JP2013201801A - Planar motor, exposure device, and device manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit the heat generation of an armature coil.SOLUTION: A planar motor includes: a movable element 52 including first and second magnet units which are provided at a movable body WST moving in two directions, i.e., X and Y directions that are perpendicular to each other on a base 21; a first coil unit 60X including multiple pairs of first coils 38X arranged in the base so as to face the first magnet unit and applying a driving force to the first magnet unit in the X direction; a second coil unit 60Y including multiple pairs of second coils 38Y that are arranged in the base facing the movable body across the first coil unit and applying a driving force to the second magnetic unit in the Y direction. Thicknesses are different between the first coil unit 60X and the second coil unit 60Y.

Description

  The present invention relates to a planar motor, an exposure apparatus, and a device manufacturing method, and more particularly to a planar motor that drives a moving body two-dimensionally on a base, an exposure apparatus that includes the planar motor, and a device manufacturing method that uses the exposure apparatus. .

  Conventionally, various exposure apparatuses are used in a lithography process for manufacturing electronic devices (microdevices) such as semiconductor elements and liquid crystal display elements. For example, as an exposure apparatus used for manufacturing a semiconductor element, a step-and-repeat reduction projection exposure apparatus (so-called stepper), a step-and-scan reduction projection exposure apparatus (so-called scanning stepper (also called a scanner)). Etc. are mainly used. In this type of exposure apparatus, the pattern of the reticle is projected by projecting illumination light onto a wafer (or glass plate or the like) coated with a sensitive agent (resist) via a reticle (or mask) and a projection optical system. (Reduced image) is transferred onto the wafer.

  However, as the wafer size increases, the wafer stage becomes larger, and it is said that a planar motor is promising as a driving source for the wafer stage in the future. As the planar motor, for example, an electromagnetic force (Lorentz force) drive type two-dimensional linear actuator (see, for example, Patent Document 1) in which a linear motor is developed in a two-dimensional direction, or an electric machine arranged in one direction in a two-dimensional direction. A planar motor having a structure in which a child coil and armature coils arranged in the other direction are stacked is known (for example, see Patent Documents 2 and 3).

  However, when a large current is passed through the coil unit (the armature coil included in the coil unit) in order to obtain a large driving force, heat generation of the coil unit becomes a problem. The heat generated by the coil unit causes, for example, a decrease in energy efficiency of the planar motor, burning of the planar motor, and temperature fluctuation of the air around the wafer stage (so-called air fluctuation). It also causes measurement errors in the measurement system.

US Pat. No. 5,196,745 US Pat. No. 6,445,093 US Pat. No. 6,452,292

  According to the first aspect of the present invention, a mover having first and second magnet units each including a magnet provided on a movable body movable in first and second directions orthogonal to each other on the base; A plurality of sets of first coils arranged in the base so as to face the mover, and at least one layer of a first coil unit that applies a driving force in the first direction to the mover; A second set of at least one layer that includes a plurality of sets of second coils arranged in the base so as to face the mover across one coil unit, and applies a driving force in the second direction to the mover. A planar motor comprising a stator having a coil unit, wherein the at least one first coil unit and the at least one second coil unit have different thicknesses is provided.

  According to this, the thickness of the first coil unit of at least one layer is different from the thickness of the second coil unit of at least one layer. For this reason, for example, it is possible to set the thicknesses of the first and second coil units so that the total calorific value is reduced, for example, by performing experiments with various changes in both dimensions. Thus, the heat generation of the first and second coil units and the decrease in efficiency (energy loss) of the planar motor due to the heat generation can be suppressed, the temperature rise is suppressed, and the coil unit (planar motor) is prevented from being burned out. be able to.

  According to a second aspect of the present invention, there is provided an exposure apparatus that exposes an object with an energy beam, the planar motor that drives the movable body that holds the object in the first and second directions, and the energy. There is provided a first exposure apparatus comprising: a pattern generation device that irradiates a beam on the object to generate a pattern on the object.

