JP2002141270A - Exposing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exposing system for accurately detecting positional information for an object or a moving body using an optical system by preventing the distortions of an optical element provided, in the optical path of an light beam. SOLUTION: The optical element LZ put in the optical path of light beam is supported with three points, in contact with one face of the optical element LZ by using holding members 11 and 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus for manufacturing an electronic device such as a semiconductor device, a liquid crystal display device, an image pickup device (such as a CCD), or a thin film magnetic head.

[0002]

2. Description of the Related Art In a photolithography process for manufacturing an electronic device, an image of a circuit pattern is transferred to a substrate (photosensitive substrate) coated with a photosensitive resist, and the substrate is subjected to various processes such as development and etching. Process. The circuit pattern is formed on a mask (or reticle), and its image is transferred to a resist layer on a photosensitive substrate via an optical system of an exposure device. As the degree of integration of electronic devices increases, the photolithography process aims to manufacture higher-quality electronic devices.
Efforts have been made to improve exposure accuracy.

FIG. 8 schematically shows an example of the entire configuration of an exposure apparatus for manufacturing a semiconductor device. An energy beam (exposure beam) IL from the exposure light source is applied to a predetermined illumination area on the mask (reticle R) via the illumination system 51 with a uniform illumination distribution. The exposure beam IL that has passed through the reticle R is irradiated onto the photosensitive substrate (wafer) W via the projection optical system PL, whereby the image of the circuit pattern formed on the reticle R is transferred onto the photosensitive substrate W. . The reticle R is disposed with the surface on which the pattern area is formed facing downward, and is held by the reticle stage RS. The reticle stage RS includes a reticle stage drive system 52
Driven in the X, Y, and rotation directions (θ
In the direction).
Further, the position of reticle stage RS is detected by an interferometer 53 as an optical device using a light beam (such as a laser beam), and reticle stage drive system 52 is controlled based on the detection result. On the other hand, the photosensitive substrate W is held on a substrate stage (wafer stage) WS. The wafer stage WS is driven by a wafer stage drive system 54, and is driven in an X direction, a Y direction, a Z direction, and a rotation direction (θ
In the direction).
Like the reticle stage RS, the position of the wafer stage WS is sequentially detected by an interferometer 55 as an optical device using a light beam (eg, laser light), and the wafer stage drive system 54 is controlled based on the detection result. You. The direction parallel to the optical axis of the projection optical system PL is the Z direction, the direction parallel to the paper surface in a plane perpendicular to the optical axis is the X direction, the direction orthogonal thereto is the Y direction, and the optical axis of the projection optical system PL is The rotation direction about the axis parallel to AX is the θ direction.

In the exposure apparatus, the reticle R or the photosensitive substrate W is positioned (aligned) in order to accurately transfer the image of the circuit pattern of the reticle R to a desired position on the photosensitive substrate W. The alignment is usually performed based on positional information on the position of the reticle R, the photosensitive substrate W, or the positions of the stages RS and WS. for that reason,
An alignment mark is provided on the reticle R, the photosensitive substrate W, and each of the stages RS and WS, and position information of the mark is detected by an optical device using a light beam. For example, the reticle alignment system RA shown in FIG.
The wafer alignment system WA detects the position in the X and Y directions of the wafer mark WM on the photosensitive substrate W and the fiducial mark FM on the wafer stage WS. is there. Further, in the exposure apparatus, in order to focus the surface of the wafer W on the image forming plane of the projection optical system PL and the image forming plane of each alignment system (reticle alignment system, wafer alignment system, etc.),
The height position (focus amount) of the surface of the wafer W in the Z direction is detected using a light beam by an optical device. For example, a focus position detection system 60 shown in FIG. And a light-receiving system 62 for receiving light through the slit of the projection optical system PL. The height in the Z direction of the surface of the wafer W with respect to the imaging plane of the projection optical system PL is determined based on a signal obtained from the reflected light from the surface of the wafer W. Detect the position (focus amount). The control device 65 shown in FIG. 8 controls the entire device as a whole, and includes a CPU (Central Processing Unit), an RO
It comprises a microcomputer (or minicomputer) including M (read only memory), RAM (random access memory) and the like.

