WO2003054936A1

WO2003054936A1 - Gas purging method and exposure system, and device production method

Info

Publication number: WO2003054936A1
Application number: PCT/JP2002/013425
Authority: WO
Inventors: Naomasa Shiraishi
Original assignee: Nikon Corporation
Priority date: 2001-12-21
Filing date: 2002-12-24
Publication date: 2003-07-03
Also published as: JPWO2003054936A1; AU2002366929A1; TWI222668B; TW200307979A

Abstract

When gas-purging a space between a specific object (RST or R) disposed on the optical path of light (EL) having a specified wavelength and an optical device (ILU), a shielding member (22) for shielding from outside air a space (IM) between the optical device and the specific object is disposed with a specified clearance kept formed with respect to the specific object, and a specific gas lower in absorption characteristics with respect to the light than an absorbing gas is supplied to the space (IM) via an air supply pipe (60) connected to the shielding member. An inner gas in the space (IM) is exhausted to the outside via an exhaust pipe (61) connected to the shielding member. Accordingly, the use of a small shielding member capable covering a space between an optical device and a specific object enables gas substituting almost as accurate as when a large, heavy air-tight shielding vessel is used.

Description

Specification

Gas purge method, exposure apparatus, and device manufacturing method

The present invention relates to a gas purging method, an exposure apparatus, and a device manufacturing method, and more particularly, to a gas purging method and a gas purging method for purging a space between an object disposed on an optical path of light having a predetermined wavelength and an optical apparatus. And a device manufacturing method using the exposure apparatus. Background art

2. Description of the Related Art Conventionally, in a lithographic process for manufacturing electronic devices such as semiconductor devices (integrated circuits) and liquid crystal display devices, various exposure apparatuses for forming fine patterns of electronic devices on a substrate have been used. In recent years, especially from the viewpoint of productivity, the pattern of a photomask (mask) or reticle (hereinafter collectively referred to as “reticle”) formed by enlarging the pattern to be formed by about 4 to 5 times is projected onto a projection optical system. A reduction projection exposure apparatus that performs reduction transfer onto a substrate to be exposed such as a wafer (hereinafter, referred to as a “wafer”) through a system is mainly used.

In this type of projection exposure apparatus, the exposure wavelength has been shifted to shorter wavelengths in order to realize high resolution in response to miniaturization of integrated circuits. At present, the wavelength of the KrF excimer laser is 248 nm, but the shorter wavelength of 1193 nm of the ArF excimer laser is entering the practical stage. Then, recently, further F 2 laser and the wavelength 1 5 7 nm short wavelength, the A r ₂ laser having a wavelength of 1 2 6 nm, projection using a light source emitting light in a wavelength band so-called vacuum ultraviolet region Exposure apparatuses have also been proposed.

Such vacuum ultraviolet light having a wavelength of 180 nm or less is generated by oxygen and water vapor in the atmosphere. Receive severe absorption. For this reason, in an exposure apparatus that uses vacuum ultraviolet light as exposure light, gas in the space hardly absorbs the exposure light because light-absorbing substances such as oxygen and water vapor are excluded from the space on the optical path of the exposure light. It is necessary to perform gas replacement (gas purging) with a rare gas such as nitrogen or helium. For example, in an exposure system that uses an F 2 laser with an oscillation wavelength of 157 nm as a light source, it is said that the residual oxygen concentration must be kept below 1 ppm over most of the optical path from the laser to the wafer. . In addition, high resolution can be realized not only by shortening the exposure wavelength but also by increasing the numerical aperture (N.A.) of the optical system. The development of A. However, in order to achieve high resolution, it is necessary to reduce the aberration of the projection optical system in addition to increasing the size of the projection optical system. For this reason, in the manufacturing process of the projection optical system, wavefront aberration measurement using light interference is performed, the amount of residual aberration is measured with an accuracy of about 1100 of the exposure wavelength, and the projection optical system is measured based on the measured value. The system is being adjusted.

Such an increase in NA and reduction in aberrations are easier to achieve in an optical system with a smaller field of view. However, as for the exposure apparatus, the processing capability (throughput) is improved as the field of view (exposure field) is larger. Therefore, in order to obtain a substantially large exposure field using a projection optical system with a small field of view but a large N.A., a relative scan of the reticle and wafer is performed during exposure while maintaining the imaging relationship. For example, a scanning projection exposure apparatus, for example, a step-and-scan scanning projection exposure apparatus (ie, a so-called scanning stepper) has become the mainstream in recent years.

Incidentally, in the above-described exposure apparatus using vacuum ultraviolet light as a light source, the concentration of residual oxygen and water vapor in the space near the reticle also needs to be suppressed to about 1 ppm or less. As a method of realizing this, a method of covering the entire reticle stage holding the reticle with a large airtight shielding container (reticle stage chamber) and purging the entire inside (including the reticle stage and the reticle) with gas is also conceivable. Only However, when such a shielding container is used, the exposure apparatus becomes larger and heavier, and the installation area (footprint) per exposure apparatus in a clean room of a semiconductor factory becomes larger, and equipment costs (or equipment costs) increase. As a result, the productivity of the semiconductor device is reduced due to an increase in running cost. In addition, access to the vicinity of the reticle becomes difficult, and workability during maintenance of the reticle stage and the like decreases, so that the time required for maintenance increases, and in this regard, the productivity of semiconductor elements also decreases.