  According to this, since the temperature rise of the planar motor can be suppressed, air fluctuation around the moving body on the base can be suppressed, and the positioning accuracy of the moving body (object) can be improved.

  According to a third aspect of the present invention, there is provided an exposure apparatus that exposes an object with an energy beam to form patterns in a plurality of partitioned areas on the object, wherein the moving body that holds the object is the first apparatus. And the plane motor driven in the second direction, and a pattern generation device that irradiates the energy beam onto the object driven in the second direction and generates the pattern in each of a plurality of partitioned regions on the object A second exposure apparatus is provided.

  According to this, the first coil unit for generating the first direction driving force that requires a larger driving force (acceleration, thrust) than the driving in the second direction (scanning direction) is used for generating the second direction driving force. Since it is arranged closer to the mover than the second coil unit, the first coil unit (and the second coil unit) can generate heat more than necessary, and the moving body can be driven efficiently. It becomes possible. Thereby, it becomes possible to form a pattern in a plurality of partitioned regions on the object with high throughput.

  According to a fourth aspect of the present invention, there is provided a device comprising: forming a pattern on an object using the first or second exposure apparatus; and developing the object on which the pattern has been formed. A manufacturing method is provided.

It is a figure which shows schematically the structure of exposure apparatus. It is a top view which shows a substrate stage apparatus. It is a figure which shows a wafer stage with a stage base. 4A is a plan view schematically showing the stage base from which the ceramic plate has been removed together with the mover, and a diagram showing the arrangement of the armature coils 38X. FIG. 4B is a plan view from FIG. It is a top view which shows the stage base of the state which removed the X coil unit 60X schematically with a needle | mover, and is a figure which shows the arrangement | sequence of the armature coil 38Y. FIG. 5A is a diagram showing the relationship between the Y coil thickness and the coil thickness (the sum of the thicknesses of the X coil unit and the Y coil unit) and the amount of heat generated for each of the X coil thicknesses of 4 to 10 mm. FIG. 5B shows the relationship between the Y coil thickness and its thermal conductivity. FIG. 2 is a block diagram showing a main configuration of a control system of the exposure apparatus in FIG. 1.

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

  FIG. 1 schematically shows a configuration of an exposure apparatus 100 according to an embodiment. The exposure apparatus 100 is a step-and-scan type scanning exposure apparatus, that is, a so-called scanner. As will be described later, in the present embodiment, a projection optical system PL is provided, and in the following, the direction parallel to the optical axis AX of the projection optical system PL is the Z-axis direction, and the reticle is in a plane perpendicular to the Z-axis direction. The direction in which the wafer and the wafer are relatively scanned is the Y-axis direction, the direction orthogonal to the Z-axis and the Y-axis is the X-axis direction, and the rotation (tilt) directions around the X-axis, Y-axis, and Z-axis are θx and θy, respectively. , And θz direction will be described.

  The exposure apparatus 100 holds a reticle R illuminated by an illumination system 10 and exposure illumination light (hereinafter abbreviated as illumination light) IL from the illumination system 10 and holds a predetermined scanning direction (here, in FIG. 1). It includes a reticle stage RST that moves in the left-right direction in the paper plane), a projection optical system PL that projects illumination light IL emitted from the reticle R onto the wafer W, and a wafer stage WST on which the wafer W is placed. A stage device 30 and a control system thereof are provided.

  The illumination system 10 includes a light source, an illuminance uniformizing optical system including an optical integrator, a reticle blind, and the like (both not shown) as disclosed in, for example, US Patent Application Publication No. 2003/0025890. And an illumination optical system. The illumination system 10 illuminates a slit-shaped illumination area IAR on the reticle R set (limited) with a reticle blind (also called a masking system) with illumination light (exposure light) IL with substantially uniform illuminance. Here, as an example of the illumination light IL, ArF excimer laser light (wavelength 193 nm) is used.

  On reticle stage RST, reticle R on which a circuit pattern or the like is formed on its pattern surface (the lower surface in FIG. 1) is fixed, for example, by vacuum suction. The reticle stage RST can be finely driven in the XY plane by a reticle stage drive system 11 (not shown in FIG. 1, see FIG. 6) including a linear motor, for example, and has a predetermined scanning direction (here in FIG. 1). It can be driven at a scanning speed specified in the Y-axis direction which is the horizontal direction in the drawing.

