JP2020115172A - Lithography device, measurement method, and method for manufacturing article - Google Patents

Abstract

To provide a technique advantageous for measuring flatness of a substrate holding surface of a stage while reducing reduction in throughput.SOLUTION: A lithography device forming patterns in each of a plurality of substrates includes a stage having a substrate holding surface holding a substrate, a substrate conveyance part which carries the substrate from the substrate holding surface and carries the substrate into the substrate holding surface, a detection part which detects the respective heights of the plurality of parts in the substrate holding surface and a processing part which determines the flatness of the substrate holding surface, in which the processing part allows the detection part to perform processing of detecting the height of a partial part among the plurality of parts in a period during until the substrate is carried into the substrate holding surface after the substrate has been carried from the substrate holding surface by changing parts to be detected in each of the periods, and thereby determines the respective heights of the plurality of parts and determines the flatness of the substrate holding surface based on the respective determined heights of the plurality of parts.SELECTED DRAWING: Figure 4

Description

The present invention relates to a lithographic apparatus, a metrology method, and an article manufacturing method.

A lithographic apparatus that forms a pattern on a substrate such as a semiconductor wafer or a glass plate is used for manufacturing a semiconductor device, a liquid crystal display device, or the like. In a lithographic apparatus, the flatness of a substrate held by a stage can affect the accuracy with which a pattern is formed on the substrate. In Patent Document 1, the height is measured at a plurality of measurement points in the shot area of the substrate, and based on the measurement result, the position of the substrate is controlled so that the surface of the substrate is located on the image plane of the projection optical system. There is disclosed an exposure apparatus that does.

JP, 2011-86777, A

In a lithographic apparatus, the flatness of a substrate holding surface of a stage that holds a substrate may change over time due to, for example, wear or distortion. In this case, the flatness of the substrate held by the stage changes depending on the flatness of the substrate holding surface of the stage, and the position of the substrate is determined based on the measurement results of the heights at a plurality of measurement points on the substrate. Even if the control is performed, the accuracy of forming the pattern on the substrate may be insufficient. Therefore, in the lithographic apparatus, it is preferable to measure the flatness of the substrate holding surface of the stage and perform maintenance (adjustment) on the substrate holding surface. On the other hand, the flatness of the substrate holding surface of the stage needs to be measured in a state where the stage does not hold the substrate. In other words, during the measurement of the flatness of the substrate holding surface, the pattern forming process cannot be performed on the substrate, which may be disadvantageous in terms of throughput.

Therefore, an object of the present invention is to provide an advantageous technique for measuring the flatness of the substrate holding surface of the stage while reducing the decrease in throughput.

In order to achieve the above object, a lithographic apparatus according to one aspect of the present invention is a lithographic apparatus that forms a pattern on each of a plurality of substrates, the stage having a substrate holding surface for holding the substrate, and the substrate holding apparatus. A substrate carrying section that carries out the substrate from the surface and carries the substrate into the substrate holding surface, a detecting section that detects the height of each of a plurality of locations on the substrate holding surface, and a plane of the substrate holding surface A processing unit that determines a degree, wherein the processing unit is a part of the plurality of locations in a period from when the substrate is unloaded from the substrate holding surface to when the substrate is loaded into the substrate holding surface. The process of detecting the height of the location, by changing the detection target location for each period to perform the detection unit, to obtain the height of each of the plurality of locations, each of the plurality of locations obtained The flatness of the substrate holding surface is determined based on the height of the substrate.

Further objects and other aspects of the present invention will be made clear by the preferred embodiments described below with reference to the accompanying drawings.

According to the present invention, for example, it is possible to provide an advantageous technique for measuring the flatness of the substrate holding surface of the stage while reducing the decrease in throughput.

