JP2012134290A - Exposure equipment, stage manufacturing method of the same, and device manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide immersion exposure equipment capable of preventing a liquid from intruding into gaps existing among a plurality of components mounted on a stage of the immersion exposure equipment.SOLUTION: The exposure equipment, to expose a substrate via a liquid, comprises: a stage whose surface is assembled from a plurality of components; and a sealant to seal at least one of the gaps among the components existing on the surface of the stage. For the sealant, a fluororesin tube in an elongated shape, a tape, and a tube made of metal foil provided with a fluororesin layer on the outer surface.

Description

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

  In a photolithography process in a manufacturing process of a micro device such as a semiconductor device or a liquid crystal display device, a pattern formed on the mask is projected and exposed onto a photosensitive substrate by irradiating the mask with exposure light. In order to respond to the recent increase in the density of microdevices, in the photolithography process, it is required to further miniaturize the pattern formed on the substrate. As one of means for realizing such pattern miniaturization, an optical path space of exposure light between the projection optical system and the substrate as disclosed in Patent Document 1 below is liquid (hereinafter referred to as appropriate). An immersion method is described in which the substrate is filled with pure water, for example, and exposed to the substrate through the liquid. In an exposure apparatus used for such an immersion method (hereinafter referred to as an immersion exposure apparatus as appropriate), the liquid exists only in a local area under the projection optical system. The liquid moves in contact with all the shot areas and measurement areas of the measurement stage.

International Publication No. 99/49504 Pamphlet

  A plurality of members (components) are mounted on the stage of the immersion exposure apparatus, and a gap exists between these members. If the immersion liquid enters the stage through the gap, the electrical and mechanical operations are adversely affected. Further, if the liquid remains in the gap without entering the stage, the temperature drop of the stage due to the heat of vaporization at the time of evaporation of the liquid brings about a change in the dimension of the stage, thereby reducing the exposure accuracy.

  In view of such circumstances, an aspect of the present invention is to provide an immersion exposure apparatus capable of preventing liquid from entering a gap existing between a plurality of members mounted on a stage of the immersion exposure apparatus. And

  According to the first aspect, there is provided an exposure apparatus that exposes a substrate through a liquid, the stage having the surface assembled from a plurality of members, and at least one of the members existing on the surface of the stage. An exposure apparatus including a sealing material that seals the gap is provided.

  According to the second aspect, there is provided a method of manufacturing a stage mounted on an exposure apparatus that exposes a substrate through a liquid, wherein the stage is assembled from a plurality of members, and an elongated fluororesin tube is prepared. And inserting the elongated fluororesin tube along the gap into the gap between the members present on the surface of the assembled stage in contact with the liquid, and the fluororesin tube There is provided a method for manufacturing a stage including fixing in the gap and sealing the gap.

  According to the 3rd aspect, the device manufacturing method using the exposure apparatus of a 1st aspect is provided.

  According to the aspect of the present invention, the gap formed between the plurality of members constituting the stage of the immersion exposure apparatus is sealed with the sealing material, so that the immersion liquid enters the stage, and the gap It is possible to prevent the immersion liquid from remaining in the liquid and to protect the immersion exposure apparatus electrically and mechanically, thereby preventing a reduction in exposure accuracy.

It is a figure which shows schematic structure of the exposure apparatus of 1st Embodiment. It is a top view of the wafer stage in FIG. It is a figure which shows the clearance gap which arises between several members (components) mounted in a wafer stage. It is a figure which shows a mode that the sealing material (cross-sectional ellipse) of 1st Embodiment seals the clearance gap between members. It is a flowchart which shows the wafer stage manufacturing method of 1st Embodiment. It is a figure which shows a mode that the sealing material (cross-sectional tear mold) of 1st Embodiment seals the clearance gap between members. It is a figure which shows a mode that the sealing material (section almond type) of 1st Embodiment seals the clearance gap between members. It is a figure which shows a mode that the sealing material of 2nd Embodiment seals the clearance gap between members. It is a figure which shows a mode that the sealing material of 3rd Embodiment seals the clearance gap between members. It is the schematic of the sealing material of 3rd Embodiment. It is a top view of the wafer stage which has a reference member, an illumination intensity nonuniformity sensor, and an aerial image measurement sensor. It is a flowchart which shows an example of the manufacturing process of a semiconductor device.

  Embodiments of an exposure apparatus and an exposure apparatus stage manufacturing method according to aspects of the present invention will be described below with reference to the drawings.

[First Embodiment]
<Exposure device>
The exposure apparatus EX shown in FIG. 1 is a scanning exposure type exposure apparatus composed of a scanning stepper. The exposure apparatus EX includes a projection optical system PL (projection unit PU). In the following, the Z-axis is parallel to the optical axis AX of the projection optical system PL, and a plane orthogonal to this (a plane substantially parallel to the horizontal plane). The Y-axis is taken in the direction in which the reticle and wafer are relatively scanned, the X-axis is taken in the direction perpendicular to the Z-axis and the Y-axis, and the rotation (tilt) directions around the X-axis, Y-axis, and Z-axis are The description will be made with the θx, θy, and θz directions, respectively.

  The exposure apparatus EX includes an illumination system 10, a reticle stage RST that holds a reticle R (mask) illuminated by illumination light (exposure light) IL for exposure from the illumination system 10, and illumination light IL emitted from the reticle R. A projection unit PU including a projection optical system PL that projects onto a wafer W (substrate), a stage device 95 including a wafer stage WST (substrate stage) that holds the wafer W, a control system, and the like are provided.

