Substrate supporting device and exposure device

Abstract

The purpose of the present invention is to provide an abutment support device capable of suppressing deformation of an abutment. A base support device (810) is provided with: a plurality of actuators (81b) which are disposed on an installation surface, support a base (81a) at each of a plurality of support points on the lower surface side of the base (81a), and generate a thrust force in the support direction with respect to the support points; a plurality of detection units (82) that detect a first position in the support direction of each of the plurality of support points with respect to the installation surface; and a control unit (CNT) that calculates an approximate plane of the lower surface of the base (81a) on the basis of the first positions detected by each of the plurality of detection units (82). And a control unit (81b) that calculates a second position in the support direction with respect to the installation surface for each of points at which an axis that passes through the support point and extends in the support direction intersects the approximate plane, and controls the plurality of actuators (81b) on the basis of the difference between the first position and the second position for each of the support points.

Description

Technical Field

[0001] This invention relates to a base support device and an exposure device. Background Technology

[0002] In the photolithography process, one of the manufacturing processes of electronic devices (micro-devices) such as semiconductor devices or liquid crystal display elements, in order to transfer and expose the pattern formed on the mask (marker) onto a glass plate (or wafer) coated with photoresist, a single-exposure type (static exposure type) exposure apparatus such as a stepper or a scanning exposure type exposure apparatus such as a scanning stepper is used.

[0003] In exposure apparatuses, to eliminate the effects of vibration and improve exposure accuracy such as the positioning and overlap accuracy of the mask stage and substrate stage, a vibration damping platform is disposed between the base component (platform) and the floor (setting surface) of the exposure apparatus. A vibration damping device has been proposed that actively controls the vibration of the vibration damping platform by using a sensor to detect the vibration of the platform and feeding back the detection signal to an actuator that applies a control force to the platform (e.g., Patent Document 1).

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2001-304332 Summary of the Invention

[0007] According to the first disclosure, the base support device includes: a plurality of actuators disposed on a mounting surface, each supporting the base at a plurality of support points on the lower surface side of the base and generating thrust relative to the support points in a support direction; a plurality of detection units that detect a first position of each of the plurality of support points in the support direction based on the mounting surface; and a control unit that calculates an approximate plane of the lower surface of the base based on the first positions detected by the plurality of detection units, calculates a second position of each point in the support direction based on the mounting surface at which an axis extending along the support direction through the support points intersects the approximate plane, and controls the thrust generated by each of the plurality of actuators based on the difference between the second position and the first position of each support point.

[0008] According to the second disclosure, the exposure apparatus includes: the aforementioned base support device; a mask stage capable of holding and moving a mask; and an optical platform supporting the mask stage and disposed on the base support device.

[0009] According to the third disclosure, the exposure apparatus includes the aforementioned base support device; a stage located on the base support device, capable of holding a substrate and moving it in the scanning direction; and a projection optical system located on the stage, wherein the control unit performs the following processing when moving the stage relative to the projection optical system in the scanning direction: detecting the first position; calculating the approximate plane; calculating the second position; and controlling the thrust generated by each of the plurality of actuators based on the difference between the second position and the first position of each of the support regions.

[0010] It should be noted that the configuration of the embodiments described below can be appropriately modified, and at least some components can be replaced with other components. Furthermore, the configuration elements that are not particularly limited in their arrangement are not limited to the configuration disclosed in the embodiments, and can be configured in a position that achieves their function. Attached Figure Description

[0011] Figure 1 This is a diagram that schematically illustrates the configuration of an exposure apparatus equipped with a vibration damping device according to one embodiment.

[0012] Figure 2 (A) is a top view of the vibration damping device viewed from the +Z direction. Figure 2 (B) is a diagram of the vibration damping device viewed from the -X direction.

[0013] Figure 3 This is a diagram used to illustrate the structure of a vibration damping device.

[0014] Figure 4 This is a block diagram illustrating an example of a subject's posture control method.

[0015] Figure 5 (A) is a graph showing the simulation results of the support point at the Z position (position 1) relative to the ground. Figure 5 (B) is a graph showing the calculated Z-position (second position) of the support point in the least squares plane based on the ground, calculated from the first position. Figure 5 (C) is a diagram showing the difference between the first and second positions of each support point.

