JP2018004860A - Alignment device, exposure device, and alignment method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform appropriate alignment adjustment without being affected by heat or the like. SOLUTION: In an exposure apparatus whose alignment can be adjusted by an alignment camera 80, a calibration scale 62 in which a plurality of calibration mark CMs are lined up is attached to an end of a table 52, and a reference plate 72 provided with a reference mark SM is used as a calibration mark CM. It is attached to the table 52 so that the reference mark SM is on the same line. Then, the reference camera 70 having the same field center of the X-direction position coordinates with respect to the alignment camera 80 is fixed to the camera base 45. During the camera calibration process, the camera position shift calculated by imaging the calibration mark CM with the alignment camera 80 based on the position shift amount of the calibration scale 62 (reference mark SM) calculated by imaging the reference mark SM with the reference camera 70. Correct the amount. [Selection diagram] Fig. 2

Description

  The present invention relates to an alignment (positioning) apparatus incorporated in an exposure apparatus and the like, and more particularly to calibration of the position of an alignment camera.

  In an exposure apparatus or the like, in order to accurately align a work object such as a substrate (hereinafter referred to as a workpiece), an alignment mark provided on the workpiece is imaged with an alignment camera, and the detected position of the actual alignment mark is detected. By comparing with the design (theoretical) position, the displacement amount of the workpiece position due to the conveyance accuracy or the like is detected. Then, based on the detected displacement amount, workpiece position adjustment and the like are performed.

  Usually, the workpiece size and the position of the alignment mark vary depending on the product type, and the alignment camera is mounted so as to be movable along the sub-scanning direction. For this reason, the visual field center position of the camera lens is deviated from the original center position due to pitching, yawing, and feed error of the camera driving mechanism. In order to calibrate this, a scale provided with a calibration mark indicating the reference position is attached to the stage, and the calibration mark is imaged with an alignment camera to detect a positional deviation of the camera (see, for example, Patent Document 1).

  On the other hand, in an exposure apparatus or the like, the exposure position may be shifted due to heat generation due to driving of the light source, driving of the transport stage, or a change in temperature. In order to solve this problem, the temperature of the apparatus is detected by a temperature detector, and the exposure position is corrected based on the correlation between the apparatus temperature obtained by prior measurement and the exposure position variation (see Patent Document 2). In this case, the exposure position is corrected in consideration of the temperature-dependent position shift of the calibration scale.

JP 2005-316461 A JP 2014-197136 A

  The temperature change of the apparatus varies depending on the use state, the accumulated use time, and the like, and it is difficult to uniquely derive the actual exposure position deviation from the correlation by the prior measurement. Even if the exposure position is corrected in consideration of the previously measured temperature information, it does not coincide with the actual displacement amount, and the exposure position cannot be accurately corrected. In particular, in an exposure apparatus or the like that requires a micron order or submicron order, a difference between an estimated workpiece position variation and an actual workpiece position variation causes a misalignment that cannot be overlooked.

  Therefore, it is required to accurately calibrate the camera position so that the position shift does not occur due to the influence of heat or the like regardless of the usage status of the apparatus.

  The alignment apparatus of the present invention is applicable to an exposure apparatus and the like, and is attached to at least one alignment camera that images an alignment mark provided on a workpiece and a stage unit that moves in a predetermined direction with respect to the apparatus main body. And a calibration scale in which a plurality of calibration marks imaged by the alignment camera are arranged.

  The workpiece is mounted on the stage unit and becomes a processing target. For example, a substrate or the like is mounted on the stage unit. Further, the apparatus main body part represents a fixed base part of an apparatus in which an alignment apparatus is incorporated, such as a pedestal / base on which a stage part is mounted, or a support that supports an exposure head and an optical system. Move relative to the body part.

  The alignment apparatus of the present invention includes a misalignment measuring unit capable of detecting a position change of a calibration scale or a predetermined calibration mark with respect to the apparatus main body when the stage unit is positioned at a predetermined position. The alignment apparatus can correct the positional deviation amount of the calibration scale based on the positional fluctuation amount detected by the positional deviation measuring unit.

  Unlike an alignment camera that cannot detect the position fluctuation of the calibration mark due to its own movement mechanism, etc., the position deviation measuring section that does not cause a position fluctuation with respect to the apparatus main body at least in the stage moving direction is a stage section. When a member such as a table expands or contracts due to the influence of heat or the like, it is possible to detect a change in position of the calibration scale or the calibration mark.