  The illumination system 10 includes a light source and an illumination optical system, as disclosed in, for example, US Patent Application Publication No. 2003/0025890, and the illumination optical system includes a diffractive optical element and the like. Light distribution forming optical system that forms a light distribution for polar illumination or annular illumination, illuminance uniformizing optical system including optical integrator (such as fly-eye lens or rod integrator), reticle blind, etc. (all not shown) ). The illumination system 10 illuminates the slit-shaped illumination area IAR on the pattern surface of the reticle R defined by the reticle blind with illumination light IL with a substantially uniform illuminance. As the illumination light IL, for example, ArF excimer laser light (wavelength 193 nm) is used. As illumination light, KrF excimer laser light (wavelength 248 nm), harmonics of a YAG laser or a solid-state laser (semiconductor laser, etc.), or a bright line (i-line etc.) of a mercury lamp can be used.

  The reticle R is held on the upper surface of the reticle stage RST by vacuum suction or the like, and a circuit pattern or the like is formed on the pattern surface (lower surface) of the reticle R. The reticle stage RST can be driven minutely in the XY plane by a reticle stage drive system 11 including a linear motor, for example, and can be driven at a scanning speed specified in the scanning direction (Y direction).

  Position information in the moving plane of the reticle stage RST (including the position in the X direction, the Y direction, and the rotation angle in the θz direction) is moved by the reticle interferometer 116 including a laser interferometer (or mirror-finished). For example, it is always detected with a resolution of about 0.5 to 0.1 nm via the stage end face. The measurement value of reticle interferometer 116 is sent to main controller 20. Main controller 20 calculates the position of reticle stage RST in at least the X direction, the Y direction, and the θz direction based on the measurement value, and controls reticle stage drive system 11 based on the calculation result, thereby controlling reticle reticle RST. Control the position and speed of the stage RST.

  In FIG. 1, the projection unit PU disposed below the reticle stage RST includes a lens barrel 40 and a projection optical system PL having a plurality of optical elements held in the lens barrel 40 in a predetermined positional relationship. . The projection optical system PL is, for example, telecentric on both sides and has a predetermined projection magnification β (for example, a reduction magnification of 1/4 times, 1/5 times, etc.). When the illumination area IAR of the reticle R is illuminated by the illumination light IL from the illumination system 10, an image of the circuit pattern of the reticle R in the illumination area IAR through the projection optical system PL by the illumination light IL that has passed through the reticle R. Are formed in an exposure area IA (an area conjugate to the illumination area IAR) on one shot area of the wafer W. The wafer W has a predetermined thickness (for example, about 200 nm) of photoresist (photosensitive agent) on the surface of a disk-shaped base material having a diameter of about 200 mm to 450 mm made of, for example, silicon or SOI (silicon on insulator). Includes coated substrate.

  In addition, since the exposure apparatus EX performs exposure using the immersion method, the lower end of the lens barrel 40 that holds the tip lens 191 that is an optical element on the most image plane side (wafer W side) constituting the projection optical system PL. A nozzle unit 32 constituting a part of the local liquid immersion device 8 is provided so as to surround the periphery of the part. The nozzle unit 32 has a supply port that can supply the exposure liquid Lq (for example, pure water) and a recovery port in which a porous member (mesh) that can recover the immersion liquid Lq is disposed. The supply port of the nozzle unit 32 is connected to a liquid supply device 186 capable of delivering the liquid Lq via a supply flow path and a supply pipe 31A.

  When the wafer W is exposed by the immersion method, the immersion liquid Lq sent from the liquid supply device 186 flows through the supply flow path of the supply pipe 31A and the nozzle unit 32 in FIG. The liquid is supplied to the immersion region 14 on the wafer W including the optical path space of IL. In addition, the immersion liquid Lq recovered from the immersion area 14 via the recovery port of the nozzle unit 32 is recovered by the liquid recovery device 189 via the recovery flow path and the recovery pipe 31B.

  In FIG. 1, wafer stage WST has a clearance of about several μm on upper surface 12 a parallel to the XY plane of base board 12 through a plurality of air pads (not shown), for example, vacuum preload type static air bearings. It is supported without contact. Wafer stage WST can be driven in the X and Y directions by a stage driving system 124 including, for example, a planar motor or two sets of orthogonal linear motors. Further, exposure apparatus EX includes a position measurement system including an encoder system in order to measure position information of wafer stage WST.

  Wafer stage WST includes stage main body 91 driven in the X and Y directions, wafer table WTB mounted on stage main body 91, and wafer table WTB (wafer for stage main body 91) provided in stage main body 91. W) and a Z / leveling mechanism (not shown) that relatively finely drives the position in the Z direction and the tilt angles in the θx direction and the θy direction. A wafer holder (not shown) that holds the wafer W on a suction surface substantially parallel to the XY plane by vacuum suction or the like is provided at the upper center of the wafer table WTB.

  Further, as shown in FIG. 2, on the upper surface of the wafer table WTB, a surface (or a liquid repellent treatment with respect to the immersion liquid Lq) that is substantially flush with the surface of the wafer W placed on the wafer holder (or A flat plate body 28 having a high flatness and having a rectangular outer shape (contour) and a circular opening that is slightly larger than the wafer holder (wafer mounting region) at the center thereof. Is provided.

  As shown in the plan view of wafer table WTB (wafer stage WST) in FIG. 2, plate body 28 surrounds the circular opening and has a surface having a rectangular outer shape (contour) subjected to liquid repellent treatment. (Liquid-repellent plate) 28a, a pair of first and second scale bodies (grating plates) 28b, 28c elongated in the X direction and sandwiching the plate portion 28a in the Y direction, and the plate portion 28a It has a pair of third and fourth scale bodies (grating plates) 28d and 28e elongated in the Y direction so as to be sandwiched in the direction. The scale bodies 28b and 28c have the same configuration, and the scale bodies 28d and 28e have a configuration obtained by rotating the scale bodies 28b and 28c by 90 °.