[0016] Figure 6 This is a diagram showing the relationship between the Z-position (first position) of the support point relative to the ground and the Z-position (second position) of the support point in the least squares plane calculated based on the first position, using the XYZ orthogonal coordinate system.

[0017] Figure 7 This is a block diagram illustrating the control method of this embodiment.

[0018] Figure 8This is a graph showing the simulation results of the difference between the first position and the second position when the control method of this embodiment is applied.

[0019] Figure 9 (A) is a graph showing the moving speed of the substrate stage relative to time. Figure 9 (B) is a graph showing the moving speed of the mask stage relative to time. Figure 9 (C) ~ Figure 9 (F) are graphs comparing the difference between the first and second positions of each support point calculated based on the output of the position sensor during the control of the comparative example, and the difference between the first and second positions of each support point calculated based on the output of the position sensor during the control of this embodiment. Detailed Implementation

[0020] based on Figures 1-9 The description of (F) illustrates an exposure apparatus 10 equipped with a vibration damping device 81 in one embodiment.

[0021] (Composition of the exposure device 10)

[0022] Figure 1 This is a schematic diagram showing the configuration of the exposure apparatus 10 equipped with the vibration damping device 81 in this embodiment.

[0023] The exposure apparatus 10 is a scanning stepper (scanner) that transfers a pattern formed on the mask MSK onto the substrate P by driving the mask MSK and the substrate (e.g., a glass substrate) P in the same direction and at the same speed relative to the projection optical system PL. The substrate P is, for example, a rectangular glass substrate used in liquid crystal display devices (flat panel displays), with at least one side length or diagonal length of 500 mm or more.

[0024] Hereinafter, the direction in which the mask MSK and substrate P are driven during scanning exposure (scanning direction) is defined as the X-axis direction, the direction in the horizontal plane orthogonal to it is defined as the Y-axis direction, the direction orthogonal to the X-axis and Y-axis is defined as the Z-axis direction, and the rotation (tilt) directions around the X-axis, Y-axis, and Z-axis are defined as the θx direction, θy direction, and θz direction, respectively. Furthermore, the positions in the X-axis, Y-axis, and Z-axis directions are denoted as the X position, Y position, and Z position, respectively. Similarly, the positions in the θx direction, θy direction, and θz direction are denoted as the θx position, θy position, and θz position, respectively.

[0025] The exposure apparatus 10 includes an illumination system IOP, a mask stage MST for holding the mask MSK, a projection optics system PL, a main body 70 supporting these parts, a substrate stage PST for holding the substrate P, and a control device CNT for these parts. The control device CNT provides unified control over all components of the exposure apparatus 10.

[0026] The main body 70 includes a lower column (hereinafter referred to as the base) 81a, columns 72A and 72B, an optical platform 73, a support body 74, and a sliding guide 75.

[0027] The base 81a is supported by a passive mounting base (not shown) and multiple pneumatic mounting bases (actuators) 81b disposed on the ground (setting surface) F. The multiple pneumatic mounting bases 81b support the base 81a at multiple support points and generate thrust relative to the support points in the support direction (Z-axis direction). The passive mounting base is an air damper or the like, controlled to maintain approximately constant internal pressure. The base 81a and the multiple pneumatic mounting bases 81b constitute a vibration damping device 81.

[0028] Columns 72A and 72B are each frame-shaped, with column 72A positioned inside column 72B. An optical platform 73, for example, has a flat plate shape and is fixed to the top of column 72A. A support 74 is supported on the top of column 72B by means of a sliding guide 75. The sliding guide 75 includes an air ball lifter and a positioning mechanism, positioning the support 74 (i.e., the mask stage MST described later) relative to the optical platform 73 at an appropriate position in the X-axis direction.

[0029] The lighting system IOP is positioned above the main body 70. The lighting system IOP illuminates the mask MSK with illumination light IL.

[0030] The mask stage MST is supported on the support body 74. It has a patterned surface on which circuit patterns are formed. Figure 1 The mask MSK (lower surface) is fixed to the mask stage MST, for example, by vacuum adsorption (or electrostatic adsorption). The mask stage MST is driven by a drive system including a linear motor in the scanning direction (X-axis direction) with a specified stroke, and is slightly driven in the non-scanning directions (Y-axis direction and θz direction).

