HK1136864A - Moving body driving system, pattern forming apparatus, exposure apparatus, exposure method and device manufacturing method - Google Patents

Description

Moving body drive system, pattern forming apparatus, exposure apparatus and exposure method, and device manufacturing method

[ technical field ] A method for producing a semiconductor device

The present invention relates to a movable body drive system, a pattern forming apparatus, an exposure method, and a device manufacturing method, and more particularly, to a movable body drive system that measures the position of a movable body using an encoder system and drives the movable body substantially along a predetermined plane, a pattern forming apparatus provided with the movable body drive system, an exposure method using the movable body drive system, and a device manufacturing method using the exposure apparatus or the exposure method.

[ background of the invention ]

Conventionally, in a photolithography process for manufacturing a microdevice (electronic device) such as a semiconductor device or a liquid crystal display device, a projection exposure apparatus of a step-and-repeat method (so-called stepper) or a projection exposure apparatus of a step-and-scan method (so-called scanning stepper (also called scanner)) is mainly used.

In such an exposure apparatus, position measurement of a stage holding a substrate to be exposed, for example, a wafer, is generally performed using a laser interferometer. However, with the miniaturization of the pattern accompanying the high integration of the semiconductor element, the required performance has become increasingly stringent. For example, the allowable value of the total overlay error is on the order of several nm, and accordingly, the allowable value of the position control error of the stage is also on the order of sub-nanometer or less. Therefore, short-term fluctuations in the measured value due to air fluctuations caused by temperature changes and/or temperature gradients in the ambient atmosphere on the beam path of the laser interferometer cannot be ignored.

Therefore, recently, a high-resolution encoder which is less susceptible to air shake than an interferometer has attracted attention, and an exposure apparatus using the encoder for position measurement of a wafer stage or the like has been proposed (see, for example, patent document 1). The exposure apparatus described in patent document 1 uses a louver (GRID PLATE) over a wide range including the entire range of movement of the substrate table above the substrate table.

However, since it is difficult to manufacture a large-area and high-precision louver as disclosed in patent document 1, a plurality of louvers must be arranged in an array. Further, the use of a grid plate having a large area as disclosed in patent document 1 is difficult in terms of layout and accuracy, and is not a practical method in terms of cost.

[ patent document 1] specification of U.S. patent application publication No. 2006/0227309

[ summary of the invention ]

In view of the above, the present invention provides a 1 st moving body drive system for driving a moving body substantially along a predetermined plane, the system comprising: a 1 st scale which is arranged on a 1 st surface parallel to the predetermined plane and opposed to the movable body with a 1 st direction as a longitudinal direction and on which a 1 st grating with a periodic direction of the 1 st direction or a 2 nd direction perpendicular to the 1 st direction is formed; a 2 nd scale arranged on the 1 st surface with the 2 nd direction as a longitudinal direction, and having a 2 nd grating with a period direction orthogonal to the 1 st grating; a measurement system having: a 1 st head group including a plurality of 1 st heads disposed on a 2 nd surface of the movable body substantially parallel to the predetermined plane at different positions in the 2 nd direction, the 1 st heads having a periodic direction of the 1 st grating as a measurement direction; and a 2 nd head group including a plurality of 2 nd heads disposed on the 2 nd surface of the movable body at positions different in the 1 st direction and having a periodic direction of the 2 nd grating as a measurement direction, the measurement system calculating position information of the movable body in at least two degrees of freedom directions within the predetermined plane including the 1 st and 2 nd directions, based on an output of the 1 st head facing the 1 st scale and an output of the 2 nd head facing the 2 nd scale; and a drive system for driving the movable body along the predetermined plane based on the position information calculated by the measurement system.

As described above, the measurement system calculates the position information of the movable body in at least two degrees of freedom directions in a predetermined plane including the 1 st and 2 nd directions from the output of the 1 st head facing the 1 st scale and the output of the 2 nd head facing the 2 nd scale, and the drive system drives the movable body along the predetermined plane based on the position information calculated by the measurement system. Therefore, it is not necessary to arrange a scale (grating) corresponding to the entire range of movement of the movable body, and the movable body can be driven along a predetermined plane with good accuracy in the entire range of movement of the movable body based on the measurement value of the measurement system.

From the viewpoint of the 2 nd aspect, the present invention provides a 2 nd moving body drive system for driving a moving body substantially along a predetermined plane, comprising: a scale which is arranged on a 1 st surface parallel to the predetermined plane and opposed to the movable body with a 1 st direction as a longitudinal direction and on which a two-dimensional grating with the 1 st direction and a 2 nd direction perpendicular to the 1 st direction as a periodic direction is formed; a measurement system having a plurality of two-dimensional heads disposed on a 2 nd surface of the movable body substantially parallel to the predetermined plane at positions different in the 2 nd direction and having the 1 st and 2 nd directions as measurement directions, and calculating position information of the movable body in at least two degrees of freedom directions within the predetermined plane including the 1 st and 2 nd directions from outputs of the two-dimensional heads facing the scale; and a drive system for driving the movable body along the predetermined plane based on the position information calculated by the measurement system.

As described above, the position information of the movable body in at least two degrees of freedom directions in a predetermined plane including the 1 st and 2 nd directions is calculated by the measurement system based on the output of the two-dimensional head facing the scale, and the movable body is driven along the predetermined plane by the drive system based on the position information calculated by the measurement system. Therefore, it is not necessary to arrange a scale (grating) corresponding to the entire range of movement of the movable body, and the movable body can be driven along a predetermined plane with good accuracy in the entire range of movement of the movable body based on the measurement value of the measurement system.

From the viewpoint of the 3 rd aspect, the present invention is a pattern forming apparatus for forming a pattern on an object, comprising: a patterning device that generates a pattern on the object; and either one of the 1 st and 2 nd movable body drive systems according to the present invention, wherein the movable body on which the object is mounted is driven by the movable body drive system in order to form the pattern on the object.

According to the above, the patterning device generates the pattern on the object on the movable body driven with good accuracy by either one of the 1 st and 2 nd movable body driving systems according to the present invention, and the pattern can be formed on the object with good accuracy.

From the 4 th viewpoint, the present invention is a 1 st exposure apparatus for forming a pattern on an object by irradiation with an energy beam, comprising: a patterning device for irradiating the object with the energy beam; and any one of the 1 st and 2 nd mobile body drive systems of the invention; in order to move the energy beam relative to the object, the moving body on which the object is mounted is driven by the moving body driving system.

According to the above, in order to move the energy beam irradiated from the patterning device to the object relative to the object, the movable body on which the object is mounted is driven with good accuracy by any one of the 1 st and 2 nd movable body driving systems according to the present invention. Therefore, a pattern can be formed on an object with good accuracy by scanning exposure.

From the 5 th viewpoint, the present invention is a 2 nd exposure apparatus for exposing an object with an energy beam, comprising: a movable body capable of holding the object to move along a predetermined plane; a scale substantially parallel to the predetermined plane and arranged with the 1 st direction as a longitudinal direction; and an encoder system that has a plurality of heads provided on the movable body and having different positions in a 2 nd direction orthogonal to the 1 st direction in the predetermined plane, and that measures position information of the movable body by at least one of the plurality of heads facing the scale at least at the time of exposure of the object.

According to the above, the plurality of heads of the encoder system are provided on the movable body, and at least one of the plurality of heads facing the scale (arranged substantially parallel to the predetermined plane and having the 1 st direction as the longitudinal direction) measures the position information of the movable body at least at the time of exposure of the object.

From the 6 th viewpoint, the present invention is a 1 st device manufacturing method comprising: an operation of exposing the object by using either one of the 1 st and 2 nd exposure apparatuses according to the present invention; and an act of developing the exposed object.

From the 7 th viewpoint, the present invention is a 1 st exposure method for exposing an object with an energy beam, comprising: an operation of holding the object by a movable body; and an operation of driving the movable body by any one of the 1 st and 2 nd movable body driving systems of the present invention and exposing the object with the energy beam.

According to the above, since the moving body holding the object is driven with high accuracy by either of the 1 st and 2 nd moving body driving systems according to the present invention, the object can be exposed well.

From the viewpoint of the 8 th aspect, the present invention is a 2 nd exposure method for exposing an object held by a movable body that moves substantially along a predetermined plane to an energy beam, characterized in that: a 1 st scale in which a 1 st direction is a longitudinal direction and a 1 st grating in which a 2 nd direction perpendicular to the 1 st direction or the 1 st direction is a periodic direction is formed, and a 2 nd scale in which the 2 nd direction is a longitudinal direction and a 2 nd grating in which a periodic direction is orthogonal to the 1 st grating are formed are arranged on a 1 st surface parallel to the predetermined plane to which the movable body is opposed; and comprises: a measurement step of calculating position information of the moving body in at least two degrees of freedom directions within the predetermined plane including the 1 st and 2 nd directions, from an output of the 1 st head facing the 1 st scale and an output of the 2 nd head facing the 2 nd scale, among a 1 st head group including a plurality of 1 st heads and a 2 nd head group including a plurality of 2 nd heads, the plurality of 1 st heads being arranged on a 2 nd surface of the moving body substantially parallel to the predetermined plane such that positions of the 2 nd direction are different and a periodic direction of the 1 st grating is a measurement direction, and the plurality of 2 nd heads being arranged on the 2 nd surface of the moving body such that positions of the 1 st direction are different and a periodic direction of the 2 nd grating is a measurement direction; and a driving step of driving the movable body along the predetermined plane based on the position information calculated in the measuring step.

As described above, the position information of the movable body in at least two degrees of freedom directions in a predetermined plane including the 1 st and 2 nd directions is calculated from the output of the 1 st head facing the 1 st scale and the output of the 2 nd head facing the 2 nd scale, and the movable body is driven along the predetermined plane based on the position information calculated by the measurement system. Therefore, it is not necessary to arrange a scale (grating) corresponding to the entire range of movement of the movable body, and the movable body can be driven along a predetermined plane with high accuracy based on the measurement value of the measurement system in the entire range of movement of the movable body, and the object held by the movable body can be exposed with high accuracy.

