JP6732429B2 - Substrate holding apparatus, lithographic apparatus, and article manufacturing method - Google Patents

Description

The present invention relates to a substrate holding device, a lithographic apparatus, and a method for manufacturing an article.

A substrate having irregularities or warpage may be supplied to an exposure apparatus used in the manufacturing process of semiconductor devices and the like. When the substrate is held by vacuum suction, a warp of the peripheral edge of the substrate may cause a leak and weaken the suction force. Further, when the pattern is transferred to the substrate in a state where the suction force is weak and the unevenness or warpage of the substrate is large, the transfer pattern may be distorted and the device manufacturing yield may be reduced.

Patent Document 1 relates to a holding device in which an elastic seal member is provided on the outer periphery of a substrate holding surface. By deforming the seal member along the peripheral shape of the substrate, the leakage of the space between the substrate and the substrate holding surface is reduced and the suction force is enhanced. The substrate holding surface of the holding device has a plate-shaped member including intake holes that have the same size and the same shape and are formed at regular intervals.

JP, 2002-217276, A

When the air is simultaneously sucked by the suction holes formed with the same size, the same shape and a constant interval as in the holding device described in Patent Document 1, the negative pressure distribution on the substrate holding surface is uniform or on the peripheral side. Becomes lower. Considering that the substrate with large distortion such as warp is often carried into the exposure apparatus due to the diversification of device manufacturing process in recent years, it is caused by the weak suction force on the substrate peripheral side. Therefore, it may be difficult to correct the warp of the substrate edge.

Therefore, the present invention can correct the warp of the substrate as compared with the case where the same vacuum source is used to simultaneously inhale using the air holes having the same size, the same shape, and a constant interval. An object is to provide a holding device and a lithographic apparatus.

A substrate holding device of the present invention is a substrate holding device for holding a substrate, wherein a holding member provided with a plurality of suction holes for exhausting a space between the substrate and the holding member having a lower step portion is provided. And an annular seal member that defines the space, and has the same center as the center of the plane figure on the holding surface of the holding member, and the plane figure is set to 2/3 or more and 4/5 or less. When the first area inside the reduced figure and the second area between the first area and the seal member are set, (total area of intake holes provided in the second area/ Area of the second region)> (total area of intake holes provided in a region where the first region and the second region are added/area of a region where the first region and the second region are added) The plurality of intake holes are provided so as to satisfy the above, the plurality of intake holes communicate with a common pipe, and the holding member is provided with an annular convex portion inside the seal member, and at least one of the above The intake hole is provided in a region surrounded by the convex portion, at least one of the intake holes is provided in an area outside the convex portion, and at least one of the intake air is provided in an area outside the convex portion. The hole is provided on a side surface of the step portion so as to face the seal member .

The substrate holding device of the present invention can correct the warp of the substrate as compared with the case where the same vacuum source is used to simultaneously inhale by using the air holes having the same size, the same shape, and a constant interval. it can.

The figure of the exposure apparatus which concerns on 1st-3rd embodiment. The figure of the holding|maintenance apparatus which concerns on 1st Embodiment (sectional view seen from the horizontal direction). FIG. 8 is a diagram of a holding device according to a modified example of the first embodiment (a cross-sectional view seen from the horizontal direction). The figure of the holding|maintenance apparatus which concerns on 1st Embodiment (the figure seen from the upright direction). The figure of the holding device concerning an example. The figure of the holding device concerning a 2nd embodiment. The figure of the holding|maintenance apparatus which concerns on 3rd Embodiment. The figure of the holding device concerning the modification of a 3rd embodiment. Explanatory drawing (1) of other shapes of a lip seal. Explanatory drawing (2) of other shapes of a lip seal.

[First Embodiment]
The configuration of an exposure apparatus (lithography apparatus) 1 according to the first embodiment will be described with reference to FIG. The exposure apparatus 1 irradiates the i-line (wavelength 365 nm) as the illumination light (beam) 6 while scanning the reticle 2 and the substrate 3 by the step-and-repeat method, and the pattern (formed on the reticle 2 For example, a projection type exposure apparatus that transfers a circuit pattern or the like) onto the substrate 3. In FIG. 1, the axis parallel to the optical axis of the projection optical system 4 (the vertical direction in this embodiment) is the Z axis. In the plane perpendicular to the Z axis, the direction in which the reticle 2 scans during exposure is the X axis, and the non-scanning direction orthogonal to the X axis is the Y axis.