[0031] The position information (including rotation information in the θz direction) of the mask stage MST in the XY plane is measured by an interferometer system. The interferometer system illuminates a measuring beam onto a moving mirror (or a reflective surface processed from a mirror (not shown)) located at the end of the mask stage MST, and receives the reflected light from the moving mirror, thereby measuring the position of the mask stage MST. The measurement result is supplied to the control device CNT, which drives the mask stage MST via a drive system according to the measurement result of the interferometer system.

[0032] The projection optical system PL is supported by an optical platform 73 below (on the -Z side) the mask stage MST. The projection optical system PL is configured similarly to, for example, the projection optical system disclosed in U.S. Patent No. 5,729,331. The projection area of ​​the pattern image of the mask MSK includes, for example, a plurality (e.g., seven) of projection optical units 100 arranged in an alternating pattern, forming an image field with the Y-axis as its length direction. Here, four projection optical units 100 are arranged at predetermined intervals in the Y-axis direction, and the remaining three projection optical units 100 are separated from the four projection optical units 100 towards the +X side and arranged at predetermined intervals in the Y-axis direction. Each of the plurality of projection optical units 100 uses a configuration that forms an upright image using, for example, a telecentric system. It should be noted that the plurality of projection areas of the alternatingly arranged projection optical units 100 are collectively referred to as the exposure area.

[0033] When the illumination area on the mask MSK is illuminated by the illumination light IL from the illumination system IOP, a projected image (partially upright image) of the circuit pattern of the mask MSK within the illumination area is formed in the irradiation area (exposure area (conjugate with the illumination area)) on the substrate P using the illumination light IL that passes through the mask MSK via the projection optics system PL. The substrate P is positioned on the image plane side of the projection optics system PL. Here, a photoresist (sensor) is coated on the surface of the substrate P. By synchronously driving the mask stage MST and the substrate stage PST (i.e., driving the mask MSK relative to the illumination area (illumination light IL) in the scanning direction (X-axis direction)) and driving the substrate P relative to the exposure area (illumination light IL) in the same scanning direction, the substrate P is exposed, and the pattern of the mask MSK is transferred onto the substrate P.

[0034] The substrate stage PST is positioned on the anti-vibration device 81 below (on the -Z side) the projection optical system PL. The substrate P is held on the substrate stage PST by means of a substrate support (not shown).

[0035] The position information (including rotation information (deflection (θz rotation in the θz direction), pitch (θx rotation in the θx direction), and roll (θy rotation in the θy direction))) of the substrate stage PST in the XY plane is measured by an interferometer system. The interferometer system measures the position of the substrate stage PST by illuminating a measuring beam from the optical platform 73 onto a moving mirror (or a mirror-processed reflective surface (not shown)) located at the end of the substrate stage PST and receiving the reflected light from the moving mirror. This measurement result is supplied to the control device CNT, which drives the substrate stage PST according to the measurement result of the interferometer system.

[0036] In the exposure apparatus 10, alignment measurements (e.g., EGA) are performed before exposure, and the substrate P is exposed according to the following steps using the results. First, the mask stage MST and the substrate stage PST are synchronously driven in the X-axis direction according to the instructions of the control device CNT. This results in scanning exposure of the first exposure area on the substrate P. At the end of the scanning exposure of the first exposure area, the control device CNT moves the substrate stage PST to a position corresponding to the second exposure area (stepping). Then, the second exposure area is scanned. The control device CNT similarly repeats the stepping between exposure areas of the substrate P and the scanning exposure of the exposure areas, transferring the pattern of the mask MSK to all exposure areas on the substrate P.

[0037] (Composition of vibration damping device 81)

[0038] Next, the composition of the vibration damping device 81 will be explained. Figure 2 (A) is a top view of the vibration damping device 81 viewed from the +Z direction. Figure 2 (B) is a diagram of the vibration damping device 81 viewed from the -X direction. Figure 3 This is a diagram used to illustrate the structure of the vibration damping device 81.

[0039] like Figure 1 As shown, the vibration damping device 81 includes a base 81a and a base support device 810. The base support device 810 includes multiple pneumatic mounting seats 81b supporting the base 81a, multiple position sensors 82-1, 82-2, 82-3, 82-4, and a control device CNT. Figure 2 As shown in (A), in this embodiment, the base 81a has a rectangular shape when viewed from above, and the pneumatic mounting base 81b includes pneumatic mounting bases 81b-1, 81b-2, 81b-3, and 81b-4 disposed at the four corners of the base 81a.

