JP2007214336A - Retaining device, manufacturing method therefor retaining method, stage device, and exposure device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To propose a retaining device, a retaining method or the like capable of disposing on a retaining surface while suppressing warpage or the like even if the warpage or the like has been generated in a plate member. <P>SOLUTION: The retaining device WH is provided with a retaining member 1 having a retaining surface 2 for retaining the plate member W while being opposed to the first surface Wb of the plate member W; a movable member 77 for supporting the plate member W to move the plate member W into a direction intersecting with the retaining surface 2 of the plate member W, and to dispose the same on the retaining surface 2; and a gas supplying unit 10 for supplying gas A between the plate type member W supported by the movable member 77 and the retaining surface 2. In this case, the plate member W supported by the movable member 77 is flattened by employing the gas A supplied from the gas supplying unit 10 before the plate member W is retained on the retaining surface 2. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a holding apparatus, a holding method, a stage apparatus, an exposure apparatus, and a device manufacturing method.

  In a lithography process for manufacturing a semiconductor element or the like, a step-and-repeat type reduction projection exposure apparatus (so-called stepper) and a step-and-scan type scanning projection exposure apparatus (so-called scanning stepper) are used. Projection exposure apparatuses have become mainstream. In such a projection exposure apparatus, a substrate stage movable in a two-dimensional plane is provided, and a photosensitive substrate is held by vacuum suction or electrostatic suction by a substrate holder fixed on the substrate stage. ing.

In the exposure apparatus, the demand for finer patterns formed on the photosensitive substrate is increasing with the increase in the capacity of the semiconductor memory and the increase in the speed and integration of the CPU processor, and high exposure accuracy is required. ing.
For this reason, as a substrate holder, when a foreign object is caught between the photosensitive substrate and the photosensitive substrate surface, irregularities are formed on the surface of the photosensitive substrate, resulting in defocusing during exposure, and hence deterioration in exposure accuracy. As disclosed in No. 1 and the like, a pin chuck type substrate holder that supports a photosensitive substrate by a large number of pin-shaped support portions has been proposed.
Japanese Patent Laid-Open No. 1-129438

The photosensitive substrate placed on the substrate holder is made of, for example, silicon, and is a thin disk having a diameter of 8 inches (200 mm) or 12 inches (300 mm) and a thickness of about 0.5 mm to 1.0 mm. . For this reason, the photosensitive substrate itself is often warped or wavy.
When the photosensitive substrate warped or waved in this way is sucked and held by the substrate holder, the photosensitive substrate is forcibly stretched and held on the substrate holder. However, since the photosensitive substrate is not uniformly stretched, there is a problem that the photosensitive substrate is locally deformed. Further, since there is almost no reproducibility in how the photosensitive substrate is stretched, there is a problem that the alignment mark formed on the photosensitive substrate is displaced every time the photosensitive substrate is sucked and held on the substrate holder. For this reason, it is difficult to perform pattern superposition with high accuracy.

  The present invention has been made in view of the above-described circumstances, and a holding device that can be placed on a holding surface while suppressing warpage or the like even when warpage or the like occurs in a plate-like member, It is an object of the present invention to propose a holding method, a stage apparatus, an exposure apparatus, and a device manufacturing method.

  In the holding apparatus, holding method, stage apparatus, exposure apparatus, and device manufacturing method according to the present invention, the following means corresponding to the respective drawings shown in the embodiments are employed in order to solve the above problems. However, the reference numerals with parentheses attached to each element are merely examples of the element and do not limit each element.

  1st invention supports the said plate-shaped member and the holding member (1) which has the holding surface (2) which opposes the 1st surface (Wb) of a plate-shaped member (W), and hold | maintains this plate-shaped member. Then, the movable member (77) that moves the plate-like member in a direction intersecting the holding surface and places the plate-like member on the holding surface, and the plate-like member supported by the movable member and the holding surface A holding device (WH) having a gas supply unit (10) for supplying a gas (A) between the plate and the plate-like member supplied from the gas supply unit before being held on the holding surface The plate-like member supported by the movable member is flattened using a gas to be used.

  The holding device (WH) includes a holding member (1) having a holding surface (2) that holds the plate-like member facing the first surface (Wb) of the plate-like member (W), and the plate-like member. A movable member (77) that supports the member and moves the plate-like member in a direction intersecting the holding surface and places the plate-like member on the holding surface; and the first member in the plate-like member supported by the movable member. The first gas supply part (10) for supplying the gas (A) between the one surface and the holding surface is opposed to the second surface (Wa) opposite to the first surface of the plate member. A second gas supply unit (26) having an opposing surface (20b) and supplying gas (A) between the opposing surface and the plate-like member; the first gas supply unit; and the second gas supply. And an adjustment unit (CONT) for adjusting the supply state of the gas in at least one of the units.

  The holding device (WH2) includes a holding member (31) having a holding surface (32) for holding the plate-like member (W), and supports the plate-like member so that the plate-like member intersects the holding surface. A movable member (77) that is moved in the direction of movement and placed on the holding surface, and a gas supply unit that supplies gas (A) between the plate-like member supported by the movable member and the holding surface (46), the gas suction part (40) for sucking the gas between the plate-like member supported by the movable member and the holding surface, the gas supply part and the gas suction part were operated simultaneously. The adjustment part (CONT) which adjusts the gas supply state in the said gas supply part and the gas suction state in the said gas suction part in the state was included.