  X-axis diffraction gratings 39X1 and 39X2 are formed on the surfaces of the first and second scale bodies 28b and 28c, and Y-axis diffraction gratings 39Y1 and 39Y2 are formed on the surfaces of the third and fourth scale bodies 28d and 28e. Is formed. The diffraction gratings 39X1, 39X2, 39Y1, and 39Y2 are reflection type diffraction gratings in which grating lines 37 and 38 having the Y direction and the X direction as the longitudinal direction are formed along the X direction and the Y direction at a predetermined period (pitch), respectively. (For example, a phase type diffraction grating). The diffraction gratings 39X1 to 39Y2 are reflective diffraction gratings formed on the surfaces of the scale bodies 28b to 28e by, for example, holograms (for example, created by baking interference fringes on a photosensitive resin) with a period of 100 nm to 4 μm (for example, a period of 2 μm). It can produce by forming. The diffraction grating formed on each scale body may be produced by mechanically forming a groove or the like. In FIG. 2, for convenience of illustration, the period of the diffraction grating is illustrated much wider than the actual period. Since the scale bodies 28b to 28d have the same configuration, a schematic configuration of the scale body 28d will be described as a representative.

The scale body 28d is a flat plate member having a diffraction grating 39Y1 having a predetermined period PY in the Y direction (measurement direction) on the surface. In addition, in order to protect the surface of the diffraction grating 39Y1, a flat cover glass (not shown) may be disposed through a thin adhesive layer so as to cover the surface. The scale body 28d is made of a material having a low coefficient of thermal expansion, such as glass, glass ceramics (for example, Zerodure (trade name) manufactured by Shot), or ceramics (for example, Al ₂ O ₃ or TiC). The scale body 28d is, for example, held by suction on the surface of the wafer table WTB.

  The exposure apparatus EX of the present embodiment includes a position measurement system including an encoder system using the diffraction grating in order to obtain stage displacement information. Around the nozzle unit 32 at the lower end of the projection optical system PL, a detection head (not shown) including a laser light source, which is a part of the encoder system, is provided. The detection head irradiates a laser beam to the diffraction gratings 39X1, 39X2, 39Y1, and 39Y2 formed with a predetermined period in the Y direction and the X direction, respectively, and photoelectrically converts interference light composed of diffracted light generated from the diffraction grating. The position of the diffraction grating in the Y direction and the X direction, that is, the position of the stage is measured with a resolution of 0.5 to 0.1 nm, for example, with an accuracy of about several nm.

  Furthermore, in this embodiment, a reference mark plate (not shown) on which a reference mark is formed is fixed to a part of the plate portion 28a shown in FIG. A reticle alignment system (not shown) for measuring the positional relationship between the reference mark and the image of the alignment mark of the reticle R corresponding to the reference mark is installed on the bottom surface, and the detection result is supplied to the main controller 20. Furthermore, in this embodiment, a measurement stage (not shown) is mounted on the upper surface 12a of the base board 12 shown in FIG. 1 so as to be movable in the X direction and the Y direction independently of the wafer stage WST. For example, an aerial image measurement device (not shown) that measures the imaging characteristics of the projection optical system PL is disposed on the measurement stage.

  As shown in FIG. 2, the surface of wafer stage WST (WTB) is assembled from a plurality of members (28a to 28e). As described above, since the grating plates 28b to 28e are part of the position measurement system that detects the position of the stage, avoid contact with the water repellent plate 28a so as not to cause distortion due to stress. Installed. Therefore, as shown in FIG. 3, a gap 27 is generated between the water repellent plate 28a and the grating plates 28b to 28e. Further, the interval between the water repellent plate 28a and the grating plates 28b to 28e is not constant, and the width D of the gap 27 varies between about 0.1 to 0.5 mm.

  In order not to create a gap between the water repellent plate 28a and the grating plates 28b to 28e, the water repellent plate 28a and the grating plates 28b to 28e may be formed integrally. Not. First, the grating plates 28b to 28e are precision parts in which a water repellent layer is provided on glass or ceramics, whereas the water repellent board 28a is a part that is provided with a water repellent layer on a metal surface and does not require relatively high accuracy. is there. As described above, it is difficult to form the water repellent plate 28a and the grating plates 28b to 28e having different materials and required accuracy as a single body. Further, since the water repellent plate 28a is a component that is exchanged more frequently than the grating plates 28b to 28e, the water repellent plate 28a and the grating plates 28b to 28e are separate components from the viewpoint of the maintenance cost of the exposure apparatus. It is desirable.

  As shown in FIG. 4, in this embodiment, an elongated fluororesin tube 50 is used as a sealing material for sealing the gap 27 generated between the water repellent plate 28 a and the grating plates 28 b to 28 e. By installing the elongated fluororesin tube 50 in the gap 27 in such a direction that the longitudinal direction thereof is substantially parallel to the surface of the stage, the fluororesin tube 50 is formed with the gap 27 along the gap 27. Seal. In the present embodiment, the “stage surface” is a surface with which the immersion liquid of wafer stage WST (wafer table WTB) comes into contact, and is assembled from a plurality of members such as water repellent plate 28a and grating plates 28b to 28e. The plane is substantially parallel to the XY plane. Thus, by installing the fluororesin tube 50 in the gap 27, the following effects can be obtained.

  Since the fluororesin tube 50 is flexible and hollow, the tube 50 is elastic, fits flexibly to the wall surface forming the gap 27, and can effectively seal the gap 27 having a non-constant width D. . This prevents the immersion liquid from entering the stage. Further, a part of the side wall of the fluororesin tube 50 that seals the gap 27 is exposed on the surface of the wafer table WTB and comes into contact with the immersion liquid. However, since the fluororesin is water repellent, The immersion liquid does not remain on the resin tube 50 and in the recess 51 formed by the fluororesin tube 50 and the wall surface forming the gap 27.

  Furthermore, the fluororesin tube 50 has very little impurity elution into the immersion liquid. Therefore, it is possible to prevent an exposure failure caused by the impurities eluted into the immersion liquid adhering to the wafer W. The fluororesin tube 50 has high durability against ArF excimer laser light, which is deep ultraviolet light used for exposure light, and functions as a sealing material while maintaining water repellency for a long period of time.

