Exposure apparatus, exposure method, and method for manufacturing articles

Abstract

This technology offers advantages in terms of productivity and pattern formation accuracy in exposure equipment. [Solution] An exposure apparatus for performing scanning exposure on a shot area on a substrate comprises a stage for holding the substrate, a measuring unit for measuring the surface height of each of a plurality of measuring areas arranged in the shot area along the scanning direction of the substrate prior to exposure, and a control unit for controlling the drive of the stage. The plurality of measuring areas include a first measuring area and a second measuring area whose surface height is measured by the measuring unit after the first measuring area but before exposure of the first measuring area. The control unit controls the drive of the stage based on the measured surface height values ​​of the first measuring area and the second measuring area obtained by the measuring unit, so that the surface height of the first measuring area is set to a target height when the first measuring area is exposed.

Description

Technical Field

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

Background Art

[0002] In a manufacturing process of a semiconductor device or the like, as a lithography apparatus for forming a pattern on a substrate, an exposure apparatus that performs scanning exposure of the substrate by scanning the substrate with respect to light that has passed through a reticle can be used. In such an exposure apparatus, prior to exposure, while measuring the surface height of the substrate, based on the measurement value, the driving of a stage that holds the substrate is controlled so that the surface height of the substrate is arranged at a target height (for example, the focus position of a projection optical system).

[0003] Patent Document 1 describes a method of measuring the height of a substrate surface at predetermined time intervals and determining a driving command value for the stage based on the measurement value. Specifically, the surface height at position N on the substrate is measured, and based on the measurement value, the driving command value when exposing position N is determined. Similarly, the surface height at position (N + 1) on the substrate is measured, and based on the measurement value, the driving command value when exposing position (N + 1) is determined. Also, the driving command value between position N and position (N + 1) is determined by interpolating the driving command value determined for position N and the driving command value determined for position (N + 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In recent years, with the demand for further productivity improvements in exposure equipment, there has been a need to shorten the time required for scanning exposure by increasing the scanning speed of the substrate. However, increasing the scanning speed of the substrate shortens the measurement time required to measure the surface height of each position (region) on the substrate prior to exposure, which can lead to a decrease in measurement accuracy. In this case, if the drive command value when exposing position N on the substrate is determined based solely on the measured surface height of position N, as in the method described in Patent Document 1, it becomes difficult to accurately position the surface height of position N to the target height. In other words, the pattern formation accuracy may decrease.

[0006] Therefore, the present invention aims to provide a technology that is advantageous in terms of productivity and pattern formation accuracy in exposure equipment. [Means for solving the problem]

[0007] To achieve the above objective, an exposure apparatus as one aspect of the present invention is an exposure apparatus that performs scanning exposure on a shot area on a substrate, comprising: a stage for holding the substrate; a measuring unit for measuring the surface height of each of a plurality of measuring areas arranged in the shot area along the scanning direction of the substrate prior to exposure; and a control unit for controlling the driving of the stage, wherein the plurality of measuring areas include a first measuring area and a second measuring area whose surface height is measured by the measuring unit after the first measuring area before exposure of the first measuring area, and the control unit controls the driving of the stage based on the measured surface height values ​​of the first measuring area and the second measuring area obtained by the measuring unit, so that the surface height of the first measuring area is set to a target height when the first measuring area is exposed.

[0008] Further objects or other aspects of the present invention will be revealed below by preferred embodiments described with reference to the accompanying drawings. [Effects of the Invention]

[0009] According to the present invention, for example, it is possible to provide a technology that is advantageous in terms of productivity and pattern formation accuracy in an exposure apparatus. [Brief explanation of the drawing]

[0010] [Figure 1] Schematic diagram showing an example of the configuration of an exposure apparatus. [Figure 2] A diagram showing the positional relationship between the shot area, the light irradiation area, and multiple measurement points. [Figure 3A] Diagram illustrating scanning exposure for each of multiple shot regions. [Figure 3B] Diagram illustrating scanning exposure for each of multiple shot regions. [Figure 4] This diagram shows the relationship between the scanning speed of the substrate, the measurement time, and the measurement variability. [Figure 5] Diagram showing multiple measurement areas arranged within the shot area. [Figure 6] A diagram illustrating an example of control for driving the substrate stage in the first embodiment. [Figure 7] A diagram illustrating an example of controlling the drive of the substrate stage in Example 1 of the second embodiment. [Figure 8] A diagram illustrating an example of control for driving the substrate stage in Embodiment 2 of the second embodiment. [Figure 9] A diagram illustrating an example of control for driving the substrate stage in Embodiment 3 of the second embodiment. [Figure 10] Diagram showing multiple measurement areas arranged within the shot area. [Figure 11] Flowchart showing the exposure process [Figure 12] Plan view of the substrate showing the area (sample shot area) to be measured for surface height. [Modes for carrying out the invention]

[0011] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiments, not all of these plurality of features are essential to the invention, and the plurality of features may be arbitrarily combined. Further, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant descriptions are omitted.

[0012] In this specification and the accompanying drawings, directions are indicated in an XYZ coordinate system with the image plane (focus plane) of the projection optical system as the XY plane. The directions parallel to the X-axis, Y-axis, and Z-axis in the XYZ coordinate system are referred to as the X-direction, Y-direction, and Z-direction, respectively, and the rotations around the X-axis, Y-axis, and Z-axis are denoted as θX, θY, and θZ, respectively. The control and drive (movement) with respect to the X-axis, Y-axis, and Z-axis respectively mean control or drive (movement) in the direction parallel to the X-axis, Y-axis, and Z-axis. Also, the control or drive with respect to the θX-axis, θY-axis, and θZ-axis respectively mean control or drive related to rotation around an axis parallel to the X-axis, rotation around an axis parallel to the Y-axis, and rotation around an axis parallel to the Z-axis.

[0013] <First Embodiment> The first embodiment according to the present invention will be described. FIG. 1 is a schematic diagram showing a configuration example of an exposure apparatus 100 of the present embodiment. The exposure apparatus 100 performs scanning exposure of the substrate 15 by relatively scanning and driving the reticle 12 and the substrate 15 with respect to exposure light (slit light) having a rectangular or arc-shaped cross-sectional shape, and transfers the pattern of the reticle 12 to the substrate 15. Such an exposure apparatus 100 is also called a step-and-scan type exposure apparatus or a scanner.

[0014] As shown in FIG. 1, the exposure apparatus 100 includes an illumination optical system 11, a reticle stage 13, a projection optical system 14, a substrate stage 16, a measurement unit 17, and a control unit 20. The reticle stage 13 and the substrate stage 16 can constitute a drive mechanism for relatively scanning the reticle 12 and the substrate 15 via the projection optical system 14.

[0015] The illumination optical system 11 illuminates the original plate 12 using light emitted from a light source (not shown) that generates pulsed light such as an excimer laser. The illumination optical system 11 includes, for example, a beam shaping optical system, an optical integrator, a collimator lens, a mirror, etc., efficiently transmits or reflects pulsed light in the far ultraviolet region, and emits it as exposure light (slit light). The beam shaping optical system has a mechanism (e.g., a slit) that shapes the cross-sectional shape (dimensions) of the incident light into a predetermined shape (e.g., rectangular or arc-shaped), and generates exposure light (slit light) using the light from the light source. The exposure light has a cross-sectional shape that defines the illumination region on the original plate 12, i.e., the light irradiation region on the substrate 15. In the case of this embodiment, the beam shaping optical system is configured to generate exposure light having a rectangular cross-sectional shape using the light from the light source. Also, the optical integrator makes the light distribution characteristics of the light uniform and illuminates the original plate 12 with uniform illuminance.

