JP5151852B2 - Correction information creation method, exposure method, exposure apparatus, and device manufacturing method - Google Patents

Description

  The present invention relates to a correction information creation method, an exposure method and an exposure apparatus, and a device manufacturing method, and particularly used in a lithography process for manufacturing an electronic device (microdevice) such as a semiconductor element (integrated circuit, etc.) or a liquid crystal display element. Correction information generating method suitable for generating correction information for correcting a position measurement error of a moving body such as a wafer stage of an exposure apparatus, and scanning the moving body holding an object using the correction information to pattern an object The present invention relates to an exposure method, an exposure apparatus, and a device manufacturing method using the exposure method.

  Conventionally, in a lithography process for manufacturing electronic devices (microdevices) such as semiconductor elements (integrated circuits, etc.), liquid crystal display elements, etc., a step-and-repeat type projection exposure apparatus (so-called stepper) or a step-and-scan type Projection exposure apparatuses (so-called scanning steppers (also called scanners)) are mainly used.

  In this type of exposure apparatus, in order to transfer a reticle (or mask) pattern to a plurality of shot regions on a substrate such as a wafer or a glass plate (hereinafter collectively referred to as a wafer), a wafer stage that holds the wafer includes: For example, it is driven in a two-dimensional direction by a linear motor or the like. The position of the wafer stage is generally measured by using a laser interferometer having high stability over a long period of time.

  However, with the recent miniaturization of patterns due to high integration of semiconductor elements, higher precision wafer stage position control performance has been required. For this reason, short-term fluctuations in measured values due to air fluctuations caused by the temperature change and temperature gradient of the atmosphere on the beam path of the laser interferometer cannot be ignored. In view of this, the inventor has previously proposed an invention relating to an exposure apparatus that employs an encoder having a measurement resolution comparable to or higher than that of a laser interferometer and a surface position measurement sensor (for example, see Patent Document 1).

  In the encoder system and the surface position measurement system employed in the exposure apparatus described in Patent Document 1, a measurement beam (which is a reflection type diffraction grating) provided on a wafer stage is irradiated with a measurement beam, and the reflected light is irradiated with the measurement beam. By detecting, the displacement or the surface position of the measurement side surface (that is, the wafer stage) in the periodic direction of the diffraction grating is measured. Here, there is no distortion in all the grating lines of the reflection type diffraction grating constituting the measurement surface, and there is no unevenness on the surface which also serves as the reflection surface, and the pitch of the grating lines is completely uniform. Producing a diffraction grating is a real problem and very difficult. Therefore, in view of such points, the inventor previously created correction data for correcting measurement errors due to diffraction grating distortion, surface irregularities, pitch non-uniformity, etc., and using the correction data An invention for correcting the measurement result of the encoder system (and the surface position measurement system) has also been proposed previously (see, for example, Patent Document 2).

  However, even if such an operation method of the measurement system is adopted, it is difficult to achieve the measurement accuracy (and control accuracy) of the position of the wafer stage required for the next-generation exposure apparatus. Turned out.

International Publication No. 2007/097379 Pamphlet International Publication No. 2008/026739 Pamphlet

  The present invention has been made under the circumstances described above. From a first viewpoint, the present invention is a correction information creation method for creating correction information for correcting a position measurement error of a moving body moving within a predetermined plane. Using a plurality of heads provided on one of the moving body and the outside of the moving body, irradiating measurement light on a measurement surface provided on the other of the moving body and the outside of the moving body, Receiving light from the measurement surface, measuring first position information of the moving body, measuring second position information of the moving body using an interferometer system independent of the plurality of heads, Driving the moving body along a moving path including at least one straight section extending in a predetermined direction within the predetermined plane according to any of the first and second position information; and Small error due to measurement surface In addition, the first position information is corrected using first correction information prepared in advance in order to correct a part, and the first position information and the second position information are corrected to obtain the first position information. Creating second correction information for correcting at least a part of errors included in the first position information excluding a part of errors corrected using the correction information in association with the movement path. And a correction information creating method including;

  According to this, the first position information of the moving body is measured using a plurality of heads, the second position information of the moving body is measured using an interferometer system, and the first and second position information The moving body is driven along a moving path including at least one straight section extending in a predetermined direction within a predetermined plane according to either of them. Then, at least a part of an error caused by the measurement surface included in the first position information is corrected using the first correction information created in advance, and the corrected first position information and second position information are corrected. The second correction information is created from the difference in association with the movement route. The second correction information is information for correcting at least a part of errors (residual errors) included in the first position information excluding a part of errors corrected using the first correction information. Therefore, by using the second correction information, the first position information corrected using the first correction information is further corrected, and the moving body is driven with high accuracy based on the corrected position information. Is possible. In addition, since the second correction information is created in association with a movement route including at least one straight section, unlike the case where the second correction information is created for the entire movement range of the moving object, the second correction information is simple and short. Thus, the second correction information can be created.

  According to a second aspect of the present invention, the object is irradiated with an energy beam and a movable body that holds the object and is movable in a predetermined plane is driven in the scanning direction in the predetermined plane to An exposure method for forming a pattern on the other side of the moving body and the outside of the moving body using a plurality of heads provided on one side of the moving body and the outside of the moving body. The measurement surface is irradiated with measurement light, the light from the measurement surface is received, and the first position information of the movable body is measured, and the first position information and the measurement included in the first position information are measured. The moving body using first correction information created to correct at least a part of an error caused by a surface and second correction information created using the correction information creating method of the present invention. It is the exposure method including the process of driving.

  According to this, the first position information of the moving body is measured using the plurality of heads that irradiate the measurement surface with the measurement light and receive the light from the measurement surface, and the first and second position information First correction information created for correcting at least a part of errors caused by the measurement surface included in the first position information, and second correction created using the correction information creation method of the present invention The moving body is driven using the information. In this case, the first position information corrected using the first correction information is further corrected by extracting the correction amount corresponding to the position of the moving body from the second correction information and using the correction amount. Based on the corrected position information, the moving body can be driven with high accuracy.

  According to a third aspect of the present invention, by scanning exposure in which a movable body that holds an object and is movable in a predetermined plane is driven in a scanning direction in the predetermined plane while irradiating the object with an energy beam, An exposure method for forming a pattern on the object, wherein a plurality of heads provided on one of the moving body and the outside of the moving body are used, and the other of the moving body and the outside of the moving body is used. The measurement surface is irradiated with measurement light, and the light from the measurement surface is received to measure the first position information of the movable body, and is included in the first position information and the first position information. First correction information created to correct at least a part of the error caused by the measurement surface, and the first position information excluding a part of the error corrected using the first correction information Correct at least some of the errors contained in In order, the moving body is an exposure method comprising the step of driving the movable body using a second correction information prepared in association with the movement path including a constant velocity section is constant speed driving.

  According to this, the first position information of the moving body is measured using the plurality of heads that irradiate the measurement surface with the measurement light and receive the light from the measurement surface, and the first position information and the first position information The first correction information created to correct at least a part of the error caused by the measurement surface included in one position information, and the part of the error corrected using the first correction information are excluded. Second correction information second correction information created in association with a movement path including a constant speed section in which the moving body is driven at a constant speed in order to correct at least a part of the errors included in the first position information. Then, the moving body is driven using. Therefore, in a moving path including a constant speed section where the moving body is driven at a constant speed, it becomes possible to drive the moving body with high accuracy in, for example, a scanning exposure section, and as a result, formation of a pattern on a highly accurate object by the scanning exposure method. Is possible.

  From a fourth viewpoint, the present invention provides a step of forming a pattern on an object using the first or second exposure method of the present invention; a step of processing the object on which the pattern is formed; A device manufacturing method including:

  According to a fifth aspect of the present invention, there is provided an exposure apparatus for forming a pattern on an object by scanning exposure in which the object is irradiated with an energy beam and driven in the scanning direction within the predetermined plane. A movable body that holds the object and is movable within the predetermined plane; a plurality of heads provided on one of the movable body and the outside of the movable body, and using the plurality of heads, A position measurement system that measures the first position information of the moving body by irradiating the measuring surface provided on the other of the moving body and the outside of the moving body with the measurement light and receiving the light from the measuring surface. The first position information, the first correction information created to correct at least a part of the error caused by the measurement surface included in the first position information, and the first correction information. Included in the first position information excluding some errors corrected by using Second correction information created in association with a movement path including a constant speed section in which the moving object is driven at a constant speed in order to correct at least a part of the generated error. An exposure apparatus comprising: a drive system for driving;

  According to this, it creates in order to correct | amend at least one part of the error resulting from the 1st position information of the moving body measured by a position measurement system, and the measurement surface contained in 1st position information with a drive system. In order to correct at least a part of the error included in the first position information excluding the corrected first correction information and a part of the error corrected by using the first correction information, the moving body is The moving body is driven using the second correction information created in association with the moving path including the constant speed section that is driven at high speed. Therefore, in a moving path including a constant speed section where the moving body is driven at a constant speed, it becomes possible to drive the moving body with high accuracy in, for example, a scanning exposure section, and as a result, formation of a pattern on a highly accurate object by the scanning exposure method. Is possible.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 schematically shows a configuration of an exposure apparatus 100 according to an embodiment. The exposure apparatus 100 is a step-and-scan projection exposure apparatus, a so-called scanner. As will be described later, in the present embodiment, a projection optical system PL and a primary alignment system AL1 (see FIGS. 4 and 5, etc.) are provided. In the following, the direction parallel to the optical axis AX of the projection optical system PL is the Z-axis direction, and the direction parallel to the straight line connecting the optical axis AX and the detection center of the primary alignment system AL1 in the plane orthogonal to this is the Y-axis direction. The direction orthogonal to the Z axis and the Y axis is defined as the X axis direction, and the rotation (tilt) directions around the X axis, the Y axis, and the Z axis are defined as the θx, θy, and θz directions, respectively.

  The exposure apparatus 100 includes an illumination system 10, a reticle stage RST, a projection unit PU, a stage apparatus 50 having a wafer stage WST, a control system for these, and the like. In FIG. 1, wafer W is mounted on wafer stage WST.

  The illumination system 10 illuminates a slit-like illumination area IAR on the reticle R defined by a reticle blind (also called a masking system) with illumination light (exposure light) IL with a substantially uniform illuminance. The configuration of the illumination system 10 is disclosed in, for example, US Patent Application Publication No. 2003/025890. Here, as an example of the illumination light IL, ArF excimer laser light (wavelength 193 nm) is used.

  On reticle stage RST, reticle R having a circuit pattern or the like formed on its pattern surface (lower surface in FIG. 1) is fixed, for example, by vacuum suction. The reticle stage RST can be finely driven in the XY plane by a reticle stage drive system 11 (not shown in FIG. 1, refer to FIG. 7) including a linear motor, for example, and also in the scanning direction (left and right direction in FIG. 1). In the Y-axis direction) at a predetermined scanning speed.

  Position information (including rotation information in the θz direction) of reticle stage RST in the XY plane is formed on movable mirror 15 (or on the end face of reticle stage RST) by reticle laser interferometer (hereinafter referred to as “reticle interferometer”) 116. For example, with a resolution of about 0.25 nm. The measurement value of reticle interferometer 116 is sent to main controller 20 (not shown in FIG. 1, refer to FIG. 7).

  Projection unit PU is arranged below reticle stage RST in FIG. The projection unit PU includes a lens barrel 40 and a projection optical system PL held in the lens barrel 40. As projection optical system PL, for example, a refractive optical system including a plurality of optical elements (lens elements) arranged along optical axis AX parallel to the Z-axis direction is used. The projection optical system PL is, for example, both-side telecentric and has a predetermined projection magnification (for example, 1/4 times, 1/5 times, or 1/8 times). For this reason, when the illumination area IAR on the reticle R is illuminated by the illumination system 10, the illumination light that has passed through the reticle R arranged so that the first surface (object surface) and the pattern surface of the projection optical system PL substantially coincide with each other. Due to IL, a reduced image of the circuit pattern of the reticle R in the illumination area IAR (a reduced image of a part of the circuit pattern) passes through the projection optical system PL (projection unit PU), and the second surface of the projection optical system PL ( It is formed in an area (hereinafter also referred to as an exposure area) IA that is conjugated to the illumination area IAR on the wafer W, which is disposed on the image plane side and has a resist (sensitive agent) coated on the surface thereof. Then, by synchronous driving of reticle stage RST and wafer stage WST, reticle R is moved relative to illumination area IAR (illumination light IL) in the scanning direction (Y-axis direction) and exposure area IA (illumination light IL). By moving the wafer W relative to the scanning direction (Y-axis direction), scanning exposure of one shot area (partition area) on the wafer W is performed, and a reticle pattern is transferred to the shot area. . That is, in this embodiment, a pattern is generated on the wafer W by the illumination system 10, the reticle R, and the projection optical system PL, and the pattern is formed on the wafer W by exposure of the sensitive layer (resist layer) on the wafer W by the illumination light IL. Is formed.