The illumination light 6 formed by the illumination optical system 5 is applied to the substrate 3 via the reticle 2 and the projection optical system 4. The substrate 3 is, for example, a single crystal silicon substrate and has a resist coated on its surface. The reticle 2 moves with the stage 7. The interferometer 8 irradiates the mirror 9 with a laser beam and receives the reflected light to detect the position of the stage 7. The stage 7 has a stage top plate (not shown) for the reticle and a moving mechanism (not shown) for moving the stage top plate.

The substrate 3 moves in six axis directions together with the holding device 10 that holds the substrate 3 by vacuum suction and the stage 13. The interferometer 11 uses the mirror 12 to detect the position of the stage 13 in the same manner as the position detection of the stage 7. The stage 13 has a stage top plate (not shown) for the substrate and a moving mechanism (not shown) for moving the stage top plate.

The detection system 14 detects an alignment mark (not shown) formed on the substrate 3 and a reference mark (not shown) formed on the mark base 15 installed on the stage 13. The detection system detects the positions of the alignment mark and the reference mark, and the control unit 18 described later determines the pattern formation position. The detection system 14 is an off-axis alignment detection system that detects alignment marks and reference marks without the projection optical system 4.

The holding device 10 includes a chuck (holding member) 16 that holds the substrate 3 by suction, a pin 17 that supports the substrate 3 when the substrate 3 is loaded and unloaded, and an elevating mechanism that lifts and lowers the chuck 16 along the Z-axis direction. Shown). By the lifting/lowering operation of the chuck 16, the substrate 3 is delivered from the pin 17 to the chuck 16 when the substrate is loaded, and from the chuck 16 to the pin 17 when the substrate is unloaded. The configuration of the holding device 10 will be described in detail later.

The control unit 18 is connected to the stages 7 and 13, the detection system 14, the interferometers 8 and 11, and the holding device 10, and controls these in a centralized manner. For example, at the time of exposure processing, the pattern formation position is determined based on the detection result of the detection system 14, and the movement of the stages 7 and 13 is controlled based on the position information obtained from the interferometers 8 and 11. Further, when the substrate 3 is carried in and out, the lifting mechanism of the holding device 10 and the movement of the stage 13 are controlled. The control unit 18 may be configured in a housing that houses components other than the control unit 18, or may be configured in a housing different from the housing.

The suction operation of the substrate 3 will be described with reference to FIGS. 2A and 2B are cross-sectional views showing the XZ plane passing through the center of the chuck 16 with respect to the chuck 16 and its peripheral members.

FIG. 2A shows a state in which the substrate 3 has been delivered to the chuck 16 after the loading of the substrate 3 is completed. The chuck 16 includes a central portion (first region) and a peripheral portion (second region). The boundary between the central portion and the peripheral portion is shown by a virtual boundary 38. A plurality of suction holes (intake holes) 32 are formed in the central portion and the peripheral portion.

Here, in the present embodiment, the central portion is a circle concentric with the center of the substrate holding surface set as the boundary 38 among the substrate holding surfaces (holding surfaces) that are the surface of the chuck 16 and face the substrate 3. This is the inner area. The peripheral portion is a region outside the boundary 38. The boundary 38 is set so that the area of the central portion is the same as the area of the peripheral portion. In addition, the peripheral edge portion includes a side surface 39b of the step portion 39a of the chuck 16 for providing the lip seal 31 and a region facing the lip seal 31 described later.

All the suction holes 32 communicate with the pipe 33, which is a common pipe for the suction holes 32, via the pipe 33a. The pipe 33 has a role of consolidating the pipes 33 a provided so as to be branched so as to be connected to the respective suction holes 32 into one pipe. The pipe 33 is connected to the vacuum source 33b. A valve 34 is provided between the pipe 33 and the vacuum source 33b. By switching the valve 34, the gas in the space between the chuck 16 and the substrate 3 is discharged from all the suction holes 32 connected through the pipe 33, or the atmosphere to the space between the chuck 16 and the substrate 3 is released. You can select delivery. The pipe 33 is provided at a portion corresponding to the central portion of the chuck 16, that is, a portion inside the boundary 38 when the chuck 16 is cut in the thickness direction at the boundary 38. In particular, as shown in FIG. 2 and the like, it is preferable that the position on the XY plane is provided near the center of the central portion. This is to prevent a difference in strength of the exhaust force between a position where the suction hole 32 and the pipe 33 are close to each other and a position where they are far from each other in the XY plane.