In particular, a scanning projection exposure apparatus has a large reticle stage because it is necessary to scan the reticle at high speed during exposure, and the shielding container (reticle stage chamber) that covers the entire large reticle stage is becoming larger. I will.

In addition, gas purging of the space near the reticle is not only a problem for the projection exposure apparatus, but also for an inspection optical apparatus for measuring aberration of a projection optical system mounted on the projection exposure apparatus.

The present invention has been made under such circumstances, and a first object of the present invention is to provide a large and heavy airtight space for efficient gas replacement of a space between an object arranged on an optical path of light and an optical device. An object of the present invention is to provide a gas purging method which can be realized without using a mold shielding container.

A second object of the present invention is to provide an exposure apparatus capable of improving exposure accuracy while suppressing an increase in the size and weight of the apparatus.

A third object of the present invention is to provide a device manufacturing method capable of improving the productivity of a highly integrated device. Disclosure of the invention

According to a first aspect of the present invention, there is provided a gas purging method for gas purging a space between an object disposed on an optical path of light having a predetermined wavelength and an optical device, the method comprising: at least holding the object and the object; Between a specific object that is one of the holding members Arranging a shielding member for shielding a space between the optical device and the object from outside air in a state in which a predetermined first clearance is formed; specifying that the absorption characteristic for the light is lower than that of the absorbing gas Supplying a gas to a space inside the shielding member through an air supply opening formed in the shielding member.

Here, the absorptive gas is a general term for a gas having a large absorption characteristic with respect to the light having the predetermined wavelength (light used in an optical device). For example, the light is a vacuum having a wavelength of 120 nm to 180 nm. In the case of ultraviolet light, a gas containing a light-absorbing substance such as oxygen, water vapor, or a hydrocarbon that strongly absorbs the vacuum ultraviolet light is applicable. In this specification, the term “absorbable gas” is used in this sense. Since general air (atmosphere) also contains a large amount of oxygen and water vapor, it should be treated as an absorbent gas. Therefore, the absorbing gas differs depending on the wavelength (predetermined wavelength) of the light. According to this, the shielding member is disposed in a state where a predetermined first clearance is formed between at least the object and a specific object that is one of the holding members that hold the object. By setting the clearance to an appropriate size, the space inside the shielding member between the object disposed on the optical path of the light of the predetermined wavelength and the optical device can be shielded from outside air in a somewhat airtight state. . Then, a specific gas (hereinafter, referred to as “low-absorbing gas” as appropriate) having a lower absorption characteristic with respect to the light than the absorbing gas through an air supply opening formed in the shielding member in the space inside the shielding member. Described) is supplied. This makes it possible to replace the gas in the space on the optical path between the object and the optical device, that is, the gas in the space inside the shielding member, with a low-absorbing gas. Thereby, the absorbent gas can be expelled (purged) from the space. Therefore, it is possible to achieve high-precision gas replacement of the space between the optical device and the object disposed on the optical path of the light without using a large and heavy airtight shielding container. In other words, according to the present invention, a large and heavy airtight shielding container is used only by using a small shielding member capable of covering the space between the optical device and the object. Gas replacement with almost the same high accuracy as that in the case of using is possible.

In this case, the method may further include a step of exhausting gas in a space inside the shielding member to the outside through an exhaust opening formed in the shielding member.

In the first gas purging method of the present invention, the first clearance may be about 3 mm or less.

In this case, a predetermined gas is supplied into the first clearance via an air supply port formed on an end face of the shielding member facing the specific object, and the gas in the first clearance is supplied to the end face. The method may further include a step of exhausting the space to the outside through an exhaust port formed outside the air supply port.

In the first gas purging method of the present invention, the shielding member may reduce transmission of vibration to the optical device.

In this case, the shielding member may be arranged in a state where a predetermined second clearance is formed between the shielding member and the optical device.

In this case, the second clearance can be about 3 mm or less.

In this case, a predetermined gas is supplied into the second clearance via an air supply port formed on an end face of the shielding member facing the optical device, and the gas in the second clearance is supplied to the end face. The method may further include a step of exhausting the space to the outside through an exhaust port formed outside the air supply port.

According to a second aspect of the present invention, there is provided a gas purging method for purging a space including a light receiving surface of a photodetector used in an optical device having an optical system irradiated with light of a predetermined wavelength, One end is open and the end face around the opening of the holding member, in which the photodetector is accommodated with the light receiving surface facing the opening, is formed inside the optical device. Bonding to a part of the component through a sealing member to shield a space including a light receiving surface of the photodetector from outside air; and removing a specific gas having a lower light absorption characteristic than an absorptive gas. Supplying gas to the space through an air supply opening formed in one of the component part and the holding member, and exhausting gas in the space into an exhaust gas formed in one of the component part and the holding member. A second gas purging method, which comprises the steps of:

According to this, an end surface around the opening of the holding member that has one surface opened and accommodates the photodetector inside with the light receiving surface facing the opening is part of the component of the optical device. It couples via a seal member and shields the space including the light receiving surface of the photodetector from the outside air. For this reason, the space including the light receiving surface of the photodetector formed by the components of the optical device and the holding member is a space with good airtightness. The specific gas (low-absorbing gas) having a lower absorption characteristic with respect to light incident on the optical device and incident on the light receiving element via the optical system of the optical device than the absorbing gas is used as the component and the holding member. A gas is supplied to the space through an air supply opening formed in any of the members, and the gas in the space is exhausted to the outside through an exhaust opening formed in any of the component parts and the holding member. I do. As a result, the gas inside the space between the optical device and the light receiving surface of the photodetector is replaced with the specific gas, and light of a predetermined wavelength entering the space via the optical device is emitted from the photodetector. Until the light is received by the light receiving surface, it is hardly absorbed in the space. Therefore, it is possible to accurately detect the light amount of the photodetector, and when, for example, measuring the optical characteristics of an optical device based on the result of the light amount detection, the measurement accuracy can be improved. It is possible.