  Position information of reticle stage RST in the XY plane (including rotation information in the θz direction) is transferred by reticle laser interferometer (hereinafter referred to as “reticle interferometer”) 16 to movable mirror 15 (actually in the Y-axis direction). Through a Y-moving mirror (or retro reflector) having an orthogonal reflecting surface and an X moving mirror having a reflecting surface orthogonal to the X-axis direction), detection is always performed with a resolution of, for example, about 0.25 nm. Is done. The measurement value of reticle interferometer 16 is sent to main controller 20 (not shown in FIG. 1, refer to FIG. 6), and main controller 20 controls reticle stage drive system 11 based on the measurement value of reticle interferometer 16. The position (and speed) of the reticle stage RST in the X-axis direction, Y-axis direction, and θz direction is controlled.

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

  As shown in FIG. 1, the stage apparatus 30 includes a base board 12, a stage base 21 arranged on the base board 12, and a wafer stage WST arranged on the stage base 21. Stage device 30 further includes a wafer laser interferometer (hereinafter referred to as “wafer interferometer”) 31 (see FIG. 6) for measuring the position of wafer stage WST, and wafer stage drive system 50 (FIG. 6) for driving wafer stage WST. For example).

  The base board 12 is supported substantially horizontally (parallel to the XY plane) on the floor surface F via an anti-vibration mechanism (not shown).

  The stage base 21 is supported on the base board 12 in a non-contact manner via an air bearing (not shown). A stator described later is accommodated in the upper portion of the stage base 21. In the present embodiment, when the wafer stage WST described later is driven, the stage base 21 receives a reaction force of the driving force and moves according to the momentum conservation law, thereby canceling the reaction force (counter). (Also called mass). Therefore, a trim motor that drives the stage base 21 may be provided between the stage base 21 and the base board 12 so that the amount of movement of the stage base 21 from the reference position is within a predetermined range. The configuration of the stage base 21 will be further described later.

  FIG. 2 shows a plan view of wafer stage WST. As shown in FIGS. 1 and 2, wafer stage WST includes wafer stage main body 51, three support mechanisms 32 a, 32 b, 32 c provided on wafer stage main body 51, and wafer table 18.

  In FIG. 3, wafer stage WST is shown together with stage base 21. In FIG. 3, for convenience of the following description, it is shown in a sectional view. As shown in FIG. 3, the wafer stage main body 51 is formed of a rectangular parallelepiped member having a recess at the bottom, and a mover 52 configured by a magnet unit described later is accommodated in the recess. Around the lower end portion of the wafer stage main body 51, an air slider 57, which is a kind of a hydrostatic bearing device, whose bottom surface is set at the same position as the bottom surface of the mover 52 or slightly pulled is fixed. Wafer stage WST is levitated and supported by air slider 57 on the upper surface of stage base 21 through a gap (clearance, gap) of about several μm, for example.

  The three support mechanisms 32a, 32b, and 32c each include a voice coil motor or the like, and are arranged at the positions of the apexes of the equilateral triangle in plan view on the wafer stage main body 51. The three support mechanisms 32a, 32b, and 32c support the wafer table 18 from below and individually drive it in the Z-axis direction. The wafer table 18 is finely driven in each of the Z-axis, θx, and θy directions by three support mechanisms 32a, 32b, and 32c. The support mechanisms 32a to 32c are individually controlled by the main controller 20 (see FIG. 6).

