 2 that shapes light from a light source 1 into a predetermined shape, an illumination optical system 4 that illuminates an intermediate mask 8 (original) using light shaped by the forming optical system 2, and a projection optical system 10 that projects the pattern of the intermediate mask 8 onto a wafer 11 (substrate). The exposure apparatus EX may also include an intermediate mask stage 9 that moves while holding the intermediate mask 8, a wafer stage 12 that moves while holding the wafer 11, and a controller 13. The exposure apparatus EX may also include a measuring device 14 that measures the angular distribution of light entering the surface of the wafer 11 (the image plane of the projection optical system 10), and a processing unit 15 that processes the angular distribution measured by the measuring device 14. The light source 1 includes, for example, an ArF excimer laser with a wavelength of 193 nm or a KrF excimer laser with a wavelength of 248 nm, and emits light (exposure light) for illuminating the intermediate mask 8. The light source 1 may include an ultra-high pressure mercury vapor lamp or an LED (light-emitting diode). The shaping optical system 2 internally includes diffractive optical elements, prisms, a zoom lens unit, and an aperture stop (all not shown), and shapes the light from the light source 1 such that a light intensity distribution (pupil intensity distribution) with a target shape, such as a circular shape, a ring shape, or a quadrupole shape, is obtained on the pupil surface of the illumination optical system 4. Each of the diffractive optical elements, prisms, and aperture stops can be configured such that any one of a plurality of candidates can be selected by a switching mechanism such as a turntable. Additionally, the aperture stop can be a variable aperture with a variable opening diameter. The shaping optical system 2 may include an optical integrator 3, and light can exit from the optical integrator 3 toward the illumination optical system 4. The shaping optical system 2 is not limited to the above example and may have another configuration.

[0039] The illumination optical system 4 is an optical system that illuminates the intermediate mask 8 using light emitted from the optical integrator 3, and may include a converging lens 5, a field stop 6, and an imaging optical system 7. The optical integrator 3 may be a wavefront-splitting type optical integrator, such as a compound eye lens. The converging lens 5 of the illumination optical system 4 includes multiple optical components (such as lenses and mirrors), and illuminates the field stop 6 using light emitted from the optical integrator 3 through Kohler illumination. The exit surface of the optical integrator 3 is conjugate to the pupil surface of the illumination optical system 4, and the numerical aperture (NA) of the illumination optical system 4 can be changed by altering the magnitude of the light intensity distribution formed on the exit surface of the optical integrator 3. The ratio (NAIL NAPO) of the numerical aperture (NAIL) of the illumination optical system 4 to the numerical aperture (NAPO) of the projection optical system 10 can be referred to as the coherence factor (σ value). This σ value is an important value that determines the resolution of the pattern projected onto the wafer 11.

[0040] The configuration of the optical integrator 3 and the illumination optical system 4 is not limited to the configurations described above. For example, the optical integrator 3 can be an internal reflection type optical integrator such as an optical rod. If the optical integrator 3 is an optical rod, the illumination optical system 4 can replace the converging lens 5 and include an image of the illumination distribution formed on the exit surface of the optical rod on the field stop 6, that is, an imaging optical system that illuminates the field stop 6 by critical illumination. Alternatively, the field stop 6 can be arranged near the exit surface of the optical rod. The imaging optical system 7 is an optical system that includes multiple optical components (such as lenses and mirrors) and forms an image of the field stop 6 on an intermediate mask 8 arranged on the target illumination surface (the object surface of the projection optical system 10) of the illumination optical system 4. The field stop 6 is arranged to define the illumination range of the intermediate mask 8 held by the intermediate mask stage 9 and can be scanned synchronously with the intermediate mask stage 9 and the wafer stage 12.

[0041] The projection optical system 10 includes multiple optical components (such as lenses and mirrors) and projects the pattern of the intermediate mask 8 onto the wafer 11. The projection optical system 10 can be a refractive optical system, a reflective optical system, or a catadioptric optical system. The resolution of the pattern projected onto the wafer 11 depends on the numerical aperture of the projection optical system 10 and the light intensity distribution (or σ value) on the pupil surface of the projection optical system 10. The aperture stop 103 is an aperture stop arranged on the pupil surface of the projection optical system 10 with a variable opening diameter, and determines the numerical aperture of the projection optical system 10. The intermediate mask 8 is arranged on the object surface of the projection optical system 10, and the wafer 11 is arranged on the image plane of the projection optical system 10. The controller 13 controls the units of the exposure apparatus EX, thereby controlling the scanning exposure of the wafer 11. The controller 13 can be formed by, for example, a programmable logic device (PLD) such as a field-programmable gate array (FPGA), an application-specific integrated circuit (ASIC), a general-purpose or special-purpose computer with a program installed thereon, or some or all of these.

[0042] In the exposure apparatus EX, during scanning exposure, light emitted from the light source 1 illuminates the intermediate mask 8 held by the intermediate mask stage 9 via the forming optics system 2 and the illumination optics system 4. The pattern of the intermediate mask 8 illuminated by the illumination optics system 4 is projected onto the wafer 11 held by the wafer stage 12 by the projection optics system 10 (forming an image). By scanning the intermediate mask 8 and the wafer 11 at a speed ratio according to the projection magnification of the projection optics system 10, the pattern of the intermediate mask 8 can be transferred onto the wafer 11.