  A second invention is a holding method for holding a plate-like member (W) on a holding surface (2), and the plate-like member is moved by a movable member (77) movable in a direction intersecting the holding surface. Gas (A) is supplied between the step of supporting, the step of moving the plate-like member toward the holding surface by the movable member, and the plate-like member supported by the movable member and the holding surface Thus, the step of flattening the plate-like member supported by the movable member and the step of placing the flattened plate-like member on the holding surface are included.

13
Moreover, it is a holding method which hold | maintains a plate-shaped member (W) on a holding surface (2), Comprising: The movable member (77) which can move to the direction which cross | intersects the said holding surface WHEREIN: A member (20b) having a step of supporting Wb) in a state of facing the holding surface, and a facing surface (20b) facing the second surface (Wa) opposite to the first surface of the plate-like member. ) To supply gas (A) between the opposing surface and the plate member, and between the first surface and the holding surface of the plate member supported by the movable member The step of flattening the plate-like member supported by the possible member by supplying gas and the step of placing the flattened plate-like member on the holding surface are included. .

14
A method of holding the plate member (W) on the holding surface (32), the step of supporting the plate member by a movable member (77) movable in a direction intersecting the holding surface; Supported by the movable member by supplying the gas (A) and sucking the gas in the space between the first surface (Wb) of the plate-shaped member supported by the movable member and the holding surface. The step of flattening the plate-like member and the step of placing the flattened plate-like member on the holding surface are included.

  In the third invention, the stage device (WST) that holds and moves the plate-like member (W) includes the holding device (WH, WH2) according to the first invention.

  A fourth invention is an exposure apparatus (EX) for forming a predetermined image on a substrate (W) held on a substrate stage (WST), wherein the stage apparatus (3) WST) was used.

  According to a fifth aspect of the present invention, in the device manufacturing method including the lithography step, the exposure apparatus (EX) according to the fourth aspect of the invention is used in the lithography step.

According to the present invention, the following effects can be obtained.
Prior to placing the substrate on the holding surface, it is possible to correct the warp and the like generated on the substrate, so that the substrate can be sucked and held on the holding surface without leaving deformation or the like. As a result, the substrate can be accurately positioned by the stage device, so that a fine pattern can be exposed with high accuracy. Therefore, it is possible to efficiently obtain a high-quality and high-performance device.

Hereinafter, embodiments of a holding apparatus, a holding method, a stage apparatus, an exposure apparatus, and a device manufacturing method according to the present invention will be described with reference to the drawings.
[First embodiment]
FIG. 1 is a view showing a schematic configuration of an exposure apparatus EX of the present embodiment.
The exposure apparatus EX transfers the pattern PA formed on the reticle R to each shot area on the wafer W via the projection optical system PL while moving the reticle R and the wafer W synchronously in the one-dimensional direction. A scanning type exposure apparatus, that is, a so-called scanning stepper.
The exposure apparatus EX includes an illumination optical system IL that illuminates the reticle R with exposure light EL, a reticle stage RST that can move while holding the reticle R, and projection optics that projects the exposure light EL emitted from the reticle R onto the wafer W. A system PL, a wafer stage WST that can move while supporting the wafer W via a wafer holder WH, a control device CONT that controls the exposure apparatus EX in an integrated manner, and the like are provided.
In the following description, the direction that coincides with the optical axis AX of the projection optical system PL is the Z-axis direction, and the synchronous movement direction (scanning direction) between the reticle R and the wafer W in the plane perpendicular to the Z-axis direction is the X-axis. The direction perpendicular to the direction, the Z-axis direction, and the Y-axis direction (non-scanning direction) is defined as the Y-axis direction. In addition, the rotation (inclination) directions around the X, Y, and Z axes are the θX, θY, and θZ directions, respectively.

  The illumination optical system IL illuminates the reticle R supported by the reticle stage RST with the exposure light EL. The illumination light source emits the exposure light EL, and the illuminance of the exposure light EL emitted from the exposure light source. A uniform optical integrator, a condenser lens that collects the exposure light EL from the optical integrator, a relay lens system, a variable field stop that sets the illumination area on the reticle R by the exposure light EL in a slit shape, etc. (all not shown) Is provided. The predetermined illumination area on the reticle R is illuminated with the exposure light EL having a uniform illuminance distribution by the illumination optical system IL.

As the exposure light EL emitted from the illumination optical system IL, for example, far ultraviolet light (g-line, h-line, i-line) and KrF excimer laser light (wavelength 248 nm) emitted from a mercury lamp, DUV light), vacuum ultraviolet light (VUV light) such as ArF excimer laser light (wavelength 193 nm) and F ₂ laser light (wavelength 157 nm), or the like is used.

The reticle stage RST is movable while holding the reticle R, and, for example, the reticle R is fixed by vacuum suction (or electrostatic suction). Reticle stage RST can be moved two-dimensionally in a plane perpendicular to optical axis AX of projection optical system PL, that is, in the XY plane, and can be slightly rotated in the θZ direction.
The reticle stage RST is driven by a reticle stage drive unit RSTD such as a linear motor. Reticle stage driving unit RSTD is controlled by control unit CONT.