  As shown in FIG. 1, stage device 50 drives wafer stage WST disposed on base board 12, measurement system 200 (see FIG. 7) for measuring positional information of wafer stage WST, and wafer stage WST. A stage drive system 124 (see FIG. 7) and the like are provided. As shown in FIG. 7, the measurement system 200 includes an interferometer system 118, an encoder system 150, a surface position measurement system 180, and the like.

  Wafer stage WST is supported above base board 12 by a non-contact bearing (not shown) such as an air bearing with a clearance of about several μm. Wafer stage WST can be driven with a predetermined stroke in the X-axis direction and the Y-axis direction by stage drive system 124 (see FIG. 7) including a linear motor and the like.

  Wafer stage WST includes a stage main body 91 and a wafer table WTB mounted on stage main body 91. The wafer table WTB and the stage main body 91 are directed to the base board 12 in directions of six degrees of freedom (X, Y, Z, θx, etc.) by a drive system including a linear motor and a Z / leveling mechanism (including a voice coil motor). It can be driven to θy, θz).

  At the center of the upper surface of wafer table WTB, a wafer holder (not shown) for holding wafer W by vacuum suction or the like is provided. As shown in FIG. 2, a measurement plate 30 is provided on the + Y side of the wafer holder (wafer W) on the upper surface of wafer table WTB. The measurement plate 30 is provided with a reference mark FM at the center, and a pair of aerial image measurement slit patterns (slit-shaped measurement patterns) SL are provided on both sides of the reference mark FM in the X-axis direction. In correspondence with each aerial image measurement slit pattern SL, an optical system, a light receiving element, and the like are arranged inside wafer table WTB. That is, a pair of aerial image measurement devices 45A and 45B (see FIG. 7) including the aerial image measurement slit pattern SL is provided on wafer table WTB.

In addition, a scale used in an encoder system described later is formed on the upper surface of wafer table WTB. More specifically, Y scales 39Y ₁ and 39Y ₂ are formed in regions on one side and the other side of the upper surface of wafer table WTB in the X-axis direction (left and right direction in FIG. 2). The Y scales 39Y ₁ and 39Y ₂ are, for example, reflective type gratings (for example, diffraction gratings) in which the Y axis direction is a periodic direction in which grid lines 38 having the X axis direction as the longitudinal direction are arranged at a predetermined pitch in the Y axis direction. ).

Similarly, X scale 39X ₁ , X scale 39X ₁ , and Y scale 39Y ₁ and 39Y ₂ are sandwiched between one side and the other side in the Y-axis direction (up and down direction in the drawing in FIG. 2) of wafer table WTB. 39X ₂ are formed respectively. The X scales 39X ₁ and 39X ₂ are, for example, reflection type gratings (for example, diffraction gratings) in which the X-axis direction is a periodic direction in which grid lines 37 having a longitudinal direction in the Y-axis direction are arranged in the X-axis direction at a predetermined pitch. ).

  The pitch of the grid lines 37 and 38 is set to 1 μm, for example. In FIG. 2 and other figures, the pitch of the grating is shown larger than the actual pitch for convenience of illustration.

  It is also effective to cover the diffraction grating with a glass plate having a low coefficient of thermal expansion. Here, as the glass plate, a glass plate having the same thickness as that of the wafer, for example, a thickness of 1 mm can be used, and the surface of the glass plate is the same height (same surface) as the wafer surface. Installed on top of table WST.

  Further, as shown in FIG. 2, a reflecting surface 17a and a reflecting surface 17b used in an interferometer system to be described later are formed on the −Y end surface and the −X end surface of the wafer table WTB.

  Further, as shown in FIG. 2, a fiducial bar extending in the X-axis direction (hereinafter referred to as the CD bar disclosed in International Publication No. 2007/097379) is formed on the + Y side surface of wafer table WTB. 46, abbreviated as "FD bar"). Reference gratings (for example, diffraction gratings) 52 having a periodic direction in the Y-axis direction are formed in the vicinity of one end and the other end in the longitudinal direction of the FD bar 46 in a symmetrical arrangement with respect to the center line LL. . A plurality of reference marks M are formed on the upper surface of the FD bar 46. As each reference mark M, a two-dimensional mark having a size detectable by an alignment system described later is used.

In the exposure apparatus 100 of the present embodiment, as shown in FIGS. 4 and 5, a straight line (hereinafter referred to as a reference axis) parallel to the Y axis connecting the optical axis AX of the projection optical system PL and the detection center of the primary alignment system AL1. A primary alignment system AL1 having a detection center is arranged at a position on the LV at a predetermined distance from the optical axis AX to the -Y side. Primary alignment system AL1 is fixed to the lower surface of the main frame (not shown). As shown in FIG. 5, secondary alignment systems AL2 ₁ and AL2 _{2 in} which detection centers are arranged almost symmetrically with respect to the reference axis LV on one side and the other side in the X-axis direction across the primary alignment system AL1. , AL2 ₃ and AL2 ₄ are provided. The secondary alignment systems AL2 _{1 to} AL2 ₄ are fixed to the lower surface of the main frame (not shown) via a movable support member, and the drive mechanisms 60 _{1 to} 60 ₄ (see FIG. 7) are used for the X-axis direction. The relative positions of these detection areas can be adjusted.

In the present embodiment, for example, an image processing type FIA (Field Image Alignment) system is used as each of the alignment systems AL1, AL2 _{1 to} AL2 ₄ . Imaging signals from each of the alignment systems AL1, AL2 _{1 to} AL2 ₄ are supplied to the main controller 20 via a signal processing system (not shown).

As shown in FIG. 3, interferometer system 118 irradiates reflecting surface 17a or 17b with an interferometer beam (length measuring beam), receives the reflected light, and positions wafer stage WST in the XY plane. Y interferometer 16, three X interferometers 126 to 128, and a pair of Z interferometers 43A and 43B. More specifically, the Y interferometer 16 reflects at least three length measuring beams parallel to the Y axis including a pair of length measuring beams B4 ₁ and B4 ₂ symmetric with respect to the reference axis LV, and a movable mirror 41 described later. Irradiate. Further, as shown in FIG. 3, the X interferometer 126 includes a pair of length measuring beams symmetrical with respect to a straight line (hereinafter referred to as a reference axis) LH parallel to the X axis orthogonal to the optical axis AX and the reference axis LV. B5 _1, B5 parallel measurement beam into at least three X-axis including ₂ irradiates the reflecting surface 17b. Further, the X interferometer 127 includes at least a length measuring beam B6 having a length measuring axis as a straight line LA (hereinafter referred to as a reference axis) LA parallel to the X axis orthogonal to the reference axis LV at the detection center of the alignment system AL1. A measuring beam parallel to the two Y axes is irradiated onto the reflecting surface 17b. Further, the X interferometer 128 irradiates the reflection surface 17b with a measurement beam B7 parallel to the Y axis.

  Position information from each interferometer of the interferometer system 118 is supplied to the main controller 20. Based on the measurement results of Y interferometer 16 and X interferometer 126 or 127, main controller 20 rotates in the θx direction (ie, pitching), θy in addition to the X and Y positions of wafer table WTB (wafer stage WST). Directional rotation (ie rolling) and θz direction rotation (ie yawing) can also be calculated.

  As shown in FIG. 1, a movable mirror 41 having a concave reflecting surface is attached to the side surface on the −Y side of the stage main body 91. As can be seen from FIG. 2, the movable mirror 41 is longer in the X-axis direction than the reflecting surface 17a of the wafer table WTB.

  A pair of Z interferometers 43A and 43B that constitute part of the interferometer system 118 (see FIG. 7) are provided facing the movable mirror 41 (see FIGS. 1 and 3). The Z interferometers 43A and 43B respectively irradiate the movable mirror 41 with two measurement beams B1 and B2 parallel to the Y axis, and each of the measurement beams B1 and B2 through the movable mirror 41, for example, a projection unit The fixed mirrors 47A and 47B fixed to a frame (not shown) that supports the PU are irradiated. And each reflected light is received and the optical path length of length measuring beam B1, B2 is measured. Based on the result, main controller 20 calculates the position of wafer stage WST in the four degrees of freedom (Y, Z, θy, θz) direction.

  In the exposure apparatus 100 of the present embodiment, a plurality of encoder systems 150 are configured to measure the position (X, Y, θz) in the XY plane of the wafer stage WST independently of the interferometer system 118. A head unit is provided.

As shown in FIG. 4, four head units 62A, 62B, 62C, and 62D are arranged on the + X side, + Y side, -X side of the projection unit PU, and -Y side of the primary alignment system AL1, respectively. ing. Head units 62E and 62F are provided on both outer sides in the X-axis direction of the alignment systems AL1, AL2 _{1 to} AL2 ₄ , respectively. The head units 62A to 62F are fixed in a suspended state to a main frame (not shown) that holds the projection unit PU via support members. In FIG. 4, symbol UP indicates an unloading position at which a wafer on wafer stage WST is unloaded, and symbol LP indicates a loading position at which a new wafer is loaded on wafer stage WST. Show.

As shown in FIG. 5, the head units 62 </ b> A and 62 </ b> C include a plurality (here, five) of Y heads 65 _{1 to} 65 ₅ and Y heads 64 ₁ to 64 arranged at the interval WD on the reference axis LH. ₅ is provided. Hereinafter, Y heads 65 _{1 to} 65 ₅ and Y heads 64 ₁ to 64 ₅ are also referred to as Y head 65 and Y head 64, respectively, as necessary.

The head units 62A and 62C use the Y scales 39Y ₁ and 39Y ₂ to measure the position (Y position) of the wafer stage WST (wafer table WTB) in the Y-axis direction (multi-lens Y linear encoders 70A and 70C). 7). In the following, the Y linear encoder is abbreviated as “Y encoder” or “encoder” as appropriate.

As shown in FIG. 5, the head unit 62B is arranged on the + Y side of the projection unit PU, and includes a plurality of (here, four) X heads 66 _{5 to} 66 ₈ arranged on the reference axis LV at intervals WD. I have. Further, head unit 62D is arranged on the -Y side of primary alignment system AL1, a plurality which are arranged at a distance WD on reference axis LV (four in this case) and a X heads 66 ₁ to 66 _4. Hereinafter, the X heads 66 _{5 to} 66 ₈ and the X heads 66 _{1 to} 66 ₄ are also referred to as the X head 66 as necessary.

The head units 62B and 62D use X scales 39X ₁ and 39X ₂ to measure the position (X position) of the wafer stage WST (wafer table WTB) in the X-axis direction (X position). 7). In the following, the X linear encoder is abbreviated as “X encoder” or “encoder” as appropriate.

Here, the interval WD in the X-axis direction of the five Y heads 65 and 64 (more precisely, the irradiation points on the scale of the measurement beam emitted by the Y heads 65 and 64) provided in the head units 62A and 62C, respectively. At the time of exposure or the like, it is determined that at least one head always faces the corresponding Y scales 39Y ₁ and 39Y ₂ (irradiates the measurement beam). Similarly, the interval WD in the Y-axis direction between adjacent X heads 66 (more precisely, the irradiation points on the scale of the measurement beam emitted by the X head 66) provided in the head units 62B and 62D is determined during exposure. , It is determined that at least one head always faces the corresponding X scale 39X ₁ or 39X ₂ (irradiates the measurement beam). Therefore, in one state during the exposure operation shown for example in FIG. 8 (A), the Y head ₆₅ 3, 64 ₃ each Y scales 39Y _1, 39Y _2, X head 66 ₅ facing X scale 39X ₁ Yes (irradiating measurement beam).

The distance between the most + Y side X heads 66 ₄ of the most -Y side of the X heads 66 ₅ and the head unit 62D of the head unit 62B is the movement of the Y-axis direction of wafer stage WST, between the two X heads The width of the wafer table WTB is set to be narrower than the width in the Y-axis direction so that it can be switched (connected).

Head unit 62E, as shown in FIG. 5, a Y heads _67i to 674 ₄ of the plurality of (four in this case).

Head unit 62F is equipped with a Y heads 68 ₁ to 68 ₄ of a plurality (four in this case). Y heads 68 ₁ to 68 _4, with respect to the reference axis LV, is disposed on the Y head 67 _{4-67 1} and symmetrical position. Hereinafter, if necessary, the Y head 67 _{4-67 1} and Y heads 68 ₁ to 68 _4, each describing both Y heads 67 and Y heads 68.

At the time of alignment measurement, at least one Y head 67 and 68 faces the Y scales 39Y ₂ and 39Y ₁ , respectively. For example, in one state of alignment during measurement shown in FIG. 8 (B), Y head ₆₇ 3, 68 ₂ faces the Y scales 39Y _2, 39Y ₁ respectively. Y position (and θz rotation) of wafer stage WST is measured by Y heads 67 and 68 (that is, Y encoders 70E and 70F (see FIG. 7) configured by Y heads 67 and 68).

In the present embodiment, the Y heads 67 ₃ and 68 ₂ adjacent to the secondary alignment systems AL2 ₁ and AL2 ₄ in the X-axis direction are used as a pair of reference grids of the FD bar 46 when measuring the baseline of the secondary alignment system. The Y position of the FD bar 46 is measured at the position of each reference grating 52 by the Y heads 67 ₃ and 68 ₂ that face each other and the pair of reference gratings 52. Hereinafter, encoders configured by Y heads 67 ₃ and 68 ₂ respectively facing the pair of reference gratings 52 are referred to as Y linear encoders 70E ₂ and 70F ₂ . For identification, the Y encoder constituted by the Y heads 67 and 68 facing the Y scales 39Y ₂ and 39Y ₁ is referred to as Y encoders 70E ₁ and 70F ₁ .