  As shown in FIG. 4, the fluororesin tube 50 is installed in the gap 27 in a slightly collapsed state, that is, in a state in which the shape of the cross section perpendicular to the longitudinal direction is deformed into an ellipse. The fluororesin tube 50 in a slightly crushed state tries to restore its cross-sectional shape to a circular shape by elastic force. Therefore, even if the width D of the gap 27 changes, the side surface of the fluororesin tube 50 can always fit to the wall surface forming the gap 27 and seal the gap.

  The fluororesin tube 50 is preferably installed so as to be flush with the surfaces of the water-repellent plate 28a and the grating plates 28b to 28e that are disposed on both sides of the tube and are in contact with each other. When the virtual plane 26 that is flush with the surfaces of the water-repellent plate 28a and the grating plates 28b to 28e in the gap 27 is considered, the wafer 50 of the side surfaces of the fluororesin tube 50 is placed on the virtual plane 26. This means that the portion 52 that protrudes most toward the outside of the stage WST comes into contact. By arranging in this way, the possibility of immersion liquid remaining around the fluororesin tube 50 can be further reduced.

  The fluororesin tube 50 can remain at a specific position in the gap 27 due to its elastic force and frictional force with the wall surface forming the gap 27, but the fluororesin tube 50 is more reliably installed in the gap 27. Therefore, a support member 29 that supports the fluororesin tube 50 (sealing material) from the lower side may be provided at a position corresponding to the gap 27 inside the wafer stage WST. Since the support member 29 supports the fluororesin tube 50 inside the stage, the fluororesin tube 50 is prevented from coming off from the gap 27 for some reason and falling into the stage, and the gap 27 is more reliably sealed. Make things. In FIG. 4, the support member 29 is formed integrally with a member that supports the water repellent plate 28a, but is not limited thereto, and may be formed integrally with a member that supports the grating plates 28b to 28e. .

  Examples of the fluororesin that is a material of the fluororesin tube 50 include polytetrafluoroethylene (PTFE), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA), and tetrafluoroethylene / hexafluoropropylene copolymer (FEP). , Tetrafluoroethylene / ethylene copolymer (ETFE), polychlorotrifluoroethylene (PCTFE), polyvinylidene fluoride (PVDF), and the like. In particular, from the viewpoint of laser durability and water repellency, a PTFE tube and a PFA tube are preferable.

  The diameter of the fluororesin tube 50 (diameter in the cross section perpendicular to the longitudinal direction) is larger than the maximum value of the width D of the gap 27 from the viewpoint of sealing the gap 27, and is easy to handle and work. From the viewpoint, 0.5 mm to 5 mm is preferable. Further, the thickness d50 of the fluororesin tube shown in FIG. 4 is smaller than half the minimum value of the width D of the clearance 27 and 10 μm from the viewpoint of rigidity so that the fluororesin tube 50 can be inserted into the clearance 27. ˜50 μm is preferred. Further, the length of the fluororesin tube 50 in the longitudinal direction can be appropriately selected according to the length of the gap 27 in which it is installed, but from the viewpoint of handleability, workability, and linearity maintenance, 20 cm is preferred.

<Stage manufacturing method>
A method for manufacturing a stage of an exposure apparatus including a method for installing a fluororesin tube will be described with reference to FIG. First, a stage is assembled from a plurality of members (parts) (step S1). In this embodiment, wafer stage WST is assembled from water repellent plate 28a and grating plates 28b to 28e.

  A gap 27 exists between the water repellent plate 28a and the grating plates 28b to 28e, and a fluororesin tube 50 having an appropriate diameter and thickness is prepared in accordance with the width D of the gap 27 (step) S2). For example, various sizes of PTFE tubes for medical use are sold by Zeus, USA, and can be selected and used from time to time.

  The fluororesin tube 50 is deformed so that the cross section perpendicular to the longitudinal direction of the prepared fluororesin tube 50 is a teardrop type (tear drop type, pair shape) having one tip. For example, they are arranged so that the longitudinal direction of the base of the vise (vise) and the longitudinal direction of the fluororesin tube are parallel to each other, and a part of the fluororesin tube is sandwiched between the bases to pressurize the base. In the tube, the portion sandwiched between the caps is crushed to form a tip portion, and the cross section is deformed into a teardrop shape.

  Next, the deformed fluororesin tube 50 is inserted into the gap 27 along the gap 27, that is, so that its longitudinal direction is substantially parallel to the surface of wafer stage WST (step S3). At this time, as shown in FIG. 6, the fluororesin tube is inserted into the gap so that the tip of the deformed fluororesin tube 50 faces the inside of the stage. The fluororesin tube is crushed and deformed, and the width of the tip in the cross section perpendicular to the longitudinal direction is reduced, so that it can be easily inserted into the gap 27. The operation of deforming the fluororesin tube so as to be easily inserted into the gap may be performed immediately before the tube is inserted into the gap, or a previously deformed tube may be prepared.

  Next, the tube is fixed in the gap 27, and the gap is sealed (step S4). The deformed fluororesin tube 50 exerts a force to restore the cross section to a circular shape due to its elasticity, so that the gap where the side wall is in contact with the side wall of the fluororesin tube 50 is allowed to stand for a certain period of time. A force is applied toward the wall surface forming 27. As a result, the fluororesin tube 50 securely seals the gap 27, and the fluororesin tube 50 is fixed in the gap 27 by the frictional force generated between the fluororesin tube 50 and the wall surface forming the gap 27. Is done. In order to fix the fluororesin tube 50 to the gap 27 in a shorter time, the fluororesin tube 50 may be heated. For example, by irradiating hot air with a dryer or the like, the deformed tube tries to restore the original shape in a shorter time, and as a result, is fixed in the gap 27 in a shorter time. In addition, restoration of the deformed tube may be promoted by sending an inert gas such as air or nitrogen to the hollow portion of the fluororesin tube 50 and applying pressure from the inside. It is more effective when the temperature of the inert gas is high. It should be noted that the tube 50 fixed in the gap 27 by the restoring force does not have a crushed tip as shown in FIG. 4 and has an elliptical cross section, or crushed as shown in FIG. The teardrop shape is maintained with the tip remaining, without being restored until the tip disappears. Further, as described above, in order to more reliably seal the gap 27 with the fluororesin tube 50, the fluororesin tube 50 (sealing) is provided at a position corresponding to the gap 27 inside the wafer stage WST. The support member 29 that supports the material) may be provided, and the fluororesin tube 50 may be supported by the support member 29.