  Returning to FIG. 1, the wafer W is fixed on the wafer table 18 by, for example, vacuum suction. A movable mirror 27 that reflects the laser beam from the wafer interferometer 31 is fixed on the wafer table 18. The wafer interferometer 31 allows the wafer table 18 to move in six directions of freedom (X axis, Y axis, Z axis). , Θx, θy, and θz directions) is always detected with a resolution of about 0.25 nm, for example. Here, in practice, as shown in FIGS. 2 and 3, the movable mirror 27Y having a reflecting surface orthogonal to the Y-axis direction that is the scanning direction and the X-axis direction that is the non-scanning direction are provided on the wafer table 18. The wafer interferometer 31 is provided with one axis in the scanning direction and two axes in the non-scanning direction, but in FIG. , Shown as a wafer interferometer 31. The position information (or speed information) of the wafer table 18 is sent to the main controller 20. Main controller 20 drives wafer stage drive system 50 (see FIG. 6) based on the position information (or velocity information) to control the position (and velocity) of wafer stage WST in the XY plane. .

  As shown in FIG. 3, the wafer stage drive system 50 includes a stator 60 accommodated in the upper part of the stage base 21 and a movable element 52 provided at the bottom of the wafer stage main body 51 as shown in FIG. 3. A planar motor is used. Hereinafter, the wafer stage drive system 50 is also referred to as a planar motor 50 for convenience. Hereinafter, the configuration and the like of the planar motor 50 will be described.

  As shown in part in a sectional view in FIG. 3, the stage base 21 includes a hollow main body portion 35 having a rectangular top view with an open top surface, and a ceramic plate 36 that closes the opening of the main body portion 35 from above. It has. A guide surface 21 a of the wafer stage body 51 is formed on the surface (upper surface) of the ceramic plate 36 facing the wafer stage body 51.

  In FIG. 4A, the stage base 21 from which the ceramic plate 36 has been removed is schematically shown together with the mover 52. As can be seen from FIGS. 4A and 3, the internal space 41 of the stage base 21 formed by the main body 35 and the ceramic plate 36 has a Y coil unit 60Y and a Y coil unit 60Y on the Y coil unit 60Y. A stator 60 composed of stacked X coil units 60X is accommodated. 4B schematically shows the stage base 21 together with the movable element 52 in a state where the X coil unit 60X is removed from FIG. 4A.

For example, as shown in FIG. 4A, the mover 52 has a rectangular shape that is long in the X-axis direction in a plan view, its −X side end and + Y side half area, and + X side end. In addition, magnet units 55X ₁ and 55X ₂ are provided in the region on the −Y side half. Magnet units 55Y ₁ and 55Y ₂ are provided in the + X side end and + Y side half region and the −X side end and −Y side half region of the mover 52, respectively.

The magnet units 55X ₁ and 55X ₂ are composed of a plurality of cubic magnets having a longitudinal direction in the Y-axis direction and arranged at a predetermined pitch in the X-axis direction. The plurality of magnets are determined so that the polarities of the magnetic pole surfaces are alternately reversed. Similarly, the magnet units 55Y ₁ and 55Y ₂ are composed of a plurality of cube-shaped magnets having the X axis direction as the longitudinal direction and arranged at a predetermined pitch in the Y axis direction. The plurality of magnets are determined so that the polarities of the magnetic pole surfaces are alternately reversed. In each of the magnet units 55X ₁ , 55X ₂ and the magnet units 55Y ₁ , 55Y ₂ , the adjacent magnets may be in contact with each other or may be through a predetermined gap.

  The stator 60 includes a lower Y coil unit 60Y accommodated in the internal space 41 of the stage base 21 and an upper X coil unit 60X. As can be understood from FIGS. 3 and 4A, the X coil unit 60X has a plurality of rows of armature coils 38X arranged in the X axis direction along the guide surface 21a in the upper stage of the internal space 41. It is constituted by. As each armature coil 38X, as shown in FIG. 4A, a rectangular coil whose long side is three times as long as the short side is used.

  The Y coil unit 60Y includes a plurality of rows of electric machines arranged in the Y axis direction along the XY plane at the lower stage of the internal space 41 of the stage base 21, as can be understood from FIGS. 3 and 4B. It is comprised by the child coil 38Y. As each armature coil 38Y, as shown in FIG. 4B, a rectangular coil whose long side is three times the length of the short side is used.