[0040] The pneumatic mounting bases 81b-1 to 81b-4 each have a bellows, for example, made of synthetic rubber. One end of the bellows in the direction of expansion and contraction (in this case, the Z-axis direction) is mechanically connected to the lower surface of the base 81a, and the other end is disposed on the ground F. Figure 3 As shown, the air supply device 85 is connected to the bellows of the pneumatic mounting seats 81b-1 to 81b-4 via valves 83-1, 83-2, 83-3, and 83-4. By changing the opening degree of valves 83-1 to 83-4, the pressure inside the bellows of the pneumatic mounting seats 81b-1 to 81b-4 can be changed, thereby changing the thrust in the Z-axis direction generated by the pneumatic mounting seats 81b-1 to 81b-4.

[0041] In this embodiment, the pneumatic mounting bases 81b-1 to 81b-4 have a cylindrical shape with the Z-axis as the axial direction. Therefore, the centers of the regions where one end of the bellows of each of the pneumatic mounting bases 81b-1 to 81b-4 contacts the lower surface of the base 81a are respectively designated as support points SP1, SP2, SP3, and SP4. Alternatively, the regions where one end of the bellows of each of the pneumatic mounting bases 81b-1 to 81b-4 contacts the lower surface of the base 81a can also be designated as support points SP1 to SP4. Furthermore, points other than the centers in these regions can also be designated as support points SP1 to SP4.

[0042] Position sensors 82-1, 82-2, 82-3, and 82-4 are respectively installed at the support points SP1 to SP4 of each pneumatic mounting base 81b-1 to 81b-4. These sensors detect the position (sometimes called the Z-relative position) of each support point SP1 to SP4 with the ground F as the reference.

[0043] like Figure 3 As shown, the position detection signals output by position sensors 82-1 to 82-4 are input to the control device CNT. In addition, the control device CNT is also input with pressure detection signals, which are output by pressure sensors 84-1, 84-2, 84-3, and 84-4, which measure the pressure inside the bellows of the pneumatic mounting brackets 81b-1 to 81b-4, respectively.

[0044] The control device CNT controls the opening degrees of valves 83-1, 83-2, 83-3, and 83-4 based on position detection signals from position sensors 82-1 to 82-4 and pressure detection signals from pressure sensors 84-1 to 84-4, thereby controlling the thrust in the Z-axis direction generated by pneumatic mounting bases 81b-1 to 81b-4. This allows for control of the attitude of the base 81a, i.e., the attitude of the main body 70.

[0045] In the exposure apparatus 10, in addition to vibrations transmitted from the ground F, the orientation of the main body 70 also changes due to load movements associated with the movement of the substrate stage PST and the mask stage MST in the scanning direction. Therefore, typically, orientation control is performed in the exposure apparatus to bring the orientation of the main body 70 closer to a target orientation. Orientation control is performed, for example, when the substrate stage PST is moved relative to the projection optical system PL in the scanning direction.

[0046] Figure 4 This is a block diagram illustrating an example of the attitude control method for the main body 70. Figure 4 In the attitude control method shown, the main body 70 of the exposure device 10 is regarded as a rigid body.

[0047] exist Figure 4In the block diagram shown, a signal corresponding to the target posture of the main body 70 of the exposure apparatus 10 is supplied to the addition side of the subtraction unit 200. Additionally, signals corresponding to the Z-relative position measured by position sensors 82-1 to 82-4 are transformed into the Z-position, θx-position (rotation about the X-axis), and θy-position (rotation about the Y-axis) of the main body 70, and then supplied to the subtraction side of the subtraction unit 200. The Z-position, θx-position (rotation about the X-axis), and θy-position (rotation about the Y-axis) of the main body 70 are also supplied to the feedback (FB) control unit 202.

[0048] The output of the subtraction unit 200 is supplied to the PI control unit 201, which performs proportional and integral control. The outputs of the PI control unit 201 and the FB control unit 202 are supplied to the addition unit 203.

[0049] The output from the adder 203 (command values ​​for the Z position, θx position (rotation about the X-axis), and θy position (rotation about the Y-axis) of the main body 70) is converted into pressure (target pressure) for the four pneumatic mounting seats 81b-1 to 81b-4 to achieve the command value and supplied to the adder 206. Additionally, the output (pressure value) from the feedforward (FF) control unit 205, based on the positions of the substrate stage PST and the mask stage MST, is supplied to the adder 206.