  As described above, wafer stage WST of the present embodiment is manufactured through steps S1 to S4. In the present embodiment, the cross section of the fluororesin tube 50 is deformed into a teardrop shape so that the fluororesin tube 50 can be easily inserted into the gap 27. However, as shown in FIG. (Rugby ball type). For example, the vice (vise) base is arranged so that the longitudinal direction of the fluororesin tube 50 is parallel to the longitudinal direction of the fluororesin tube 50, and a part of the fluororesin tube 50 is sandwiched between the bases and the base is pressurized. Forming the tip can be repeated twice to transform it into an almond shape having two tips. Alternatively, the entire tube may be sandwiched with a vise (vise) base, and the hollow portion may be crushed so that the end surface becomes a straight line. If the deformation is within a range in which the tube can be restored, the gap can be sealed after the tube is restored.

  In the present embodiment, as a part of the manufacturing method of wafer stage WST, a method of sealing gap 27 with fluororesin tube 50 as a sealing material has been described. However, part of the maintenance method of exposure apparatus EX As a result, the fluororesin tube 50 that seals the gap 27 can be replaced. For example, when the fluororesin tube 50 deteriorates due to the use of the exposure apparatus EX, the deteriorated fluororesin tube 50 is taken out as a part of the maintenance method of the exposure apparatus EX, and then the gap 27 is formed by the above-described method. Seal with a new fluororesin tube 50. The water repellent plate 28a is a replaceable part and is replaced during maintenance of the exposure apparatus EX. At this time, the fluororesin tube 50 may be replaced at the same time. In this case, after replacing the water repellent plate 28a with a new part, the gap 27 is sealed with a new fluororesin tube 50 in the same manner as described above.

<Exposure method>
Next, a method for immersion exposure of the wafer W using the exposure apparatus EX described above will be described. The main controller 20 controls the local liquid immersion device 8 to fill the optical path space of the exposure light IL between the projection optical system PL and the wafer W with the liquid Lq via the nozzle unit 32 and fill the wafer W with the liquid Lq. A liquid immersion region 14 is formed. Main controller 20 controls illumination system 10, reticle stage RST, and wafer stage WST, so that exposure light IL that has passed through reticle R is immersed in liquid Lq for immersion between projection optical system PL and wafer W, and projection optics. By irradiating the wafer W through the system PL, a pattern image of the reticle R is projected onto the wafer W by a step-and-scan method.

  For example, when the edge of the wafer W is exposed during or before the immersion exposure, the immersion area 14 extends over the water repellent plate 28a and the grating plates 28b to 28e. At this time, the immersion liquid Lq constituting the immersion area 14 comes into contact with the water-repellent plate 28a, the grating plates 28b to 28e and the fluororesin tube 50 disposed in the gap 27 formed therebetween. Since the gap 27 is sealed by the fluororesin tube 50, the immersion liquid Lq does not enter the stage. Further, since the fluororesin tube 50 is water repellent, the immersion liquid does not remain on the fluororesin tube 50 and in the recess 51 formed by the fluororesin tube 50 and the wall surface that defines the gap 27. Furthermore, from the fluororesin tube 50, the elution of impurities into the immersion liquid is extremely small, and exposure failure due to impurities can be prevented. The fluororesin tube 50 has high durability against ArF excimer laser, which is deep ultraviolet light used for exposure light, and can function as a sealing material while maintaining water repellency for a long period of time.

[Second Embodiment]
As shown in FIG. 8, the exposure apparatus of this embodiment has the same configuration as that of the first embodiment except that a tape 150 is used as a sealing material. In addition, the same number is attached | subjected to the same member as 1st Embodiment, and the description is abbreviate | omitted.

  The tape 150 includes a metal foil 151, an adhesive layer 153 provided on one surface of the metal foil 151, and a fluororesin layer 152 provided on the other surface of the metal foil 151. The gap 27 is affixed to the surface of the stage so as to cover the gap 27, and the gap 27 is sealed.

  Examples of the fluororesin used for the fluororesin layer 152 include those equivalent to the fluororesin that is the material of the fluororesin tube used in the first embodiment. In particular, PFA, PTFE, and FEP are preferable because they have high laser durability and little elution of impurities into the immersion liquid.

  The metal foil 151 preferably serves as a base material for the tape 150, has laser durability, and has little elution of impurities into the immersion liquid. As such a material, for example, titanium foil, titanium alloy foil, tantalum foil or tantalum alloy foil is preferable.

  It is preferable that the adhesive layer 153 also has less outflow of impurities into the immersion liquid, and preferably has less outgas so as not to contaminate other members. Further, since the adhesive layer 153 is shielded from the laser light by the metal foil 151, laser durability is not necessary. As such a material, for example, an acrylic adhesive layer, an epoxy adhesive layer, and the like are preferable.

  The width and length of the tape 150 can be appropriately selected in accordance with the size of the gap 27 so that the gap 27 can be sufficiently covered and sealed, but from the viewpoint of handling and workability, the width is 0.3 cm. It is preferable to set it to -1.0cm and length 5cm-20cm. Further, in order to reliably shield the adhesive layer 153 from the laser beam and avoid the contact of the adhesive layer 153 with the immersion liquid as much as possible, the width of the adhesive layer 153 is about 0.1 to 1 mm narrower than the metal foil 151. As shown in FIG. 8, it is preferable that both end portions of the adhesive layer 153 are arranged inside the both end portions of the metal foil 151. The thickness of the metal foil 151 that is the base material of the tape 150 is preferably 10 to 50 μm so that flexibility with good workability can be obtained. Further, the total thickness of the tape 150 is the same as that of the tape 150 and the surface of the stage. The thickness is preferably 10 to 30 μm so that no liquid remains at the step.