Schematic showing the configuration of the exposure apparatus The figure which shows the processing flow which is done with the exposure device Diagram for explaining the processing performed in the exposure apparatus The figure which shows the processing flow about the measurement processing of the flatness of the board|substrate holding surface which concerns on 1st Embodiment. Figure showing a display example of flatness information View of the substrate stage (substrate holding surface) seen from above The figure which shows the processing flow about the measurement processing of the flatness of the board|substrate holding surface which concerns on 2nd Embodiment. The figure which shows the processing flow about the measurement processing of the flatness of the board|substrate holding surface which concerns on 3rd Embodiment. View of the substrate stage (substrate holding surface) seen from above

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. The following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiment, not all of the 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 components are designated by the same reference numerals, and duplicated description will be omitted.

In the following embodiments, an exposure apparatus that exposes a substrate will be used as a lithographic apparatus that sequentially forms a pattern on each of a plurality of substrates, but the present invention is not limited to this. For example, in an imprint apparatus that forms a pattern of an imprint material on a substrate using a mold, or a lithographic apparatus such as a drawing apparatus that irradiates a substrate with a charged particle beam (beam) to form a pattern on the substrate, The present invention can be applied.

<First Embodiment>
The exposure apparatus 100 according to the first embodiment of the present invention will be described. The exposure apparatus 100 exposes the substrate W (specifically, the resist coated on the substrate) with the light that has passed through the original M and the projection optical system to expose the original M on each of the plurality of shot areas on the substrate W. The process of transferring the pattern (exposure process) is performed. The exposure apparatus 100 of the present embodiment can sequentially perform the exposure processing on each of the plurality of substrates W, and the exposure method may be a step-and-scan method or a step-and-scan method. It may be a repeat system. Further, as the original M, for example, a mask or reticle may be used, and as the substrate W, for example, a glass plate or a semiconductor wafer may be used.

Next, a configuration example of the exposure apparatus 100 will be described. FIG. 1 is a schematic diagram showing the configuration of an exposure apparatus 100 of this embodiment. The exposure apparatus 100 includes a projection optical system 10 that projects the pattern of the original plate M onto the substrate W. The original stage 20 is arranged on the object plane side of the projection optical system 10, and the substrate stage 30 is arranged on the image plane side of the projection optical system 10. The original stage 20 and the substrate stage 30 can be independently driven, and their positions are measured by the laser interferometer 50.

The original stage 20 includes an original chuck 21 and an original driving mechanism 22, and is configured to hold the original M and move it. The original plate chuck 21 holds the original plate M by, for example, a vacuum chuck or an electrostatic chuck. The original plate drive mechanism 22 supports the original plate chuck 21, and can be configured to be movable in each of the X-axis direction and the Y-axis direction and rotatable in the XY plane. The X-axis direction and the Y-axis direction are two directions orthogonal to each other in a plane perpendicular to the optical axis of the light emitted from the projection optical system 10 to the substrate W. An observation optical system 40 for observing the substrate W via the original M and the projection optical system 10 is arranged above the original stage 20, and illumination for illuminating the original M is provided above the observation optical system 40. An optical system 41 is arranged.

The substrate stage 30 includes a substrate chuck 31 and a substrate driving mechanism 32, and is configured to hold and move the substrate W. The substrate chuck 31 has a substrate holding surface that contacts the substrate W and holds the substrate W, and holds the substrate W by, for example, a vacuum chuck or an electrostatic chuck. In the case of the present embodiment, the substrate chuck 31 includes a chuck base 31a and a chuck attachment 31b, and the upper surface of the chuck attachment 31b can function as a substrate holding surface. The chuck attachment 31b is, for example, divided (divided) into a plurality of partial areas, and the flatness can be adjusted for each partial area. The flatness can be adjusted by, for example, exchanging or polishing the chuck attachment 31b for each partial region, or inserting a spacer (shim) for each partial region of the chuck attachment 31b.