From a 9 th aspect, the present invention provides a 3 rd exposure method for exposing an object held by a movable body that moves substantially along a predetermined plane to an energy beam, comprising: a scale having a 1 st direction as a longitudinal direction and a two-dimensional grating having the 1 st direction and a 2 nd direction perpendicular to the 1 st direction as a periodic direction is arranged on a 1 st surface parallel to the predetermined plane, the surface facing the movable body, the method including: a measurement step of calculating position information of the moving body in at least two degrees of freedom directions within the predetermined plane including the 1 st and 2 nd directions, based on outputs of two-dimensional heads facing the scale, the two-dimensional heads being arranged on a 2 nd surface of the moving body substantially parallel to the predetermined plane at different positions in the 2 nd direction and having the 1 st and 2 nd directions as measurement directions; and a driving step of driving the movable body along the predetermined plane based on the position information calculated in the measuring step.

As described above, the position information of the movable body in at least two degrees of freedom directions in a predetermined plane including the 1 st and 2 nd directions is calculated from the output of the two-dimensional head facing the scale, and the movable body is driven along the predetermined plane based on the position information calculated by the measurement system. Therefore, it is not necessary to arrange a scale (grating) corresponding to the entire range of movement of the movable body, and the movable body can be driven along a predetermined plane with high accuracy based on the measurement value of the measurement system in the entire range of movement of the movable body, and the object held by the movable body can be exposed with high accuracy.

From a 10 th viewpoint, the present invention is a 4 th exposure method for exposing an object held by a movable body movable along a predetermined plane with an energy beam, characterized in that: an encoder system including a plurality of heads provided on the movable body and having different positions in a 2 nd direction orthogonal to the 1 st direction in the predetermined plane is used, and position information of the movable body is measured at least at the time of exposure of the object by at least one of the plurality of heads which is substantially parallel to the predetermined plane and faces a scale arranged with the 1 st direction as a longitudinal direction.

According to the above, using an encoder (in which a plurality of heads having different positions in the 2 nd direction are provided on a movable body), at least at the time of exposure of an object, the position information of the movable body is measured by at least one head of the plurality of heads opposed to a scale (arranged substantially parallel to a predetermined plane and having the 1 st direction as the longitudinal direction).

From the 11 th viewpoint, the present invention is a 2 nd device manufacturing method comprising: an operation of exposing the object by using any one of the 2 nd, 3 rd, and 4 th exposure methods of the present invention; and an act of developing the exposed object.

[ description of the drawings ]

FIG. 1 is a schematic configuration diagram showing an exposure apparatus according to an embodiment.

Fig. 2 is a diagram showing an enlarged view of a portion of the vicinity of the stage device of fig. 1.

Fig. 3 is a plan view showing the wafer stage together with an encoder and an interferometer for measuring positional information of the wafer stage.

Fig. 4 is a block diagram showing a related control system for stage control of the exposure apparatus according to an embodiment, with a part omitted.

Fig. 5(a) is a diagram showing a state in which a wafer stage is present at a position immediately below the projection unit in the vicinity of the center of the wafer, and fig. 5(B) is a diagram showing a state in which a wafer stage is present at a position immediately below the projection unit in the vicinity of the middle between the center and the outer periphery of the wafer.

Fig. 6(a) is a diagram showing a state in which the wafer stage is positioned at a position immediately below projection unit PU in the vicinity of the + Y side edge of the wafer, and fig. 6(B) is a diagram showing a state in which the wafer stage is positioned at a position immediately below projection unit PU in the vicinity of the edge in a direction of 45 ° with respect to the X axis and the Y axis when viewed from the wafer center.

Fig. 7 is a diagram showing a state in which the wafer stage is positioned in the vicinity of the + X-side edge of the wafer and at a position directly below projection unit PU.

Fig. 8 is a diagram showing an encoder system for a wafer stage according to another embodiment.

Fig. 9 is a diagram showing an encoder system for a wafer stage according to another embodiment.

[ embodiment ] A method for producing a semiconductor device

An embodiment of the present invention will be described below with reference to fig. 1 to 7.

Fig. 1 shows a schematic configuration of an exposure apparatus 100 according to an embodiment. The exposure apparatus 100 is a reduced projection exposure apparatus of a step-and-scan method, a so-called scanner. As will be described later, in the present embodiment, the projection optical system PL is provided, and in the following description, a direction parallel to the optical axis AX of the projection optical system PL is referred to as a Z-axis direction, a direction in which the reticle and the wafer are relatively scanned in a plane orthogonal to the Z-axis direction is referred to as a Y-axis direction, a direction orthogonal to the Z-axis and the Y-axis is referred to as an X-axis direction, and directions of rotation (inclination) about the X-axis, the Y-axis, and the Z-axis are referred to as θ X, θ Y, and θ Z directions, respectively.

The exposure apparatus 100 includes: illumination system 10, reticle stage RST holding reticle R, projection unit PU, wafer stage device 12 including wafer stage WST on which wafer W is placed, and control systems for these.

The illumination system 10, as disclosed in, for example, U.S. patent application publication No. 2003/0025890, includes an illumination optical system including: a light source, an illumination uniformizing optical system including an optical integrator and the like, and a reticle blind and the like (all not shown). The illumination system 10 illuminates a slit-shaped illumination region IAR on a reticle R defined by a reticle blind (mask system) with illumination light (exposure light) IL at a substantially uniform illuminance. Here, as an example, an ArF excimer laser beam (wavelength 193nm) is used as the illumination light IL.

A reticle R having a pattern surface (lower surface in fig. 1) on which a circuit pattern and the like are formed is fixed to the reticle stage RST by, for example, vacuum suction. Reticle stage RST can be driven slightly in the XY plane by reticle stage drive system 11 including, for example, a linear motor, and can be driven in the scanning direction (the Y-axis direction, which is the left-right direction in the drawing of fig. 1) at a predetermined scanning speed.

The positional information (including the rotation information in the θ z direction) of reticle stage RST in the XY plane (moving surface) is detected at all times with a resolution of, for example, about 0.25nm, based on fixed mirror 14 (actually, each of the fixed mirrors X and Y) fixed to the side surface of lens barrel 40 (constituting projection unit PU) by moving mirror 15 (actually, a Y moving mirror (or retroreflector) having a reflecting surface orthogonal to the Y axis direction and an X moving mirror having a reflecting surface orthogonal to the X axis direction) from reticle laser interferometer (hereinafter, referred to as "reticle interferometer") 16 shown in fig. 1.

Projection unit PU is held by a part of a main body (not shown) (a lens barrel holder) via a flange FLG below reticle stage RST in fig. 1. The projection unit PU includes: a cylindrical barrel 40 having a flange FLG provided near a lower end of an outer peripheral portion thereof; and a projection optical system PL composed of a plurality of optical elements held in the lens barrel 40. As the projection optical system PL, for example, a refractive optical system composed of a plurality of optical elements (lens elements) arranged along the optical axis AX parallel to the Z-axis direction is used. The projection optical system PL is, for example, telecentric on both sides and has a predetermined projection magnification (for example, 1/4 times or 1/5 times). Therefore, when the illumination area IAR is illuminated with the illumination light IL from the illumination system 10, the circuit pattern reduced image (a partial reduced image of the circuit pattern) of the reticle R in the illumination area IAR is formed in an area (exposure area) conjugate to the illumination area IAR on the wafer W whose surface is coated with the resist (sensor) and which is arranged on the 2 nd surface (image surface) side of the projection optical system PL, via the projection optical system PL, by the illumination light IL of the reticle R whose pattern surface is arranged to substantially coincide with the 1 st surface (object surface) of the projection optical system PL. Next, by synchronously driving 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 wafer W is moved relative to exposure area (illumination light IL) in the scanning direction (Y-axis direction), thereby scanning and exposing one shot (shot) area (divided area) on wafer W and transferring the pattern of reticle R to the shot area. That is, in the present 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 with the illumination light IL.

Wafer stage device 12 includes: a stage base 71 supported substantially horizontally by a plurality of (for example, three or four) vibration-proof mechanisms (not shown) disposed on a base plate BS provided on the floor surface F; a wafer stage WST disposed above the stage base 71; a wafer stage drive system 27 (not shown in fig. 1, see fig. 4) that drives the wafer stage WST, and the like.

Stage base 71 is formed of a member having a flat plate-like outer shape, and the flatness of the upper surface thereof is made extremely high, and it serves as a guide surface for movement of wafer stage WST. Inside the stage base 71, a coil unit including a plurality of coils arranged in a matrix shape with the XY two-dimensional direction as the row direction and the column direction is housed.

Wafer stage WST includes a stage main body 30 and a wafer table WTB on the upper side thereof, and a magnet unit 31 having a plurality of magnets, which constitutes a magnetic levitation type planar motor together with the coil unit, is provided on the bottom of stage main body 30, as shown in fig. 2. In the present embodiment, the coil unit includes not only the X-axis direction drive coil and the Y-axis direction drive coil but also the Z-axis direction drive coil, and the moving magnet type planar motor (two-dimensional linear actuator) of an electromagnetic force drive method (lorentz force drive method) for driving the wafer stage WST in six degrees of freedom of the X-axis direction, the Y-axis direction, the Z-axis direction, the θ X direction, the θ Y direction, and the θ Z direction is configured by these coil unit and the magnet unit. Including the above-described planar motor, constitutes wafer stage drive system 27. In the present embodiment, the magnitude and direction of the current supplied to each coil constituting the coil unit are controlled by the main control device 2 θ.

Wafer stage WST may have a structure including a stage main body (driven in the XY plane by a linear motor, a planar motor, or the like, for example) and a wafer stage (driven in three degrees of freedom in at least the Z-axis direction, the θ x direction, and the θ y direction on the stage main body by a voice coil motor or the like). In this case, for example, a planar motor driven by a lorentz electromagnetic force disclosed in U.S. patent No. 5,196,745 specification or the like can be used. Further, the present invention is not limited to the lorentz electromagnetic force driving method, and a variable magnetic resistance driving method of a planar motor may be used.

The wafer W is placed on the wafer table WTB by a wafer holder (not shown) and fixed by, for example, vacuum suction (or electrostatic suction).