In this case, a step of forming a through hole in advance in a portion of the holding member where the photodetector is mounted; and an electric power from the photodetector through the through hole from the back side of the photodetector. And taking out the wiring to the outside. The second gas purging method of the present invention may further include a step of cooling the holding member.

In this case, the cooling of the holding member can be performed by connecting a Peltier element to the surface of the holding member on the side opposite to the photodetector.

In this case, the method may further include a step of cooling a side of the Peltier element opposite to the holding member.

In the second gas purging method of the present invention, a light transmissive member is arranged on a side of the component to which the holding member of the optical device is coupled, opposite to the holding member, and a light receiving surface of the photodetector is disposed. The method may further include a step of partitioning the containing space into a plurality of spaces.

According to a third aspect of the present invention, there is provided an exposure apparatus for transferring a pattern formed on a mask onto a substrate, comprising: an illumination optical system for illuminating the mask with light of a predetermined wavelength; the mask and the mask The illumination optics of the mask, wherein the illumination optics of the mask is disposed between a specific object, which is one of the mask holding members, and the illumination optical system, and at least a predetermined first clearance is formed between the specific object and the specific object. A first shielding member for shielding at least a first space including a region corresponding to the pattern region of the mask from the outside air on a system side; and absorbing the light through an air supply opening formed in the first shielding member. And a first gas supply system for supplying a specific gas having a characteristic lower than that of the absorbent gas to the first space.

According to this, the first shielding member disposed with a predetermined first clearance formed between at least the specific object between the specific object, which is one of the mask and the mask holding member, and the illumination optical system. Accordingly, the first space including at least a region corresponding to the pattern region of the mask on the illumination optical system side of the mask is shielded from the outside air. Then, the specific gas (low-absorbing gas) having a lower absorption characteristic with respect to light of a predetermined wavelength (exposure light) than the absorbing gas is supplied by the first gas supply system through the air supply opening formed in the first shielding member. It is supplied to the first space. As a result, the gas in the first space Replaced with a specific gas. Accordingly, it is possible to eliminate the absorbing gas that absorbs the exposure light from the first space, and the light emitted from the illumination optical system illuminates the mask without being absorbed in the first space. It is possible to suppress a decrease in the transmittance of the exposure light and realize highly accurate exposure. In this case, the first space is large and heavily sealed using only a small first shielding member that can cover the first space between the illumination optical system and the mask or the mask holding member. (Mask stage chamber) enables gas replacement with almost the same efficiency as in the case of using (mask stage chamber). Therefore, it is possible to suppress an increase in the size and weight of the device.

In this case, a projection optical system for projecting light emitted from the mask onto the substrate; and a projection optical system disposed between the specific object and the projection optical system to reduce transmission of vibration to the projection optical system. A second shielding member for shielding at least a second space including a pattern region of the mask from the outside on the projection optical system side of the mask from the outside; and an air supply opening formed in the second shielding member. And a second gas supply system that supplies the specific gas to the second space through the second gas supply system.

In this case, the second shielding member can be disposed with at least a predetermined second clearance formed between the second shielding member and the specific object. In this case, the second shielding member is formed on the first shielding member A first gas exhaust system for exhausting the gas in the first space to the outside through the provided exhaust opening; and a gas in the second space via an exhaust opening formed in the second shielding member. And a second gas exhaust system for exhausting the gas to the outside.

In the first exposure apparatus of the present invention, at least one of the first and second clearances may be about 3 mm or less.

In this case, a predetermined gas is supplied into the first clearance from an air supply port formed on an end face of the first shielding member facing the specific object, and the gas in the first clearance is supplied to the end face. The air supply port for the first space And a differential exhaust mechanism that exhausts the air to the outside through an exhaust port formed outside the air conditioner.

In the first exposure apparatus of the present invention, when at least one of the first and second clearances is about 3 mm or less, an air supply formed on an end face of the second shielding member facing the specific object. A predetermined gas is supplied from the port toward the specific object, and the gas in the second clearance is supplied to the second space on the end face via an exhaust port formed outside the supply port. A differential exhaust mechanism that exhausts to the outside can be further provided.

In the first exposure apparatus of the present invention, when a second shielding member is provided in a state where a predetermined second clearance is formed between the first shielding member and at least the specific object, the first shielding member An adjusting mechanism that is provided at an end of the specific object on the specific object side, and that is capable of adjusting the first clearance over the entire circumference of the first shielding member; and an adjusting mechanism that is provided at an end of the second shielding member on the specific object side. And an adjusting mechanism capable of adjusting the second clearance over the entire circumference of the second shielding member.

In the first exposure apparatus of the present invention, in the case where the first exposure apparatus further includes a second shielding member disposed in a state where a predetermined second clearance is formed between at least the specific object and the first shielding member, A predetermined third clearance may be formed between the second shielding member and the projection optical system.

