JP2007025085A - Exposure device, optical element array and multispot beam generator, and device manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exposure device which can make a footprint narrow and can be made compact, lightweight, and low-cost. <P>SOLUTION: A pattern projection unit 14 supported by support members 24 and 26 over a substrate P across a clearance in the gravitational direction is driven by a driving system in a specified direction. A pattern is formed on the substrate by the pattern projection unit 14 during the driving (or in synchronism with the driving) and thus the formation of the pattern in an area of specified size on the substrate, i.e. exposure becomes possible. The substrate (substrate holding member) is fixed and the pattern projection unit 14 moves, so the need for a large and heavy surface plate supporting a stage etc., holding the substrate is eliminated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an exposure apparatus, an optical element array, a multi-spot beam generator, and a device manufacturing method. More specifically, the present invention relates to an exposure apparatus used in a lithography process in manufacturing a liquid crystal display element (liquid crystal panel) and the like. The present invention relates to an optical element array and a multi-spot beam generator suitable for use in a pattern forming unit, and a device manufacturing method using the exposure apparatus.

  Conventionally, in a lithography process for manufacturing a microdevice such as a semiconductor element or a liquid crystal display element, a photosensitive agent such as a resist is applied to a pattern formed on a mask (reticle, photomask, etc.) via a projection optical system. Step-and-repeat projection exposure apparatuses (steppers) that transfer onto plates (glass plates, wafers, etc.), step-and-scan projection exposure apparatuses, and the like are used.

  By the way, plates, particularly glass plates, have gradually become larger with the increase in size of liquid crystal display elements, and in recent years, plates having a size of 1 m square or more have come to be used relatively frequently. In the future, it is a certain situation that the glass plate will further increase in size. Moreover, the mask has also increased in size with the increase in the size of the glass plate. However, if the required pattern rule (practical minimum line width) is the same, the same degree of flatness is required regardless of the size of the mask, and a large mask can bend and swell as much as a small mask. It is necessary to suppress. Therefore, in the case of a large mask, it is necessary to make it significantly thicker than that of a small mask, which causes an increase in cost. In particular, an expensive quartz glass is used for a mask used in the manufacture of, for example, a TFT (Thin Film Transistor) or the like, and thus cost increase due to an increase in size is a particular problem.

  Recently, in order to improve such inconvenience, a maskless type capable of forming a device without using an expensive mask regardless of the size of the device pattern (without using a mask which is a fixed pattern master). A scanning projection exposure apparatus has been proposed (see, for example, Patent Document 1). The scanning projection exposure apparatus described in Patent Document 1 includes a variable pattern generation device that forms a transfer pattern, a projection optical system that projects a transfer pattern generated by the variable pattern generation device onto a photosensitive substrate, And a substrate stage for scanning the photosensitive substrate. The variable pattern generation device changes a transfer pattern generated in the variable pattern generation device in synchronization with scanning of the substrate stage, and the projection optical system adjusts an image of the transfer pattern. It has a mechanism. For this reason, according to the scanning projection exposure apparatus described in Patent Document 1, it is possible to easily generate a desired pattern by changing the transfer pattern generated in the variable pattern generation apparatus in synchronization with the scanning of the substrate stage. Can do. Further, unlike an exposure apparatus that uses a conventional mask, it is not necessary to provide a mask stage, so that the cost of the exposure apparatus can be reduced and the size can be reduced, and the adjustment mechanism that the projection optical system adjusts the image of the transfer pattern Therefore, it is possible to accurately project an image of a transfer pattern generated by the variable pattern generation device.

  However, the size of the glass plate is increasing with each generation, and now it has reached the seventh generation of 1870 mm × 2200 mm, and in the future eighth generation, it will be increased to a size exceeding 2 m square. Considering the case where the above-described large glass plate is placed on an apparatus including a substrate stage for scanning a photosensitive substrate, such as a maskless type scanning exposure apparatus disclosed in Patent Document 1 or the like, The stage base (surface plate) that supports the substrate stage is enlarged and weighted. For example, even if a 7th generation glass plate is used, the surface plate must have a long side length of 4 m or more. The weight reaches 10 [t]. In such a case, in addition to increasing the size and weight of the exposure apparatus, it has the disadvantage that it is difficult to transport (transport) the surface plate. In addition, because the surface plate needs to be manufactured as a single piece due to its nature, it is very difficult to manufacture and process, resulting in a significant increase in manufacturing cost.

JP 2004-327660 A

  From a first aspect, the present invention is an exposure apparatus that exposes a substrate to form a predetermined pattern on the substrate, a substrate holding member that holds the substrate substantially flat; and a pattern on the substrate. A pattern forming portion to be formed; provided in the pattern forming portion so as to face the substrate held by the substrate holding member; and at least a part of the pattern forming portion with respect to the surface of the substrate in a predetermined direction with respect to the direction of gravity A support member supported via a clearance; and driving the pattern forming portion, which is supported by the support member via the predetermined clearance with respect to a direction of gravity along the surface of the substrate, along the surface of the substrate. And a drive system.

  According to this, since the pattern forming unit, which is supported by the support member with respect to the substrate through the predetermined clearance with respect to the direction of gravity, is driven in the predetermined direction by the drive system, By forming a pattern on the substrate in the pattern forming unit (synchronously with the driving thereof), it is possible to form a pattern in a predetermined area of the substrate, that is, to perform exposure. Further, since it is not necessary to provide a mask stage, the cost and size of the exposure apparatus can be reduced. In addition, since the substrate (substrate holding member) is fixed and the pattern forming unit can be moved, a large and heavy surface plate that supports a stage or the like for holding the substrate becomes unnecessary. Therefore, compared with the conventional maskless type scanning projection exposure apparatus, it is possible to considerably reduce the footprint, reduce the size and weight, and reduce the cost. In addition, since the small and lightweight pattern forming unit moves, it is possible to suppress vibration caused by the reaction force of the driving force during the movement, and to form the pattern on the substrate accurately by this vibration suppression. Is possible.

  From a second viewpoint, the present invention provides a first straight line in the third axis direction that forms a predetermined angle with respect to the second axis in a two-dimensional plane including the first axis and a second axis perpendicular thereto. A first row of optical element groups including a plurality of optical elements arranged at a predetermined pitch, and the predetermined pitch on a second straight line spaced from the first straight line by a predetermined distance in the first axial direction; And a second row of optical element groups including a plurality of optical elements arranged at a position including at least a formed plate, and forming a spot on a predetermined surface when each of the optical elements is illuminated with illumination light An optical element array characterized by being a phase type diffractive optical element.

  According to this, in the optical element array, a plurality of phase type diffractive optical elements are arranged at a predetermined pitch p on a first straight line and a second straight line that are parallel to each other and have a predetermined angle with respect to the second axis. Therefore, the optical element array can be moved relative to the predetermined surface in the second axis direction by setting the pitch to a dimension corresponding to the shape of the spot formed on the predetermined surface by each diffractive optical element. Thus, it is possible to expose a region of a predetermined area on the predetermined surface with a spot without a gap.

  According to a third aspect of the present invention, there is provided a multi-spot beam generator for forming a plurality of spot beams on a predetermined surface, the optical element array of the present invention; and each optical element constituting the optical element array. A multi-spot beam generator comprising: a spatial light modulator that realizes incidence and non-incidence of individual illumination light on the element.

  According to this, the multi-spot beam generator of the present invention is moved relative to the substrate to be exposed in the second axis direction, and at that time, individual illumination for each optical element constituting the optical element array by the spatial light modulator By making light incident and non-incident, the arrangement of spots formed on the substrate surface, that is, the pattern shape, arrangement, and the like can be changed, so that a desired pattern can be easily formed on the substrate. . In this case, it is possible to perform exposure with a uniform integrated energy amount (exposure dose amount) distribution over the entire area of a predetermined area on the substrate.

  From a fourth aspect, the present invention is an exposure apparatus that exposes a substrate to form a predetermined pattern on the substrate, a substrate holding member that holds the substrate substantially flat; and the multi-spot beam of the present invention A pattern forming unit that includes a generator and exposes the substrate with a plurality of spot beams by the multi-spot beam generator to form a pattern; and drives at least one of the substrate holding member and the pattern forming unit to It is a 2nd exposure apparatus provided with the drive system which carries out relative scanning to a biaxial direction.

  According to this, the spatial light modulator inside the multi-spot beam generator constituting the pattern forming unit is controlled in synchronization with the pattern forming unit being scanned relative to the substrate in the second axis direction by the drive system. Thus, a desired pattern can be easily formed on the substrate. Further, it is not necessary to provide a mask stage that is necessary when using a mask that is an object pattern.

  In the lithography process, by exposing the substrate using the first and second exposure apparatuses of the present invention, a highly integrated device can be formed with high accuracy. Therefore, from another viewpoint, the present invention can be said to be a device manufacturing method including a lithography step of exposing a substrate using either the first exposure apparatus or the second exposure apparatus of the present invention.

<< First Embodiment >>
A first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 schematically shows a configuration of an exposure apparatus 100 according to the first embodiment.

  An exposure apparatus 100 shown in FIG. 1 is placed on a support plate (base or surface plate) 10 installed horizontally (parallel to the XY plane) 10 on a floor surface F of a clean room. An upper surface of a plate holder 12 that can be moved relative to the support plate 10 in the XY plane, and a glass plate (hereinafter abbreviated as “plate”) P held on the plate holder 12 by vacuum suction or the like. The pattern projection unit 14 disposed above the plate P and supported by a support member provided at the bottom thereof with respect to the upper surface of the plate P via a predetermined clearance (for example, about several μm), and the pattern projection unit 14 is mounted on the plate P A projection unit drive system for driving in the XY plane along the upper surface of the light source, and the follow-up light connected to the pattern projection unit 14 via the cable portion 16 And a unit 18, and follow-up unit driving system for driving to follow the tracking optical unit 18 in the pattern projection unit 14.

  The plate holder 12 is supported on the upper surface of the support plate 10 via a predetermined clearance (for example, about several μm) by a large number of static gas bearings, for example, air bearings (not shown) provided on the bottom surface. Yes. Of course, the plate holder 12 may be placed on the support plate 10 via a large number of balls or rollers.

  Inside the plate holder 12, an armature unit 22 including a coil array composed of a large number of coils arranged at predetermined intervals in the XY two-dimensional direction is provided. The coil array constituting the armature unit 22 includes a Z driving coil in addition to the X driving coil and the Y driving coil.

  The pattern projection unit 14 has a first partial optical system portion 14A having a first support member 24 fixed to the bottom thereof, a second partial optical system portion 14B fixed to the + X side of the first partial optical system portion 14A, And a bending mirror part 14C provided on the upper side of the second partial optical system part 14B, and a connection part 14D between the second partial optical system part 14B and the bending mirror part 14C. In this case, a second support member 26 having a U-shape in plan view is fixed to the end surface on the + X side and the both end surfaces in the Y-axis direction of the bottom of the second partial optical system portion 14B. That is, the entire pattern projection unit 14 including the bending mirror portion 14C, the connection portion 14D, the first partial optical system portion 14A, and the second partial optical system portion 14B includes the first and second support members 24, 26 is levitated and supported above the upper surface of the plate P by a clearance of about several μm. Here, the first and second support members 24 and 26 are each constituted by a casing having a plurality of gas static pressure bearings, for example, air bearings, and a magnetic pole unit including a magnet array on its bottom surface. The magnetic pole unit, together with the armature unit 22 described above, drives the pattern projection unit 14 freely in the X-axis direction and the Y-axis direction, as well as the Z-axis direction, the θx direction (rotation direction around the X axis), and the θy direction (X An actuator, for example, a magnetically levitated planar motor 23 (see FIG. 5) that is finely driven in the rotation direction around the axis) and the θz direction (the rotation direction around the Z axis) is configured. As the flat motor 23, for example, one having a configuration disclosed in Japanese Patent Application Laid-Open No. 2000-852744 (corresponding US Pat. No. 6,304,320) can be adopted. A projection unit drive system is configured.