A circular and annular lip seal (seal member) 31 is arranged on the bottom surface 39c of the chuck 16 which is the lower surface of the step portion 39a. The lip seal 31 is an elastic material and is fixed to the chuck 16 using a fixing agent such as an adhesive sheet. When the substrate 3 is placed on the chuck 16, the lip seal 31 comes into contact with the vicinity of the peripheral edge of the substrate 3. In this way, the range of the space 35 between the substrate 3 and the substrate holding surface is defined by the lip seal 31.

The valve 34 is open to the atmosphere space side. Although the vicinity of the peripheral edge of the substrate 3 and the lip seal 31 are in contact with each other, they are not completely in close contact with each other, and there is a portion with a slight gap depending on the warp of the peripheral edge of the substrate 3.

By switching the valve 34 to the vacuum source 33b side from the state of FIG. 2A, the space 35 is exhausted through all the suction holes 32. The switching operation may be performed while the chuck 16 is being raised, that is, before the substrate 3 is completely transferred from the pin 17 to the chuck 16.

As the space 35 becomes a negative pressure, as shown in FIG. 2B, the substrate 3 is pressed by the atmospheric pressure and deforms so as to follow the substrate holding surface of the chuck 16. At this time, the lip seal 31 is deformed along the peripheral shape of the substrate and gradually comes into close contact with the substrate 3.

Since the tip portion of the lip seal 31 is located at a position higher than the substrate holding surface of the chuck 16, even if the edge of the substrate 3 is warped, it is easy for the lip seal 31 to come into contact with the warped portion. Become. As a result, the space 35 can be easily sealed, and the space 35 can be easily exhausted. The space 35 is more hermetically sealed as compared with the case where there is no lip seal, and the suction force of the substrate 3 is increased, whereby the substrate 3 can be straightened.

Therefore, it is preferable that the lip seal 31 is a soft member that is easily deformable and can expand and contract. It is preferable to use a polymer material (elastic polymer material) containing synthetic rubber such as silicone rubber or fluororubber, but other soft resin or metal material may be used.

The exposure device 1 performs the exposure process while the substrate 3 is attracted to the chuck 16 by the holding device 10. After the exposure is finished, the holding device 10 is controlled so that the substrate 3 can be carried out.

FIG. 4 is a view of the chuck 16 viewed from the +Z direction. Adsorption holes 32 and pin holes 36 are formed concentrically on the substrate holding surface.

The pin holes 36 are formed so as to penetrate through the chuck 16 at three locations. When the lifting mechanism moves the chuck 16 in the -Z direction, the pin 17 relatively projects from the inside of the pin hole 36. Since the gap between the pin 17 and the pin hole 36 is always filled with a sealing material (not shown) or the like, no leak occurs when the substrate 3 is sucked.

Four suction holes 32 are formed in the central portion of the chuck 16, and 16 suction holes 32 (eight times two rounds) are formed in the peripheral portion surrounding the central portion. The suction holes 32 all have the same diameter.

Assuming that the total cross-sectional area of all the suction holes 32 in a certain area is the total hole area (total area of the intake holes), the total hole area of the peripheral portion is larger than the total hole area of the central portion. (So that the total area of the intake holes formed in the second area is larger than 50% of the total area of the intake holes formed in the area obtained by adding the first area and the second area) Are formed. Therefore, the total hole area per unit area in the peripheral portion is larger than the total hole area per unit area in the region where the central portion and the peripheral portion are added.

When the vacuum source 33b evacuates the space 35 via the pipe 33 by using the chuck 16 having the suction holes 32 formed in this way, the peripheral portion where the suction holes 32 are formed is more likely to occur in a larger proportion. The adsorption power is larger than that in the central part.