[0016] The projection optical system 14 projects the pattern image of the original plate 12 illuminated by the illumination optical system 11 onto the substrate 15. In FIG. 1, the optical axis AX of the projection optical system 14 extends in the Z direction, and the image plane of the projection optical system 14 is a plane perpendicular to the Z direction (i.e., the XY plane). The exposure light emitted from the illumination optical system 11 irradiates the original plate 12, and a pattern image of the original plate 12 is formed on the image plane of the projection optical system 14 at the projection magnification (e.g., 1 / 4, 1 / 2, 1 / 5) of the projection optical system 14.

[0017] The substrate 15 is, for example, a wafer on which a resist (photosensitive material) is coated. Multiple shot regions having the same pattern structure formed by the lithography process are arranged on the substrate 15. The substrate stage 16 is a stage that holds and moves the substrate 15 and has a chuck for holding (adsorbing, fixing) the substrate 15. The substrate stage 16 is driven by the substrate drive mechanism 24. The substrate stage 16 may also include an XY stage that can move horizontally in the X and Y directions, and a Z stage that can move in the Z direction (height direction of the substrate 15) parallel to the optical axis AX of the projection optical system 14. Furthermore, the substrate stage 16 may also include a leveling stage that can rotate (tilt) in the θX direction around the X axis and the θY direction around the Y axis, and a rotating stage that can rotate in the θZ direction around the Z axis. In this way, the substrate stage 16 can constitute a 6-axis drive system for matching the pattern image of the master plate 12 with the shot regions of the substrate 15. The positions of the substrate stage 16 in the X, Y, and Z directions can be constantly measured by a bar mirror 19 and an interferometer 22 positioned on the substrate stage 16.

[0018] The master plate 12 (mask, reticle) has a pattern to be transferred to each of multiple shot regions on the substrate 15 and is held by the master plate stage 13. The master plate stage 13 is driven by the master plate drive mechanism 23 and scanned in a predetermined direction (e.g., the Y direction) in a plane perpendicular to the optical axis AX of the projection optical system 14. During this scanning, the master plate stage 13 is scanned so that its position in the Y direction always maintains the target position. The positions of the master plate stage 13 in the X and Y directions can always be measured by a bar mirror 18 and an interferometer 21 positioned on the master plate stage 13.

[0019] The measurement unit 17 measures the surface height (surface position) of the substrate 15. In this embodiment, the measurement unit 17 is configured to measure the surface height of the substrate 15 for each of a plurality of measurement areas arranged on the substrate 15 along the scanning direction, prior to exposure (irradiation with exposure light), while the substrate 15 (substrate stage 16) is moving. As shown in Figure 1, the measurement unit 17 in this embodiment is of the oblique incidence type, which irradiates the substrate 15 with light from an oblique angle, and includes an irradiation system that irradiates the substrate 15 with light and a light receiving system that receives the light reflected by the substrate 15. Hereinafter, the measurement of the surface height of the substrate 15 by the measurement unit 17 may be referred to as "focus measurement".

[0020] The irradiation system of the measurement unit 17 may include, for example, a light source 170, a collimator lens 171, a slit member 172, an optical system 173, and a mirror 174. The light source 170 is composed of, for example, a white lamp or a high-brightness light-emitting diode having multiple peak wavelengths that are different from each other, and emits light (measurement light) used to measure the surface height of the substrate 15. The measurement light emitted from the light source 170 should preferably be of a wavelength that does not expose the resist on the substrate 15. The collimator lens 171 converts the light emitted from the light source 170 into a parallel light beam with a nearly uniform light intensity distribution in the cross-section. The slit member 172 is composed of a pair of prisms bonded together so that their bevels face each other, and the bonded surface 172a is provided with a light-shielding film such as chromium in which multiple apertures (for example, 9 pinholes) are formed. The optical system 173 is a double-sided telecentric optical system that directs multiple (e.g., nine) light beams passing through multiple apertures in the slit member 172 (bonding surface 172a) onto the substrate 15 via the mirror 174. The optical system 173 is configured such that the surface where the apertures are formed and the surface including the substrate 15 satisfy the shineproof condition. By directing multiple light beams onto the substrate 15 in this way, focus measurements can be performed individually for each of the multiple measurement areas on the substrate.

[0021] The light-receiving system of the measurement unit 17 may include, for example, a mirror 175, a light-receiving optical system 176, a correction optical system 177, a photoelectric conversion unit 178, and a processing unit 179. The mirror 175 guides multiple light beams reflected by the substrate 15 to the light-receiving optical system 176. The light-receiving optical system 176 is a double-sided telecentric optical system and includes a stopper aperture commonly provided for multiple light beams. The stopper aperture included in the light-receiving optical system 176 blocks higher-order diffracted light (noise light) generated due to the circuit pattern formed on the substrate 15. The correction optical system 177 has multiple (e.g., nine) lenses to correspond to multiple light beams and images the multiple light beams onto the light-receiving surface of the photoelectric conversion unit 178, forming pinhole images on the light-receiving surface for each beam. The photoelectric conversion unit 178 includes multiple (e.g., nine) photoelectric conversion elements to correspond to multiple light beams. As the photoelectric conversion element, a one-dimensional line sensor or a two-dimensional sensor composed of, for example, a CCD sensor or a CMOS sensor may be used. The processing unit 179 calculates the surface height of each measurement area on the substrate 15 based on the position of each pinhole image on the light-receiving surface of the photoelectric conversion unit 178.

[0022] The control unit 20 is composed of a computer including, for example, a processor such as a CPU (Central Processing Unit) and a storage unit such as memory, and controls the scanning exposure of the substrate 15 by comprehensively controlling each part of the exposure apparatus 100. For example, the control unit 20 controls the driving of the master plate stage 13 and the substrate stage 16 by the master plate driving mechanism 23 and the substrate driving mechanism 24, respectively, so that the exposure light that has passed through the master plate 12 is imaged onto the substrate 15 (shot area). The control unit 20 can adjust the relative position of the master plate 12 and the substrate 15 by controlling the relative driving of the master plate stage 13 and the substrate stage 16.

[0023] Furthermore, the control unit 20 scans the master plate stage 13 and the substrate stage 16 in synchronization with the projection optical system 14. This allows the control unit 20 to control scanning exposure (exposure process) in which the substrate 15 is scanned with respect to the exposure light by the substrate stage 16 to expose each shot area of ​​the substrate 15. For example, in scanning exposure of the substrate 15, the control unit 20 drives the master plate stage 13 (master plate 12) to scan in the direction of arrow 13a while driving the substrate stage 16 (substrate 15) to scan in the direction of arrow 16a at a speed ratio corresponding to the projection magnification of the projection optical system 14. The scanning speed of the master plate stage 13 can be determined to be advantageous in terms of productivity (throughput) based on the width of the scanning direction of the masking blade in the illumination optical system 11 and the sensitivity of the resist coated on the surface of the substrate 15 (or the intensity of the exposure light irradiated onto the substrate 15).