  The following optical unit 18 includes a housing 28 and a light source 30 accommodated in the housing 28. As the light source 30, for example, a high-power ultraviolet light-emitting diode (UV-LED) having a center wavelength of 365 nm that is the same wavelength as the i-line is used. However, the present invention is not limited thereto, and a CW laser that outputs continuous light having wavelengths of 400 nm, 473 nm, 488 nm, 491 nm, 514 nm, 515 nm, and 532 nm may be used as a light source. Of course, an ultrahigh pressure mercury lamp may be used as a light source, and the i-line (365 nm) may be extracted by a wavelength selection filter. In the present embodiment, as will be described later, an active mask made of a transmissive liquid crystal display element is used. Therefore, it is desirable to use a light source that outputs illumination light having a wavelength of 350 nm to 600 nm. This is because it is desirable to set the wavelength longer than 350 nm so that the illumination light from the light source can easily pass through the transmissive liquid crystal display element, and in order not to reduce the resolution unnecessarily, the wavelength of the illumination light is set to 600 nm. This is because it is desirable to make the wavelength shorter. For example, a plurality of lights having different wavelengths or broadband light within the above wavelength range may be used as the illumination light for exposure. Further, it is preferable to take heat countermeasures such as providing a cooling device in the follow-up optical unit 18 so that heat generated from the follow-up optical unit 18 (light source 30 or the like) is not transmitted to the pattern projection unit 14.

  The folding mirror portion 14C has an opening that forms a passage for illumination light on the + Y side wall, and a housing 32 having a bottom surface (lower surface) opened, and a horizontal plane within the housing 32. There is a bending mirror M that is obliquely installed at an angle of 45 ° and that bends the optical path of the illumination light that is output from the tracking optical unit 18 and incident through the opening, vertically downward.

  The connecting portion 14D has a frame body 34 whose upper surface and lower surface are opened, and an active mask 36 capable of generating a variable pattern is held in the frame body 34 in parallel with the XY plane. In the present embodiment, the active mask 36 is an electronic device composed of a transmissive liquid crystal display (LCD) which is a kind of non-light-emitting image display element that is illuminated with illumination light to generate an image (pattern). A mask is used. The active mask 36 is provided with a trapezoidal effective area corresponding to an exposure area IA described later (an irradiation area of illumination light on the plate P via a projection optical system described later (see FIG. 4)). .

  The second partial optical system portion 14B includes a housing 38 having both an upper surface and a lower surface that are open, and an opening formed on a surface on the −Y side. The end surface on the + Y side at the bottom of the housing 38 and the X axis The aforementioned second support member 26 is fixed to both end surfaces in the direction. The first partial optical system portion 14A has a housing 40 with an opening formed on the surface on the + Y side. The first support member 24 is fixed to the bottom of the housing 40. A projection optical system that projects a pattern formed in the effective area of the active mask 36 onto the plate P is accommodated in the housings 38 and 40.

  More specifically, as shown in FIG. 3, a right-angle prism Pr is accommodated in the housing 38. The right-angle prism Pr is a state in which the first reflecting surface P1r composed of one inclined surface sandwiching a right angle and the second reflecting surface P2r composed of the other inclined surface sandwiching the right angle are both inclined by 45 ° with respect to the XY plane and They are arranged with their right-angled vertices facing in the -Y direction (viewed from the + X direction).

  Further, inside the housing 40, in order from the right prism Pr (first reflecting surface P1r) side, a refractive optical system K1 having a positive refractive power, and a concave reflecting mirror M1 having a concave surface directed to the right prism Pr side, and Is arranged. The refractive optical system K1 and the concave reflecting mirror M1 are arranged along the Y-axis direction, and constitute a catadioptric system having the optical axis AX1 in the Y-axis direction as a whole. The optical axis AX1 passes through the aforementioned vertex of the right-angle prism Pr. A projection optical system PL including a catadioptric system including the catadioptric system and the right-angle prism Pr described above and having the optical axis AX1 as its optical axis is configured. According to the projection optical system PL, the illumination light incident in the −Z direction from the active mask 36 is reflected in the −Y direction by the first reflecting surface P1r of the right-angle prism Pr and enters the refractive optical system K1. The illumination light incident on the refractive optical system K1 is reflected by the concave reflecting mirror M1, and the reflected light travels in the + Y direction via the refractive optical system K1 and reaches the second reflecting surface P2r of the right-angle prism Pr. The illumination light is reflected toward the −Z direction by the second reflecting surface P2r of the right-angle prism Pr and is projected onto the plate P.

  In the present embodiment, a bilateral telecentric catadioptric system that forms an equal-magnification erect image on the image plane is used as the projection optical system PL.

  As is apparent from the above description, the image field IF of the projection optical system PL is a semicircular region as shown in FIG. 4, and the image field IF is used in the image field IF in order to efficiently use the image field IF. A trapezoidal exposure area IA is set. In this case, the exposure area IA is defined by the effective area on the active mask 36 described above. However, the present invention is not limited to this. For example, a field stop is formed on a surface optically conjugate with the image plane and the surface of the active mask 36. It may be provided to define the exposure area IA.

  In this case, for example, an optical system for adjusting the magnification may be disposed below the second reflecting surface P2r of the right-angle prism Pr. However, when an optical system for adjusting the magnification is employed, an image of a transfer pattern is formed in the optical path between the active mask 36 and the first reflecting surface P1r in order to correct an image shift caused by the magnification adjustment. It is desirable to arrange at least one of a focus position correcting optical system for correcting the position (focus position) and an image shift correcting optical system. As an example of the focal position correcting optical system, a so-called wedge lens (a pair of wedge-shaped optical members configured so that the distance between the incident surface and the exit surface perpendicular to the Z axis can be adjusted) can be used. In the embodiment, the wedge lens 37 is disposed in the optical path between the active mask 36 and the first reflecting surface P1r as a focal position correcting optical system. Further, as the optical system for image shift correction, for example, a parallel flat glass plate whose tilt angle with respect to the Z axis can be adjusted can be used.

  A pair of Y sliders 44 are attached to the casing 28 of the following optical unit 18 via attachment members 42. Each Y slider 44 is attached around the Y guide 46 and has a plurality of permanent magnets arranged at a predetermined pitch along the Y-axis direction. In this case, the permanent magnets adjacent in the Y-axis direction have opposite polarities. The Y guide 46 has a longitudinal direction as the Y-axis direction, and a large number of armature coils are arranged at a predetermined pitch in the Y guide 46. That is, a moving magnet type Y that drives the following optical unit 18 attached to the Y slider 44 via the attachment member 42 in the Y-axis direction along the Y guide 46 by the pair of Y slider 44 and Y guide 46. A shaft linear motor 48 is configured.

  Here, a plurality of non-contact bearings (not shown) such as air bearings may be provided at predetermined intervals on at least a part of the surface of each Y slider 44 facing the Y guide 46.

  X-sliders 50A and 50B having a rectangular frame shape as viewed from the + X direction are fixed to one end surface and the other end surface in the longitudinal direction of the Y guide 46, respectively. One X slider 50A is attached to the outer periphery of an X guide 52A having a substantially square cross section extending in the X axis direction. That is, the X guide 52A is inserted into the opening of the X slider 50A. Armature coils are arranged at predetermined intervals along the X-axis direction on at least one of the inner surfaces of the X slider 50A.

  The X guide 52 </ b> A is supported at one end and the other end in the longitudinal direction by a support member 54 </ b> A whose lower end is fixed to the upper surface of the support plate 10. The X guide 52A has a plurality of permanent magnets arranged at predetermined intervals along the X-axis direction facing the armature coil on the outer surface thereof. In this case, adjacent permanent magnets have opposite polarities. That is, the X slider 50A and the X guide 52A constitute a moving coil type X axis linear motor 56A that drives the X slider 50A in the X axis direction along the X guide 52A.

  The other X slider 50B is configured in the same manner as the X slider 50A. Further, the other X guide 52B is configured in the same manner as the X guide 52A, and one end and the other end in the longitudinal direction thereof are respectively supported by a support member 54B whose lower end is fixed to the upper surface of the support plate 10. It is supported. Also in this case, the X slider 50B and the X guide 52B constitute a moving coil type X axis linear motor 56B that drives the X slider 50B in the X axis direction along the X guide 52B.

  Of course, moving magnet type linear motors may be used as the X-axis linear motors 56A and 56B.

  A plurality of non-contact bearings (not shown) such as air bearings may be provided at predetermined intervals on at least a part of the surface of each X slider facing the corresponding X guide.

  As described above, in this embodiment, the tracking optical unit 18 is driven in the Y-axis direction by the Y-axis linear motor 48, and the tracking optical unit 18 is integrated with the Y-axis linear motor 48 by the pair of X-axis linear motors 56A and 56B. Are driven in the X-axis direction. That is, at least a part of the drive system that drives the tracking optical unit 18 includes the X-axis linear motors 56A and 56B and the Y-axis linear motor 48.

  The driving amount of the X sliders 50A and 50B by the X axis linear motors 56A and 56B (or positional information of the X sliders 50A and 50B in the X axis direction) is a measurement sensor, for example, a linear encoder 68 (not shown in FIG. 1, see FIG. 5). ) Is measured. The measurement value of the linear encoder 68 is supplied to the main controller 80 (see FIG. 5).

  Further, the distance (interval) in the Y-axis direction between the housing 28 of the tracking optical unit 18 and the housing 32 of the bending mirror portion 14C is determined by a displacement sensor (for example, PSD (Position Sensitive Device)) fixed to the housing 28. It is measured by a laser displacement sensor 70, an eddy current displacement sensor, or a capacitance displacement sensor used) 70 (not shown in FIG. 1, see FIG. 5). The measurement value of the displacement sensor 70 is supplied to the main controller 80 (see FIG. 5).

  The positional information of the pattern projection unit 14 in the XY plane is obtained by a laser interferometer system 60 fixed to the pattern projection unit 14 via a plane mirror 58 fixed on the plate holder 12 with a predetermined resolution, for example, 0. It is always measured with a resolution of about 5 to 1 nm.

  More specifically, as shown in FIG. 2 which shows the plate holder 12 and the pattern projection unit 14 in a perspective view, the first interferometer 60A is fixed to the + X side surface of the casing 38, and the casing The second interferometer 60B is fixed to the surface of the body 38 on the −X side. At the + Y side end of the upper surface of the plate holder 12, a first plane mirror 58Y having a reflecting surface orthogonal to the Y-axis direction and facing the first interferometer 60A extends in the X-axis direction. On the −X side end, a second flat mirror 58X having a reflecting surface orthogonal to the X-axis direction is provided in the Y-axis direction so as to face the second interferometer 60B.

