MEASUREMENT APPARATUS, EXPOSURE APPARATUS, AND ARTICLE MANUFACTURING METHOD

Abstract

To provide a measurement device advantageous for simultaneously achieving a highly accurate measurement and a high throughput.SOLUTION: Provided is a measurement device for measuring a height position of an object. The measurement device includes: a light projecting part configured to project measurement light to the object; a light receiving part configured to receive the measurement light reflected at the object; and a processing part configured to obtain a height position of the object according to an image of the measurement light received at the light receiving part. The light projecting part projects to the object a rough detection pattern and a precise detection pattern having a cyclic pattern, and the processing part obtains the height position of the object according to the rough detection pattern and the precise detection pattern received at the light receiving part.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] Microdevices such as semiconductor devices and liquid crystal display devices are manufactured by a photolithography technique in which a pattern formed on an original is transferred to a substrate. An exposure apparatus used in a photolithography process has an original stage that supports the original and a substrate stage that supports the substrate, and transfers the pattern of the original onto the substrate via a projection optical system while sequentially moving the original stage and the substrate stage. In the exposure apparatus, every time each exposure target area (shot area) on the substrate is moved to an exposure position under the projection optical system by the substrate stage, a measurement device detects the deviation between the focus of the projection optical system and the surface position (height position) of the substrate, and the surface position of the substrate is corrected to achieve focus.

[0003] Patent Document 1 discloses measuring the height of a substrate, which is an object to be inspected, by using a measurement slit in which the slit length, slit interval, and slit width are changed stepwise. Patent Document 2 discloses simultaneously projecting a stripe pattern and a fixed pattern, and using the fixed pattern to obtain the phase of the stripe pattern. Patent Document 3 describes performing highly accurate height measurements with fewer iterations by measuring in advance the phase relationship between a long-period pattern and a short-period pattern. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6491833 [Patent Document 2] JP 2018-179665 A [Patent Document 3] Patent No. 5443303 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the technique of Patent Document 1 may be disadvantageous in terms of measurement accuracy because the pattern is changed within the test area. The technique of Patent Document 2 requires that the projection position of the stripe pattern and the projection position of the fixed pattern be aligned, so the density of measurement points may be reduced by the amount of the fixed pattern. Moreover, the technique of Patent Document 3 requires at least four steps of changing the phase of the periodic pattern and projecting it, so this may be disadvantageous in terms of measurement time, i.e., throughput.

[0006] The present invention provides a measuring apparatus that is advantageous in achieving both high-precision measurement and high throughput, for example. [Means for solving the problem]

[0007] According to one aspect of the present invention, there is provided a measurement apparatus for measuring a height position of an object, comprising: A rough pattern and a detailed pattern having a periodic pattern to the object projection A light-projecting unit for projecting light; The light projecting unit The object The rough inspection pattern and the fine inspection pattern projected onto the A light receiving unit; before By the light receiving unit Imaging A coarse detection value of the height position of the object is obtained based on the coarse detection pattern, and the coarse detection value and The image captured by the light receiving unit A precise detection value of the height position of the object is obtained based on the precise inspection pattern. Processing section and , the light projecting unit projects the rough test pattern on the object so as to surround the fine test pattern. A measuring device is provided. Effect of the Invention

[0008] According to the present invention, for example, it is possible to provide a measuring device that is advantageous in achieving both high-precision measurement and high throughput. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing the configuration of an exposure apparatus. [Diagram 2] 1A and 1B are diagrams illustrating examples of shot layouts and alignment marks on a substrate. [Diagram 3]FIG. 1A is a diagram showing the configuration of a measurement device, and FIG. 1B is a diagram showing an example of a mask configuration. [Figure 4] FIG. 13 is a diagram for explaining a pitch deviation in the prior art. [Diagram 5] 4A and 4B are diagrams showing examples of light projection patterns on a test object. [Figure 6] 4A and 4B are diagrams showing examples of light projection patterns on a test object. [Figure 7] FIG. 4 is a diagram for explaining a method for calculating a height position by a measurement device. [Figure 8] 4A and 4B are diagrams showing examples of light projection patterns on a test object. [Figure 9] 4A and 4B are diagrams showing examples of light projection patterns on a test object. [Figure 10] FIG. 4 is a diagram for explaining a method for calculating a height position by a measurement device. [Figure 11] 4 is a flowchart showing an exposure method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, the embodiments will be described in detail with reference to the attached drawings. Note that the following embodiments do not limit the invention according to the claims. Although the embodiments describe a number of features, not all of these features are essential to the invention, and the features may be combined in any manner. Furthermore, in the attached drawings, the same reference numbers are used for the same or similar configurations, and duplicated descriptions are omitted.