  Here, as each encoder head (Y head, X head), for example, an interference type encoder head disclosed in International Publication No. 2007/097379 pamphlet can be used. In this type of encoder head, two measurement beams are irradiated onto corresponding scales, the respective return lights are combined into one interference light, and the intensity of the interference light is measured using a photodetector. Based on the intensity change of the interference light, the displacement in the measurement direction of the scale (period direction of the diffraction grating) is measured.

The measured values of the encoders 70A to 70F described above are supplied to the main controller 20. Main controller 20 determines position (X) of wafer stage WST in the XY plane based on the measurement values of three of encoders 70A to 70D or three of encoders 70E ₁ , 70F ₁ , 70B and 70D. , Y, θz). Main controller 20 controls the rotation of FD bar 46 (wafer stage WST) in the θz direction based on the measurement values of linear encoders 70E ₂ and 70F ₂ . A method for calculating the position of wafer stage WST based on the measurement values of encoders 70A to 70F will be described later.

  Furthermore, in the exposure apparatus 100 of the present embodiment, as shown in FIGS. 4 and 6, a multipoint focal position detection system (hereinafter referred to as “multipoint AF system”) including an irradiation system 90a and a light receiving system 90b. ) Is provided. As the multipoint AF system, an oblique incidence system having the same configuration as that disclosed in, for example, US Pat. No. 5,448,332 is adopted. In the present embodiment, as an example, the irradiation system 90a is disposed on the + Y side of the −X end portion of the head unit 62E described above, and light is received on the + Y side of the + X end portion of the head unit 62F while facing this. A system 90b is arranged. The multipoint AF system (90a, 90b) is fixed to the lower surface of the main frame that holds the projection unit PU.

  In FIG. 4 and FIG. 6, a plurality of detection points irradiated with the detection beam are not shown individually, but as elongated detection areas (beam areas) AF extending in the X-axis direction between the irradiation system 90a and the light receiving system 90b. It is shown. Since the detection area AF is set to have a length in the X-axis direction that is approximately the same as the diameter of the wafer W, the wafer W is scanned almost in the Y-axis direction once in the Z-axis direction. Position information (surface position information) can be measured.

  As shown in FIG. 6, each pair of pairs constituting a part of the surface position measurement system 180 is arranged in the vicinity of both ends of the detection area AF of the multipoint AF system (90a, 90b) in a symmetrical arrangement with respect to the reference axis LV. Heads for Z position measurement (hereinafter abbreviated as “Z head”) 72a, 72b and 72c, 72d are provided. These Z heads 72a to 72d are fixed to the lower surface of a main frame (not shown).

As the Z heads 72a to 72d, for example, a head of an optical displacement sensor similar to an optical pickup used in a CD drive device or the like is used. Z heads 72a to 72d irradiate wafer table WTB with a measurement beam from above, receive the reflected light, and measure the surface position of wafer table WTB at the irradiation point. In the present embodiment, a configuration is adopted in which the measurement beam of the Z head is reflected by the surfaces of the reflective diffraction gratings constituting the Y scales 39Y ₁ and 39Y ₂ described above.

Further, as shown in FIG. 6, the head units 62A and 62C described above are in the same X position as the five Y heads 65 _j and 64 _i (i, j = 1 to 5) provided in the head units 62A and 62C. The five Z heads 76 _j and 74 _i (i, j = 1 to 5) are provided while being shifted. The five Z heads 76 _j and 74 _i belonging to the head units 62A and 62C are arranged symmetrically with respect to the reference axis LV. Incidentally, as each Z head 76 _j, 74 _i, the head of the same optical displacement sensor as described above for Z head 72a~72d is employed.

Above Z heads 72a to 72d, 74 to _72d, 76 ₁ to 76 _5, as shown in FIG. 7, are connected to the main controller 20 via the signal processing and selection device 170, the main control device 20, Z head 72a~72d via signal processing and selection device 170, and 74 to _72d, 76 ₁ to 76 operating condition by selecting any Z head from _five, and its operating state Surface position information detected by the Z head is received via the signal processing / selection device 170. In this embodiment, Z head _{72a~72d, 74 1 ~74 5, 76} 1 ~76 5 and the position information of the tilt direction and a signal processing and selection device 170 with respect to the Z-axis direction and the XY plane of wafer stage WST A surface position measurement system 180 is measured.

  In the present embodiment, main controller 20 uses surface position measurement system 180 (see FIG. 7), in an effective stroke area of wafer stage WST, that is, in an area where wafer stage WST moves for exposure and alignment measurement. The position coordinates in the two-degree-of-freedom direction (Z, θy) are measured. A method for calculating the position of wafer stage WST based on the measurement values of surface position measurement system 180 will be described later.

  FIG. 7 shows the main configuration of the control system of the exposure apparatus 100. This control system is mainly configured of a main control device 20 composed of a microcomputer (or a workstation) for overall control of the entire apparatus.

In the exposure apparatus 100 of the present embodiment configured as described above, the unloading position UP (see FIG. 4) is performed according to a procedure similar to the procedure disclosed in the embodiment of the pamphlet of International Publication No. 2007/097379, for example. ), Unloading the wafer W at the loading position LP (see FIG. 4), loading the new wafer W onto the wafer table WTB, and primary alignment using the reference mark FM of the measurement plate 30 and the primary alignment system AL1. Processing of the first half of baseline check of the system AL1, resetting (resetting) the origin of the encoder system and interferometer system, alignment measurement of the wafer W using the alignment systems AL1, AL2 _{1 to} AL2 ₄ , focus mapping in parallel with this, Aerial image measuring instruments 45A and 45B In the step-and-scan method based on the position information of each shot area on the wafer obtained as a result of the alignment check and the latter half of the baseline check of the primary alignment system AL1 A series of processing using wafer stage WST such as exposure of a plurality of shot areas on wafer W is executed by main controller 20. Detailed description is omitted.

In addition, the baseline measurement of the secondary alignment systems AL2 _{1 to} AL2 ₄ is performed at the appropriate timing with the measurement values of the encoders 70E ₂ and 70F ₂ described above, as in the method disclosed in International Publication No. 2007/097379. Based on the adjustment of the θz rotation of the FD bar 46 (wafer stage WST), the reference marks M on the FD bar 46 in the respective fields of view are simultaneously measured using the alignment systems AL1, AL2 _{1 to} AL2 _4. It is done by doing.

In the present embodiment, as described above, the main controller 20 includes three of the encoders 70A to 70D (that is, the X head 66 and the Y heads 65 and 64), or the encoders 70E ₁ , 7F ₁ , 70B, and 70D. The position (X, Y, θz) in the XY plane of wafer stage WST is calculated based on the measured values of three of them (that is, X head 66, Y head 68, 67). Here, the measured values of X head 66 and Y heads 65 and 64 (or 68 and 67) (represented as C _X , C _Y1 and C _Y2 , respectively) are at the position (X, Y, θz) of wafer stage WST. On the other hand, it depends on the following.

C _X = (p _X −X) cos θz + (q _X −Y) sin θz (1a)
C _Y1 = − (p _Y1 −X) sin θz + (q _Y1 −Y) cos θz (1b)
C _Y2 = − (p _Y2 −X) sin θz + (q _Y2 −Y) cos θz (1c)
However, (p _X , q _X ), (p _{Y 1} , q _{Y 1} ), (p _{Y 2} , q _{Y 2} ) are X, 66, Y (or 68), and Y (or 67) X, 66, respectively. This is the Y installation position (more precisely, the X and Y positions of the irradiation point of the measurement beam). Therefore, main controller 20 substitutes the measured values C _X , C _Y1 , and C _Y2 of the three heads into simultaneous equations (1a) to (1c) and solves them to obtain the values in the XY plane of wafer stage WST. The position (X, Y, θz) is calculated. Main controller 20 drives and controls wafer stage WST according to the calculation result.

Main controller 20 controls the rotation of FD bar 46 (wafer stage WST) in the θz direction based on the measurement values of linear encoders 70E ₂ and 70F ₂ . Here, the measured values of the linear encoders 70E ₂ and 70F ₂ (represented as C _Y1 and _CY2 respectively) are expressed by the equations (1b) and (1c) with respect to the (X, Y, θz) position of the FD bar 46. Depends on. Therefore, the θz position of the FD bar 46 is obtained from the measured values C _Y1 and C _Y2 as follows.

sin θz = − (C _Y1 −C _Y2 ) / (p _Y1 −p _Y2 ) (2)
However, for the sake of simplicity, q _Y1 = q _Y2 is assumed.

  In the present embodiment, main controller 20 uses surface position measurement system 180 in the effective stroke area of wafer stage WST, that is, in the area where wafer stage WST moves for exposure and alignment measurement. The position coordinates in the degree direction (Z, θy) are measured.

More specifically, the main controller 20, during exposure, at least each one of Z heads _{76 j, 74 i (j,} i is any of 1 to 5) using the measurement values of, on the upper surface of wafer table WTB reference point in (upper surface and the intersection between the optical axis AX of wafer table WTB), and calculates the height _{Z 0} and rolling θy of the wafer stage WST. In one state during the exposure operation shown in FIG. 8A, the measured values of the Z heads 76 ₃ and 74 ₃ facing the Y scales 39Y ₁ and 39Y ₂ are used. Here, the measured values (represented as Z ₁ and Z ₂ respectively) of the Z heads 76 _j and 74 _i (j and i are any one of 1 to 5) are (Z ₀ , θx, θy) of the wafer stage WST. It depends on the position as follows.

Z ₁ = −tan θy · p ₁ + tan θx · q ₁ + Z ₀ (3a)
Z ₂ = −tan θy · p ₂ + tan θx · q ₂ + Z ₀ (3b)
However, the upper surface of wafer table WTB including the scale surface is assumed to be an ideal plane. (P ₁ , q ₁ ) and (p ₂ , q ₂ ) are the X and Y installation positions of the Z heads 76 _j and 74 _i (more precisely, the X and Y positions of the irradiation point of the measurement beam), respectively. is there. From the equations (3a) and (3b), the following equations (4a) and (4b) are derived.

Z ₀ = [Z ₁ + Z ₂ −tan θx · (q ₁ + q ₂ )] / 2 (4a)
tan θy = [Z ₁ −Z ₂ −tan θx · (q ₁ −q ₂ )] / (p ₁ −p ₂ ) (4b)
Therefore, main controller 20 calculates height Z ₀ of wafer stage WST and rolling θy from equations (4a) and (4b) using measured values Z ₁ and Z ₂ of Z heads 76 _j and 74 _i. To do. However, the pitching θx uses a measurement result of another sensor system (interferometer system 118 in the present embodiment).

At the time of focus calibration and focus mapping shown in FIG. 9, main controller 20 expresses measured values of four Z heads 72a to 72d facing Y scales 39Y ₁ and 39Y ₂ (represented as Za, Zb, Zc, and Zd, respectively). The height Z ₀ and rolling θy of the wafer table WTB at the center (X, Y) = (Ox ′, Oy ′) of the plurality of detection points of the multipoint AF system (90a, 90b) are Calculate as follows.

Z ₀ = (Za + Zb + Zc + Zd) / 4 (5a)
tanθy = - (Za + Zb- Zc-Zd) / (p a + p b -p c -p d) ... (5b)
Here, (p _a , q _a ), (p _b , q _b ), (p _c , q _c ), and (p _d , q _d ) are the X and Y installation positions (more accurate) of the Z heads 72a to 72d, respectively. (X, Y position of the irradiation point of the measurement beam). _{However, p a = p b, p} c = p d, q a = q c, q b = q d, (p a + p c) / 2 = (p b + p d) / 2 = Ox ', (q a + Q _b ) / 2 = (q _c + q _d ) / 2 = Oy ′. As in the previous case, the pitching θx uses the measurement result of another sensor system (interferometer system 118 in the present embodiment).

  Next, an operation method of the encoder system 150 and the surface position measurement system 180 in the exposure apparatus of this embodiment will be described.

As described above, the encoder heads (hereinafter also referred to as heads appropriately) 64 to 68 constituting the encoder system 150 of the present embodiment have a target beam (Y scale 39Y ₁ , YB) provided with a measurement beam on the wafer table WTB. XY plane of wafer table WTB (wafer stage WST) by irradiating 39Y ₂ and any _{one of} X scales 39X ₁ and 39X ₂ ) and receiving a diffracted beam generated from a reflective diffraction grating constituting the target scale. The position information in is measured. Further, Z heads 72a~72d constituting the surface position measurement system 180, _72d, 76 ₁ to 76 _5, similarly to the encoder head, to be measured the measuring beam in the Y scales 39Y ₁ or 39Y ₂ By irradiating and receiving the reflected beam, position information (Z position information) in the Z-axis direction of wafer stage WST, that is, surface position information (Z position information) on the upper surface of wafer table WTB is measured.

