Measurement device, exposure apparatus, and object manufacturing method

Abstract

The present disclosure relates to a measurement device, an exposure apparatus, and an object manufacturing method. A measurement device for measuring a height position of an object is provided. The device includes a light projector that projects measurement light onto the object, a light receiver that receives the measurement light reflected by the object, and a processor that determines the height position of the object based on an image of the measurement light received by the light receiver. The light projector projects a coarse detection pattern and a fine detection pattern having a periodic pattern onto the object, and the processor determines a coarse detection value of the height position of the object based on the coarse detection pattern received by the light receiver, and determines a fine detection value of the height position of the object based on the coarse detection value and the fine detection pattern received by the light receiver.

Description

Technical Field

[0001] The present invention relates to a measuring device, an exposure device and an article manufacturing method. Background Art

[0002] Microdevices such as semiconductor devices and liquid crystal display devices are manufactured using photolithography, in which a pattern formed on an original is transferred to a substrate. The exposure device used in the photolithography process has an original stage for supporting the original and a substrate stage for supporting the substrate. The original pattern is transferred to the substrate via a projection optical system while the original stage and the substrate stage are sequentially moved. In the exposure device, each time a corresponding exposure target area (shot region) on the substrate is moved by the substrate stage to an exposure position below the projection optical system, the deviation between the focal point of the projection optical system and the plane position (height position) of the substrate is detected by a measuring device, and the plane position of the substrate is corrected and focused.

[0003] Japanese Patent No. 6491833 discloses measuring the height of a substrate as a target object by using a measuring slit whose length, spacing, and width are caused to change in a stepwise manner. Japanese Patent Laid-Open No. 2018-179665 discloses obtaining the phase of a fringe pattern using a fixed pattern by simultaneously projecting a fringe pattern and a fixed pattern. Japanese Patent No. 5443303 describes performing a small amount of high-precision height measurement by pre-measuring the phase relationship between a long-period pattern and a short-period pattern.

[0004] However, because the pattern in the detection target area is changed according to the technology of Japanese Patent No. 6491833, it may be disadvantageous in terms of measurement accuracy. According to the technology of Japanese Patent Laid-Open No. 2018-179665, since the projection position of the fringe pattern needs to match the projection position of the fixed pattern, the measurement point density may be reduced in proportion to the fixed pattern. In addition, according to the technology of Japanese Patent No. 5443303, since the step of projecting while changing the phase of the periodic pattern needs to be performed at least four times, this may be disadvantageous in terms of measurement time, that is, throughput. Summary of the Invention

[0005] The present invention provides, for example, a measurement apparatus that facilitates both high-precision measurement and high throughput.

[0006] In its first aspect, the present invention provides a measuring device for measuring the height position of an object, the device comprising a light projector configured to project measuring light onto the object, a light receiver configured to receive the measuring light reflected by the object, and a processor configured to determine the height position of the object based on an image of the measuring light received by the light receiver, wherein the light projector is configured to project a coarse detection pattern and a fine detection pattern having a periodic pattern onto the object, and the processor is configured to determine a coarse detection value of the height position of the object based on the coarse detection pattern received by the light receiver, and to determine a fine detection value of the height position of the object based on the coarse detection value and the fine detection pattern received by the light receiver.

[0007] In its second aspect, the present invention provides an exposure device for projecting a pattern of an original onto a substrate through a projection optical system and exposing the substrate, the device comprising a measuring device arranged to measure the height position of the substrate according to the first aspect and a controller, the controller being configured to control the position of the substrate based on the result measured by the measuring device so that the deviation of the height position from the image plane of the projection optical system is reduced.

[0008] The present invention, in its third aspect, provides a method for manufacturing an article, the method comprising exposing a substrate using the exposure apparatus according to the second aspect, and developing the exposed substrate, wherein the article is manufactured from the developed substrate.

[0009] Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the attached drawings). BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a diagram illustrating the configuration of an exposure device.

[0011] Figure 2 A diagram illustrating a shot layout and alignment marks of a substrate.

[0012] Figure 3A and Figure 3B is a diagram illustrating a configuration example of a measurement device and a configuration example of a mask.