[0050] The output and interference force from the adder 206 are supplied to the adder 207 to calculate the pressure command value for each of the four pneumatic mounting seats 81b-1 to 81b-4. The control device CNT adjusts the opening of valves 83-1 to 83-4 respectively so that the pressure of the pneumatic mounting seats 81b-1 to 81b-4 becomes the pressure command value.

[0051] The inventor discovered that during the process Figure 4 When the posture of the main body 70 is controlled, the stage 81a (main body 70) deforms due to the movement of the load associated with the movement of the substrate stage PST and the mask stage MST in the scanning direction.

[0052] Figure 5 (A) is shown in the passage Figure 4 The diagram shows the simulation results of the positions of support points SP1 to SP4 in the Z-axis direction (referred to as the first position) with the ground F as the reference, under the condition that the pressure of the pneumatic mounting bases 81b-1 to 81b-4 is controlled by the control method shown. Figure 5Figure (B) shows the results obtained by calculating the least squares plane of the lower surface of the base 81a (lower surface of the main body 70) based on the first position of each of the support points SP1 to SP4, and calculating the position (called the second position) of each point in the Z-axis direction with reference to the ground surface F (the mounting surface) at the least squares plane, where the axes extending along the Z-axis direction through the support points SP1 to SP4 intersect the least squares plane. In the case of calculating the points on the least squares plane projected along the Z-axis direction from the support points SP1 to SP4, the position of each point in the Z-axis direction with reference to the ground surface F (the mounting surface) at the least squares plane, where the axes extending along the Z-axis direction through the support points SP1 to SP4 intersect the least squares plane, can be said to be the calculated position of each point in the Z-axis direction with reference to the ground surface F.

[0053] in addition, Figure 5 (C) is a diagram showing the difference between the first and second positions of each of the support points SP1 to SP4. Figure 5 (A) ~ Figure 5 The horizontal axis of (C) represents time. It should be noted that, regarding position 1, since support points SP1 and SP4 exhibit approximately the same behavior, therefore, in Figure 5 In (A), a solid line (SP1, 4) represents the first position of support points SP1 and SP4. Since support points SP2 and SP3 exhibit approximately the same behavior, a dashed line (SP2, 3) represents the first position of support points SP2 and SP3. Furthermore, regarding the second position, since support points SP1 and SP4 exhibit approximately the same behavior, therefore... Figure 5 In (B), a solid line (SP1, 4) represents the second position of support points SP1 and SP4. Since support points SP2 and SP3 exhibit approximately the same behavior, a dashed line (SP2, 3) represents the second position of support points SP2 and SP3. Furthermore, regarding the difference between the first and second positions, since support points SP2 and SP4 exhibit approximately the same behavior, in... Figure 5 In (C), a solid line (SP2, 4) represents the difference between the first and second positions. Since support points SP1 and SP3 exhibit approximately the same behavior, a dashed line (SP1, 3) represents the first and second positions.

[0054] like Figure 5 As shown in (C), a difference arises between the Z-relative positions (first position) of support points SP1 to SP4 and the Z-relative positions (second position) of support points SP1 to SP4 in the least squares plane. This indicates that the base 81a (i.e., the main body 70) has deformed. This point will be explained.

[0055] Figure 6 This diagram illustrates the relationship between the Z-relative positions (position 1) of support points SP1 to SP4 and the Z-relative positions (position 2) of support points SP1 to SP4 in the least squares plane calculated from their Z-relative positions, using an orthogonal XYZ coordinate system. The Z-relative positions of support points SP1 to SP4 are represented by coordinates (X1, Y1, Za1), (X2, Y2, Za2), (X3, Y3, Za3), and (X4, Y4, Za4), respectively. Conversely, points on the least squares plane corresponding to support points SP1 to SP4 are designated as SP1' to SP4', and their positions are represented by coordinates (X1, Y1, Zls1), (X2, Y2, Zls2), (X3, Y3, Zls3), and (X4, Y4, Zls4), respectively.