Accordingly, even if the degree of warpage is large and the gap with the lip seal 31 is large after being carried in, the gap can be instantly closed to prevent leakage. Even if the substrates 3 have the same degree of warp, it is easier to correct the warp of the substrate 3 as compared with the case where the suction holes of the same shape are arranged at a constant interval. Therefore, the distortion of the transfer pattern caused by the distortion such as the warp can be prevented.

It is preferable that at least one suction hole 32 is provided on at least one of the side surface 39b and the bottom surface 39c. The state where the suction holes 32 are provided on the side surface 39b is as shown in FIG. 3, for example.

When the substrate holding surface and the substrate 3 are in contact with each other, it is difficult to exhaust air from the suction holes 32 provided in the substrate holding surface. Therefore, the space between the bottom surface 39c and the substrate 3 may not be sufficiently exhausted, and the degree of correction of the warp of the substrate 3 may be insufficient. If the air intake holes 32 are provided on at least one of the side surface 39b and the bottom surface 39c, the space between the bottom surface 39c and the substrate 3 can be exhausted even while the substrate 3 is adsorbed, and the warp can be corrected. it can.

Further, when the intake holes 32 are provided on the side surface 39b, the number of holes to be machined in the vertical direction is small, so that the machining cost required to form the suction holes 32 can be reduced.

With the holding device 10 of the present embodiment, not only the downwardly convex bowl-shaped warped substrate but also the upwardly convex inverted bowl-shaped warped substrate and the asymmetrically warped substrate are attracted. The surface can be straightened.

In the arrangement of the suction holes 32 shown in FIG. 4, the central portion is the area inside the figure having the center of the plane figure on the substrate holding surface and reducing the plane figure to 2/3 or more and 4/5 or less. Alternatively, the peripheral portion may be set as a region between the central portion and the lip seal 31.

In this case, the suction holes 32 are arranged as follows: (total hole area of the peripheral portion/area of the peripheral portion)>(total hole area in a region obtained by adding the central portion and the peripheral portion/(adding the central portion and the peripheral portion) The total hole area per unit area in the peripheral area is larger than the total hole area per unit area in the area where the central area and the peripheral area are added. Thus, the suction force can be increased at the peripheral portion where the suction holes 32 are formed.

">" is an inequality sign indicating that the left term is larger than the right term. “/” means division, and for example, “(total hole area of peripheral portion/area of peripheral portion)” indicates a value obtained by dividing the total hole area of the peripheral portion by the area of the peripheral portion. In the present specification, the plan view of the substrate holding surface means a contour shape when the substrate holding surface is viewed in the vertical direction from the loading side of the substrate 3.

The arrangement of the suction holes 32 is not limited to this embodiment, and various changes can be made. For example, as in the modified example of the present embodiment shown in FIG. 5A, two suction holes 32 may be formed in the central portion and four suction holes 32 may be formed in the peripheral portion uniaxially.

(Example)
Therefore, using the chuck 16 shown in FIG. 5A, the suction effect obtained by forming more suction holes 32 in the peripheral portion than in the central portion of the chuck 16 was confirmed. The suction operation of the bowl-shaped substrate 3 in which the outer peripheral side is arranged 1.7 mm vertically upward from the center is performed. As a comparative example, as shown in FIG. 5B, the same is obtained by using a chuck 50 having six suction holes 48 formed in the central portion and a lip seal 31 arranged along the outer periphery of the chuck 50. The suction operation of the substrate having the degree of warpage was performed.

A flow meter was installed near the valve 34, and the flow rate required to adsorb the substrate 3 was measured.

As a result, the chuck 16 shown in FIG. 5A required a flow rate of 2 L/min (exhaust flow rate), and the chuck 50 shown in FIG. 5B required a flow rate of 20 L/min. The chuck 16 was able to adsorb at a relatively low flow rate even when adsorbing a substrate having a large warp.

From this result, it was found that the configuration of the chuck 16 according to the present embodiment makes it possible to select the vacuum source 33b having a low exhaust performance and a small size. This has the effect of reducing the installation space of the vacuum source 33b and reducing costs.

[Second Embodiment]
The holding device 10 according to the first embodiment is different in the size of the suction holes 37 and the arrangement of the suction holes 32 and 37.