  The first interferometer 60A includes a light source, an optical system including a beam splitter, a detector, a reference mirror, and the like. The beam from the light source is separated into a length measuring beam and a reference beam by the beam splitter. The reflected light of the first plane mirror 58Y is irradiated to receive the reflected light, and the received reflected light and the reflected light of the reference beam from the reference mirror are coaxially combined through the optical system to interfere with each other. An interference signal corresponding to the difference between the optical path length of the reference beam and the optical path length of the measurement beam is output from the detector that has received the interference light. However, in the case of the present embodiment, the plane mirror 58Y is fixed on the plate holder 12, and the reference mirror is provided in the pattern projection unit 14 which is a moving body, so that the output from the first interferometer 60A. The interference signal is nothing but a signal corresponding to the positional information regarding the Y-axis direction of the pattern projection unit 14 (reference mirror) with reference to the reflection surface of the plane mirror 58Y.

  The second interferometer 60B includes a light source, an optical system including at least three beam splitters, a reference mirror for the X-axis direction, a reference mirror for the Y-axis direction, a detector for measuring the X-axis direction position, and for measuring the Y-axis direction position. Built-in detector. The second interferometer 60B splits the beam from the light source into two beams by the first beam splitter, and separates each beam into the length measuring beam and the reference beam by the second and third beam splitters. . The second interferometer 60B irradiates the length measurement beam separated by the second beam splitter onto the reflection surface of the first plane mirror 58Y, receives the reflected light, and receives the reflected light and the Y axis. The optical path length of the reference beam and the optical path of the length measurement beam from the detector for measuring the position in the Y-axis direction, which receives the interference light by coaxially synthesizing the reflected light from the direction reference mirror through the optical system. A first interference signal corresponding to the difference from the length is output. In addition, the second interferometer 60B irradiates the length measurement beam separated by the third beam splitter onto the reflection surface of the second plane mirror 58X to receive the reflected light, and the received reflected light and the X axis The optical path length of the reference beam and the optical path of the measuring beam are received from the X-axis direction position detector that receives the interference light by coaxially combining the reflected light from the direction reference mirror with the optical system and causing the interference. A second interference signal corresponding to the difference from the length is output. Also in this case, the first and second interference signals output from the second interferometer 60B correspond to position information regarding the Y-axis direction of the pattern projection unit 14 (reference mirror) with the reflection surface of the plane mirror 58Y as a reference. This signal is nothing but a signal corresponding to position information regarding the X-axis direction of the pattern projection unit 14 (reference mirror) with reference to the reflection surface of the plane mirror 58X.

  The length measurement axis of the first interferometer 60A and one length measurement axis of the second interferometer 60B parallel thereto are separated by the same distance from the extended line of the optical axis AX1 of the projection optical system PL to the + X side and the −X side. The other measurement axis of the second interferometer 60B passes through a straight line perpendicular to the optical axis AX1 at a point on the pattern projection center by the projection optical system PL. In addition, each measuring axis is set.

  The interference signals from the first and second interferometers 60 and 61 are supplied to the main controller 80 (see FIG. 5). The main controller 80 detects the interference signals from the interferometer 60 and the interferometer 61. On the basis of the first interference signal from the reference coordinate system (orthogonal coordinate system (X, Y) having the origin at the intersection of the extension line of the reflection surface of the plane mirror 58X and the extension line of the reflection surface of the plane mirror 58Y. )) Calculate the Y coordinate and θz rotation error (yaw amount) of the pattern projection unit 14 above. Further, main controller 80 calculates the X coordinate of pattern projection unit 14 on the reference coordinate system based on the second interference signal from interferometer 61. Here, actually, both the first interferometer 60A and the second interferometer 60B are multi-axis interferometers having a plurality of measurement axes, and the main controller 80 outputs the output signals of these interferometers 60A and 60B. The pitching amount (rotation error around the X axis (rotation error in the θx direction)) and the rolling amount (rotation error around the Y axis (rotation error in the θy direction)) of the pattern projection unit 14 are also calculated based on the above.

  As described above, a plurality of plane mirrors and interferometers are provided, but in FIG. 1, these are typically shown as the plane mirror 58 and the interferometer 60.

  In each of the interferometers 60A and 60B, a part of the interferometers 60A and 60B (particularly including a member serving as a heat source), for example, a light source, a detector, etc. Alternatively, it may be arranged outside the plate holder 12 and the like, and these may be optically connected to an optical system including a beam splitter inside the interferometer body via a relay system, for example, an optical fiber or FOP (fiber optic pickup). good.

  Further, as shown in FIGS. 2 and 1, an off-axis alignment system (hereinafter abbreviated as “alignment system”) ALG is fixed to the + Y side of the housing 38. As this alignment system, here, the target mark is irradiated with a broadband detection light beam that does not sensitize the resist on the plate P, and the target mark image formed on the light receiving surface by the reflected light from the target mark is not shown. An image processing method FIA (Field Image Alignment) that captures an image of an index (an index pattern on an index plate provided in the alignment system ALG) using an image sensor (CCD or the like) and outputs the imaged signals. ) System sensors are used. The alignment system ALG is not limited to the FIA system, and the target mark is irradiated with coherent detection light to detect scattered light or diffracted light generated from the target mark, or two diffractions generated from the target mark. Of course, it is possible to use alignment sensors that detect light (for example, diffracted light of the same order or diffracted light that is diffracted in the same direction) alone or in appropriate combination.

  In this case, all of the components constituting the alignment system ALG may be provided in the housing fixed to the housing 38, but some of them (particularly including a member serving as a heat source), such as a light source or an image sensor. Is disposed outside the housing, for example, in the following optical unit 18 (housing 28) or outside the plate holder 12, and optically connected to the optical components inside the housing via a relay system, for example, an optical fiber or FOP. You may make it connect. The output signal of the alignment system ALG is supplied to the aforementioned main controller 80 (see FIG. 5).

  Further, although not shown in FIG. 1, an irradiation area of trapezoidal illumination light via the projection optical system PL on the plate P, that is, an exposure area IA, as shown in FIG. AF detection systems 62 having a plurality of detection points AF1 to AF4 and AF5 to AF8, respectively, are provided before and after the scanning direction (Y-axis direction) (see FIG. 5). In the present embodiment, the AF detection system 62 is fixed to the bottom surface of the housing 38 as an example, and includes an air micrometer that detects the distance to the plate P surface at the detection points AF1 to AF4 and AF5 to AF8. As this air micrometer, for example, a type that detects a distance to a detection target (or displacement of the detection target) by back pressure of air is used. The measurement result of the AF detection system 62 is supplied to the main controller 80. In the main controller 80, a positional deviation amount (defocus amount) in the Z-axis direction at each detection point on the surface of the plate P with respect to the image plane of the pattern image by the known projection optical system PL and the image plane of the plate P surface. The amount of inclination with respect to is calculated.

  In the exposure apparatus 100 of the present embodiment, a reference member FM extends along the X-axis direction adjacent to the plate P as shown in FIG. 2 near the end portion in the −Y direction of the plate holder 12. Has been. The reference member FM is made of a light transmissive member, such as quartz glass, and the surface thereof is substantially flush with the surface of the plate P held by suction on the plate holder 12. The surface of the plate holder 12 other than the reference member FM is also substantially flush with the reference member FM. That is, the upper surface of the plate holder 12 includes the plate P, and the substantially entire surface is a full flat surface. Note that a part of the plate holder 12 that the first and second support members 24 and 26 are opposed to, for example, within the movement range of the pattern projection unit 14, not the entire surface of the plate holder 12, is the plate P and the reference member. It may be just flush with FM.

A light shielding film made of a metal such as chromium is formed on the surface of the reference member FM, and patterning is applied to the light shielding film to make aerial image measurement marks AIS _{1 to} AIS _n (n is an opening pattern). An integer of 2 or more, for example, 6 is formed at a predetermined pitch along the longitudinal direction of the reference member (coincides with the direction of the reflection surface of the first plane mirror 58Y), and between adjacent aerial image measurement marks. Baseline measurement marks FI _{1 to} FI _n-1 are respectively formed at the midpoints. The aerial image measurement marks AIS _{1 to} AIS _{n also} serve as aerial image measurement slits. The positional relationship in the Y-axis direction between each of the aerial image measurement marks AIS _{1 to} AIS _n and the marks FI _{1 to} FI _n-1 and the reflecting surface of the first plane mirror 58Y, and the aerial image measurement marks AIS _{1 to} AIS _n and The positional relationship between each of the marks FI _{1 to} FI _n−1 and the reflecting surface of the second plane mirror 58X in the X-axis direction is measured in advance and is known.

Inside the plate holder 12 below the reference member FM, a lens system provided corresponding to each of the aerial image measurement marks AIS _{1 to} AIS _n and a light receiving element such as a PMT (photomultiplier tube), The aerial image sensor 64 (not shown in FIG. 2, etc., see FIG. 5) is accommodated. The aerial image sensor 64 individually receives the light transmitted through the aerial image measurement marks AIS _{1 to} AIS _n of the reference member FM, that is, the aerial image measurement slits, by the light receiving elements through the lens systems. Here, a part of the aerial image sensor 64 (for example, including at least the light receiving element) may be disposed outside the plate holder 12. A method for using the aerial image sensor 64 will be described later.

As shown in FIG. 2, the plate P used in the present embodiment includes a rectangular frame-shaped region on the outer peripheral portion and a rectangular liquid crystal pixel portion PA surrounded by the rectangular frame-shaped region, In the rectangular frame-shaped region, k (k is an integer of 3 or more, for example, 9) alignment marks m _{1 to} m _k are formed.

  FIG. 5 is a block diagram showing the components related to the exposure control of the exposure apparatus 100. Among these, the main control device 80 mainly constitutes a control system. The main controller 80 includes a workstation or a microcomputer. The main controller 80 is provided with a mask pattern storage unit 66 in which reference marks (to be described later) displayed on the active mask 36 are stored.

  As can be seen from FIG. 5, the main controller 80 receives the measurement values of various measuring devices including the laser interferometer system 60, the linear encoder 68, and the displacement sensor 70, and the planar motor 23, X The axis linear linear motors 56A and 56B, the Y axis linear motor 48, the active mask 36, and the like are connected.

  In main controller 80, the distance is almost the same as the movement amount of pattern projection unit 14 in the X-axis direction on the basis of the measurement value of second interferometer 60 </ b> B of laser interferometer system 60 and the measurement value of linear encoder 68. The X-axis linear motors 56A and 56B are driven and controlled so that the following optical unit 18 is driven in the X-axis direction. Further, main controller 80 always drives Y-axis linear motor 48 based on the measurement value of displacement sensor 70. That is, in the present embodiment, the follow control of the follow optical unit 18 with respect to the pattern projection unit 14 is always performed by the main controller 80 in this manner. Description of the control of the unit 18 is omitted.

  Next, an operation flow in the exposure apparatus according to the present embodiment configured as described above will be described.

First, in the state where the plate P is not mounted on the plate holder 12, the relationship between the position of the active mask 36 and the position where the pattern image generated by the active mask 36 is projected is determined by the aerial image sensor 64. Use to find. That is, first, as shown in FIG. 6, the main controller 80 displays a pair of references displayed on the active mask 36 in a state where the pattern projection unit 14 is outside the plate placement area on the plate holder 12. Two adjacent aerial image measurement marks AIS _i on the reference member FM are displayed with images of marks (displayed at both ends in the longitudinal direction of the trapezoidal effective area (substantially coincident with the X-axis direction)). The pattern projection unit 14 is driven in the XY plane via the planar motor 23 so as to be formed in the vicinity of AIS _{i + 1} . Here, the distance between the pair of reference marks in the X-axis direction is determined so as to substantially coincide with the distance between two adjacent aerial image measurement marks on the reference member FM.