As described above, the reflective diffraction gratings constituting the scales 39Y ₁ , 39Y ₂ , 39X ₁ , 39X ₂ are arranged at a predetermined pitch (for example, 1 μm as described above) along the Y-axis direction or the X-axis direction. In addition, the surface of the reflection type diffraction grating also serves as a reflection surface which is a measurement surface of the Z head. However, to produce (form) an ideal reflective diffraction grating in which all the grating lines are not distorted, the surface that also serves as the reflecting surface has no irregularities, and the pitch of the grating lines is completely uniform. In fact, it is very difficult. Even if an ideal diffraction grating can be manufactured, the diffraction grating is deformed or the pitch of the grating changes due to thermal expansion or other causes over time. Further, the thickness of the cover glass provided for protecting the diffraction grating is not necessarily uniform. Therefore, in the exposure apparatus 100 of the present embodiment, before the main controller 20 performs a normal operation (a series of operations for performing wafer exposure), distortion of the diffraction grating, unevenness of the surface, and Correction data for correcting measurement errors caused by the non-uniformity of the grating pitch and the non-uniformity of the cover glass thickness is created. While the exposure apparatus 100 is in operation, the main controller 20 always corrects the measurement results of the encoder system 150 and the surface position measurement system 180 using the correction data. Thereby, the measurement accuracy of both systems 150 and 180 is guaranteed.

  In the present embodiment, the first correction data for correcting the measurement error (low-order component of the measurement error) that can vary with time in both systems 150 and 180 due to the scale (and the measurement surface), and the first correction data. The second correction data for correcting the measurement error (high-order component of the measurement error) that cannot be corrected even when using, and hardly fluctuates with time, is used.

Here, as an example, the measurement error of the encoder system 150 caused by diffraction grating distortion (including non-uniform pitch), and the surface position measurement system 180 caused by irregularities on the surface (reflection surface) of the diffraction grating. Taking the measurement error, the procedure for creating the first correction data will be described. When creating correction data for these measurement errors, the main controller 20 uses, as an example, Y heads 65 ₃ , 64 ₃ and Z heads 76 ₃ , 74 ₃ for the diffraction gratings of the Y scales 39Y ₁ , 39Y ₂ . The distortion and the irregularities on the surface of the diffraction grating are measured (see FIG. 10).

Specifically, it is as follows.
a. Main controller 20 uses interferometer system 118 to monitor position information of wafer stage WST, and uses stage drive system 124 to place wafer stage WST (wafer table WTB) in a reference posture (predetermined Z position Z _0). And θx ₀ = θy ₀ = θz ₀ = 0).
b. Next, main controller 20 drives wafer stage WST in the XY plane to move Y heads 65 ₃ and 64 ₃ and Z heads 76 ₃ and 74 ₃ to one end in the longitudinal direction of Y scales 39Y ₁ and 39Y _2. Part, for example, the -Y end part. In this case, since each of the Y heads 65 ₃ and 64 ₃ and the Z heads 76 ₃ and 74 ₃ are arranged at the same position in the X-axis direction, normally (except in special cases), the Y heads 65 ₃ and 64 _{3 3 is} merely opposed to the Y scales 39Y ₁ and 39Y ₂ , and the Z heads 76 ₃ and 74 ₃ are also simultaneously opposed to the Y scales 39Y ₁ and 39Y ₂ , respectively. In FIG. 10, the Y head 65 ₃ and the Z head 76 ₃ (irradiation point of the measurement beam) are irradiated to the x position x ₁₃ on the Y scale 39Y ₁ , and the Y head 64 ₃ and the Z head 74 ₃ (irradiation of the measurement beam). point) is the Y scales 39Y ₂ on the x position _{x 22,} and the state of being positioned, respectively are shown.

c. Next, main controller 20 controls stage drive system 124 according to the measurement result of interferometer system 118, and keeps wafer stage WST (wafer table WTB) in one direction in the Y-axis direction while maintaining the reference posture. For example, it is moved in the -Y direction (the direction of the white arrow in FIG. 10). Then, every time wafer stage WST moves a predetermined distance in the −Y direction, main controller 20 uses Y heads 65 ₃ and 64 _3, and Y positions Y ₁ and Y of Y scales 39Y ₁ and 39Y ₂ , respectively. _2, with the Z head _{763, 743,} respectively, the Y scales 39Y _1, the surface position of 39Y ₂ (Z-axis direction position) Z _1, Z ₂ at the irradiation point of measurement beams is measured.
d. Further, main controller 20 predicts the measurement values (Y ₁ , Y ₂ , Z ₁ , Z ₂ ) of each head using the measurement result of interferometer system 118. In the following, it is assumed that the predicted measurement values (predicted values) are expressed as Y ₁ ′, Y ₂ ′, Z ₁ ′, and Z ₂ ′, respectively.

Then, main controller 20 determines the distortion ΔY ₁ (y) = Y ₁ ′ −Y ₁ , ΔY ₂ (y) = y of Y scales 39Y ₁ and 39Y ₂ from the difference between the measured value of the Y head and the corresponding predicted value. Y ₂ ′ −Y ₂ is obtained as a function of the y position of the irradiation point of the measurement beam on each Y scale. Similarly, main controller 20 determines unevenness ΔZ ₁ (y) = Z ₁ ′ −Z ₁ , ΔZ _{2 on} the reflecting surface of Y scales 39Y ₁ and 39Y ₂ from the difference between the measured value of the Z head and the corresponding predicted value. (Y) = Z ₂ ′ −Z ₂ is obtained as a function of the y position of the irradiation point of the measurement beam on each Y scale.

e. The main controller 20 is connected to the a. ~ D. Processing of, the irradiation point of measurement beams of Y heads 65 ₃ and Z head _763, sequentially, Y scales 39Y ₁ on the x position _x 1i (i = _1~4), at the same time, Y head 64 ₃ and Z the irradiation point of the heads ₇₄₃ of the measuring beam Y x position _x 2i on the scale 39Y ₂ (i = 1~4), and positioning is performed repeatedly. As a result, the distortions ΔY ₁ (x, y) and ΔY ₂ (x of the diffraction gratings of the Y scales 39Y ₁ and 39Y ₂ are obtained as a two-dimensional function with respect to the x and y positions of the irradiation points of the measurement beam on each Y scale. , Y) and the irregularities ΔZ ₁ (x, y), ΔZ ₂ (x, y) on the diffraction grating surface.

  Here, in the position measurement of wafer stage WST using each interferometer of interferometer system 118, due to air fluctuations (air temperature fluctuations) caused by the temperature change and temperature gradient of the atmosphere on the beam path of the measurement beam, Measurement errors can occur. Therefore, in the above position measurement, it is desirable to drive wafer stage WST at a sufficiently low speed so as not to cause a measurement error due to air fluctuation. Further, the main controller 20 performs measurement of the distortion of the diffraction grating and the unevenness of the diffraction grating surface for each Y scale a plurality of times in order to alleviate the fluctuation error of the interferometer due to the averaging effect. It is desirable to obtain the distortion and unevenness by averaging the results.

In the above measurement processing, the functions ΔY ₁ (x, y), ΔY ₂ (x, y), ΔZ ₁ (x, y), and ΔZ ₂ (x, y) are limited numbers on the x and y coordinates. Is obtained for discrete points. Therefore, main controller 20 complements using an appropriate trial function, and uses the obtained continuous function as first correction data for correcting measurement errors of encoder system 150 and surface position measurement system 180.

In the same manner as described above, main controller 20 measures the distortion of the diffraction gratings of X scales 39X ₁ and 39X ₂ using X head 66, and corrects first measurement data ΔX ₁ for correcting measurement errors caused by the distortion. (X, y), ΔX ₂ (x, y) is created.

The main controller 20 executes the above processing when the exposure apparatus 100 is started, idle, when a predetermined number of wafers are replaced, etc., and the first correction data ΔX ₁ (x, y), ΔX ₂ ( x, y), ΔY ₁ (x, y), ΔY ₂ (x, y), ΔZ ₁ (x, y), ΔZ ₂ (x, y) are created.

  In the above description, as an example, for the encoder system 150, measurement errors due to diffraction grating distortion (in principle, including pitch non-uniformity) are taken up, and for the surface position measurement system 180, the diffraction grating surface ( The case where measurement errors due to the unevenness of the reflection surface are taken up and correction data for these measurement errors is created has been described. However, in the operation of the encoder system 150 and the surface position measurement system 180, instead of these (measurement error due to diffraction grating distortion, measurement error due to unevenness of the diffraction grating surface (reflection surface)), or in addition to these In addition, errors due to deviations in the installation position of the head, damage to the diffraction grating (reflection surface), and the like may be handled. Further, in order to reduce the cost of creating correction data (amount of correction data, creation time, etc.), it is preferable to handle errors that depend only on the x and y positions of the measurement beam irradiation points on the scale. The error due to the scale usually depends only on the x and y positions of the irradiation point of the measurement beam on the scale. It is also good to handle errors that can fluctuate in the short term. Then, for example, every time the exposure of a predetermined number of wafers is completed and the last wafer is replaced, the correction data is appropriately updated according to the above-described procedure. For example, the predetermined number is set to 1 or 25 (the number of one lot). By this handling, measurement errors of the encoder system 150 and the surface position measurement system 180, and even measurement errors that fluctuate in a short period can be reduced or made zero.

  Next, a method for creating the second correction data will be described. Here, the second correction data will be briefly described prior to the description of the creation method.

  Only the first correction data of the measurement errors of the encoder system 150 and the surface position measurement system 180 described above can cope with errors during exposure or wafer alignment due to the position of the wafer stage WST being different. Is difficult. This is because the first correction data is for correcting measurement errors due to deformation of the scale lattice or unevenness of the scale without considering where the wafer stage WST is. This is because it cannot cope with errors due to various factors such as a high-order error component unique to the apparatus.

  Therefore, in order to reduce an error component that cannot be removed even by using the first correction data, it is necessary to correct the error. However, it takes an enormous amount of time to create correction data, which is not preferable because it causes a reduction in throughput.

  Therefore, in the present embodiment, the second correction data for correcting the residual error that cannot be removed only by the correction using the first correction data is created by a simple method as described later.

  As a premise, prior to the creation of the second correction data, the first correction for correcting major errors (low-order components) such as errors caused by the distortion of the diffraction grating and the unevenness of the surface by the above-described procedure. Assume that data has been created.

  Here, the basic concept of creating the second correction data will be described. Since the second correction data is a six-dimensional function, if the second correction data is created in the entire driveable range of wafer stage WST, enormous creation costs (data amount, creation time, etc.) are required. Therefore, in order to reduce the production cost to a practical level, main controller 20 moves wafer stage WST when performing exposure in the step-and-scan mode, not over the entire movable range of wafer stage WST. Second correction data is created for a path (hereinafter referred to as a movement path during exposure), particularly for a scanning speed of each shot area on the wafer and for a constant speed section in which the wafer stage WST before and after that is driven at a constant speed. As a result, the dependency of the second correction data on the XY position (two degrees of freedom) is reduced to the dependency on the Y position (one degree of freedom) on the movement path.

The exposure movement path of wafer stage WST is uniquely determined according to the shot map (size and arrangement of shot areas) of wafer W to be exposed. FIG. 11A shows an exposure moving path BE for a wafer W having 26 shot areas S _i (i = 1 to 26) as an example. Note that the number of shot areas is larger than 26 in an 8-inch wafer or the like mainly used at present, but here, for convenience of illustration and description, a wafer having 26 shot areas is taken up. In FIG. 11A, the exposure center (the optical axis AX of the projection optical system PL, that is, the center of the exposure area IA) moves along the exposure movement path BE with respect to the fixed wafer W. As shown, the wafer stage WST actually moves along a path opposite to the exposure-time movement path BE. During the movement, the movement locus in which the exposure center moves relative to the wafer W is nothing but the exposure movement path BE. In the following, in order to make the description easy to understand, it is assumed that the exposure center moves on the wafer W as appropriate.

  At the time of exposure in the step-and-scan mode, the exposure center starts moving from the start position B shown in FIG. 11A and moves to the end position E without stopping. Move along path BE.

The exposure movement path BE includes two sections. One is a straight section U _i (i = 1 to n (= 26)) parallel to the Y axis shown by a solid line in FIG. 11A, and the other is in FIG. 11A. A curved section A _{j, j + 1} connecting two straight sections U _j , U _{j + 1} indicated by a broken line.

In FIG. 11A, from the viewpoint of avoiding complications in the drawing, straight sections (for example, U ₁₀ , U ₁₁ , U ₂₂ ) aligned in the scanning direction (Y-axis direction) are slightly in the non-scanning direction (X-axis direction). The positions are shifted so as not to overlap each other. These straight sections U _i is a moving path of the exposure center when performing the scanning exposure with respect to the shot area S _i, respectively, are longitudinal in the Y axis direction at the center position in the X-axis direction of the shot areas S _i . In these sections U _i , wafer stage WST is driven at a constant speed.