[0011] First Embodiment FIG. 1 is a diagram showing the configuration of an exposure apparatus 100 according to an embodiment to which the measurement apparatus of the present invention is applied. FIG. 2 is a diagram showing an example of a shot layout and alignment marks of a substrate 3. In this specification and the drawings, directions are shown in an XYZ coordinate system in which a horizontal plane is the XY plane. In general, the substrate 3 is placed on a substrate stage 4 so that its surface is parallel to the horizontal plane (XY plane). Therefore, in the following, directions that are orthogonal to each other in a plane along the surface of the substrate 3 are referred to as the X-axis and Y-axis, and a direction perpendicular to the X-axis and Y-axis is referred to as the Z-axis. In the following, 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 rotation direction around the X-axis, the rotation direction around the Y-axis, and the rotation direction around the Z-axis are referred to as the θx direction, the θy direction, and the θz direction, respectively.

[0012] 1, the exposure apparatus 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 illuminates the original 1 held on the original stage 2 with exposure light. The exposure apparatus 100 further includes a projection optical system 6 that projects and exposes the pattern of the original 1 illuminated with the exposure light onto the substrate 3 held on the substrate stage 4, and a controller 20 that provides overall control of the operation of the exposure apparatus. The controller 20 can include, for example, a CPU 21 and a memory 22. The memory 22 stores various control data, a control program for the exposure apparatus executed by the CPU 21, and the like.

[0013] The exposure apparatus 100 can be, for example, a scanning exposure apparatus (scanner) that exposes the substrate 3 while moving the original 1 and the substrate 3 synchronously with each other in a scanning direction (e.g., the Y direction). Alternatively, the exposure apparatus 100 can be an exposure apparatus (stepper) of a type that exposes the substrate 3 while the original 1 is fixed, and then moves the substrate 3 stepwise to expose the next shot area.

[0014] A predetermined illumination area on the original 1 is illuminated with exposure light having a uniform illuminance distribution by the illumination optical system 5. A mercury lamp, a KrF excimer laser, an ArF excimer laser, an F2 laser, or the like can be used as a light source in the illumination optical system 5. Alternatively, in order to manufacture finer semiconductor elements, the illumination optical system 5 may emit extreme ultraviolet light (EUV light) with a wavelength of several nm to several hundred nm.

[0015] The master stage 2 is movable within the XY plane and can be slightly rotated in the θz direction. The master stage 2 is driven by a master stage driving device (not shown) such as a linear motor, and the master stage driving device is controlled by the control unit 20. A mirror 7 is provided on the master stage 2. A laser interferometer 9 for the XY directions is provided at a position opposite the mirror 7 to measure the position of the mirror 7. The two-dimensional position and rotation angle of the master 1 on the master stage 2 are measured in real time by the laser interferometer 9, and the measurement results are output to the control unit 20. The control unit 20 controls the master stage driving device based on the measurement results of the laser interferometer 9 to position the master stage 2 (i.e., the master 1).

[0016] 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 with a projection magnification of, for example, 1 / 4 or 1 / 5.

[0017] The substrate stage 4 includes a θz tilt stage that holds the substrate 3 via a substrate chuck (not shown), an XY stage (not shown) that supports the θz tilt stage, and a base (not shown) that supports 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 a control unit 20. A mirror 8 that moves together with the substrate stage 4 is provided on the substrate stage 4. A laser interferometer 10 for measuring the XY directions and a laser interferometer 12 for measuring the Z direction are provided at positions facing the mirror 8. The positions of the substrate stage 4 in the XY directions and θz are measured in real time by the laser interferometer 10, and the measurement results are output to the control unit 20. The positions of the substrate stage 4 in the Z direction, θx and θy, are measured in real time by the laser interferometer 12, and the measurement results are output to the control unit 20. The control unit 20 controls the substrate stage driving device based on the measurement results of the laser interferometers 10 and 12 to position the substrate stage 4 (i.e., the substrate 3).