[0013] Figures 4A-4D is a diagram for explaining pitch deviation in conventional technology.

[0014] Figure 5 is a diagram illustrating an example of a light projection pattern on a target object.

[0015] Figure 6 is a diagram illustrating an example of a light projection pattern on a target object.

[0016] Figure 7is a diagram illustrating a method for calculating a height position by a measurement device.

[0017] Figure 8 is a diagram illustrating an example of a light projection pattern on a target object.

[0018] Figure 9 is a diagram illustrating an example of a light projection pattern on a target object.

[0019] Figure 10 is a diagram illustrating a method for calculating a height position by a measurement device.

[0020] Figure 11 is a flowchart for describing an exposure method. DETAILED DESCRIPTION

[0021] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments are not intended to limit the scope of the claimed invention. A plurality of features described in the embodiments are not intended to limit the invention to all of the features, and a plurality of such features can be appropriately combined. Furthermore, in the drawings, the same reference numerals are assigned to the same or similar configurations, and redundant descriptions thereof are omitted.

[0022] <First Embodiment>

[0023] Figure 1 is a diagram illustrating a configuration of an exposure device 100 of a measurement device to which the present invention is applied according to an embodiment. Figure 2 is a diagram illustrating a shot layout and an alignment mark of a substrate 3. In the present specification and drawings, directions are shown in an XYZ coordinate system in which a horizontal plane is an XY plane. In general, the substrate 3 is placed on a substrate table 4 so that a surface of the substrate 3 is parallel to the horizontal plane (the XY plane). Therefore, in the following description, directions orthogonal to each other in a plane along the surface of the substrate 3 will be defined as an X axis and a Y axis, and a direction perpendicular to the X axis and the Y axis will be defined as a Z axis. In the following description, directions parallel to the X axis, the Y axis, and the Z axis in the XYZ coordinate system are referred to as an X direction, a Y direction, and a Z direction, and rotational directions around the X axis, the Y axis, and the Z axis are referred to as a θx direction, a θy direction, and a θz direction, respectively.

[0024] In Figure 1In the example, the exposure device 100 includes an original stage 2 that holds an original 1, a movable substrate stage 4 that holds a substrate 3, and an illumination optical system 5 that irradiates the original 1 held on the original stage 2 with exposure light. The exposure device 100 also includes a projection optical system 6 that projects a pattern on the original 1, illuminated by the exposure light, onto the substrate 3 held by the substrate stage 4, thereby exposing the pattern; and a controller 20 that collectively controls the operation of the entire exposure device. The controller 20 may include, for example, a CPU 21 and a memory 22. The memory 22 stores various control data, a control program for the exposure device to be executed by the CPU 21, and the like.

[0025] The exposure device 100 may be, for example, a scanning exposure device (scanner) that exposes the substrate 3 while moving the original 1 and the substrate 3 in synchronization with each other along a scanning direction (e.g., the Y direction). Alternatively, the exposure device 100 may be an exposure device (stepper) of a type in which the substrate 3 is exposed while the original 1 is fixed and the substrate 3 is moved stepwise to expose the next shot area.

[0026] A predetermined illumination area in the original 1 is illuminated with exposure light having a uniform illuminance distribution by the illumination optical system 5. The light source in the illumination optical system 5 may be a mercury lamp, a KrF excimer laser, an ArF excimer laser, an F2 laser, or the like. Alternatively, in order to manufacture smaller semiconductor elements, etc., the illumination optical system 5 may emit extreme ultraviolet light (EUV light) having a wavelength of several to hundreds of nanometers.

[0027] The original stage 2 is movable in the XY plane and can rotate slightly in the θz direction. The original stage 2 is driven by an original stage drive device (not shown) such as a linear motor, and the original stage drive device is controlled by the controller 20. A mirror 7 is provided on the original stage 2. In addition, an XY plane laser interferometer 9 for measuring the position of the mirror 7 is provided at a position facing the mirror 7. The laser interferometer 9 measures the two-dimensional position and rotation angle of the original 1 on the original stage 2 in real time and outputs the measurement results to the controller 20. The controller 20 controls the original stage drive device based on the measurement results of the laser interferometer 9 and performs positioning of the original stage 2 (i.e., the original 1).