  Since the tape 150 seals the gap 27 from above (from the outside of the wafer table WTB), the gap 27 with a non-constant width D can be effectively sealed. Further, since the water repellent fluororesin layer 152 is provided on the surface of the tape 150, the immersion liquid does not remain even if the immersion liquid passes thereover. Furthermore, since the tape 150 is made of a material that does not elute impurities into the immersion liquid as described above, exposure failure due to impurities eluted into the immersion liquid can be prevented. The tape 150 has high durability against ArF excimer laser light, which is deep ultraviolet light used for exposure light, and functions as a sealing material while maintaining water repellency for a long period of time.

  The tape 150 can be manufactured as follows, for example. First, a metal foil 151 is prepared, and a fluororesin layer 152 is formed on one surface thereof. As the metal foil, for example, a titanium foil such as TP270C or TP340C (JIS number) or a titanium alloy foil such as TP270PdC or TP270PdC (JIS number) can be used. The fluororesin layer can be formed, for example, by vapor deposition such as PFA, PTFE, and FEP, and wet coating such as CYTOP (Asahi Chemical) and TEFLON-AF (DuPont). In order to improve the laser durability of the fluororesin layer 152 after the formation of the fluororesin layer 152, heating may be performed at 120 to 200 ° C. as necessary. Next, the adhesion layer 153 is formed on a surface different from the surface on which the fluororesin layer 152 of the metal foil 151 is formed (the back surface of the surface on which the fluororesin layer 152 is formed). For example, an acrylic double-sided tape can be used as the adhesive layer 153. In addition, when the fluororesin layer is formed on the surface of the metal foil by dip coating, the fluororesin layer is formed on both surfaces of the metal foil. In this case, the fluororesin layer is formed only on one side of the metal foil. An adhesive layer is formed in a laminated form.

  The tape 150 manufactured by the above method is used for the surface of the wafer stage WST through the adhesive layer 153 so as to cover the gap 27 in the manufacturing process of the wafer stage WST of the exposure apparatus EX or during maintenance of the exposure apparatus EX. The gap 27 is sealed.

  The exposure apparatus EX in which the gap 27 is sealed with the tape 150 can perform immersion exposure in the same manner as in the first embodiment. During the immersion exposure, the immersion liquid constituting the immersion area 14 contacts the water repellent plate 28a, the grating plates 28b to 28e, and the tape 150 disposed on the gap 27 formed therebetween. 27 is sealed with the tape 150, so that the immersion liquid can be prevented from entering the inside of the stage. Further, since the surface of the tape 150 is water repellent, the immersion liquid does not remain on the surface of the tape 150. In addition, since the thickness of the tape 150 is sufficiently thin, the immersion liquid does not remain on the level difference between the stage surface and the tape 150. Further, the elution of impurities from the tape 150 into the immersion liquid is very small, and exposure failure due to impurities can be prevented. Further, the tape 150 has high durability against ArF excimer laser, which is deep ultraviolet light used for exposure light, and can function as a sealing material while maintaining water repellency for a long period of time.

[Third Embodiment]
As shown in FIGS. 9 and 10, the exposure apparatus of this embodiment has the same configuration as that of the first embodiment except that a tube 250 is used as a sealing material. In addition, the same number is attached | subjected to the member which is common in 1st Embodiment, and the description is abbreviate | omitted.

  The sealing material of the present embodiment is a member obtained by bending a sheet-like substrate so that a hollow portion is formed, and the outer surface of the member is formed of a fluororesin. In this embodiment, as such a member, a pipe 250 made of a metal foil 251 provided with a fluororesin layer 252 on the outer surface is used. The cross section perpendicular to the longitudinal direction of the tube 250 of the present embodiment is a teardrop shape having a crushed tip 253 and a rounded end 254. The tube 250 is installed in the gap 27 along the gap 27, that is, in a direction in which the longitudinal direction thereof is substantially parallel to the surface of the stage and with the tip 253 facing the inside of the stage. Seal.

  For the metal foil 251 constituting the tube 250 and the fluororesin layer 252 formed on the outer surface thereof, the same material as the metal foil and fluororesin layer used for the sealing material of the second embodiment can be used. Similar to the sealing material of the second embodiment, the tube 250 is in contact with the immersion liquid and is irradiated with laser light, so that there is little elution of impurities into the immersion liquid and laser durability. It is preferable to have properties. From such a viewpoint, the metal foil is preferably a titanium foil, a titanium alloy foil, a tantalum foil or a tantalum alloy foil, and the fluororesin layer is preferably PFA, PTFE or FEP.

  The maximum width D250 of the width of the cross section perpendicular to the longitudinal direction of the tube 250 and substantially parallel to the surface of the stage is such that the tube 250 can seal the gap 27 as described above. It is larger than the maximum value of the width D of 27, and 0.30 mm to 0.34 mm is preferable from the viewpoint of handling and workability. Moreover, it is preferable that the thickness d250 of the pipe | tube 250 is 5 micrometers-30 micrometers from a viewpoint of rigidity. Further, in the cross section perpendicular to the longitudinal direction of the tube 250, the length a from the distal end portion 253 to the end portion 254 and the length b in the longitudinal direction of the tube 250 are respectively from the viewpoint of workability and linearity maintenance. The length a is preferably 3 mm to 10 mm, and the length b is preferably in the range of 5 cm to 20 cm.