[0043] The measuring device 14 is arranged on the wafer stage 12 and measures the angular distribution of light entering the surface of the wafer 11, that is, the image plane of the projection optical system 10. Figure 2A The diagram illustrates the state of the exposure apparatus EX when measuring the angular distribution of the beam entering the image plane of the projection optics system 10 along its optical axis. The wafer stage 12 is positioned such that the pinhole 141 of the measuring device 14 disposed on the wafer stage 12 is located on the image plane of the projection optics system 10 along its optical axis. The measuring device 14 includes a light receiving unit 142 disposed at a distance d from the pinhole 141 in the -Z-axis direction. The light receiving unit 142 is a photoelectric conversion element such as a CCD or CMOS, and preferably a two-dimensional image sensor.

[0044] The light that has entered the pinhole 141 arranged on the image plane enters the light receiving surface of the light receiving unit 142, which is arranged at a distance d away from the pinhole 141, at position r. Since r = d tanθ, the angular distribution of the light entering the pinhole 141 on the image plane can be measured based on the position of the light entering the light receiving surface. The angular distribution depends on the light intensity distribution on the aperture stop 103 of the projection optical system 10, that is, on the pupil surface. Therefore, the measurement depends on the distribution of light intensity on the pupil surface of the projection optical system 10. Since the pupil surface and the image plane of the projection optical system 10 maintain an orthogonal projection relationship, the light intensity distribution on the pupil surface of the projection optical system 10 can be obtained by converting the tanθ distribution coordinates measured by the light receiving unit 142 into a sinθ distribution. The coordinate transformation process is performed by the processing unit 15, thereby obtaining the light intensity distribution on the pupil surface of the projection optical system 10, that is, the exit pupil light intensity distribution.

[0045] Figure 2B The state of the exposure apparatus EX is shown when measuring the angular distribution of light entering a position separated from the optical axis of the image plane of the projection optical system 10. The wafer stage 12 is positioned such that the pinhole 141 of the measuring device 14 arranged on the wafer stage 12 is located outside the optical axis of the image plane of the projection optical system 10, and the angular distribution of light entering the image plane is measured by the measuring device 14. The exit pupil light intensity distribution at the position separated from the optical axis of the image plane of the projection optical system 10 can be obtained by performing coordinate transformation on the measured angular distribution by the processing unit 15.

[0046] The example of pinhole 141 arranged on the image plane of the projection optical system 10 has been described above. However, this disclosure is not limited thereto, and the pinhole can also be arranged on the intermediate mask 8 side. That is, a pinhole pattern can be arranged on the intermediate mask 8 instead of the pinhole 141 formed on the measuring device 14. Alternatively, a plate of the same material and thickness as the intermediate mask can be arranged on the intermediate mask stage 9, and a pinhole pattern can be arranged on the plate. If the pinhole is arranged on the intermediate mask 8 side (the object surface side of the projection optical system 10), the wafer stage 12 is driven such that the center or reference point of the light receiving unit is positioned at the image plane position of the angular distribution to be measured. In addition, the intermediate mask stage 9 is driven such that the intermediate mask-side pinhole is positioned on the intermediate mask surface at a position corresponding to the center or reference point of the light receiving unit. Measurement can be performed in this state. The pinhole can be arranged on both the image plane side and the intermediate mask side.

[0047] Incidentally, in order to obtain the intensity distribution of the exit pupil light of the projection optical system 10 more directly, such as Figure 3As shown, a Fourier transform optical system 143 can be provided in the measuring device 14. The image plane (or pinhole 141) of the projection optical system 10 is arranged on the front focal plane of the Fourier transform optical system 143, and the light receiving unit 142 is arranged on the back focal plane of the Fourier transform optical system 143. The Fourier transform optical system 143 is an orthogonal projection optical system with a focal length f, and the light arrival position r = f sinθ relative to the position r of the light receiving unit 142. That is, since the light receiving unit 142 is conjugate to the pupil surface of the projection optical system 10, the light intensity distribution of the exit pupil of the projection optical system 10 can be measured more directly by the measuring device 14.

[0048] Next, a method for measuring the optimal focal position of the projection optical system 10 will be described. An intermediate mask reference plate 105, different from the intermediate mask 8, is arranged on the intermediate mask stage 9, and intermediate mask side markers 113 for measuring the aerial image can be arranged on the intermediate mask reference plate 105. The intermediate mask side markers 113 can have a line-and-space pattern with multiple lines arranged periodically. Furthermore, a detection plate 112 is arranged on the wafer stage 12, and wafer side markers 114 for measuring the aerial image can be arranged on the detection plate 112. The wafer side markers 114 can have a line-and-space pattern with multiple lines arranged periodically with the same periodic projection magnification as the intermediate mask side. Additionally, a photodetector 115 can be arranged below the detection plate 112. The lines of the line-and-space patterns of the intermediate mask side markers 113 and wafer side markers 114 are formed of, for example, chromium films, and the spacing can be formed by gaps between chromium films.