FIG. 9 shows the above-described interferometers 53 and 55, a reticle alignment system RA, a wafer alignment system WA,
2 shows an example of a partial configuration of an optical device such as a focus position detection system 60. A plurality of optical elements such as a lens LZ and a prism BS (such as a beam splitter) or a mirror DM (such as a dichroic mirror) are arranged on the optical path of the light beam. In the optical device of FIG. 9, the lens LZ includes a surface (including an edge) through which the light beam passes and another surface (including the edge) on the opposite side formed by a plurality of members (ring rings 70) formed in an annular shape. , 71).
Further, the prism BS and the mirror DM are held by bonding most of at least one surface (or edge) to another object with an adhesive.

[0006]

In the optical apparatus provided in the above-described conventional exposure apparatus, the optical element is held in a state where a wide area on one surface is in contact with another object.
For this reason, distortion is likely to occur inside the optical element due to the influence of deformation of another object (including an adhesive) in contact with the optical element and uneven holding force, which may cause deterioration of optical characteristics.

For example, in the case of the lens LZ shown in FIG.
The pressing force of the pressing rings 70 and 71 acts on each of the two surfaces (curved surfaces here) facing each other. This force acts in the direction of pressing each other across the lens LZ, and acts in the circumferential direction for each surface of the lens LZ. Therefore, the position where the force is strongly applied between the two opposing surfaces is likely to shift in the circumferential direction. When a displacement occurs in the distribution of force between the two surfaces, a bending moment is generated inside the lens LZ, and the lens LZ is distorted.
This may cause aberration.

Further, in the case of the prism BS and the mirror DM shown in FIG. 9, most of one surface is bonded with an adhesive, so that the adhesive is deformed at the time of curing or holds the optical member. When an object is deformed due to thermal expansion or the like, uneven force accompanying the deformation acts on the entire surface to which the object is bonded. At this time, since the prism BS and the mirror DM receive forces in various directions over a wide range of the bonded surface, a bending moment is easily generated inside. When distortion occurs in the prism BS or the mirror DM due to the bending moment, it causes a birefringence of the light beam, a shift in the reflection direction, or a change in the waveform of the light beam. For example, as shown in FIG. 9B, a beam splitter B that separates a linearly polarized light beam into P-polarized light and S-polarized light.
When the above-mentioned distortion occurs in S, a part of the S-polarized light that should be reflected is transmitted because the polarized light component becomes elliptical due to the birefringence, and the leaked light ΔS interferes with the P-polarized light and causes noise. turn into. In particular, in the above-described interferometer that detects the position information of the stage device, such leakage light directly affects the reduction in detection accuracy, and therefore it is preferable to suppress the leakage light as much as possible.

The present invention has been made in view of the above circumstances, and suppresses the occurrence of distortion of an optical element disposed on the optical path of a light beam, and enhances the position information of an object or a movable body by an optical device. The purpose is to detect with high accuracy.

[0010]

According to the present invention, there is provided an exposure apparatus for transferring an image of a pattern formed on a first object (R) onto a second object (W).
A movable body (RS, WS) holding the first object (R) or the second object (W), and the first object (R), the second object (W), and the movable body (RS, An optical device (RA, WA, 53, 55, 60) for detecting at least one position information among the optical devices (WS, WS) using a light beam;
Are optical elements (LZ,
BS, DM) and holding members (11, 12) for holding the optical elements (LZ, BS, DM) in contact with one surface of the optical elements (LZ, BS, DM) at three points. And In this exposure apparatus, the contact point between one surface of the optical element and the holding member is limited to three points. Therefore, even if the holding member is deformed or an uneven holding force is generated, almost no bending moment is generated inside the optical element. Therefore,
Generation of distortion of the optical element is suppressed.