  In the armature coils 38X in each row constituting the X coil unit 60X, the three armature coils 38X adjacent in the X-axis direction are arranged in a predetermined order for a U-phase coil, a V-phase coil, and a W-phase coil. It is a coil. Similarly, in each armature coil 38Y of each row constituting the Y coil unit 60Y, three armature coils 38Y adjacent in the Y-axis direction are arranged in a predetermined order, a U-phase coil, a V-phase coil, This is a W-phase coil. That is, the planar motor 50 is a three-phase AC motor.

An electromagnetic force (Lorentz force) in the X-axis direction (non-scanning direction) acts on the X coil unit 60X (armature coil 38X) due to electromagnetic interaction between the magnet units 55X ₁ and 55X _2, and this reaction force Acts as a driving force for the magnet units 55X ₁ and 55X ₂ (wafer stage WST). The Y coil unit 60Y (armature coil 38Y) is subjected to electromagnetic force (Lorentz force) in the Y-axis direction (scanning direction) due to electromagnetic interaction between the magnet units 55Y ₁ and 55Y _2. The force acts as a driving force for the magnet units 55Y ₁ and 55Y ₂ (wafer stage WST). In this way, wafer stage WST is driven in the XY two-dimensional direction on stage base 21 by planar motor 50. The magnitude and direction of the current supplied to the armature coils 38X and 38Y are controlled by the main controller 20 (see FIG. 6).

As described above, the planar motor 50, X coil unit 60X (armature coils 38X) is in the upper part of the inner space 41 of the stage base 21 closer to the magnet unit _55X 1, 55X _2, Y coil unit 60Y (armature coils 38Y Are stacked in the lower stage of the internal space 41 of the stage base 21. In such an arrangement, in the exposure apparatus 100 according to the present embodiment, in the step-and-scan type exposure operation described later, the movement direction of the wafer stage WST at the time of stepping between shot areas is used in the scanning direction (Y A U-shaped path having a larger driving distance in the non-scanning direction (X-axis direction) (equal to the dimension in the X-axis direction of the shot area) than the driving distance in the axial direction is defined. This is because a larger driving force (acceleration, thrust) is required for driving in the X-axis direction than for driving in the axial direction (scanning direction).

Furthermore, in the planar motor 50 according to the present embodiment, the X coil unit 60X and the Y coil unit 60Y have different thicknesses. As can be seen from FIG. 3, the thickness of the Y coil unit 60Y disposed farther from the mover 52 (magnet units 55Y ₁ , 55Y ₂ ) is set larger than the thickness of the X coil unit 60X. Yes.

  In FIG. 5A, the thickness of the X coil unit 60X (X coil thickness) is 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, and 10 mm. ) On the horizontal axis, the amount of heat generated with respect to the sum of the thicknesses of the X coil unit 60X and the Y coil unit 60Y (coil thickness) is shown. FIG. 5A shows that the X coil thickness of 5 mm and the Y coil thickness of 14 to 16 mm generate the smallest amount of heat. Therefore, the coil thickness is set to a thickness that minimizes the amount of heat generation. Thus, the heat generation amount of the stator 60 (the limit heat generation amount that reaches the limit temperature of the coil) so that the temperatures of the X coil unit 60X and the Y coil unit 60Y do not exceed their heat resistance temperature (limit temperature). Is designed.

  FIG. 5B shows, as an example, the relationship between the thickness of the Y coil unit 60Y (Y coil thickness) and its thermal conductivity. The relationship between the thickness of the X coil unit 60X (X coil thickness) and its thermal conductivity, and the relationship between the sum of the thicknesses of the X coil unit 60X and Y coil unit 60Y (coil thickness) and its thermal conductivity, This is the same as FIG. This will be described. The armature coils 38X and 38Y constituting the X coil unit 60X and the Y coil unit 60Y are formed by laminating predetermined wire materials, for example, flat wires. Each wire is covered with an insulator. Here, the thermal conductivity of the insulator is low. Therefore, as the thickness of the X coil unit 60X and the Y coil unit 60Y increases, that is, when the number of coil wires stacked increases, the thickness of the covering portion increases, so that the thermal conductivity of the armature coil slowly attenuates. . This means a decrease (increase) in heat dissipation with respect to the large thickness (small thickness) of the X coil unit 60X and the Y coil unit 60Y. Therefore, the coil thickness that minimizes the heat generation amount (limit heat generation amount) is set to a smaller thickness, for example, an X coil thickness of 4 mm and a Y coil thickness of 14 mm or less in consideration of thermal conductivity, that is, heat dissipation. You can also.