The positional information of wafer stage WST in the XY plane can be measured by encoder system 50 (see fig. 4) including scale members 46B, 46C, 46D, and the like shown in fig. 1 and wafer laser interferometer system (hereinafter simply referred to as "interferometer system") 18. The configurations of encoder system 50 for wafer stage WST and interferometer system 18, and the like, will be described in detail below. Further, the scale member may also be referred to as a grating plate, a grating member, a reference member, or the like.

On the upper surface of wafer table WTB (wafer stage WST), as shown in the plan view of fig. 3, a plurality of (10 in each case) X heads (hereinafter, referred to as heads) 66 are provided so as to surround wafer W₁～66₁₀And a Y head (hereinafter referred to as a head for short as appropriate) 64₁～64₁₀. More specifically, X heads 66 are disposed on the + Y side end and the-Y side end of the upper surface of wafer table WTB at predetermined intervals in the X-axis direction₁、66₂、...66₅And 66₆、66₇、...66₁₀. Y heads 64 are arranged at predetermined intervals in the Y-axis direction at the + X-side end and the-X-side end of the upper surface of wafer table WTB₁、64₂、...64₅And 64₆、64₇、...64₁₀. As Y read head 64₁～64₁₀And X head 66₁～66₁₀As the heads of (i), those having the same configuration as the heads (encoders) disclosed in, for example, U.S. patent No. 7,238,931 or international publication No. 2007/083758 pamphlet (corresponding to U.S. patent application publication No. 2007/0288121) are used. Further, the Y head 64 is described below₁～64₁₀And X read head 66₁～66₁₀Also described as Y head 64 and X head 66, respectively.

On the other hand, as is apparent from fig. 1 and 3, four scale members 46A to 46D are arranged so as to surround the periphery of the lowermost end portion of the projection unit PU from four directions. Although not shown in fig. 1 to avoid the complicated drawing, the scale members 46A to 46D are actually fixed to the lens barrel fixing base in a suspended state by a support member, for example.

The scale members 46A, 46C are disposed symmetrically with respect to the optical axis AX of the projection optical system PL with the X-axis direction being the longitudinal direction on the-X side and the + X side of the projection unit PU, respectively. The scale members 46B and 46D are disposed symmetrically with respect to the optical axis AX of the projection optical system PL with the Y-axis direction being the longitudinal direction on the + Y side and the-Y side of the projection unit PU, respectively.

The scale members 46A to 46 are made of the same material (e.g., ceramic, low thermal expansion glass, or the like), and the same reflective diffraction grating having a periodic direction perpendicular to the longitudinal direction is formed on the surface (the lower surface in fig. 1, i.e., the surface on the-Z side). The diffraction grating is formed by scribing at a pitch of, for example, 138nm to 4 μm, for example, 1 μm. In addition, the pitch of the grating is shown to be very wider than the actual pitch in fig. 3 for ease of illustration. A cover member (e.g., a glass plate) substantially transparent to the measuring beam from the head may be provided on the surfaces (grating surfaces) of the scale members 46A to 46D.

The scale members 46A and 46C are used to measure the position of the wafer stage WST in the Y-axis direction, because the diffraction grating is periodic in the Y-axis direction. Further, since the diffraction grating is periodic in the X-axis direction, the scale members 46B and 46D are used for measuring the position of wafer stage WST in the X-axis direction.

In the present embodiment, the X heads 66 are arranged at intervals such that two adjacent X heads 66 can simultaneously face the corresponding scale member (diffraction grating), that is, at intervals equal to or less than the length of the diffraction grating in the direction (arrangement direction of the diffraction gratings) orthogonal to the longitudinal direction of the scale members 46B, 46D₁、66₂、...66₅And 66₆、66₇、...66₁₀Is disposed on the wafer table WTB.

Similarly, the Y heads 64 are arranged at intervals such that two adjacent Y heads 64 can simultaneously face the corresponding scale member (diffraction grating), that is, at intervals equal to or smaller than the length of the diffraction grating in the direction (arrangement direction of the diffraction gratings) orthogonal to the longitudinal direction of the scale members 46A and 46C₁、64₂、...64₅And 64₆、64₇、...64₁₀Is disposed on the wafer table WTB.

Y read head 64₁、64₂、...64₅And 64₆、64₇、...64₁₀Each head of (a) faces either one of the scale members 46C and 46A, and constitutes a multi-eye, more precisely, 5-eye Y linear encoder for measuring the Y position of wafer stage WST. X head 66₁、66₂、...66₅And 66₆、66₇、...66₁₀Each head of (a) faces either one of the scale members 46B and 46D, and constitutes a multi-eye, more precisely, 5-eye X linear encoder for measuring the X position of wafer stage WST.

On the wafer W, a projection optical system PL (projection unit PU)) Within the range of movement of wafer stage WST at the time of lower exposure, Y head 64_i(i is any one of 1 to 5), 64_j(j + i +5) respectively oppose the scale members 46C, 46A, and the X head 66_p(p is any one of 1 to 5), 66_q(q ═ p +5) respectively oppose the scale members 46B, 46D. That is, the Y head 64 facing the scale members 46C, 46A, respectively_i，64_jA pair of Y linear encoders 50C, 50A (see FIG. 4) and an X head 66 facing the scale members 46B, 46D, respectively_p，66_qThe measured values of the total of four encoders of the pair of X linear encoders 50B, 50D (see fig. 4) thus configured are supplied to the main controller 20. The encoder system 50 of fig. 4 is configured to include a pair of Y linear encoders 50C, 50A and a pair of X linear encoders 50B, 50D.

Interferometer system 18 irradiates a reflection surface formed on an end surface of wafer table WTB and movable mirror 43 fixed to stage body 30 with a distance measuring beam as shown in fig. 2, thereby constantly detecting positional information of wafer stage WST with a resolution of, for example, about 0.25 nm. At least a part of the interferometer system 18 (e.g., an optical unit other than the light source) is fixed to the lens barrel fixing base in a suspended state.

Although, as shown in fig. 3, actually, a reflection surface 17Y orthogonal to the Y-axis direction as the scanning direction and a reflection surface 17X orthogonal to the X-axis direction as the non-scanning direction are formed on wafer stage WST, fig. 1 representatively shows only these as reflection surfaces 17.

Interferometer system 18 is shown in FIG. 3 and includes a wafer Y interferometer 18Y and two wafer X interferometers 18X₁And 18X₂And a pair of Z interferometers 18Z₁，18Z₂Five interferometers. As these five interferometers 18Y, 18X₁、18X₂、18Z₁、18Z₂An interferometer, i.e., a michelson type heterodyne laser interferometer using a dual-frequency laser using the zeeman effect, is used. As the wafer Y interferometer 18Y, a wafer Y interferometer having a plurality of measurement axes (including two measurement axes with respect to the distance passing through the projection optical system PL) as shown in FIG. 3 is usedA multi-axis interferometer having an optical axis AX (the center of an exposure region conjugate to the illumination region IAR) and an axis (reference axis) parallel to the Y axis and aligned with the detection center of the alignment system ALG described later. The wafer Y interferometer 18Y is left to be described later.

Wafer X interferometer 18X₁The distance measuring beam is irradiated on the reflection surface 17X along the distance measuring axis (passing through an axis (reference axis) parallel to the X axis and passing through the optical axis AX of the projection optical system PL (the center of the exposure area). The wafer X interferometer 18X₁The displacement of reflection surface 17X with reference to the reflection surface of the X-fixed mirror fixed to the side surface of lens barrel 40 of projection unit PU is measured as position information of wafer stage WST in the X-axis direction.

Wafer X interferometer 18X₂The distance measuring beam is irradiated to the reflecting surface 17X along the distance measuring axis in the X-axis direction passing through the detection center of the alignment system ALG, and the displacement of the reflecting surface of the moving mirror 17X with respect to the reflecting surface of the fixed mirror fixed to the side surface of the alignment system ALG is measured as the position information of the wafer stage WST in the X-axis direction.

As shown in fig. 1 and 2, a movable mirror 43 having an X-axis direction as a longitudinal direction is attached to the + Y side surface of stage body 30 by a dynamic support mechanism, not shown.

A pair of Z interferometers 18Z for irradiating the movable mirror 43 with a distance measuring beam are arranged to face the movable mirror 43₁，18Z₂(refer to fig. 3). More specifically, as is clear from fig. 2 and 3, the movable mirror 43 is formed of a member having a hexagonal cross-sectional shape in which the length in the X-axis direction is longer than the reflection surface 17Y (wafer table WTB) and a rectangle is integrated with an isosceles trapezoid. The surface on the + Y side of the moving mirror 43 is mirror-finished to form three reflecting surfaces shown in fig. 2.

Z interferometer 18Z₁，18Z₂As is clear from fig. 3, the Y interferometer 18Y is disposed at one side and the other side of the X axis direction by substantially the same distance. Also, Z interferometer 18Z₁，18Z₂Each of the interferometers is actually disposed at a position slightly lower than the Y interferometer 18Y.

As shown in fig. 2 and 3, from the Z interferometer 18Z₁，18Z₂The interferometers irradiate the distance measuring beam B1 in the Y-axis direction toward the upper reflecting surface (inclined surface) of the moving mirror 43, and irradiate the distance measuring beam B2 in the Y-axis direction toward the lower reflecting surface (inclined surface) of the moving mirror 43. In the present embodiment, the fixed mirror 47A having a reflection surface orthogonal to the distance measuring beam B1 reflected on the upper reflection surface and the fixed mirror 47B having a reflection surface orthogonal to the distance measuring beam B2 reflected on the lower reflection surface are extended in the X-axis direction at positions separated by a predetermined distance in the + Y direction from the projection unit PU in a state where the distance measuring beams B1 and B2 do not interfere with each other. The fixed mirrors 47A and 47B are supported by the same support (not shown) provided in the lens barrel holder for supporting the projection unit PU, for example.