  That is, the position deviation measuring unit is configured not to change its position with respect to the coordinate system defined for the apparatus main body, and the calibration scale or the calibration is used depending on the coordinate system used when correcting the position of the alignment camera using the calibration scale. It is possible to detect a change in the position of the mark. For example, the position variation of the calibration scale or the calibration mark when the stage unit is positioned at the position where the calibration mark is measured by the alignment camera may be detected.

  As a configuration of the misalignment measuring unit, for example, it can be configured by an imaging unit (such as a camera) different from the alignment camera. Considering that the displacement of the alignment camera is caused by the movement mechanism of the alignment camera, the displacement measurement unit is fixed to the apparatus main body at least in the alignment camera movement direction (for example, the sub-scanning direction) and is provided on the stage unit. In other words, it is possible to configure the reference mark that changes its position with respect to the apparatus main body due to the influence of the heat of the stage portion or the like by an imaging unit capable of imaging.

  Considering that the expansion and contraction of the member such as the stage portion differs depending on the location, it is desirable to be able to detect the position variation in the state where the calibration mark is imaged by the alignment camera. Therefore, it is preferable to provide the reference mark so as to follow the alignment line of the plurality of calibration marks.

  Various arrangements can be adopted as the arrangement arrangement of the reference marks. For example, a reference member provided with a reference mark can be attached to the stage portion. In this case, by disposing the reference member near the calibration scale, the position fluctuation amount of the reference mark can be reliably matched with the position fluctuation amount of the calibration scale or the calibration mark.

  On the other hand, instead of providing a dedicated member for the reference mark, the reference mark may be included in the calibration scale. For example, in consideration of providing an imaging unit outside the movement range of the alignment camera, it is possible to provide a reference mark next to both ends of a plurality of configuration marks.

  As a fixing location of the imaging unit with respect to the apparatus main body, the imaging unit can be fixed to the camera base unit that supports the alignment camera. For example, if the alignment camera and the camera constituting the imaging unit are the same product and have the same optical characteristics, they may be installed at the same height as the alignment camera and the reference mark may be set at the same height as the calibration mark.

  When member expansion / contraction caused by the heat of the stage portion varies depending on the location, it is preferable to align the calibration scale mounting location and the reference mark installation location. For example, the calibration scale and the reference mark can be provided on the stage on which the work is mounted, or on an original calibration scale support provided near the table.

  An alignment method according to another aspect of the present invention includes imaging a plurality of alignment marks provided on a workpiece with an alignment camera, and a plurality of calibration scales provided on a calibration unit attached to a stage unit that moves in a predetermined direction with respect to the apparatus main body. A method in which a calibration mark is imaged by an alignment camera, and a reference mark different from the calibration mark provided on the stage unit is imaged by a camera different from the alignment camera fixed to the apparatus main body. The positional deviation amount of the calibration mark can be corrected from the deviation amount.

  According to the present invention, appropriate alignment adjustment can be performed without being affected by heat or the like.

It is a schematic side view of the exposure apparatus which is this embodiment. It is the schematic plan view seen from the exposure apparatus. It is the figure which showed the calibration scale and reference | standard board attached to a table. It is a block diagram of an exposure apparatus. It is the flowchart which showed the camera position calibration process performed by the control part. It is the figure which showed the modification of the stage part of exposure apparatus.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic side view of an exposure apparatus according to this embodiment. FIG. 2 is a schematic plan view of the exposure apparatus as viewed from above.

  The exposure apparatus 10 includes a gantry 15 and a support 40 installed on the upper surface 15S of the gantry 15. The support body 40 includes a rectangular support base 42 and leg portions 43A, 43B, 44A, 44B provided at four corners thereof, and the leg portions 43A, 43B, 44A, 44B are fixed to the gantry 15. . An exposure head 20 and a light source unit 30 are provided on the upper surface 42 </ b> S of the support base 42.

  Guide rails 60A and 60B are arranged on the upper surface 15S of the gantry 15 so as to be parallel to each other at a predetermined interval along the longitudinal direction of the gantry 15. It extends between the portions 44A and 44B to the other end. The guide rails 60A and 60B are provided with a stage unit 50 that is movable along the guide rails 60A and 60B.