In the curve section A _{j, j + 1} , the wafer stage WST is moved in the non-scanning direction (X-axis direction) to the point where scanning exposure for a certain shot area S _j is completed and scanning exposure for the next shot area S _{j + 1} is started. Corresponds to the stepping interval between shots. In this inter-shot stepping interval A _{j, j + 1} , wafer stage WST is accelerated in the reverse direction after decelerating to zero speed in the scanning direction in parallel with the stepping in the non-scanning direction. Note that some curve sections, for example, A ₄ and ₅ include a straight section, but scanning exposure is not performed in a section indicated by a broken line in FIG.

In the drive control of wafer stage WST, particularly high drive accuracy (position and speed control accuracy) is required in the straight section U _i of the two sections included in the exposure movement path BE. For this reason, in the present embodiment, the main controller 20 creates the second correction data only for the straight section U _i .

Here, as shown in FIG. 11A, a plurality of straight line sections U _i are intermittently included in the movement path BE during exposure (the number of shot areas is 26). The plurality of straight sections _{U n,} for example, as in the interval _{U 10, U 11, U 22} , contains the Y-axis direction can be connected to a group of sections. Therefore, as shown in FIG. 11B, main controller 20 sets a straight section L _k (k = 1 to m) that connects a group of sections and vertically cuts a plurality of shot areas in the Y-axis direction. To do. For example, the section L ₁ is obtained by connecting the sections U ₁₀ , U ₁₁ , and U ₂₂ . As a result, a plurality of straight sections having different positions in the non-scanning direction, that is, six straight sections L _{1 to} L ₆ in the example of FIG. 11B are obtained. Second correction data is created for these straight line sections L _{1 to} L ₆ .

Even during alignment measurement, high drive accuracy of wafer stage WST is required. Therefore, even for the moving path L _A at the time of alignment measurement shown in FIG. 11 in (B), to create a second correction data. The moving path L _A shows the movement locus to wafer W detection center of primary alignment system AL1 during wafer alignment.

  Further, main controller 20 considers only these primary dependencies with respect to the positions of wafer stage WST in the Z, θx, θy, and θz directions in order to reduce the production cost to a practical level. These higher order dependencies (including dependencies on complex degrees of freedom) are not considered. As a result, the dependence of the second correction data on the Z, θx, θy, and θz positions (four degrees of freedom) is substantially reduced to the dependence on one degree of freedom.

Next, a procedure for creating the second correction data will be described. As a premise, prior to the creation of the second correction data, the first correction for correcting major errors (low-order components) such as errors caused by the distortion of the diffraction grating and the unevenness of the surface by the above-described procedure. Data (ΔX ₁ (x, y), ΔX ₂ (x, y), ΔY ₁ (x, y), ΔY ₂ (x, y), and ΔZ ₁ (x, y), ΔZ ₂ (x, y)) ) Has been created.

  In the creation of the following second correction data, it is assumed that the main controller 20 has corrected the position measurement results of the encoder system 150 and the surface position measurement system 180 using the first correction data.

That is, main controller 20 obtains the x and y positions of the measurement beam irradiation points of each head on each scale from the X and Y positions of wafer stage WST obtained from the measurement results of interferometer system 118, for example. Then, correction amounts ΔX ₁ and ΔX _{2 corresponding} to the measurement results of the X head 66 (66 _{5 to} 66 ₈ and 66 _{1 to} 66 ₄ ) are corrected from the correction data ΔX ₁ (x, y) and ΔX ₂ (x, y). Correction amounts ΔY ₁ and ΔY ₂ for the measurement results of the Y heads 65 and 64 (or 68 and 67) from the data ΔY ₁ (x, y) and ΔY ₂ (x, y) are used as correction data ΔZ ₁ (x, y). , ΔZ ₂ (x, y), the correction amounts ΔZ ₁ and ΔZ ₂ for the measurement results of the Z heads 76 and 74 are extracted. These correction amounts (for example, ΔY ₁ ) are corrected in addition to the measurement value (Y ₁ (= C _Y1 )) of each head (that is, <Y ₁ > = Y ₁ + ΔY ₁ ).

  Hereinafter, the procedure for creating the second correction data will be described in detail.

First, main controller 20 uses interferometer system 118 to monitor position information of wafer stage WST while controlling stage drive system 124 to place wafer stage WST (wafer table WTB) in a reference posture (predetermined Z position). Z ₀ and θx ₀ = θy ₀ = θz ₀ = 0).

Next, main controller 20 drives wafer stage WST in the XY plane and, as shown in FIG. 12, sets start point B ₁ (see FIG. 11 (B)) of linear section L ₁ on wafer W. Positioning is performed on the optical axis (exposure center) AX of the projection optical system PL.

Next, main controller 20 controls stage drive system 124 based on the measurement result of interferometer system 118 (or encoder system 150) to move wafer stage WST in the -Y direction (the white arrow in FIG. 12). Direction). At this time, the exposure center moves in the + Y direction from the start point B ₁ toward the end point E ₁ along the straight line section L ₁ on the wafer W shown in FIG.

As shown in FIG. 12, in a state immediately after the start of constant speed driving, the X head 66 ₇ and the Y heads 65 ₄ and 64 ₅ face the X scale 39X ₁ , the Y scales 39Y ₁ and 39Y ₂ , respectively (measurement). The X, Y, and θz positions of wafer stage WST are measured. Further, Z heads ₇₆ 4, 74 _5, Y scales 39Y _1, opposed to 39Y ₂ (irradiated with measurement beams), Z of the wafer stage WST, measures the θy position.

In FIG. 12, with the wafer stage WST moves in the -Y direction (ie in FIG 11 (B), together with the exposure center is moved on the straight section _{L 1} on the wafer W + Y direction), X scales 39X X head that faces the _first or 39X ₂ are sequentially, X head _{66 7,} 66 _6, 66 5, switched to 66 _4. On the other hand, the Y heads 65 ₄ and 64 ₅ continue to face the Y scales 39Y ₁ and 39Y ₂ without being replaced with other Y heads. Further, Z heads ₇₆ 4, 74 ₅ also without replaced with other Z heads continue to face Y scales 39Y _1, 39Y _2. Therefore, main controller 20 controls X heads 66 _{7 to} 66 ₄ while wafer stage WST moves in a section corresponding to linear section L ₁ on wafer W (while the exposure center moves in linear section L ₁ ). The Y heads 65 ₄ and 64 ₅ and the Z heads 76 ₄ and 74 ₅ are used to measure the X, Y, θz, Z, and θy positions of the wafer stage WST.

Table 1 shows the X head, the Y head, and the Z head that face the corresponding scale when the wafer stage WST moves in a section corresponding to the straight section L ₁ (and L _{2 to} L ₆ , L _A ). ing.

Then, main controller 20 performs X heads 66 _{7 to} 66 ₄ , Y head while wafer stage WST moves on the section corresponding to straight section L ₁ (while the exposure center moves on straight section L ₁ ). 65 _{4, 64} 5, Z head ₇₆ 4, 74 ₅ measurement results (the first correction data corrected measurement result using _{a) <X>, <Y 1} >, <Y 2>, <Z 1>, < From Z ₂ >, the positions (<X>, <Y>, <θz>, <Z>, <θy) of wafer stage WST are obtained via equations (1a) to (1c) and equations (4a) and (4b). >). Here, in order to make it easy to understand that the position (X, Y, θz, Z, θy) of wafer stage WST has been corrected using the first correction data, these are shown in parentheses <>. Yes.

The main controller 20 uses the measurement results (vector P ₁ ≡ (<X>, <Y>, <θz>, <Z>, <θy>)) of the encoder system 150 and the surface position measuring system 180. ) And the corresponding measurement result of the interferometer system 118 (expressed using the vector P ₁ ′ ≡ (X ′, Y ′, θz ′, Z ′, θy ′)) ΔP ₁ = P ₁ '-P ₁ is associated with the Y position of wafer stage WST every time the exposure center moves a predetermined distance on linear section L ₁ as wafer stage WST moves in the -Y direction, that is, the Y position of Obtained as a function ΔP ₁ (Y). However, in this case, the Y position in the function ΔP ₁ (Y) is not the actual measurement value but the Y position as the servo target value.

As the wafer stage WST moves in the −Y direction, the exposure center reaches a point corresponding to the end point E ₁ (see FIG. 11B) of the straight section L ₁ , and the difference ΔP ₁ = P ₁ ′ − When P ₁ is created, the creation of the function ΔP ₁ (Y) ends.

Main controller 20 creates function ΔP _k (Y) for the remaining straight section L _k (k = 2 to 6, A), similarly to straight section L ₁ . In this case, main controller 20 drives wafer stage WST without stopping after exposure center reaches, for example, end point E _k−1 of straight section L _k−1 by movement of wafer stage WST, and exposure center. the move to the starting point B _k of the next straight section L _k. Then, main controller 20 drives wafer stage WST at a constant speed in the + Y direction or the −Y direction while positioning wafer stage WST in the reference posture so that the exposure center moves on straight line section L _k toward end point E _k. To do. For moving the exposure center all straight section _L 1 _~L 6, the upper _{L A} along the shortest path, the main controller 20, the section of the exposure center _{L 1 ~L 3, L A,} L 4 ~L Wafer stage WST is moved in the order of ₆ , and in the opposite order. Therefore, the start point B _k and the end point E _k for the straight section L _k are selected as shown in FIG.

Further, when creating the function ΔP _k (Y) for the straight section L _k (k = 2 to 6, A), it is used to measure the X, Y, θz, Z, and θy positions of the wafer stage WST. The X head, Y head, and Z head to be used are as shown in Table 1. For example, when creating a function [Delta] P ₄ (Y) with respect to the straight line segment _{L 4} are, X head ₆₆ 4 _-66 8, Y head ₆₅ 3, ₆₄ 3, Z head ₇₆ 3, 74 ₃ are used.

Main controller 20 changes position (Z, θx, θy, θz) of wafer stage WST to create function ΔP _k (Y) (k = 1 to 6, A). First, main controller 20 sequentially changes the Z position of wafer stage WST to a plurality of positions including reference position Z ₀ , except that the other θx, θy, θz positions are set as reference positions (θx ₀ , θy ₀ , θz ₀ ). And ΔP _k (Y) is created according to the same procedure as above. Next, main controller 20 sequentially changes the θz position of wafer stage WST to a plurality of positions including reference position θz ₀ , except that the other Z, θx, θy positions are set to reference positions (Z ₀ , θx ₀ , θy _0). ) To create ΔP _k (Y). Similarly, main controller 20 sequentially changes the [theta] y positions of wafer stage WST in a plurality of positions including the reference position [theta] y _0, although other Z, [theta] x, the reference position [theta] z position _{(Z 0, θx 0, θz} 0 ) To create ΔP _k (Y). Further, main controller 20, sequentially changing a plurality of positions including the reference position [theta] x ₀ and [theta] x position of the wafer stage WST, however other Z, [theta] y, the reference position [theta] z position _{(Z 0, θx 0, θz} 0) To create ΔP _k (Y). Of course, these four processes may be performed in any order. In this way, a function ΔP _k (Y, Z, θx, θy, θz) of Y, Z, θx, θy, θz is created. In the following, unless otherwise necessary to _{distinguish, ΔP k (Y, Z,} θx, θy, θz) of briefly, also referred to as [Delta] P _k.

Also in this case, for the same reason as in the case of creating the first correction data, the wafer stage WST is moved at a sufficiently low speed so that the measurement error of the interferometer system 118 due to air fluctuation does not occur in the creation of the function ΔP _k. It is desirable to drive. Similarly to the above, since the fluctuation error of the interferometer is mitigated by the averaging effect, it is desirable to create the function ΔP _k a plurality of times and average the results obtained for the plurality of times to obtain the function ΔP _k. .

In the above process, the function ΔP _k is _obtained for a finite number of discrete points on the Y, Z, θx, θy, and θz coordinates. Therefore, main controller 20 complements using an appropriate trial function, and uses the obtained continuous function as second correction data for correcting measurement errors of encoder system 150 and surface position measurement system 180.

In addition, the straight line section L _k is determined based on a movement path of wafer stage WST during the exposure operation and alignment measurement, and based on a section where particularly high drive control is required. Therefore, the intervals between the discrete points on the Y, Z, θx, θy, and θz coordinates can be determined as necessary.

  Further, as described above, the movement path during exposure (the movement path of wafer stage WST when performing step-and-scan exposure) is uniquely determined according to the shot map of wafer W to be exposed. Therefore, the second correction data must be created for each shot map of the wafer W to be exposed (it is not necessary to create it for each wafer). Therefore, main controller 20, when a new wafer W is placed on wafer stage WST, if second correction data for the shot map of wafer W has not been created, prior to alignment measurement and exposure operation. Then, the second correction data is created according to the above-described procedure. On the other hand, when the corresponding second correction data is created, main controller 20 does not create new second correction data, but uses the created second correction data.