Next, the main controller 80 uses the aerial image sensor 64, and uses a pair of reference marks (aerial images) as the aerial image measurement by the slit scan method through the aerial image measurement marks AIS _i and AIS _{i + 1.} To detect. Note that the slit scanning aerial image measurement is disclosed in, for example, Japanese Patent Application Laid-Open No. 2002-14005 (corresponding US Patent Application Publication No. 2002/0041377) and the like, and is not described in detail. However, in the present embodiment, in the aerial image measurement, the main controller 80 drives the pattern projection unit 14 in the X-axis direction (or Y-axis direction) via the planar motor 23.

  Then, based on the measurement result of the aerial image of the pair of reference marks (the intensity signal of the aerial image (the horizontal axis is the measurement value of the first interferometer 60A or the second interferometer 60B of the laser interferometer system 60)). Then, the coordinate values (x1, y1) and (x2, y2) of the formation position of the aerial image of the pair of reference marks on the above-mentioned reference coordinate system are obtained, whereby the relative position between the active mask 36 and the plate holder 12 is obtained. (Positional relationship) is required.

  Prior to the above measurement, main controller 80 determines that the image forming position of at least one projection optical system PL of the pair of reference marks displayed on active mask 36 matches the surface of reference member FM. As described above, the wedge lens 37 is driven via a drive system (not shown) to adjust the image forming position of the projection optical system PL in the Z-axis direction. That is, the main controller 80 measures the aerial image of the reference mark by the slit scan method at each driving position while driving the wedge lens 37 by a predetermined amount, and outputs the intensity signal of the aerial image obtained at each driving position. For example, the driving position where the contrast is maximized is found, and the wedge lens 37 is adjusted at that position, thereby adjusting the imaging position in the Z-axis direction of the projection optical system PL.

  Next, main controller 80 determines, based on the coordinate values (x1, y1), (x2, y2), the θz rotation error of pattern projection unit 14 with respect to the coordinate axes on coordinate system (X, Y), that is, the plate. A yawing amount (θz rotation error) of the pattern projection unit 14 with respect to the holder 12 is calculated, and the pattern is transmitted via the planar motor 23 while monitoring the measurement value of the laser interferometer system 60 so that the yawing amount becomes zero. The projection unit 14 is rotationally driven in the θz direction. At this time, the pattern projection unit 14 rotates with the center of the pair of reference marks displayed on the active mask 36 as the rotation center.

Next, the distance between the baseline of the alignment system ALG, that is, the projection center of the pattern generated by the active mask by the projection optical system PL and the detection center of the alignment system ALG (matches the center of the index mark inside the alignment system ALG). (Position relationship) is obtained. That is, in the main controller 80, the pattern projection unit 14 and the tracking optical unit 18 are moved in the −Y direction by the baseline design value with respect to the plate holder 12 in the same manner as described above, and within the detection region of the alignment system ALG. positioning the mark FI _i of the center of the base line for measuring the mark AIS _i mark AIS i + _1, the measurement result of the alignment system ALG of this time, or relative to the detection center and the mark FI _i of alignment system ALG Capture location information. Then, the information on the relative position, the measured value of the laser interferometer system 60 at that time, and the formation positions of the aerial images of the pair of reference marks after the pattern projection unit 14 is rotated (the aerial images of the pair of reference marks). The base line of the alignment system ALG is calculated on the basis of the coordinate value of (the center of the formation position of is the projection center of the projection optical system PL). Here, the coordinate value of the formation position of the aerial image of each of the pair of reference marks after the rotation of the pattern projection unit 14 is the coordinate previously measured based on the rotation amount of the pattern projection unit 14 in the θz direction when adjusting the yawing amount. It can be obtained by correcting the values (x1, y1) and (x2, y2), respectively.

Next, main controller 80 conveys plate P onto plate holder 12 via a conveyance system (not shown), and uses alignment system ALG to detect at least two alignment marks among alignment marks m _{1 to} m _k . Detect location information. That is, main controller 80 sequentially positions alignment marks in the field of view of alignment system ALG in the same manner as the measurement of mark FI _i while monitoring the measurement values of laser interferometer system 60 according to the design values. Each time the alignment mark is detected using the alignment system ALG, the detection result (for example, the position of the alignment mark with respect to the detection center of the alignment system ALG) and the measurement value of the laser interferometer system 60 at that time are fetched, and the above-mentioned reference The position coordinates of each alignment mark on the coordinate system are calculated. By comparing the position coordinates of the alignment mark with the design value, the position of the plate P in the X-axis direction, the Y-axis direction, and yawing are obtained.

  In this case, the main controller 80 may detect the above-described alignment mark or an alternative pattern by a so-called template matching technique. For example, the main controller 80 aligns any one image of a pattern (referred to as “specific pattern” for convenience) in which a plurality of identical patterns exist in a predetermined positional relationship within the liquid crystal pixel portion PA on the plate P. A system ALG is used to capture the image data and store it in the memory as template data. Next, main controller 80 detects at least three of the plurality of specific patterns existing in a predetermined positional relationship inside liquid crystal pixel portion PA on plate P by a template matching method using the template data. Then, the position coordinates of the at least three specific patterns are calculated based on the detection result of each specific pattern and the measurement values of the laser interferometer system 60 at the time of detection. Then, the main control device 80, based on the calculated position coordinates of at least three specific patterns and the design value of each specific pattern, for example, statistical calculation (EGA) disclosed in Japanese Patent Application Laid-Open No. 61-44429 and the like. And calculating error parameters such as X offset, Y offset, rotation, X scaling, Y scaling, and orthogonality error of the partial area corresponding to the specific pattern inside the liquid crystal pixel portion PA. The arrangement coordinates of the specific pattern (and the corresponding partial area) may be obtained using the parameters.

  In this way, when the alignment of the plate P is completed, the main controller 80 starts exposure based on the alignment result.

  That is, the pattern projection unit 14 is moved relative to the plate P, and the position / posture of the pattern projection unit 14 is controlled in consideration of the alignment result, and in synchronization with the scanning of the pattern projection unit 14. A pattern is generated in the active mask, and the pattern is illuminated with illumination light from a light source. Thereby, the image of the pattern produced | generated via the projection optical system PL is transcribe | transferred on the plate P with which the photosensitive material (resist) was apply | coated.

  In the present embodiment, the center point C of the trapezoidal exposure area (pattern projection area) IA moves on the plate P along the trajectory (path) of one stroke as shown in FIG. The pattern generated by the active mask is sequentially transferred to the entire surface of the liquid crystal pixel portion PA on the plate P. As can be seen from FIG. 7, in the present embodiment, the inclination of one end of the trapezoidal exposure area IA in the non-scanning direction on the forward path from the one side of the Y-axis direction to the other side of the pattern projection unit 14 on the plate P. And an inclined region (the other end in the non-scanning direction of the trapezoidal exposure region IA on the return path of the pattern projection unit 14 from the other side in the Y-axis direction to the one side on the plate P) (The right triangle area) overlaps. As a result, in the liquid crystal pixel portion PA on the plate P, the width in the scanning direction of the projection region is constant regardless of the point in the X-axis direction, so that the entire surface of the liquid crystal pixel portion PA is uniform. The exposure is performed with a distribution of a sufficient accumulated energy amount (exposure dose amount).

  During the exposure described above, the main controller 80 detects the detection result of the AF detection system 62 (Z position information on the surface of the plate P at the detection points AF1 to AF8 (in this embodiment, between the surface of the plate P and the bottom surface of the projection optical system PL). Is always calculated at least in the exposure area IA with respect to the imaging plane of the projection optical system PL, with respect to the Z-axis direction of the surface of the plate P in the Z-axis direction, and the tilt amount. The plane motor 23 is driven based on the focus amount and the tilt amount, and the position of the pattern projection unit 14 in the Z-axis direction is adjusted, and the posture in the directions around the X-axis and Y-axis, that is, leveling adjustment is performed. Instead of or in conjunction with driving the pattern projection unit 14 in the Z-axis direction, driving the wedge lens described above allows defocusing. It may be correct.

  Further, during exposure or the like, the pattern projection unit 14 is driven by the planar motor 23, and at that time, a reaction force of the driving force acts on the armature unit 22 that is a mover of the planar motor 14. However, since the plate holder 12 provided with the armature unit 22 is supported by an air bearing (not shown) with respect to the upper surface of the support plate 10 through a predetermined clearance (for example, about several μm), By the action of the force, the pattern projection unit 14 moves in the direction opposite to the movement direction according to the law of conservation of momentum. As a result, the reaction force is completely absorbed and does not become a vibration factor. Therefore, the reaction force accompanying the driving of the pattern projection unit 14 hardly affects the exposure. In addition, since the movement of the pattern projection unit 14 is controlled based on the measurement value of the laser interferometer system 60 using the plane mirror 58 of the plate holder 12, for example, an image of the pattern generated by the active mask 36 during exposure is used. It is possible to align the plate P with high accuracy. Further, since the mass (2000 kg to 3000 kg) of the plate holder 12 is considerably larger than the mass of the pattern projection unit 14 (for example, several tens of kg), the moving amount of the plate holder 12 is very small (about several tens of mm at the maximum).

  As described above, according to the exposure apparatus 100 of the present embodiment, the pattern generated by the active mask 36 constituting the pattern projection unit 14 can be changed in synchronization with the scanning of the pattern projection unit 14. A desired pattern can be easily generated. Further, it is not necessary to provide a mask stage that is necessary when using a conventional mask that is an object pattern, and the cost and size of the exposure apparatus can be reduced. Further, in the exposure apparatus 100 of the present embodiment, the plate holder 12 on which the plate P is placed is fixed (actually moves slightly) and the pattern projection unit 14 moves, so the plate P is held and moved. There is no need to provide a stage to be operated and a large and heavy surface plate for supporting the stage. Therefore, compared with the conventional maskless type scanning projection exposure apparatus, it is possible to considerably reduce the footprint, reduce the size and weight, and reduce the cost. In addition, since the small and light pattern projection unit 14 moves, it is possible to suppress vibration caused by the reaction force of the driving force (thrust) during the movement, and thereby the pattern can be accurately placed on the plate P. It becomes possible to form.

  In the above embodiment, the pattern projection unit 14 is levitated and supported above the plate P (or the plate holder 12) by the air bearings provided on the first support member 24 and the second support member 26, respectively. Not limited to this, for example, an extension portion extending to the upper side of the housing 32 is provided on the end surface on the −Y side of the mounting member 42, and a magnet (permanent magnet or electromagnet) is provided in the extension portion and facing the magnet. A magnetic body may be provided on at least a part of the upper wall of the casing 32 (or the upper wall is formed of a magnetic material). In this way, the pattern projection unit 14 is balanced by the balance between the upward force due to the magnetic attraction force of the magnet and the upward force, which is the levitation force of the air bearing, and the weight of the pattern projection unit 14 (downward force). Can be levitated and supported above the plate P (or the plate holder 12). In this case, most of the weight of the pattern projection unit 14 may be supported by a magnetic attractive force.

  In the above embodiment, for example, instead of the first and second support members 24 and 26, a support member in which these support members 24 and 26 are integrated is provided. At least a part of the pattern projection unit 14 is provided on the support member in the direction of three degrees of freedom in the Z-axis direction and the tilt direction with respect to the XY plane. A configuration in which the micro drive is performed in the direction of at least one degree of freedom may be adopted. The micro drive mechanism can be configured to include a piezoelectric element or other actuator.