  The stage unit 50 includes a table 52 on which a substrate (workpiece) W is mounted, and a stage moving mechanism 55 that supports the table 52 from below and moves the table 52 along the X, Y, and Z directions. The stage moving mechanism 55 includes an X stage mechanism 56 that moves the stage unit 50 along the guide rails 60A and 60B, and a fine movement stage mechanism 54 that moves in the Y direction and rotates around the Z axis.

  On the top surface 15S of the gantry 15, an XY coordinate system with respect to the apparatus is defined, and the Z direction is defined as the vertical (vertical) direction thereof. The guide rails 60 </ b> A and 60 </ b> B are arranged along the X direction, and a linear scale 58 for detecting the position of the stage unit 50 in the X direction is installed on the gantry 15. The rectangular table 52 is provided on the stage unit 50 such that the end surface 52L in the longitudinal direction and the end surface 52T perpendicular thereto are parallel to the X direction and the Y direction, respectively.

  A plate (hereinafter referred to as a camera base) 45 extending in the Y direction is fixed to the side surface of the support 40 and the legs 44A and 44B on the legs 44A and 44B side of the support 40, that is, on the center side. A guide mechanism 46 that moves the alignment camera 80 in the Y direction is mounted on the surface of the guide plate 45 opposite to the support 40. The guide mechanism 46 is constituted by, for example, a ball screw mechanism, and moves the alignment camera 80 by a camera driving unit provided with a motor (not shown). Here, the alignment camera 80 is composed of two alignment cameras 80A and 80B that are separated by a predetermined distance.

  As shown in FIG. 2, a plurality of alignment marks (here, nine) AM are regularly arranged at predetermined intervals on the substrate W placed at a predetermined position of the table 52. The alignment camera 80 can image each alignment mark AM by moving the stage unit 50 in the X direction and moving the alignment camera 80 in the Y direction.

  On the table 52, a camera position calibration scale (hereinafter referred to as a calibration scale) 62 is installed along one end face 52T parallel to the camera base 45. The calibration scale 62 is provided with a plurality of (here, ten) calibration marks CM arranged along the table end surface 52T, that is, along the Y direction. The alignment camera 80 can image each calibration mark CM by moving the stage unit 50 and moving the alignment camera 80.

  Apart from the calibration scale 62, a rectangular plate (hereinafter referred to as a reference plate) 72 on which one mark (hereinafter referred to as a reference mark) SM is formed is attached to the table 52. The reference mark SM is on the same line where the calibration marks CM of the calibration scale 62 are arranged. A camera 70 (hereinafter referred to as a reference camera) different from the alignment camera 80 is fixed to the camera base 45 at the same height as the alignment camera 80.

  The reference camera 70 is held by a holding unit 71 attached to the camera base 46 in a moving range along the Y direction of the alignment camera 80, that is, a position retracted from the imaging range. It is possible to image the mark SM. The position of the reference camera 70 in the X direction with respect to the camera base 46 is fixed at the same position as that of the alignment camera 80. That is, the reference camera 70 is attached to the camera base 46 via the holding unit 71 so that the visual field center of the alignment camera 80 and the visual field center of the reference camera 70 have the same position coordinates in the X direction. .

  FIG. 3 is a diagram showing a calibration scale and a reference plate attached to the table.

  The calibration scale 62 is made of glass, and has a chromium film on which a calibration mark CM is drawn. The pitch at which the calibration marks CM are arranged is determined according to the visual field size of the alignment camera 80 and the like. The calibration mark CM is sized and shaped so that the mark position coordinates can be accurately obtained when imaged by the alignment camera 80. Here, it is formed in a cross shape so that the angle error can be detected.

  The calibration scale 62 is installed in a recess provided on the table end surface 52T side, and its height is determined so that the surface of the calibration scale 62 is flush with the surface of the substrate W (see FIG. 2). . Like the calibration scale 62, the reference plate 72 is made of glass, and a cross-shaped reference mark SM having the same shape and size as the calibration mark CM is formed on the surface thereof. The reference plate 72 is attached to the table 52 so that the reference mark SM is positioned on the same line as the calibration mark CM. The surface of the reference plate 72 is also flush with the surface of the substrate W.

  Here, the reference camera 70 is configured by a product of the same type as the alignment camera 80, and imaging characteristics such as optical magnification and field size and appearance characteristics such as size are the same as those of the alignment camera 80. As described above, since the height of the mounting position of the alignment camera 80 and the mounting position of the reference camera 70 is the same, the image of the calibration mark CM and the reference mark SM obtained by imaging is an image of the same size.