  A movable mirror 51 is provided on the reticle stage RST. A laser interferometer 52 is provided at a position facing the movable mirror 51. Thus, the position of the reticle R on the reticle stage RST in the two-dimensional direction (XY direction) and the rotation angle in the θZ direction (including rotation angles in the θX and θY directions in some cases) are measured by the laser interferometer 52 in real time. Is done. And the measurement result of the laser interferometer 52 is output to the control apparatus CONT. The control device CONT controls the position of the reticle R supported by the reticle stage RST by driving the reticle stage drive unit RSTD based on the measurement result of the laser interferometer 52.

The projection optical system PL projects and exposes the pattern of the reticle R onto the wafer W at a predetermined projection magnification β. The projection optical system PL is composed of a plurality of optical elements including optical elements provided at the front end portion on the wafer W side, and these optical elements are supported by a lens barrel PK. The projection optical system PL is a reduction system having a projection magnification β of, for example, 1/4, 1/5, or 1/8.
Note that the projection optical system PL may be either an equal magnification system or an enlargement system. Further, the optical element at the tip of the projection optical system PL is detachably (replaceable) with respect to the lens barrel PK.

Wafer stage WST moves while supporting wafer W, and holds wafer W via wafer holder WH so that it is micro-driven in three degrees of freedom in the Z-axis direction, θX direction, and θY direction. 61, an XY table 62 that continuously moves in the Y-axis direction and steps in the X-axis direction while supporting the Z table 61, a wafer surface plate 63 that supports the XY table 62 to be movable in the XY plane, and the like. .
Wafer stage WST is driven by a wafer stage drive unit WSTD such as a linear motor. Wafer stage drive unit WSTD is controlled by control unit CONT. Then, by driving the Z table 61, the position (focus position) in the Z-axis direction of the wafer W held by the wafer holder WH on the Z table 61 is controlled. Further, by driving the XY table 62, the position of the wafer W in the XY direction (position in a direction substantially parallel to the image plane of the projection optical system PL) is controlled.
The detailed configuration of the wafer holder WH will be described later.

  A movable mirror 53 is provided on wafer stage WST (Z table 61). A laser interferometer 54 is provided at a position facing the moving mirror 53. Thus, the position and rotation angle of wafer W on wafer stage WST in the two-dimensional direction are measured in real time by laser interferometer 54, and the measurement result is output to control unit CONT. Then, the control device CONT drives the wafer stage WST via the wafer stage drive unit WSTD based on the measurement result of the laser interferometer 54, so that the X axis and Y axis of the wafer W supported on the wafer stage WST. Positioning in the direction and θZ direction.

Further, the exposure apparatus EX includes a focus detection system 56 that detects the position (focus position) of the surface of the wafer W with respect to the image plane of the projection optical system PL. The focus detection system 56 includes a light projecting unit 56A that projects detection light on the surface of the wafer W from an oblique direction, and a light receiving unit 56B that receives detection light (reflected light) reflected from the surface of the wafer W.
The light reception result of the light receiving unit 56B is output to the control device CONT. Then, the control device CONT drives the wafer stage WST (Z table 61) via the wafer stage drive unit WSTD based on the detection result of the focus detection system 56, thereby determining the position of the surface of the wafer W of the projection optical system PL. Keep within the depth of focus. In other words, the Z table 61 controls the focus position and the tilt angle of the wafer W to adjust the surface of the wafer W to the image plane of the projection optical system PL by the auto focus method and the auto leveling method.

Next, a detailed configuration of the wafer holder WH will be described.
2 is a side sectional view of the wafer holder WH, and FIG. 3 is a plan view of the holder plate 1 as viewed from above.
The wafer holder WH includes a holder plate 1 having a predetermined shape, an air supply / exhaust device 10 and the like. The holder plate 1 has a shape corresponding to the wafer W, and is formed, for example, in a substantially circular shape in plan view.
On the upper surface 2 of the holder plate 1, a convex seal portion 7 formed in an annular shape (endless shape) having a predetermined width in the vicinity of the outer peripheral portion, and a plurality of protrusions provided at a predetermined interval in an inner region of the seal portion 7 A pin portion 8 is provided. The lower surface of the wafer W is supported at a plurality of locations by the seal portion 7 and the plurality of pin portions 8.
The lower surface 3 of the holder plate 1 is formed flat and is an area that is mounted on the Z table 61 by a suction mechanism (not shown). Since the Z table 61 is also formed flat, even when the wafer holder WH is mounted on the Z table 61, the upper surface 2 is hardly deformed.
The holder plate 1 is made of ceramic, for example, silicon carbide ceramics (SiC: silicon carbide). Since silicon carbide ceramics have high thermal conductivity and a low coefficient of linear expansion, the temperature can be transmitted without thermal deformation. Moreover, since workability is favorable, the upper surface 2 and the lower surface 3 can be formed with high flatness.

The upper end surfaces of the plurality of pin portions 8 and the upper end surfaces of the seal portions 7 provided on the upper surface 2 of the holder plate 1 are formed so as to be flat and on the same plane. That is, a holding surface (upper surface 2) that holds the wafer W is formed by the plurality of pin portions 8 and the seal portion 7. In this way, the wafer W can be held flat on the upper ends of the pin portion 8 and the seal portion 7.
The seal portion 7 is formed so as to have an outer diameter slightly smaller than the outer diameter of the wafer W placed thereon.