[0024] Here, the alignment of the pattern of the master plate 12 in the XY plane can be performed based on the position of the master plate stage 13, the position of the substrate stage 16, and the position of each shot area of ​​the substrate 15 relative to the substrate stage 16. The positions of the master plate stage 13 and the substrate stage 16 are measured by interferometers 21 and 22, respectively, as described above. The position of each shot area of ​​the substrate 15 relative to the substrate stage 16 is obtained by an alignment detection unit (not shown) detecting the position of marks provided on the substrate stage 16 and the position of alignment marks formed on the substrate 15.

[0025] Furthermore, the control unit 20 performs focus leveling control (also called focus leveling drive) of the substrate 15 based on the measurement results of the measurement unit 17. Focus leveling control is the control of at least one of the height (position in the Z direction) and tilt (tilt in the θX and θY directions) of the substrate 15 by the substrate stage 16 so that the surface height of the light-irradiated area of ​​the substrate 15 is positioned at the target height. The target height can be set, for example, to the best focus position of the projection optical system 14 (image plane position of the projection optical system 14). In this embodiment, during scanning exposure of the substrate 15 (each shot area), the control unit 20 has the measurement unit 17 measure the surface height of the substrate 15, and sequentially performs focus leveling control of the substrate 15 based on the measured value of the surface height of the substrate 15 obtained by the measurement unit 17. Below, an example of controlling the height of the substrate 15 as focus leveling control will be described.

[0026] Figure 2 shows the positional relationship between the shot area 15a to be scanned, the light-illuminated area 30 to which exposure light emitted from the projection optical system 14 is irradiated, and the multiple measurement points 31-33 where the measurement unit 17 performs focus measurement (surface height measurement). In this embodiment, the measurement unit 17 is configured to measure the surface height of the shot area 15a at each of the nine measurement points 31-33. In Figure 2, the light-illuminated area 30 is a rectangular area enclosed by a dashed line. Measurement points 31 (31a-31c) are measurement points within the light-illuminated area 30 where the measurement unit 17 performs focus measurement. Measurement points 32 (32a-32c) and 33 (33a-33c) are measurement points where the measurement unit 17 performs focus measurement prior to exposure in the light-illuminated area 30. Measurement points 32 and 33 are located at a distance Lp in the scanning direction (±Y direction) from measurement point 31 within the light-illuminated area 30. In the following, the focus measurement performed at measurement point 32 or measurement point 33 prior to exposure in the light-irradiated area 30 may be referred to as "predictive measurement." In this embodiment, each of the measurement points 31 to 33 includes three measurement points arranged in a direction (X direction) intersecting the scanning direction (Y direction), but is not limited to this, and may include two or four or more measurement points.

[0027] In the measurement unit 17 configured in this way, measurement points 32 to 33 used for look-ahead measurement are switched according to the scanning direction (movement direction) of the substrate 15. For example, when scanning exposure of the shot area 15a is performed while scanning the substrate 15 in direction F, measurement point 32 is used for look-ahead measurement. In this case, the control unit 20 controls the driving of the substrate stage 16 in the height direction (Z direction) based on the measurement value at measurement point 32 so that the substrate surface within the light irradiation area 30 is positioned on the best focus plane (imaging plane, image plane) of the projection optical system 14. On the other hand, when scanning exposure of the shot area 15a is performed while scanning the substrate 15 in direction R, measurement point 33 is used for look-ahead measurement. In this case, the control unit 20 controls the driving of the substrate stage 16 in the height direction based on the measurement value at measurement point 33 so that the substrate surface within the light irradiation area 30 is positioned on the image plane of the projection optical system 14.

[0028] Figures 3A to 3B illustrate scanning exposure for each of the multiple shot regions 15a to 15c on the substrate 15. Shot region 15a is the shot region to be scanned. Shot region 15b is the shot region that has been scanned before shot region 15a. Shot region 15c is the shot region that will be scanned after shot region 15a. Figures 3A to 3B also show the light irradiation region 30 and the measurement points 31 to 32 where the measurement unit 17 performs focus measurement. In Figures 3A to 3B, the movement path P of the light irradiation region 30 and the measurement points 31 to 32 on the substrate 15 is indicated by dashed arrows.

[0029] When scanning exposure is completed for shot area 15b, the control unit 20 decelerates the substrate stage 16 (substrate 15) which is moving in direction R, and steps the substrate stage 16 in the X direction to perform scanning exposure for the next shot area 15a. Figure 3A shows the state after scanning exposure is completed for shot area 15b and before the start of look-ahead measurement of shot area 15a by the measurement point 32 of the measurement unit 17. Within the shot area 15a, a plurality of measurement areas 41 to 43 are arranged (set) along the scanning direction (Y direction) of the substrate 15, where look-ahead measurements are sequentially performed by the measurement point 32 of the measurement unit 17 prior to exposure in the light irradiation area 30. For example, measurement area 41 is located at the end of the shot area 15a where scanning exposure begins, and is the first measurement area among the plurality of measurement areas 41 to 43 where look-ahead measurement is performed by the measurement point 32 of the measurement unit 17. In Figure 3A, for the sake of simplicity, only three measurement areas 41-43 are set in the shot area 15a, but more measurement areas can be set in the shot area 15a.

[0030] Next, the control unit 20 accelerates the substrate stage 16 in direction F to start scanning exposure on the shot area 15a. Figure 3B shows the state in which the measurement point 32 of the measurement unit 17 has started predictive measurement of the shot area 15a, that is, the measurement point 32 of the measurement unit 17 is performing predictive measurement on the measurement area 41 of the shot area 15a. At the measurement point 32 of the measurement unit 17, predictive measurement is performed sequentially on each measurement area 41 to 43 of the shot area 15a. When the light irradiation area 30 reaches the shot area 15a, light irradiation to the light irradiation area 30 (i.e., exposure in the light irradiation area 30) is started. Thereafter, predictive measurement is performed sequentially on each measurement area of ​​the shot area 15a by the measurement point 32 of the measurement unit 17, and based on the measured values, the drive of the substrate stage 16 is controlled so that the surface height within the light irradiation area 30 is set to the target height. As mentioned above, the target height can be the best focus position of the projection optical system 14.

[0031] When the light irradiation area 30 passes through the shot area 15a, light irradiation to the light irradiation area 30 (i.e., exposure in the light irradiation area 30) ends. Once scanning exposure is completed for the shot area 15a, the control unit 20 decelerates the substrate stage 16 (substrate 15), which is moving in direction F, and steps the substrate stage 16 in the X direction to perform scanning exposure on the next shot area 15c. Then, the control unit 20 accelerates the substrate stage 16 in direction R and starts scanning exposure on the shot area 15c.

[0032] Incidentally, in recent years, in response to the demand for further productivity improvements in the exposure apparatus 100, there has been a need to shorten the time required for scanning exposure by increasing the scanning speed of the substrate 15. However, increasing the scanning speed of the substrate 15 shortens the measurement time (hereinafter sometimes simply referred to as measurement time) during which the measurement unit 17 performs look-ahead measurements for each measurement area on the substrate 15, which may reduce the measurement accuracy.