From Z interferometer 18Z₁，18Z₂The interferometers irradiate the distance measuring beams B1, B2 in the Y-axis direction toward the movable mirror 43, and these distance measuring beams B1, B2 enter the upper and lower reflecting surfaces of the movable mirror 43 at predetermined incidence angles, are reflected on the reflecting surfaces, and enter the reflecting surfaces of the fixed mirrors 47A, 47B perpendicularly. Then, the distance measuring beams B1, B2 reflected by the reflecting surfaces of the fixed mirrors 47A, 47B pass through the same optical path in the reverse direction as that of the incident beams and return to the Z interferometer 18Z₁，18Z₂。

The Y interferometer 18Y separates a distance measuring beam B4 along a distance measuring axis in the Y axis direction from a straight line (reference axis) passing through the projection center (optical axis AX, see fig. 1) of the projection optical system PL and parallel to the Y axis toward the-X side and the + X side by the same distance, as shown in fig. 3₁，B4₂By irradiating reflection surface 17Y and receiving the respective reflected lights, detection of wafer stage WST on distance measuring beam B4 is performed with reference to the reflection surface of the Y fixing mirror fixed to the side surface of lens barrel 40 of projection unit PU₁，B4₂Position information of the irradiation point in the Y axis direction. In addition, the distance measuring beam B4 in FIG. 2₁，B4₂Representatively shown as beam B4.

The Y interferometer 18Y emits a distance measuring beam B4₁，B4₂Is between ZThe position of the central reflecting surface of movable mirror 43 (i.e., wafer stage WST) in the Y-axis direction is detected by irradiating distance measuring beam B3 toward the central reflecting surface of movable mirror 43 parallel to the XZ plane at predetermined intervals in the Y-axis direction along the distance measuring axis, and receiving distance measuring beam B3 reflected by the central reflecting surface.

Main control unit 20 measures and distance measuring beam B4 from Y interferometer 18Y₁，B4₂The average value of the measurement values of the corresponding distance measurement axes calculates displacement Δ Yo in the Y axis direction, which is the Y position of reflection surface 17Y, i.e., wafer table WTB (wafer stage WST). Further, main controller 20 calculates displacement (amount of pitch) Δ Xo of wafer stage WST in the rotational direction (θ X direction) around the X axis based on reflection surface 17Y and the Y position of the central reflection surface of movable mirror 43.

Further, main controller 20 can calculate displacements Δ Zo, Δ Yo, Δ θ Z, and Δ θ Y of wafer stage WST in the Z-axis direction, Y-axis direction, θ Z direction, and θ Y direction, based on the measurement results of Z interferometers 43A and 43B, for example, by a technique disclosed in pamphlet of international publication No. 2007/083758 (corresponding to U.S. patent application publication No. 2007/0288121).

In addition, in FIG. 1, an X interferometer 18X₁，18X₂And a Y interferometer 18Y, and a Z interferometer 18Z₁，18Z₂Representatively shown as interferometer system 18, and representatively illustrating an X fixed mirror for X-axis direction position measurement and a Y fixed mirror for Y-axis direction position measurement as fixed mirrors 57. In fig. 1, the alignment system ALG and the fixed mirror fixed thereto are omitted.

In this embodiment, a wafer X interferometer 18X₁The wafer Y interferometer 18Y is used for correction of an encoder system used in an exposure operation of a wafer, and the wafer X interferometer 18X₂Wafer Y interferometer 18Y is used for mark detection by alignment system ALG. In the present embodiment, instead of forming reflecting surfaces 17X and 17Y on the end surface of wafer table WTB, a movable mirror (plane mirror) may be fixed to an end portion of wafer stage WST.

A reference mark plate, not shown, is fixed to wafer stage WST in a state where its surface is at the same height as wafer W. On the surface of the reference mark plate, at least a pair of 1 st reference marks for reticle alignment, 2 nd reference marks for baseline measurement of an alignment system ALG having a known positional relationship with respect to the 1 st reference marks, and the like are formed.

The exposure apparatus 100 in the present embodiment further includes a pair of reticle alignment systems 13A and 13B (not shown in fig. 1, see fig. 4) arranged above the reticle stage RST at a predetermined distance in the X-axis direction. As The reticle alignment systems 13A, 13B, a ttr (through The tilt) alignment system is used which uses light of an exposure wavelength for simultaneously observing a pair of reference marks on The wafer stage WST and a pair of reticle marks on The reticle corresponding thereto via The projection optical system PL. The detailed structure of the reticle alignment system is disclosed in, for example, U.S. patent No. 5,646,413. Further, the reticle alignment system may be replaced with or used in combination with an aerial image measurement system in which a light receiving surface having a slit opening is disposed on wafer stage WST, for example. In this case, the reference mark 1 may not be provided.

Similarly, although not shown in fig. 1, the exposure apparatus 100 further includes a oblique incidence type multi-focus position detection system including an irradiation system 42a and a light receiving system 42b (see fig. 4) similar to those disclosed in, for example, U.S. Pat. No. 5,448,332.

In the exposure apparatus 100, the alignment system ALG (not shown in fig. 1, see fig. 3) is provided near the projection unit PU. As this Alignment system ALG, for example, a Field Image Alignment (FIA) system of an Image processing system is used. The alignment system ALG supplies position information of the mark with reference to the index center to the main control device 20. The main control device 20 supplies information based on the information and the distance measuring beam B4 of the wafer Y interferometer 18Y of the interferometer system 18₁，B4₂Corresponding distance measuring axis and wafer X interferometer 18X₂Measuring a mark of the test object, in particular a reference markWafer Y interferometer 18Y and wafer X interferometer 18X using fiducial mark 2 on board or alignment mark on wafer₂And (3) position information on a coordinate system (alignment coordinate system) defined by the ranging axis of (a).

Fig. 4 is a block diagram, partially omitted, showing a stage control system of the exposure apparatus 100 according to the present embodiment. The control system of fig. 6 includes a so-called microcomputer (or workstation) including a CPU (central processing unit), a ROM (Read Only Memory), a RAM (random access Memory), and the like, and is centered on a main control unit 20 which integrates the entire control unit.

In the exposure apparatus 100 configured as described above, when a wafer alignment operation is performed by a well-known EGA (enhanced full wafer alignment) method or the like disclosed in, for example, U.S. Pat. No. 4,780,617, the wafer Y interferometer 18Y and the wafer X interferometer 18X of the interferometer system 18 are used as described above₂The position of wafer stage WST in the XY plane is managed by main control device 20, and the position of wafer stage WST is managed by main control device 20 based on the measurement values of encoders 50A to 50D, during, for example, an exposure operation other than the wafer alignment operation.

Therefore, after the wafer alignment operation is completed and before the exposure is started, it is necessary to perform a switching operation of the position measurement system for measuring the position of the wafer stage in the XY plane from the wafer Y interferometer 18Y and the wafer X interferometer 18X to the position measurement system for measuring the position of the wafer stage in the XY plane₂The encoder 50A to 50D are switched. The switching operation of the position measuring system is roughly performed in the following steps.

After the wafer alignment is finished, the main control device 20 is based on the interferometers 18Y, 18X₂，18Z₁，18Z₂The measurement value (b) drives wafer stage WST in a predetermined direction, for example, the + Y direction.

Then, when wafer stage WST reaches interferometer 18X₂And the distance measuring beam from the interferometer 18X₁The distance measuring light beam irradiates the reflecting surface at the same time17X, the master control device 20 is based on the interferometer system 18 (interferometers 18Y, 18X)₂，18Z₁，18Z₂) The attitude of wafer stage WST is adjusted so that the θ z rotation (yaw) error (and θ X rotation (pitch) error and θ y rotation (roll) error) of wafer stage WST become zero, and interferometer 18X is then set₁Is preset to the interferometer 18X at that time₂The same value as the measured value of (c).

After this presetting, interferometer 18X is stopped at this position by wafer stage WST₁The short-term fluctuation of the measurement values of the axes 18Y caused by the air fluctuation (air temperature fluctuation) affects a predetermined time until the measurement values become a level negligible by the averaging effect, and the interferometer 18X acquired during the stop time is used₁The added average value of the measured values (average value in the stop time) of (B) continues as the measured values of the X linear encoders 50B, 50D, and the average value of the added average values of the measured values of the respective plurality of axes of the interferometer 18Y (average value in the stop time) taken in the stop time continues as the measured values of the Y linear encoders 50A, 50C. This ends the presetting of the X linear encoders 50B, 50D and the Y linear encoders 50A, 50C, that is, the switching operation of the position measurement system. Thereafter, main controller 20 manages the position of wafer stage WST based on the measurement values of encoders 50A to 50D.

The exposure apparatus 100 of the present embodiment performs a series of operations such as reticle alignment (including the operation of associating the reticle coordinate system and the wafer coordinate system with each other) and baseline measurement of the alignment system ALG using the reticle alignment systems 13A and 13B, the reference mark plate on the wafer stage WST, the alignment system ALG, and the like, as in a normal scanning stepper. The position control of reticle stage RST and wafer stage WST in these series of operations is performed based on the measurement values of reticle interferometer 16 and interferometer system 18.

Next, main controller 20 performs wafer replacement on wafer stage WST using a wafer loader (not shown) (when there is no wafer on wafer stage WST, wafer loading is performed), and performs wafer alignment on the wafer using alignment system ALG (e.g., EGA). By this wafer alignment, the arrangement coordinates of the plurality of irradiation regions on the wafer on the alignment coordinate system are obtained.

Thereafter, the position measurement system is switched, and the main controller 20 controls the position of the wafer stage WST based on the previously measured baseline and the measurement values of the encoders 50A to 50D, and controls the position of the reticle stage RST based on the measurement values of the reticle interferometer 16, and performs step-and-scan exposure to transfer the pattern of the reticle R to a plurality of shot areas on the wafer, respectively, in the same procedure as in a normal scanning stepper.