Main controller 20 determines that wafer stage WST is in a straight section L _k (k = 1 to 6) based on the measurement result (or target value data) of interferometer system 118 at the X position of wafer stage WST during operation of the exposure apparatus. , A), the first correction data ΔP _k (Y, Z, θx, θy, θz) corresponding to the straight section L _k is used to determine the first position. Using the correction data, the corrected measurement results of the encoder system 150 and the surface position measurement system 180 (denoted as _Pk for convenience) are further corrected. That is, the main controller 20 extracts the correction amount ΔP _k from the second correction data ΔP _k (Y, Z, θx, θy, θz) using the measurement result of the interferometer system 118, for example, and uses it as the measurement result P _k. (Ie, << P _k >> = P _k + ΔP _k ). The main controller 20 then corrects the measurement result << P _k >> = (<< X >>, << Y >>, << θz >>, << Z >>, << θy >>) and the measurement result of the θx position of the interferometer system 118. Accordingly, the wafer stage WST is driven and controlled. Here, in order to make it easy to understand that the measurement result P _k has been corrected using the second correction data, the measurement result is described in parentheses <<

  As described above, by using the second correction data, the residual error included in the measurement results of the encoder system 150 and the surface position measurement system 180 corrected using the first correction data is used as the measurement accuracy of the interferometer system 118. It is possible to correct to the extent of. Therefore, highly accurate servo control of the position (and speed) of wafer stage WST is possible particularly during scanning exposure and wafer alignment measurement.

In the example described above, the second correction data ΔP _k is created for seven straight line sections L _k (k = 1 to 6, A) having different X positions (see FIG. 11B). Therefore, the straight section L _{k to} be used is uniquely determined from the X position of wafer stage WST. Therefore, main controller 20 removes the X position of wafer stage WST from the second correction data ΔP _k (Y, Z, θx, θy, θz) corresponding to the determined straight section L _k . Using the θx, θy, and θz positions, the correction amount is derived.

The second correction data ΔP _k is created along a straight line section L _k that has no width in the X-axis direction. Therefore, main controller 20, wafer stage WST, as shown in FIG. 13 (A), including the X-axis direction from the straight section L _k within a predetermined distance [Delta] L _k / 2 (the straight section L _k in the center When it is located in the hatched region E _k ), it is considered to be located on the straight line section L _k , and the encoder system 150 and the interferometer system 180 are used by using the corresponding second correction data ΔP _k . The measurement result _Pk is corrected. For example, ΔL _k = 0.1 mm.

The second correction data ΔP _k is not created outside the straight section L _k . Here, the straight section L _k is required during scanning exposure and alignment measurement, which requires a particularly high driving accuracy (position and speed control accuracy) for the wafer stage WST when the exposure apparatus 100 is operating normally. It is determined based on the movement path of the wafer stage WST in the middle. That is, in the straight section L _k off, driving high accuracy of the wafer stage WST as a straight section L _k is not required. Therefore, main controller 20, when the wafer stage WST is located in the outside of the straight section L _k, without using the second correction data, the encoder system 150 and an interferometer that has been corrected using only the first correction data Wafer stage WST is driven and controlled according to the measurement result of system 180.

However, the occurrence of abnormality, as shown in FIG. 13 (A), from the wafer stage WST is on straight section L _k, the point E, further the point E '(given the straight section L _k in the + X direction by a distance [Delta] L _k If outside through / 2 distant points), deviates from the interval L _k at point E ', instantly, the second correction data [Delta] P _k a position measurement result using the correction is interrupted. In other words, the correction amount ΔP _k (indicated by the vertical axis in FIG. 13B) derived from the second correction data ΔP _k (Y, Z, θx, θy, θz) is shown in FIG. As indicated by an arrow 1, the value changes from a finite value to zero at a point E ′ on the movement locus L of wafer stage WST (indicated by the horizontal axis in FIG. 13B). Therefore, the measurement results of the position of wafer stage WST by encoder system 150 and surface position measurement system 180 are discontinuous. This is not preferable in terms of drive control of wafer stage WST.

Therefore, when the wafer stage WST deviates from the straight section L _k , main controller 20 sets the correction amount as wafer stage WST moves away from point E ′ as indicated by arrow 2 in FIG. The correction amount ΔP _k (E ′) at the point E ′ is continuously attenuated to zero. By such processing, the continuity of the position measurement result of wafer stage WST by encoder system 150 and surface position measurement system 180 is guaranteed.

On the other hand, as shown in FIG. 13A, when wafer stage WST enters from the outside of region E _k via point B ′ and B onto straight line section L _k , if it enters region E _k at point B ′. Instantly, correction of the position measurement result using the second correction data ΔP _k is started. Here, the point B ′ is separated from the straight section L _k by a predetermined distance ΔL _k / 2 in the −X direction. In other words, the correction amount ΔP _k (indicated by the vertical axis in FIG. 13C) derived from the second correction data ΔP _k (Y, Z, θx, θy, θz) is shown in FIG. As indicated by an arrow 1, the value changes from zero to a finite value at a point B ′ on the movement locus L of wafer stage WST (indicated by the horizontal axis in FIG. 13C). Therefore, the position measurement result of wafer stage WST becomes discontinuous. This is also undesirable in terms of drive control of wafer stage WST.

Therefore, when wafer stage WST enters linear section L _k , the correction amount is continuously increased as indicated by arrow 2 in FIG. 13C, and second correction data ΔP is obtained at point B ′. It is made to correspond to the correction amount ΔP _k (B ′) derived from _k (Y, Z, θx, θy, θz). By such processing, the continuity of the position measurement result of wafer stage WST by encoder system 150 and surface position measurement system 180 is guaranteed.

Instead of the function [Delta] P _k, using the product of the weight function w _k shown in the function [Delta] P _k and FIG 13 (D) (X-X k), it is also possible to determine the correction amount. The weighting function w _k (X−X _k ) takes the maximum value 1 in the region (region E _k ) within the predetermined distance ΔL _k / 2 from the X position X _k of the corresponding straight line section L _k , and the region E _k The function is attenuated as it deviates from the position X and becomes zero outside the distance ΔL _k ′ / 2 from the X position X _k . By using the weight function w _k (X−X _k ), it is possible to easily execute the process for ensuring the continuity of the correction amount ΔP _k described above. For example, with respect to [Delta] L _k = 0.1 mm, and ΔL _k '= 1mm.

Further, as shown in FIG. 14A, when the scanning exposure of the shot area S _i on the wafer W is completed and the scanning exposure of the next shot area S _{i + 1} is started, the exposure center of the wafer stage WST is from straight section L _k which is constant speed section _{U j} belongs, via the inter-shot stepping interval _{a j, j1} connecting the starting point _{B j + 1} of the end point _{E j} and constant speed section _{U j + 1} of the constant speed section _{U j,} constant speed section _{U j + 1} Is stepped in the −X direction so as to move to the straight line section L _{k + 1} to which. At this time, the correction of the position measurement result using the second correction data ΔP _k is interrupted in the inter-shot stepping interval A _{j, j + 1} as before. In other words, the correction amount ΔP _k (indicated by the vertical axis in FIG. 14B) derived from the second correction data ΔP _k (Y, Z, θx, θy, θz) is shown in FIG. As indicated by an arrow 1, from a finite value to zero at a point E _i ′ on the movement locus L of wafer stage WST (indicated by the horizontal axis in FIG. 14B), from zero at point B _{i + 1} ′. It changes discontinuously to a finite value. Therefore, the position measurement result of wafer stage WST becomes discontinuous. This is also undesirable in terms of drive control of wafer stage WST.

Therefore, main controller 20 moves wafer stage WST through two linear sections via an inter-shot stepping interval, and accordingly, the exposure center moves to two straight lines via, for example, an inter-shot stepping interval A _{i, i + 1.} When moving in the sections L _k and L _{k + 1} , as indicated by the arrow 2 in FIG. 14B, the correction amount ΔP _{k is set} to the end point E _j (the constant speed section U _j belonging to the straight section L _k. Exactly, at a point corresponding to a point E _j ′ separated by a predetermined distance ΔL _k / 2 in the + X direction from the end point E _j (in FIG. 14B, it is indicated by using a symbol E _j ′ for convenience). From the correction amount ΔP _k (E _j ′) derived from the second correction data, the starting point B _{j + 1 of the} constant velocity section U _{j + 1} belonging to the straight section L _{k + 1} (more precisely, a predetermined distance in the −X direction from the starting point B _{j + 1)} [Delta] L _k / 2 points away _{B j + 1} ') corresponding points ( 14 (B) in, for convenience the reference numerals B _{j + 1 'using} shown) by the correction amount [Delta] P k _{+ 1} drawn from the second correction data (B j _{+ 1'),} continuously varied. Alternatively, as described above, instead of the function [Delta] P _k, using the product of the function [Delta] P _k and the weighting function _{w k (X-X k)} , may determine the correction amount. In this case, as shown in FIG. 14C, the correction amount (indicated by the vertical axis in FIG. 14C) is continuously zero from ΔP _k (E _j ′) at the point E _j ′. It decays and increases continuously from zero to change to ΔP _{k + 1} (B _{j + 1} ′) at point B _{j + 1} ′. By such processing, the continuity of the position measurement result of wafer stage WST by encoder system 150 and surface position measurement system 180 is guaranteed.

In the present embodiment, among the movement path of the wafer stage WST during exposure operation and in alignment measurement, from the interval of particularly high driving control is required, defining a straight section L _k for creating a second correction data. However, not only the straight section L _k but also a section where high drive control is required may be taken in according to the correction data creation cost.

As described above in detail, in the exposure apparatus 100 of the present embodiment, the main controller 20 uses the encoder system 150 and the surface position measurement system 180 to create a wafer stage when generating correction information (second correction data). The first position information of WST is measured, the second position information of wafer stage WST is measured using interferometer system 118, and a plurality of straight sections extending in the Y-axis direction according to either the first or second position information Wafer stage WST is driven along a movement path including. Then, first correction data (ΔX ₁ (x, y), ΔX ₂ (x, y), ΔY ₁ (x, y), ΔY ₂ (x, y), ΔZ ₁ (x, y)) created in advance. , ΔZ ₂ (x, y)) is used to correct at least a part of the error caused by the surface (measurement surface) of the diffraction grating of the scale included in the first position information, and the corrected first position information The second correction data (function ΔP _k (Y, Z, θx, θy, θz)) is created in association with the movement path (L _k or BE) from the difference between the first position information and the second position information. The second correction data is data for correcting at least a part of an error (residual error) included in the first position information excluding a part of the error corrected using the first correction data. Therefore, by using the second correction data, the first position information corrected using the first correction data is further corrected, and wafer stage WST is driven with high accuracy based on the corrected position information. It becomes possible. In addition, since the second correction data is created in association with a movement path including a plurality of straight sections (L _k ), unlike the case where the second correction information is created for the entire movement range of wafer stage WST, the second correction data is simplified. In addition, the second correction data can be created in a short time.

In addition, according to the exposure apparatus 100 and the exposure method of the present embodiment, the main position of the first position information and the first position information of the wafer stage WST measured by the encoder system 150 and the surface position measurement system 180 by the main control apparatus 20. First correction data created to correct at least a part of errors caused by the surface (measurement surface) of the diffraction grating of the scale included, and a part of the correction corrected using the first correction data In order to correct at least a part of errors (residual errors) included in the first position information excluding errors, a plurality of constant velocity sections (U _{1 to} U) in which wafer stage WST is driven at a constant velocity during scanning exposure. wafer stage WST is driven using the second correction data created in association with the movement path including _n ). Accordingly, the movement path including a constant velocity interval wafer stage WST is a constant speed drive (U 1 _{~U n),} for example, it can be driven with high precision wafer stage WST in the scanning exposure section, thus high by scanning exposure method An accurate pattern can be transferred (formed) onto the wafer W.

Here, as the second correction data, the function ΔP _k created by the method described in the present embodiment may be used, or data created by another method may be used. As the second correction data, the wafer stage WST performs scanning exposure in order to correct at least a part of errors included in the first position information excluding a part of errors corrected by using the first correction data. Data that is created in association with a movement route that includes a plurality of constant velocity sections (U _{1 to} U _n ) that are sometimes driven at a constant velocity is sufficient.

In the above embodiment, the main controller 20 extracts the correction amount ΔP _k from the second correction data ΔP _k (Y, Z, θx, θy, θz) using the measurement result of the interferometer system 118, for example. Is corrected in addition to the measurement result P _k (ie, << P _k >> = P _k + ΔP _k ), but the present invention is not limited to this. That is, a method of extracting the correction amount from the second correction data using the measurement results of the encoder system 150 and the surface position measurement system 180 (which may or may not be corrected using the first correction data). It is also possible to adopt. Similarly, in the above-described embodiment, the main controller 20 determines the x, Y of the measurement beam irradiation point of each head on each scale from the X, Y position of the wafer stage WST obtained from the measurement result of the interferometer system 118, for example. Although the y position is obtained and the correction amount is derived from the first correction data based on the obtained result, the present invention is not limited to this. That is, it is also possible to employ a method of extracting the correction amount from the first correction data using the measurement results of the encoder system 150 and the surface position measurement system 180. When the correction amount is extracted from the first and second correction data, if the interferometer system is not used, the interferometer system 118 is used when driving the WST of the wafer stage, such as during exposure or wafer alignment measurement. Is not necessary (except for the Y interferometer that measures the θx position).