  In the embodiment described above, the first and second support members 24 and 26 both have air bearings and magnetic pole units on their bottom surfaces, but the first and second support members 24 and 26 have been described. At least one of these may not have an air bearing on its bottom surface. In this case, at least one of the supporting members can support at least a part of the weight of the pattern projection unit 14 by a magnetic force between the Z driving coil and the magnetic pole unit.

  In the above embodiment, the case where the exposure apparatus 100 includes one pattern projection unit 14 having a single projection optical system has been described. However, the present invention is not limited to this. For example, the exposure apparatus may include a pattern projection unit having a plurality of projection optical systems instead of the pattern projection unit 14 or may include a plurality of pattern projection units similar to the pattern projection unit 14 described above. good. In any case, since the plate P can be exposed using a plurality of projection optical systems at the same time, the throughput can be improved as compared with the above embodiment. In particular, when the exposure apparatus includes a plurality of pattern projection units, it is desirable to move each pattern projection unit with respect to the plate P along a path in which the plurality of pattern projection units do not contact each other. At this time, a plurality of pattern projection units may be held and moved together in a predetermined positional relationship. Note that the arrangement of the trapezoidal exposure areas by each projection optical system is as follows, regardless of whether a pattern projection unit having a plurality of projection optical systems is provided or a plurality of pattern projection units is provided. In addition, it is preferable to configure a plurality of projection optical systems or pattern projection units. That is, a plurality of trapezoidal exposure areas are arranged at predetermined intervals so as to be arranged after removing every other exposure area from a state where a plurality of trapezoidal exposure areas are alternately arranged in a reverse direction without gaps. Arrange the exposure areas in a row in the non-scanning direction (X-axis direction), or place every other trapezoidal exposure area shifted by a predetermined distance in the scanning direction instead of removing every other exposure area. By doing so, the plurality of trapezoidal exposure regions are arranged so as to be nested in two rows parallel to the non-scanning direction and separated by a predetermined distance in the scanning direction. In the former case, the entire surface of a predetermined area of the plate P can be exposed with a substantially uniform exposure amount by one reciprocating scan (including a stepping operation in the non-scanning direction having the same distance as the exposure area interval). In the latter case, the entire surface of a predetermined range of the plate P can be exposed with a substantially uniform exposure amount by a single scan from one side to the other side (or from the other side) in the scanning direction.

<< Second Embodiment >>
Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 8 shows a front view of the exposure apparatus 200 of the second embodiment, and FIG. 9 shows a plan view of the exposure apparatus 200. 10 shows a cross-sectional view taken along line AA in FIG. 9, and FIG. 11 shows a cross-sectional view taken along line BB in FIG.

  As shown in FIG. 8, the exposure apparatus 200 is installed on the floor surface F (or a base plate (not shown) installed on the floor surface F) of the clean room. The exposure apparatus 200 includes a plate holder 204 that is horizontally supported on a floor surface F via, for example, four anti-vibration units 202, and a horizontal plane (upper surface) along the upper surface of the plate P held on the plate holder 204. A pattern forming unit 206 movable in the XY plane in FIG. 8 and a drive system 208 for driving the pattern forming unit 206 are provided.

  The plurality of vibration isolation units 202 are adapted to insulate micro vibrations from the floor surface F toward the plate holder 204 at the micro G level.

  8 and 9, the plate holder 204 has a rectangular plate shape, and is provided with a rectangular plate placement area on which the plate P is placed at the center. As shown in FIG. 11, a large number of pin-shaped support portions 205 whose upper end surfaces are set at substantially the same height are provided on the plate mounting area on almost the entire surface, and are adjacent to each other in some places. One end of each of a plurality of vacuum exhaust passages 207 is connected to the inner bottom surface between the support portions 205. Each exhaust passage 207 is branched at its other end from an exhaust trunk (not shown), and the exhaust trunk is connected to a vacuum pump (not shown). In the present embodiment, the whole or at least the upper part of the plate holder 204 is formed using, for example, ceramic as a material, and the support portion 205 and the like are formed by performing an etching process on the upper surface of the ceramic portion. In the plate mounting region of the plate holder 204, a pin chuck for vacuum-sucking the plate P is formed in this way.

  On the −Y side of the plate mounting area on the upper surface of the plate holder 204, a reference member FM including the aerial image sensor 64 similar to that in the first embodiment is provided. The output of the aerial image sensor 64 is supplied to the main controller 280 (see FIG. 15).

  The pattern forming unit 206 is supported from below by a support member 210 as shown in FIG. More specifically, as shown in FIG. 11 and FIG. 9, the support member 210 is open at the top, the bottom wall is thinner than the peripheral wall (side wall), and the bottom wall It has a shape like a planar cylindrical member with a square opening formed in the center, and has a protruding portion 210a that protrudes inward from the inner wall surface of the peripheral wall at the bottom. As shown in FIG. 11, the support member 210 is provided with a plurality of air bearings 213 embedded in the bottom thereof, in this case, one in each of the four corners, in total, four air bearings 213. The pressurized air is jetted from the plate P toward the upper surface of the plate P (or the upper surface of the plate holder 204). The support member 210 and the pattern forming unit 206 are moved to the plate P by the static pressure (so-called clearance pressure) of pressurized air between the air bearing 213 (the support member 210) and the upper surface of the plate P (or the upper surface of the plate holder 204). The upper surface (or the upper surface of the plate holder 204) is supported via a predetermined clearance (for example, a clearance of about several μm).

  As shown in FIG. 11, the pattern forming unit 206 is placed on the above-described overhanging portion 210 a from above, and the first partial housing is set so that the lower end surface thereof is substantially flush with the bottom surface of the support member 210. 211a, and a substantially cylindrical second partial housing 211b fixed in a state where a part near the lower end is embedded in the upper part of the first partial housing 211a.

  A pattern forming portion 209 is accommodated in the internal space of the first partial housing 211a. The second partial housing 211b has a substantially stepped cylindrical outer shape, and an illumination system for illuminating the pattern forming unit 209 is accommodated in the internal space.

  FIG. 12 schematically shows an example of the configuration of the pattern forming optical system 212 inside the housing 211 (see FIG. 11) substantially constituted by the first partial housing 211a and the second partial housing 211b. Has been.

  The pattern forming optical system 212 includes a light source unit 214 including a light source, an optical integrator, a lens system, and the like, and 45 ° with respect to a horizontal plane below the light source unit 214 (more precisely, on the X axis in the XZ plane). And a collimator lens 218 disposed on the reflection light path of the illumination light emitted downward from the light source unit 214 by the total reflection mirror 216, and a collimator lens 218 disposed obliquely at an angle of 45 °) A DMD (digital micrometer) provided on the optical path of the illumination light that has passed through the collimator lens 218 with an angle of 45 ° to the horizontal plane (more precisely, 45 ° to the X axis in the XZ plane). Mirror device) 220 and the reflecting surface of all mirror elements of DMD 220 passed through collimator lens 218 when the angle of reflection is 45 ° with respect to the X axis in the XZ plane. A pattern forming unit 209 arranged in parallel to the XY plane is provided on the light path reflected by the DMD 220 of the illumination light.

  The pattern forming unit 209 is disposed below the optical element array 222 including a plate in which a plurality of optical elements are formed in a predetermined positional relationship on the XY plane, and facing each optical element of the optical element array 222. And a lens array 224 composed of a plurality of lenses.

The DMD 220 includes a plurality of mirror elements that can change the inclination angle of the reflecting surface, and each mirror element is connected to the main controller 280 (FIG. 15) via a DMD driving unit 226 (not shown in FIG. 12, refer to FIG. 15). In this way, it is possible to individually control the incidence or non-incidence of the illumination light to each optical element constituting the optical element array 222. In FIG. 13, among the arbitrary three optical elements FL _k−1 , FL _k , FL _{k + 1} on the optical element array 222 by driving a specific mirror element via the DMD driving unit 226, the optical A state in which illumination light is incident on the elements FL _k-1 and FL _{k + 1} and the illumination light is not incident on the optical element FL _k is schematically shown.

  As described above, in this embodiment, the DMD 220 functions as a spatial light modulator (SLM). Therefore, other reflective spatial light modulators such as a reflective mirror array may be used in place of the DMD 220 described above.

FIG. 14 shows a plan view of the optical element array 222. 14 also shows a spot image (hereinafter referred to as “spot”) SP formed on a predetermined surface (imaging surface) by each optical element FL _{i, j} of the optical element array 222. Has been. As shown in FIG. 14, the optical element array 222 includes m (m is, for example, 10) × n (n is, for example, 4) optical elements FL _{i, j} (i = 1 to m, j = 1 to n). ) Has a parallelogram-shaped plate 222a in a plan view provided in a predetermined arrangement.

On the plate 222a, m optical elements FL _{i, 1} (i = ₁ to m) arranged at a predetermined pitch p on a straight line L1 in a direction forming a predetermined angle θ with respect to the Y axis in the XY plane. The first row of optical element groups including m optical elements FL _{i, 2} (with a predetermined pitch p) on a straight line L2 extending in parallel to the straight line L1 at a predetermined distance d from the straight line L1 in the + X direction. a second row of optical element groups including i = 1 to m), m pieces arranged at a predetermined pitch p on a straight line L3 extending in parallel to the straight line L2 with a predetermined distance d from the straight line L2 in the + X direction. A third row of optical element groups including optical elements FL _{i, 3} (i = 1 to m) and a fourth straight line L4 extending in parallel to the straight line L3 at a predetermined distance d from the straight line L3 in the + X direction A fourth row of optical elements including m optical elements FL _{i, 4} (i = 1 to m) arranged at a predetermined pitch p in FIG. Is formed. The surface of the region (space region) where the optical element is not formed on the plate 222a is a light shielding region where a light shielding film made of a metal film such as chromium is formed.

In this case, a. The optical elements FL _{i, j} included in all groups are arranged at equal intervals when the center points thereof are translated in the Y-axis direction and arranged on the same straight line LL in the X-axis direction (at intervals Δd). Formed on the plate 222a. B. The optical elements FL _{i, 2} , FL _{i, 4} (i = 1 to m) constituting the optical element group in the second row and the optical element group in the fourth row are the optical element groups in the first row, respectively. Are shifted by a predetermined distance smaller than a predetermined pitch p in the Y-axis direction with respect to the respective optical elements FL _{i, 1} (i = _{1 to} m) constituting each of the optical elements constituting the optical element group in the third row. The elements FL _{i, 3} (i = 1 to m) are arranged in the Y-axis direction with the optical elements FL _{i, 1} (i = _{1 to} m) constituting the optical element group in the first column. This is because, when the illumination light beam (beam) is in a non-incident state as in the above-described optical element FL _k , one optical element is used so that the illumination light beam does not enter any optical element. In order to secure a light-shielding area having a predetermined area on the plate 222a, the entire area is accommodated. As a result, a light shielding area irradiated with the illumination light beam, such as a circular area with a shadow line in FIG. 14, can be secured on the plate 222a.

  A. And b. Is satisfied in accordance with the predetermined pitch p, the interval Δd, and the number m of optical elements in a row.

Further, as each optical element FL _{i, j} , a phase type diffractive optical element that forms a spot on a predetermined surface when illuminated with illumination light is used. In the present embodiment, each optical element FL _{i, j} forms an oval spot SP elongated in the X-axis direction as shown in FIG. 14 on a predetermined surface. The length of the spot SP in the X-axis direction is twice the distance Δd described above. That is, the spots SP formed by adjacent optical elements in the same row are arranged so as to overlap each other by a half in the X-axis direction.