In this case, the holding members (11,
12) has three surfaces on one surface (13) of the optical element (LZ) and another surface (14) opposed to the surface (13), respectively.
The optical element (LZ) is held in contact at a point, and the respective contacts between the holding members (11, 12) and the optical element (LZ) are in a positional relationship facing each other with the optical element (LZ) interposed therebetween. You may. In this case, the opposing 2 in the optical element
Between the two surfaces, the force of the holding member sandwiches the optical element,
Acts to push on the same axis. Therefore, generation of a bending moment in the optical element due to the force is suppressed.

Further, one surface (1) of the optical element (LZ)
3, 14) are provided with stepped surfaces (13a, 14a) in regions of the one surface (13, 14) outside the optically effective region, and the holding members (1) are provided on the stepped surfaces (13a, 14a).
1, 12) may touch. In this case, since the portion receiving the force from the holding member is separated from the optically effective area of the optical element, the occurrence of distortion in the effective area is suppressed.

In the above exposure apparatus, the holding member (20) has a projection (21) in contact with the optical element (BS), and the projection (21) and the optical element (BS).
And a hole (23) into which an adhesive for joining the two is injected. In this case, the optical element is held by the protrusion of the holding member being in contact with one surface of the optical element and being bonded by an adhesive. Here, the “hole” is a space into which the adhesive is injected, and includes a groove.

In this case, the hole (23) is provided to penetrate the holding member (20), and the optical element (BS) and the projection (21) are in contact with the optical element (21). The adhesive may be supplied from a side different from the side in contact with (BS). In this case, the excess adhesive stays in the hole, and the leakage of the adhesive into the optical path space is suppressed.

In the above exposure apparatus, the holding members (31, 32) may hold the optical element (BS) via an elastic body (30). In this case, the deformation of the holding member and the resulting non-uniform force are absorbed by the elastic body, and the generation of a bending moment inside the optical element is reliably prevented.

In this case, the elastic body (30)
May be made of a member subjected to a chemical clean treatment. In this case, the elastic body (30) is unlikely to become a contamination source, and the degree of chemical cleanness of the optical path space is maintained.

[0017]

Next, an embodiment of the present invention will be described. 1 and 2 schematically show an example of a holding structure for holding a lens LZ as an optical element used in an optical device. A circular lens LZ and press rings 11 and 12 as holding members for holding the lens LZ are disposed in a lens barrel 10 of the optical device. The lens LZ is
Two curved surfaces 13 facing each other and formed in a convex shape,
The curved surfaces 13 and 14 are arranged such that the centers of the curved surfaces 13 and 14 substantially coincide with the optical axis of the light beam in the optical device. Further, the press rings 11 and 12 are formed of annular members, and the outer diameter thereof is formed to be substantially the same as the inner diameter of the lens barrel 10. At least one end face of the press rings 11 and 12 has a projection 1 as a seat for supporting the lens LZ.
5 are formed on each end face. FIG.
As shown in (a) and (b), the three projections 15
Have a predetermined protruding height, a minute width (for example, 1 mm or less), and a radially extending seating surface 16, and are spaced apart from each other by a predetermined interval (for example, 120 ° in the circumferential direction) in the circumferential direction.

Further, as shown in FIG.
A fixing portion 17 is provided on the inner peripheral surface of the base member 1 as a reference for positioning the pressing rings 11 and 12 in the axial direction. The pressing ring 11, the lens LZ, and the pressing ring 12 are sequentially inserted into the lens barrel 10, pressed against the fixing part 17, and the pressed state is fixed by the fixing member 18 screwed to the lens barrel 10, The lens LZ is held and fixed inside the lens barrel 10. Ring ring 1
The positional relationship (projections 15, 12) is that the projections 15 face each other and face each other across the lens LZ.
Are positioned on the same axis parallel to the optical axis across the lens LZ). The positioning of the press rings 11 and 12 around the axis can be performed, for example, by providing marks such as scribe lines on the outer peripheral surfaces of the lens barrel 10 and the press rings 11 and 12 in advance and observing each mark while observing each mark. It is performed by making them coincide with each other on the same axis, or by mechanically aligning the inner peripheral or outer peripheral surfaces of the lens barrel 10 and the pressing rings 11 and 12 by applying a guide process.