[0049] When measuring the optimal focal position, firstly, the intermediate mask stage 9 is positioned such that the intermediate mask side mark 113 on the intermediate mask reference plate 105 is illuminated by light emitted from the light source 1 via the illumination optics system 4. Then, the intermediate mask side mark 113 on the intermediate mask reference plate 105 is illuminated by light emitted from the light source 1 via the illumination optics system 4. The light used to illuminate the line and spacing pattern of the intermediate mask side mark 113 is diffracted by the line and spacing pattern and enters the projection optics system 10. The light that has entered the projection optics system 10 passes through the aperture stop 103 arranged on the pupil surface of the projection optics system 10. At this point, higher-order diffracted light is blocked, and the remaining 0th-order and lower-order diffracted beams reach the image plane of the projection optics system 10. The light that has reached the image plane of the projection optics system 10 passes through the line and spacing pattern of the wafer side mark 114 arranged on the detection plate 112 on the wafer stage 12 and is received by the photodetector 115. The image of the lines and spacing pattern of the intermediate mask side mark 113 is reduced and projected according to the projection magnification of the projection optics system 10, and projected onto the lines and spacing pattern on the wafer side mark 114. If the wafer stage 12 is scanned and driven in the optical axis direction (Z-axis direction) in the reduced projection state, the reduced projected image of the intermediate mask side mark 113 overlaps with the wafer side mark 114 at the optimal focal position of the projection optics system 10. Therefore, the amount of light received by the photodetector 115 is maximum at the optimal focal position. As the optimal focal position is deviated from, the contrast of the reduced projected image of the intermediate mask side mark 113 on the wafer side mark 114 on the detection plate 112 decreases, and the image becomes blurry; therefore, the amount of light received by the photodetector 115 gradually decreases.

[0050] Figure 4 The focal curve is shown, obtained by scanning and driving the wafer stage 12 in the Z-axis direction while clamping the optimal focal position, with the intermediate mask-side mark 113 scaled down and projected onto the wafer-side mark 114. Figure 4 In the diagram, the horizontal axis indicates the position *int* along the optical axis (Z-axis direction), and the vertical axis indicates the amount of light measured by the photodetector 115. The focal curve is an upward-sloping curve, and the position where the curve peaks is the optimal focal position. The method for measuring the optimal focal position described here is merely an example, and the optimal focal position can be measured by another method. Note that measuring the optimal focal position is also called focal measurement.

[0051] To measure astigmatism, lines and spacing patterns in the X-axis and Y-axis directions can be arranged on both the intermediate mask-side mark 113 and the wafer-side mark 114. Here, the lines and spacing patterns in the X-axis direction are examples of patterns extending in the X-axis direction (first direction), and the lines and spacing patterns in the Y-axis direction are examples of patterns extending in the Y-axis direction (second direction), which is different from the X-axis direction. The X-axis and Y-axis directions are orthogonal to each other. With the lines and spacing patterns in the X-axis and Y-axis directions of the intermediate mask-side mark 113 reduced and projected onto the wafer-side mark 114, the wafer stage 12 is scanned and driven in the Z-axis direction within a range that includes the optimal focal position for both the lines and spacing patterns in the X-axis and Y-axis directions. Thus, the focal curves of the lines and spacing patterns in the X-axis and Y-axis directions are obtained. The controller 13 calculates the optimal focal position where the peak of the obtained focal curves of the lines and spacing patterns in the X-axis and Y-axis directions is present. The optimal focus of the line and spacing pattern in the X-axis direction will be represented as FocusV, and the optimal focus position of the line and spacing pattern in the Y-axis direction will be represented as FocusH. Controller 13 can also obtain the difference between FocusH and FocusV as astigmatism. The average of FocusH and FocusV will be represented as FocusAve.

[0052] Below, we will refer to Figure 5 A method for predicting FocusH and FocusV, which are optical characteristics of the projection optical system 10, is described. In step S1-1, the controller 13 starts the exposure operation and transports the intermediate mask 8 to the intermediate mask stage 9. Also in step S1-1, the controller 13 transports the wafer 11 to the wafer stage 12. Next, in step S1-2, before the exposure of the wafer 11 begins, the controller 13 measures FocusH and FocusV under the illumination conditions (illumination mode) used for exposure. Here, illumination conditions refer to the effective light source distribution (in other words, the light intensity distribution on the pupil surface of the illumination optical system 4). In step S1-3, the controller 13 performs the exposure of the Nth wafer 11 in the batch. In step S1-4, the controller 13 determines whether the exposure of the last wafer 11 in the batch is complete. After determining that the exposure of the last wafer 11 is complete, the operation ends in step S1-5. Otherwise, steps S1-2 and S1-3 are repeated.