  FIG. 4 is a block diagram of the exposure apparatus.

  The control unit 25 controls the overall operation of the exposure apparatus such as the exposure operation, alignment adjustment, and illumination of the exposure apparatus 10. When the light source 32 is turned on by the light source control unit 31, the illumination light enters a DMD (Digital Micro-mirror Device) 24 via the optical system 23.

  The exposure control unit 34 converts pattern data (vector data) transmitted from the workstation into raster data, and transmits the raster data (exposure data) to the DMD driving unit 22. The DMD driving unit 22 performs ON / OFF control of each micromirror of the DMD 24 based on raster data so as to project pattern light according to the exposure position. The light reflected by the DMD 24 is imaged as pattern light on the surface of the substrate W by the projection optical system 25.

  A stage driving unit (moving mechanism) 55 provided with a motor or the like drives the fine movement stage mechanism 54 and the X stage mechanism 56 shown in FIG. 1, and moves the stage unit 50, that is, the table 52 in the X and Y directions. The position detector 59 including the linear scale 58 (see FIG. 1) detects the position coordinates of the table 52 with respect to the gantry 15 (that is, the exposure apparatus body that is one structure including the support 40).

  The camera driving unit 82 drives and controls the alignment camera 80 to move the alignment camera 80 according to the alignment line of the alignment marks AM on the substrate W when performing alignment adjustment. As shown in FIG. 3, on the substrate W, three alignment marks AM are formed along both ends and the central lines a1 to a3.

  When performing alignment adjustment, the alignment cameras 80A and 80B move along the Y direction so as to be positioned on the lines a1 to a3. The alignment mark AM is imaged by moving the table 52 in the X direction so that the alignment mark AM is positioned below the alignment camera 80.

  The image processing unit 83 detects the position of the alignment mark AM based on the imaging signals output from the alignment cameras 80A and 80B. Specifically, the shift of the alignment mark center position from the center of the visual field of alignment camera 80A80B is detected. The alignment control unit 35 controls the exposure control unit 34 based on the received position information and corrects the raster data so as to compensate for substrate deformation and the like.

  Further, when the alignment camera 80 images the calibration mark CM, the image processing unit 83 detects the amount of positional deviation from the center of the visual field of the calibration mark CM. The camera calibration unit 37 calculates a correction amount based on the camera position deviation amount.

  Furthermore, the image processing unit 83 can detect the amount of positional deviation of the reference mark SM from the center of the field of view based on the imaging signal from the reference camera 70. The camera calibration unit 37 calculates a correction amount (hereinafter referred to as a scale correction amount) calculated based on the positional deviation of the calibration mark CM. The alignment control unit 35 corrects the raster data based on the correction amount including the scale correction amount.

  Here, the position fluctuation of the calibration scale 62, that is, the calibration mark CM with respect to the apparatus main body, that is, the gantry 15 and the support 40 will be described.

  The alignment cameras 80A and 80B are attached to the guide mechanism 46 so as to be movable along the Y direction. There are attachment and assembly errors, and the alignment cameras 80A and 80B are reciprocated by the guide mechanism 46. Due to the position error of the guide mechanism 46, the camera axis angle change, etc., the position of the center of the visual field is deviated from the designed position.

  In order to correct this misalignment of the visual field center, that is, the misalignment of the alignment cameras 80A and 80B, the position of the calibration mark CM is measured, and the position of the alignment camera 80 is determined from the difference between the actual measurement position and the original mark position. A deviation amount (that is, an error in the positional relationship between the alignment camera 80 and the support base 42 that fixes the exposure head 20) is obtained. The measurement of the positional deviation amount of the alignment camera 80 is based on the position of the calibration scale 62. That is, it is assumed that the position coordinates of the calibration scale 62 with respect to the gantry 15 and the support base 42 which is a part of the support body 40 do not change.

  However, the positional deviation of the calibration scale 62 (calibration mark CM) itself may occur depending on the use state of the exposure apparatus 10. If the stage unit 50 is reciprocated over a long period of time while the exposure apparatus 10 is in use, heat is applied to the fine movement stage mechanism 54 and the table 52 of the stage unit 50 due to the heat generated by the motor of the X stage mechanism 56. Expansion and deformation occur. Further, the heat of the light source unit 30 and the exposure head 20 generated during the exposure operation may affect the stage unit 50.