[0033] Figure 4 shows the relationship between the scanning speed of the substrate 15, the measurement time, and the variability of the measured values ​​obtained by the measurement unit 17 (measurement variability). Measurement variability can be understood as the measurement error that occurs in the measured values ​​of the measurement unit 17, or as the measurement reproducibility of the measurement unit 17, and represents the measurement accuracy of the measurement unit 17. In Figure 4, the scanning speed, measurement time, and measurement variability are shown as normalized values ​​with condition A set to 1.0. Compared to condition A, the scanning speed of the substrate 15 is set to 1.2 times in condition B, to 1.5 times in condition C, and to 2.0 times in condition D. As can be seen from Figure 4, increasing the scanning speed of the substrate 15 shortens the measurement time and can also increase the measurement variability (measurement error). For example, under condition D, if the scanning speed of the substrate 15 is 2.0 times that of condition A, the measurement time becomes 0.5 times shorter, and the measurement variability (measurement error) may increase by 1.4 times. In other words, increasing the scanning speed of the substrate 15 may reduce the measurement accuracy of the measurement unit 17. A decrease in measurement accuracy can lead to poor resolution due to defocusing.

[0034] One way to improve the measurement accuracy of the measurement unit 17 is to control the drive of the substrate stage 16 in the height direction (Z direction) based on the measured surface height values ​​of two or more measurement areas arranged along the scanning direction. By controlling the drive of the substrate stage 16 based on the measured surface height values ​​of two or more measurement areas in this way, even if the scanning speed of the substrate 15 increases and the measurement time for each measurement area is shortened, the measurement accuracy can be improved by the averaging effect.

[0035] Therefore, the control unit 20 of this embodiment controls the driving of the substrate stage 16 so that the surface height of the first measurement area is positioned at a target height when the first measurement area is exposed, based on the measured surface height values ​​of the first measurement area and the second measurement area obtained by the measurement unit 17. For example, the control unit 20 sets a target driving position based on the measured surface height values ​​of the first measurement area and the second measurement area obtained by the measurement unit 17, and controls the driving of the substrate stage 16 in the height direction (Z direction) based on this target driving position. Here, the second measurement area is a measurement area in which the measurement unit 17 performs look-ahead measurement after the first measurement area before exposure of the first measurement area. The target driving position is the target position (target height) of the substrate stage 16 for positioning the surface height of the first measurement area at a target height when the first measurement area is exposed.

[0036] The following describes an example of controlling the drive of the substrate stage 16 based solely on the measured surface height of the first measurement area, as in the conventional method, and an example of controlling the drive of the substrate stage 16 based on the measured surface heights of both the first and second measurement areas in this embodiment.

[0037] Figure 5 shows a plurality of measurement regions 41 to 43 arranged in the shot region 15a along the scanning direction of the substrate 15. In this embodiment, measurement region 41 may correspond to the first measurement region, and measurement region 42 may correspond to the second measurement region. Figure 6 shows the trajectory of the surface height of the measurement region 41 to illustrate control examples of the drive of the substrate stage 16 in the conventional and this embodiment. In Figure 6, trajectory 51 shows a conventional control example, and trajectory 52 shows a control example in this embodiment.

[0038] In Figure 6, "Ht" is the target height at which the measurement area 41 should be positioned when it is exposed. "T1" is the time when the look-ahead measurement of the measurement area 41 by the measurement unit 17 (measurement point 32) is completed. "T2" is the time when the look-ahead measurement of the measurement area 42 by the measurement unit 17 (measurement point 32) is completed. "Ts" is the time when the light irradiation area 30 reaches the shot area 15a (measurement area 41). At time Ts, light irradiation to the light irradiation area 30 begins, and exposure of the shot area 15a (measurement area 41) begins. Therefore, it is necessary to control the drive of the substrate stage 16 so that the surface height of the measurement area 41 is positioned at the target height by time Ts.

[0039] First, a conventional control example in which the drive of the substrate stage 16 is controlled based on the measured surface height of one measurement area 41 will be described. The measurement unit 17 starts a look-ahead measurement of the measurement area 41 when the measurement point 32 reaches the measurement area 41, and ends the look-ahead measurement of the measurement area 41 at time T1 when the measurement point 32 leaves the measurement area 41. Once the look-ahead measurement of the measurement area 41 is completed, the measurement unit 17 outputs the average value of the surface height measured across the measurement area 41 as the "measured surface height of the measurement area 41 (hereinafter sometimes referred to as the measured value of the measurement area 41)". Based on the measured value of the measurement area 41 obtained from the measurement unit 17, the control unit 20 sets (determines, calculates) the target drive position of the substrate stage 16 to position the surface height of the measurement area 41 at the target height, and controls the drive of the substrate stage 16 based on that target drive position.

[0040] As mentioned above, increasing the scanning speed of the substrate 15 shortens the measurement time of the measurement area 41, which can lead to significant errors in the measured values ​​of the measurement area 41. If the drive target position of the substrate stage 16 is set based solely on the measured values ​​of the measurement area 41, which include such errors, it may become difficult to position the surface height of the measurement area 41 at the exposure time (time Ts), as shown by the trajectory 51 in Figure 6. In other words, a difference dZ1 may occur between the surface height of the measurement area 41 and the target height at the exposure time (time Ts). Depending on the magnitude of this difference dZ1, resolution problems due to defocus may occur.

[0041] Next, an example of control in this embodiment, which controls the driving of the substrate stage 16 based on the measured surface height values ​​of two measurement areas 41 to 42, will be described. The measurement unit 17 starts predictive measurement of measurement area 41 when the measurement point 32 reaches measurement area 41 (first measurement area), and ends predictive measurement of measurement area 41 at time T1 when the measurement point 32 leaves measurement area 41. When predictive measurement of measurement area 41 is completed, the measurement unit 17 outputs the average value of the surface height measured across measurement area 41 as the "measured value of measurement area 41". The measurement unit 17 also starts predictive measurement of measurement area 42 when the measurement point 32 reaches measurement area 42 (second measurement area), and ends predictive measurement of measurement area 42 at time T2 when the measurement point 32 leaves measurement area 42. When the measurement of the surface height of the measurement area 42 is completed, the measurement unit 17 outputs the average value of the surface height measured across the measurement area 42 as the "measured surface height of the measurement area 42 (hereinafter sometimes referred to as the measured value of the measurement area 42)".

[0042] The control unit 20 sets (determines and calculates) the target drive position of the substrate stage 16 to position the surface height of measurement area 41 at the target height, based on the measured values ​​of measurement areas 41 and 42 obtained from the measurement unit 17. For example, the control unit 20 sets the target drive position of the substrate stage 16 based on the average value of the measured values ​​of measurement area 41 and measurement area 42. Then, the control unit 20 controls the driving of the substrate stage 16 based on that target drive position.

[0043] As described above, in this embodiment, the drive target position of the substrate stage 16 for positioning the surface height of measurement area 41 to the target height is set based on the measured value of measurement area 41 and the measured value of measurement area 42, which is measured in advance after measurement area 41. As a result, due to the averaging effect of the measured values ​​of measurement areas 41 and 42, the surface height of measurement area 41 can be accurately positioned to the target height at the time of exposure of measurement area 41 (time Ts), as shown in the trajectory 52 in Figure 6. In other words, the difference dZ1 between the surface height of measurement area 41 and the target height at the time of exposure of measurement area 41 (time Ts) can be reduced, thereby reducing resolution defects due to defocus.