In this case, the third clearance can be about 3 mm or less.

The first exposure apparatus of the present invention further includes a second shielding member in addition to the first shielding member, wherein a third clearance is formed between the second shielding member and the projection optical system. A predetermined gas is supplied into the third clearance from an air supply port formed on an end face of the shielding member facing the projection optical system, and the gas in the third clearance is supplied to the second space on the end face. Formed outside the air supply port It is possible to further include a differential exhaust mechanism that exhausts the air to the outside through the exhaust port.

In the first exposure apparatus of the present invention, in the case where the first exposure apparatus further includes a second shielding member disposed in a state where a predetermined second clearance is formed between at least the specific object and the first shielding member, An end surface of the first shielding member facing the specific object and an end surface of the second shielding member facing the specific object are both flat surfaces, and the surfaces of the specific object facing the respective end surfaces are both flat surfaces. It can be.

In the first exposure apparatus of the present invention, in the case where the first exposure apparatus further includes a second shielding member disposed in a state where a predetermined second clearance is formed between at least the specific object and the first shielding member, A substrate holding member for holding the substrate; a drive device for driving the mask holding member in a predetermined scanning direction; a driving device for synchronously moving the mask holding member and the substrate holding member in a predetermined scanning direction; And at least a part of the driving source may be arranged outside the first space and the second space.

In the first exposure apparatus of the present invention, when a driving device that synchronously moves the mask holding member and the substrate holding member in a predetermined scanning direction is provided, a length of the first shielding member in the scanning direction is at least. It is determined based on the approach distance in which the mask holding member moves in an acceleration area and a deceleration area before and after the synchronous movement in which the exposure is performed, and a length of the mask pattern area in the scanning direction. It can be.

In the first exposure apparatus of the present invention, in the case where the first exposure apparatus further includes a second shielding member disposed in a state where a predetermined second clearance is formed between at least the specific object and the first shielding member, A third space that is disposed between the substrate and the projection optical system and shields a third space on the projection optical system side of the substrate from outside air in a state where at least a predetermined third clearance is formed between the substrate and the projection optical system. 3 shielding members; and the third shielding portion And a third gas supply system that supplies the specific gas to the third space via an air supply opening formed in the material.

In this case, a gas exhaust system that exhausts the gas in the third space to the outside through an exhaust opening formed in the third shielding member may be further provided.

In the first exposure apparatus of the present invention, when the first, second, and third shielding members are provided, the third shielding member forms a predetermined fourth clearance with the projection optical system. It can be arranged with.

In this case, an exhaust mechanism for exhausting the gas in the fourth clearance to the outside through an exhaust port formed on an end face of the third shielding member facing the projection optical system is further provided. be able to.

In this case, the exhaust mechanism can exhaust the gas in the third space to the outside via the fourth clearance.

In this case, the third gas supply system may supply the specific gas to the third space via the fourth clearance.

In the first exposure apparatus of the present invention, when the above-described first, second, and third shielding members are provided, a predetermined gas is supplied from an air supply port formed on an end surface of the third shielding member facing the substrate. Is supplied into the third clearance, and the gas in the third clearance is exhausted to the outside of the third space on the end face through an exhaust port formed outside the air supply port. A dynamic exhaust mechanism may be further provided.

In the first exposure apparatus of the present invention, a predetermined second clearance may be formed between the first shielding member and the illumination optical system. In this case, the second clearance can be about 3 mm or less.

In the present invention, a predetermined second clearance is provided between the first shielding member and the illumination optical system. Is formed, a predetermined gas is supplied into the second clearance from an air supply port formed on an end face of the first shielding member facing the illumination optical system, and the inside of the second clearance is The air conditioner may further include a differential exhaust mechanism that exhausts the gas to the outside through an exhaust port formed outside the air supply port with respect to the first space on the end face.

In the first exposure apparatus of the present invention, the first exposure apparatus is disposed between the substrate and the projection optical system, and at least a predetermined second clearance is formed between the substrate and the projection optical system. A second shielding member that shields the second space from the outside air; and a second gas supply system that supplies the specific gas to the second space via an air supply opening formed in the second shielding member. Further provisions may be made.

In this case, a gas exhaust system that exhausts gas in the second space to the outside via an exhaust opening formed in the second shielding member may be further provided.

In the first exposure apparatus of the present invention, the second shielding member is arranged in a state where a predetermined second clearance is formed between the second shielding member and the substrate, and is provided via an air supply opening formed in the second shielding member. When a second gas supply system that supplies the specific gas to the second space is provided, the second shielding member is arranged in a state where a predetermined third clearance is formed between the second shielding member and the projection optical system. can do.

In this case, an exhaust mechanism for exhausting gas in the third clearance to the outside through an exhaust port formed on an end face of the second shielding member facing the projection optical system is further provided. be able to.

In this case, the exhaust mechanism may exhaust the gas in the second space to the outside via the third clearance.

In this case, the second gas supply system may supply the specific gas to the second space via the third clearance.

In the exposure apparatus of the present invention, in addition to the first shielding member, the second space on the projection optical system side of the substrate is provided. When a second shielding member for shielding the space from outside air is also provided, a predetermined gas is supplied into the second clearance from an air supply port formed on an end surface of the second shielding member facing the substrate, A differential exhaust mechanism for exhausting the gas in the second clearance to the outside through the exhaust port formed outside the air supply port with respect to the second space on the end face may be further provided. .