As shown in FIG. 3, air supply / exhaust holes 5 are formed at a plurality of predetermined positions on the upper surface 2 of the holder plate 1. For example, the air supply / exhaust holes 5 are formed at 12 locations in the radial direction from the center of the upper surface 2. The air supply / exhaust hole 5 is a hole that penetrates the holder plate 1 in the vertical direction, and is connected to the air supply / exhaust device 10 via a flow path 12 formed in the Z table 61 on which the holder plate 1 is placed. For example, the exhaust holes 5 are formed at 12 locations in the radial direction from the center of the upper surface 2.
With this configuration, when the air supply / exhaust device 10 performs an exhaust operation (suction operation), the air A between the wafer W and the upper surface 2 of the holder plate 1 passes through the flow path 12 from the air supply / exhaust hole 5. It comes to be sucked. As a result, the space surrounded by the wafer W and the seal portion 7 becomes negative pressure, and the wafer W is attracted to the upper surface 2 of the holder plate 1.
On the other hand, when the air supply / exhaust device 10 performs an air supply operation (blowout operation), air A is supplied from the air supply / exhaust hole 5 between the wafer W and the upper surface 2 of the holder plate 1.

The holder plate 1 is formed with lift pin holes 9a in which lift pins 77 that hold the wafer W and can be moved up and down are arranged. The lift pins 77 and the lift pin holes 9a corresponding to the lift pins 77 are provided at positions corresponding to the apexes of the equilateral triangle in the vicinity of the center portion of the upper surface 2. A seal portion 9 that is formed in an annular shape (endless shape) and has substantially the same height as the pin portion 8 is also provided around the lift pin hole 9a.
The three lift pins 77 can move up and down by the same amount in the vertical direction (Z-axis direction) simultaneously. During loading and unloading of the wafer W with respect to the wafer holder WH, the lift pins 77 are moved up and down by the drive mechanism 70, so that the wafer W can be supported from below or moved up and down with the wafer W supported from below. It can be done.
Each lift pin 77 is formed with a suction path 77a that opens to the top surface of the tip, and each suction path 77a is connected to a vacuum suction source (not shown). Thus, when the wafer W is placed on the three lift pins 77, the wafer W is sucked (exhausted) through the suction path 77a, so that the wafer W is sucked and held so as not to be displaced.

Returning to FIG. 2, between the XY table 62 and the Z table 61, an actuator 80 for adjusting the position of the Z table 61 (wafer W) with respect to the imaging plane of the projection optical system PL, and the wafer W are moved up and down in the Z direction. A driving mechanism 70 is provided.
The actuator 80 includes a voice coil motor, and includes a stator 80A provided on the XY table 62 and a mover 80B provided on the Z table 61 and movable in the Z direction. The actuator 80 is provided at three locations, and the Z table 61 is finely driven in three degrees of freedom in the Z-axis direction, θX direction, and θY direction by driving the actuators 80 respectively.

The drive mechanism 70 includes a rectangular block-shaped base portion 71, a guide device 72 that guides the base portion 71 so as to be movable in the Z direction, and a plurality of gears 73a linearly provided in one side surface of the base portion 71. Aligned rack 73, pinion 74 that meshes with gear 73a of rack 73 and rotates about an axis orthogonal to the plane of the paper, and rotary motor that is provided in the vicinity of base portion 71 and rotates pinion 74 under the control of control device CONT 75, and a linear scale 76 that detects the position of the base portion 71 in the Z-axis direction and outputs it to the control device CONT.
Then, three lift pins 77 are disposed on the upper surface of the rectangular block-shaped base portion 71 along the Z-axis.

In addition, a plate-like member 20 having substantially the same shape as the holder plate 1 is disposed above the wafer holder WH (see FIGS. 1 and 4).
The lower surface 20b of the plate-like member 20 is formed flat, and air supply holes 22 are formed at a plurality of predetermined positions on the lower surface 20b. For example, twelve air supply holes 22 are formed at positions facing each of the air supply / exhaust holes 5 formed in the upper surface 2 of the holder plate 1. Each air supply hole 22 is a hole that penetrates the plate-like member 20 in the vertical direction, and is connected to an air supply device 26 via a flow path 24.
With such a configuration, when the air supply device 26 performs an air supply operation (blowout operation), air A is supplied from the air supply holes 22 between the wafer W and the lower surface 20b of the plate-like member 20. It has become.
Plate member 20 is provided at a wafer load / unload position within the movable range of wafer stage WST. The plate-like member 20 can be moved in the Z direction by a vertical drive unit 81 such as a motor.

Next, an operation when placing the wafer W on the wafer holder WH (holder plate 1) will be described.
FIG. 4 is a diagram illustrating an operation when the wafer W is placed on the wafer holder WH (holder plate 1).
First, wafer stage WST (Z table 61 and XY table 62) moves to a wafer load / unload position in order to load wafer W. Then, the driving mechanism 70 is driven to raise the three lift pins 77 and project from the upper surface 2 of the holder plate 1.
Next, the lift pins 77 are further lifted, and the wafer W transported above the wafer holder WH (holder plate 1) by the wafer transport arm 82 movable in the XY plane direction is placed on the lift pins 77, and then lifted to the lift pins 77. The wafer W is sucked and held through the formed suction path 77a.