Further, the substrate driving mechanism 32 has a Y-axis stage 32a, an X-axis stage 32b and a θZ stage 32c arranged on a stage surface plate 33, supports the substrate chuck 31, and also supports the substrate chuck 31 (substrate W). Is movable in six axis directions. The 6-axis directions are the X-axis direction, the Y-axis direction, the Z-axis direction (the direction parallel to the optical axis of the light emitted from the projection optical system 10 to the substrate W), and the rotation directions around the respective axes. ..

The laser interferometer 50 includes a laser head 51, a first mirror 52 attached to the original plate drive mechanism 22, and a second mirror 53 attached to the substrate drive mechanism 32 (θZ stage 32c), and the original plate M and the substrate. The relative position (relative displacement) with W is measured. Specifically, the laser light emitted from the laser head 51 is branched by the half mirror 54, a part of the laser light is reflected by the mirror 55 and is incident on the first mirror 52, and the remaining laser light is reflected by the second mirror. It is incident on 53. Since the laser light reflected by the first mirror 52 and the laser light reflected by the second mirror 53 interfere with each other by passing through the half mirror again, based on the interference pattern, the original plate drive mechanism 22 (original plate M). The relative position between the substrate drive mechanism 32 (substrate W) can be measured.

The control unit CNT is configured by, for example, a computer having a CPU, a memory, and the like, and integrally controls the operation of the entire apparatus (that is, controls the exposure processing of the substrate W. In the case of the present embodiment, the control unit CNT, As will be described later, it has a function as a processing unit that determines the flatness of the substrate holding surface of the substrate stage 30.

The exposure apparatus 100 also includes a substrate transfer unit 60 and a detection unit 70. The substrate transport unit 60 performs a carry-out process of carrying out the substrate W from the substrate stage 30 (substrate holding surface) and a carry-in process of carrying in a new substrate W to the substrate stage 30 (substrate holding surface). The substrate transfer unit 60 can include, for example, a transfer robot having a hand 61 that holds the substrate W and an arm 62 that drives the hand 61. The detection unit 70 sequentially detects the height (position in the Z-axis direction) of each of a plurality of locations on the substrate holding surface of the substrate stage 30. In the case of the present embodiment, the detection unit 70 performs the process of detecting the height of one location on the substrate holding surface by step-moving the substrate stage 30 for each of the plurality of locations on the substrate holding surface. The height of each of the plurality of points can be detected. The detector 70 may include, for example, a laser interferometer. Here, in the present embodiment, the detection unit 70 is provided in the projection optical system 10, but the present invention is not limited to this, and the detection unit 70 may be arbitrarily arranged within the exposure apparatus 100.

In the exposure apparatus 100, the flatness of the substrate holding surface of the substrate stage 30 may change with time due to, for example, wear or distortion. In this case, since the flatness of the substrate W held by the substrate stage 30 changes according to the flatness of the substrate holding surface of the substrate stage 30, the pattern forming accuracy on the substrate W may be insufficient. .. Therefore, in the exposure apparatus 100, it is preferable to measure the flatness of the substrate holding surface of the substrate stage 30 and perform maintenance (adjustment) on the substrate holding surface. On the other hand, the flatness of the substrate holding surface needs to be measured in the state where the substrate stage 30 does not hold the substrate W, that is, the state where the substrate W is not mounted on the substrate stage 30. That is, during the measurement of the flatness of the substrate holding surface, the pattern forming process on the substrate W cannot be performed, which may be disadvantageous in terms of throughput.

Therefore, in the exposure apparatus 100 of the present embodiment, in the period from when the substrate W is unloaded from the substrate holding surface of the substrate stage 30 by the substrate transport unit 60 to when the substrate W is loaded in the substrate holding surface, The height of some of the plurality of locations is detected (detection processing). Then, by performing such a detection process by changing the detection target location for each period, the height of each of the plurality of locations on the substrate holding surface is obtained, and based on the obtained height of each of the plurality of locations. Determine the flatness of the substrate holding surface. That is, the exposure apparatus 100 of the present embodiment uses the period during which the substrate W on the substrate stage 30 is exchanged, that is, the period between pattern formations for a plurality of substrates W, to increase the height of a plurality of locations on the substrate holding surface. Detection is performed separately. This makes it possible to measure the flatness of the substrate holding surface while reducing the decrease in throughput.