[0028] The projection optical system 6 projects the pattern of the original 1 onto the substrate 3 at a predetermined projection magnification and may include a plurality of optical elements. The projection optical system 6 may be a reduction projection system having a projection magnification of, for example, 1 / 4 or 1 / 5.

[0029] The substrate stage 4 includes a θztilt stage for holding the substrate 3 via a substrate chuck (not shown), an XY stage (not shown) for supporting the θztilt stage, and a base (not shown) for supporting the XY stage. The substrate stage 4 is driven by a substrate stage driving device (not shown) such as a linear motor. The substrate stage driving device is controlled by the controller 20. In addition, a mirror 8 that moves together with the substrate stage 4 is provided on the substrate stage 4. Furthermore, a laser interferometer 10 for X and Y axis measurement at a position facing the mirror 8 is provided, and a laser interferometer 12 for Z direction measurement is provided. The X axis position and the Y axis position of the substrate stage 4 and θzare measured in real time by the laser interferometer 10, and the measurement results are output to the controller 20. Furthermore, the Z axis position, θx, and θyof the substrate stage 4 are measured in real time by the laser interferometer 12, and the measurement results are output to the controller 20. The controller 20 controls the substrate stage driving device based on the measurement results of the laser interferometers 10 and 12, and performs positioning of the substrate stage 4 (i.e., the substrate 3).

[0030] A component alignment detection system 13 is provided near the component stage 2. The component alignment detection system 13 detects a component reference mark (not shown) of the component 1 and a substrate side reference mark 17 (see Figure 2 ) on the stage reference plate 11 on the substrate stage 4. Furthermore, the component alignment detection system 13 is equipped with a photoelectric conversion element such as a CCD camera, for example, to detect reflected light from the component reference mark and the substrate side reference mark 17. Based on the signal of the photoelectric conversion element, alignment between the component and the substrate is performed. At this time, by adjusting the position and focus of the component reference mark and the substrate side reference mark 17, the relative positional relationship (X, Y, Z) between the component and the substrate can be adjusted. Incidentally, the substrate side reference mark 17 can be transmissive or reflective. The stage reference plate 11 at the corner of the substrate stage 4 is installed at approximately the same height as the surface of the substrate 3.

[0031] An off-axis (OA) detection system 16 includes an irradiator for irradiating measurement light to a substrate alignment mark 19 (see Figure 2 ) on the substrate 3 and an OA detection system reference mark 18 (see Figure 2 ) on the stage reference plate 11. The OA detection system 16 also includes, inside, a light receiver for receiving reflected light from these marks, a position detector of the substrate alignment mark 19 and the OA detection system reference mark 18.

[0032] A measurement device 15 as a focus / tilt detection system measures the surface position (height position) of the substrate 3 in the height direction (Z axis) by projecting measurement light onto the surface of the substrate 3 as a target object (object) and receiving the measurement light reflected by the substrate 3. Here, the measurement device 15 is configured to be controlled by the controller 20, but the measurement device 15 can be provided with a dedicated controller.

[0033] refer to Figure 3A , the measuring device 15 will be described in detail. The measuring device 15 may include a light projector 110 that projects measurement light onto the substrate 3 and a light receiver 120 that receives the measurement light reflected by the substrate 3. A signal of an image of the measurement light received by the light receiver 120 is transmitted to the controller 20 as a processor, and the controller 20 performs a process of determining the height position of the substrate 3 based on the received signal.