The wafer W placed on the lift pins 77 is a thin disk made of, for example, silicon and having a diameter of 300 mm and a thickness of 1.0 mm or less. For this reason, the wafer W itself is often warped or wavy. When the wafer W thus warped or waved is placed on the wafer holder WH (holder plate 1) and sucked as it is, the wafer W is forcibly stretched on the holder plate 1 (on the holder plate 1). Slip occurs between some of the pin portions 8 and the wafer W and is held.
However, the way the wafer W is stretched is not uniform, and there is almost no reproducibility. For this reason, every time the wafer W is sucked and held on the holder plate 1, the wafer W is locally deformed. Thereby, there exists a possibility that exposure accuracy may deteriorate.

Therefore, the warp or the like generated on the wafer W is corrected while the wafer W is placed on the lift pins 77. Specifically, in a state where the wafer W is sucked and held on the lift pins 77, air A is uniformly blown onto the upper surface Wa and the lower surface Wb of the wafer W, and the pressure (stiffness of the formed air layer) is applied to the wafer W. Correct any warping that occurs.
First, the drive mechanism 70 is driven to lower the three lift pins 77 to bring the wafer W close to the holder plate 1 so that the distance between the upper surface 2 of the holder plate 1 and the lower surface Wb of the wafer W is 1 mm or less, preferably Is about several μm. Instead of lowering the three lift pins 77, the actuator 80 is driven to raise the Z table 61 (holder plate 1), so that the distance between the upper surface 2 of the holder plate 1 and the lower surface Wb of the wafer W is as described above. You may make it become the grade which carried out.
Further, the plate member 20 is brought close to the wafer W at the same time when the wafer W and the holder plate 1 are brought close to each other. The distance between the lower surface 20b of the plate member 20 and the upper surface Wa of the wafer W is set to 1 mm or less, preferably about several μm. That is, the distance between the upper surface 2 of the holder plate 1 and the lower surface Wb of the wafer W and the distance between the lower surface 20b of the plate member 20 and the upper surface Wa of the wafer W are made the same.

Next, the air supply / exhaust device 10 and the air supply device 26 are operated to blow air A toward the wafer W from the air supply / exhaust holes 5 of the holder plate 1 and the air supply holes 22 of the plate-like member 20. At this time, the state of air A (mainly pressure and flow rate) blown toward the wafer W from the air supply / exhaust hole 5 and the air supply hole 22 is substantially uniform. As a result, as shown in FIG. 4, the air layer AB1 formed between the upper surface 2 of the holder plate 1 and the lower surface Wb of the wafer W, and the space between the lower surface 20b of the plate-like member 20 and the upper surface Wa of the wafer W. The air layer AB2 is formed so as to have the same rigidity.
Then, by applying a uniform force to the upper surface Wa and the lower surface Wb of the wafer W, the warp and the like generated in the wafer W having a lower rigidity than the air layers AB1 and AB2 are corrected, and the wafer W is flattened.

Next, the wafer W is moved toward the holder plate 1 in a flattened state. The movement of the wafer W may be performed by driving the driving mechanism 70 to lower the lift pins 77 that attract and hold the wafer W, or driving the actuator 80 to raise the Z table 61 (holder plate 1). You may go on. In any case, as the wafer W approaches the holder plate 1, the state (flow rate or pressure) of the air A blown from the air supply / exhaust hole 5 of the holder plate 1 is changed (decrease in the flow rate or pressure). By changing the state (pressure and flow rate) of the air A blown from the air supply / exhaust hole 5 according to the distance between the upper surface 2 of the holder plate 1 and the lower surface Wb of the wafer W, the upper surface 2 of the holder plate 1 and the wafer W The rigidity of the air layer AB1 formed between the lower surface Wb is maintained constant.
When moving toward the wafer W holder plate 1, the distance between the plate member 20 and the wafer W and the state of the air A blown toward the wafer W from the air supply holes 22 of the plate member 20 are always maintained constant. To do. Thereby, the rigidity of the air layer AB2 formed between the lower surface 20b of the plate-like member 20 and the upper surface Wa of the wafer W is also maintained constant.
In this way, even when the wafer W is moved toward the holder plate 1, the state in which the wafer W is flattened is maintained.

Next, when the wafer W moves and comes into close contact with the upper surface 2 of the holder plate 1, the blowing of the air A from the air supply / exhaust hole 5 of the holder plate 1 is stopped and the air supply / exhaust device 10 is switched to the suction (exhaust) operation. At the same time, the air supply device 26 is stopped, and the blowing of the air A from the air supply holes 22 of the plate-like member 20 is stopped.
Thereby, the wafer W is sucked and held on the holder plate 1 in a state where the warpage or the like occurring on the wafer W is corrected.
Next, the suction of the wafer W by the lift pins 77 is stopped and the lift pins 77 are lowered. Further, the loading operation of the wafer W is completed by lifting and retracting the plate-like member 20 by a vertical drive unit (not shown). Then, the exposure process for the wafer W is started.