[0018] An original alignment detection system 13 is provided near the original stage 2. The original alignment detection system 13 detects an original reference mark (not shown) of the original 1 and a substrate-side reference mark 17 (see FIG. 2) on a stage reference plate 11 on the substrate stage 4. The original alignment detection system 13 is equipped with a photoelectric conversion element such as a CCD camera, and detects reflected light from the original reference mark and the substrate-side reference mark 17. Based on the signal from the photoelectric conversion element, the original and the substrate are aligned. At this time, the relative positional relationship (X, Y, Z) between the original and the substrate can be aligned by adjusting the positions and focus of the original reference mark and the substrate-side reference mark 17. The substrate-side reference mark 17 may be of either a reflective type or a transmissive type. The stage reference plate 11 at the corner of the substrate stage 4 is set at approximately the same height as the surface of the substrate 3.

[0019] The off-axis (OA) detection system 16 includes an illuminator that irradiates measurement light onto a substrate alignment mark 19 (see FIG. 2) on the substrate 3 and an OA detection system reference mark 18 (see FIG. 2) on the stage reference plate 11. The OA detection system 16 further includes an internal photoreceiver that receives reflected light from these marks, and detects the positions of the substrate alignment mark 19 and the OA detection system reference mark 18.

[0020] The measuring device 15 as a focus-tilt detection system measures the surface position (height position) of the substrate 3 in the height direction (Z direction) by projecting measuring light onto the surface of the substrate 3, which is the test object (object), and receiving the measuring light reflected by the substrate 3. Here, the measuring device 15 is also configured to be controlled by the control unit 20, but the measuring device 15 may also be provided with a dedicated control unit.

[0021] The measurement device 15 will be described in detail with reference to Fig. 3(a). The measurement device 15 may include a light projecting unit 110 that projects measurement light onto the substrate 3, and a light receiving unit 120 that receives the measurement light reflected by the substrate 3. A signal of an image of the measurement light received by the light receiving unit 120 is transferred to a control unit 20 which is a processing unit, and the control unit 20 performs processing to determine the height position of the substrate 3 based on the received signal.

[0022] The light projecting section 110 may include a condenser lens 111, a mask 112, a lens 113, and a mirror 114. The light receiving section 120 may include a mirror 124, a lens 122, and an imaging section 123. The imaging section 123 may include an imaging element 121 such as a CCD or a CMOS. Light emitted from a light source 115 is condensed by a condenser lens 111 and illuminates a mask 112. A plurality of slits forming a pattern are formed in the mask 112, and the mask 112 forms measurement light from the light from the light source 115. The light passing through the plurality of slits of the mask 112 is incident on the substrate 3 at a predetermined angle of incidence via a lens 113 and a 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 of the mask 112 is formed on the substrate 3. The mask 112 and the substrate 3 may be in a Scheimpflug optical relationship using the lens 113. Thereby, the measurement accuracy can be improved by focusing the entire surface of the mask 112 on the substrate 3. Furthermore, when measuring the height of the substrate 3, the measurement value can be prevented from changing due to a local tilt of the substrate 3. The measurement light reflected by the substrate 3 is re-imaged on the image sensor 121 of the image capturing unit 123 via the mirror 124 and the lens 122, and a signal 125 of a slit image corresponding to the multiple slits of the mask 112 is obtained. The substrate 3 and the image sensor 121 may be in a Scheimpflug optical relationship using the lens 122. Thereby, the measurement accuracy can be improved by focusing the entire surface of the substrate 3 on the image sensor 121. Furthermore, when measuring the height of the substrate 3, the measurement value can be prevented from changing due to a local tilt of the substrate 3. The signal 125 is transferred to the control unit 20, which is a processing unit. The control unit 20 detects the positional deviation on the image sensor 121 of the received signal 125, thereby obtaining the position (height position) of the substrate 3 in the Z direction.