[0056] according to Figure 5 (C), Za1 > Zls1, Za3 > Zls3, Za2 < Zls2, Za4 < Zls4. Therefore, as... Figure 6 As shown, the lower surface of the base 81a, i.e., the main body 70, is deformed relative to the least squares plane LSP, which is represented by the dashed line. The deformation of the main body 70 may degrade the exposure accuracy of the exposure apparatus 10.

[0057] Therefore, in this embodiment, the following is adopted: Figure 7 The block diagram shown illustrates a control method in which, in this control method, Figure 4 The control loop shown is the main loop (second control), and a minor loop (first control) that suppresses the deformation of the base plate 81a is inserted.

[0058] Figure 7 The portion of the block diagram shown, enclosed by a single-dot dash, is similar to... Figure 4 The block diagram shown is different, so this is the main point to explain.

[0059] exist Figure 7 In the block diagram shown, the positions (second positions) of the support points SP1 to SP4 in the least squares plane, respectively, based on the Z-relative positions (first positions) of the support points SP1 to SP4 detected by the position sensors 82-1 to 82-4 in the Z-axis direction with reference to the ground F, are supplied to the subtraction side of the subtraction unit 208, while the Z-relative positions (first positions) of the support points SP1 to SP4 detected by the position sensors 82-1 to 82-4 are supplied to the addition side.

[0060] Furthermore, the pressure of the pneumatic mounting bases 81b-1 to 81b-4 is controlled based on the difference (correction value) between the first and second positions of each of the support points SP1 to SP4. Specifically, the pressure of the pneumatic mounting bases 81b-1 to 81b-4 is controlled so that the Z-relative position (first position) of the support points SP1 to SP4 detected by the position sensors 82-1 to 82-4 is consistent with the position (second position) of the support points SP1 to SP4 in the Z-axis direction with the ground F as the reference in the least squares plane. This suppresses the deformation of the base 81a (main body 70).

[0061] The correction value used in the control of the pneumatic mounting brackets 81b-1 to 81b-4 is supplied to the subtraction side of the subtraction unit 210, and the output from the addition unit 206 is supplied to the addition side to calculate the pressure command value for each of the four pneumatic mounting brackets 81b-1 to 81b-4 in the main cycle.

[0062] The smaller loop executes with a period that is the same as or shorter than the main loop, based on the deformation time constant of the base 81a (body 70). Therefore, attitude control of the body 70 can be performed while reducing the deformation of the base 81a (body 70). In other words, in... Figure 7 In the control method shown, the deformation of the base 81a (body 70) can be suppressed by controlling the posture of the main body 70 through a small cycle. This improves the exposure accuracy of the exposure apparatus 10. It should be noted that in this embodiment, the object controlled by the small cycle is the static deformation of the base 81a (body 70), so the small cycle can also be executed with a longer period than the main cycle.

[0063] Figure 8 This demonstrates a simulation application. Figure 7 A graph showing the difference between the first and second positions under the control method shown. Figure 5 Comparison (C) shows that the difference between the first and second positions decreases. That is, it is confirmed that... Figure 7 The control method shown can maintain the attitude controllability of the main body 70 while reducing the deformation of the main body 70.

[0064] In having Figure 1 In the exposure apparatus 10 shown, the exposure device will be based on the one configured according to Figure 4 The control shown in the block diagram (comparative example control) calculates the difference (position difference) between the first and second positions of each support point SP1 to SP4 based on the output of position sensors 82-1 to 82-4, and is based on the following... Figure 7 The difference (position difference) between the first position and the second position of each support point SP1 to SP4 calculated from the output of the position sensors 82-1 to 82-4 during the control of the block diagram shown (control of this embodiment) was compared.

[0065] Figure 9 (A) is a graph showing the moving speed of the substrate stage PST relative to time. A positive moving speed indicates that the substrate stage PST is moving in the +X direction, and a negative moving speed indicates that the substrate stage PST is moving in the -X direction.

[0066] Figure 9 (B) is a graph showing the moving speed of the mask stage MST relative to time. A positive moving speed indicates that the mask stage MST is moving in the +X direction, and a negative moving speed indicates that the mask stage MST is moving in the -X direction.

[0067] Figure 9 (C) ~ Figure 9 (F) are comparisons based on the following: Figure 4 The control shown in the block diagram (comparative example control) calculates the difference (position difference) between the first and second positions of each support point SP1 to SP4 based on the output of position sensors 82-1 to 82-4, and is based on the following... Figure 7 The diagram shown is a graph of the difference (position difference) between the first and second positions of each support point SP1 to SP4 calculated from the output of the position sensors 82-1 to 82-4 during the control (control of this embodiment).