In the first exposure apparatus of the present invention, when a second shielding member that shields the second space of the substrate on the projection optical system side from the outside air is provided, the second exposure member is provided at an end of the second shielding member on the substrate side. In addition, an adjusting mechanism capable of adjusting the second clearance over the entire circumference of the second shielding member may be further provided.

The first exposure apparatus of the present invention further includes: a substrate holding member for holding the substrate; and a driving device for synchronously moving the mask holding member and the substrate holding member in a predetermined scanning direction. be able to.

In this case, the length of the first shielding member in the scanning direction is at least a running distance by which the mask holding member moves between an acceleration region and a deceleration region before and after the synchronous movement in which the exposure is performed. And the length of the pattern area of the mask in the scanning direction.

In this case, the length of the first shielding member in the scanning direction is further determined based on the length of the illumination region in which the mask is illuminated by the light in the scanning direction. Can be.

According to a fourth aspect of the present invention, there is provided an exposure apparatus for transferring a pattern of a mask illuminated with exposure light onto a substrate via a projection optical system, comprising: A second exposure apparatus that is disposed without contacting the substrate and the projection optical system, and that includes a shielding member that shields a space including an optical path of the exposure light between the substrate and the projection optical system from outside air. It is.

According to this, as the shielding member, a small shielding member that can cover a predetermined space including the optical path of exposure light between the substrate and the projection optical system is used. When the gas in the space is replaced with, for example, a low-absorbent gas, the space is almost as efficient as when a large and heavy airtight shielding container (substrate stage chamber) is used. Good gas replacement is possible. This makes it possible to remove the absorptive gas that absorbs the exposure light from the space including the optical path of the exposure light between the substrate and the projection optical system, and the light emitted from the projection optical system hardly remains in that space. Since the light is irradiated onto the substrate without being absorbed, a decrease in the transmittance of the exposure light can be suppressed. Further, the transmission of the vibration on the substrate side to the projection optical system via the shielding member is prevented. Therefore, it is possible to improve the exposure accuracy while suppressing an increase in the size and weight of the apparatus.

In this case, a space shielded by the shielding member is formed by sucking and exhausting a gas in a clearance formed between the substrate and the shielding member or between the projection optical system and the shielding member. Can be shielded from the outside air.

In this case, a specific gas whose absorption characteristic with respect to the exposure light is lower than that of the absorptive gas is set in a clearance formed between the substrate and the shielding member or between the projection optical system and the shielding member. Can be supplied. Further, in the lithographic process, by performing exposure using the exposure apparatus of the present invention, a pattern can be formed on a substrate with high accuracy, thereby manufacturing a highly integrated microdevice with a high yield. can do. Therefore, from another viewpoint, the present invention can be said to be a device manufacturing method using the exposure apparatus of the present invention. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram schematically showing a configuration of an exposure apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram schematically showing a gas pipe of the apparatus of FIG. FIG. 3A is a perspective view showing the vicinity of reticle stage RST, and FIG. 3A is a schematic sectional view showing reticle stage RS #.

FIG. 4 is a plan view showing reticle stage R S Τ.

Fig. 5 (a) is a cross-sectional view showing the portion where the lower end face of the illumination system side gas purge skirt and the reticle stage are located close to each other. It is a figure which expands and shows a part.

FIG. 6A is a cross-sectional view showing a portion where the upper end surface of the projection system-side gas purge unit and the reticle stage are arranged close to each other. FIG. 6B is a diagram showing the projection system-side gas purge skirt and the projection optical system arranged in close proximity It is sectional drawing which shows the part which was done.

FIG. 7A is a cross-sectional view showing the vicinity of a wafer gas purge skirt, and FIG. 7B is a plan view of the wafer gas purge skirt as viewed from above (+ Z side).

FIG. 8 is a diagram for explaining a configuration of a differential exhaust mechanism in a case where an illumination system-side gas purge skirt is provided so that a clearance is formed between the illumination unit and the illumination system-side gas purge skirt.

FIG. 9 is a diagram for explaining a gas purging method according to a modification.

FIG. 10 is a cross-sectional view showing an inspection unit forming a part of the inspection optical device according to the second embodiment of the present invention, together with a projection optical system and a shielding mechanism.

FIG. 11A is a cross-sectional view showing the vicinity of the lower end of an optical system support housing according to a third embodiment of the present invention, and FIG. 11B is a perspective view showing a ceramic package on which a CCD is mounted. is there.

FIG. 12 is a flowchart for explaining an embodiment of the device manufacturing method according to the present invention.

FIG. 13 is a flowchart showing the details of step 304 in FIG. BEST MODE FOR CARRYING OUT THE INVENTION

<< 1st Embodiment >> Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 to 7B. FIG. 1 schematically shows a configuration of an exposure apparatus 100 according to the first embodiment. The exposure apparatus 100 irradiates an exposure illumination light EL as an energy beam onto a reticle R as a mask, and scans the reticle R and a wafer W as a substrate in a predetermined scanning direction (here, FIG. A step of transferring the pattern of the reticle R to a plurality of shot areas on the wafer W via the projection optical system PL by synchronously moving in the Y-axis direction which is a direction orthogonal to the paper surface. That is, it is a so-called scanning stepper.