  On the opposite side (lower surface side) of the ceramic plate 36 from the guide surface 21a, as shown in FIG. 3, a large number of protrusions 36a having a circular cross section are formed at predetermined intervals. When the ceramic plate 36 is assembled to the main body 35, the protrusion 36a is provided at a position corresponding to the space between the four adjacent armature coils 38Y. A cooling liquid is supplied to the internal space 41 of the stage base 21, and the X coil unit 60X and the Y coil unit 60Y are cooled by this liquid.

  Returning to FIG. 1, an off-axis alignment detection system AS is provided on the −Y side of the projection optical system PL. For example, the alignment detection system AS irradiates a target mark with a broadband detection light beam that does not sensitize the resist on the wafer W, and forms an image of the target mark formed on the light receiving surface by reflected light from the target mark (not shown). An image processing type FIA (Field Image Alignment) type alignment sensor that captures an image of each index using an imaging device (CCD) or the like and outputs the imaged signals is used. The imaging result of the alignment detection system AS is sent to the main controller 20.

  Although not shown in FIG. 1, a pair of reticle alignment marks on the reticle R and a pair of first reference marks on a reference mark plate (not shown) on the wafer table 18 corresponding to the reticle R are disposed above the reticle R. A pair of reticle alignment detection systems 13 (see FIG. 6) of a TTR (Through The Reticle) method using an exposure wavelength for simultaneously observing an image via the projection optical system PL are arranged. Detection signals of the pair of reticle alignment detection systems 13 are supplied to the main controller 20.

  In addition, the exposure apparatus 100 is provided with a multipoint focal position detection system including an irradiation system and a light receiving system so as to sandwich the alignment detection system AS.

  FIG. 6 shows the main configuration of the control system of the exposure apparatus 100. The control system is mainly configured of a main controller 20 including a microcomputer (or workstation) that performs overall control of the entire apparatus.

  In the exposure apparatus 100 according to the present embodiment configured as described above, first, reticle loading and wafer loading are performed by a reticle loader and a wafer loader (both not shown) under the control of the main controller 20, respectively. Further, using the pair of reticle alignment detection system 13, the reference mark plate (not shown), and the alignment detection system AS, preparatory work such as reticle alignment and baseline measurement of the alignment detection system AS is performed according to a predetermined procedure.

  After that, the main controller 20 performs alignment measurement (wafer alignment) such as EGA (Enhanced Global Alignment) using the alignment detection system AS.

  After the alignment measurement is completed, a step-and-scan exposure operation is performed as follows. In the exposure operation, first, the wafer stage WST (wafer table) is set so that the XY position of the wafer W becomes a scanning start position (acceleration start position) for exposure of the first shot area (first shot) on the wafer W. 18) is moved. At the same time, the reticle stage RST is moved so that the XY position of the reticle R becomes the scanning start position. The main controller 20 then passes the reticle stage drive system 11 and the planar motor 50 based on the position information of the reticle R measured by the reticle interferometer 16 and the position information of the wafer W measured by the wafer interferometer 31. Scanning exposure is performed by moving the reticle R and the wafer W synchronously. The movement of the wafer W is performed by controlling at least one of a current value and a current direction supplied to the armature coils 38X and 38Y by the main controller 20. During scanning exposure, the main controller 20 causes the wafer table 18 to be minutely moved in each of the Z-axis, θx, and θy directions via the support mechanisms 32a to 32c based on the measurement result of a multi-point focal position detection system (not shown). When driven, focus / leveling control is performed so that the irradiation area (exposure area) portion of the illumination light IL of the wafer W is matched with the depth of focus of the projection optical system PL.