[0034] The light projector 110 may include a condenser lens 111, a mask 112, a lens 113, and a mirror 114. The light receiver 120 may include a mirror 124, a lens 122, and an image capture unit 123. The image capture unit 123 may include an image capture element 121, such as a CCD or CMOS. Light reflected from the light source 115 is condensed by the condenser lens 111 to illuminate the mask 112. A plurality of slits forming a pattern are formed in the mask 112, and measurement light is formed by the mask 112 from the light from the light source 115. The light passing through the plurality of slits in the mask 112 is incident on the substrate 3 at a predetermined angle of incidence via the lens 113 and the mirror 114. The mask 112 and the substrate 3 are in an imaging relationship with respect to the lens 113, and an aerial image of the plurality of slits in the mask 112 is formed on the substrate 3. The lens 113 can be used to place the mask 112 and the substrate 3 in a shine-proof optical relationship. Therefore, by focusing the entire surface of the mask 112 on the substrate 3, measurement accuracy can be improved. When measuring the height of the substrate 3, the measurement value can also be prevented from changing due to local tilt of the substrate 3. The measurement light reflected by the substrate 3 is re-imaged onto the image capture element 121 of the image capture unit 123 via the mirror 124 and the lens 122, and a signal 125 of the slit image corresponding to the multiple slits of the mask 112 is obtained. The lens 122 can be used to place the substrate 3 and the image capture element 121 in a shine-proof optical relationship. Therefore, by focusing the entire surface of the substrate 3 on the image capture element 121, measurement accuracy can be improved. When measuring the height of the substrate 3, the measurement value can also be prevented from changing due to local tilt of the substrate 3. The signal 125 is transmitted to the controller 20, which serves as a processor. The controller 20 obtains the position (height position) of the substrate 3 in the Z direction by detecting the position deviation of the signal 125 received on the image capture element 121.

[0035] The image of the plurality of slits of the mask 112 is projected onto the substrate 3 by the light projector 110. Hereinafter, this is referred to as a "light projection pattern". Figures 4A-4D, the conventional light projection pattern 140 on the substrate 3 will be described. The measuring device accurately determines the height position based on the light projection pattern projected onto the predetermined fine detection area 301 in the field of view 303 of the image capturing element. In the measuring device, in order to measure the height in the fine detection area 301 of the surface of the substrate 3 in detail, it is necessary to make the pattern interval 141 ( Figure 4A ) is as narrow as possible. When the light receiver 120 receives the light projection pattern 140, the pattern image 151 appears on the imaging surface of the image capturing element 121 ( Figure 4B When height measurement is performed using each peak position of the signal of the pattern image 151, the number of measurement points increases in proportion to the increase in the number of peak positions 153 in the field of view 303 of the image capturing element. In order to increase the number of measurement points in the fine detection area 301, it is necessary to make the pattern interval 141 narrower.

[0036] However, when the pattern interval of the light projection pattern 140 is made narrower, the problem of "pitch deviation" may become significant. Figure 4C As shown in FIG, due to the height variation of the substrate 3, there is a light projection pattern 140 in the fine detection area 301 relative to the Figure 4A The pattern deviates from one period. Figure 4D The pattern image 151 received by the light receiver 120 at this time is shown in FIG. Figure 4B Therefore, even if the height of the substrate 3 changes, the detection value of the height in the fine detection area 301 calculated by the controller 20 may not change. Therefore, when the projection position of the light projection pattern having a periodic structure has an error of more than one period, it is impossible to accurately perform height measurement.

[0037] As a countermeasure for such pitch deviation, in this embodiment, the light projector 110 projects different types of light projection patterns onto the substrate 3. The plan view of the mask 112 is shown in FIG. Figure 3B As shown in . The mask 112 has a first region R1 and a second region R2. For example, the first region R1 is a region in the center of the mask 112, and the second region R2 may be a region adjacent to the first region R1 or a region around the first region R1. In the first region R1, a plurality of slits S1 are periodically arranged at intervals D1. When light from the light source 115 passes through the plurality of slits S1, a fine detection pattern having a periodicity is projected onto the substrate 3. In the second region R2, one or more slits are formed. Figure 3B In the example of FIG. 1 , in the second region R2 , the plurality of slits S2 are periodically arranged at an interval D2 greater than the interval D1 . Light from the light source 115 passes through the plurality of slits S2 , whereby the roughness detection pattern is projected onto the substrate 3 .

[0038] The controller 20, which serves as a processor, determines the height position of the substrate 3 based on the roughness detection pattern and the fineness detection pattern received by the light receiver 123. For example, the controller 20 obtains a roughness detection value of the height position of the substrate 3 based on the roughness detection pattern received by the light receiver 123. Thereafter, the controller 20 determines a fineness detection value of the height position of the substrate 3 based on the obtained roughness detection value and the fineness detection pattern received by the light receiver 123.