Next, a processing flow performed by the exposure apparatus 100 of this embodiment will be described with reference to FIGS. 2 and 3. FIG. 2 is a diagram showing a processing flow performed by the exposure apparatus 100 of this embodiment. Each step of the processing flow shown in FIG. 2 can be performed under the control of the control unit CNT. Further, FIG. 3 is a diagram for explaining processing performed by the exposure apparatus 100 of the present embodiment. In FIG. 3, the device configuration is simplified as compared with FIG. 1 for the sake of easy understanding.

In S11, as shown in FIG. 3A, the control unit CNT moves the substrate stage 30 to the substrate loading position, and loads the substrate W onto the substrate stage 30 (substrate holding surface) by the substrate transport unit 60. .. In S12, as shown in FIG. 3B, the control unit CNT sets the substrate stage 30 so that the target shot area of the substrate W (shot area where exposure processing should be performed) is arranged below the projection optical system 10. The target shot area is moved and exposure processing (pattern formation) is performed. In S13, the control unit CNT determines whether or not the exposure processing has been performed on all of the plurality of shot areas on the substrate W on the substrate stage 30. If there is a shot area that has not been subjected to the exposure processing, the process returns to S12, and the shot area that has not been subjected to the exposure processing is set as the target shot area, and the exposure processing is performed. On the other hand, if exposure processing has been performed for all shot areas, the process proceeds to S14.

In S14, as shown in FIG. 3C, the control unit CNT moves the substrate stage 30 to the substrate unloading position, and unloads the substrate W from the substrate stage 30 (substrate holding surface) by the substrate transporting unit 60. .. In the case of the present embodiment, the substrate loading position and the substrate unloading position are the same position, but may be different positions. In S15, the control unit CNT determines whether or not there is a substrate W (next substrate W) to be subjected to the exposure processing next. If there is no next substrate W, the process ends. On the other hand, if there is a next substrate W, the process proceeds to S16. In S16, as shown in FIG. 3D, the control unit CNT moves the substrate stage 30 below the detection unit 70, and at some of the plurality of positions on the substrate holding surface of the substrate stage 30, Height detection is performed by the detection unit 70 (detection processing). Then, when the new substrate W is loaded onto the substrate stage 30, the detection process of S16 is ended, and the process returns to S11.

Next, the measurement processing (measurement method) of the flatness of the substrate holding surface will be described with reference to FIG. FIG. 4 is a diagram showing a processing flow for measuring the flatness of the substrate holding surface. Each step of the processing flow shown in FIG. 4 can be performed under the control of the control unit CNT.

S21 to S24 are the detection process performed in S16 of the process flow shown in FIG. In steps S21 to S24, the height detection by the detection unit 70 at a plurality of positions on the substrate holding surface is performed every period from when the substrate W is unloaded from the substrate holding surface to when the substrate W is loaded into the substrate holding surface. In addition, the detection target portion is changed and divided. Then, when the steps of S21 to S24 are completed, S11 of the processing flow shown in FIG. 2 may be started to carry in a new substrate W. Note that, hereinafter, a period from when the substrate W is unloaded from the substrate holding surface to when the substrate W is loaded into the substrate holding surface may be referred to as a “replacement period of the substrate W”.

In S21, the control unit CNT determines whether the substrate W is carried out by the substrate transport unit 60 and the substrate W is carried out from the substrate holding surface of the substrate stage 30. The control unit CNT can determine that the substrate W is unloaded from the substrate holding surface when the substrate W on the substrate stage 30 (substrate holding surface) is held by the hand 61 of the substrate transfer unit 60, for example. When it is determined that the substrate W has not been unloaded from the substrate holding surface, S21 is repeated, and when it is determined that the substrate W has been unloaded from the substrate holding surface, the process proceeds to S22.