The exposure apparatus 100 includes a light source (not shown) and an illumination unit ILU as an optical device (illumination optical system), and illuminates the reticle R with illumination light for exposure (hereinafter, referred to as “exposure light”) EL. Illumination system, reticle stage RST as a mask holding member for holding reticle R, projection optical system for projecting exposure light EL emitted from reticle R onto wafer W, and ゥ as a substrate holding member for holding wafer W It is equipped with a wafer stage WST, their control system, and a support base BD that supports each component.

The support base BD includes a plurality of (for example, three or four) legs provided on the floor surface F of the clean room via a plurality of (for example, three or four) first vibration isolation units 43. A first base 34 having a lens barrel base plate (also referred to as a main frame) 34 B supported substantially horizontally by 34 A and the legs 34 A, and a top plate of the first base 34 The plurality of support members 21 provided on the upper surface of the lens barrel base plate 34 B and extending in the Z-axis direction (vertical direction) and the plurality of support members 21 support the upper surface so that the upper surface is substantially horizontal. And a second pedestal 32 having a reticle stage base 27. A flat wafer stage base whose upper surface is set to a high degree of flatness through a plurality of second vibration isolation units 41 below the barrel base plate 34B of the first base 34. BS is located above floor F.

The light source used here is a vacuum ultraviolet light having a wavelength of about 120 nm to about 180 nm. Light source emitting light belonging to frequency, for example, the output wavelength 1 5 7 nm of fluorine laser (F ₂ laser) is used. The light source is connected to one end of an illumination system housing 2 constituting an illumination unit ILU via a light transmission optical system (not shown) partially including an optical axis adjustment optical system called a beam matching unit. The illumination system housing 2 actually has a substantially L-shape as a whole extending a predetermined distance toward the far side of the paper of FIG. 1 and extending downward therefrom.

The light source is actually installed in a low-clean service room separate from the clean room where the exposure unit including the illumination unit ILU and the projection optical system PL is installed, or in a utility space under the floor of the clean room. It has been. In addition, other vacuum ultraviolet light sources such as a krypton dimer laser (Kr2 laser) with an output wavelength of 146 nm and an argon dimer laser (Ar2 laser) with an output wavelength of 126 nm are used as the light source. An ArF excimer laser having an output wavelength of 193 nm, a KrF excimer laser having an output wavelength of 248 nm, or the like may be used.

The illumination unit ILU includes an illumination system housing 2 for isolating the interior from the exterior, an illumination uniformity optical system including an optical integrator arranged in a predetermined positional relationship inside the illumination system housing 2, a relay lens, a variable ND filter, a reticle blind, And an illumination optical system including an optical path bending mirror and the like (both not shown). As the optical integrator, a fly-eye lens, a rod integrator (internal reflection type integrator), a diffractive optical element, or the like is used. The lighting unit of the present embodiment has the same configuration as that disclosed in, for example, Japanese Patent Application Laid-Open No. Hei 6-349701 and US Patent Nos. 5,534,970 corresponding thereto. Has become. To the extent permitted by the national laws of the designated country or selected elected country of this international application, the disclosures in the above US patents will be incorporated by reference into this description.

In the lighting unit ILU, a slot on the reticle R on which a circuit pattern, etc. is formed A slit-shaped illumination area (a slit-shaped area elongated in the X-axis direction defined by the reticle blind) is illuminated by the exposure light EL with almost uniform illuminance.

In addition, as shown in FIG. 1, a flat light transmitting window member 20 is provided near the reticle R side end in the illumination system housing 2. The light transmission window member 20 has a function of transmitting the exposure light EL from the illumination unit ILU and maintaining the interior of the illumination system housing 2 in an airtight state. The light-transmitting window member 20 is not limited to a flat plate-shaped member, and any one of the lenses constituting the illumination unit ILU may be air-tightly fixed to the illumination system housing 2 so that the lens can be made to have the above-described light transmission window member. The member 20 may be used instead.

Among the optical members constituting the above-mentioned illumination unit ILU, the material of the member that transmits the exposure light EL such as the lens, the illuminance equalizing optical system, and the light transmission window member 20 is made of a transmittance for vacuum ultraviolet light. It is desirable to use fluorite, for example, which has a high density. However, it is also possible to use a fluorine-doped quartz (a so-called modified quartz) in which a hydroxyl group is excluded to about 10 ppm or less and fluorine is contained at about 1%. Further, not limited to fluorine-doped quartz, it is also possible to use ordinary quartz, quartz having only a small number of hydroxyl groups, and quartz added with hydrogen. Further, fluoride crystals such as magnesium fluoride and lithium fluoride may be used. In order to prevent the air entering from outside during the maintenance of the light transmission optical system and the illumination unit ILU from spreading outside the space to be maintained, a partition is provided at the boundary between the light transmission optical system and the illumination unit ILU. Windows may be provided. In addition, such a partition window may be substituted by an arbitrary optical member installed in the light transmission optical system or the illumination unit ILU, and the light transmission optical system and the illumination unit ILU may be separated into a plurality of airtight spaces. It is good.