[0039] Figure 5 An example of a light projection pattern projected on the substrate 3 in this embodiment is shown. Figure 5 In FIG. 2 , the light projection pattern 212 is composed of a fine detection pattern 210 and a rough detection pattern 220. The light projector 110 uses a light source having a structure such as Figure 3B , both the fine detection pattern 210 and the rough detection pattern 220 are projected using the mask 112 having the configuration shown in FIG. The light projector 110 may project the fine detection pattern 210 and the rough detection pattern 220 simultaneously, or may project the fine detection pattern 210 and the rough detection pattern 220 so that the period during which the rough detection pattern 220 is projected overlaps at least a portion of the period during which the fine detection pattern 210 is projected. The fine detection pattern 210 is projected onto the fine detection area 301, and the rough detection pattern 220 is projected onto the rough detection area 302 adjacent to the fine detection area 301. Both the fine detection pattern 210 and the rough detection pattern 220 are incident on the field of view 303 of the image capture element 121. The fine detection pattern 210 and the rough detection pattern 220 may be incident on the field of view 303 of the image capture element 121 simultaneously, and at least a portion of the period during which the rough detection pattern 210 is incident may overlap with the period during which the fine detection pattern 220 is incident. Incidentally, the light projection pattern 212 changes in the direction in which the pattern is projected from the light projector 110 onto the substrate 3 (the Y direction in a plan view viewed from above in the Z direction) depending on the height of the substrate 3, but the entire changed light projection pattern 212 does not need to be suitable for the field of view 303 of the image capturing element 121. It is sufficient that the controller 20 can receive sufficient pattern light so that calculation of the height position can be performed in each of the fine detection pattern 210 and the rough detection pattern 220.

[0040] The fine detection pattern 210 and the roughness detection pattern 220 are formed with different patterns. Furthermore, to increase the number of measurement points in the fine detection area 301, for example, the interval 211 of the fine detection pattern 210 is made smaller than the interval 221 of the roughness detection pattern 220. The interval 221 of the roughness detection pattern 220 is set to a length such that the roughness detection pattern 220 does not vary by a single period within the range of height variation of the substrate 3 (predetermined as the measurement range of the measurement device 100). Therefore, since the roughness detection pattern 220 does not cause pitch deviation (periodic error), the roughness detection value is uniquely determined.

[0041] The roughness detection pattern 220 may be a single pattern without periodicity as long as height calculation can always be performed in the controller 20 with respect to changes in the light projection pattern 112 due to changes in the height of the substrate 3 within the measurement range of the measuring device 100. As an example, the roughness detection pattern 220 may be as follows: Figure 6 Considering the reflectivity of the substrate 3 and the change in the position of the field of view 303 of the image capturing element 121 in the substrate 3, as well as the vignetting caused by the internal structure, etc., the dot pattern can be arranged at multiple positions as the roughness detection pattern 220, such as Figure 6 As shown in .

[0042] For example, the fine detection pattern 210 and the rough detection pattern 220 are adjacent to each other. Because the fine detection pattern 210 and the rough detection pattern 220 are adjacent to each other, the difference in measurement position between the height measurement of the substrate 3 using the fine detection pattern 210 and the height measurement of the substrate 3 using the rough detection pattern 220 can be reduced.

[0043] refer to Figure 7 Next, a description will be given of the height position calculation method performed by the controller 20. The controller 20 obtains a roughness detection value 233 for the height position of the substrate 3 using the roughness detection pattern 220 in the roughness detection area 302. As described above, since the roughness detection pattern 220 is formed to have a pattern that does not cause pitch deviation (periodic error), the roughness detection value 233 is uniquely determined. Thereafter, the controller 20 obtains a fine detection value for the height position of the substrate 3 based on the roughness detection value 233 and the fine detection pattern 210. Specifically, the fine detection value is obtained as follows.