In the holding structure of the present embodiment, a part (edge or the like) of the seating surface 16 of each of the three protrusions 15 of the pressing ring 11 or the pressing ring 12 is in contact with the curved surfaces 13 and 14 of the lens LZ.
One press ring 1 on one curved surface 13, 14 of the lens LZ.
Locations (contact points) where the points 1 and 12 contact each other are limited to three points. As described above, since the contact points are in a positional relationship to face each other with the lens LZ interposed therebetween, the pressing force by the press ring 11 and the press ring 12 acts so as to press on the same axis with the lens LZ interposed therebetween. Therefore, the lens LZ due to the pressing force
The generation of a bending moment inside is suppressed.

Generally, a lens is required to have high accuracy in the curvature of the curved surface. As described above, in the holding structure of the present example, since the generation of a bending moment inside the lens LZ when the lens LZ is held is suppressed, the lens LZ is unlikely to be distorted, and the curved surfaces 13 and 14 of the lens LZ. Can be kept constant. In addition, the press ring 11, 1
The contact points between the curved surfaces 2 and the curved surfaces 13 and 14 are regions where curvature accuracy is particularly required, that is, optically effective regions (in the curved surfaces 13 and 14) in order to reliably suppress generation of distortion due to holding force. For example, it is desirable to be located as far away as possible from a region through which a light beam passes). Further, as shown in FIG. 3, stepped surfaces 13a and 14a having different heights in the optical axis direction from other regions are provided in regions of the curved surfaces 13 and 14 of the lens LZ which are outside the optically effective regions. The pressing rings 11, 12 may be pressed against the step surfaces 13a, 14a. In the case of FIG. 3, the above-mentioned contact point can be easily set at a position away from the optically effective area of the lens LZ without increasing the size of the lens LZ. for that reason,
The influence of the pressing force by the pressing rings 11 and 12 on the optically effective area is further reduced, and the generation of distortion in that area is reliably suppressed. Note that, here, a circular lens having two convex curved surfaces is shown as an optical element, but the present invention is not limited to this, and the holding structure of this example has a concave curved surface and a curved surface. The present invention is applied to optical elements having various shapes, such as a flat one having no shape and a whole having a rectangular shape.

Next, FIG. 4 schematically shows an example of a holding structure for holding a prism (here, a beam splitter BS) as an optical element used in an optical device (for example, an interferometer). The beam splitter BS is held and fixed to a pedestal 20 installed on a main body (a housing or the like) of the optical device. In the holding structure of this example, the pedestal 20
3 as a seat to support the beam splitter BS on one side
A projection 21 is formed, and the projection 21 and one surface (bottom surface) of the beam splitter BS are joined by an adhesive. The three protruding portions 21 are formed, for example, in a prismatic or cylindrical shape so as to form a seating surface 22 having a small area at a predetermined protruding height, and are arranged at predetermined intervals in the plane direction. I have. Here, the beam splitter BS is composed of two optical members joined to each other,
The surface of the member coupled to the protrusion 21 is provided so as to protrude from other surfaces.