[0044] <Second Embodiment> A second embodiment of the present invention will now be described. This embodiment basically follows the first embodiment, and can be described in accordance with the first embodiment except for the matters mentioned below.

[0045] In the first embodiment described above, the substrate stage 16 was started to drive based on the measured values ​​of the measurement areas 41 to 42 after the look-ahead measurement of the measurement areas 41 to 42 was completed. However, in this case, since the driving time of the substrate stage 16 is shortened, it may be difficult to position the surface height of the measurement area 41 to the target height by the time Ts when the light irradiation area 30 reaches the measurement area 41.

[0046] For example, as shown by trajectory 51 in Figure 6, if the substrate stage 16 is started to drive at time T1 when the look-ahead measurement of the measurement area 41 is completed, the period during which the substrate stage 16 can be driven until time Ts when the light-irradiated area 30 reaches the measurement area 41 is "t1". On the other hand, as shown by trajectory 52 in Figure 6, if the substrate stage 16 is started to drive at time T2 when the look-ahead measurement of the measurement area 42 is completed, the period during which the substrate stage 16 can be driven until time Ts is "t2", which is shorter than the period t1. In this case, depending on the scanning speed of the substrate 15 and the amount of drive of the substrate stage 16, it may become difficult to position the surface height of the measurement area 41 at the target height during the period t2 from time T2 to time Ts, which may cause resolution problems due to defocusing.

[0047] Therefore, in this embodiment, once a look-ahead measurement is performed on the first measurement area, the control unit 20 determines the drive target position based on the measured surface height of the first measurement area and controls the driving of the substrate stage 16 based on the drive target position. Then, once a look-ahead measurement is performed on the second measurement area, the control unit 20 resets (updates) the drive target position based on the measured surface height of the first measurement area and the measured surface height of the second measurement area, and controls the driving of the substrate stage 16 based on the reset drive target position. As described above, the second measurement area is a measurement area where a look-ahead measurement is performed by the measurement unit 17 after the first measurement area, before exposure of the first measurement area. The drive target position is the target position (target height) of the substrate stage 16 for positioning the surface height of the first measurement area to the target height when the first measurement area is exposed. Hereinafter, embodiments 1 to 3 of this embodiment will be described.

[0048] [Example 1] Example 1 describes an example in which look-ahead measurements of the first and second measurement regions are performed before exposure of the first measurement region. In Example 1, as shown in Figure 5, among the multiple measurement regions 41 to 43 arranged in the shot region 15a, measurement region 41 may correspond to the first measurement region and measurement region 42 may correspond to the second measurement region.

[0049] Figure 7 shows the trajectory of the surface height of the measurement area 41 to illustrate an example of control for driving the substrate stage 16 in Example 1. "Ht", "T1", "T2", and "Ts" in Figure 7 are the same as in Figure 6.

[0050] The measurement unit 17 starts predictive measurement of the measurement area 41 (first measurement area) when the measurement point 32 reaches the measurement area 41, and ends predictive measurement of the measurement area 41 at time T1 when the measurement point 32 leaves the measurement area 41. After the predictive measurement of the measurement area 41 is completed, the measurement unit 17 outputs the average value of the surface height measured across the measurement area 41 as the "measured value of the measurement area 41". Based on the measured value of the measurement area 41 obtained from the measurement unit 17, the control unit 20 sets the drive target position of the substrate stage 16 to position the surface height of the measurement area 41 at the target height, and controls the drive of the substrate stage 16 based on that drive target position. In this case, the trajectory of the surface height of the measurement area 41 (first measurement area) is shown as trajectory 61 in Figure 7.

[0051] Thus, after the look-ahead measurement of measurement area 41 is completed but before the look-ahead measurement of measurement area 42 is completed, the drive target position set based only on the measured value of measurement area 41 is used. With this drive target position, as shown by the trajectory 61 in Figure 7, it may be difficult to position the surface height of measurement area 41 at the exposure time (time Ts) of measurement area 41. In other words, at the exposure time (time Ts) of measurement area 41, a difference dZ1 may occur between the surface height of measurement area 41 and the target height. Depending on the magnitude of this difference dZ1, resolution problems due to defocus may occur. Therefore, in Example 1, once further look-ahead measurements of measurement area 42 are performed, the drive target position is reset (updated) based on both the measured value of measurement area 41 and the measured value of measurement area 42.

[0052] The measurement unit 17 starts predictive measurement of the measurement area 42 (second measurement area) when the measurement point 32 reaches the measurement area 42, and ends predictive measurement of the measurement area 42 at time T2 when the measurement point 32 leaves the measurement area 42. After the predictive measurement of the measurement area 42 is completed, the measurement unit 17 outputs the average value of the surface height measured across the measurement area 42 as the "measured value of measurement area 42". The control unit 20 resets the drive target position based on the measured values ​​of measurement area 41 and measurement area 42 obtained from the measurement unit 17, and controls the driving of the substrate stage 16 based on that drive target position. For example, the control unit 20 resets the drive target position based on the average value of the measured values ​​of measurement areas 41 and 42, and controls the driving of the substrate stage 16 based on that drive target position. In this case, the trajectory of the surface height of measurement area 41 (first measurement area) is shown as trajectory 62 in Figure 7.

[0053] Thus, after the look-ahead measurement of measurement area 42 is completed, the drive target position set based on both the measured values ​​of measurement area 41 and measurement area 42 is used. In other words, the drive target position can be set with high accuracy due to the averaging effect of the measured values ​​of measurement areas 41 and 42. Furthermore, since the substrate stage 16 is driven to some extent before time T2 when the look-ahead measurement of measurement area 42 is completed, it is possible to accurately position the surface height of measurement area 41 to the target height even in the short period t2 from time T2 to time Ts. Therefore, the difference dZ1 between the surface height of measurement area 41 and the target height that may occur during exposure of measurement area 41 (time Ts) can be reduced, thereby reducing resolution defects due to defocus.

[0054] [Example 2] In Example 2, we describe an example in which look-ahead measurements are performed for the first measurement area, the second measurement area, and the third measurement area before exposure of the first measurement area. The third measurement area is a measurement area in which look-ahead measurements are performed by the measurement unit 17 after the second measurement area, before exposure of the first measurement area. In Example 2, as shown in Figure 5, among the multiple measurement areas 41 to 43 arranged in the shot area 15a, measurement area 41 may correspond to the first measurement area, measurement area 42 may correspond to the second measurement area, and measurement area 43 may correspond to the third measurement area.

[0055] Figure 8 shows the trajectory of the surface height of the measurement area 41 to illustrate an example of control for driving the substrate stage 16 in Embodiment 2. In Figure 8, "Ht", "T1", "T2", and "Ts" are the same as in Figure 6. Also, in Figure 8, "T3" is the time when the look-ahead measurement of the measurement area 43 by the measurement unit 17 (measurement point 32) is completed.

[0056] The measurement unit 17 starts predictive measurement of the measurement area 41 (first measurement area) when the measurement point 32 reaches the measurement area 41, and ends predictive measurement of the measurement area 41 at time T1 when the measurement point 32 leaves the measurement area 41. After the predictive measurement of the measurement area 41 is completed, the measurement unit 17 outputs the average value of the surface height measured across the measurement area 41 as the "measured value of the measurement area 41". Based on the measured value of the measurement area 41 obtained from the measurement unit 17, the control unit 20 sets the drive target position of the substrate stage 16 to position the surface height of the measurement area 41 at the target height, and controls the drive of the substrate stage 16 based on that drive target position. In this case, the trajectory of the surface height of the measurement area 41 (first measurement area) is shown as trajectory 71 in Figure 8.