In the above embodiment, the second correction data ΔP _k is corrected for the measurement results (<X>, <Y>, <θz>, <Z>, <θy>) of the encoder system 150 and the surface position measurement system 180. It was created as correction data for However, the present invention is not limited to this, and the second correction data ΔP _k may be created as correction data for correcting the measurement results of the plurality of heads constituting both the systems 150 and 180. As shown in Table 1 above, with the exception of the X head, for each of the straight sections L _k (k = 1 to 6, A), two heads (Y scales 39Y ₁ and 39Y ₂ facing the Y scale 39Y ₂ ) are used. Y head and two (or four Z heads) are uniquely determined, and in this case, main controller 20 causes linear section L _k (k = 1 to 6, A) shown in Table 1. corresponding one of the X heads, two Y heads, the two Z heads (using the first correction data corrected) measurement results _{<X>, <Y 1>} , <Y 2>, <Z 1> , <Z ₂ > and their predicted values X ′, Y ₁ ′, Y ₂ ′, Z ₁ ′, Z ₂ ′ obtained using the measurement results of the interferometer system 118 ΔX ⁽²⁾ _k = X '-<X>, ΔY ⁽²⁾ _k1 = Y ₁ '-<Y ₁ >, ΔY ⁽²⁾ _k2 = Y ₂ '-<Y ₂ >, ΔZ ⁽²⁾ _k1 = Z ₁ '-<Z ₁ >, ΔZ ⁽²⁾ _k2 = Z ₂ '− <Z ₂ In the same way as above, the main controller 20 may be obtained as a function of the Y position of the wafer stage WST and the function of (Z, θx, θy, θz). Measurement results <X> and <X> (corrected using the first correction data) of one X head, two Y heads, and two Z heads corresponding to the straight section L _k (k = 1 to 6, A) Y ₁ >, <Y ₂ >, <Z ₁ >, <Z ₂ > are each corrected by adding a correction amount derived from the second correction data, for example, the Y head facing the Y scale 39Y ₁ . measurement results to _{<Y 1>, "Y 1} " = <Y 1> + ΔY (2) k1 and corrected. main controller 20, from the measurement results of the corrected five heads, formula (1a) ~ ( 1c) and the equations (4a) and (4b), << X >>, << Y >> of wafer stage WST, θz "," Z "," seek [theta] y "position, according to the determined position may be driven and controlled wafer stage WST.

  In the exposure apparatus 100 of the above embodiment, since the θx position of wafer stage WST is measured by interferometer system 118, the θx position is excluded from the application target of the correction method described above. However, in the case where a Z head is further added and a configuration in which the θx position of wafer stage WST can be measured by two Z heads is adopted, the above-described correction method can also be applied to the θx position.

  In the above-described embodiment, the first correction method for correcting the measurement error of the encoder system 150 and the surface position measurement system 180 due to the measurement surface (scale) using the first correction data, and the correction by the first correction method. Residual errors that could not be corrected by the first correction method with respect to the measurement results of the encoder system 150 and the surface position measurement system 180 that have been completed were extracted from the second correction data according to the measurement result of the position of the wafer stage WST. The concept of using the second correction method for correcting using the correction amount is employed.

  Here, with respect to a measurement error caused by the measurement surface to be corrected by the first correction method, first correction data is created based on the result of measuring the surface shape of the diffraction grating of the scale in advance, and the creation thereof Using the correction data, the position information measurement result of wafer stage WST by encoder system 150 and surface position measurement system 180 is corrected. Therefore, it is preferable that the main correction factors, such as the distortion of the diffraction grating forming the scale described above and the unevenness of the reflecting surface thereof, are the targets of the first correction method. On the other hand, in the second correction method, residual errors that could not be corrected using the first correction method are corrected. Therefore, various error factors for which measurement methods have not been established are preferably corrected. Further, since the residual error that could not be corrected by the first correction method can be corrected by the second correction method, the number of measurement points for creating the first correction data is reduced in consideration of this point. Thus, data necessary for creating the first correction data may be sampled in a shorter time.

  Also, since most of the major error factors of the encoder system 150 and the surface position measurement system 180 can fluctuate in the short term, it is necessary to create or update correction data as appropriate. Therefore, a measurement method with a low production cost should be established for the main error factors and factors that can fluctuate in the short term, and should be corrected by the first correction method. On the other hand, most of the minor error factors rarely fluctuate in the short term, or fluctuate but are negligible, and are therefore subject to the second correction method. In this case, once the second correction data is created, it can be used almost permanently.

  Note that error factors that do not fluctuate in the short term even if they are major, and error factors that are major but for which the measurement method is not sufficiently established (for example, error factors attributable to individual heads), etc. It is good as a target.

  It should be noted that whether each of various error factors of the encoder system 150 and the surface position measurement system 180 is the target of the first and second correction methods is an error factor caused by the measurement surface, a measurement method Is established, whether it is a major error factor, whether it is an error factor that can fluctuate in the short term, the size of the correction data creation cost, the error correction handling cost size, etc. Can be determined according to guidelines.

  Note that the configurations of the encoder system and the surface position measurement system described in the above embodiment are merely examples, and the present invention is of course not limited thereto. For example, in the above-described embodiment, an encoder system having a configuration in which a grating portion (Y scale, X scale) is provided on a wafer table (wafer stage) and a Y head and an X head are disposed outside the wafer stage so as to face the lattice portion. Although the case where it is adopted is exemplified, the present invention is not limited to this. For example, as disclosed in US Patent Application Publication No. 2006/0227309, an encoder head is provided on the wafer stage, and the wafer stage is opposed to the encoder head. You may employ | adopt the encoder system of the structure which arrange | positions a grating | lattice part (For example, the two-dimensional grating | lattice or the two-dimensionally arranged one-dimensional grating | lattice part) outside. In this case, the Z head may also be provided on the wafer stage, and the surface of the lattice portion may be a reflective surface to which the measurement beam of the Z head is irradiated.

  In the above-described embodiment, for example, the case where the encoder head and the Z head are separately provided in the head units 62A and 62C has been described. However, a single unit having the functions of the encoder head and the Z head has been described. The head may be used in place of a set of encoder head and Z head.

  In the above-described embodiment, the case where the present invention is applied to a dry type exposure apparatus that exposes the wafer W without using liquid (water) has been described. No. 99/49504, European Patent Application No. 1420298, International Publication No. 2004/055803 Pamphlet, Japanese Patent Application Laid-Open No. 2004-289126 (corresponding US Pat. No. 6,952,253), and the like. An exposure apparatus that forms an immersion space including an optical path of illumination light between the projection optical system and the wafer, and exposes the wafer with illumination light through the liquid in the projection optical system and the immersion space. The present invention can be applied. Further, the present invention can also be applied to an immersion exposure apparatus disclosed in, for example, International Publication No. 2007/097379 pamphlet (corresponding to US Patent Application Publication No. 2008/088843).

  In the above-described embodiment, the case where the present invention is applied to a scanning exposure apparatus such as a step-and-scan method has been described. However, the present invention is not limited thereto, and the step-and- The present invention can also be applied to a stitch type reduction projection exposure apparatus, a proximity type exposure apparatus, or a mirror projection aligner. Further, as disclosed in, for example, US Pat. No. 6,590,634, US Pat. No. 5,969,441, US Pat. No. 6,208,407, etc. The present invention can also be applied to a multi-stage type exposure apparatus provided with a stage. Further, as disclosed in, for example, WO 2005/074014 pamphlet, an exposure apparatus including a measurement stage including a measurement member (for example, a reference mark and / or a sensor) is provided separately from the wafer stage. The present invention is applicable.

  Further, the projection optical system in the exposure apparatus of the above embodiment may be not only a reduction system but also any of the same magnification and enlargement systems, and the projection optical system PL may be any of a reflection system and a catadioptric system as well as a refraction system. The projected image may be either an inverted image or an erect image. In addition, the illumination area and the exposure area described above are rectangular in shape, but the shape is not limited to this, and may be, for example, an arc, a trapezoid, or a parallelogram.

The light source of the exposure apparatus of the above embodiment is not limited to the ArF excimer laser, but is a KrF excimer laser (output wavelength 248 nm), F ₂ laser (output wavelength 157 nm), Ar ₂ laser (output wavelength 126 nm), Kr ₂ laser ( It is also possible to use a pulse laser light source with an output wavelength of 146 nm, an ultrahigh pressure mercury lamp that emits a bright line such as g-line (wavelength 436 nm), i-line (wavelength 365 nm), and the like. A harmonic generator of a YAG laser or the like can also be used. In addition, as disclosed in, for example, U.S. Pat. No. 7,023,610, a single wavelength laser beam in an infrared region or a visible region oscillated from a DFB semiconductor laser or a fiber laser as vacuum ultraviolet light, For example, a harmonic which is amplified by a fiber amplifier doped with erbium (or both erbium and ytterbium) and wavelength-converted into ultraviolet light using a nonlinear optical crystal may be used.

  In the above embodiment, it is needless to say that the illumination light IL of the exposure apparatus is not limited to light having a wavelength of 100 nm or more, and light having a wavelength of less than 100 nm may be used. For example, in recent years, in order to expose a pattern of 70 nm or less, EUV (Extreme Ultraviolet) light in a soft X-ray region (for example, a wavelength region of 5 to 15 nm) is generated using an SOR or a plasma laser as a light source, and its exposure wavelength Development of an EUV exposure apparatus using an all-reflection reduction optical system designed under (for example, 13.5 nm) and a reflective mask is underway. In this apparatus, since a configuration in which scanning exposure is performed by synchronously scanning the mask and the wafer using arc illumination is conceivable, the present invention can also be suitably applied to such an apparatus. In addition, the present invention can be applied to an exposure apparatus using a charged particle beam such as an electron beam or an ion beam.

  In the above-described embodiment, a light transmission mask (reticle) in which a predetermined light-shielding pattern (or phase pattern / dimming pattern) is formed on a light-transmitting substrate is used. Instead of this reticle, For example, as disclosed in US Pat. No. 6,778,257, an electronic mask (variable shaping mask, which forms a transmission pattern, a reflection pattern, or a light emission pattern based on electronic data of a pattern to be exposed, as disclosed in US Pat. No. 6,778,257. For example, a non-light emitting image display element (spatial light modulator) including a DMD (Digital Micro-mirror Device) may be used.

  Further, for example, the present invention can be applied to an exposure apparatus (lithography system) that forms line and space patterns on a wafer by forming interference fringes on the wafer.

  Further, as disclosed in, for example, US Pat. No. 6,611,316, two reticle patterns are synthesized on a wafer via a projection optical system, and one scan exposure is performed on one wafer. The present invention can also be applied to an exposure apparatus that performs double exposure of shot areas almost simultaneously.

  Note that the object on which the pattern is to be formed in the above embodiment (the object to be exposed to the energy beam) is not limited to the wafer, but other objects such as a glass plate, a ceramic substrate, a film member, or a mask blank. But it ’s okay.

  The use of the exposure apparatus is not limited to the exposure apparatus for semiconductor manufacturing. For example, an exposure apparatus for liquid crystal that transfers a liquid crystal display element pattern onto a square glass plate, an organic EL, a thin film magnetic head, an image sensor ( CCDs, etc.), micromachines, DNA chips and the like can also be widely applied to exposure apparatuses. Further, in order to manufacture reticles or masks used in not only microdevices such as semiconductor elements but also light exposure apparatuses, EUV exposure apparatuses, X-ray exposure apparatuses, electron beam exposure apparatuses, etc., glass substrates or silicon wafers, etc. The present invention can also be applied to an exposure apparatus that transfers a circuit pattern.

  An electronic device such as a semiconductor element includes a step of designing a function / performance of the device, a step of manufacturing a reticle based on the design step, a step of manufacturing a wafer from a silicon material, and the exposure apparatus (pattern forming apparatus) of the above-described embodiment. ) A lithography step for transferring a mask (reticle) pattern onto a wafer, a development step for developing the exposed wafer, an etching step for removing exposed members other than the portion where the resist remains by etching, and etching is completed. It is manufactured through a resist removal step for removing unnecessary resist, a device assembly step (including a dicing process, a bonding process, and a package process), an inspection step, and the like. In this case, in the lithography step, the exposure method described above is executed using the exposure apparatus of the above embodiment, and a device pattern is formed on the wafer. Therefore, a highly integrated device can be manufactured with high productivity.

  The correction information generation method of the present invention corrects a position measurement error of a moving body such as a wafer stage of an exposure apparatus used in a lithography process for manufacturing an electronic device (microdevice) such as a semiconductor element (such as an integrated circuit). Suitable for making. The exposure method and exposure apparatus of the present invention are suitable for forming a pattern on a substrate such as a wafer in a lithography process. The device manufacturing method of the present invention is suitable for manufacturing an electronic device.