  When the table 52 is thermally expanded along the X direction due to the influence of such heat, the position of the calibration scale 62 is changed. In particular, since the expansion change appears more at the end surface 52T than at the center of the table 52, the position of the calibration scale 62 is likely to change.

  Therefore, even if the position with respect to the gantry 15 is detected by the linear scale 58, there is a position variation that cannot be ignored in the alignment adjustment, that is, the pattern accuracy, near the end surface 52T of the table 52 that is separated from the X stage mechanism 56 in the height direction and the X direction. May have occurred.

  Even if the correction of the camera position deviation by the calibration scale 62 described above is performed in this state, the correction amount is calculated in a state in which the position error of the calibration scale 62 is included, so that the alignment adjustment cannot be performed correctly. On the other hand, since the camera position shift occurs in the alignment camera 80, the position shift of the calibration scale 62 cannot be detected by the alignment camera 80 having an error.

  Therefore, in the present embodiment, the reference mark SM of the reference plate 72 installed near the calibration scale 62 is imaged by the reference camera 70 that is uniquely provided for measuring the positional variation of the calibration scale 62 (calibration mark CM). . Since the reference mark SM is formed on the same line as the calibration mark CM of the calibration scale 62 along the Y direction, it can be considered that the position fluctuation similar to the position fluctuation of the calibration scale 62 (calibration mark CM) occurs. .

  Therefore, a positional deviation amount is obtained by comparing the position coordinates of the reference mark SM to be measured with the position coordinates of the designed (ideal) reference mark SM, and this is added (subtracted) to the camera positional deviation correction amount. Thus, accurate alignment adjustment can be performed.

  FIG. 5 is a flowchart showing camera position calibration processing executed by the control unit. The camera position calibration process can be executed for each lot or for each substrate. For example, when the number of alignment mark rows is larger than the number of alignment cameras, it is necessary to move the alignment camera in the Y-axis direction.

  First, the alignment camera 80 is moved to the Y coordinate of the alignment mark AM. Here, the positions are aligned with the lines a1 to a3 shown in FIG. Then, the movement of the table 52 is controlled so that the calibration scale 62 becomes the design visual field center position of the alignment camera 80 (S101, S102). The position of the table 52 (stage unit 50) corresponds to a position where the visual field center position of the reference camera 70 matches the theoretical center position of the reference mark SM.

  Next, in the previous stage of the camera calibration process, the reference mark SM is imaged by the reference camera 70 (S103), and the amount of displacement of the reference mark SM from the visual field center position is calculated (S104). Here, the positional deviation in the X and Y directions and the rotation angle (θ) are calculated as the positional deviation amount. Since the center position of the reference camera 70 has the same X coordinate as the visual field center position of the alignment camera 80, that is, the visual field center position is on the same line along the Y direction, this deviation amount is calibrated to the calibration scale 62 ( This can be regarded as the amount of displacement of the calibration mark CM).

  Then, the alignment camera 80 measures the coordinates in the field of view of the calibration mark CM (S105), and calculates a value obtained by subtracting the positional deviation amount of the reference mark SM from the measured camera positional deviation amount as a correction amount for camera calibration (S105). S106). When the camera calibration process is completed, the position of the alignment mark AM on the substrate W is measured, and alignment adjustment is performed.

  As described above, according to the present embodiment, in the exposure apparatus 10 that can be aligned by the alignment camera 80, the calibration scale 62 in which a plurality of calibration marks CM are arranged is attached to the end of the table 52, and the reference plate provided with the reference marks SM. 72 is attached to the table 52 so that the calibration mark CM and the reference mark SM are on the same line. Then, the reference camera 70 having the same visual field center in the X-direction position coordinate with respect to the alignment camera 80 is fixed to the camera base 45. During the camera calibration process, based on the amount of displacement of the calibration scale 62 (reference mark SM) calculated by imaging the reference mark SM by the reference camera 70, the camera position displacement calculated by imaging the calibration mark CM by the alignment camera 80. Correct the amount.

  By arranging the installation location of the reference camera 70 and the reference plate 72 in the X direction in accordance with the installation location of the alignment camera 80 and the calibration scale 62, the calibration scale 62 due to the influence of heat or the like with a simple configuration and simple processing steps. The positional deviation of the calibration mark CM can be detected. In particular, by arranging the reference plate 72 near the calibration scale 62, it is possible to detect an accurate position variation.