Fig. 5(a) is a diagram showing a state in which wafer stage WST is positioned near the center of wafer W and at a position directly below projection unit PU, and fig. 5(B) is a diagram showing a state in which wafer stage WST is positioned near the middle between the center and the outer periphery of wafer W and at a position directly below projection unit PU. Fig. 6(a) is a diagram showing a state in which wafer stage WST is positioned directly below projection unit PU in the vicinity of the + Y-side edge of wafer W, and fig. 6(B) is a diagram showing a state in which wafer stage WST is positioned directly below projection unit PU in the vicinity of the edge in a direction at 45 ° to the X axis and the Y axis when viewed from the center of wafer W. Fig. 7 is a diagram showing a state in which wafer stage WST is positioned in the vicinity of the + X-side edge of wafer W and at a position directly below projection unit PU. As can be seen from FIGS. 5(A) to 7, in any of the figures, with respect to Y read head 64 on wafer table WTB₁～64₅And Y head 64₆～64₁₀X read head 66₁～66₅And X head 66₆～66₁₀At least one (one or two in the present embodiment) of the four groups, belonging to each group, faces the corresponding scale member. Taking this fact into account, and the symmetrical arrangement of the scale members 46A to 46D in the vertical and horizontal directions about the optical axis AX of the projection optical system PL, and the Y head 64₁～64₁₀X read head 66₁～66₁₀Symmetrical arrangement of X-axis direction and Y-axis direction relative to the center of wafer carrier WSTIn exposure apparatus 100, Y head 64 can be seen even if wafer stage WST is located at any position within the movement range of wafer stage WST during exposure₁～64₅And Y head 64₆～64₁₀X read head 66₁～66₅And X head 66₆～66₁₀At least one of which faces the corresponding moving scale, the X position and the Y position of wafer stage WST can be measured by four encoders 50A to 50D at all times and substantially at the same time.

In other words, the four head clusters 64 are described above₁～64₅、64₆～64₁₀、66₁～66₅And 66₆～66₁₀Is set to have a length (e.g., head group 64)₁～64₅In the case of (1) the reading head 64₁And a reading head 64₅Distance (s)) is longer than the size (diameter) of wafer W so as to cover at least the entire range of the movement stroke (movement range) of wafer stage WST when scanning exposure is performed on the entire surface of wafer W (in the present embodiment, four head groups 64 are provided for all the irradiation regions, at least during the acceleration/deceleration and synchronization adjustment of wafer stage WST during scanning exposure and before and after scanning exposure₁～64₅、64₆～64₁₀、66₁～66₅And 66₆～66₁₀At least one of the (measuring beams) does not come off from the corresponding scale member (diffraction grating), that is, is not in a state where measurement is impossible).

Similarly, the lengths of the four scale members 46A to 46D (corresponding to the widths of the diffraction gratings) in the longitudinal direction thereof are set to be equal to or more than the movement stroke thereof, respectively, so as to cover at least the entire movement stroke of wafer stage WST during scanning exposure of the entire surface of wafer W (that is, at least during the exposure operation of wafer W, four head groups 64₁～64₅、64₆～64₁₀、66₁～66₅And 66₆～66₁₀(measuring beam) does not come off from the corresponding scale member (diffraction grating), that is, it is not in a state where measurement cannot be performed).

As described above in detail, according to exposure apparatus 100 of the present embodiment, position information of wafer stage WST in three degrees of freedom in the XY plane is calculated by encoder system 50 based on outputs of a pair of Y heads 64 facing scale members 46A and 46C, respectively, and outputs of a pair of X heads 66 facing scale members 46B and 46D, respectively, and wafer stage drive system 27 drives wafer stage WST along the XY plane based on the position information calculated by encoder system 50 based on an instruction from main control device 20. Therefore, wafer stage WST can be driven with good accuracy along the XY plane based on the measurement values of encoder system 50 over the entire range of movement of wafer stage WST without arranging a scale (grating) over the entire range of movement of wafer stage WST.

Further, according to exposure apparatus 100 of the present embodiment, when performing scanning exposure of each irradiation region on wafer W, main control apparatus 20 can drive reticle R (reticle stage RST) and wafer W (wafer stage WST) in the scanning direction (Y-axis direction) with good accuracy based on the measurement values of reticle interferometer 16 and encoders 50A, 50C (and 50B and 50D), can also drive wafer W (wafer stage WST) in the non-scanning direction (X-axis direction) with good accuracy, and can also perform high-accuracy positioning (alignment) of reticle R (reticle stage RST) and wafer W (wafer stage WST) with respect to the non-scanning direction. This enables the pattern of the reticle R to be formed with good accuracy in a plurality of irradiation regions on the wafer W.

As the encoders used in the present embodiment, various types such as the diffraction interference type and the pick-up (pick up) type can be used, and for example, a so-called scanning encoder disclosed in U.S. Pat. No. 6,639,686 and the like can be used.

Next, another embodiment of the present invention will be described with reference to FIG. 8. The exposure apparatus of this embodiment differs from the above-described embodiment only in the encoder system for the wafer stage, and this encoder system will be described below. Since the differences from fig. 3 are only in the configuration of the encoder system, the same reference numerals are given to the components having the same or equivalent functions and functions as those in fig. 3, and the description thereof will be omitted. In fig. 8, the interferometer system 18 is not shown.

As shown in fig. 8, elongated rectangular plate-like scale members 46A 'and 46B' are disposed on the-X side and the + Y side of the lowermost end portion of the projection unit PU. These scale members 46A 'and 46B' are actually fixed to the lens barrel fixing base in a suspended state by the supporting member.

The scale member 46A' is disposed on the-X side of the projection unit PU in a state where the X-axis direction is the longitudinal direction and an extended line of a center line (a center line extending in the longitudinal direction) perpendicular to the longitudinal direction is orthogonal to the optical axis of the projection optical system PL. On the surface (-Z side surface) of the scale member 46A', a reflection type diffraction grating having a predetermined pitch, for example, 1 μm, with the X-axis direction as the periodic direction is formed in the same manner as described above.

The scale member 46B 'is disposed on the + Y side of the projection unit PU such that the Y axis direction is the longitudinal direction and an extension line of a center line (a center line extending in the longitudinal direction) perpendicular to the longitudinal direction is orthogonal to an extension line of a center axis in the longitudinal direction of the scale member 46A' on the optical axis of the projection optical system PL. On the surface (-Z side surface) of the scale member 46B', a reflection type diffraction grating having a predetermined pitch, for example, 1 μm, with the Y-axis direction as the periodic direction is formed in the same manner as described above. In this case, the width of the scale member 46A ' in the direction perpendicular to the longitudinal direction (the width of the diffraction grating) is substantially the same as that of the scale member 46A, and the width of the scale member 46B ' (the width of the diffraction grating) is about twice the width of the scale member 46A ' (the width of the diffraction grating).

On the other hand, on the upper surface of wafer table WTB, Y head 64 is arranged in the above-described embodiment₆，64₇，...64₁₀At positions where X heads 66 are arranged₁，66₂，...66₅. On the upper surface of wafer table WTB, X head 66 is disposed in the above-described embodiment₁，66₂，...66₅At positions where Y heads 64 are arranged₁，64₂，...64₅。

In the present embodiment, at least two adjacent Y heads 64 are positioned within the movement range of wafer stage WST during exposure when wafer W is positioned below projection optical system PL_i、64_{i+ 1}(i-any one of 1 to 4) faces the scale member 46B' at the same time, and at least one X head 66_p(p is any one of 1 to 5) faces the scale member 46A'. That is, the Y head 64 facing the scale member 46B_i、64_i+12Y Linear encoders constituted, X head 66 opposed to scale member 46A_pThe measured values of the three encoders in total of the X linear encoders are supplied to the main controller 20. Main controller 20 performs position control of wafer stage WST by wafer stage drive system 27 based on position information of wafer stage WST in the X-axis and Y-axis directions and rotation information in the θ z direction calculated based on the measurement values of these three encoders. Thus, in a manner completely similar to the above-described embodiment, two-dimensional driving of wafer stage WST can be performed with high accuracy.

In fig. 8, the two head clusters 64 are shown₁～64₅And 66₁～66₅Is set to have a length (e.g., head group 64)₁～64₅In the case of (1) the reading head 64₁And a reading head 64₅Is longer than the size (diameter) of wafer W so as to cover at least the entire movement stroke (movement range) of wafer stage WST during the exposure operation of wafer W (in other words, each head group (measurement beam) does not come off from the corresponding movement scale (diffraction grating) during scanning exposure of all the irradiation areas, that is, it is not in a state in which measurement is impossible). In the encoder system shown in fig. 8, the length (corresponding to the range in which the diffraction grating is formed) of each of the scale members 46A 'and 46B' in the longitudinal direction thereof is set to be equal to or longer than the movement stroke thereof, so as to cover at least the entire movement stroke (movement range) of wafer stage WST during the exposure operation of wafer W (in other words, each head group (measuring beam) does not move from the corresponding scale (diffraction grating) during the scanning exposure of all the irradiation regions)) Disengaged, i.e., not in a state where measurement is impossible).

Next, another embodiment of the present invention will be described with reference to FIG. 9. Since the exposure apparatus of this embodiment is different from the above-described embodiment only in the encoder system for the wafer stage, the encoder system will be described below. Since the differences from fig. 3 are only in the configuration of the encoder system, the same reference numerals are given to the components having the same or equivalent functions and functions as those in fig. 3, and the description thereof will be omitted.

In fig. 9, a scale member 46B ″ in the form of an elongated rectangular plate is disposed on the + Y side of the lowermost end portion of the projection unit PU. This scale member 46B ″ has the same size (length and width) as the scale member 46B' described above. On the surface (-Z side surface) of the scale member 46B ″, a reflection type two-dimensional diffraction grating is formed, which is composed of a grating having a predetermined pitch of, for example, 1 μm with the Y-axis direction as the periodic direction and a grating having a predetermined pitch of, for example, 1 μm with the X-axis direction as the periodic direction.

On the upper surface of wafer table WTB, the head group 64 of FIG. 8 is used₁～64₅In the same arrangement, five two-dimensional heads (2D heads) 68 are arranged at predetermined intervals in the Y-axis direction₁～68₅. Each of the two-dimensional heads includes, for example: a pair of X-diffraction gratings and a pair of Y-diffraction gratings (fixed scale) for emitting a measuring beam in the + Z direction and condensing the measuring beam from the diffracted light of the two-dimensional diffraction grating for a predetermined number of times; an index scale (index scale) composed of a transmissive two-dimensional diffraction grating for interfering with diffracted lights respectively condensed by the pair of X diffraction gratings and the pair of Y diffraction gratings; and a detector that detects light interfered by the index scale. That is, a so-called three-diffraction interference type two-dimensional encoder head can be used as the 2D head 68₁～68₅. Instead of the 2D head, a one-dimensional head (X head) having the X-axis direction as the measurement direction and a one-dimensional head (Y head) having the Y-axis direction as the measurement direction may be used in combination. In this case, the irradiation position of the measuring beam may be different between the X head and the Y head. In addition, in this specificationThe term "two-dimensional head" is used as a concept including a combination of two one-dimensional heads such as a combination of the X head and the Y head.