As shown in FIG. 4C, each projection 21 is provided with a hole 23 into which an adhesive AD for connecting the projection 21 and the beam splitter BS is supplied. In the present example, the hole 23 is provided through the pedestal 20. The adhesive AD is applied in a state where one surface (bottom surface) of the beam splitter BS and the bearing surface 22 of the projection 21 are in contact with each other.
The light is injected into the hole 23 from an opening on the opposite side from the side in contact with the beam splitter BS. As a result, the adhesive AD adheres and cures only to the inner peripheral surface of the hole 23 of the protrusion 21 and a part of the bottom surface of the beam splitter BS facing the hole 23. Therefore, the bottom surface of the beam splitter BS and the seat surface 22 of the projection 21 are in direct contact with each other, and the excess adhesive A
D stays inside the hole 23. Therefore, leakage of the adhesive AD into the optical path space is prevented, and contamination in the space is suppressed. Further, even when the adhesive AD contracts during curing, the bottom surface of the beam splitter BS and the seat surface 2
2 is maintained as it is, and the attitude of the beam splitter BS does not easily collapse. In addition, in the holding structure of this example, since the contact point between the bottom surface of the beam splitter BS and the pedestal 21 is limited to three points, the relative positional relationship between the three contact points is slightly increased with the curing of the adhesive. Even when the beam splitter BS changes, the generation of the bending moment inside the beam splitter BS is suppressed even though the entire beam splitter BS is slightly inclined, and no distortion occurs. Note that the overall inclination of the beam splitter BS can be corrected by adjusting the mounting posture of the pedestal 20. Further, by using a material having elastic properties after curing as the adhesive AD, the adhesive AD can absorb slight deformation of the pedestal 21 due to thermal deformation or the like. Further, as the adhesive, a light beam used in an optical device or an exposure beam IL irradiated on a reticle or a wafer in an exposure device is attenuated, and optical characteristics (transmission characteristics) of an optical system such as an illumination system or a projection optical system are used. Rate and aberration)
A substance (such as a fluorine-based substance) that does not generate impurities (such as an organic substance) that fluctuates is used. FIG.
As shown in (c), by providing a step in the hole 23 so that the inside diameter of the side where the adhesive is injected is larger than the side in contact with the beam splitter BS, the injection of the adhesive can be easily performed. At the same time, the excess adhesive can be reliably retained inside the hole 23 to prevent leakage to the outside. Such a holding structure using an adhesive is preferably used, for example, when arranging an optical element in a limited narrow installation space. Further, according to this embodiment, by suppressing the occurrence of distortion of the beam splitter, it is possible to suppress the leakage light ΔS shown in FIG. 9 described above. Therefore, generation of noise in the interferometer that detects the position information of the stage device is suppressed.

FIG. 5 schematically shows another example of a holding structure for holding the beam splitter BS. In FIG. 5, the beam splitter BS is held and fixed by being sandwiched between two pedestals 31, 32 via a spring 30 as an elastic body. That is, each pedestal 3
On one surface of the beam splitter BS, three projections 33 are formed as seats for supporting the beam splitter BS, and each projection of the pedestals 31 and 32 is formed on one surface of the beam splitter BS and the other surface opposed thereto. The parts 33 are in contact with each other, and the state is fixed by the screw member 34 via the spring 30. Further, the projection 33 of the pedestal 31 and the projection 33 of the pedestal 32 have a positional relationship to face each other with the beam splitter BS interposed therebetween. The spring 30
Attenuates a light beam used in an optical device or an exposure beam IL used in an exposure device, and changes optical characteristics (such as transmittance and aberration) of an optical system such as an illumination system and a projection optical system. A member with little generation of impurities, for example, a metal or resin member subjected to a chemical clean treatment is used. Specifically, it is a metal whose surface is coated with Teflon (registered trademark) or a fluorine-based resin subjected to secondary vulcanization. In the holding structure of this embodiment, similarly to the above-described embodiment, the projections 33 of the pedestals 31 and 32 contact and fix and hold three points on one surface of the beam splitter BS as an optical element. And the occurrence of distortion of the beam splitter BS is suppressed. In addition, since the beam splitter BS is held via the spring 30 as an elastic body, the spring 30 easily and reliably absorbs a slight deformation of the pedestals 32 and 33 due to thermal deformation or the like and an uneven force associated therewith. be able to. Further, the use of an adhesive which is likely to cause contamination can be avoided.

Next, FIG. 6 schematically shows an example of a holding structure for holding a mirror (here, a plate-shaped dichroic mirror DM) as an optical element used in the optical device. The holding structure of this example is substantially the same as the holding structure of the beam splitter shown in FIG. 5, and the dichroic mirror DM has three projections 41 via a spring 40 as an elastic body. Two pedestals 42, 43
It is held and fixed by being sandwiched between. The dichroic mirror DM has a strict surface accuracy required for its reflection surface, and a slight distortion thereof is likely to cause deterioration of the optical characteristics of the entire optical device. The holding structure of the present embodiment includes the three-point supporting structure described above and the spring 4 as an elastic body.
Due to the absorption effect of 0, high surface accuracy of the dichroic mirror DM can be reliably maintained.