FIG. 6 is a view of the holding device 10 according to the second embodiment as seen from the +Z direction. The boundary 38 shows the boundary between the central portion and the peripheral portion, and the central portion is an area inside the figure obtained by reducing the planar figure on the substrate holding surface to 4/5. The peripheral portion is a region of the substrate holding surface between the central portion and the position of the lip seal 31.

The chuck 16 has two suction holes 32 in the central portion and four suction holes 37 in the peripheral portion. The hole area of one suction hole 37 at the peripheral portion is at least twice as large as the hole area of one suction hole 32 at the central portion. The suction holes 32 are arranged along the Y-axis direction, and the suction holes 37 are arranged along the X-axis direction.

Also in this embodiment, the total hole area per unit area in the peripheral portion is larger than the total hole area per unit area in the region obtained by adding the central portion and the peripheral portion. Even when the central portion is a region in which the plane figure of the substrate holding surface is reduced to 4/5, by arranging the suction holes 32 so that this relationship is established, the suction force on the edge side of the substrate becomes larger. Become.

This makes it easier to correct the warp of the substrate 3 as compared with the case where the suction holes of the same shape are arranged at regular intervals, as in the first embodiment. Therefore, the distortion of the transfer pattern caused by the distortion such as the warp can be prevented. Alternatively, by installing the vacuum source 33b having a low pumping speed, it is possible to reduce the installation space and the cost required for the vacuum source 33b.

Further, by increasing the hole area of one suction hole in the peripheral portion, the number of suction holes 32 formed in the peripheral portion is reduced. Inside the chuck 16, the number of pipes extending from the center to the suction holes 32 can be reduced, and the processing cost can be reduced.

All the suction holes 32 and 37 as shown in FIG. 6 above are arranged the suction holes 32 and 37 so as not aligned in a straight line. This prevents the negative pressure distribution in the space 35 from being uniaxially biased.

In both the first embodiment and the second embodiment, even when there is no suction hole 32 in the central portion (the total hole area in the peripheral portion is 100% of the total area of the central portion and the peripheral portion). The substrate 3 can be adsorbed (if any). However, it is preferable that at least one suction hole 32 is formed in the central portion. This is because if there is no suction hole 32 in the central portion, a plane may be corrected from the end of the substrate 3 and as a result, a region where distortion remains may occur in the center of the substrate 3.

[Third Embodiment]
FIG. 7 is a view of the holding device 10 according to the third embodiment as seen from the +Z direction. The suction holes 32 of the chuck 16 have the same size, the same shape, and are formed at regular intervals. In FIG. 7, the central portion is a region in which the planar figure on the substrate holding surface is reduced to 2/3. However, any area may be used as long as the planar figure on the substrate holding surface is reduced to 2/3 or more and 4/5 or less.

The pipes connected to the suction holes 32 belonging to the respective regions of the central portion and the peripheral portion are provided with valves (not shown) that can be opened and closed in units of regions. The control unit 55 controls opening/closing of the valve corresponding to the central portion and the valve corresponding to the peripheral portion. The control unit 55 forms at a certain timing during the exhaust (exhaust gas flow rate of exhaust performed through the adsorption holes 32 formed in the peripheral portion/area of the peripheral portion)>(region formed by adding the central portion and the peripheral portion). Control of the exhaust flow rate in each of the central and peripheral suction holes 32 so as to satisfy (exhaust flow rate of exhaust gas performed through the suction holes 32/area of a region in which the central portion and the peripheral portion are added) I do.

For example, the control unit 55 draws the substrate 3 only by using the central suction hole 32, then closes the valve of the pipe connected to the central suction hole 32, and then holds the substrate 3 only by the peripheral suction hole 33. Attract. If controlled in this way, the gas is temporarily exhausted only through the suction holes 32 in the peripheral portion. In this way, the suction force at the peripheral portion can be increased. Alternatively, by switching to the vacuum source 33b having a low exhaust performance, it is possible to reduce the installation space and the cost required for the vacuum source 33b.

The adjustment of the exhaust gas flow rate for each region may be performed by adjusting the opening and closing of each valve in the central portion and the peripheral portion. At least at a certain time, the total exhaust flow rate per unit area in the peripheral portion may be larger than the total exhaust flow rate per unit area when exhausting through all the adsorption holes 32. It suffices if the exhaust flow rate can be controlled at.