Here, if the positional relationship between the center points of the optical elements is not different, each optical element is an element such as a Fresnel zone plate that forms a spot having the same diameter as the length of the spot SP on a predetermined surface. But of course. In any case, like the optical element array 222, each of them is on a plurality of straight lines (L1, L2, L3, L4, etc.) parallel to each other that form an angle θ (0 <θ <90 °) with respect to the Y axis. When a plurality of phase-type diffractive optical elements are arranged at a predetermined pitch p, the pitch p is set to a dimension corresponding to the shape of the spot formed on the predetermined surface (plate P surface) by each diffractive optical element. By moving the optical element array 222 in the Y-axis direction with respect to the plate P along the Y-axis direction, it is possible to expose a region of a predetermined area on the surface of the plate P with a spot without a gap. Become. In particular, in the present embodiment _, the centers of the optical elements FL _{i, j} are arranged at equal intervals Δd with respect to the Y-axis direction, and the length in the X-axis direction of the spot formed by each optical element FL _{i, j} is Δd / Therefore, it is possible to expose almost the entire area of the predetermined area with a uniform exposure amount distribution.

  The drive system 208 includes a first drive mechanism that drives the pattern forming unit 206 in the X-axis direction, and a second drive mechanism that drives the pattern forming unit 206 in the Y-axis direction integrally with the first drive mechanism. Yes.

  More specifically, as shown in FIG. 11, X-axis movers 228A and 228B project from the one side surface and the other side surface of the support member 210 in the Y-axis direction. These X-axis movers 228A and 228B have a substantially T-shaped YZ cross section as shown in FIGS. 9 and 11, and have a rectangular shape elongated in the X-axis direction when viewed from the + Z direction. It includes an armature unit having a plurality of armature coils arranged along the X-axis direction. These X-axis movers 228A and 228B are inserted into the internal spaces of the X-axis stators 230A and 230B, each having a U-shaped YZ section and extending in the X-axis direction when viewed from the + Z direction. These X-axis stators 230A and 230B are configured by a magnetic pole unit having a plurality of permanent magnets (adjacent permanent magnets having opposite polarities) arranged at predetermined intervals along the X-axis direction. Has been.

  As shown in FIG. 9, the X-axis stators 230A and 230B have one end and the other end in the longitudinal direction connected to Y-axis sliders 232A and 232B that are elongated in the Y-axis direction, respectively. As shown in FIG. 10, the Y-axis sliders 232A and 232B are formed of pentagonal members whose XZ cross-sections in which rectangular openings 233 and 234 are respectively formed are symmetrical with each other, and the respective openings 233 and 234 are formed. A plurality of armature coils (not shown) are arranged at predetermined intervals along the Y-axis direction on the inner wall surface.

  As shown in FIG. 10, Y-axis guides 236A and 236B having a rectangular XZ section are inserted into the openings 233 and 234 of the Y-axis sliders 232A and 232B, respectively. One end and the other end of one Y-axis guide 236A in the longitudinal direction are supported so as to be parallel to the XY plane by frames 238A and 238B implanted on the floor surface F, as shown in FIG. . Also, one end and the other end of the other Y-axis guide 236B in the longitudinal direction are parallel to the XY plane by the frames 238C and 238D planted on the floor surface F, and the same height as the Y-axis guide 236A. (See FIG. 9). Y-axis guides 236A and 236B each have a magnet group including a plurality of N-pole permanent magnets and S-pole permanent magnets arranged alternately at predetermined intervals along the longitudinal direction.

  In this embodiment, as can be seen from FIG. 9, the X-axis stators 230A and 230B and the Y-axis sliders 232A and 232B constitute a rectangular Y-axis moving body 240.

  As is apparent from the above description, the X-axis stators 230A and 230B and the corresponding X-axis movers 228A and 228B drive the pattern forming unit 206 supported by the support member 210 in the X-axis direction. A pair of X-axis linear motors LMX1 and LMX2 composed of magnet type linear motors are respectively configured (see FIG. 11). The pattern forming unit 206 can be driven in the θz direction (rotating direction around the Z axis) by making the driving force (thrust) generated by each of the X-axis linear motors LMX1 and LMX2 different.

  In addition, the Y-axis guides 236A and 236B and the corresponding Y-axis sliders 232A and 232B move the pattern forming unit 206 that is integrated with the Y-axis moving body 240 and supported by the support member 210 in the Y-axis direction. A pair of Y-axis linear motors LMY1 and LMY2 each including the linear motor are configured (see FIG. 10).

  As described above, in this embodiment, at least a part of the first drive mechanism that drives the pattern forming unit 206 in the X-axis direction is configured by the pair of X-axis linear motors LMX1 and LMX2, and the pair of Y-axis linear motors LMY1 and LMY1. At least a part of the second drive mechanism that drives the pattern forming unit 206 in the Y-axis direction integrally with the first drive mechanism is configured by LMY2.

  Between the projecting portion 210a (see FIG. 11) of the support member 210 and the first partial housing 211a, the first partial housing 211a is slightly positioned in the Z-axis direction at three positions that are not on the same straight line in the XY plane. Three actuators 242a to 242c to be driven (not shown in FIG. 11, refer to FIG. 15) are provided. As each actuator, for example, a piezo element or a voice coil motor can be used.

On the −Y side of the reference member FM on the upper surface of the plate holder 204, as shown in FIG. 9, three Y-axis laser interferometers 244Y ₁ , 244Y ₂ , and 244Y ₃ are shorter than the length of one side of the support member 210. They are arranged at a predetermined interval. The measurement beams from these Y-axis laser interferometers 244Y ₁ , 244Y ₂ , and 244Y ₃ are representatively shown by measuring the measurement beam MY ₂ from the Y-axis laser interferometer 244Y ₂ in FIG. The reflection surface of the Y-axis movable mirror 246 formed of a plane mirror extending in the X-axis direction provided in the vicinity of the lower end portion of the −Y side end surface of the support member 210 is irradiated. Each of the Y-axis laser interferometers 244Y ₁ , 244Y ₂ , and 244Y ₃ is a multi-axis interferometer having at least two measurement axes, and includes not only the position of the support member 210 (pattern forming unit 206) in the Y-axis direction. , Θz rotation is also measured.

In this case, the length measurement beam MY ₂ is irradiated to a height position substantially coinciding with the surface on which the optical element array 222 is disposed. The length measuring beams from the other Y-axis laser interferometers 244Y ₁ and 244Y ₃ are also irradiated at the same height position. In other words, any of the Y-axis laser interferometers 244Y ₁ , 244Y ₂ , and 244Y ₃ can measure the position of the support member 210 (pattern forming unit 206) in the Y-axis direction without so-called Abbe error.

Further, in the vicinity of the + X side end of the upper surface of the plate holder 204, five X-axis laser interferometers 244X ₁ , 244X ₂ , 244X ₃ , 244X ₄ , and 244X ₅ are attached to the support member 210 as shown in FIG. They are arranged at a predetermined interval shorter than the length of one side. The measurement beams from these X-axis laser interferometers 244X ₁ , 244X ₂ , 244X ₃ , 244X ₄ , and 244X ₅ pass through an in-plane optical path having the same height as the above-mentioned measurement beam MY ₂ to support members. The reflection surface of an X-axis moving mirror (not shown) composed of a plane mirror extending in the Y-axis direction provided in the vicinity of the lower end of the + X side end surface of 210 is irradiated. Therefore, any of the X-axis laser interferometers 244X ₁ , 244X ₂ , 244X ₃ , 244X ₄ and 244X ₅ can measure the position of the support member 210 (pattern forming unit 206) in the X-axis direction without so-called Abbe error. ing. Instead of providing the X-axis and Y-axis moving mirrors on the support member 210, for example, the end surface (side surface) of the support member 210 may be mirror-finished and used as a reflection surface.

The measured values of the three Y-axis laser interferometers 244Y ₁ , 244Y ₂ , 244Y ₃ and the five X-axis laser interferometers 244X ₁ , 244X ₂ , 244X ₃ , 244X ₄ , 244X ₅ are supplied to the main controller 280. (See FIG. 15).

  As can be seen from the above description, in the second embodiment, before the length measurement beam from one Y-axis laser interferometer does not hit the Y-axis moving mirror 246, the one from the one Y-axis laser interferometer. There is always a time for the length measuring beam from the adjacent Y axis laser interferometer to hit the Y axis moving mirror 246 at the same time that the length measuring beam hits the Y axis moving mirror 246. The same applies to the five X-axis laser interferometers. For this reason, the main controller 280 measures the Y-axis laser interferometer that has been used for control until the measurement beam from the two Y-axis laser interferometers hits the Y-axis moving mirror 246. A so-called connection preset is executed by using the value to preset the measurement value of the adjacent Y-axis laser interferometer used for the next control. Similarly, main controller 280 performs a tethering preset for the X-axis laser interferometer.

  Although not shown in FIGS. 8 to 11 and the like, an AF detection system 62 similar to the above is provided around a region on the predetermined surface where the spot group is formed by the pattern forming unit 206. In addition, an alignment system ALG similar to that described above is provided in a part of either the pattern forming unit 206 or the support member 210 (see FIG. 15).

  FIG. 15 is a block diagram showing constituent parts related to exposure control of the exposure apparatus 200 according to the second embodiment. Among these, the main control device 280 mainly constitutes a control system. The main controller 280 includes a workstation or a microcomputer. The main controller 80 is provided with a mask pattern storage unit 66 similar to that of the first embodiment.

  According to the exposure apparatus of the present embodiment configured as described above, the main controller 280 performs the same procedure as in the first embodiment described above, and the position of the plate P in the X-axis direction, the Y-axis direction, and The alignment of the plate P to be yawed is performed. When the alignment of the plate P is completed, main controller 280 starts exposure based on the alignment result.

That is, the main controller 280 moves the pattern forming unit 206 relative to the plate P, and controls the position / posture of the pattern forming unit 206 in consideration of the above alignment result. The mirror elements of the DMD 220 are individually driven via the DMD driving unit 226 in synchronization with the scanning of the above, so that the incident or non-incidence of the illumination light to each optical element FL _{i, j} constituting the optical element array 222 is individually Control. Thus, the spot SP is formed on the plate P only by the optical element on which the illumination light is incident, and the resist on the plate P is exposed by the spot SP to form a pattern. The pattern formed in this way is sequentially changed by the main controller 280 in synchronization with the scanning of the pattern forming unit 206 based on the contents stored in the mask pattern storage unit 66.

  In the present embodiment, the central point of the optical element array 222 (plate 222a) inside the pattern forming unit 206 is located with respect to the plate P along the locus (path) of one stroke writing as in the first embodiment. By relative movement, patterns are sequentially formed on the entire surface of the liquid crystal pixel portion on the plate P. In this case, the pattern forming unit 206 has an inclined region (right triangle region) at one end in the non-scanning direction of the parallelogram plate 222a in the forward path from one side to the other side in the Y-axis direction, and the pattern forming unit 204 On the XY plane where the optical element array 222 is disposed, the inclined region (right triangle region) at the other end in the non-scanning direction of the parallelogram plate 222a on the return path from the other side to the one side in the Y-axis direction. The movement of the pattern forming unit 206 along the trajectory (path) of the one-stroke writing and the incidence or non-incidence of illumination light to each optical element constituting the optical element array 222 synchronized with this Control is performed (see FIG. 16). As a result, since the arrangement of the spots formed on the surface of the plate P, that is, the shape and arrangement of the pattern can be changed, the plate P in which a desired pattern is formed in the entire area of the liquid crystal pixel portion on the plate P. Exposure to is realized. In this case, the exposure is performed on the entire surface of the liquid crystal pixel portion on the plate P with the distribution of the uniform integrated energy amount (exposure dose amount) in the region to be exposed.