[0023] The light projecting unit 110 projects images of a plurality of slits of the mask 112 onto the substrate 3. Hereinafter, this is referred to as a "light projection pattern." With reference to FIG. 4, a light projection pattern 140 on the substrate 3 according to the conventional technology will be described. The measurement device precisely determines the height position based on the light projection pattern projected onto a predetermined precise inspection region 301 within the field of view 303 of the image sensor. In order for the measurement device to precisely measure the height of the precise inspection region 301 on the surface of the substrate 3, it is necessary to narrow the pattern interval 141 (FIG. 4(a)) of the light projection pattern 140 as much as possible. When the light projection pattern 140 is received by the light receiving unit 120, a pattern image 151 appears on the imaging surface of the image sensor 121 (FIG. 4(b)). When the height measurement is performed using each peak position of the signal of the pattern image 151, the number of measurement points increases by the amount of the increase in the number of peak positions 153 within the field of view 303 of the image sensor. In order to increase the number of measurement points in the precise inspection region 301, it is necessary to narrow the pattern interval 141.

[0024] However, when the pattern interval of the light projection pattern 140 is narrowed, the problem of "pitch deviation" may become prominent. For example, as shown in FIG. 4(c), the light projection pattern 140 may be shifted by one period in the precise inspection region 301 from the pattern in FIG. 4(a) due to a change in the height of the substrate 3. FIG. 4(d) shows a pattern image 151 received by the light receiving unit 120 at this time, which may be the same as FIG. 4(b). Therefore, even if the height of the substrate 3 changes, the detection value of the height in the precise inspection region 301 calculated by the control unit 20 may remain unchanged. In this way, when an error of one period or more occurs in the projection position of the light projection pattern having a periodic structure, the height cannot be measured accurately.

[0025] As a measure against such pitch deviation, in this embodiment, the light projecting unit 110 projects different types of light projection patterns onto the substrate 3. FIG. 3(b) shows a plan view of the mask 112. The mask 112 has a first region R1 and a second region R2. For example, the first region R1 may be a central region 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. A periodic fine inspection pattern is projected onto the substrate 3 by passing light from the light source 115 through the plurality of slits S1. One or more slits are formed in the second region R2. In the example of FIG. 3(b), a plurality of slits S2 are periodically arranged at intervals D2 larger than the interval D1 in the second region R2. A rough inspection pattern is projected onto the substrate 3 by passing light from the light source 115 through the plurality of slits S2.

[0026] The control unit 20 as a processing unit determines the height position of the substrate 3 based on the rough inspection pattern and the fine inspection pattern received by the light receiving unit 123. For example, the control unit 20 determines a coarse detection value of the height position of the substrate 3 based on the rough inspection pattern received by the light receiving unit 123. The control unit 20 then determines a fine detection value of the height position of the substrate 3 based on the obtained coarse detection value and the fine inspection pattern received by the light receiving unit 123.

[0027] FIG. 5 shows an example of a projection pattern projected onto the substrate 3 in this embodiment. In FIG. 5, the projection pattern 212 is composed of a precise inspection pattern 210 and a rough inspection pattern 220. The projection unit 110 projects both the precise inspection pattern 210 and the rough inspection pattern 220 using a mask 112 configured as shown in FIG. 3(b). The projection unit 110 may project the precise inspection pattern 210 and the rough inspection pattern 220 simultaneously, or may project the precise inspection pattern 210 and the rough inspection pattern 220 so that at least a part of a period during which the precise inspection pattern 210 is projected and a period during which the rough inspection pattern 220 is projected overlap each other. The precise inspection pattern 210 is projected onto a precise inspection region 301, and the rough inspection pattern 220 is projected onto a rough inspection region 302 adjacent to the precise inspection region 301. Both the precise inspection pattern 210 and the rough inspection pattern 220 are incident on a field of view 303 of the image sensor 121. The precise inspection pattern 210 and the rough inspection pattern 220 may be incident simultaneously on the field of view 303 of the image pickup element 121, or may be incident so that at least a part of a period during which the precise inspection pattern 210 is incident and a period during which the rough inspection pattern 220 is incident overlap. Note that the light projection pattern 212 varies in a direction in which the light projection unit 110 projects the pattern onto the substrate 3 (Y direction in a plan view seen from above in the Z direction) according to the height of the substrate 3, but it is not necessary that the entirety of the varied light projection pattern 212 fits within the field of view 303 of the image pickup element 121. It is sufficient that the control unit 20 can receive pattern light in a range that allows the control unit 20 to calculate the height position of each of the precise inspection pattern 210 and the rough inspection pattern 220.