[0068] like Figure 9 (C) ~ Figure 9 As shown in (F), when the control of the implementation method was applied to any support point SP1 to SP4 throughout the entire time period, the positional difference was smaller compared to the case where the control of the comparative example was applied. In this way, the deformation of the base 81a (body 70) can be suppressed by the control of the implementation method, which has been confirmed not only in simulations but also in actual exposure apparatuses.

[0069] As detailed above, the base support device 810 of this embodiment includes: a plurality of pneumatic mounting seats 81b-1 to 81b-4, which are disposed on the ground F, and a plurality of support points SP1 to SP4 on the lower surface side of the base 81a respectively support the base 81a and generate thrust relative to the support points SP1 to SP4 in the support direction (Z-axis direction); and a plurality of position sensors 82-1 to 82-4, which detect the position (first position) of each of the plurality of support points SP1 to SP4 in the Z-axis direction with the ground F as a reference. In addition, the base support device 810 is equipped with a control device CNT, which calculates the least squares plane of the lower surface of the base 81a based on the first position detected by multiple position sensors 82-1 to 82-4, and calculates the position (second position) of each point in the Z-axis direction with reference to the ground F at the intersection of the axis extending along the Z-axis direction through the support points SP1 to SP4 and the least squares plane. Based on the difference between the second position and the first position of each support point SP1 to SP4, the multiple pneumatic mounting seats 81b-1 to 81b-4 are controlled.

[0070] Therefore, as Figure 8 and Figure 9 (C) ~ Figure 9 As shown in (F), deformation of the base 81a can be suppressed. In addition, in this embodiment, the positions (Z relative positions) of the support points SP1 to SP4 relative to the ground F in the Z-axis direction are detected, and the least squares plane is calculated using the Z relative positions. Therefore, even if the ground F is uneven or tilted, deformation of the lower surface of the base 81a relative to the ground F can be suppressed, and the plane can be maintained.

[0071] Furthermore, in this embodiment, the base 81a has a rectangular shape, and the pneumatic mounting seats 81b-1 to 81b-4 are located near the four corners of the base 81a. When the base 81a is supported at three points, its degrees of freedom of movement and control are consistent, making deformation difficult. However, with the increasing size of the exposure apparatus 10, the base 81a has also become larger, making it difficult to support it at three points. By supporting the base 81a at four points, even a large base 81a can be stably supported. On the other hand, when the base 81a is supported at four points, its degrees of freedom of control exceed its degrees of freedom of movement, potentially causing deformation of the base 81a (body 70). Therefore, as shown in this embodiment, the thrust generated by each of the multiple pneumatic mounting bases 81b-1 to 81b-4 is controlled based on the difference between the position (first position) of each support point SP1 to SP4 in the Z-axis direction relative to the ground F and the position (second position) of each support point SP1 to SP4 in the least squares plane of the lower surface of the base 81a calculated based on the first position in the Z-axis direction relative to the ground F. Thus, even when the base 81a is supported at four points, deformation of the base 81a can be suppressed. It should be noted that this control method is not limited to the case where the number of support points of the base 81a is four; it can also be applied when there are five or more support points.

[0072] Furthermore, in this embodiment, the control device CNT controls the thrust generated in the Z-axis direction by the multiple pneumatic mounting bases 81b-1 to 81b-4 relative to the support points SP1 to SP4, so as to reduce the difference between the second position and the first position of each support point SP1 to SP4. This can suppress the deformation of the base 81a.

[0073] Furthermore, in this embodiment, the control device CNT controls the thrust generated by each of the pneumatic mounting bases 81b-1 to 81b-4 based on the target attitude of the base 81a and the Z-axis positions (first positions) of the support points SP1 to SP4 detected by the position sensors 82-1 to 82-4. This allows the attitude of the base 81a to approach the target attitude.