As another example, as shown in FIG. 8, the chuck 16 may have annular convex portions 43 and 44 in order from the center of the chuck 16 toward the outside. The area 40 surrounded by the convex portion 43 has eight suction holes 32, the area 41 surrounded by the convex portions 43 and 44 has eight suction holes 32, and the area 42 outside the convex portion 33 has Eight suction holes 32 are provided.

The adsorption hole 32 included in the region 40 switches the valve 45 to the vacuum source side to exhaust gas. The adsorption hole 32 included in the region 41 switches the valve 46 to the vacuum source side to exhaust gas. The adsorption holes 32 included in the region 42 can switch the valve 47 to the vacuum source side to exhaust gas. The valves 45, 46, 47 are connected to the control unit 55, and the control unit 55 controls switching of the suction holes 32 used for suctioning the substrate 3 at a predetermined timing.

As described above, in the present embodiment, the height of the tip of the lip seal 31 is set to the height of the substrate holding surface in order to prevent the transport hand (not shown) that transports the substrate 3 to the chuck 16 from colliding with the lip seal 31. It is suitable when it cannot be configured to be too high. That is, it is suitable when the height between the pin 17 and the height of the tip portion of the lip seal 31 becomes narrow when the substrate 3 is carried in and out.

When the lip seal 31 is sufficiently high, it is easy to contact the edge of the substrate 3 where the warp occurs, but when the height of the lip seal 31 is low, depending on the magnitude of the warp of the substrate 3. There is a fear that they cannot contact each other and the space 35 cannot be exhausted sufficiently.

By switching the valves 45, 46, 47 in this order, the substrate 3 can be adsorbed so that the distance between the lip seal 31 and the tip of the substrate 3 is gradually narrowed. After the lip seal 31 and the substrate 3 are in contact with each other, the exhaust flow rate per unit area of the suction holes 32 in the region 42 is controlled to be higher than the exhaust flow rate per unit area of the suction holes 32 in the regions 40 and 41.

As a result, the contact between the lip seal 31 and the transport hand can be prevented, and the warp of the substrate 3 can be corrected.

[Other Embodiments]
In the first to third embodiments, it is preferable to evacuate the space between the valve 34 and the vacuum source 33b during the loading operation of the substrate 3. The air in the space 35 can be exhausted at a moment at the start of the adsorption operation, and even the vacuum source 33b with a small exhaust flow rate can easily adsorb.

The embodiment in which the opening order of the suction holes 32 is controlled as in the third embodiment may be combined with the chuck 16 in which the suction holes 32 are formed in the arrangement according to the other embodiments described above.

The shape of the suction holes 32 is not limited to the circular shape. It may be oval or square. It is preferable that the lip seal 31 is provided such that the tip of the lip seal 31 is located inside a notch area such as a notch or orientation flat formed according to the standard. The lip seal 31 can be prevented from being deteriorated by preventing the exposure light from being directly irradiated to the inside of the lip seal 31.

It is preferable that at least the suction holes 32 are arranged symmetrically with respect to one axis passing through the center of the substrate holding surface. It is possible to prevent a region where the planar correction cannot be locally formed due to an asymmetric distribution of the suction force of the substrate 3.

A plurality of pins (not shown) integrally formed with the chuck 16 may be arranged on the substrate holding surface to reduce the contact area with the substrate 3. By reducing the contact area with the substrate 3, it is possible to prevent dust on the holding surface from adhering to the substrate 3.

Further, when the space sealing ability of the lip seal 31 is insufficient, an annular convex structure ( FIG. 8 ) integral with the chuck 16 is formed on the substrate holding surface inside the lip seal 31 . good. By supplementarily defining the space, planar correction of the central portion of the substrate 3 is facilitated. However, an adsorption hole 32 for adsorbing a space inside the lip seal 31 and outside the annular convex structure to correct the warp of the substrate 3 is formed inside the lip seal 31 and outside the annular convex structure. Need to be

However, even when the above-mentioned pin or annular convex structure is formed, the area of the substrate holding surface, the area of the central portion, and the area of the peripheral portion increase the surface area due to the pin or annular convex structure. I will treat it as having no minutes.

The planar figure on the chuck 16 and the substrate holding surface is not limited to the circular shape. For example, when the substrate holding surface is a quadrangle, the central portion is a similar figure that is concentric with the center of the quadrangle and that is reduced to 2/3 or more and 4/5 or less.