  When the transfer of the reticle pattern to one shot area is completed in this way, the wafer table 18 is stepped by one shot area along the U-shaped movement path described above, and scanning exposure is performed on the next shot area. . In this way, stepping and scanning exposure are sequentially repeated, and the pattern of the reticle R is superimposed and transferred onto a predetermined number of shot areas on the wafer W.

  As described above, the planar motor 50 included in the exposure apparatus 100 according to the present embodiment includes the X coil unit 60X and the Y coil unit 60Y having different thicknesses. As described above, the thicknesses of the X coil unit 60X and the Y coil unit 60Y are determined so as to minimize the amount of heat generated from the X coil unit 60X and the Y coil unit 60Y. Occurrence of burnout or the like of the Y coil unit 60Y can be almost certainly avoided.

  According to exposure apparatus 100 according to the present embodiment, by providing planar motor 50, temperature fluctuations in the atmosphere around wafer stage WST on stage base 21 can be suppressed. Positioning accuracy can be improved, and the X coil unit 60X for driving in the X axis direction that requires a larger driving force (acceleration, thrust) than driving in the Y axis direction (scanning direction) is provided by the mover 52. Since the X coil unit 60X (and the Y coil unit 60Y) are prevented from generating heat more than necessary, the wafer stage WST can be driven efficiently because it is disposed at a close position. Thereby, the pattern of the reticle R can be accurately formed in a plurality of shot areas (partition areas) on the wafer W with high throughput.

  In the above-described embodiment, the planar motor 50 is described as including a single layer of the X coil unit 60X and the Y coil unit 60Y. However, the present invention is not limited to this, and at least one of the X coil unit 60X and the Y coil unit 60Y (specific The coil unit) may be configured by stacking a plurality of armature coils 38X or 38Y. In this case, the armature coils of the respective layers constituting the specific coil unit may have the same thickness, or may have different thicknesses by the same method as in the above embodiment. For example, even if two layers of Y coil units are stacked and the thickness of one Y coil unit having a large separation distance from the mover is determined to be larger than the other Y coil unit. good.

  In the above embodiment, it is considered that the driving force (acceleration, thrust) in the X-axis direction of wafer stage WST required during stepping between shot areas is larger than the driving force (acceleration, thrust) in Y-axis direction. The X coil unit 60X is disposed above the Y coil unit 60Y, that is, at a position close to the mover 52. Therefore, on the contrary, when the required acceleration (thrust) is larger in the Y-axis direction than in the X-axis direction, the Y coil unit may be disposed on the X coil unit. In this case, the thickness of the X coil unit located below may be larger than the thickness of the Y coil unit. That is, it is desirable to set at least one of the stacking order and thickness of the X coil unit and the Y coil unit in accordance with the acceleration specifications in the X axis direction and the Y axis direction of the wafer stage.

  In the above embodiment, the case where the exposure apparatus is a dry type exposure apparatus that exposes the wafer W without using liquid (water) is described. However, the present invention is not limited to this, and for example, International Publication No. 99/49504. No. 1, European Patent Application Publication No. 1,420,298, International Publication No. 2004/055803, US Pat. No. 6,952,253, etc. The planar motor according to the above embodiment is also applied to an exposure apparatus that forms an immersion space including an optical path of illumination light between the projection optical system and exposes the wafer with illumination light through the projection optical system and the liquid in the immersion space. Can do. In addition, the planar motor according to the above embodiment can be applied to an immersion exposure apparatus disclosed in, for example, International Publication No. 2007/097379 (corresponding to US Patent Application Publication No. 2008/088843). .