[0044] The controller 20 determines a plurality of height position candidates 231 of the substrate 3 in the measurement range using the fine detection pattern 210 in the fine detection region 301. The plurality of height position candidates 231 can include a height position detected without pitch deviation and a height position detected with pitch deviation of one cycle or more. Since the rough detection pattern measurement position (rough detection region 302) and the measurement position of the fine detection pattern (fine detection region 301) are adjacent, the rough detection value 233 is a value close to the actual height position 230 of the substrate 3 in the fine detection region 301. Therefore, the controller 20 obtains the fine detection value of the plurality of height position candidates 231 having the smallest difference 234 (closest to the rough detection value 233) from the rough detection value 233 as the fine detection value.

[0045] Therefore, it is possible to prevent erroneous detection due to pitch deviation and achieve high-precision height position detection. This measurement technique is also advantageous in terms of throughput because it is not necessary to perform multiple projections for determining the height position as in the conventional technique.

[0046] <Second Embodiment>

[0047] Figure 8 An example of the light projection pattern on the target object in the second embodiment is illustrated. When the height of the substrate 3 as the target object varies, the position at which the light projection pattern 112 is projected on the substrate 3 changes. At this time, if the light projection pattern 112 deviates from the fine detection region 301, it is not possible to perform measurement. Therefore, in the present embodiment, the fine detection pattern 210 is projected onto a region of the surface of the substrate 3 including the fine detection region 301 that is larger than the fine detection region 301, so that it is possible to surely observe the fine detection pattern 210 in the fine detection region 301 even if the height of the object varies.

[0048] In one example, in a plan view of the fine detection region 301 observed from above in the Z direction, the optical axis direction of the measurement light between the light projector 110 and the light receiver 120 is parallel to the Y direction. In this case, when the height of the fine detection region 301 fluctuates, the position at which the fine detection pattern 210 is projected on the fine detection region 301 changes in the Y direction. Therefore, in order to always project the fine detection pattern 210 on the fine detection region 301, the projection range of the fine detection pattern 210 in the Y direction is made larger than the range of the fine detection region 301 in the Y direction.

[0049] In this case, for example, as Figure 8As shown in , the rough detection pattern 220 is set at a position separated in the X direction, with the fine detection pattern 210 interposed therebetween. In order to measure the height of an object using the rough detection pattern 220, the image capture element 121 must always receive the rough detection pattern 220 regardless of how the height of the fine detection area 301 changes. If the height of the object changes, the light projection pattern 112 changes in the Y direction, which is the optical axis direction of the measuring light in the plan view. Therefore, by arranging the rough detection pattern 220 along the X direction perpendicular to the Y direction (the direction in which the pattern changes due to changes in the height of the object), the required size of the image capture element 121 can be reduced. In general, since the size of an image capture element is directly proportional to the price, it is desirable that the size of the image capture element is smaller. In addition, since the transmission speed and the calculation processing speed increase when the number of pixels of the image capture element increases, and a larger image capture element is disadvantageous in terms of measurement throughput, a smaller image capture element is desirable.

[0050] <Third embodiment>

[0051] Figure 9 An example of a coarse detection pattern 92 projected onto a fine detection area 301 and a fine detection pattern 91 projected onto a coarse detection area 302 near the fine detection area 301 is illustrated. The fine detection pattern 91 is a pattern having a first period, and the coarse detection pattern 92 is a pattern having a second period longer than the first period. Figure 5 Compared to the example, Figure 9 The period ratio of the roughness detection pattern 92 in Figure 5 The period of the roughness detection pattern 220 is short. Since the number of measurement points can be increased, the shorter the periodic pattern of the roughness detection pattern 92, the higher the accuracy of height measurement can be. By improving the accuracy of the height measurement of the roughness detection area 302 determined using the roughness detection pattern 92, the height position of the fine detection area 301 can be more accurately determined from the multiple height position candidates 231 selected using the fine detection pattern 91.

[0052] However, although Figure 5 The period of the roughness detection pattern 220 in the example is set to a length that does not cause pitch deviation, but Figure 9 The period of the rough detection pattern 92 is shorter than that of the fine detection pattern 91, and there is a possibility of pitch deviation as with the fine detection pattern 91. Therefore, in this embodiment, the height position is obtained as follows.