It is a figure which shows schematically the structure of the exposure apparatus which concerns on one Embodiment. It is a top view which shows a wafer stage. It is a top view which shows arrangement | positioning of an interferometer with the wafer stage of FIG. FIG. 2 is a plan view showing an arrangement of various measuring devices (encoder, alignment system, multipoint AF system, Z head, etc.) provided in the exposure apparatus of FIG. 1. It is a top view which shows arrangement | positioning of an encoder head (X head, Y head) and an alignment system. It is a top view which shows arrangement | positioning of Z head and a multipoint AF type | system | group. It is a block diagram which shows the main structures of the control system of the exposure apparatus which concerns on one Embodiment. 8A is a diagram for explaining the position measurement of the wafer stage using the encoder and the Z head during the exposure process, and FIG. 8B is a diagram for explaining the position measurement of the wafer stage using the encoder during the alignment measurement. It is a figure for doing. It is a figure for demonstrating the position measurement of the wafer stage using the Z head in focus mapping and focus calibration. It is a figure for demonstrating the method of measuring distortion of a scale and the unevenness | corrugation of the surface using Y head and Z head. FIG. 11A shows a movement path with respect to the wafer at the center of exposure corresponding to the movement path of the wafer stage at the time of step-and-scan exposure, and FIG. 11B shows the second correction data for creating the second correction data. It represents the movement path of the exposure center on the wafer corresponding to the movement path of the wafer stage. It is a figure for demonstrating the procedure which produces 2nd correction data with respect to the linear movement path | route of a wafer stage at the time of scanning exposure. FIGS. 13A to 13D are diagrams for explaining a method of correcting the measurement results of the encoder system and the surface position measurement system using the second correction data. FIGS. 14A to 14C are diagrams for explaining a method of correcting the measurement results of the encoder system and the surface position measurement system using the second correction data during the step drive of the wafer stage. .

Explanation of symbols

20 ... main control unit, 39X _1, 39X ₂ ... X scales 39Y _1, 39Y ₂ ... Y scale, 50 ... stage device, 62a to 62f ... head unit, 64 and 65 ... Y head, 66 ... X heads 67, 68 ... Y head, 70A, 70C ... Y encoder, 70B, 70D ... X encoder, 72a to 72d, 74,76 ... Z head, 100 ... exposure device, 118 ... interferometer system, 124 ... stage drive system, 150 ... encoder System 180, surface position measurement system 200, measurement system PL PL projection optical system PU projection unit W wafer WST wafer stage WTB wafer table

Claims (52)

A correction information creation method for creating correction information for correcting a position measurement error of a moving body that moves within a predetermined plane,
Using a plurality of heads provided on one of the moving body and the outside of the moving body, the measurement surface provided on the other of the moving body and the outside of the moving body is irradiated with measurement light, and the measurement is performed. The first position information of the moving body is measured by receiving light from the surface, and the second position information of the moving body is measured using an interferometer system independent of the plurality of heads. Driving the moving body along a moving path including at least one straight section extending in a predetermined direction within the predetermined plane according to any of the second position information;
The first position information is corrected using the first correction information prepared in advance to correct at least a part of the error caused by the measurement surface included in the first position information, and the corrected Correct at least a part of errors included in the first position information excluding a part of errors corrected using the first correction information from a difference between the first position information and the second position information. Creating second correction information for use in association with the movement route;
Correction information creation method including   The correction information creating method according to claim 1, wherein the movement path includes a plurality of the straight sections having different positions with respect to a direction perpendicular to the predetermined direction within the predetermined plane.   The correction information creating method according to claim 2, wherein the plurality of heads include heads having different positions with respect to the vertical direction.   The correction information creation method according to claim 1, wherein in the driving step, the moving body is driven at a constant speed along the straight section.   The moving path includes a constant speed section in which the moving body moves at a constant speed when an object is placed on the moving body and a pattern is formed on the object. The correction information creation method described in the item. The travel route includes a plurality of the constant velocity sections intermittently,
The correction information creation method according to claim 5, wherein the straight section is obtained by connecting a group of connectable constant speed sections among the plurality of constant speed sections.   The correction information creating method according to claim 6, wherein in the creating step, the second correction information is created in association with the straight line section.   The correction information creating method according to claim 7, wherein, in the creating step, the second correction information is created at a plurality of discrete points on the straight section.   In the creating step, the second correction information is converted into two axial directions orthogonal to each other within the predetermined plane of the movable body on the straight section, a direction perpendicular to the predetermined plane, and two inclinations with respect to the predetermined plane. The correction information creation method according to claim 7 or 8, wherein the correction information is created as a function of a direction and a position in a rotation direction within the predetermined plane.   The correction information creation method according to claim 9, wherein the position of the movable body in the two-axis directions is given from a target position for driving the movable body in the driving step.   In the driving step, the movable body is positioned at one of a plurality of positions including a reference position in one of the vertical direction, the two tilt directions, and the rotation direction, and the other three directions. The correction information creation method according to claim 9 or 10, wherein the driving is performed in the biaxial direction after positioning at a reference position.   The correction information creation method according to claim 11, wherein the movable body is sequentially positioned at each of the plurality of positions.   The correction information creation method according to claim 12, wherein the one direction is sequentially selected from the vertical direction, the two inclination directions, and the rotation direction. The movement path is determined for each size of a partition area on the object on which the pattern is formed,
The correction information creation method according to claim 5, wherein, in the creating step, the second correction information is created for each size.   15. The path according to claim 1, wherein the moving path includes a path along which the moving body moves when an object is placed on the moving body and a mark on the object is detected. Correction information creation method. In the driving step, the moving body is driven a plurality of times along the moving path,
The correction information creating method according to any one of claims 1 to 15, wherein in the creating step, the second correction information is created from an average value of the differences obtained for the plurality of times.   The correction information creation method according to any one of claims 1 to 16, wherein, in the creating step, the second correction information is created for each of the plurality of heads. The measurement surface has a diffraction grating having at least the predetermined direction as a periodic direction in the predetermined plane,
The correction information creation method according to claim 1, wherein the plurality of heads include a head having at least the predetermined direction as a measurement direction.   The first correction information is created for at least one of an error caused by a deviation in installation positions of the plurality of heads, distortion of the diffraction grating, unevenness, damage, and non-uniformity in pitch. The correction information creation method according to claim 18.   The correction information creation method according to claim 1, wherein the plurality of heads include a head whose measurement direction is a direction perpendicular to the predetermined plane.   21. The first correction information is created for at least a part of an error that depends only on a position of an irradiation point on the measurement surface of the measurement light. Correction information creation method.   The correction information creation method according to any one of claims 1 to 21, wherein the first correction information is created for an error that may fluctuate in a short period. The correction information creation method according to any one of claims 1 to 22, further comprising a step of creating the first correction information prior to the driving step. An exposure method for forming a pattern on the object by driving a movable body that can move in a predetermined plane while irradiating the object with an energy beam, and that is movable in the predetermined plane.
Using a plurality of heads provided on one of the moving body and the outside of the moving body, the measurement surface provided on the other of the moving body and the outside of the moving body is irradiated with measurement light, and the measurement is performed. Light from the surface is received to measure the first position information of the moving body, and at least a part of the first position information and an error caused by the measurement surface included in the first position information The first correction information created for correcting the moving object and the second correction information created using the correction information creation method according to any one of claims 1 to 23 , An exposure method including a driving step.   25. In the driving step, second position information of the moving body is further measured using an interferometer system independent of the plurality of heads, and the moving body is driven using the second position information. An exposure method according to 1. An exposure method in which a pattern is formed on an object by scanning exposure in which an object is irradiated with an energy beam and a movable body that holds the object and is movable in a predetermined plane is driven in a scanning direction within the predetermined plane. There,
Using a plurality of heads provided on one of the moving body and the outside of the moving body, the measurement surface provided on the other of the moving body and the outside of the moving body is irradiated with measurement light, and the measurement is performed. Light from the surface is received to measure the first position information of the moving body, and at least a part of the first position information and an error caused by the measurement surface included in the first position information In order to correct at least a part of errors included in the first position information excluding a part of errors corrected using the first correction information created to correct the first correction information and the first correction information And a second correction information created in association with a movement path including a constant speed section in which the moving body is driven at a constant speed, and an exposure method including a step of driving the moving body.   27. In the driving step, second position information of the moving body is further measured using an interferometer system independent of the plurality of heads, and the moving body is driven using the second position information. An exposure method according to 1.   In the driving step, a correction amount is extracted from the first and second correction information using the second position information, the first position information is corrected using the correction amount, and based on the first correction information. The exposure method according to claim 27, wherein the moving body is driven.   The exposure method according to any one of claims 26 to 28, wherein the constant speed section includes a section in which the moving body is driven at a constant speed during the scanning exposure.   30. The exposure method according to any one of claims 26 to 29, wherein the moving path includes a path along which the moving body moves when a mark on the object is detected.   31. The driving step, wherein the first position information is corrected using the second correction information when the moving body is positioned within a predetermined range from the constant velocity section. The exposure method according to item. The second correction information is created for a plurality of discrete points on the constant velocity section,
32. The exposure method according to claim 26, wherein in the driving step, the second correction information is interpolated and used.   33. The exposure method according to any one of claims 26 to 32, wherein, in the driving step, the correction amount is continuously set to zero when the moving body moves out of the constant velocity section.   34. The exposure method according to claim 33, wherein, in the driving step, the correction amount is continuously increased when the moving body enters the constant velocity section.   In the driving step, the moving body moves from one constant speed section to another constant speed section through a decelerating section in which the moving body is accelerated in the reverse direction after being decelerated from the constant speed state. At the time, from the second correction information, the first correction amount at the connection point between the decelerating section and the one constant speed section, and the second correction at the connection point between the decelerating section and the other constant speed section. The first position information when the moving body is located on the decelerating section is corrected using the amount obtained by continuously interpolating the first and second correction amounts. The exposure method according to any one of claims 26 to 34. The second correction information is created for a plurality of positions in a direction perpendicular to the predetermined plane of the moving body, two inclination directions with respect to the predetermined plane, and a rotation direction in the predetermined plane on the constant velocity section. Has been
36. The exposure method according to any one of claims 26 to 35, wherein in the driving step, the second correction information for the plurality of positions is interpolated and used. The second correction information is created for each size of a partition area on the object on which the pattern is formed,
37. The exposure method according to any one of claims 26 to 36, wherein in the driving step, the second correction information corresponding to a size of a partition area on the object held by the moving body is used. The second correction information is created for each of the plurality of heads,
38. The exposure method according to any one of claims 26 to 37, wherein in the driving step, the corresponding second correction information is used.   39. The method according to any one of claims 26 to 38, further comprising: creating the second correction information when the second correction information is not created or cannot be used prior to the driving step. Exposure method.   40. The exposure method according to claim 39, further comprising the step of creating the first correction information prior to the step of creating the second correction information.   The exposure method according to any one of claims 26 to 40, wherein the pattern is formed by irradiating a sensitive layer of the object with an energy beam. A step of forming a pattern on the object using the exposure method according to any one of claims 26 to 41;
Processing the object on which the pattern is formed;
A device manufacturing method including: By scanning exposure for driving the said object while irradiating the energy beam on the object in the scanning direction in the predetermined plane, an exposure apparatus that forms a pattern on the object on the body,
A movable body that holds the object and is movable within the predetermined plane;
It has a plurality of heads provided on one of the moving body and the outside of the moving body, and a measuring surface provided on the other of the moving body and the outside of the moving body using the plurality of heads. A position measurement system that irradiates measurement light, receives light from the measurement surface, and measures first position information of the movable body;
Using the first position information, first correction information created to correct at least a part of the error caused by the measurement surface included in the first position information, and the first correction information In order to correct at least a part of the error included in the first position information excluding a part of the corrected error, the moving body is associated with a moving path including a constant speed section in which the moving body is driven at a constant speed. A drive system that drives the movable body using the generated second correction information;
An exposure apparatus comprising: An interferometer system independent of the position measurement system for measuring the second position information of the mobile body;
44. The exposure apparatus according to claim 43, wherein the drive system further drives the movable body using the second position information.   The drive system derives a correction amount from the first and second correction information using the second position information, corrects the first position information using the correction amount, and based on the first correction information The exposure apparatus according to claim 44, wherein the moving body is driven. The second correction information is created for each size of a partition area on the object on which the pattern is formed,
The exposure apparatus according to any one of claims 43 to 45, wherein the drive system uses the second correction information corresponding to a size of a partition area on the object held by the moving body. The second correction information is created for each of the plurality of heads,
47. The exposure apparatus according to any one of claims 43 to 46, wherein the drive system uses the corresponding second correction information.   48. The exposure apparatus according to any one of claims 43 to 47, wherein the drive system creates the second correction information when the second correction information is not created or cannot be used.   49. The exposure apparatus according to claim 48, wherein the drive system creates the first correction information prior to creating the second correction information. The measurement surface has a diffraction grating whose periodic direction is at least one axial direction in the predetermined plane,
The exposure apparatus according to any one of claims 43 to 49, wherein the plurality of heads include heads having at least the one axis direction as a measurement direction.   51. The exposure apparatus according to claim 43, wherein the plurality of heads include heads whose measurement direction is a direction perpendicular to the predetermined plane.   52. The exposure apparatus according to any one of claims 43 to 51, further comprising a pattern generation device configured to irradiate an energy beam to a sensitive layer included in the object to form the pattern.

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