[0074] Furthermore, in this embodiment, control is performed on the thrust generated by each of the multiple pneumatic mounting bases 81b-1 to 81b-4 based on the difference between the second and first positions of each of the support points SP1 to SP4. Figure 7 The cycle of the small loop (the first cycle) is used to control the thrust generated by each of the multiple pneumatic mounts 81b-1 to 81b-4 based on the target attitude and first position of the base 81a. Figure 7The cycle of the main loop (the second cycle) is the same as or shorter than the cycle of the main loop. Thus, the attitude of the base 81a (the main body 70) can be controlled while suppressing the deformation of the base 81a (the main body 70).

[0075] It should be noted that in the above embodiment, a pneumatic mounting base 81b is used as multiple actuators, but actuators other than pneumatic mounting bases can also be used. Additionally, a damper other than an air damper can be used as a passive mounting base.

[0076] Furthermore, in the above embodiment, the least-squares plane of the lower surface of the base 81a was calculated, but approximate planes other than the least-squares plane can also be calculated. For example, an approximate plane whose sum of distances in the Z-axis direction to all measurement points is minimized can also be calculated.

[0077] It should be noted that in the above embodiment, the Z relative positions of support points SP1 to SP4 are transformed into the Z position, θx position and θy position of the base 81a, but they can also be transformed into the Z position, θx position, θy position and torsional component.

[0078] Furthermore, in the above embodiment, the case where the exposure device 10 is a scanning stepper has been described, but it is not limited thereto. The exposure device 10 may also be a stationary exposure device such as a stepper, or a shrinking projection exposure device that combines exposure areas with exposure areas in a stepping stitching manner.

[0079] In addition, in the above embodiments, the vibration damping device 81 can also be applied to devices other than the exposure device 10.

[0080] The above embodiments are preferred embodiments of the present invention. However, they are not limited thereto, and various modifications can be made without departing from the spirit of the present invention.

[0081] Explanation of reference numerals in the attached figures

[0082] 10 Exposure Devices

[0083] 70 main bodies

[0084] 81 anti-vibration device

[0085] 81a abutment

[0086] 81b, 81b-1 to 81b-4 pneumatic mounting base

[0087] 82-1~82-4 Position Sensors

[0088] 73 Optical Platform

[0089] CNT control device

[0090] F ground

[0091] LSP Least Squares Plane

[0092] MST Mask Stage

[0093] PST substrate carrier

[0094] Support points SP1 to SP4.

Claims

1. A base support device, comprising: Multiple actuators are arranged on the mounting surface, and the base is supported by multiple support points on the lower surface side of the base, and a thrust is generated relative to the support points in the support direction. Multiple detection units detect the first position of each of the multiple support points relative to the setting surface in the support direction; as well as The control unit calculates an approximate plane of the lower surface of the base based on the first position detected by the plurality of detection units, and calculates the second position of each point in the support direction with reference to the setting surface at which the axis extending along the support direction through the support point intersects the approximate plane. The control unit controls the plurality of actuators based on the difference between the second position and the first position of each support point.

2. The base support device according to claim 1, wherein, The base has a rectangular shape. The plurality of actuators are located near the four corners of the base.

3. The base support device according to claim 2, wherein, The control unit controls the thrust generated by the multiple actuators relative to the support point in the support direction, so as to reduce the difference.

4. The base support device according to any one of claims 1 to 3, wherein, The plurality of actuators are pneumatic actuators.

5. The base support device according to claim 3, wherein, The control unit controls the thrust generated by each of the plurality of actuators based on the target attitude of the base and the first position detected by the detection unit.

6. The base support device according to claim 5, wherein, The first cycle is approximately the same as or shorter than the second cycle. In the first cycle, control is performed on the thrust generated by each of the plurality of actuators based on the difference. In the second cycle, control is performed on the thrust generated by each of the plurality of actuators based on the target attitude and the first position.

7. The base support device according to claim 1, wherein, The approximate plane is the least squares plane.

8. An exposure apparatus comprising: The base support device according to any one of claims 1 to 7; A mask stage that can hold and move the mask; as well as An optical platform that supports the mask stage is disposed on the base support device.

9. An exposure apparatus comprising: The base support device according to any one of claims 1 to 7 A stage, located on the base support, capable of holding the substrate and moving it in the scanning direction; and The projection optical system is located on the platform. When the control unit moves the stage relative to the projection optical system in the scanning direction, it performs the following processes: detects the first position; calculates the approximate plane; calculates the second position; and controls the thrust generated by each of the plurality of actuators based on the difference between the second position and the first position of each of the support points.

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