[0057] The measurement unit 17 starts predictive measurement of the measurement area 42 (second measurement area) when the measurement point 32 reaches the measurement area 42, and ends predictive measurement of the measurement area 42 at time T2 when the measurement point 32 leaves the measurement area 42. After the predictive measurement of the measurement area 42 is completed, the measurement unit 17 outputs the average value of the surface height measured across the measurement area 42 as the "measured value of measurement area 42". The control unit 20 resets (updates) the drive target position based on the measured values ​​of measurement area 41 and measurement area 42 obtained from the measurement unit 17, and controls the driving of the substrate stage 16 based on that drive target position. For example, the control unit 20 resets the drive target position based on the average value of the measured values ​​of measurement areas 41 and 42, and controls the driving of the substrate stage 16 based on that drive target position. In this case, the trajectory of the surface height of measurement area 41 (first measurement area) is shown as trajectory 72 in Figure 8.

[0058] The measurement unit 17 starts predictive measurement of the measurement area 43 (third measurement area) when the measurement point 32 reaches the measurement area 43, and ends predictive measurement of the measurement area 43 at time T3 when the measurement point 32 leaves the measurement area 43. After the predictive measurement of the measurement area 43 is completed, the measurement unit 17 outputs the average value of the surface height measured across the measurement area 43 as the "measured value of measurement area 43". The control unit 20 resets (updates) the drive target position based on the measured values ​​of measurement area 41, measurement area 42, and measurement area 43 obtained from the measurement unit 17, and controls the driving of the substrate stage 16 based on that drive target position. For example, the control unit 20 resets the drive target position based on the average value of the measured values ​​of measurement areas 41 to 43, and controls the driving of the substrate stage 16 based on that drive target position. In this case, the trajectory of the surface height of measurement area 41 (first measurement area) is shown as trajectory 73 in Figure 8.

[0059] In this way, the measurement area measured by the measurement unit 17 is increased before exposure of the measurement area 41, and the drive target position is reset each time the look-ahead measurement of each measurement area is completed. This further reduces the difference dZ1 between the surface height of the measurement area 41 and the target height that may occur when the measurement area 41 is exposed (time Ts), thereby reducing resolution defects due to defocus.

[0060] [Example 3] Example 3 describes an example in which look-ahead measurements are performed for the first measurement area, the second measurement area, and the fourth measurement area before exposure of the first measurement area. The fourth measurement area is a measurement area in which look-ahead measurements are performed by the measurement unit 17 between the first measurement area and the second measurement area before exposure of the first measurement area. However, in Example 3, the drive target position is not reset at the end of the look-ahead measurement of the fourth measurement area. Here, in Example 3, as shown in Figure 5, among the multiple measurement areas 41 to 43 arranged in the shot area 15a, measurement area 41 may correspond to the first measurement area, measurement area 42 may correspond to the fourth measurement area, and measurement area 43 may correspond to the second measurement area.

[0061] Figure 9 shows the trajectory of the surface height of the measurement area 41 to illustrate an example of control for driving the substrate stage 16 in Embodiment 3. "Ht", "T1", "T2", and "Ts" in Figure 9 are the same as in Figure 6. Also, "T3" in Figure 9 is the time when the look-ahead measurement of the measurement area 43 by the measurement unit 17 (measurement point 32) is completed.

[0062] The measurement unit 17 starts predictive measurement of the measurement area 41 (first measurement area) when the measurement point 32 reaches the measurement area 41, and ends predictive measurement of the measurement area 41 at time T1 when the measurement point 32 leaves the measurement area 41. Once predictive measurement of the measurement area 41 is complete, the measurement unit 17 outputs the average value of the surface height measured across the measurement area 41 as the "measured value of the measurement area 41". Based on the measured value of the measurement area 41 obtained from the measurement unit 17, the control unit 20 sets the drive target position of the substrate stage 16 to position the surface height of the measurement area 41 at the target height, and controls the drive of the substrate stage 16 based on that drive target position. In this case, the trajectory of the surface height of the measurement area 41 (first measurement area) is shown as trajectory 81 in Figure 9.

[0063] The measurement unit 17 starts predictive measurement of the measurement area 42 (fourth measurement area) when the measurement point 32 reaches the measurement area 42, and ends predictive measurement of the measurement area 42 at time T2 when the measurement point 32 leaves the measurement area 42. Once predictive measurement of the measurement area 42 is complete, the measurement unit 17 outputs the average value of the surface height measured across the measurement area 42 as the "measured value of measurement area 42". The drive target position is not reset when predictive measurement of the measurement area 42 is completed.

[0064] The measurement unit 17 starts predictive measurement of the measurement area 43 (second measurement area) when the measurement point 32 reaches the measurement area 43, and ends predictive measurement of the measurement area 43 at time T3 when the measurement point 32 leaves the measurement area 43. After the predictive measurement of the measurement area 43 is completed, the measurement unit 17 outputs the average value of the surface height measured across the measurement area 43 as the "measured value of measurement area 43". The control unit 20 resets (updates) the drive target position based on the measured values ​​of measurement area 41, measurement area 42, and measurement area 43 obtained from the measurement unit 17, and controls the driving of the substrate stage 16 based on that drive target position. For example, the control unit 20 resets the drive target position based on the average value of the measured values ​​of measurement areas 41 to 43, and controls the driving of the substrate stage 16 based on that drive target position. In this case, the trajectory of the surface height of measurement area 41 (first measurement area) is shown as trajectory 82 in Figure 9.

[0065] Even with this method of setting the drive target position of the substrate stage 16, it is possible to reduce the difference dZ1 between the surface height of the measurement area 41 and the target height that may occur during exposure of the measurement area 41 (time Ts), thereby reducing resolution defects due to defocus.

[0066] <Third Embodiment> A third embodiment of the present invention will now be described. This embodiment basically follows the first embodiment, and can be carried out according to the first embodiment except for matters mentioned below. In addition, the second embodiment (Examples 1 to 3) may be applied to this embodiment.

[0067] Figure 10 shows a plurality of measurement regions 41-42 arranged in the shot region 15a along the scanning direction of the substrate 15. Figure 10 may be understood as an enlarged view of the portion of Figure 5 that includes the measurement regions 41-42, but it is characterized by a larger rate of change in surface height in the measurement regions 41-42 compared to Figure 5. In this embodiment, measurement region 41 may correspond to the first measurement region, and measurement region 42 may correspond to the second measurement region.

[0068] In Figure 10, the average surface height A1 measured across measurement area 41 is shown as the "measured value of measurement area 41," and the average surface height A2 measured across measurement area 42 is shown as the "measured value of measurement area 42." Figure 10 also shows the average value At of the measured values ​​from measurement area 41 to 42. The average value At may be understood as the average surface height measured across measurement area 41 to 42.

[0069] Focusing on measurement region 41, a difference dZ2 is observed between the measured value A1 in measurement region 41 and the average value At of measurement regions 41-42. If this difference dZ2 affects the depth of focus of the projection optical system 14, it may cause defocusing during exposure of measurement region 41.