The lip seal 31 does not have to be provided on the horizontal plane as in the first to third embodiments. For example, it may be fixed to the side surface of the chuck 16.

The shape of the lip seal 31 may be such that the tip thereof faces the center of the chuck 16 (FIG. 9). Since the lip seal 31 is likely to be deformed to the central portion with the suction operation of the substrate 3, the substrate 3 is likely to be in close contact with the lip seal 31 and the warp of the peripheral edge of the substrate 3 is easily corrected.

Alternatively, the lip seal 31 may have a bellows-shaped cross section (FIG. 10). The lower the rigidity of the lip seal 31, the better the adhesion to the substrate 3, which is preferable, but it is difficult to reduce the thickness to a predetermined thickness or less due to restrictions in the manufacturing process. Therefore, by using the bellows-shaped lip seal 31, if the rigidity of the contact portion with the substrate 3 is reduced, the substrate 3 can easily adhere to the lip seal 31 and the warp of the peripheral edge of the substrate 3 can be easily corrected. In particular, it is suitable for adsorbing a substrate 3 that is symmetrically warped with respect to one axis passing through the center of the substrate 3 or an asymmetric substrate 3.

In the holding device 10 having the lip seal 31, the substrate 3 may deviate by about 10 to 1000 μm in the predetermined direction before and after the substrate 3 is adsorbed. This is due to individual differences and mounting errors caused by the manufacturing process of the lip seal 31. In this case, the positional deviation is measured in advance using the detection system 8 before the exposure is started, the correction amount is calculated by the arithmetic circuit included in the control unit 18 and the like, and the stages 7 and 13 are scanned with the correction amount taken into consideration. As a result, it is possible to reduce the positional deviation of the substrate 3 caused by the lip seal 31 and prevent the deterioration of the overlay accuracy.

The angle of the lip seal 31 is not limited to the angle shown in FIG. 2A, but may be appropriately changed within the range of 0 to 180 degrees. If the angle is reduced while taking into consideration that it becomes difficult to correct the flat surface of the substrate 3 on the outer peripheral side of the contact point with the substrate 3, the substrate 3 and the lip seal 31 are likely to come into close contact with each other.

Although the lip seal 31 is directly fixed to the chuck 16 in FIG. 4, the lip seal 31 may be fixed by another component to facilitate replacement. The lip seal 31 may be divided into a tip portion including a portion that comes into contact with the substrate 3 and a portion other than the tip portion, and only the worn tip portion may be replaced.

In the embodiment, an example has been shown in which the valve 34 is switched to open to the atmosphere when the substrate 3 after the exposure processing is carried out. However, in addition to the suction hole 32, a small hole that is not connected to the vacuum source 33b and is connected to the atmosphere space may be provided to allow the atmosphere to flow into the space 35.

The light with which the lithographic apparatus of the present invention irradiates the substrate 3 is not limited to i-line (wavelength 365 nm). Light in the far ultraviolet region such as KrF light (wavelength 248 nm) or ArF light (wavelength 193 nm) or g-line (wavelength 436 nm) which is light in the visible light region may be used.

Further, the lithographic apparatus of the present invention is not limited to the exposure apparatus. It may be applied to an apparatus that irradiates a charged particle beam on the substrate 3 to form a latent image pattern on the substrate, or an apparatus that forms a pattern on the substrate by an imprint method.

[Production method]
A method of manufacturing an article (semiconductor integrated circuit device, liquid crystal display device, imaging device, magnetic head, CD-RW, optical device, photomask, etc.) according to an embodiment of the present invention uses a lithographic apparatus to produce a substrate (wafer or wafer). A step of exposing a pattern on a glass plate or the like) and a step of subjecting the exposed substrate to at least one of etching treatment and ion implantation treatment. Further, other known processing steps (development, oxidation, film formation, vapor deposition, planarization, resist peeling, dicing, bonding, packaging, etc.) may be included.