In S22, the control unit CNT identifies a portion (hereinafter, may be referred to as an unexecuted portion) where the height detection by the detection unit 70 has not been performed among a plurality of portions on the substrate holding surface of the substrate stage 30. To do. In S23, the control unit CNT performs height detection by the detection unit 70 with the unexecuted portion of the substrate holding surface specified in S22 as the detection target portion. In S24, the control unit CNT determines whether or not the loading process of the substrate W by the substrate transport unit 60 is started. For example, the control unit CNT can determine that the loading process of the substrate W is started when the hand 61 of the substrate transport unit 60 holds the new substrate W. When it is determined that the loading process of the substrate W is not yet started, the process returns to S22, and when it is determined that the loading process of the substrate W is started, the process proceeds to S25.

S25 to S27 are steps of determining and notifying the flatness of the substrate holding surface of the substrate stage 30. The steps S25 to S27 may be performed by the control unit CNT (processing unit), but may be performed by an information processing device (computer) provided outside the exposure apparatus 100. The steps S25 to S27 may be performed in parallel with the steps S11 to S15 of the processing flow shown in FIG.

In S25, the control unit CNT determines whether or not the height detection by the detection unit 70 has been performed for all of the plurality of locations on the substrate holding surface of the substrate stage 30. If the height detection has not been performed for all the locations, the process returns to S21, and if the height detection has been performed for all the locations, the process proceeds to S26. In S26, the control unit CNT determines the flatness of the substrate holding surface based on the height of each of the plurality of positions on the substrate holding surface of the substrate stage 30. For example, the control unit CNT calculates the height distribution of the substrate holding surface obtained by approximating the heights of the plurality of positions on the substrate holding surface, the average value and the standard deviation calculated from the heights of the plurality of positions. , May be determined as the flatness of the substrate holding surface.

In S27, the control unit CNT notifies the information regarding the flatness of the substrate holding surface determined in S26 (hereinafter, may be referred to as flatness information). The notification of the flatness information may be performed, for example, by displaying the flatness information on a display unit (display) provided in the exposure apparatus 100. Alternatively, the flatness information may be output to an external computer of the exposure apparatus 100 (displayed on a display unit of the external computer). Here, the control unit CNT specifies the abnormal portion of the substrate holding surface based on the flatness of the substrate holding surface, and notifies (displays) the flatness information such that the abnormal portion and other portions can be distinguished. Is preferred. For example, the control unit CNT can specify, as the abnormal portion, a portion of the height distribution of the substrate holding surface, which has a height whose difference from the average height is larger than the allowable range. Further, when the abnormal portion is specified, the control unit CNT may display a display prompting the maintenance of the substrate stage 30 (the substrate holding surface, the chuck attachment 31b) together with the flatness information. FIG. 5 is a diagram showing a display example of flatness information. In the display example of the flatness information shown in FIG. 5, as the flatness of the substrate holding surface, the height distribution 34 of the substrate holding surface is represented by contour lines, and the abnormal portion 35 of the substrate holding surface is shown by hatching. ..

Here, based on the flatness of the substrate holding surface determined in S26, the control unit CNT performs height detection when determining the flatness of the substrate holding surface next time (that is, in the next measurement process). You may set (change) the arrangement|positioning of the some location which should be performed. For example, when an abnormal portion is specified on the substrate holding surface, the control unit CNT controls the substrate holding surface so as to increase the number of places where the detection unit 70 should perform height detection in the abnormal portion of the substrate holding surface. You may set up the arrangement of two or more places. Further, the control unit CNT sets the arrangement of a plurality of locations on the substrate holding surface so as to reduce the number of locations where the height detection should be performed by the detection unit 70 in the portion other than the abnormal portion of the substrate holding surface. May be.