[0070] One countermeasure when this difference dZ2 affects the depth of focus is to determine whether or not to reset the drive target position of the substrate stage 16 based on the difference between the measured value A1 in measurement area 41 (first measurement area) and the measured value A2 in measurement area 42 (second measurement area). For example, if the difference between the measured value A1 in measurement area 41 and the measured value A2 in measurement area 42 is greater than a threshold, the control unit 20 determines that the difference dZ2 between the measured value A1 and the average value At affects the depth of focus of the projection optical system 14 and does not reset the drive target position of the substrate stage 16.

[0071] Another measure involves resetting the target drive position of the substrate stage 16 based on the weighted results of the measurement value A1 in measurement area 41 (first measurement area) and the measurement value A2 in measurement area 42 (second measurement area). For example, the control unit 20 sets the weight w1 assigned to the measurement value A1 in measurement area 41 and the weight w2 assigned to the measurement value A2 in measurement area 42 so that "w1 > w2", and calculates the average value At using the weighted average method. Then, the control unit 20 resets the target drive position of the substrate stage 16 based on this average value At.

[0072] Furthermore, as shown in Figure 4, consider the case where the relationship between the scanning speed of the substrate 15, the measurement time during which the measurement unit 17 performs look-ahead measurement, and the measurement variability is known in advance. In this case, if the measurement time required for each measurement area is greater than the time threshold, the drive target position of the substrate stage 16 may not be reset. The time threshold can be set, for example, to the time at which the measurement accuracy of the measurement unit 17 satisfies the required accuracy.

[0073] <Fourth Embodiment> A fourth embodiment of the present invention will now be described. In this embodiment, the exposure process (exposure method) performed by the exposure apparatus 100 described above will be explained. Figure 11 is a flowchart of the exposure process of this embodiment. Each step in the flowchart can be controlled by the control unit 20.

[0074] In step S1, the control unit 20 uses a transport hand (not shown) to load the substrate 15 onto the substrate stage 16 and holds it in a chuck (not shown). Next, in step S2, the control unit 20 performs pre-measurement and correction for global alignment, which will be performed in step S6, described later (pre-alignment). Specifically, the control unit 20 uses a low-magnification alignment scope (not shown) to measure and correct the amount of deviation in the position and rotation of the substrate 15 so that the marks on the substrate 15 are within the field of view of a high-magnification alignment scope (not shown) used for global alignment.

[0075] In step S3, the control unit 20 uses the measurement unit 17 to measure the surface height at multiple locations on the substrate 15 and calculates and corrects the overall tilt of the substrate 15 (global tilt). Figure 12 is a plan view of the substrate 15 showing, as an example, the locations (sample shot area 15s) to be measured for surface height. Next, in step S4, the control unit 20 performs pre-adjustments for the look-ahead measurement of scanning exposure in step S7, which will be described later. Pre-adjustments may include, for example, adjusting the light intensity of the measurement light source of the measurement unit 17 and obtaining correction values ​​to correct errors that depend on the pattern structure on the substrate 15.

[0076] In step S5, the control unit 20 calculates correction values ​​for the tilt of the projection lens and field curvature in the projection optical system 14 using an unillustrated light intensity sensor and reference mark on the substrate stage 16 and an unillustrated reference plate on the master plate stage 13. Specifically, the light intensity sensor measures the change in the amount of exposure light when the substrate stage 16 is scanned in the X, Y, and Z directions. The amount of displacement of the reference mark relative to the reference plate is measured from the amount of change in light intensity of the light intensity sensor, and the correction values ​​are calculated and corrected.

[0077] In step S6, the control unit 20 measures alignment marks on the substrate 15 using a high-magnification alignment scope (not shown) and calculates the total displacement of the substrate 15 and the common displacement of each shot area. In order to precisely measure the alignment marks, the contrast of the alignment marks must be at the best contrast position. The best contrast position is measured using the measurement unit 17 and the alignment scope. Specifically, the substrate stage 16 is driven to a predetermined height, and the contrast is measured using the alignment scope while the surface height is measured using the measurement unit 17. This process is repeated several times. At this time, the contrast measurement results and the surface height measurement results are associated and stored in the control unit 20. From the obtained multiple contrast measurement results, the surface height with the highest contrast is determined, and that surface height is set as the best contrast position.

[0078] In step S7, the control unit 20 performs scanning exposure on each measurement area arranged in the shot area 15a of the substrate 15, while the measurement unit 17 performs look-ahead measurements on each measurement area. At this time, the methods described in the first to third embodiments above may be applied. When scanning exposure is completed on all shot areas of the substrate 15, the process proceeds to step S8, where the control unit 20 removes the substrate 15 from the substrate stage 16. This completes the series of exposure processes.

[0079] <Embodiment for manufacturing an article> The article manufacturing method according to an embodiment of the present invention is suitable for manufacturing articles such as microdevices, semiconductor devices, and elements having a microstructure. The article manufacturing method of this embodiment includes an exposure step of performing scanning exposure of a substrate using the above-described exposure apparatus (exposure method), a processing step of processing the substrate after the exposure step, and a manufacturing step of manufacturing an article from the substrate after the processing step. The exposure step may be a step of forming a latent image pattern on a photosensitive agent coated on a substrate using the above-described exposure apparatus (exposure method), in which case the processing step may include a step of developing the substrate on which the latent image pattern has been formed. Furthermore, the article manufacturing method includes other well-known steps (oxidation, film formation, vapor deposition, doping, planarization, etching, resist stripping, dicing, bonding, packaging, etc.). The article manufacturing method of this embodiment is advantageous over conventional methods in at least one of the performance, quality, productivity, and production cost of the article.

[0080] <Other examples> 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.