FIG. 7 shows a dichroic mirror DM.
3 schematically shows another example of the holding structure for holding the. In the holding structure of this embodiment, a plurality of spherical members 50 are used instead of the protrusions in the above-described embodiment. Each of the spherical members 50 is housed in a through-hole 52 provided on the one wall of the housing body 51 for housing the dichroic mirror DM in the cavity and the other wall facing the housing 51 in three through holes. Further, the spherical member 50 housed on one wall of the housing body 51 and the spherical member 50 housed on the other wall are arranged in a positional relationship facing each other with the dichroic mirror DM interposed therebetween. The dichroic mirror DM is held and fixed by being sandwiched in a pressed state by a pedestal 53 and a thin pressing member 54 via a spherical member 50. In the holding structure of this example, spherical members 50 are provided at three places on one surface of a dichroic mirror DM as an optical element.
Point contact, the dichroic mirror DM is held in an ideal three-point support state. Further, slight deformation of the container 51 and the pedestal 53 due to thermal deformation or the like is absorbed by the bending of the pressing member 54. As a result, distortion of the dichroic mirror DM is reliably suppressed.

The holding structure of the optical element shown in each of the above-described embodiments corresponds to the interferometer 5 provided in the exposure apparatus shown in FIG.
3, 55, and are applied to optical devices such as a reticle alignment system RA, a wafer alignment system WA, and a focus position detection system 60. In such an optical device, since the occurrence of distortion of the optical element arranged on the optical path of the light beam is suppressed by each of the holding structures, a decrease in optical characteristics is small, and the reticle R, the photosensitive substrate (wafer) W, and Position information of the reticle stage RS and the wafer stage WS that hold it can be detected with high accuracy.

The operation procedure described in the above embodiment, or the various shapes and combinations of the constituent members are merely examples, and various changes may be made based on process conditions and design requirements without departing from the gist of the present invention. It is possible. The present invention includes the following modifications.

The optical elements held by the holding structure are not limited to the lenses, beam splitters, and dichroic mirrors described above, and various optical elements used in optical devices can be applied. Further, the holding structure is not limited to the structure shown in the above-described embodiment, and is appropriately determined according to the installation space of the optical element, the characteristics of the optical element, and the required accuracy.

As a material of the above-mentioned holding member such as a press ring and a pedestal, a resin or a metal member which is provided with a chemical clean measure is preferably used. In addition, by using a material that does not easily generate thermal distortion, such as an invar material, deformation of the pedestal due to generation of heat can be prevented, and generation of distortion in the optical element and disturbance of the attitude of the optical element can be suppressed.

The projection as a seat for supporting the optical element is not limited to a particular processing method. For example, the projection can be formed by welding to the holding member or by cutting.

When a step surface is provided on one surface of the optical element, the shape of the step surface is not limited to the shape shown in FIG. That is, in the lens LZ shown in FIG.
The step surfaces 13a and 14a are formed over the entire circumferential direction, but the step surfaces may be provided at least at locations where the protrusions of the holding member are in contact.

The optical device to which the present invention is applied may be any device that can detect positional information of a movable body such as a mask (reticle), a photosensitive substrate (wafer), and a stage for holding the same. Various things other than a thing are applicable. For example, the present invention can also be applied to a focus position detection system 75 indicated by a two-dot chain line in FIG. 8, and the focus position detection system 75 controls the orientation of the pattern surface of the reticle R in order to control the orientation of the reticle R surface. This is for detecting the height position in the Z direction. Further, the structure for holding the optical element according to the present invention may be applied to only a part of the optical device.