As described above, the exposure apparatus 100 according to the present embodiment performs height detection at a plurality of positions on the substrate holding surface of the substrate stage 30 by dividing it for each replacement period of the substrate W. This makes it possible to measure (determine) the flatness of the substrate holding surface while reducing the decrease in throughput.

<Second Embodiment>
A second embodiment according to the present invention will be described. In the present embodiment, another example regarding the processing of measuring the flatness of the substrate holding surface will be described. In the first embodiment, the example in which the height detection by the detection unit 70 is performed at as many locations as possible during the replacement period of the substrate W has been described. In the present embodiment, an example will be described in which height detection is performed a preset number of times (that is, for a preset number of locations) during the replacement period of the substrate W. The present embodiment basically inherits the first embodiment except for the processing of measuring the flatness of the substrate holding surface. The configuration of the exposure apparatus 100 and the processing flow of the exposure apparatus 100 shown in FIG. Is the same as in the first embodiment.

Here, as shown in FIG. 6, the substrate holding surface of the substrate stage 30 (chuck attachment 31b) is divided (divided) into a plurality of partial regions 36, and the flatness can be adjusted for each partial region 36. Has been done. FIG. 6 is a view of the substrate stage 30 (substrate holding surface) in a state in which the substrate W is not held, viewed from above. In the present embodiment, as shown in FIG. 6, at least one portion P where the height detection by the detection unit 70 should be performed is set in each of the plurality of partial areas 36 (in the example shown in FIG. Point P is set). Then, during the replacement period of one substrate W (for each replacement period), the height of the position P included in one partial region 36 among the plurality of positions on the substrate holding surface is measured.

FIG. 7 is a diagram showing a processing flow for measuring the flatness of the substrate holding surface according to the present embodiment. Each step of the processing flow shown in FIG. 7 can be performed under the control of the control unit CNT.

S31 to S34 are the detection process performed in S16 of the process flow shown in FIG. In S31, the control unit CNT determines whether the substrate W is carried out by the substrate transfer unit 60 and the substrate W is carried out from the substrate holding surface of the substrate stage 30. When it is determined that the substrate W has not been unloaded from the substrate holding surface, S31 is repeated, and when it is determined that the substrate W has been unloaded from the substrate holding surface, the process proceeds to S32. In S<b>32, of the plurality of partial areas on the substrate holding surface, one partial area 36 for which the height detection by the detection unit 70 has not been performed is specified. In S33, the control unit CNT performs height detection by the detection unit 70, with the location included in the one partial region 36 specified in S32 as the detection target location. In S34, the control unit CNT determines whether or not height detection has been performed for all the locations included in the one partial area specified in S32. If height detection has not been performed for all the locations, the process returns to S31. On the other hand, when the heights have been detected for all the locations, the process proceeds to S35, and S11 of the processing flow shown in FIG. 2 is started.

In the example shown in FIG. 6, height detection is performed for four locations P included in the partial area 36a in the first detection processing, and height detection is performed for four locations P included in the partial area 36b in the second detection processing. Height detection is performed. Similarly, in the third detection process, the heights of the four places P included in the partial area 36c are detected, and in the fourth detection process, the heights of the four places P included in the partial area 36d are detected. Detection is done. In this manner, the height detection by the detection unit 70 is sequentially performed by changing the partial region 36 for each detection process (that is, for each replacement period of the substrate W).

S35 to S36 are steps of determining and notifying the flatness of the substrate holding surface of the substrate stage 30. Since the steps S35 to S36 are the same as steps S26 to S27 in the processing flow shown in FIG. 4, the description thereof will be omitted. Here, in S36, the control unit CNT may identify the abnormal portion of the substrate holding surface for each partial region 36 of the substrate holding surface. This allows the user to easily recognize which partial area 36 the height should be adjusted.