[0028] The precise inspection pattern 210 and the rough inspection pattern 220 are configured with different patterns. In order to increase the number of measurement points in the precise inspection region 301, for example, the interval 211 of the precise inspection pattern 210 is smaller than the interval 221 of the rough inspection pattern 220. The interval 221 of the rough inspection pattern 220 is set so that the interval 211 of the rough inspection pattern 220 is smaller than the interval 221 of the rough inspection pattern 220 within a height variation range of the substrate 3 that is predetermined as the measurement range of the measuring device 100. 0 Therefore, the rough detection pattern 220 does not have a pitch shift (periodic error), and the rough detection value is uniquely determined.

[0029] As long as the control unit 20 can always perform height calculation for the variation of the light projection pattern 112 due to the height variation of the substrate 3 within the measurement range of the measurement device 100, the rough inspection pattern 220 may be a single pattern without periodicity. As an example, the rough inspection pattern 220 may be a dot pattern as shown in Fig. 6. Taking into consideration the position of the field of view 303 of the imaging element 121 on the substrate 3, the change in reflectance of the substrate 3, vignetting due to the internal structure, and the like, the dot pattern as the rough inspection pattern 220 may be arranged at multiple locations as shown in Fig. 6.

[0030] The precise test pattern 210 and the rough test pattern 220 are adjacent to each other, for example. Since the precise test pattern 210 and the rough test pattern 220 are adjacent to each other, it is possible to reduce a difference in measurement position between the measurement of the height of the substrate 3 using the precise test pattern 210 and the measurement of the height of the substrate 3 using the rough test pattern 220.

[0031] A method of calculating the height position executed by the control unit 20 will be described with reference to Fig. 7. The control unit 20 obtains a coarse detection value 233 of the height position of the board 3 by using the rough inspection pattern 220 in the rough inspection region 302. As described above, the rough inspection pattern 220 is a pattern that does not cause a pitch deviation (periodic error), so the coarse detection value 233 is uniquely determined. After that, the control unit 20 obtains a precise detection value of the height position of the board 3 based on the coarse detection value 233 and the precise inspection pattern 210. The precise detection value is obtained specifically as follows.

[0032] The control unit 20 determines a plurality of height position candidates 231 of the substrate 3 within the measurement range by using the precise inspection pattern 210 in the precise inspection region 301. The plurality of height position candidates 231 may include a height position detected without a pitch shift and a height position detected with a pitch shift of one period or more. Since the measurement position of the precise inspection pattern (precise inspection region 301) and the measurement position of the rough inspection pattern (coarse inspection region 302) are adjacent to each other, the coarse detection value 233 is close to the actual height position 230 of the substrate 3 in the precise inspection region 301. Therefore, the control unit 20 determines the height position candidate 231 having the smallest difference 234 from the coarse detection value 233 (closest to the coarse detection value 233) as the precise detection value.

[0033] This makes it possible to prevent erroneous detection due to pitch deviation, and achieves highly accurate detection of the height position. In addition, this measurement method does not require multiple light projections to determine the height position, as in the conventional technology, and is therefore advantageous in terms of throughput.

[0034] <Second embodiment> 8 shows an example of a light projection pattern on the test object in the second embodiment. When the height of the test object, the substrate 3, fluctuates, the position on the substrate 3 where the light projection pattern 112 is projected fluctuates. At this time, if the light projection pattern 112 deviates from the precise inspection region 301, measurement cannot be performed. Therefore, in this embodiment, the precise inspection pattern 210 is projected onto an area on the surface of the substrate 3 that is larger than the precise inspection region 301 and includes the precise inspection region 301, so that the precise inspection pattern 210 can always be observed in the precise inspection region 301 even if the height of the test object fluctuates.