  In the above-described embodiment, the case where the exposure apparatus is a scanning exposure apparatus such as a step-and-scan method has been described. However, the present invention is not limited to this, and the stationary exposure apparatus such as a stepper has a flat surface according to the above-described embodiment. A motor may be applied. Further, the planar motor according to the above-described embodiment can be applied to a step-and-stitch reduction projection exposure apparatus, a proximity exposure apparatus, or a mirror projection aligner that combines a shot area and a shot area. it can. Further, as disclosed in, for example, US Pat. No. 6,590,634, US Pat. No. 5,969,441, US Pat. No. 6,208,407, etc. As disclosed in a multi-stage type exposure apparatus having a stage, for example, WO 2005/074014, a measurement member (for example, a reference mark and / or a sensor) is included separately from the wafer stage. The planar motor according to the above-described embodiment can also be applied to an exposure apparatus that includes a measurement stage.

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

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

  In the above embodiment, it is needless to say that the illumination light IL of the exposure apparatus is not limited to light having a wavelength of 100 nm or more, and light having a wavelength of less than 100 nm may be used. For example, the above embodiment is also 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), an exposure apparatus using a charged particle beam such as an electron beam or an ion beam, and the like. Such a planar motor can be applied.

  Further, as disclosed in, for example, US Pat. No. 6,611,316, two reticle patterns are synthesized on a wafer via a projection optical system, and 1 on the wafer by one scan exposure. The planar motor according to the above embodiment can also be applied to an exposure apparatus that performs double exposure of two shot areas almost simultaneously.

  In the above embodiment, the object on which the pattern is to be formed (the object to be exposed to which the energy beam is irradiated) is not limited to the wafer, but may be another object such as a glass plate, a ceramic substrate, a film member, or a mask blank. good.

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

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

10 ... illumination system 21 ... stage base, 38X, 38Y ... armature coil, 50 ... stage drive system (planar motor), 52 ... _{mover, 55X 1, 55X 2, 55Y} 1, 55Y 2 ... magnet unit, 60 ... Stator, 60X ... X coil unit, 60Y ... Y coil unit, 100 ... exposure apparatus, PL ... projection optical system, W ... wafer, WST ... wafer stage.

Claims (11)

A mover having first and second magnet units each including a magnet provided on a movable body movable in first and second directions orthogonal to each other on the base;
A plurality of sets of first coils arranged in the base so as to face the mover, and at least one layer of a first coil unit that applies a driving force in the first direction to the mover; A second set of at least one layer that includes a plurality of sets of second coils arranged in the base so as to face the mover across one coil unit, and applies a driving force in the second direction to the mover. A stator having a coil unit;
A flat motor in which the at least one first coil unit and the at least one second coil unit have different thicknesses.   The planar motor according to claim 1, wherein the driving force in the first direction is larger than the driving force in the second direction.   The planar motor according to claim 2, wherein a thickness of the at least one second coil unit is larger than a thickness of the at least one first coil unit.   The planar motor according to any one of claims 1 to 3, wherein the first and second coil units have a thickness determined so that a total heat generation amount is minimized.   The flat motor according to claim 4, wherein the first and second coil units have thicknesses determined so that a total heat radiation amount is increased.   The flat motor according to any one of claims 1 to 5, wherein the thicknesses of the first and second coil units are set according to the specifications of acceleration in the first direction and the second direction.   The planar motor according to any one of claims 1 to 6, wherein at least one of the first and second coil units is laminated in a plurality of layers in the base.   The second coil unit is laminated in two layers, and the thickness of one of the two coil units having a large separation distance from the mover is larger than the thickness of the other second coil unit. Item 8. The flat motor according to Item 7. An exposure apparatus that exposes an object with an energy beam,
The planar motor according to any one of claims 1 to 8, wherein the movable body that holds the object is driven in the first and second directions.
An exposure apparatus comprising: a pattern generation device that generates a pattern on the object by irradiating the object with the energy beam. An exposure apparatus that exposes an object with an energy beam to form a pattern in a plurality of partitioned areas on the object,
The planar motor according to any one of claims 1 to 8, wherein the movable body that holds the object is driven in the first and second directions.
An exposure apparatus comprising: a pattern generation device configured to irradiate the energy beam onto the object driven in the second direction to generate the pattern in each of a plurality of partitioned regions on the object. Exposing an object using the exposure apparatus according to claim 9 or 10 to form a pattern on the object;
Developing the object with the pattern formed thereon;
A device manufacturing method including:

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