  The tube 250 is hollow, and in particular, the vicinity of the rounded end portion 254 is elastic. Therefore, the tube 250 fits flexibly to the wall surface forming the gap 27 and effectively seals the gap 27 having a non-constant width D. Further, since the surface of the tube 250 is provided with the water-repellent fluororesin layer 252, the liquid for immersion remains in the recess 51 formed by the surface of the tube 250 and the wall surface that defines the tube 250 and the gap 27. There is nothing. Further, the tube 250 has very little impurity elution into the immersion liquid, and can prevent exposure failure due to the impurities eluted into the immersion liquid. Further, it is highly durable against ArF excimer laser, which is deep ultraviolet used for exposure light, and functions as a sealing material while maintaining water repellency for a long period of time.

  In order to reduce the possibility of immersion liquid remaining around the tube 250, the tube 250 is disposed on both sides of the tube 250 and is in contact with the tube 250. 28e is preferably flush with the virtual plane 26, that is, flush with the virtual plane 26. To be flush with the virtual plane 26 means that the portion 255 of the side surface of the tube 250 that protrudes most toward the outside of the wafer stage WST is arranged so as to contact the virtual name surface 26. The tube 250 is located at a specific position in the gap 27 by the frictional force with the wall surface forming the gap 27. In order to fix the position and ensure installation in the gap 27, the wafer 250 A support member 29 that supports the tube 250 (sealing material) may be provided at a position corresponding to the gap 27 inside the stage WST.

  The tube 250 can be manufactured as follows, for example. First, a rectangular metal foil 251 is prepared, and a fluororesin layer 252 is formed on one surface thereof. The metal foil 251 can be the same as the metal foil 151 used in the second embodiment, and the fluororesin layer 252 is also formed by the same method as the fluororesin layer 152 used in the second embodiment. be able to. Next, both opposite ends of the rectangular metal foil 251 are bent so that a tube (cylinder) having the surface on which the fluororesin layer 252 is formed as an outer surface is bonded, and the both ends are bonded. At this time, by providing the bonding surfaces at both ends on the same surface of the metal foil 251 (the surface on which the fluororesin layer 252 is not formed), the cross section of the tube 250 is a tear with the bonded portion crushed at the tip 253. Form a mold. The metal foil 251 can be bonded by, for example, spot welding, and the pipe 250 has a plurality of spot welds 255 as shown in FIG. In addition, when the fluororesin layer 252 is formed on the surface of the metal foil 251 by dip coating, the fluororesin layer 252 is formed on both surfaces of the metal foil 251. 250 may be formed.

  The tube 250 manufactured by the above method has a longitudinal direction substantially parallel to the surface of the stage in the manufacturing process of the wafer stage WST of the exposure apparatus EX or during maintenance of the exposure apparatus EX, and The tip 253 is placed in the gap 27 with the inside of the stage facing the inside, and the gap 27 is sealed.

  The exposure apparatus EX in which the gap 27 is sealed with the tube 250 can perform immersion exposure by the same method as that described in the first embodiment. During the immersion exposure, the immersion liquid constituting the immersion area 14 comes into contact with the water repellent plate 28a, the grating plates 28b to 28e, and the pipe 250 disposed in the gap 27 formed therebetween. Is sealed by the tube 250, so that the immersion liquid can be prevented from entering the inside of the stage. In addition, since the surface of the tube 250 is water-repellent, no immersion liquid remains on the surface of the tube 250. Further, the elution of impurities from the tube 250 into the immersion liquid is extremely small, and exposure failure due to impurities can be prevented. The tube 250 has high durability against ArF excimer laser, which is deep ultraviolet used for exposure light, and can function as a sealing material while maintaining water repellency for a long period of time.

  In addition, the sheet-like base material of this embodiment is not restricted to metal foil, For example, a fluororesin sheet | seat can also be used. In this case, since the outer surface of the member is made of fluororesin, it is not necessary to separately provide a fluororesin layer on the outer surface. Moreover, in this embodiment, although the member (sealing material) which closed the edge part of metal foil by spot welding and used it as the pipe shape was used, the member (sealing material) of this embodiment is not necessarily a pipe shape. There is no need. For example, the member which bent the fluororesin sheet | seat so that a hollow part may be formed, and formed the curved surface part may be sufficient, and the edge part of a fluororesin sheet | seat does not need to be closed. Such a member is also installed in the gap 27 with the curved surface portion formed by the bending of the member facing the outside of the stage, and the gap 27 can be sealed. The same effect is produced.

  In the first to third embodiments described above, the water-repellent plate 28a and the sealing materials 50, 150, and 250 are separate parts, but the water-repellent plate and the sealing material are integrated into one piece. It may be a part. For example, the side surface of the fluororesin tube 50 is connected to the four sides of the rectangular outer periphery of the water repellent plate 28a. The water repellent plate 28a is a replaceable part and is replaced during maintenance of the exposure apparatus EX. However, when the water repellent plate 28a and the fluororesin tube 50 are integrated, the water repellent plate is replaced and the fluororesin tube is replaced. 50 gaps 27 can be installed at a time, and work efficiency is good.

  In the first to third embodiments, the aspect of sealing the gap 27 generated between the water repellent plate 28a and the grating plates 28b to 28e, which is a component on the wafer table WTB (wafer stage WST), has been described. The gap sealed by the sealing material is not limited to this. For example, in the exposure apparatus EX, a measurement stage (not shown) that can move in the X and Y directions independently of the wafer stage WST is placed on the upper surface 12a of the base board 12 as described above. A plurality of parts such as an aerial image measurement device that measures the imaging characteristics of the projection optical system PL are arranged on the measurement stage, for example, but a gap generated between these parts, or between these parts and the measurement stage. The generated gap may be sealed with the sealing material described in the above embodiment. Moreover, the sealing material demonstrated by the above-mentioned embodiment can also seal the clearance gap which arises between the nozzle unit 32 and the lens-barrel 40 in exposure apparatus EX, for example. By sealing such a gap, the immersion liquid can be prevented from entering the exposure apparatus, and the exposure apparatus can be protected electrically and mechanically.