In the stage device including the encoder system configured as shown in fig. 9, at least two adjacent 2D heads 68 are provided within the movement range of wafer stage WST during exposure when wafer W is positioned below projection optical system PL_i、68_i+1(i is any one of 1 to 4) faces the scale member 46B ″. That is, the 2D readhead 68 that faces the scale member 46B ″_i、68_i+1The measurement values of the two constituted two-dimensional encoders are supplied to the main control device 20. Main controller 20 performs position control of wafer stage WST by wafer stage drive system 27 based on position information of wafer stage WST in the X-axis and Y-axis directions and rotation information in the θ z direction calculated based on the measurement values of these two encoders. Thus, in a manner completely similar to the above-described embodiment, two-dimensional driving of wafer stage WST can be performed with high accuracy.

In addition, 2D head 68 may be used when it is not necessary to measure the rotation information of wafer stage WST in the θ z direction, when the rotation information in the θ z direction measured by interferometer system 18 is used, or the like₁～68₅Is opposed to the constitution of the scale member 46B ″. In this case, two scale members having two-dimensional diffraction gratings formed thereon may be provided instead of the scale member 46B ″. As described above, the size of one scale member can be suppressed and at least the entire range of movement of wafer stage WST during the exposure operation can be covered. In this case, the two scale members may be arranged such that their longitudinal directions are orthogonal to each other, or such that their longitudinal directions are the same.

In each of the above embodiments, the position of wafer stage WST is controlled using the aforementioned encoder system during the exposure operation of the wafer, but the position of wafer stage WST may be controlled using the encoder system shown in fig. 3, 8,9, and the like, for example, during the alignment operation (including at least the mark detection operation by alignment system ALG) and/or the wafer replacement operation, and the like. In this case, the switching operation of the position measuring system is not required.

Here, similarly to the case where the alignment mark on wafer W or the reference mark of wafer stage WST is detected by alignment system ALG, when the above-described encoder system (fig. 3, 8, and 9) is used, it is preferable to set the arrangement of the heads (including, for example, at least one of the position and the number) and/or the arrangement of the scale members (including, for example, at least one of the position, the number, and the size) in consideration of the movement range of wafer stage WST during this detection operation. That is, even in the detection operation of the mark performed by moving wafer stage WST to the measurement position of alignment system ALG, in order to enable position measurement with three degrees of freedom in the X-axis, Y-axis, and θ z-direction, for example, it is preferable to set the arrangement of the heads and/or the scale member so that at least three heads always face the same and/or different corresponding scale members (diffraction gratings), that is, to avoid a situation in which the position cannot be measured by the encoder system and the position control of the wafer stage is interrupted. In this case, for example, the scale member of each of the embodiments described above may be set to a size that can be used in both the exposure operation and the alignment operation, or may be provided separately from the scale member and used in the alignment operation. In particular, in the latter case, for example, the scale member may be provided in the alignment system ALG in the same arrangement as that shown in fig. 3, 8,9, and the like. Alternatively, at least one of the plurality of scale members used in the exposure operation and at least one scale member provided separately may be used, and the position of wafer stage WST may be measured by the encoder system also in the alignment operation or the like.

Further, when the reference mark of wafer stage WST is detected by the reticle alignment system and/or when the projected image of the mark of reticle R or the reference mark of reticle stage RST is detected by the aerial image measurement system, the position of wafer stage WST may be measured by the interferometer system, but it is preferable to measure the position of wafer stage WST by an encoder system including the scale member according to each of the embodiments described above.

When there is wafer stage WST at the wafer exchange position (including at least one of the loading position and the unloading position), it is preferable to set the arrangement of the heads and/or the scale members in the same manner as described above, taking into account the movement range of wafer stage WST during the wafer exchange operation, even when the above-described encoder system (fig. 3, 8, and 9) is used. That is, it is preferable to set the arrangement of the heads and/or the scale members so that the position cannot be measured by the encoder system even at the wafer exchange position, and the positional control of the wafer stage is not interrupted. The same applies to the case where the aforementioned encoder system (fig. 3, 8, and 9) is used for moving wafer stage WST between the wafer replacement position and the exposure position at which the reticle pattern is transferred via projection optical system PL, the measurement position at which the alignment system ALG detects the mark, and/or the measurement position between the alignment system ALG and the exposure position.

Further, even in a two-stage exposure apparatus that can perform an exposure operation and a measurement operation (for example, mark detection by an alignment system) substantially in parallel using two wafer stages as disclosed in, for example, U.S. Pat. No. 6,262,796, the position of each wafer stage can be controlled using the encoder system (fig. 3, 8, and 9) in which a head is provided on each wafer stage, as in the above embodiments. Here, the position of each wafer stage can be measured by the encoder system by appropriately setting the arrangement of the heads and/or the scale members as described above not only in the exposure operation but also in other operations such as the measurement operation. For example, the position of each wafer stage can be controlled by using the scale member of each of the above embodiments as it is by appropriately setting the arrangement of the heads, but the scale member that can be used in the measurement operation may be provided separately from the scale member. In this case, for example, four scale members having the same arrangement as the scale members of the above embodiments, for example, arranged in a cross shape with the alignment system ALG as the center, may be provided, and the position information of each wafer stage WST may be measured by these scale members and the corresponding heads during the above measurement operation. In the exposure apparatus of the dual-wafer stage system, for example, the heads (fig. 3, 8, and 9) are provided in the same arrangement as described above, and when the exposure operation of the wafer mounted on one wafer stage is completed, the other wafer stage on which the next wafer having been subjected to mark detection or the like at the measurement position is mounted is arranged at the exposure position by being replaced with the one wafer stage. The measurement operation performed in parallel with the exposure operation is not limited to the detection of the mark on the wafer or the like by the alignment system, and the detection of the surface information (step information or the like) of the wafer may be performed instead of or in combination with this method.

In the above description, when the position control of the wafer stage using the encoder system is interrupted in the measurement position or the replacement position or in the process of moving the wafer stage from one position of the exposure position, the measurement position, and the replacement position to the other position, it is preferable to perform the position control of the wafer stage at each position or in the process of moving using a measurement device (e.g., an interferometer, an encoder, or the like) different from the encoder system.

In the above embodiments, as disclosed in, for example, pamphlet of international publication No. 2005/074014 (corresponding to U.S. patent application publication No. 2007/0127006), a measurement stage may be provided separately from the wafer stage, and the measurement stage may be arranged directly below the projection optical system PL by replacement with the wafer stage at the time of a wafer replacement operation or the like, so as to measure characteristics of the exposure apparatus (for example, imaging characteristics (wavefront aberration) of the projection optical system, polarization characteristics of the illumination light IL, and the like). In this case, the head may be arranged on the measurement stage, and the position of the measurement stage may be controlled using the scale member. In the exposure operation of the wafer mounted on the wafer stage, the measurement stage is moved between the retreated position and the exposure position by being retreated to a predetermined position where the measurement stage does not interfere with the wafer stage. Therefore, even during the period when the retreating position or the exposure position is moved from one of the retreating position and the exposure position to the other, it is preferable to set the arrangement of the head and/or the scale member so as to avoid the occurrence of a situation in which the position cannot be measured by the encoder system and the positional control of the measurement stage is interrupted, in the same manner as in the case of the wafer stage, in consideration of the movement range of the measurement stage. Alternatively, when the position control of the measurement stage by the encoder system is interrupted at the retreated position or during the movement, the position control of the measurement stage is preferably performed by using a measurement device (e.g., an interferometer, an encoder, or the like) different from the encoder system. Alternatively, the position of the measurement stage may be controlled only by the interferometer system.

In each of the above embodiments, for example, the distance between the pair of scale members extending in the same direction must be increased depending on the size of the projection unit PU, and thus, when scanning exposure is performed on a specific irradiation region on the wafer W, for example, an irradiation region located at the outermost periphery, the head corresponding to one of the pair of scale members may not face the other. For example, when the projection unit PU is slightly enlarged in fig. 3, neither of the corresponding X heads 66 can face the scale member 46B of the pair of scale members 46B, 46D. Further, in a liquid immersion type exposure apparatus in which a space between the projection optical system PL and the wafer is filled with a liquid (for example, pure water) as disclosed in, for example, WO99/49504 pamphlet, etc., a nozzle member or the like for supplying the liquid is provided so as to surround the projection unit PU, and therefore it is more difficult to dispose the head close to the exposure region of the projection optical system PL. Therefore, when the encoder system of fig. 3 is used in the liquid immersion type exposure apparatus, the encoder system need not be configured to be able to always measure two pieces of positional information in each of the X-axis and Y-axis directions, but may be configured to be able to measure two pieces of positional information in one of the X-axis and Y-axis directions and one piece of positional information in the other. That is, when the position of the wafer stage (or the measurement stage) is controlled by the encoder system, it is not necessary to use two pieces of positional information in the X-axis direction and the Y-axis direction, or four pieces of positional information in total.

In each of the above embodiments, the configuration of the interferometer system 18 is not limited to fig. 3, and the wafer X interferometer 18X may not be provided, for example, when a scale member is disposed in the alignment system ALG (measurement position)₂The wafer X interferometer 18X₂For example with a waferY interferometer 18Y is similarly configured as a multi-axis interferometer, and is configured to measure not only the X position of wafer stage WST but also rotation information (e.g., yaw and roll). In each of the above embodiments, the interferometer system 18 is used for the purpose of performing calibration of the encoder system or the position measurement of the wafer stage in an operation other than the exposure operation, but the present invention is not limited to this, and the encoder system 50 and the interferometer system 18 may be used in combination in at least one of the exposure operation, the measurement operation (including the alignment operation), and the like. For example, when encoder system 50 is unable to measure or its measurements are abnormal, interferometer system 18 may be switched on to continue position control of wafer stage WST. In the above embodiments, the interferometer system 18 may not be provided, and only the encoder system may be provided.