The reticle stage RST has a rectangular shape in a plan view (as viewed from above), and floats above a reticle stage base 27 that forms the second frame 32 via a gas static pressure bearing (not shown). Have been. At the center of the reticle stage RST, As can be seen from FIG. 3B, which is an enlarged cross-sectional view near the reticle R in FIG. 1, a rectangular stepped opening 53 is formed in plan view (as viewed from above), and the inner edge of the stepped opening 53 is formed. A plurality of adjacent vacuum suction portions 53a are provided. The reticle R is suction-held by a vacuum suction mechanism (vacuum chuck) (not shown) provided in each of the plurality of vacuum suction sections 53a. On the pattern surface (lower surface) of the reticle R, a rectangular frame-shaped pellicle frame 57 and a pellicle 56 adhered to the lower surface of the pellicle frame 57 are provided. The pellicle 56 prevents dust and the like from adhering to the pattern surface. As shown in Fig. 1, at the two ends of the reticle stage RST in the X-axis direction, movers 25a and 2 of the Y-axis linear motors 24A and 24B as driving devices are respectively provided.

5b is provided. Y-axis linear motor 24 A, 24B stator 26 a, 2

6b is extended at a predetermined length in the Y-axis direction. These stators 26a, 26b are fixed to the floor F separately from the support base BD, and are supported by motor support members 31a, 31b, respectively, which are arranged with the vertical direction as the longitudinal direction. I have. In this case, the movers 25a and 25b are driven in the Y-axis direction by the electromagnetic force generated between the movers 25a and 25b, respectively, so that the reticle stage RST is moved to the reticle stage base. 27 is driven at a predetermined stroke in the Y-axis direction. The reticle stage RST is configured to be capable of minute driving (including rotation) in the XY plane by slightly varying the thrust generated by the Y-axis linear motors 24A and 24B.

In the above description, the stators 26a and 26b of the Y-axis linear motors 24A and 24B are supported above the floor F via the motor support members 31a and 31b, and the vibration generated in the stator is The configuration in which the motor is released to the floor via the motor support members 31a and 31b has been described. However, the present invention is not limited to this. For example, the stators 26a and 26b and the reticle stage base 27 may be levitated and supported on the respective support members via a gas static pressure bearing or the like. In this way, the reticle stay The stators 26a and 26b are driven in accordance with the reaction force at the time of driving the RST, and the momentum of the system including the reticle stage RST and the stator is preserved. Vibration is prevented. In addition, in this case, since the center of gravity does not move, so-called offset load is prevented.

When the stator is connected to the reticle stage base 27, the reticle stage base 27 can be moved relative to the support member in the same manner as described above. Thus, the vibration of the reticle stage base 27 can be effectively suppressed. As a result, it is possible to reduce the influence on the projection optical system P of the reaction force caused by driving the reticle stage R ST in the Y-axis direction.

As shown in FIG. 3A, a reticle Y moving mirror 37 Y consisting of a plane mirror extending in the X-axis direction is fixed to the reticle stage RST at one Y-side end of the upper surface thereof. The measuring beam from the reticle Y interferometer 30 provided on the reticle stage base 27 is irradiated perpendicularly to 37 Y. A reticle X movable mirror 37 X composed of a plane mirror extending in the Y-axis direction is fixed near one X-side end of the upper surface of reticle stage RST, and a reticle (not shown) is attached to movable mirror 37 X. The measurement beam from the X interferometer is irradiated vertically.

These reticle Y interferometer 30 and reticle X interferometer always detect the position of reticle stage RST in the Y-axis direction and X-axis direction with a resolution of, for example, 0.5 to 1 nm. Has become.

In addition, for example, the end surface of reticle stage RST may be mirror-finished to form a reflection surface (corresponding to the reflection surface of the above-described moving mirror). Also, at least one corner cube type mirror (for example, a retro reflector) may be used instead of the movable mirror 37 Y used for detecting the position of the reticle stage RST in the scanning direction (the Y-axis direction in the present embodiment). . Here, one of the reticle Y interferometer 30 and the reticle X interferometer, for example, the reticle Y interferometer 30 is a two-axis interferometer having two measurement axes, and the measured value of the reticle Y interferometer 30 Based on the reticle stage RS In addition to the Y position, rotation in the 0 ° direction can be measured.

The position information (or speed information) of the reticle stage RS measured by the reticle X interferometer and reticle {interferometer 30}, that is, the position information (or speed information) of reticle R is supplied to a controller (not shown). Is done. The controller basically controls the Υ-axis linear motors Α and Β so that the position information (or speed information) output from those reticle interferometers matches the control target value.

Returning to FIG. 1, a first shielding mechanism 101 is provided between the illumination unit ILU and the reticle stage RST, that is, above the reticle stage RSΤ, and the reticle stage RSΤ and the projection optical system PL are connected to each other. , Ie, below the reticle stage RS #, a second shielding mechanism 102 is provided. The configuration and the like of these shielding mechanisms will be described later in detail.

In the projection optical system PL, an optical system including a lens made of a fluoride crystal such as fluorite and lithium fluoride and a reflecting mirror is sealed with a lens barrel 19. Here, as an example of the projection optical system PL, it is assumed that a refraction system with a double-sided telecentricity and a projection magnification j8 of, for example, 14 or 15 is used. Therefore, as described above, when the reticle R is illuminated by the exposure light EL from the illumination unit ILU, the pattern on the reticle R in the illumination area portion is shot on the wafer W by the projection optical system P. A reduced image (partial image) of the pattern portion that is reduced and projected on a part of the region and illuminated with the exposure light EL is formed.

The projection optical system PL is inserted into a circular opening (as viewed from above) formed in the center of the barrel base 34 B with its optical axis direction as the Z-axis direction. It is fixed to the lens barrel base plate 34B via a flange FLG provided slightly below the center of the lens barrel.