As described above, according to the present embodiment, air having the same rigidity on the upper surface Wa side and the lower surface Wb side of the wafer W prior to placing the wafer W on the upper surface 2 of the wafer holder WH (holder plate 1). By forming the layers AB1 and AB2, a uniform force is applied to the upper surface Wa and the lower surface Wb of the wafer W. Thereby, the warp etc. which generate | occur | produced in the low-rigidity wafer W are corrected, and the wafer W is planarized.
Since the flattened wafer W is sucked and held on the wafer holder WH, a fine pattern can be exposed on the wafer W with high accuracy.

[Second Embodiment]
FIG. 5 is a side sectional view of the wafer holder WH2, and FIG. 6 is a plan view of the holder plate 31 as viewed from above. In the following description, parts different from those of the first embodiment will be mainly described, and the same components are denoted by the same reference numerals and the description thereof will be omitted.
The wafer holder WH2 includes a holder plate 31, an exhaust device 40, an air supply device 46, and the like. The holder plate 31 is formed with a ring-shaped convex seal portion 37 and a plurality of projecting pin portions 38 provided at a predetermined interval, and the plurality of pin portions 38 and the seal portion 37 form a wafer. A holding surface (upper surface 32) for holding W is formed. Further, the holder plate 31 is formed with a lift pin hole 39 a and a convex seal portion 39.

As shown in FIG. 6, exhaust holes 35 and air supply holes 36 are formed at a plurality of predetermined positions on the upper surface 32 of the holder plate 31. For example, the exhaust holes 35 and the air supply holes 36 are respectively formed at 12 locations in the radial direction from the center of the upper surface 32. The exhaust hole 35 is a hole penetrating the holder plate 31 in the vertical direction, and is connected to the exhaust device 40 via a flow path 42 formed in the Z table 61 on which the holder plate 31 is placed. Similarly, the air supply hole 36 is also connected to the air supply device 46 via a flow path 48 formed in the Z table 61.
With this configuration, when the exhaust device 40 performs an exhaust operation (suction operation), the air A between the wafer W and the upper surface 32 of the holder plate 31 is sucked from the exhaust hole 35 through the flow path 42. It has become so. On the other hand, when the air supply device 46 performs an air supply operation (blowout operation), air A is supplied from the air supply hole 36 between the wafer W and the upper surface 32 of the holder plate 31.
The exhaust holes 35 and the air supply holes 36 do not have to be the same number. The air formed between the wafer W and the holder plate 31 when the air A is supplied from the air supply hole 36 and the air A is sucked from the exhaust hole 35 between the wafer W and the upper surface 32 of the holder plate 31. The number, size, and arrangement of the exhaust holes 35 and the air supply holes 36 are determined so that the layer AB3 is in a substantially uniform state (a state in which no pressure distribution is generated).

Next, an operation when placing the wafer W on the wafer holder WH will be described.
FIG. 7 is a diagram illustrating an operation when the wafer W is placed on the wafer holder WH.
First, wafer stage WST (Z table 61 and XY table 62) moves to a wafer load / unload position in order to load wafer W. Then, the drive mechanism 70 is driven to raise the three lift pins 77 so as to protrude from the upper surface 32 of the holder plate 31.
Next, the wafer W is placed on the lift pins 77 by a wafer transfer arm (not shown), and the wafers W are sucked and held via suction paths 77 a formed in the lift pins 77.
Next, the drive mechanism 70 is driven to lower the three lift pins 77 (or the actuator 80 is driven to raise the Z table 61 (holder plate 1)), and the wafer W is brought close to the holder plate 31. The distance between the upper surface 32 of the holder plate 31 and the lower surface Wb of the wafer W is set to 1 mm or less, preferably about several μm.

Next, the exhaust device 40 is operated, and air A is blown toward the wafer W from the exhaust hole 35 of the holder plate 31. At the same time, the air supply device 46 is operated to suck air A from the space between the air supply hole 36 of the holder plate 31 and the wafer W.
At this time, an air layer formed between the holder plate 31 and the wafer W by adjusting the state (mainly pressure and flow rate) of the air A blown from the exhaust hole 35 and the air A sucked from the air supply hole 36. The rigidity of AB3 can be set arbitrarily. Thus, as shown in FIG. 7, by adjusting the rigidity of the air layer AB3, it is possible to correct the warp generated in the wafer W and to flatten the wafer W.

Next, the wafer W is moved toward the holder plate 31 in a flattened state. The wafer W may be moved by driving the drive mechanism 70 to lower the lift pins 77 that attract and hold the wafer W, or driving the actuator 80 to raise the Z table 61 (holder plate 31). You may go on. In any case, as the wafer W approaches the holder plate 31, the state (flow rate or pressure) of the air A blown from the exhaust hole 35 and the air A sucked from the air supply hole 36 is changed (flow rate or pressure). Lower). As a result, the rigidity of the air layer AB3 formed between the upper surface 32 of the holder plate 31 and the lower surface Wb of the wafer W is maintained constant, so that the warp generated on the wafer W is corrected (flattened). The wafer W can be moved. When moving the wafer W, it is preferable to reduce the servo rigidity of the drive mechanism 70 (rotary motor 75) or the actuator 80. This is because the distance between the wafer W and the holder plate 31 can be adjusted flexibly according to the rigidity of the air layer AB3.
Next, when the wafer W moves and comes into close contact with the upper surface 32 of the holder plate 31, the air supply device 46 is stopped, and the blowing of the air A from the air supply holes 36 of the holder plate 31 is stopped. On the other hand, by continuing the suction operation of the exhaust device 40 through the exhaust hole 35, the wafer W is attracted and held on the holder plate 31 in a state in which the warp or the like generated on the wafer W is corrected.
Next, the wafer W loading operation is completed by stopping the suction of the wafer W by the lift pins 77 and lowering the lift pins 77. Then, the exposure process for the wafer W is started.