As described above, in the present embodiment, the height of each of the plurality of positions on the substrate holding surface of the substrate stage 30 is detected for each partial area 36 whose height can be adjusted individually. As a result, similarly to the first embodiment, it is possible to measure (determine) the flatness of the substrate holding surface while reducing the decrease in throughput.

<Third Embodiment>
A third embodiment according to the present invention will be described. In the present embodiment, another example regarding the processing of measuring the flatness of the substrate holding surface will be described. In the present embodiment, an example will be described in which when an abnormal portion is specified based on the flatness of the substrate holding surface, the height of the abnormal portion is detected in more detail. The present embodiment basically inherits the first and second embodiments except for the processing of measuring the flatness of the substrate holding surface. The configuration of the exposure apparatus 100 and the exposure apparatus 100 shown in FIG. The processing flow of is the same as that of the first embodiment.

FIG. 8 is a diagram showing a processing flow for measuring the flatness of the substrate holding surface according to the present embodiment. Each step of the processing flow shown in FIG. 8 can be performed under the control of the control unit CNT. Note that S41 to S46 of the processing flow shown in FIG. 8 are the same steps as S21 to S26 of the processing flow shown in FIG. 4, and therefore description thereof will be omitted here.

In S47, the control unit CNT determines whether there is an abnormal portion of the substrate holding surface based on the flatness of the substrate holding surface determined in S46. As described above, the control unit CNT can specify, as the abnormal portion, a portion of the height distribution of the substrate holding surface, which has a height whose difference from the average height is larger than the allowable range. When there is an abnormal portion on the substrate holding surface, the process proceeds to S48, and when there is no abnormal portion, the process proceeds to S50.

In S48, the control unit CNT sets a plurality of second locations where the detection unit 70 should detect the height of the abnormal portion of the substrate holding surface. The plurality of second locations may be set at a narrower interval than the preset plurality of locations (first locations). FIG. 9 is a view of the substrate stage 30 (substrate holding surface) in a state in which the substrate W is not held, as seen from above, and shows an arrangement example of a plurality of locations where height detection should be performed. FIG. 9A shows an arrangement example of a plurality of preset first places P1, and FIG. 9B shows a plurality of second places newly set in S48 in the identified abnormal portion 35. The example of arrangement of P2 is shown.

In S49, the control unit CNT performs height detection by the detection unit 70 for each of the plurality of second locations set in S48, and the height of each of the plurality of first locations on the substrate holding surface and the plurality of second locations. The flatness of the substrate holding surface is updated (determined) based on the height of each of the points. In this step S49, it is preferable to perform the same steps as steps S41 to S46 for the plurality of second locations. That is, it is preferable to perform the detection process of detecting the heights of some of the second locations during the replacement period of the substrate W by changing the detection target locations for each period.

In S50, the control unit CNT notifies the information (flatness information) regarding the flatness of the substrate holding surface determined in S49. The step S50 is the same step as the step S27 of the processing flow shown in FIG. 4, and thus detailed description thereof will be omitted.

As described above, in the present embodiment, when an abnormal portion is specified based on the flatness of the substrate holding surface, a plurality of second locations are set for the abnormal portion, and height detection is performed in more detail. .. This allows the user to grasp in detail what flatness the specified abnormal portion of the substrate holding surface has, and therefore the maintenance of the substrate stage 30 (substrate holding surface) can be performed accurately. You can

<Embodiment of Manufacturing Method of Article>
The method for producing an article according to the embodiment of the present invention is suitable for producing an article such as a microdevice such as a semiconductor device or an element having a fine structure, for example. The method of manufacturing an article according to the present embodiment includes a step of forming a pattern on a substrate using the above-mentioned lithographic apparatus (exposure apparatus), and a step of processing the substrate on which the pattern is formed in the step. Further, the 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 the present embodiment is advantageous in at least one of the performance, quality, productivity, and production cost of the article as compared with the conventional method.

The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Therefore, the following claims are attached to open the scope of the invention.