[0053] When the FocusH and FocusV measured by the above method are fitted to the aberration prediction model represented by equations (1), (2), and (3), the changes in FocusH and FocusV during the exposure operation can be predicted. Note that fitting the model and generating the model mean that the parameter values ​​of the model are determined by fitting. Φ is the amount of FocusH generated by the model, and N in the suffix indicates the measurement timing of FocusH. In this specification, a model including three time constants K is used. m Prediction model parameters P (m=1, 2, 3) m (m=1, 2, 3). Prediction model parameters P m The value indicates the saturation level of FocusH. `m` indicates the model number, and in this specification, `m=1` is the long-term time constant model, `m=2` is the medium-term time constant model, and `m=3` is the short-term time constant model. `α` indicates the exposure load, which takes different values ​​depending on the exposure conditions. The exposure load α is represented as a function of the transmittance R of the intermediate mask, the exposure amount D, the size of the injection area A, the number of injection areas Num to be exposed between the FocusH measurement and the next FocusH measurement, and the time T during this period. The exposure load can be calculated using other parameters such as the reflectivity of the resist. The variables used in the fitting are the predictive model parameters, which are values ​​specific to this job. For FocusV, the same exposure aberration model fitting is performed as for FocusH.

[0054] Furthermore, FocusAve is predicted in advance using an aberration prediction model represented by equations (1), (2), and (3), and FocusAve is corrected during the execution of the exposure operation by driving the wafer stage 12 in the Z-axis direction. For the measurements of FocusH and FocusV, since the correction residual from FocusAve is measured, the generation amounts of FocusH and FocusV can be calculated based on the measurements of FocusH and FocusV and the correction amount of FocusAve.

[0055] ...(1)

[0056] ...(2)

[0057] ...(3)

[0058] Here, for FocusH, let P 1h P 2h and P 3h The prediction model parameters Pm (m=1, 2, 3) are determined through fitting. Additionally, for FocusV, let P... 1v P2v and P 3v The prediction model parameters Pm (m=1, 2, 3) are determined through fitting.

[0059] Figure 6 An example is shown illustrating the results of predicting the generation amounts of FocusH and FocusV during the execution of an exposure job. Figure 6 In the graph, the horizontal axis indicates the wafer number, and the vertical axis indicates the generation amount of FocusH and FocusV. Circles indicate changes in the generation amount of FocusH, and triangles indicate changes in the generation amount of FocusV. Figure 6 In the diagram, the solid and dashed lines indicate the FocusH and FocusV predicted using the exposure aberration prediction model, respectively. The controller 13 can generate the aberration prediction model based on measurements obtained during exposure operations, and when performing exposure operations with the same conditions, it uses the aberration prediction model to predict the generation amounts of FocusH, FocusV, and FocusAve. The predicted FocusAve can be corrected by driving the wafer stage 12. Figure 7 Examples of FocusH and FocusV based on the aberration prediction model correction of FocusAve are shown.

[0060] Below, we will refer to Figure 20 This describes the control method of the exposure apparatus EX or the exposure method in the exposure apparatus EX according to this embodiment. Figure 20 The processing shown is controlled by controller 13. Controller 13 can also be understood as a control device for controlling the exposure apparatus EX. Controller 13 can be configured by installing programs in a computer.

[0061] In step S2-1, controller 13 starts the exposure operation and transports the intermediate mask 8 to the intermediate mask stage 9. Additionally, in step S2-1, controller 13 transports the wafer 11 to the wafer stage 12. In step S2-2, controller 13 sets the illumination conditions specified by the exposure operation (i.e., the illumination conditions used for exposure). The illumination conditions can be set by controlling the forming optics system 2. The set illumination conditions are maintained at least until the exposure operation is completed.

[0062] In steps S2-3, the controller 13 acquires the first light intensity distribution formed on the pupil surface of the projection optical system 10 when the intermediate mask 8 is illuminated under set illumination conditions. The first light intensity distribution formed on the pupil surface of the projection optical system 10 can be acquired according to the method described with reference to FIG2. Here, the aberrations of the projection optical system 10 caused by exposure are not affected by a portion of the exposed area of ​​the intermediate mask 8, but by the entire patterned area of ​​the intermediate mask 8. Therefore, when acquiring the first light intensity distribution, it is preferable to consider the entire patterned area of ​​the intermediate mask 8. For this reason, as... Figure 8 As shown, preferably, the light intensity distribution formed on the pupil surface of the projection optics system 10 by diffracted light from, for example, each of 25 measurement regions 202, is measured, such that these represent the entire exposure area 201 of the intermediate mask 8. Regarding the Y-axis direction (scanning direction), the selection of the measurement region 202 can be performed by moving the intermediate mask stage 9. Regarding the X-axis direction (the direction orthogonal to the scan direction), the selection of the measurement region 202 can be performed by moving the wafer stage 12 to each of five points.

[0063] Figure 9 The example illustrates the result of a first light intensity distribution formed by the diffracted light from the measurement region 202 on the pupil surface of the projection optics system 10 for each of the 25 measurement regions 202 on the intermediate mask. Note that the number of measurement regions 202 on the intermediate mask 8 is not limited to 25 and can be any number. For example... Figure 10 As illustrated, the controller 13 averages the first light intensity distribution formed by the diffracted beams from 25 measurement regions 202, thereby generating an average light intensity distribution.