[0053] refer to Figure 10The method of calculating the height position in the present embodiment will be described. The controller 20 obtains a roughness detection value of the height position of the substrate 3 using the roughness detection pattern 92 in the roughness detection region 302. However, in the present embodiment, since the roughness detection pattern 92 can cause pitch deviation, the height position is not uniquely determined. Therefore, the controller 20 obtains a plurality of roughness detection value candidates 232 for the height position of the substrate 3 in the measurement range using the roughness detection pattern 92. The plurality of roughness detection value candidates 232 can include a roughness detection value detected without pitch deviation and a roughness detection value detected with pitch deviation of one period or more. Next, the controller 20 obtains a plurality of fine detection value candidates 231 for the height position of the substrate 3 in the measurement range using the fine detection pattern 91.

[0054] Next, the controller 20 specifies the fine detection value candidate 235 of the pair having the difference dmin (the minimum difference d of the height position) from among the plurality of pairs each including one of the plurality of roughness detection value candidates 232 and one of the plurality of fine detection value candidates 231. The identified fine detection value candidate 235 is closest to the actual height position 230. Therefore, the controller 20 obtains the specified fine detection value candidate 235 as the fine detection value.

[0055] Considering the combination of the plurality of roughness detection value candidates 232 and the plurality of fine detection value candidates 231, the measurement range is an interval 236 from the reference state until the period of the fine detection pattern 91 and the period of the roughness detection pattern 92 are each an exact integer multiple. Therefore, while improving the respective measurement accuracies of the fine detection pattern 91 and the roughness detection pattern 92, it is possible to further expand the measurement range of the fine detection pattern 91.

[0056] Further, by making both the fine detection pattern 91 and the roughness detection pattern 92 periodic patterns, it is possible to use the same height calculation method for each of the fine detection pattern 91 and the roughness detection pattern 92. Therefore, since it is not necessary to have a plurality of processors (not shown) in the controller 20, it is possible to reduce the cost by simplifying the processor, and it is possible to improve the processing speed by a single processing.

[0057] <Fourth Embodiment>

[0058] As shown in Figure 2 , the exposure apparatus 100 transfers the pattern of the original 1 to each of the plurality of shot regions of the substrate 3. Referring to the flowchart of Figure 11 , the method of exposing the substrate by the exposure apparatus 100 will be described.

[0059] First, in step S21, the substrate 3 is transferred to the exposure device 100, and in step S22, the alignment of the substrate 3 is performed by the OA detection system 16. Next, in step S10, the surface position measurement of the substrate 3 according to the above method is performed by the measuring device 15, and the surface shape data as the measurement result is stored in the memory 22. Next, in step S23, the substrate 3 is positioned by the substrate stage 4 at a position for starting to scan the shot area to be exposed. At this time, the substrate stage 4 controls the position (focus) and inclination (tilt) of the substrate 3 in the Z direction based on the surface shape data of the substrate 3, so that the deviation amount between the surface position of the substrate 3 and the image plane of the projection optical system 6 is reduced. In step S24, the shot area to be exposed is scanned and exposed. In this scanning exposure, the controller 20 causes the substrate stage 4 to control the Z-axis position (focus) and inclination (tilt) of the substrate 3 so that the deviation amount from the image plane is reduced. Therefore, in the scanning exposure of each shot area, the surface of the substrate 3 can be matched with the image plane of the projection optical system 6 in synchronization with the scanning of the substrate 3. In step S25, the controller 20 determines whether there are any unexposed shot areas. If there are any unexposed shot areas, the process returns to step S10 to repeat the process for the next shot area. After exposure of all shot areas is completed, in step S26, the substrate 3 is unloaded from the exposure device 100.