[0035] In one example, the optical axis direction of the measurement light between the light projecting unit 110 and the light receiving unit 120 in a plan view of the precise inspection region 301 seen from above in the Z direction is assumed to be parallel to the Y direction. In this case, when the height of the precise inspection region 301 varies, the position on the precise inspection region 301 where the precise inspection pattern 210 is projected changes in the Y direction. Therefore, in order to always project the precise inspection pattern 210 onto the precise inspection region 301, the projection range of the precise inspection pattern 210 in the Y direction is set to be larger than the range of the precise inspection region 301 in the Y direction.

[0036] In this case, the rough test pattern 220 is arranged in the X direction with the fine test pattern 210 in between, as shown in FIG. Towards The rough inspection pattern 220 is disposed at a position spaced apart from the target object. In order to measure the height of the target object using the rough inspection pattern 220, the rough inspection pattern 220 must always be received by the image sensor 121 regardless of the height fluctuation of the precise inspection region 301. When the height of the target object fluctuates, the projection pattern 112 fluctuates in the Y direction, which is the optical axis direction of the measurement light in a plan view. Therefore, by disposing the rough inspection pattern 220 along the X direction perpendicular to the Y direction, which is the direction of the pattern fluctuation due to the fluctuation of the target object height, the required size of the image sensor 121 can be reduced. In general, the size and price of the image sensor are directly proportional to each other, so that the image sensor is preferably small in size. In addition, since an increase in the number of pixels of the image sensor increases the transfer speed and the calculation processing speed, which is disadvantageous in terms of measurement throughput, the image sensor is preferably small in size.

[0037] <Third embodiment> FIG. 9 shows an example of a precise inspection pattern 91 projected onto a precise inspection region 301 and a rough inspection pattern 92 projected onto a rough inspection region 302 around the precise inspection region 301. The precise inspection pattern 91 is a pattern having a first period, and the rough inspection pattern 92 is a pattern having a second period longer than the first period. Compared to the example of FIG. 5, the period of the rough inspection pattern 92 in FIG. 9 is shorter than that of the rough inspection pattern 220 in FIG. 5. Since the rough inspection pattern 92 has a shorter periodic pattern, the number of measurement points can be increased, and therefore height measurement can be performed with higher accuracy. By improving the accuracy of the height measurement of the rough inspection region 302 obtained using the rough inspection pattern 92, the height position of the precise inspection region 301 can be obtained more accurately from a plurality of height position candidates 231 selected using the precise inspection pattern 91.

[0038] 5, the period of the rough inspection pattern 220 is set to a length that does not cause a pitch deviation, but the period of the rough inspection pattern 92 in FIG. 9 is shorter than that, so there is a possibility that a pitch deviation occurs similarly to the fine inspection pattern 91. Therefore, in this embodiment, the height position is obtained as follows.

[0039] A method of calculating the height position in this embodiment will be described with reference to FIG. 10. The control unit 20 obtains a rough detection value of the height position of the substrate 3 by using the rough inspection pattern 92 in the rough inspection region 302. However, in this embodiment, the rough inspection pattern 92 may cause a pitch shift, so the height position is not uniquely determined. Therefore, the control unit 20 obtains a plurality of rough detection value candidates 232 related to the height position of the substrate 3 within the measurement range by using the rough inspection pattern 92. The plurality of rough detection value candidates 232 may include a rough detection value without a pitch shift and a rough detection value detected with a pitch shift of one period or more. Next, the control unit 20 obtains a plurality of fine detection value candidates 231 related to the height position of the substrate 3 within the measurement range by using the fine inspection pattern 91.

[0040] Next, the control unit 20 selects one of the multiple coarse detection value candidates 232 and multiple fine detection value candidates 231 Among a plurality of pairs with one of the above, a precision detection value candidate 235 of a pair having a difference dmin, which is the smallest difference d in the height position, is identified. The identified precision detection value candidate 235 is closest to the actual height position 230. Therefore, the control unit 20 determines the identified precision detection value candidate 235 as the precision detection value.