[0064] In steps S2-4, as Figure 11A and 11B As shown, the controller 13 acquires the second light intensity distribution formed on the pupil surface of the projection optical system 10 when the object surface of the projection optical system 10 is illuminated under set illumination conditions without using the intermediate mask 8. The second light intensity distribution formed on the pupil surface of the projection optical system 10 can also be acquired according to the method described with reference to FIG2. Without using the intermediate mask 8, the second light intensity distribution formed on the pupil surface of the projection optical system 10 does not change even if the intermediate mask stage 9 moves in the Y-axis direction. Therefore, in steps S2-4, the controller 13 acquires the second light intensity distribution of each of the five points in the X-axis direction (the same positions on the wafer stage 12 when the five measurement areas 202 arranged on the intermediate mask 8 in the X-axis direction are measurement targets). Figure 12AThis example illustrates the results of measuring the second light intensity distribution formed on the pupil surface of the projection optics system 10 when illuminating an object surface at multiple points on the image plane, without an intermediate mask 8 placed on the object surface. For example... Figure 12B As illustrated, controller 13 pairs Figure 12A The average of the five second light intensity distributions shown is used to generate the average light intensity distribution.

[0065] Steps S2-3 and S2-4 correspond to the first acquisition step, which acquires the first light intensity distribution formed on the pupil surface of the projection optical system 10 under illumination conditions set using the intermediate mask 8, and the second light intensity distribution formed on the pupil surface of the projection optical system 10 under illumination conditions set without using the intermediate mask 8.

[0066] In steps S2-5, controller 13, according to reference Figure 5 The described method measures FocusH and FocusV, and determines P. 1h P 2h、 P 3h P 1v P 2v and P 3v In other words, controller 13 uses a pattern (lines and spacing patterns in the X-axis direction) extending in the X-axis direction (first direction) to measure FocusH and performs a process of fitting the prediction model to the result, thereby determining the prediction model parameters P. 1h P 2h and P 3h Additionally, controller 13 measures FocusV using a pattern (lines and spacing patterns in the Y-axis direction) extending in the Y-axis direction (second direction) and performs a prediction model fitting to the result, thereby determining the prediction model parameters P. 1v P 2v and P 3v . Figure 14 The results are illustrated. In the example, P 1h =239.9、P 2h =-203.3、P 3h =721.7、P 1v =-177.2、P 2v =13.3 and P 3v =-780.2. From the prediction model parameter P 1h P 2h and P 3h The predicted model for FocusH indicates a first change, which is a change in the optical properties of the projection optics system 10 that affects the imaging of a pattern extending in the X-axis direction (first direction). This change is determined by the predicted model parameter P. 1v P2v and P 3v The predicted model of FocusV is a second change information indicating a second change, which is a change in the optical properties of the projection optical system 10 that affects the imaging of the pattern extending in the Y-axis direction (second direction). Step S2-5 is a second acquisition step for acquiring the first change information and the second change information.

[0067] In steps S2-6, the controller 13 obtains a weighted average of the first and second changes by performing weighting based on the first and second light intensity distributions, thereby generating control data to reduce the impact of changes in the optical characteristics of the projection optical system 10. First, the method of performing weighting based on the first and second light intensity distributions will be described exemplarily. Figure 13 In the diagram, the solid line indicates the following example: a first light intensity distribution formed on the pupil surface of the projection optical system 10 when an intermediate mask 8 is arranged on the object surface of the projection optical system 10 and illuminated under set illumination conditions. Furthermore, in Figure 13 In the image, the following example is indicated by the dashed line: a second light intensity distribution formed on the pupil surface of the projection optical system 10 when the object surface of the projection optical system 10 is illuminated under set illumination conditions without an intermediate mask 8 being disposed on the object surface of the projection optical system 10.

[0068] The second light intensity distribution (without intermediate mask 8), indicated by the dashed line, has a maximum X-axis magnitude (X'). The first light intensity distribution (with intermediate mask 8), indicated by the solid line, has a maximum X-axis magnitude (X'). Furthermore, the second light intensity distribution (without intermediate mask 8), indicated by the dashed line, has a maximum Y-axis magnitude (Y'). The first light intensity distribution (with intermediate mask 8), indicated by the solid line, has a maximum Y-axis magnitude (Y'). Here, RX = X' / X and RY = Y' / Y are defined as ratios.

[0069] exist Figure 13In the example shown, the ratio RX = 1.4 and the ratio RY = 1.0. A ratio RY of 1.0 means that the first light intensity distribution formed using the intermediate mask 8 is the same as the second light intensity distribution formed without the intermediate mask 8 (in the absence of the intermediate mask). In other words, a ratio RY of 1.0 means that there is no diffracted light emanating from the pattern of the intermediate mask 8 in the Y-axis direction. Therefore, a ratio RY of 1.0 indicates that the linewidth of the pattern (hereinafter referred to as the H pattern) arranged on the intermediate mask 8 to extend in the X-axis direction (horizontal direction) is thick. Furthermore, a ratio RX of 1.4 means that the light intensity distribution formed on the pupil surface of the projection optics system 10 with the intermediate mask 8 extends further in the X-axis direction compared to the case without the intermediate mask 8. In other words, a ratio RX of 1.4 means that there is some diffracted light emanating from the pattern of the intermediate mask 8 in the X-axis direction (horizontal direction). Therefore, a ratio RX of 1.4 indicates that the line width of the pattern (hereinafter referred to as the V pattern) arranged on the intermediate mask 8 to extend in the Y-axis direction (vertical direction) is fine.