10: Projection optical system, 20: Original stage, 30: Substrate stage, 60: Substrate transport section, 70: Detection section, CNT: Control section (processing section)

Claims (12)

A lithographic apparatus for forming a pattern on a substrate, comprising:
A stage having a substrate holding surface for holding the substrate;
A substrate transfer unit that carries out the substrate from the substrate holding surface and carries the substrate into the substrate holding surface;
A detection unit that detects the height of each of a plurality of locations on the substrate holding surface,
A processing unit for determining the flatness of the substrate holding surface,
Including
The processing unit performs a process of detecting the height of a part of the plurality of positions in a period from when the substrate is unloaded from the substrate holding surface to when the substrate is loaded into the substrate holding surface, The height of each of the plurality of locations is determined by changing the detection target location for each period and causing the detection unit to determine the height of each of the plurality of locations. A lithographic apparatus, characterized in that it determines a flatness. The substrate holding surface is divided into a plurality of partial regions whose height can be adjusted individually,
Each of the plurality of partial regions includes at least one location where the detection unit should detect the height,
The lithographic apparatus according to claim 1, wherein the processing unit causes the detection unit to detect the height of the at least one location included in one partial region for each period. The lithographic apparatus according to claim 2, wherein the processing unit changes, for each of the periods, a partial region in which the height is to be detected by the detection unit. The processing unit, based on the determined flatness of the substrate holding surface, sets the arrangement of the plurality of locations whose heights should be detected when determining the flatness of the substrate holding surface next. A lithographic apparatus according to any one of claims 1 to 3, characterized in that The processing unit identifies an abnormal portion of the substrate holding surface based on the determined flatness of the substrate holding surface, and increases the number of places where the detection unit should detect the height in the abnormal portion. The lithographic apparatus according to claim 4, further comprising: setting the arrangement of the plurality of locations whose heights should be detected when determining the flatness of the substrate holding surface. The processing unit identifies an abnormal portion of the substrate holding surface based on the determined flatness of the substrate holding surface, and causes the detection unit to detect a height in a portion other than the abnormal portion of the substrate holding surface. 6. The arrangement of the plurality of places where heights are to be detected when determining the flatness of the substrate holding surface next is set so as to reduce the number of power places. A lithographic apparatus according to claim 1. The processing unit identifies an abnormal portion of the substrate holding surface based on the determined flatness of the substrate holding surface, and identifies a plurality of second locations having a smaller space than the plurality of locations with respect to the abnormal portion. The flatness of the substrate holding surface is updated based on a result of setting and detecting the height of each of the plurality of second locations by the detection unit during the period. 6. The lithographic apparatus according to any one of 6, The processing unit causes the detection unit to perform a process of detecting the height of a part of the second places in the period by changing the detection target place for each period. Lithographic apparatus. The lithographic apparatus according to claim 1, wherein the processing unit notifies the determined flatness of the substrate holding surface. The processing unit identifies an abnormal portion of the substrate holding surface based on the flatness of the substrate holding surface, and notifies the flatness of the substrate holding surface such that the abnormal portion and other portions can be distinguished. A lithographic apparatus according to claim 9, characterized in that A measuring method for measuring the flatness of a substrate holding surface of a stage for holding a substrate,
An unloading step of unloading the substrate from the substrate holding surface,
A carrying-in step of carrying in the substrate onto the substrate holding surface,
A measurement step of measuring the flatness of the substrate holding surface,
Including
The measurement step includes a detection step of detecting a height of a part of a plurality of locations on the substrate holding surface in a period from the unloading step to the loading step, and a detection target location for each period. The measuring method is characterized in that the flatness of the substrate holding surface is determined based on the height of each of the plurality of locations obtained by performing the detecting step instead. Forming a pattern on a substrate using the lithographic apparatus according to claim 1.
A step of processing the substrate on which the pattern is formed in the step,
An article manufacturing method comprising: manufacturing an article from the processed substrate.

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