As described above, according to the present embodiment, before the wafer W is placed on the upper surface 32 of the wafer holder WH (holder plate 31), the air layer AB3 having arbitrary rigidity is formed on the lower surface Wb side of the wafer W. As a result, the warp or the like generated in the wafer W is corrected, and the wafer W is flattened.
Since the flattened wafer W is sucked and held on the wafer holder WH, a fine pattern can be exposed on the wafer W with high accuracy.

Although the embodiment of the present invention has been described above, the operation procedure shown in the above-described embodiment, or the shapes and combinations of the constituent members are examples, and the process is within the scope not departing from the gist of the present invention. Various changes can be made based on conditions and design requirements.
For example, the present invention includes the following modifications.

  In the above-described embodiment, the case where the wafer holders WH and WH2 attract and hold the wafer W has been described. However, the present invention is not limited to this, and the wafer W may be electrostatically attracted. Even in this case, until the wafer W is placed on the holder plates 1 and 31 of the wafer holders WH and WH2, only the wafer W is adsorbed according to the above-described procedure.

  Further, in the above-described embodiment, the example in which the substrate holding device according to the present invention is applied to the wafer holder WH that holds the wafer W has been described. For example, in a reflective reticle, the back side is held by a reticle holder (mask holder). Therefore, the present invention can also be applied to such a reticle holder.

  Further, a notch portion into which the transfer arm 82 enters the holder plate 1 may be provided, and the wafer W may be placed on the holder plate 1 by moving the transfer arm 82 up and down. In this case, the air A may be blown only on the lower surface Wb in the state where the wafer W is sucked and held on the transfer arm 82, as in the above embodiment.

The exposure apparatus EX of the above embodiment can be applied to a scanning type exposure apparatus that exposes the pattern of the reticle R by synchronously moving the reticle R and the wafer W, and the reticle R and the wafer W are stationary. In this state, the pattern of the reticle R is exposed, and it can be applied to a step-and-repeat type exposure apparatus that sequentially moves the wafer W stepwise.
The exposure apparatus EX may be an immersion type exposure apparatus that exposes the wafer W by disposing the liquid between the projection optical system PL and the wafer W and solving the liquid.

  The use of the exposure apparatus EX is not limited to an exposure apparatus for manufacturing a semiconductor or an exposure apparatus for liquid crystal that exposes a liquid crystal display element pattern on a square glass plate, but exposure for manufacturing a thin film magnetic head. Widely applicable to devices.

The exposure apparatus EX of the present embodiment is manufactured by assembling various subsystems including the constituent elements recited in the claims of the present application so as to maintain predetermined mechanical accuracy, electrical accuracy, and optical accuracy. Is done. In order to ensure these various accuracies, before and after assembly, various optical systems are adjusted to achieve optical accuracy, various mechanical systems are adjusted to achieve mechanical accuracy, and various electrical systems are Adjustments are made to achieve electrical accuracy.
The assembly process from the various subsystems to the exposure apparatus includes mechanical connection, electrical circuit wiring connection, pneumatic circuit piping connection and the like between the various subsystems. Needless to say, there is an assembly process for each subsystem before the assembly process from the various subsystems to the exposure apparatus. When the assembly process of the various subsystems to the exposure apparatus is completed, comprehensive adjustment is performed to ensure various accuracies as the entire exposure apparatus.
The exposure apparatus is preferably manufactured in a clean room where the temperature, cleanliness, etc. are controlled.

  Then, as shown in FIG. 8, the semiconductor device has a step 201 for designing the function / performance of the device, a step 202 for producing a mask (reticle) based on the design step, and a substrate (wafer, Glass plate) step 203, substrate processing step 204 for exposing the pattern of the reticle R onto the wafer W by the exposure apparatus of the above-described embodiment, device assembly step (including dicing process, bonding process, and packaging process) 205, inspection It is manufactured through step 206 and the like.

It is a figure which shows schematic structure of the exposure apparatus EX which concerns on embodiment of this invention. It is a sectional side view of the wafer holder WH which concerns on embodiment of this invention. It is the top view which looked at the holder board 1 from upper direction. It is a figure which shows the operation | movement at the time of mounting the wafer W on the wafer holder WH. It is a sectional side view of wafer holder WH2 concerning the embodiment of the present invention. It is the top view which looked at the holder board 31 from upper direction. It is a figure which shows the operation | movement at the time of mounting the wafer W on the wafer holder WH. It is a flowchart figure which shows an example of the manufacturing process of the microdevice which concerns on embodiment of this invention.