As a technique for detecting positional information of a mask (reticle), for example, an illumination light (exposure beam) for exposure is applied to a mark formed on the mask, and an optical image of the mark is exposed to a CCD (Charge Coupled Device). A VRA (Visual Reticle Align) that converts an image signal by an image pickup means such as a camera and measures mark position information based on the image signal.
ment) method is known. Also, photosensitive substrate (wafer)
As a technique for detecting the position information of a mark, an LSA (Lase) that irradiates a mark on a photosensitive substrate with a laser beam and measures the position information of the mark using light diffracted or scattered by the mark is used.
r Step Alignment) method, irradiates the mark on the photosensitive substrate with light with a wide wavelength bandwidth using a halogen lamp or the like as a light source.
The optical image is converted into an image signal by an image pickup means such as a CCD camera, and the FIA (Field Image Alignment) method of measuring mark position information based on the image signal. The frequency is slightly changed to a mark on a photosensitive substrate. An LIA (Laser Integer) that irradiates laser light from two directions, causes the two generated diffracted lights to interfere with each other, and measures mark position information from the phase.
Rferometric Alignment) is known. The present invention can be applied to any type of optical device. In particular, in an optical device using the VRA type or FIA type technology, the optical element used is relatively large, so that the present invention has a higher effect. Is obtained.

In the exposure apparatus to which the present invention is applied, a mask (reticle) is exposed to exposure illumination light (exposure beam).
The method is not limited to the scanning exposure method (for example, a step-and-scan method) in which the mask and the substrate (wafer) are relatively moved, and the pattern of the mask is placed on the substrate while the mask and the substrate are almost stationary. A static exposure method for transferring, for example, a step-and-repeat method may be used. Further, a step-and-step method for transferring a pattern to each of a plurality of shot areas having overlapping peripheral portions on the substrate.
The present invention is also applicable to a stitch type exposure apparatus and the like. Further, the projection optical system may be any of a reduction system, an equal magnification system, and an enlargement system, and may be any of a refraction system, a catadioptric system, and a reflection system. Further, the present invention can be applied to, for example, a proximity type exposure apparatus that does not use a projection optical system.

In the exposure apparatus to which the present invention is applied, g-line, i-line, KrF excimer laser light (248 nm), and ArF excimer laser light (193n) are used as exposure illumination light.
m), F ₂ laser light (157 nm), laser light, and A
not only ultraviolet light, such as r ₂ laser light, for example EUV
Light, X-ray, or a charged particle beam such as an electron beam or an ion beam may be used. Further, the light source for exposure is not limited to a mercury lamp or an excimer laser, but may be a harmonic generator such as a YAG laser or a semiconductor laser, an SOR, a laser plasma light source, an electron gun, or the like.

The exposure apparatus to which the present invention is applied is not limited to semiconductor device manufacturing, but includes liquid crystal display devices, display devices, thin-film magnetic heads, imaging devices (such as CCDs), micromachines, DNA chips, and the like. For manufacturing microdevices (electronic devices), and for manufacturing photomasks and reticles used in exposure apparatuses.

When a linear motor is used for the wafer stage or reticle stage described above, either an air levitation type using an air bearing or a magnetic levitation type using Lorentz force or reactance force may be used.
The stage may be of a type that moves along a guide or a guideless type that does not have a guide.
Further, when a plane motor is used as the stage driving device, one of the magnet unit (permanent magnet) and the armature unit is connected to the stage, and the other of the magnet unit and the armature unit is connected to the moving surface side of the stage ( Base).

Further, the reaction force generated by the movement of the wafer stage is mechanically moved to the floor (ground) using a frame member as described in Japanese Patent Application Laid-Open No. 8-166475.
You may escape to The present invention is also applicable to an exposure apparatus having such a structure.

The reaction force generated by the movement of the reticle stage may be mechanically released to the floor (ground) using a frame member as described in JP-A-8-330224. The present invention is also applicable to an exposure apparatus having such a structure.

Further, the exposure apparatus to which the present invention is applied controls various subsystems including each component described in the claims of the present application so as to maintain predetermined mechanical accuracy, electrical accuracy, and optical accuracy. And manufactured by assembling. Before and after this assembly, adjustments to achieve optical accuracy for various optical systems, adjustments to achieve mechanical accuracy for various mechanical systems, and various electric systems to ensure these various accuracy Are adjusted to achieve electrical accuracy. The process of assembling the exposure apparatus from various subsystems includes mechanical connections, wiring connections of electric circuits, and piping connections of pneumatic circuits among the various subsystems. It goes without saying that there is an assembling process for each subsystem before the assembling process from these various subsystems to the exposure apparatus. When the process of assembling the various subsystems into the exposure apparatus is completed, comprehensive adjustment is performed, and various precisions of the entire exposure apparatus are secured. It is desirable that the manufacture of the exposure apparatus be performed in a clean room in which the temperature, cleanliness, and the like are controlled.