  During the exposure described above, the main controller 280 constantly calculates a displacement amount (defocus amount) and an inclination amount with respect to the Z-axis direction of the surface of the plate P with respect to the formation surface of the spot SP based on the detection result of the AF detection system 62. Then, the actuators 242a to 242c are driven based on the defocus amount and the tilt amount, and the position of the pattern forming unit 206 in the Z-axis direction is adjusted, and the posture in the X-axis and Y-axis directions is adjusted, that is, leveling is performed. Adjustments are being made.

  As described above, according to the exposure apparatus 200 of the second embodiment, the DMD 220 constituting a part of the pattern forming unit 206 is controlled via the DMD driving unit 226 in synchronization with the scanning of the pattern forming unit 206. By doing so, the arrangement of the spots formed on the surface of the plate P, that is, the shape and arrangement of the pattern can be changed, so that a desired pattern can be easily formed on the plate P. Further, it is not necessary to provide a mask stage that is necessary when using a conventional mask that is an object pattern. Further, in the exposure apparatus 200 of the present embodiment, the plate holder 204 on which the plate P is placed is fixed and the pattern forming unit 206 moves, so that a large and heavy surface plate that supports a stage or the like that holds the substrate. Is no longer necessary. Therefore, compared with the conventional maskless type scanning projection exposure apparatus, it is possible to considerably reduce the footprint, reduce the size and weight, and reduce the cost.

  Further, the reaction force of the driving force when driving the pattern forming unit 206 in the X-axis direction is transmitted to the Y-axis guides 236A and 236B via the Y-axis moving body 240, and the pattern forming unit 206 is driven in the Y-axis direction. The reaction force of the driving force at this time acts on the Y-axis guides 236A and 236B, but the reaction force transmitted to or acting on the Y-axis guides 236A and 236B is applied to the floor surface F via the frames 238A to 238D. To escape. Further, vibration from the floor surface F is prevented from being transmitted to the plate holder 204 by the vibration isolation unit 202. Therefore, the reaction force during driving of the pattern forming unit 206 hardly causes the vibration of the plate holder 204, and the pattern can be formed on the plate P with high accuracy by suppressing this vibration.

  In the second embodiment, the case where the optical element array 222 includes the first to n-th columns (n is, for example, 4) of optical element groups has been described. The array may include at least two rows, for example, only the first row optical element group and the second row optical element group in the second embodiment.

  In the second embodiment, the case where the pattern forming unit 206 including the optical element array 222 is moved with respect to the plate P has been described. However, the present invention is not limited thereto, and is disclosed in, for example, Japanese Patent Application Laid-Open No. 2004-327660. The present invention can also be used in a maskless type scanning projection exposure apparatus having such a substrate stage. Even in such a case, it is not necessary to provide a mask stage, and a desired pattern can be easily formed on the substrate. In this case, only the substrate stage may be movable, or the pattern forming unit 206 may be movable, and the substrate stage and the pattern forming unit 206 may be relatively scanned in the scanning direction during exposure.

  In the first embodiment, the exposure apparatus includes a pattern projection unit including a transmissive liquid crystal display element (electronic mask 36) that is a non-light-emitting image display element installed in an optical path of illumination light from a light source. As described above, in the second embodiment, the optical element array 222 and the DMD 220 that controls the incidence and non-incidence of the illumination light to each optical element that is arranged on the optical path of the illumination light from the light source and constitutes the optical element array 222. However, the present invention is of course not limited to this.

  For example, in the first embodiment, the following non-light-emitting image display element may be used instead of the transmissive liquid crystal display element. Here, the non-light-emitting image display element is also called a spatial light modulator (SLM), and is an element that spatially modulates the amplitude, phase, or polarization state of light. Among these spatial light modulators, examples of the transmissive spatial light modulator include an electrochromic display (ECD) in addition to the above-described transmissive liquid crystal display element. As the reflective spatial light modulator, the above-described DMD (Deformable Micro-mirror Device or Digital Micro-mirror Device), reflective mirror array, reflective liquid crystal display element, electrophoretic display (EPD: ElectroPhoretic Display), electronic Examples include paper (or electronic ink), and a light diffraction type light valve.

  In the first embodiment, the pattern projection unit may include a self-luminous image display element instead of the light source and the non-luminous image display element installed in the optical path of the illumination light from the light source. Similarly, in the second embodiment, a pattern forming unit including a self-luminous image display element and a lens array may be used instead of the pattern forming unit 204. Here, as a self-luminous image display element, for example, a cathode ray tube (CRT), an inorganic EL display, an organic EL display (OLED: Organic Light Emitting Diode), an LED display, an LD display, a field emission display (FED: Field Emission). Display), plasma display (PDP: Plasma Display Panel), and the like. In addition, as a self-luminous image display element, a solid light source chip having a plurality of light emitting points, a solid light source chip array in which a plurality of chips are arranged in an array, or a type in which a plurality of light emitting points are formed on one substrate A pattern may be formed by using an object or the like and electrically controlling the solid-state light source chip. The solid light source element may be inorganic or organic.

<< Third Embodiment >>
Next, a third embodiment of the present invention will be described with reference to FIG. The exposure apparatus 300 of the third embodiment is supported by a base plate BS installed horizontally (parallel to the XY plane) on the floor surface F of the clean room, and a plurality of vibration isolation units 302 on the base plate BS. A support platen 304, a plate support holder 308 which is supported substantially horizontally by a holder support mechanism 306 above the support platen 304 and holds a glass plate (hereinafter abbreviated as “plate”) P by vacuum suction or the like, A plurality of support members 310 disposed below the plate P held by the plate support holder 308 and provided on the bottom surface of the support surface plate 304 with a predetermined clearance (for example, about several μm). The supported pattern forming unit 312 and the pattern forming unit 312 are driven in the XY plane along the upper surface of the plate P. That includes a drive system or the like. In practice, the plate P is held so that the surface thereof is substantially flush with the plate support holder 308.

  The holder support mechanism 306 includes a plurality of struts 305 (only four struts 305 are shown in FIG. 17) respectively installed in different positions of the base plate BS and extending in the Z-axis direction. A support mechanism main body 309 is provided which is supported and has a plate support holder 308 integrally provided on the lower surface thereof. Although not shown, each of the plurality of support columns 305 is provided with a vibration isolation unit so that vibration from the floor or the like is not transmitted to the holder support mechanism 306.

  The pattern forming unit 312 is integrally connected to a first housing 316 that houses therein a light source unit 314 similar to the light source unit 214 described above and a lens (not shown), and the + Y side of the first housing 316. The second casing 318 and the second casing 318 are provided in an angle of 45 ° with respect to the horizontal plane (more precisely, 45 ° with respect to the Y axis in the YZ plane). A DMD 320 similar to the DMD 220 described above, a lens (not shown), and the like, a third housing 322 that is fixed to the upper portion of the second housing 318, and that has an upper surface and a lower surface that are open, and is disposed inside the third housing 322. , And a pattern forming unit 324 having the same configuration as the above-described pattern forming unit 209 held substantially horizontally above the DMD 320. In this case, the above-described pattern including the light source unit 314, the DMD 320, the pattern forming unit 324, the lens, and the like in the housing substantially constituted by the first housing 316, the second housing 318, and the third housing 322. A pattern forming optical system similar to the forming optical system 212 is configured.

  The plurality of support members 310 provided on the bottom surface of the housing of the pattern forming unit 312 have a plurality of gas static pressure bearings such as air bearings and a magnetic pole unit including a plurality of permanent magnets on the bottom surface.

  Inside the supporting surface plate 304, an armature unit including a coil array composed of a large number of coils arranged at predetermined intervals in the XY two-dimensional direction is provided. The coil array constituting the armature unit includes a Z driving coil in addition to the X driving coil and the Y driving coil. The armature unit, along with the magnetic pole unit, drives the pattern forming unit 14 freely in the X-axis direction and the Y-axis direction, as well as the Z-axis direction, the θx direction (rotational direction around the X axis), and the θy direction (around the X axis). An actuator that micro-drives in the rotation direction) and the θz direction (rotation direction around the Z axis), for example, a magnetic levitation type planar motor similar to the planar motor 23 described above is configured. The drive system described above is configured including this planar motor.

  The support mechanism main body 309 has an isosceles trapezoidal shape when viewed from the front, and is a flat for adjusting the flatness of the plate support holder 308 and the plate P at a position between the upper and lower bases of the trapezoid. A degree adjusting mechanism 313 is provided. As a result of adjusting the flatness of the plate P by the flatness adjusting mechanism 313, the clearance between the upper end surface of the pattern forming unit 312 and the plate P is set to a desired value.

  Near the end of the lower end surface of the support mechanism main body 309, interferometer moving mirrors 326 </ b> A and 326 </ b> B composed of elongated flat mirrors are fixed. Laser interferometers 328A, 328B and the like for irradiating these movable mirrors 326A, 326B with measurement beams are provided on the outer surface of the third housing 322 of the pattern forming unit 312. A laser interferometer system similar to the laser interferometer system 60 described above is configured including the laser interferometers 328A, 328B, etc., and position information in the XY plane of the pattern forming unit 312 is measured by the laser interferometer system.

  Although not shown, the exposure apparatus 300 is provided with an alignment system, an AF detection system, an aerial image sensor, a DMD driving unit, a main controller, and the like, as in the second embodiment.

  According to the exposure apparatus 300 of the third embodiment configured as described above, the plate P is exposed in the same manner as in the second embodiment described above, and the same effect can be obtained. However, in the exposure apparatus 300 of the third embodiment, the pattern forming unit 312 is driven by a planar motor.

  In the third embodiment, in order to cancel the reaction force generated when the pattern forming unit 312 moves, for example, the support surface plate 304 is placed on a fixed surface plate (base) supported by a plurality of vibration isolation units 302. The support surface plate 304 may be arranged in a non-contact manner and can be finely moved by the reaction force.

  Furthermore, in the third embodiment, the pattern projection unit of the first embodiment described above may be used instead of the pattern forming unit 312. In such a case, the same effect as described above can be obtained.

  In the above embodiments, one pattern (liquid crystal display) is formed on the plate P. However, the present invention is not limited to this. For example, a plurality of patterns of the same size may be formed on the same plate. Alternatively, a plurality of patterns having different sizes may be formed on the same plate. In particular, in the latter case, the plate utilization efficiency can be maximized regardless of the plate size.

<Device manufacturing method>
Next, an embodiment of a device manufacturing method using the exposure apparatus of each of the above embodiments in a lithography process will be described. FIG. 18 is a flowchart showing a method for manufacturing a liquid crystal display element as a micro device.

  First, in step 402 (pattern formation process) in FIG. 18, a substrate such as a glass plate coated with a resist is exposed using the exposure apparatus of each of the above embodiments, and a circuit pattern is formed on the substrate. An optical lithography process is performed. By this photolithography process, a predetermined pattern including a large number of electrodes and the like is formed on the substrate. Thereafter, the exposed substrate is subjected to various processes such as a development process, an etching process, and a resist stripping process, whereby a predetermined pattern is formed on the substrate such as a glass plate.