In each of the above embodiments, the position of wafer stage WST in at least one of the X axis and the Y axis is measured by encoder system 50, but the present invention is not limited to this, and position measurement in the Z axis direction may be performed. For example, an encoder type head capable of measuring a position in the Z-axis direction may be provided on the wafer stage independently of the heads, or the heads may be heads capable of measuring a position in at least one of the X-axis direction and the Y-axis direction and a position in the Z-axis direction.

In the encoder system shown in fig. 3 and 8, at least one of the X head and the Y head may be replaced with a 2D head, and the scale member facing the 2D head may be a scale member on which a two-dimensional diffraction grating is formed. In this case, in the encoder system shown in fig. 3, the number of scale members can be reduced from four to two, and in the encoder system shown in fig. 8, the width can be reduced by making the scale member 46B' a scale member in which a two-dimensional diffraction grating is formed.

In the embodiments described above, a plurality of measuring beams can be always applied to one scale member, and when one measuring beam is abnormal, the measurement can be continued by switching to another measuring beam. In this case, the plurality of measuring beams may be irradiated from one head to the scale member, or may be irradiated from a plurality of different heads. When a plurality of measuring beams are irradiated to one scale member, the plurality of measuring beams are preferably irradiated to different positions on the scale member.

Each of the scale members may be configured by integrally holding a plurality of small scale members on a plate member or the like. In this case, when the head facing the connection portion between the small scale members cannot measure or measures an abnormality, the position measurement by another head facing a portion other than the connection portion may be used instead.

The arrangement of the heads described in the above embodiments is merely an example, and the arrangement of the heads is not limited thereto.

In the embodiments described above, the scale member is fixed to the lens barrel fixing base in a suspended state by the support member, but the scale member may be held by a holding member other than the lens barrel fixing base. In the above embodiments, the temperature of the scale member may be adjusted as necessary.

In each of the above embodiments, there is no need to dispose a scale (grating) corresponding to the entire range of movement of wafer stage WST, and therefore, there is an advantage that air conditioning and the like can be easily performed.

In the above embodiments, the present invention has been described as being applied to a scanning stepper, but the present invention is not limited to this, and may be applied to a stationary exposure apparatus such as a stepper. Even in a stepper or the like, by measuring the position of the stage on which the object to be exposed is mounted by the encoder, unlike the case where the position of the stage is measured by using an interferometer, it is possible to make the occurrence of a position measurement error due to air shake almost zero, and to position the stage with high accuracy from the measurement value of the encoder, and as a result, it is possible to transfer the pattern of the reticle to the object with high accuracy. The present invention can also be applied to a reduction projection exposure apparatus of a step-by-step bonding method in which an irradiation region and an irradiation region are combined.

The projection optical system in the exposure apparatus according to each of the above embodiments may be not only a reduction system but also an equi-magnification system or an enlargement system, and the projection optical system PL may be not only a refraction system but also a reflection system or a catadioptric system, and the projection image may be an inverted image or an erect image.

The illumination light IL is not limited to ArF excimer laser beam (wavelength 193nm), but may be ultraviolet light such as KrF excimer laser beam (wavelength 248nm), or F₂Vacuum ultraviolet light such as laser beam (wavelength 157 nm). As the vacuum ultraviolet light, a harmonic wave disclosed in the specification of U.S. patent No. 7,023,610, which is obtained by amplifying a single-wavelength laser beam in an infrared region or a visible region oscillated from a DFB semiconductor laser or a fiber laser by an optical fiber amplifier coated with erbium (or both erbium and ytterbium), and converting the wavelength into ultraviolet light by a nonlinear optical crystal, can be used.

In the above embodiments, the illumination light IL for the exposure apparatus is not limited to light having a wavelength of more than 100nm, and light having a wavelength of less than 100nm may be used. For example, the present invention can be applied to an EUV exposure apparatus using EUV (Extreme UltraViolet) light in a soft X-ray region (for example, a wavelength region of 5 to 15 nm). The present invention is also applicable to an exposure apparatus using a charged particle beam such as an electron beam or an ion beam.

In the above embodiments, a light transmissive mask (reticle) in which a predetermined light shielding pattern (or phase pattern, or dimming pattern) is formed on a light transmissive substrate is used, but an electronic mask (also referred to as a variable shape mask, an active mask, or an image generator, for example, a DMD (Digital Micro-mirror Device) including one type of non-light emitting type image display elements (spatial light modulators) or the like) in which a transmission pattern, a reflection pattern, or a light emitting pattern is formed based on electronic data of a pattern to be exposed, for example, as disclosed in U.S. Pat. No. 6,778,257, may be used instead of the reticle. When the variable shape mask is used, since a stage on which a wafer, a glass plate, or the like is mounted scans the variable shape mask, the same effects as those of the above embodiments can be obtained by measuring the position of the stage using an encoder.

The present invention is also applicable to an exposure apparatus (lithography system) that forms an interference pattern on a wafer W to form a line and space pattern on the wafer W, as disclosed in, for example, pamphlet of international publication No. 2001/035168.

Further, for example, the present invention can be applied to an exposure apparatus disclosed in, for example, U.S. Pat. No. 6,611,316, in which two reticle patterns are combined on a wafer by a projection optical system, and double exposure is performed substantially simultaneously on one irradiation region on the wafer by one scanning exposure.

The apparatus for forming a pattern on an object is not limited to the exposure apparatus (lithography system), and the present invention can be applied to an apparatus for forming a pattern on an object by an inkjet method, for example.

In the above embodiment, the object to be patterned (the object to be exposed to the energy beam) is not limited to the wafer, and may be another object such as a glass plate, a ceramic substrate, a film member, or a mask blank.

The use of the exposure apparatus is not limited to the exposure apparatus for semiconductor manufacturing, and the exposure apparatus can be widely applied to, for example, a liquid crystal exposure apparatus for transferring a liquid crystal display element pattern onto a square glass plate, or an exposure apparatus for manufacturing an organic EL, a thin film magnetic head, an imaging element (such as a CCD), a micromachine, a DNA chip, or the like. In addition to the production of microdevices such as semiconductor devices, the present invention can be applied to an exposure apparatus for transferring a circuit pattern onto a glass substrate, a silicon wafer, or the like in order to produce a reticle or a mask used in a light exposure apparatus, an EUV (extreme ultraviolet) exposure apparatus, an X-ray exposure apparatus, an electron beam exposure apparatus, or the like.

The moving body driving device of the present invention is not limited to the exposure device, and can be widely applied to other substrate processing devices (for example, other devices such as a laser repair device and a substrate inspection device), and devices having a moving stage such as a sample positioning device and a wire bonding device in other precision machines.

Further, the disclosures of all publications, international pamphlets, U.S. patent application publications, and U.S. patent specifications relating to exposure apparatuses and the like cited in the description so far are incorporated as a part of the description of the present specification.

Further, the semiconductor device is manufactured through the steps of: a step of designing the function and performance of the device, a step of fabricating a reticle based on this designing step, a step of fabricating a wafer from a silicon material, a photolithography step of transferring a pattern formed on a mask onto an object such as a wafer by the exposure apparatus of each of the above embodiments in which the transfer characteristics of the pattern have been adjusted by the above-described adjustment method, a development step of developing the exposed wafer, an etching step of removing exposed members other than the remaining portions of the resist by etching, a resist removal step of removing the unnecessary resist after the completion of etching, a device assembling step (including a dicing step, a bonding step, a packaging step), an inspection step, and the like. In this case, since the exposure apparatus according to each of the above embodiments is used in the photolithography step, a device with high integration can be manufactured with high yield.

Industrial applicability

As described above, the moving body drive system of the present invention is suitable for driving a moving body along a predetermined plane. The pattern forming apparatus of the present invention is suitable for forming a pattern on an object such as a wafer. The exposure apparatus, the exposure method, and the device manufacturing method according to the present invention are suitable for manufacturing electronic devices such as semiconductor devices.

Claims (31)

1. A moving body drive system for driving a moving body substantially along a predetermined plane, comprising:

a 1 st scale arranged on a 1 st surface parallel to the predetermined plane and facing the movable body with a 1 st direction as a longitudinal direction, the 1 st scale having a 1 st grating with a period direction of the 1 st direction or a 2 nd direction perpendicular to the 1 st direction;

a 2 nd scale arranged on the 1 st surface with the 2 nd direction as a longitudinal direction, and having a 2 nd grating having a periodic direction orthogonal to the 1 st grating;

a measurement system having: a 1 st head group including a plurality of 1 st heads which are arranged on a 2 nd surface of the movable body substantially parallel to the predetermined plane at different positions in the 2 nd direction and have a periodic direction of the 1 st grating as a measurement direction; and a 2 nd head group including a plurality of 2 nd heads which are disposed on the 2 nd surface of the movable body at positions different in the 1 st direction and have a periodic direction of the 2 nd grating as a measurement direction, the measurement system calculating position information of the movable body in at least two degrees of freedom directions in the predetermined plane including the 1 st and 2 nd directions, based on an output of the 1 st head facing the 1 st scale and an output of the 2 nd head facing the 2 nd scale; and

and a drive system for driving the movable body along the predetermined plane based on the position information calculated by the measurement system.

2. The movable body drive system according to claim 1, wherein the 1 st scale has the 2 nd direction width in which three of the 1 st heads can simultaneously oppose;

the measurement system calculates positional information of the movable body in three degrees of freedom in the predetermined plane based on outputs of at least two 1 st heads facing the 1 st scale and outputs of the 2 nd head facing the 2 nd scale at the same time.