1 Exposure equipment (lithography equipment)
3 substrate 16 chuck (holding member)
31 Lip seal (seal member)
32 Adsorption hole (intake hole)
35 spaces

Claims (12)

A substrate holding device for holding a substrate, comprising:
A holding member provided with a plurality of intake holes for exhausting the space between the substrate and;
An annular seal member that is provided on the lower side of the step portion of the holding member and defines the space,
A first region having the same center as the center of the plane figure on the holding surface of the holding member and being inside the figure obtained by reducing the plane figure to 2/3 or more and 4/5 or less, the first region and the seal. If you set the second area between the member,
(Total area of intake holes provided in the second area/area of the second area)>(Total area of intake holes provided in an area obtained by adding the first area and the second area/the second area (Area of the area obtained by adding one area and the second area)
The plurality of intake holes are provided so as to satisfy
The plurality of intake holes communicate with a common pipe,
An annular convex portion is provided on the holding member inside the seal member, at least one of the intake holes is provided in an area surrounded by the convex portion, and at least one of the intake holes is outside the convex portion. Provided in the area,
The substrate holding device according to claim 1, wherein at least one of the intake holes provided in an area outside the convex portion is provided on a side surface of the step portion so as to face the sealing member. A substrate holding device for holding a substrate, comprising:
A holding member provided with a plurality of intake holes for exhausting the space between the substrate and;
An annular seal member that is provided at the lower side of the step portion of the holding member and that defines the space, and a control unit that controls an exhaust flow rate performed through the intake hole,
The plurality of intake holes communicate with a common pipe,
A first region having the same center as the center of the plane figure on the holding surface of the holding member and being inside the figure obtained by reducing the plane figure to 2/3 or more and 4/5 or less, the first region and the seal. If you set the second area between the member,
The control unit is
(Exhaust flow rate of exhaust gas performed through intake holes provided in the second region/area of the second region)> (through intake holes provided in a region obtained by adding the first region and the second region) (Exhaust flow rate of exhaust gas/area of area where the first area and the second area are added)
The exhaust flow rate is controlled to satisfy
An annular convex portion is provided on the holding member inside the seal member, at least one of the intake holes is provided in a region surrounded by the convex portion, and at least one of the intake holes is provided outside the convex portion. Provided in the area,
The substrate holding device according to claim 1, wherein at least one of the intake holes provided in a region outside the convex portion is provided on a side surface of the step portion so as to face the sealing member. The substrate holding device according to claim 1, wherein at least one of the intake holes is provided in the first region. The substrate holding device according to claim 3, wherein a hole area of one intake hole in the second region is twice or more as large as a hole area of one intake hole in the first region. 5. The substrate holding device according to claim 1, wherein the first region is inside a graphic obtained by reducing the planar graphic to 4/5. The substrate according to claim 1, wherein there are three or more intake holes provided in the holding member, and at least three intake holes are not aligned. Holding device. 7. The substrate holding device according to claim 1, wherein at least one of the intake holes is provided on a side surface of the step portion so as to face the sealing member. The substrate holding device according to claim 1, wherein the sealing member is made of an elastic polymer material. A substrate holding device for holding a substrate, comprising:
A holding member provided with an intake hole for exhausting the space between the substrate and
An annular seal member that is provided on the lower side of the step portion of the holding member and defines the space,
A circle that is concentric with the center of the holding surface of the holding member and has the same area as the first area inside the circle and the area of the second area outside the circle is set. In case,
The total area of the intake holes provided in the second region is greater than 50% of the total area of the intake holes provided in the region obtained by adding the first region and the second region together. An intake hole is provided ,
An annular convex portion is provided on the holding member inside the seal member, at least one of the intake holes is provided in an area surrounded by the convex portion, and at least one of the intake holes is outside the convex portion. Provided in the area,
The substrate holding device according to claim 1, wherein at least one of the intake holes provided in an area outside the convex portion is provided on a side surface of the step portion so as to face the sealing member . The total area of the intake holes provided in the second region is not more than 100% of the total area of the intake holes provided in the region where the first region and the second region are added. The substrate holding device according to claim 9, wherein an intake hole is provided. A holding device according to any one of claims 1 to 10, comprising:
A lithographic apparatus, comprising: irradiating a beam on a substrate held by the holding device to form a pattern on the substrate. A step of irradiating a beam onto a substrate using the lithographic apparatus according to claim 11, and a step of subjecting the substrate to at least one of an etching process and an ion implantation process,
An article manufacturing method comprising: manufacturing an article from the substrate.

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