[0041] Multiple rough inspections Out Value candidate 232 and multiple refinements Out By considering a combination with the value candidate 231, the measurement range becomes a section 236 from the reference state to a section where the period of the precise test pattern 91 and the period of the rough test pattern 92 are just integer multiples, respectively. This makes it possible to further expand the measurement range of the precise test pattern 91 while improving the measurement accuracy of each of the precise test pattern 91 and the rough test pattern 92.

[0042] Moreover, by making both the precise inspection pattern 91 and the rough inspection pattern 92 periodic patterns, the same height calculation method can be applied to each of the precise inspection pattern 91 and the rough inspection pattern 92. This eliminates the need for the control unit 20 to have a plurality of processing units (not shown), which can reduce costs by simplifying the processing units and improve the processing speed by a single processing unit.

[0043] <Fourth embodiment> Exposure apparatus 100 transfers the pattern of original 1 onto each of a plurality of shot areas of substrate 3 as shown in Fig. 2. A method of exposing a substrate by exposure apparatus 100 will be described with reference to the flowchart in Fig. 11.

[0044] First, in S21, the substrate 3 is loaded into the exposure apparatus 100, and in S22, the substrate 3 is aligned by the OA detection system 16. Next, in S10, the measurement device 15 measures the surface position of the substrate 3 according to the above-mentioned method, and surface shape data, which is the measurement result, is stored in, for example, the memory 22. Next, in S23, the substrate 3 is positioned by the substrate stage 4 at a position for starting scanning of the shot area to be exposed. At that 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 of the surface position of the substrate 3 from the image plane of the projection optical system 6 is reduced. In S24, the shot area to be exposed is subjected to scanning exposure. In this scanning exposure, the control unit 20 controls the position (focus) and inclination (tilt) of the substrate 3 in the Z direction to the substrate stage 4 so that the deviation amount from the image plane is reduced. Thereby, in the scanning exposure of each shot area, the surface of the substrate 3 can be made to coincide with the image plane of the projection optical system 6 in synchronization with the scanning of the substrate 3. In S25, control unit 20 determines whether there is an unexposed shot area. If there is an unexposed shot area, the process returns to S10 and repeats the process for the next shot area. When exposure of all shot areas is completed, substrate 3 is unloaded from exposure apparatus 100 in S26.

[0045] The exposure apparatus 100 transfers the pattern of the original 1 to each of the multiple shot areas of the substrate 3 as shown in FIG. 2 by the above-mentioned exposure method. That is, a common pattern is transferred to each shot area. Therefore, the measurement using the rough inspection pattern may be performed only when the height position of the substrate 3 is measured for the first time. Also, if the height fluctuation of the substrate 3 is predicted in advance, the measurement using the rough inspection pattern may not be performed. In that case, the number of measurement points is reduced, so that the capture speed from the imaging element and the height calculation speed in the control unit are improved. Alternatively, the number of measurement points for height measurement using the precise inspection pattern may be increased by the amount of the reduction in the number of measurement points. In that case, high-density height measurement can be performed without changing the height calculation speed.

[0046] <Embodiment of the article manufacturing method> The article manufacturing method according to the embodiment of the present invention is suitable for manufacturing articles such as microdevices such as semiconductor devices and elements having a fine structure. The article manufacturing method of this embodiment includes a step of forming a latent image pattern on a photosensitive agent applied to a substrate using the above-mentioned exposure apparatus (a first step of exposing the substrate), and a second step of developing the substrate on which the latent image pattern has been formed in this step. Furthermore, this manufacturing method includes other well-known steps (oxidation, film formation, deposition, doping, planarization, etching, resist stripping, dicing, bonding, packaging, etc.). The article manufacturing method of this embodiment is advantageous in at least one of the performance, quality, productivity, and production cost of the article compared to conventional methods.