3. The movable body drive system according to claim 1, wherein a pair of the 1 st scale is arranged on the 1 st surface with a predetermined interval in a longitudinal direction toward the 1 st direction;

the 1 st head group is disposed on the 2 nd surface of the movable body in such a manner that at least one 1 st head can simultaneously face each scale of the pair of 1 st scales when the movable body is located within the predetermined effective region;

the measurement system calculates position information of the movable body in three degrees of freedom in the predetermined plane based on outputs of the two 1 st heads facing each scale of the pair of 1 st scales and an output of the 2 nd head facing the 2 nd scale at the same time.

4. The movable body drive system according to claim 1, wherein a pair of the 2 nd scale is arranged on the 1 st surface with a predetermined interval in a longitudinal direction toward the 2 nd direction;

the 2 nd head group is disposed on the 2 nd surface of the movable body in such a manner that at least one of the 2 nd heads can simultaneously face each of the pair of 2 nd scales when the movable body is located within the effective region;

the measurement system calculates position information of the movable body in three degrees of freedom in the predetermined plane based on outputs of the two 1 st heads simultaneously facing the respective scales of the pair of 1 st scales and outputs of the two 2 nd heads simultaneously facing the respective scales of the pair of 2 nd scales.

5. A moving body drive system for driving a moving body substantially along a predetermined plane, comprising:

a scale which is arranged on a 1 st surface parallel to the predetermined plane and opposed to the movable body with a 1 st direction as a longitudinal direction and on which a two-dimensional grating having a periodic direction of the 1 st direction and a 2 nd direction perpendicular to the 1 st direction is formed;

a measurement system including a plurality of two-dimensional heads which are disposed on a 2 nd surface of the movable body substantially parallel to the predetermined plane at positions different in the 2 nd direction and have the 1 st and 2 nd directions as measurement directions, and which calculates position information of the movable body in at least two degrees of freedom directions in the predetermined plane including the 1 st and 2 nd directions from outputs of the two-dimensional heads which face the scale; and

and a drive system for driving the movable body along the predetermined plane based on the position information calculated by the measurement system.

6. The movable body drive system according to claim 5, wherein the scale has a width in the 2 nd direction in which three of the two-dimensional heads can simultaneously oppose;

the measurement system calculates positional information of the movable body in three degrees of freedom in the predetermined plane based on outputs of at least two-dimensional heads simultaneously facing the scale.

7. The moving body drive system according to any one of claims 1 to 6, wherein the drive system includes a planar motor that drives the moving body along the predetermined plane.

8. A pattern forming apparatus for forming a pattern on an object, comprising:

a patterning device for generating a pattern on the object; and

the moving body drive system according to any one of claims 1 to 7,

the moving body driving system drives the moving body on which the object is mounted in order to form the pattern on the object.

9. The pattern forming apparatus according to claim 8, wherein the object has a sensitive layer, and the patterning device forms a pattern on the object by exposing the sensitive layer to the irradiation of the energy beam.

10. An exposure apparatus for forming a pattern on an object by irradiation with an energy beam, comprising:

a patterning device configured to irradiate the object with the energy beam; and

the moving body drive system according to any one of claims 1 to 7,

the movable body drive system drives a movable body on which the object is mounted so as to move the energy beam and the object relative to each other.

11. An exposure apparatus for exposing an object with an energy beam, comprising:

a movable body capable of holding the object to move along a predetermined plane;

a scale substantially parallel to the predetermined plane and arranged with the 1 st direction as a longitudinal direction; and

and an encoder system that includes a plurality of heads provided on the movable body and having different positions in a 2 nd direction orthogonal to the 1 st direction in the predetermined plane, and that measures positional information of the movable body with at least one of the plurality of heads facing the scale at least at the time of exposure of the object.

12. The exposure apparatus according to claim 11, further comprising:

a projection system for projecting the energy beam onto the object; and

a holding member that holds the projection system,

the scale is suspended and supported by the holding member.

13. The exposure apparatus according to claim 11 or 12, wherein the plurality of heads are capable of measuring positional information of the movable body in two different directions, respectively.

14. The exposure apparatus according to any one of claims 11 to 13,

the plurality of the scaleplates are arranged;

in the encoder system, the plurality of heads are provided on the movable body so as to correspond to the plurality of scales, respectively.

15. The exposure apparatus according to any one of claims 11, 13, and 14, further comprising:

a projection system for projecting the energy beam onto the object; and

a mark detection system capable of detecting a mark of the object,

the encoder system may measure position information of the movable body at the time of detection of the mark.

16. The exposure apparatus according to claim 15,

the scale is disposed in proximity to the projection system, and a scale different from the scale is disposed in proximity to the mark detection system.

17. A device manufacturing method, comprising:

an act of exposing the object using the exposure apparatus according to any one of claims 10 to 16; and

and developing the exposed object.

18. An exposure method for exposing an object with an energy beam, comprising:

an operation of holding the object by a movable body; and

an operation of exposing the object with the energy beam by driving the movable body by the movable body driving system according to any one of claims 1 to 7.

19. An exposure method for exposing an object held by a movable body that moves substantially along a predetermined plane to an energy beam, characterized in that:

a 1 st scale having a 1 st direction as a longitudinal direction and a 1 st grating having a periodic direction in the 1 st direction or a 2 nd direction perpendicular to the 1 st direction, and a 2 nd scale having a 2 nd grating having a periodic direction orthogonal to the 1 st grating, the periodic direction being a longitudinal direction, are arranged on a 1 st surface parallel to the predetermined plane, which is opposed to the movable body; and comprises:

a measurement step of calculating position information of the movable body in at least two degrees of freedom directions in the predetermined plane including the 1 st and 2 nd directions, based on an output of the 1 st head facing the 1 st scale and an output of the 2 nd head facing the 2 nd scale, from among a 1 st head group including a plurality of 1 st heads and a 2 nd head group including a plurality of 2 nd heads, the plurality of 1 st heads being disposed on a 2 nd surface of the movable body substantially parallel to the predetermined plane with a position of the 2 nd direction being different and having a periodic direction of the 1 st grating as a measurement direction, the plurality of 2 nd heads being disposed on the 2 nd surface of the movable body with a position of the 1 st direction being different and having a periodic direction of the 2 nd grating as a measurement direction; and

and a driving step of driving the movable body along the predetermined plane based on the position information calculated in the measuring step.

20. The exposure method according to claim 19,

the 1 st scale has a width in the 2 nd direction which three 1 st heads can simultaneously face;

in the measuring step, position information of the movable body in three degrees of freedom in the predetermined plane is calculated based on outputs of at least two 1 st heads facing the 1 st scale and outputs of the 2 nd head facing the 2 nd scale at the same time.

21. The exposure method according to claim 19,

a pair of the 1 st scale plates arranged on the 1 st surface with a predetermined interval in a longitudinal direction toward the 1 st direction;

the 1 st head group is disposed on the 2 nd surface of the movable body in such a manner that at least one 1 st head can simultaneously face each scale of the pair of 1 st scales when the movable body is located within the predetermined effective region;

in the measuring step, position information of the movable body in three degrees of freedom in the predetermined plane is calculated based on outputs of the two 1 st heads simultaneously facing each scale of the pair of 1 st scales and an output of the 2 nd head facing the 2 nd scale.

22. The exposure method according to claim 19,

a pair of the 2 nd scale plates arranged on the 1 st surface with a predetermined interval in a longitudinal direction toward the 2 nd direction;

the 2 nd head group is disposed on the 2 nd surface of the movable body in such a manner that at least one of the 2 nd heads can simultaneously face each of the pair of 2 nd scales when the movable body is located within the effective region;

in the measuring step, position information of the movable body in three degrees of freedom in the predetermined plane is calculated based on outputs of the two 1 st heads simultaneously facing the respective scales of the pair of 1 st scales and outputs of the two 2 nd heads simultaneously facing the respective scales of the pair of 2 nd scales.

23. An exposure method for exposing an object held by a movable body that moves substantially along a predetermined plane to an energy beam, characterized in that:

a scale on which a 1 st direction is a longitudinal direction and a two-dimensional grating having a periodic direction of the 1 st direction and a 2 nd direction perpendicular to the 1 st direction is formed is disposed on a 1 st surface parallel to the predetermined plane, the 1 st surface facing the movable body,

the method comprises the following steps:

a measurement step of calculating position information of the movable body in at least two degrees of freedom directions within the predetermined plane including the 1 st and 2 nd directions, based on outputs of two-dimensional heads opposed to the scale, the two-dimensional heads being arranged on a 2 nd surface of the movable body substantially parallel to the predetermined plane at different positions in the 2 nd direction and having the 1 st and 2 nd directions as measurement directions; and

and a driving step of driving the movable body along the predetermined plane based on the position information calculated in the measuring step.

24. The exposure method according to claim 23,

the scale has a width in the 2 nd direction in which the three two-dimensional heads can simultaneously face each other;

in the measuring step, position information of the movable body in three degrees of freedom in the predetermined plane is calculated based on outputs of at least two-dimensional heads simultaneously facing the scale.

25. An exposure method for exposing an object held by a movable body movable along a predetermined plane to an energy beam, comprising:

an encoder system including a plurality of heads provided on the movable body and having different positions in a 2 nd direction orthogonal to the 1 st direction in the predetermined plane is used, and positional information of the movable body is measured at least at the time of exposure of the object by at least one of the plurality of heads that is substantially parallel to the predetermined plane and faces a scale arranged with the 1 st direction as a longitudinal direction.

26. The exposure method according to claim 25, wherein,

the scale is suspended and supported by a holding member, and the holding member holds a projection system that projects the energy beam onto the object.

27. The exposure method according to claim 25 or 26,

as each of the plurality of heads, a head capable of measuring position information of the movable body in two different directions is used.

28. The exposure method according to any one of claims 25 to 27,

the plurality of the scaleplates are arranged;

the plurality of heads are provided on the movable body corresponding to the plurality of scales, respectively.

29. The exposure method according to any one of claims 25 to 28,

the encoder system may measure position information of the movable body when the mark of the object is detected by the mark detection system.

30. The exposure method according to claim 29, wherein,

the scale is disposed in proximity to a projection system that projects the energy beam onto the object, and a scale different from the scale is disposed in proximity to the mark detection system.

31. A device manufacturing method, comprising:

an act of exposing the object using the exposure method according to any one of claims 19 to 30; and

and developing the exposed object.