[0081] <Summary of Embodiments> The disclosures herein include at least the following exposure apparatus, exposure method, and article manufacturing method. (Item 1) An exposure apparatus that performs scanning exposure on a shot area on a substrate, A stage for holding the substrate, A measurement unit measures the surface height of each of the multiple measurement regions arranged in the shot region along the scanning direction of the substrate prior to exposure. The system includes a control unit that controls the driving of the aforementioned stage, The plurality of measurement regions include a first measurement region and a second measurement region in which the surface height is measured by the measurement unit before exposure of the first measurement region and after the first measurement region. An exposure apparatus characterized in that the control unit controls the driving of the stage based on the measured surface height values ​​of the first measurement area and the second measurement area obtained by the measurement unit, so that the surface height of the first measurement area is set to a target height when the first measurement area is exposed. (Item 2) The exposure apparatus according to item 1, characterized in that the control unit sets a target drive position for the stage to position the surface height of the first measurement area to the target height when the first measurement area is exposed, based on the measured values ​​of the surface height of the first measurement area and the second measurement area obtained by the measurement unit, and controls the driving of the stage based on the target drive position. (Item 3) The control unit, Once the surface height of the first measurement area is measured by the measurement unit, the drive target position is set based on the measured value of the surface height of the first measurement area. The exposure apparatus according to item 2, characterized in that, once the surface height of the second measurement area is further measured by the measurement unit, the drive target position is reset based on the measured surface heights of the first measurement area and the second measurement area. (Item 4) The exposure apparatus according to item 3, characterized in that the control unit does not reset the drive target position when the difference between the measured value of the surface height of the first measurement area and the measured value of the surface height of the second measurement area is greater than a threshold. (Item 5) The plurality of measurement regions include a third measurement region in which the surface height is measured by the measurement unit before exposure of the first measurement region and after the second measurement region. The exposure apparatus according to item 3 or 4, characterized in that, once the surface height of the third measurement area is further measured by the measurement unit, the control unit resets the drive target position based on the measured surface heights of the first measurement area, the second measurement area, and the third measurement area. (Item 6) The plurality of measurement regions include a fourth measurement region between the first measurement region and the second measurement region, where the surface height is measured by the measurement unit before exposure of the first measurement region. The exposure apparatus according to item 3 or 4, characterized in that the control unit does not reset the drive target position when the surface height of the fourth measurement area is measured by the measurement unit, and resets the drive target position based on the measured surface heights of the first measurement area, the fourth measurement area, and the second measurement area when the surface height of the second measurement area is measured by the measurement unit. (Item 7) The exposure apparatus according to any one of items 2 to 6, characterized in that the control unit sets the drive target position based on the average value of the measured surface height of the first measurement area and the measured surface height of the second measurement area. (Item 8) The exposure apparatus according to any one of items 2 to 7, characterized in that the control unit sets the drive target position based on the result of weighting the measured surface height of the first measurement area and the measured surface height of the second measurement area, respectively. (Item 9) The exposure apparatus according to any one of items 1 to 8, characterized in that the measurement unit outputs the average value of the surface height measured over the first measurement area as the measured value of the surface height of the first measurement area, and outputs the average value of the surface height measured over the second measurement area as the measured value of the surface height of the second measurement area. (Item 10) The system further comprises a projection optical system for projecting the pattern image of the original plate onto the substrate, The exposure apparatus according to any one of items 1 to 9, characterized in that the target height is the best focus position of the projection optical system. (Item 11) The exposure apparatus according to any one of items 1 to 10, characterized in that the first measurement area is located at the end of the shot area where the scanning exposure is to be started. (Item 12) An exposure step in which scanning exposure of a substrate is performed using an exposure apparatus described in any one of items 1 to 11, A processing step for processing the substrate after the exposure step, A manufacturing process for producing an article from the substrate that has undergone the processing step, A method for manufacturing articles, characterized by including the following: (Item 13) An exposure method for performing scanning exposure on a shot area on a substrate, A measurement step of measuring the surface height prior to exposure for each of the plurality of measurement regions arranged in the shot region along the scanning direction of the substrate, The process includes a control step for controlling the drive of a stage that holds the substrate, The plurality of measurement regions include a first measurement region and a second measurement region in which the surface height is measured after the first measurement region before exposure to the first measurement region. The exposure method is characterized in that, in the control step, the drive of the stage is controlled based on the measured values ​​of the surface heights of the first measurement area and the second measurement area obtained in the measurement step, so that when the first measurement area is exposed, the surface height of the first measurement area is set to a target height.

[0082] The invention is not limited to the embodiments described above, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, claims are attached to disclose the scope of the invention. [Explanation of Symbols]

[0083] 11: Illumination optical system, 12: Master plate, 13: Master plate stage, 14: Projection optical system, 15: Substrate, 16: Substrate stage, 17: Measurement unit, 20: Control unit, 100: Exposure device

Claims

1. An exposure apparatus that performs scanning exposure on a shot area on a substrate, A stage for holding the substrate, A measurement unit measures the surface height of each of the multiple measurement regions arranged in the shot region along the scanning direction of the substrate prior to exposure. The system includes a control unit that controls the driving of the aforementioned stage, The plurality of measurement regions include a first measurement region and a second measurement region in which the surface height is measured by the measurement unit before exposure of the first measurement region and after the first measurement region. An exposure apparatus characterized in that the control unit controls the driving of the stage based on the measured surface height values ​​of the first measurement area and the second measurement area obtained by the measurement unit, so that the surface height of the first measurement area is set to a target height when the first measurement area is exposed.

2. The exposure apparatus according to claim 1, wherein the control unit sets a target drive position for the stage to position the surface height of the first measurement area to the target height when the first measurement area is exposed, based on the measured values ​​of the surface height of the first measurement area and the second measurement area obtained by the measurement unit, and controls the driving of the stage based on the target drive position.

3. The control unit, Once the surface height of the first measurement area is measured by the measurement unit, the drive target position is set based on the measured value of the surface height of the first measurement area. The exposure apparatus according to claim 2, characterized in that, once the surface height of the second measurement area is further measured by the measurement unit, the drive target position is reset based on the measured values ​​of the surface heights of the first measurement area and the second measurement area.

4. The exposure apparatus according to claim 3, characterized in that the control unit does not reset the drive target position if the difference between the measured value of the surface height of the first measurement area and the measured value of the surface height of the second measurement area is greater than a threshold.

5. The plurality of measurement regions include a third measurement region in which the surface height is measured by the measurement unit before exposure of the first measurement region and after the second measurement region. The exposure apparatus according to claim 3, wherein the control unit readjusts the drive target position based on the measured surface heights of the first measurement area, the second measurement area, and the third measurement area once the surface height of the third measurement area has been further measured by the measurement unit.

6. The plurality of measurement regions include a fourth measurement region between the first measurement region and the second measurement region, where the surface height is measured by the measurement unit before exposure of the first measurement region. The exposure apparatus according to claim 3, wherein the control unit does not reset the drive target position when the surface height of the fourth measurement area is measured by the measurement unit, and resets the drive target position based on the measured surface heights of the first measurement area, the fourth measurement area, and the second measurement area when the surface height of the second measurement area is measured by the measurement unit.

7. The exposure apparatus according to claim 2, characterized in that the control unit sets the drive target position based on the average value of the measured surface height of the first measurement area and the measured surface height of the second measurement area.

8. The exposure apparatus according to claim 2, characterized in that the control unit sets the drive target position based on the result of weighting the measured surface height of the first measurement area and the measured surface height of the second measurement area, respectively.

9. The exposure apparatus according to claim 1, characterized in that the measurement unit outputs the average value of the surface height measured over the first measurement area as the measured value of the surface height of the first measurement area, and outputs the average value of the surface height measured over the second measurement area as the measured value of the surface height of the second measurement area.

10. The system further comprises a projection optical system for projecting the pattern image of the original plate onto the substrate, The exposure apparatus according to claim 1, characterized in that the target height is the best focus position of the projection optical system.

11. The exposure apparatus according to claim 1, characterized in that the first measurement area is located at the end of the shot area where the scanning exposure is to be started.

12. An exposure step of performing scanning exposure of a substrate using an exposure apparatus according to any one of claims 1 to 11, A processing step for processing the substrate after the exposure step, A manufacturing process for producing an article from the substrate that has undergone the processing step, A method for manufacturing articles, characterized by including the following:

13. An exposure method for performing scanning exposure on a shot area on a substrate, A measurement step of measuring the surface height prior to exposure for each of the plurality of measurement regions arranged in the shot region along the scanning direction of the substrate, The process includes a control step for controlling the drive of a stage that holds the substrate, The plurality of measurement regions include a first measurement region and a second measurement region in which the surface height is measured after the first measurement region before exposure of the first measurement region. The exposure method is characterized in that, in the control step, the drive of the stage is controlled based on the measured surface heights of the first measurement area and the second measurement area obtained in the measurement step, so that when the first measurement area is exposed, the surface height of the first measurement area is set to a target height.

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