[0047] The invention is not limited to the above-described embodiments, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0048] 1: original, 2: original stage, 3: substrate, 4: substrate stage, 5: illumination optical system, 6: projection optical system, 15: measurement device, 20: control unit, 100: exposure device

Claims

1. A measuring device for measuring a height position of an object, comprising: a light projection unit that projects a rough inspection pattern and a detailed inspection pattern having a periodic pattern onto the object; a light receiving unit that captures the rough inspection pattern and the fine inspection pattern projected onto the object by the light projecting unit; a processing unit that determines a coarse detection value of a height position of the object based on the coarse inspection pattern imaged by the light receiving unit, and determines a fine detection value of a height position of the object based on the coarse detection value and the fine inspection pattern imaged by the light receiving unit, the light projecting unit projects the rough test pattern on the object so as to surround the fine test pattern. A measuring device characterized by:

2. 2. The measurement apparatus according to claim 1, wherein the light projecting unit has a lens for focusing an entire surface of a mask on which the rough inspection pattern and the detailed inspection pattern are formed, onto the object.

3. 3. The measuring apparatus according to claim 1, wherein the light receiving section has a lens for focusing the entire surface of the object onto an imaging element.

4. The processing unit includes: determining a plurality of height position candidates based on the detailed inspection pattern received by the light receiving unit; determining, from among the plurality of height position candidates, a value closest to the coarse detection value as the fine detection value; 4. The measuring device according to claim 1, wherein the measuring device is a measuring device for measuring a temperature of the object.

5. The processing unit includes: determining a plurality of roughly detected value candidates based on the roughly detected pattern; determining a plurality of precision detection value candidates based on the precision examination pattern; determining, as the fine detection value, a fine detection value candidate of a pair having a smallest difference in height position from among a plurality of pairs of one of the plurality of rough detection value candidates and one of the plurality of fine detection value candidates; 4. The measuring device according to claim 1, wherein the measuring device is a measuring device for measuring a temperature of the object.

6. 6. The measurement device according to claim 1, wherein the light projecting unit projects the precision test pattern onto a precision test region, which is a region on a surface of the object where the precision detection value is obtained using the precision test pattern, and projects the coarse test pattern onto a coarse test region adjacent to the precision test region.

7. 7. The measurement device according to claim 1, wherein the light projecting unit projects the fine test pattern and the rough test pattern such that a period for projecting the fine test pattern and a period for projecting the rough test pattern at least partially overlap with each other.

8. 7. The measurement apparatus according to claim 6, wherein the precision inspection pattern is projected onto an area on the surface of the object that is larger than the precision inspection area and that includes the precision inspection area.

9. 9. The measurement apparatus according to claim 1, wherein the precise inspection pattern has a periodic pattern having a first period, and the coarse inspection pattern has a periodic pattern having a second period longer than the first period.

10. A measuring device for measuring a height position of an object, comprising: a light projection unit that projects measurement light onto the object; a light receiving unit that receives the measurement light reflected by the object; a processing unit that determines a height position of the object based on an image of the measurement light received by the light receiving unit, the light projection unit projects a rough inspection pattern and a fine inspection pattern having a periodic pattern onto the object; the processing unit determines a coarse detection value of a height position of the object based on the coarse inspection pattern received by the light receiving unit, and determines a fine detection value of the height position of the object based on the coarse detection value and the fine inspection pattern; The processing unit includes: determining a plurality of roughly detected value candidates based on the roughly detected pattern; determining a plurality of precision detection value candidates based on the precision examination pattern; Among a plurality of pairs of one of the plurality of rough detection value candidates and one of the plurality of fine detection value candidates, a fine detection value candidate of a pair having a smallest difference in height position is obtained as the fine detection value. A measuring device characterized by:

11. 1. An exposure apparatus that projects a pattern of an original onto a substrate by a projection optical system to expose the substrate, comprising: The measurement device according to claim 1 , which is arranged to measure a height position of the substrate; a control unit that controls a position of the substrate based on a result of measurement by the measurement device so that a deviation amount of the height position from an image plane of the projection optical system is reduced; An exposure apparatus comprising:

12. A first step of exposing a substrate using the exposure apparatus according to claim 11; a second step of developing the substrate exposed in the first step; and manufacturing an article from the substrate developed in the second step.

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