[0070] Here, if the pattern has thick linewidth, the linewidth of the pattern projected onto the image plane is not sensitive to changes in the focal position. Even if the focal position deviates, the contrast degradation of the pattern projected onto the image plane is small, and the variation in the linewidth of the transferred pattern is also small. Conversely, if the pattern has thin linewidth, the linewidth of the pattern projected onto the image plane is sensitive to changes in the focal position. If the focal position deviates, the contrast degradation of the pattern projected onto the image plane is large, and the variation in the linewidth of the transferred pattern is large. Therefore, preferably, the focal position is set based on FocusV, which affects the V pattern that is sensitive to the focal position, rather than FocusH, which affects the H pattern that is not sensitive to the focal position.

[0071] Next, to eliminate the influence of the second light intensity distribution formed on the pupil surface of the projection optics system 10 without using the intermediate mask 8, the controller 13 subtracts 1.0 from RX and RY, thereby obtaining RX1=0.4 and RY1=0.0. Furthermore, the controller 13 calculates the integer ratio of RX1:RX2, thereby obtaining RX2:RY2=1:0. RX2:RY2 indicates the weights of FocusV and FocusH. RY2=0 means that the weight of FocusH is 0, that is, FocusH is not corrected at all. On the other hand, RX2=1 means that the weight of FocusV is 1.

[0072] Note that if RX = 1.8 and RY = 1.2, then RX1 = 0.8, RY1 = 0.2, and RX2:RY2 = 4:1. In this case, the weight of FocusV is 4, and the weight of FocusH is 1. This means that the focus position is corrected such that the correction residual when correcting the focus position is 1 for FocusV and 4 for FocusH.

[0073] Furthermore, if RX = 1.0 and RY = 1.0, then RX1 = 0.0, RY1 = 0.0, and RX2:RY2 = 1:1. This means that the focus position is corrected so that the correction residual of FocusV is equal to the correction residual of FocusH.

[0074] The following example illustrates the calculation of the prediction model parameters for exposure aberration: a weighted average of RX2:RY2 = 1:0. Assume that in steps S2-5, as described above, the prediction model parameters are determined to be P. 1h =239.9, P 2h =-203.3, P 3h =721.7, P 1v =-177.2, P 2v =13.3 and P 3v =-780.2.

[0075] By weighting RX2:RY2, controller 13 can determine the prediction model parameter P of FocusAve according to equations (4), (5) and (6). 1A P 2A and P 3A .

[0076]

[0077] Prediction model parameter P 1A P 2A and P 3A The FocusAve, expressed by equations (4), (5), and (6), is the control data used to control the position of the wafer stage 12 in the Z-axis direction (the optical axis direction of the projection optical system 10). The control data is generated to reduce the influence of the average value of the optimal focal position of the first pattern extending in the X-axis direction and the optimal focal position of the second pattern extending in the Y-axis direction.

[0078] Since RX2:RY2=1:0, therefore P 1A =-177.2, P 2A =13.3 and P 3A =-780.2. Figure 15The results of correcting the focus position based on the prediction model parameters are shown. It has been found that FocusV is corrected so that it does not change over time. For example, if RX2:RY2 = 4:1, then P... 1A =-83, P 2A =30.0 and P 3A =-479.8. Figure 16 The results of correcting the focal position based on the prediction model parameters are shown. Figure 15 In the middle, FocusV did not change over time, while Figure 16 In this context, FocusV changes over time. However, compared to... Figure 15 Compared to China, Figure 16 The change in FocusH over time is relatively small.

[0079] In step S2-7, the controller 13 performs the exposure step. More specifically, the controller 13 performs the exposure of multiple wafers constituting a batch while controlling the position of the wafer stage 12 in the Z-axis direction (the optical axis direction of the projection optical system 10) based on control data. In the exposure step, the controller 13 performs focus control with accompanying focus measurement on the wafer to be exposed first among the multiple wafers constituting the batch, and does not perform focus control with accompanying focus measurement on at least one of the remaining substrates. Thereafter, in step S2-8, the controller 13 ends the exposure operation.

[0080] As described above, by generating control data by simultaneously performing weighting based on the first light intensity distribution and the second light intensity distribution to obtain a weighted average of the first and second changes, the correction residuals of exposure aberrations can be easily reduced.

[0081] In the above embodiment, the saturation value, which serves as a parameter for the prediction model, is obtained by weighting the ratio of the magnitude of the light intensity distribution in the first direction (X-axis direction) to the magnitude of the light intensity distribution in the second direction (Y-axis direction) on the pupil surface of the projection optics system 10. This is merely an example, and weighting can be performed according to another method.

[0082] In the above embodiments, examples of correcting FocusH and FocusV using FocusAve have been described, but these are merely examples. For instance, FocusH can be replaced with a magnification that varies in the X-axis direction according to a linear function, FocusV can be replaced with a magnification that varies in the Y-axis direction according to a linear function, and FocusAve can be replaced with a magnification that changes isotropically in both the X-axis and Y-axis directions. In this case, the magnification of the projection optical system 10 can be corrected by driving the optical elements (lenses and mirrors) in the projection optical system 10.