  In the next step 404 (color filter forming process), a large number of sets of three dots corresponding to R (Red), G (Green), and B (Blue) are arranged in a matrix or R, G, and B A set of three stripe filters forms a color filter arranged in a plurality of horizontal scanning line directions.

  In the next step 406 (cell assembly process), a liquid crystal is formed using the substrate having the predetermined pattern obtained in the pattern formation process (step 402), the color filter obtained in the color filter formation process (step 404), and the like. Assemble the panel (liquid crystal cell). In this step 406 (cell assembly process), for example, liquid crystal is injected between the substrate having a predetermined pattern obtained in the pattern formation process and the color filter obtained in the color filter formation process, and a liquid crystal panel ( Liquid crystal cell).

  Thereafter, in step 408 (module assembly process), components such as an electric circuit and a backlight for performing display operation of the assembled liquid crystal panel (liquid crystal cell) are attached to complete the liquid crystal display element.

  Therefore, in the pattern forming process of the microdevice manufacturing method, a substrate such as a glass plate is exposed using the exposure apparatus of each of the above embodiments, and the pattern generated by the pattern generation unit is accurately formed on the substrate. The pattern can be accurately formed on the substrate by transfer or by the pattern forming unit.

  As described above, the exposure apparatus of the present invention is suitable for exposure of large substrates such as glass plates. The optical element array and multi-spot beam generator of the present invention are suitable for use in a pattern forming portion of an exposure apparatus used for exposure of such a large substrate. The device manufacturing method of the present invention is suitable for manufacturing micro devices such as liquid crystal display elements.

It is a figure which shows schematically the structure of the exposure apparatus of 1st Embodiment. It is a perspective view which shows the plate holder and pattern projection unit of FIG. It is a figure which shows the structure of the optical system inside the housing | casing of a pattern projection unit. It is a figure which shows the detection point of AF detection system with the image field IF of a projection optical system, and the exposure area | region set in the inside. It is a block diagram which shows each structure part relevant to the exposure control of the exposure apparatus of 1st Embodiment. FIG. 5 is a diagram for explaining an operation for obtaining a relative position (positional relationship) between an active mask and a plate holder, and is a perspective view showing a state in which an exposure apparatus pattern projection unit is outside a plate placement region on the plate holder. FIG. FIG. 6 is a diagram schematically showing a trajectory in which a center point C of a trapezoidal exposure area (pattern projection area) moves on a plate P; It is a front view which shows the exposure apparatus of 2nd Embodiment. It is a top view which shows the exposure apparatus of FIG. FIG. 10 is a sectional view taken along line AA in FIG. 9. FIG. 10 is a sectional view taken along line B-B in FIG. 9. It is a figure which shows typically an example of a structure of the pattern formation optical system inside the housing substantially comprised by the 1st partial housing 211a and the 2nd partial housing 211b. By driving a specific mirror element, illumination light is incident on two of the three optical elements on the optical element array 222, and no illumination light is incident on the remaining optical elements. It is a figure which shows the state set up like this typically. 3 is a plan view showing an optical element array 222. FIG. It is a block diagram which shows each structure part relevant to the exposure control of the exposure apparatus of 2nd Embodiment. An inclined region (right triangle region) at one end of the parallelogram plate in the non-scanning direction during movement along the forward path of the pattern forming unit during exposure and a parallelogram during movement along the return path It is a figure which shows visually a mode that the inclination part area | region (right-angled triangle area | region) of the other end part of a plate in the non-scanning direction overlaps on XY plane in which an optical element array is arrange | positioned. It is a figure which shows schematically the structure of the exposure apparatus of 3rd Embodiment. It is a flowchart for demonstrating embodiment of a device manufacturing method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Support plate, 12 ... Plate holder, 14 ... Pattern projection unit, 22 ... Armature unit, 23 ... Planar motor, 24 ... 1st support member, 26 ... 2nd support member, 30 ... Light source, 34 ... Frame, 36 ... Active mask, 48 ... Y-axis linear motor, 56A, 56B ... X-axis linear motor, 60 ... Laser interferometer system, 100 ... Exposure apparatus, 200 ... Exposure apparatus, 204 ... Plate holder, 206 ... Pattern forming unit, 212 ... Pattern forming optical system, 220 ... DMD, 222 ... Optical element array, 222a ... Plate, 242a to 242b ... Actuator, P ... Plate, PL ... Projection optical system, LMX1, LMX2 ... X-axis linear motor, LMY1, LMY2 ... Y-axis linear motor, FL _ij ... Optical element.

Claims (33)

An exposure apparatus that exposes a substrate to form a predetermined pattern on the substrate,
A substrate holding member for holding the substrate substantially flat;
A pattern forming portion for forming a pattern on the substrate;
A support that is provided in the pattern forming portion so as to face the substrate held by the substrate holding member, and supports at least a part of the pattern forming portion with respect to the surface of the substrate via a predetermined clearance in the direction of gravity. With members;
A drive system for driving the pattern forming portion, which is supported by the support member with respect to the substrate through a predetermined clearance in the direction of gravity, along the surface of the substrate;
An exposure apparatus provided.   2. The pattern forming unit supported by the support member includes at least a patterning member that is illuminated with illumination light to generate a pattern, and a holding member that holds the patterning member. The exposure apparatus described in 1.   The exposure apparatus according to claim 2, wherein at least a part of the pattern forming unit supported by the support member further includes a projection optical member that forms and projects the generated pattern on the substrate.   4. The exposure apparatus according to claim 3, wherein the projection optical member includes a catadioptric projection optical system including a refractive optical element and a reflective optical element.   The drive system includes a mover provided on at least a part of the pattern forming part and a stator provided on the substrate holding member, and at least a part of the pattern forming part is parallel to the substrate surface. The exposure apparatus according to claim 1, further comprising an actuator that drives in at least two degrees of freedom including a two-dimensional in-plane direction.   The exposure apparatus according to claim 1, further comprising a position measurement device that measures position information of at least a part of the pattern forming unit.   The drive system includes a first linear motor that drives at least a part of the pattern forming unit in a first axis direction, and at least a part of the first linear motor and the pattern forming unit intersects the first axis direction. The exposure apparatus according to claim 1, further comprising a second linear motor that drives in the second axial direction.   At least a part of the pattern forming portion on the support member is a direction of at least one degree of freedom among a third axis direction orthogonal to the first axis direction and the second axis direction, and a direction of inclination of three degrees of freedom. The exposure apparatus according to claim 7, further comprising a minute driving mechanism that minutely drives the lens. A position measuring device for measuring position information of at least a part of the pattern forming unit;
The position measuring device irradiates the pattern forming unit with a length measuring beam through one side in the gravitational direction of the stator of the first linear motor, and the second axial direction of at least a part of the pattern forming unit The exposure apparatus according to claim 7, further comprising an interferometer that measures a position related to the position.   The position measuring device irradiates the pattern forming unit with a length measuring beam through one side in the gravity direction of the stator of the second linear motor, and the first axial direction of at least a part of the pattern forming unit The exposure apparatus according to claim 9, further comprising an interferometer that measures a position relating to the exposure apparatus.   The exposure apparatus according to any one of claims 1 to 10, further comprising a load reduction mechanism that reduces a load in a gravity direction applied to the substrate from at least a part of the pattern forming portion supported by the support member.   The exposure apparatus according to claim 1, wherein the pattern forming unit includes a first portion supported by the support member and another second portion.   The exposure apparatus according to claim 12, wherein the second part includes an illumination optical member of a patterning member that is illuminated with illumination light and generates a pattern in the pattern generation unit.   The drive system includes a first drive system that drives the first part along the surface of the substrate, and a second drive system that drives the second part so as to follow the first part. The exposure apparatus according to claim 12 or 13, characterized in that:   The exposure apparatus according to claim 1, wherein the support member supports at least a part of the pattern forming portion hydrodynamically or electromagnetically.   The exposure apparatus according to any one of claims 1 to 15, further comprising another support member that movably supports the substrate holding member in a plane parallel to the surface of the substrate.   The substrate holding member has a first region on which the substrate is placed and a second region around the first region, and a surface of the second region is placed on the first region. The exposure apparatus according to claim 1, wherein the exposure apparatus is set to a height that is substantially flush with a surface of the substrate.   A plurality of optical elements arranged at a predetermined pitch on a first straight line in a third axis direction that forms a predetermined angle with respect to the second axis in a two-dimensional plane including the first axis and a second axis orthogonal thereto. A first row of optical element groups including elements, and a plurality of optical elements arranged at the predetermined pitch on a second straight line spaced from the first straight line by a predetermined distance in the first axis direction. The optical element group in the two rows is a phase type diffractive optical element that includes at least a formed plate, and forms a spot on a predetermined surface when each of the optical elements is illuminated with illumination light. A featured optical element array.   On the plate, a plurality of optical elements arranged at the predetermined pitch on a third straight line spaced from the second straight line in the first axial direction on the opposite side of the first straight line by the predetermined distance. 19. The optical element array according to claim 18, further comprising a third row of optical element groups including elements.   The optical elements included in all the groups are arranged on the plate at equal intervals when their center points are translated in the second axis direction and arranged on the same straight line in the first axis direction. The optical element array according to claim 18 or 19, wherein the optical element array is formed as follows.   Each optical element constituting the optical element group in the second row is shifted by a predetermined distance smaller than the predetermined pitch in the second axis direction with respect to each optical element constituting the optical element group in the first row. 21. The optical element array according to claim 20, wherein:   The optical element array according to claim 20 or 21, wherein each of the optical elements forms a spot having a predetermined shape elongated in the first axis direction on the predetermined surface.   When arranged on the same straight line in the first axial direction, spots formed on the predetermined surface by optical elements adjacent to each other on the straight line overlap at least partially with respect to the first axial direction. The optical element array according to claim 22, wherein the optical element array is arranged as described above.   24. The optical element array according to claim 22 or 23, wherein a length of each spot in the first axial direction is twice the equal interval.   The optical element array according to any one of claims 18 to 24, wherein a surface of the plate on which the optical element is not formed is a light shielding region.   The optical element according to any one of claims 18 to 25, wherein a region having a predetermined area in which an entire optical element is accommodated is provided between the optical element groups in the adjacent rows. Array. A multi-spot beam generator for forming a plurality of spot beams on a predetermined surface,
An optical element array according to any one of claims 18 to 26;
A multi-spot beam generator comprising: a spatial light modulator that realizes incidence and non-incidence of individual illumination light to each optical element constituting the optical element array.   28. The multi-spot beam generator of claim 27, wherein the spatial light modulator includes a digital micromirror device. An exposure apparatus that exposes a substrate to form a predetermined pattern on the substrate,
A substrate holding member for holding the substrate substantially flat;
29. A pattern forming unit including the multi-spot beam generator according to claim 27 or 28, wherein the substrate is exposed by a plurality of spot beams by the multi-spot beam generator to form a pattern;
An exposure apparatus comprising: a drive system that drives at least one of the substrate holding member and the pattern forming unit and relatively scans in the second axis direction.   30. The exposure apparatus according to claim 1, wherein the substrate is a rectangular large substrate having a length of 500 mm or more on at least one side.   The exposure apparatus according to any one of Claims 1 to 17, 29, and 30, wherein the substrate is a transparent substrate for display.   A device manufacturing method including a lithography step of exposing a substrate using the exposure apparatus according to any one of claims 1 to 17 and 29 to 31. The device manufacturing method according to claim 32, wherein in the lithography process, a liquid crystal display is formed on the substrate by the exposure apparatus.

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