  Instead of calculating the camera position deviation amount, the alignment camera position may be finely adjusted. Further, the positional deviation amount of the reference mark SM may be subtracted from the alignment correction amount at the time of alignment adjustment, or the raster data may be corrected in consideration of the positional deviation amount of the reference mark SM.

  Instead of providing a reference plate separately, a reference mark may be included in the calibration scale. For example, the longitudinal direction of the calibration scale may be extended and a reference mark may be provided at the end.

  As for the position shift detection, the correction amount for the camera position shift amount may be calculated only in the X direction where the position variation amount of the calibration scale is the largest. Further, as long as the position reproducibility in the X direction is ensured, a reference camera support member may be separately installed and moved to move the reference camera in the X or Y direction. Furthermore, the positional deviation amount of the calibration scale may be detected by imaging the four corner positions of the calibration scale without providing the reference mark.

  Regarding the calibration scale and the reference plate, the calibration scale and the reference plate may not be attached to the table, but may be fixed to other parts of the stage unit 50 and independent of the table. FIG. 6 is a view showing a modification of the stage unit of the exposure apparatus. A calibration scale 62 and a reference plate 72 are attached to the upper surface of a support base 92 attached to the X stage mechanism 56. By attaching to the end portion side of the stage unit 50, it is easy to detect the position variation.

  The installation location of the reference camera and the installation location of the reference plate are not limited to the above-described embodiment, and for example, imaging from below may be performed instead of imaging from above. Moreover, you may image with the camera etc. which are not the same kind as an alignment camera. Furthermore, the structure which does not provide a reference | standard board and an imaging part may be sufficient. For example, a light transmission unit such as a laser is radiated along the X direction, reflected by a mirror in the vertical direction, and received by a photosensor provided in the reflection direction. A positional deviation amount may be calculated.

  In the present embodiment, the alignment apparatus is configured in the exposure apparatus, but the present invention can also be applied to an alignment apparatus incorporated in an apparatus that performs work on a workpiece, such as a substrate inspection apparatus, a substrate drilling apparatus, or a component mounting apparatus. .

DESCRIPTION OF SYMBOLS 10 Exposure apparatus 50 Stage part 52 Table 62 Calibration scale 70 Reference camera (imaging part, scale position measurement part)
72 Reference plate (reference member)

Claims (10)

At least one alignment camera that images an alignment mark provided on the workpiece;
A calibration scale that is attached to a stage portion that moves in a predetermined direction with respect to the apparatus main body portion, and that has a plurality of calibration marks imaged by the alignment camera,
An alignment apparatus comprising: a misalignment measuring unit capable of detecting a position variation of the calibration scale or a predetermined calibration mark with respect to the apparatus main body when the stage unit is positioned at a predetermined position.   The alignment apparatus according to claim 1, wherein the misalignment measurement unit includes an imaging unit that is fixed to the apparatus main body portion at least with respect to an alignment camera moving direction and that can capture a reference mark provided on the stage unit. .   The alignment apparatus according to claim 2, wherein the reference mark is provided along an array line of the plurality of calibration marks. The positional deviation measuring unit has a reference member provided with the reference mark,
The alignment apparatus according to claim 2, wherein the reference member is disposed beside the calibration scale.   The alignment apparatus according to claim 2, wherein the reference mark is included in the calibration scale.   The alignment apparatus according to claim 2, wherein the imaging unit is fixed to a camera base unit that supports the alignment camera.   The said calibration scale and the said reference mark are provided in the calibration scale support stand provided in the table in which the said workpiece | work is mounted in the said stage part, or the said table. An alignment apparatus according to claim 1.   The alignment apparatus according to claim 1, wherein the positional deviation amount of the calibration scale is corrected based on a positional fluctuation amount detected by the positional deviation measuring unit.   An exposure apparatus comprising the alignment apparatus according to claim 1. The alignment mark provided on the work is imaged by the alignment camera,
A plurality of calibration marks provided on a calibration scale attached to a stage unit that moves in a predetermined direction with respect to the apparatus main body part is imaged by the alignment camera,
A method of imaging a reference mark different from the calibration mark provided on the stage unit by a camera different from the alignment camera fixed to the apparatus main body part,
An alignment method, wherein the positional deviation amount of the calibration mark can be corrected from the positional deviation amount of the reference mark.

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