Explanation of symbols

1 ... Holder plate (holding member)
2. Top surface (holding surface)
5 ... Air supply / exhaust hole 10 ... Air supply / exhaust device (gas supply unit)
20 ... Plate-shaped member (member)
20b ... lower surface (opposite surface)
22 ... Air supply hole 26 ... Air supply device (second gas supply unit)
31 ... Holder plate (holding member)
32 ... Upper surface (holding surface)
35 ... Exhaust hole 36 ... Air supply hole 40 ... Exhaust device (gas suction part)
46 ... Air supply device (gas supply unit)
77 ... Lift pin (movable member)
EX ... Exposure device CONT ... Control device (adjustment unit)
WST ... Wafer stage (stage device, substrate stage)
WH, WH2 ... Wafer holder (substrate holding device)
W: Wafer (plate member, substrate)
A ... Air (gas)
AB1, AB2, AB3 ... Air layer

Claims (17)

A holding member having a holding surface for holding the plate-like member facing the first surface of the plate-like member;
A movable member that supports the plate-like member and moves the plate-like member in a direction intersecting the holding surface to be placed on the holding surface;
A holding device including a gas supply unit configured to supply gas between the plate-like member supported by the movable member and the holding surface;
Before the plate-like member is held on the holding surface, the holding member flattening the plate-like member supported by the movable member using the gas supplied from the gas supply unit . A holding member having a holding surface for holding the plate-like member facing the first surface of the plate-like member;
A movable member that supports the plate-like member and moves the plate-like member in a direction intersecting the holding surface to be placed on the holding surface;
A first gas supply unit for supplying gas between the first surface and the holding surface in the plate-like member supported by the movable member;
A second gas supply unit that has a facing surface facing the second surface opposite to the first surface of the plate-shaped member, and supplies gas between the facing surface and the plate-shaped member;
An adjusting unit for adjusting the supply state of the gas in at least one of the first gas supply unit and the second gas supply unit;
A holding device comprising:   The said adjustment part adjusts the supply state of the said gas in said 1st gas supply part according to the distance of the said plate-shaped member and the said holding surface, The holding | maintenance of Claim 1 or Claim 2 characterized by the above-mentioned. apparatus.   The holding device according to claim 3, wherein the adjustment unit adjusts a supply state of the gas when the plate-like member supported by the movable member moves toward the holding surface.   The said 2nd gas supply part can move the said opposing surface so that the distance between the said opposing surface and the said plate-shaped member may be maintained constant, The Claim 2 to Claim 4 characterized by the above-mentioned. The holding device according to any one of claims.   The holding device according to any one of claims 1 to 5, further comprising a suction portion for sucking and holding the plate-like member on the holding surface.   Supply and suction of the gas are shared by at least a part of the flow path through which the gas is supplied in the first gas supply unit and the flow path through which the gas is sucked when the adsorption unit adsorbs the plate member. The holding device according to claim 6, wherein the two can be switched to each other. A holding member having a holding surface for holding a plate-like member;
A movable member that supports the plate-like member and moves the plate-like member in a direction intersecting the holding surface to be placed on the holding surface;
A gas supply unit for supplying gas between the plate-like member supported by the movable member and the holding surface;
A gas suction part for sucking a gas between the plate-like member supported by the movable member and the holding surface;
An adjustment unit that adjusts the gas supply state in the gas supply unit and the gas suction state in the gas suction unit while the gas supply unit and the gas suction unit are operated simultaneously,
A holding device comprising:   The holding device according to claim 8, wherein the adjustment unit adjusts a supply state of the gas in the gas supply unit according to a distance between the plate-like member and the holding surface.   The holding according to claim 8 or 9, wherein the adjustment unit adjusts the suction state of the gas in the gas suction unit according to a distance between the plate-like member and the holding surface. apparatus.   The holding device according to any one of claims 1 to 10, wherein the holding surface electrostatically attracts the plate-like member. A holding method for holding a plate-like member on a holding surface,
Supporting the plate-like member by a movable member movable in a direction intersecting the holding surface;
Moving the plate-shaped member toward the holding surface by the movable member;
Flattening the plate-like member supported by the movable member by supplying gas between the plate-like member supported by the movable member and the holding surface;
Placing the flattened plate-like member on the holding surface;
The holding method characterized by including. A holding method for holding a plate-like member on a holding surface,
Supporting the first surface of the plate-like member in a state of facing the holding surface by a movable member movable in a direction intersecting the holding surface;
A member having a facing surface opposite to the second surface opposite to the first surface of the plate-like member is arranged to supply gas between the facing surface and the plate-like member, and the movable member Flattening the plate member supported by the possible member by supplying gas between the first surface and the holding surface of the plate member supported by
Placing the flattened plate-like member on the holding surface;
The holding method characterized by including. A method of holding a plate-like member on a holding surface,
Supporting the plate-like member by a movable member movable in a direction intersecting the holding surface;
The plate-like member supported by the movable member is flattened by supplying gas and sucking gas in a space between the first surface of the plate-like member supported by the movable member and the holding surface. The process of
Placing the flattened plate-like member on the holding surface;
The holding method characterized by including. A stage device that is movable while holding a plate-shaped member,
A stage device comprising the holding device according to any one of claims 1 to 11. An exposure apparatus that forms a predetermined image on a substrate held on a substrate stage,
An exposure apparatus using the stage apparatus according to claim 15 as the substrate stage.   A device manufacturing method including a lithography process, wherein the exposure apparatus according to claim 16 is used in the lithography process.

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