The electronic device has the functions and functions of the device.
A process of performing performance design, a process of manufacturing a mask (reticle) based on this design step, a process of manufacturing a substrate such as a wafer from raw materials, a substrate processing process of exposing a mask pattern to a photosensitive substrate by the above-described exposure apparatus, Device assembly process (dicing process, bonding process,
(Including a package process) and an inspection process.

[0042]

As described above, according to the present invention,
Since the holding member holds the optical element in contact with one surface of the optical element at three points, the occurrence of distortion due to bending moment inside the optical element is suppressed. Therefore, the position information of the object or the movable body can be detected with high accuracy by the optical device.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing an example of a lens holding structure in an optical device provided in an exposure apparatus according to the present invention.

FIG. 2A is a cross-sectional view illustrating the holding structure of FIG. 1;
(B) is a top view showing a holding member.

3A is a cross-sectional view illustrating a holding structure in which an optical element is provided with a step surface, and FIG. 3B is a plan view illustrating the optical element.

FIG. 4 is a diagram illustrating an example of a holding structure of a beam splitter.

FIG. 5 is a diagram illustrating another example of a holding structure of a beam splitter.

FIG. 6 is a view showing an example of a dichroic mirror holding structure.

FIG. 7 is a view showing another example of a dichroic mirror holding structure.

FIG. 8 is a diagram schematically showing a configuration of an exposure apparatus.

FIG. 9 is a view showing a holding structure of an optical element in a conventional exposure apparatus.

[Explanation of symbols]

 R reticle (first object) W wafer (second object) RS reticle stage (movable body) WS wafer stage (movable body) RA reticle alignment system WA wafer alignment system LZ lens BS prism DM mirror AD adhesive 11 and 12 press ring (Holding member) 13, 14 curved surface 13a, 14a step surface 20 pedestal (holding member) 21 protrusion 23 hole 31, 32 pedestal (holding member) 30 spring (elastic body) 53, 55 interferometer 60 focus position detection system

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) G03F 9/00 G02B 7/18 C H01L 21/30 515Z F term (reference) 2F065 AA20 BB27 CC20 CC25 FF04 FF42 FF48 FF51 GG02 GG04 GG23 LL04 LL20 LL46 PP12 QQ28 2H043 BC03 BC05 BC06 5F046 CB20 CC16 DB05 FB12 FB20

Claims (7)

[Claims] An exposure apparatus for transferring an image of a pattern formed on a first object onto a second object, comprising: a movable body that holds the first object or the second object;
An optical device that detects position information of at least one of the first object, the second object, and the movable body using a light beam, wherein the optical device is disposed on an optical path of the light beam. An exposure apparatus, comprising: an optical element, and a holding member that holds the optical element in contact with one surface of the optical element at three points. 2. The holding member holds the optical element in contact with one surface of the optical element and another surface facing the surface at three points, respectively, and holds each of the holding member and the optical element. 2. The exposure apparatus according to claim 1, wherein the contact points have a positional relationship facing each other across the optical element. 3. The optical device according to claim 1, wherein a step surface is provided on one surface of the optical element outside of the optically effective region of the one surface, and the holding member is in contact with the step surface.
Alternatively, the exposure apparatus according to claim 2. 4. The holding member is provided with a protrusion that contacts the optical element, and a hole into which an adhesive for connecting the protrusion and the optical element is supplied. The exposure apparatus according to claim 1, wherein 5. The hole is provided so as to penetrate the holding member, and in a state where the optical element is in contact with the projection, the adhesive is supplied from a side different from a side in contact with the optical element. The exposure apparatus according to claim 4, wherein: 6. The exposure apparatus according to claim 1, wherein the holding member holds the optical element via an elastic body. 7. The exposure apparatus according to claim 6, wherein the elastic body is made of a member subjected to a chemical clean processing.