[0060] By the above-mentioned exposure method, the exposure device 100 transfers the pattern of the original 1 to each of the plurality of shot areas of the substrate 3, such as Figure 2 As shown in . That is, a common pattern is transferred to each shot area. Therefore, measurement using the rough detection pattern can be performed only when measuring the height position of the substrate 3 for the first time. In addition, when it is pre-conceived that the height of the substrate 3 changes, a configuration can be adopted in which measurement using the rough detection pattern is not performed. Since the number of measurement points is reduced in this case, the capture speed of the image capture element and the height calculation speed in the controller are improved. Alternatively, the number of measurement points for height measurement using the fine detection pattern can be increased by the amount by which the number of measurement points is reduced. In this case, high-density height measurement can be performed without changing the height calculation speed.

[0061] <Example of the method for manufacturing an article>

[0062] For example, the article manufacturing method according to the embodiment of the present application is suitable for manufacturing an article such as a micro device (such as a semiconductor device) or an element having a micro structure. The article manufacturing method of the present embodiment includes a step of forming a latent image pattern on a photosensitive agent applied to a substrate using the exposure apparatus described above (a first step of exposing the substrate) and a second step of developing the substrate on which the latent image pattern is formed by such a step. Further, such a manufacturing method includes other well-known processes such as oxidation, deposition, evaporation, doping, planarization, etching, resist stripping, dicing, bonding, packaging, and the like. The article manufacturing method of the present embodiment has an advantage in at least one of performance, quality, productivity, and production cost of the article compared to a conventional method.

[0063] While the present application has been described with reference to exemplary embodiments, it is to be understood that the application is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

Claims

1. A measuring device, characterized in that: The measuring device is used to measure the height position of an object, and the measuring device includes: a light projector configured to project a coarse detection pattern and a fine detection pattern having a periodic pattern onto an object; a light receiver configured to image the coarse detection pattern and the fine detection pattern projected onto the object by the light projector; and a processor configured to determine a coarse detection value of a height position of the object based on the coarse detection pattern imaged by the light receiver, and to determine a fine detection value of the height position of the object based on the coarse detection value and the fine detection pattern imaged by the light receiver, The light projector is configured to project the coarse detection pattern and the fine detection pattern onto the object such that the coarse detection pattern surrounds the fine detection pattern.

2. The measuring device according to claim 1 , wherein the processor is configured to: determining a plurality of height position candidates based on a fine detection pattern received by the light receiver; and A height position candidate closest to the coarse detection value among the plurality of height position candidates is determined as the fine detection value.

3. The measuring device according to claim 1 , wherein the processor is configured to: determining a plurality of roughness detection value candidates based on the roughness detection pattern; determining a plurality of fine detection value candidates based on the fine detection pattern; as well as A fine detection value candidate of a pair having the smallest height position difference is determined as a fine detection value from among a plurality of pairs, each of which includes one of the plurality of coarse detection value candidates and one of the plurality of fine detection value candidates.

4. The measuring device according to claim 1, wherein the light projector is configured to: project a fine detection pattern onto a fine detection area, which is an area in the surface of the object for determining a fine detection value using the fine detection pattern; and project a coarse detection pattern onto a coarse detection area adjacent to the fine detection area. 5 . The measuring device according to claim 1 , wherein the light projector is configured to perform projection of the fine detection pattern and projection of the rough detection pattern such that a time interval for projecting the rough detection pattern overlaps at least a portion of a time interval for projecting the fine detection pattern. 6 . The measuring device according to claim 4 , wherein the fine detection pattern is projected onto an area in the surface of the object that is larger than the fine detection area and includes the fine detection area. The measuring device according to claim 1 , wherein the roughness detection pattern is a non-periodic pattern. 8 . The measurement device according to claim 1 , wherein the fine detection pattern includes a periodic pattern having a first period, and the rough detection pattern includes a periodic pattern having a second period longer than the first period.

9. An exposure device, characterized in that: The exposure device is used to project the pattern of the original onto the substrate through the projection optical system and expose the substrate, and the exposure device includes: The measuring device according to any one of claims 1 to 8, arranged to measure the height position of a substrate; and A controller is configured to control the position of the substrate based on a result measured by the measuring device so that a deviation amount of the height position from the image plane of the projection optical system is reduced.

10. A method for manufacturing an article, characterized in that The method comprises: exposing a substrate using the exposure apparatus according to claim 9; and The exposed substrate is developed, wherein An article is fabricated from the developed substrate.

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