[0083] As another embodiment, an example of performing focus calibration based on measurements of the light intensity distribution formed on the pupil of the projection optics system 10 by diffracted light from the pattern of the intermediate mask 8 will be described below. Here, reference will be made to... Figure 17 To describe, the Figure 17 Examples are shown of a first light intensity distribution formed on the pupil surface of the projection optics system 10 using an intermediate mask 8 and a second light intensity distribution formed on the pupil surface of the projection optics system 10 without using the intermediate mask 8. Note that in Figure 17 In the diagram, the solid line indicates the first light intensity distribution formed on the pupil surface of the projection optical system 10 using the intermediate mask 8, and the dashed line indicates the second light intensity distribution formed on the pupil surface of the projection optical system 10 without using the intermediate mask 8. Figure 17 In the example shown, RX = 1.25 and RY = 1.5. In this case, RX1:RY1 = 0.25:0.5 and RX2:RY2 = 1:2. This means that both the H-pattern and the V-pattern produce diffracted light, and the H-pattern has a greater effect on the change in focal position than the V-pattern has on the change in focal direction. In this case, preferably, the focal position is determined by assigning a larger weight to FocusH, which is affected by the focal position-sensitive H-pattern, than to FocusV, which is affected by the focal position-insensitive V-pattern.

[0084] Figure 18 The use of this method resulted in Figure 17 The results shown depict the FocusAve, FocusH, and FocusV of the intermediate mask used to expose a batch of wafers. The horizontal axis indicates the number of wafers, and the vertical axis indicates FocusAve, FocusH, and FocusV. Figure 19 The state of calibration performed before the exposure of the 16th wafer (W16) is shown. Before the exposure of the 16th wafer 11 (W16), focus measurement is performed using the aforementioned aerial image. If this results in FocusAve = -57.0, FocusH = -168.4, and FocusV = 50.8, then the correction value FocusAveComp for correcting FocusAve is given by equation (7), and FocusAveComp = -110.9. When the wafer stage 12 is driven in the Z-axis direction according to FocusAveComp = -110.9, FocusH and FocusV can be corrected in a good balance.

[0085]

[0086] Additionally, examples of correcting FocusH and FocusV using FocusAve have been described in other embodiments, but these are merely examples. For instance, FocusH could be replaced with a magnification that varies along the X-axis according to a linear function, FocusV could be replaced with a magnification that varies along the Y-axis according to a linear function, and FocusAve could be replaced with a magnification that changes isotropically in both the X-axis and Y-axis directions. In this case, the magnification of the projection optical system 10 can be corrected by driving the optical elements (lenses and mirrors) in the projection optical system 10.

[0087] An article manufacturing method in which an exposure apparatus EX is used to manufacture an article. This article manufacturing method may include a formation step of forming a pattern on a substrate using the exposure apparatus EX, and a processing step of processing the substrate after the formation step to obtain an article. The pattern formed in the formation step is, for example, a latent image formed on a photosensitive material on the substrate. The processing step may include, for example, a development step. The processing step may also include a deposition step, an etching step, a slicing step, a sealing step, etc. In this article manufacturing method, the formation step of forming the pattern on the substrate and the associated processing (e.g., the development step) may be performed multiple times.

[0088] Other embodiments

[0089] One or more embodiments of the present invention can also be implemented by a computer that reads and executes computer-executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be more fully referred to as a "non-transient computer-readable storage medium") to perform the functions of one or more embodiments described above and / or includes one or more circuits (e.g., application-specific integrated circuits (ASICs)) for performing the functions of one or more embodiments described above, and by a method executed by a computer of a system or device, for example, by reading and executing computer-executable instructions from a storage medium to perform the functions of one or more embodiments described above and / or controlling one or more circuits to perform the functions of one or more embodiments described above. The computer may include one or more processors (e.g., a central processing unit (CPU), a microprocessor unit (MPU)) and may include a network of separate computers or separate processors to read and execute the computer-executable instructions. The computer-executable instructions may be provided to the computer, for example, from a network or storage medium. Storage media may include one or more of the following: hard disk, random access memory (RAM), read-only memory (ROM), storage device for distributed computing systems, optical disc (such as compact disc (CD), digital versatile disc (DVD) or Blu-ray disc (BD)™), flash memory device, memory card, etc.

[0090] Other embodiments

[0091] The embodiments of the present invention can also be implemented by the following method: providing software (including computer program products of computer programs) that performs the functions of the above embodiments to a system or device via a network or various storage media, and the computer (central processing unit (CPU) or microprocessor unit (MPU) of the system or device) reads and executes the computer program.

[0092] While this disclosure has been described with reference to embodiments, it is to be understood that this disclosure is not limited to the disclosed embodiments. The scope of the appended claims is to be given the broadest interpretation in order to cover all such modifications as well as equivalent structures and functions.