  As a further example, FIG. 11 shows wafer stage WST2 holding wafer W2. Unlike wafer stage WST described in the first to third embodiments, wafer stage WST2 has reference member 300, illuminance unevenness sensor 400 and aerial image measurement sensor 500 instead of water repellent plate 28a and grating plates 28b to 28d. Is provided. Gaps K, L, and N are formed between the reference member 300, the illuminance unevenness sensor 400, the aerial image measurement sensor 500, and the surface of the wafer stage WST2, respectively. These gaps K, L, and N can also be sealed using the sealing material described in the above embodiment. Thereby, it is possible to achieve the same effect as the above-described embodiment, such as preventing the immersion liquid from entering the exposure apparatus.

  In addition, an electronic device (or a micro device) such as a semiconductor device can be manufactured using the exposure apparatus EX or the exposure method of the above embodiment. As shown in FIG. 12, the electronic device has a step S11 for designing the function and performance of the electronic device, a step S12 for producing a reticle (mask) based on this design step, and a substrate (wafer) as a base material of the device. Step S13 for producing and applying a resist, a step of exposing a reticle pattern to a substrate (photosensitive substrate) by the exposure apparatus (exposure method) of the above-described embodiment, a step of developing the exposed substrate, and heating of the developed substrate ( It is manufactured through a substrate processing step S14 including a curing and etching process, a device assembly step (including processing processes such as a dicing process, a bonding process, and a packaging process) S15, an inspection step S16, and the like.

  In other words, the device manufacturing method transfers the reticle pattern image onto the substrate (wafer) using the exposure apparatus EX (exposure method) of the above embodiment, and the pattern image transferred to the device. Processing the substrate based on the image of the pattern (development, etching, etc. in step S14).

  The present invention can be applied to a step-and-repeat type projection exposure apparatus (stepper or the like) in addition to the above-described step-and-scan type scanning exposure type projection exposure apparatus (scanner).

  The present invention is not limited to an exposure apparatus for manufacturing a semiconductor device, but is used for manufacturing a display including a liquid crystal display element and a plasma display. Applicable to exposure equipment that transfers device patterns used in ceramics onto ceramic wafers, as well as exposure equipment used to manufacture imaging devices (CCD, etc.), organic EL, micromachines, MEMS (Microelectromechanical Systems), DNA chips, etc. can do. As described above, the present invention is not limited to the above-described embodiment, and various configurations can be taken without departing from the gist of the present invention.

  EX ... exposure apparatus, R ... reticle, W ... wafer, WTB ... wafer table, WST ... wafer stage, 20 ... main controller, 50, 150, 250 ... sealing material, 28a ... water repellent plate, 28b-28e ... grating Board

Claims (15)

An exposure apparatus that exposes a substrate through a liquid,
A stage whose surface is assembled from a plurality of members;
An exposure apparatus comprising a sealing material that seals at least one gap between the members present on the surface of the stage. The sealing material is an elongated fluororesin tube;
The exposure apparatus according to claim 1, wherein the fluororesin tube seals the gap along the gap.   3. The exposure apparatus according to claim 2, wherein a cross section perpendicular to the longitudinal direction of the fluororesin tube has an elliptical shape or a teardrop shape. The sealing material is
Metal foil,
An adhesive layer provided on one surface of the metal foil;
A tape comprising a fluororesin layer provided on the other surface of the metal foil;
The exposure apparatus according to claim 1, wherein the tape is attached to the surface of the stage via the adhesive layer so as to cover the gap. The sealing material is a member obtained by bending a sheet-like base material so that a hollow portion is formed,
The outer surface of the member is formed of fluororesin,
2. The exposure apparatus according to claim 1, wherein the member seals the gap along the gap with a curved surface formed by bending the member facing the outside of the stage. 3. The sheet-like base material is a metal foil, and a fluororesin layer is provided outside the member,
The cross section perpendicular to the longitudinal direction of the member is a teardrop shape having a crushed tip and a rounded end,
The exposure apparatus according to claim 5, wherein the member seals the gap along the gap with the tip portion directed toward the inside of the stage.   The fluororesin that forms the fluororesin tube, the fluororesin layer or the outer surface of the member is made of polytetrafluoroethylene (PTFE), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA) and tetrafluoro. The exposure apparatus according to claim 2, comprising any one of ethylene / hexafluoropropylene copolymer (FEP).   The exposure apparatus according to claim 4 or 6, wherein the metal foil includes any one of titanium, a titanium alloy, tantalum, and a tantalum alloy.   The exposure apparatus according to claim 1, wherein a support member that supports the sealing material is provided at a position corresponding to the gap inside the stage.   The exposure apparatus according to claim 1, wherein the stage is a substrate stage.   The exposure apparatus according to claim 1, wherein the members are a water repellent plate and a grating plate. A method of manufacturing a stage mounted on an exposure apparatus that exposes a substrate through a liquid,
Assembling the stage from multiple members,
Preparing an elongated fluoropolymer tube;
Inserting the elongated fluororesin tube along the gap into the gap between the members present on the surface of the assembled stage in contact with the liquid; and inserting the fluororesin tube into the gap A method for manufacturing a stage, comprising fixing the gap and sealing the gap. Furthermore, before inserting the fluororesin tube into the gap, a cross section perpendicular to the longitudinal direction of the fluororesin tube has a teardrop shape having one tip portion or an almond shape having two tip portions. Including deforming the fluororesin tube so as to be,
Inserting the fluororesin tube into the gap includes inserting the fluororesin tube into the gap in a direction in which one of the deformed fluororesin tubes faces the inside of the stage. The manufacturing method of the stage of Claim 12 containing. A support member for supporting the fluororesin tube is provided at a position corresponding to the gap inside the stage,
The stage manufacturing method according to claim 12 or 13, wherein fixing the fluororesin tube into the gap includes supporting the fluororesin tube by the support member.   A device manufacturing method using the exposure apparatus according to claim 1.

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