Claims

1. A method for controlling an exposure apparatus, the exposure apparatus being configured to expose a substrate by projecting a pattern of a master onto the substrate under set illumination conditions using a projection optics system, the control method comprising: The first acquisition step acquires a first light intensity distribution and a second light intensity distribution. The first light intensity distribution is formed on the pupil surface of the projection optical system when the original is arranged on the object surface of the projection optical system and the original is illuminated under the illumination conditions. The second light intensity distribution is formed on the pupil surface when the object surface is not arranged on the object surface and the object surface is illuminated under the illumination conditions. The second acquisition step acquires first change information and second change information. The first change information indicates a first change, which is a change in the optical properties of the projection optical system that affects the imaging of a first pattern extending in a first direction under the illumination conditions. The second change information indicates a second change, which is a change in the optical properties of the projection optical system that affects the imaging of a second pattern extending in a second direction under the illumination conditions. The second direction is different from the first direction. The generation step generates control data by performing a weighted average of the first change and the second change based on the first light intensity distribution and the second light intensity distribution; as well as An exposure step, which performs exposure of multiple substrates based on the control data.

2. The method according to claim 1, wherein, In the second acquisition step, a first prediction model indicating the first change is generated as the first change information, and a second prediction model indicating the second change is generated as the second change information.

3. The method according to claim 2, wherein, Generating the first prediction model includes determining the saturation value of the optical properties of the projection optical system in relation to the first change, and generating the second prediction model includes determining the saturation value of the optical properties of the projection optical system in relation to the second change.

4. The method according to claim 1, wherein, In the second acquisition step, the first change information is generated by measuring the image of the first pattern, and the second change information is generated by measuring the image of the first pattern.

5. The method according to claim 1, wherein, The first change is a change in the optimal focal position of the first pattern, and the second change is a change in the optimal focal position of the second pattern.

6. The method according to claim 5, wherein, The control data includes data used for focus control.

7. The method according to claim 5, wherein, The control data includes data for controlling the position of the substrate in relation to the optical axis direction of the projection optical system to perform focus control.

8. The method according to claim 5, wherein, In the generation step, the control data is generated to reduce the impact of variations in the average value of the optimal focal position of the first pattern and the optimal focal position of the second pattern.

9. The method according to claim 5, wherein, In the exposure step, focus control with accompanying focus measurement is performed on the substrate to be exposed first among the plurality of substrates, and focus control with accompanying focus measurement is not performed on at least one of the remaining substrates.

10. The method according to claim 1, wherein, The first change is a change in the magnification of the projection optical system in relation to the first direction, and the second change is a change in the magnification of the projection optical system in relation to the second direction.

11. The method according to claim 10, wherein, The control data includes data for controlling the magnification of the projection optics system in relation to the first direction and the second direction.

12. The method according to claim 1, wherein, The weighting is performed based on the magnitude ratio of the first light intensity distribution and the second light intensity distribution in relation to the first direction, and the magnitude ratio of the first light intensity distribution and the second light intensity distribution in relation to the second direction.

13. The method according to claim 1, wherein, The first direction and the second direction are orthogonal to each other.

14. A program stored in a medium and configured to cause a computer to perform the control method defined in any one of claims 1 to 13.

15. A computer that includes the program defined in claim 14 and is configured as a control device for controlling an exposure apparatus.

16. An exposure apparatus configured to expose a substrate by projecting a pattern of an original onto the substrate under set illumination conditions using a projection optics system, the exposure apparatus comprising: A measuring device configured to acquire a first light intensity distribution and a second light intensity distribution, the first light intensity distribution being formed on the pupil surface of the projection optical system when the original is disposed on the object surface of the projection optical system and the original is illuminated under the illumination conditions, and the second light intensity distribution being formed on the pupil surface when the object surface is not disposed on the object surface and the object surface is illuminated under the illumination conditions. as well as A controller is configured to acquire first change information and second change information, the first change information indicating a first change, which is a change in the optical properties of the projection optical system affecting the imaging of a first pattern extending in a first direction under the illumination conditions, and the second change information indicating a second change, which is a change in the optical properties of the projection optical system affecting the imaging of a second pattern extending in a second direction different from the first direction under the illumination conditions, and the controller is configured to generate control data by simultaneously performing a weighted average of the first change and the second change based on the first light intensity distribution and the second light intensity distribution. The controller controls the exposure of multiple substrates based on the control data.

17. The apparatus according to claim 16, wherein, The first change is a change in the optimal focal position of the first pattern, and the second change is a change in the optimal focal position of the second pattern.

18. The apparatus according to claim 17, wherein, The control data includes data used for focus control.

19. The apparatus according to claim 17, wherein, The control data includes data for controlling the position of the substrate in relation to the optical axis direction of the projection optical system to perform focus control.

20. The apparatus according to claim 16, wherein, The controller generates the control data to reduce the impact of changes in the average value of the optimal focus position of the first pattern and the optimal focus position of the second pattern.

21. The apparatus according to any one of claims 16 to 20, wherein, The controller performs focus control with accompanying focus measurement on the substrate to be exposed first among the plurality of substrates, and does not perform focus control with accompanying focus measurement on at least one of the remaining substrates.

22. A method for manufacturing an article, comprising: An exposure step, wherein the exposure step is performed by exposing the substrate to the exposure apparatus as defined in any one of claims 16 to 20; as well as The processing step processes the substrate that has undergone the exposure step, thereby obtaining an article.

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