The projection optical system PL is not limited to the refractive system, and any of a catadioptric system and a reflective system can be used.

The wafer stage WST is lifted by, for example, a magnetic levitation type or a static pressure of a pressurized gas. A wafer drive system (not shown) as a drive device including a gas floating linear motor or the like is configured to be freely driven in the XY plane along the upper surface of the wafer stage base BS and in a non-contact manner. .

Wafer stage WST is actually freely driven in the XY plane of the (0 including _Z Rotation) is an XY stage which is mounted on the XY stage, and includes a substrate table or the like for holding a wafer W I have. A wafer holder (not shown) is provided on the substrate table, and the wafer W is held by the wafer holder, for example, by vacuum suction. The substrate table is minutely driven in a Z-axis direction and a tilt direction with respect to the XY plane by a drive system (not shown). As described above, the wafer stage WST actually includes a plurality of stages and tables, but in the following, the wafer stage WST is rotated around the X, Y, z, and X axes by the wafer drive system. It is assumed that として is a single stage that can be driven in six degrees of freedom in the directions of 0 y and 0 z, which are rotations around the X and Y axes.

The position information of the wafer stage WST is obtained by a wafer laser interferometer (hereinafter, referred to as a “wafer interferometer”) 20 via a movable mirror 16 provided on the upper surface of the wafer stage WST. It is always measured with resolution.

In practice, the moving mirror is provided with an X moving mirror having a reflecting surface orthogonal to the X axis and a Y moving mirror having a reflecting surface orthogonal to the Y axis. An X laser interferometer for measuring the directional position and a Y laser interferometer for measuring the Y direction position are provided. In FIG. 1, these are representatively shown as a moving mirror 16 and a wafer interferometer 20. I have. Note that, for example, the end surface of wafer stage WST may be mirror-finished to form a reflection surface (corresponding to the reflection surface of movable mirror 16). In addition, the X laser interferometer and the Y laser interferometer are multi-axis interferometers having a plurality of measurement axes, and in addition to the X and Y positions of the wafer stage WST, the rotation (the rotation around the Z axis). 0 z rotation), pitching (0 X rotation which is rotation around the X axis), rolling (Y The rotation around the axis (0 y rotation)) can also be measured. Therefore, in the following description, it is assumed that the laser interferometer 26 measures the position of the wafer stage WST in the directions of five degrees of freedom of X, Y, 0z, 0y, and θχ. In addition, the multi-axis interferometer irradiates a laser beam onto a reflection surface installed on a gantry (not shown) on which the projection optical system PL is mounted via a reflection surface installed on the wafer stage WST at an angle of 45 °. Alternatively, relative position information about the optical axis direction (Z-axis direction) of the projection optical system PL may be detected.

The position information (or speed information) of the wafer stage WST from the wafer interferometer 20 described above is sent to a control device (not shown), and the control device performs processing based on the position information (or speed information) of the wafer stage WS. The wafer stage WST is driven via the drive system.

A third shielding mechanism 103 is provided between the wafer stage WST and the projection optical system PL. The configuration and the like of the third shielding mechanism 103 will be described later in detail. The control system is mainly configured by a control device (not shown). The control device includes a so-called microcomputer (or workstation) including a CPU (central processing unit), a ROM (read only memory), a RAM (random-access memory), and the like. In addition to performing the operation, for example, synchronous scanning of the reticle R and the wafer W, stepping of the wafer, and the like are controlled so that the exposure operation is properly performed.

Specifically, for example, at the time of scanning exposure, the control device controls the wafer in synchronization with the reticle R being scanned at a speed V _R = V in the + Y direction (or one Y direction) via the reticle stage RST. Through the stage WST, the wafer W is scanned in one Y direction (or + Y direction) with respect to the exposure area at a speed V _w = j8 V (j8 is the projection magnification from the reticle R to the wafer W). , Reticle interferometer, and wafer interferometer 20 to control the position and speed of reticle stage RST and wafer stage WS Y via Y-axis linear motors 24A and 24B and wafer drive system, respectively I do.

Further, at the time of stepping, the control device controls the position of the wafer stage WST via the wafer drive system based on the measurement values of the reticle interferometer and the wafer interferometer 20.

By the way, when light having a wavelength in the vacuum ultraviolet region is used as exposure light, a gas having a strong absorption characteristic for light in such a wavelength band, such as oxygen, water vapor, or a hydrocarbon-based gas (hereinafter, referred to as “light”). (Referred to as “absorptive gas” as appropriate). For this reason, in the present embodiment, a device is devised to eliminate as much as possible the absorbent gas in the entire space on the optical path from the light source to the wafer W. This will be described in detail later.

Next, the above-described first to third shielding mechanisms (101, 102, 103) will be described.

As shown in FIGS. 1 and 3A, the first shielding mechanism 101 is configured such that one surface (the lower surface in FIG. 1) having an XY cross section provided above the reticle R and having a rectangular frame shape is entirely formed. An illumination system side gas purge skirt 22 as a shielding member composed of a rectangular parallelepiped member having a small thickness as a whole and having an opening at the center of the other surface (the upper surface in FIG. 1). ing. The illumination system side gas purge skirt 22 is arranged between a specific object, which is one of a reticle R and a reticle stage RST holding the reticle R, and the illumination unit ILU, and is provided at least between the specific object and the specific unit. With the above clearance formed, the space including at least the area corresponding to the pattern area of the reticle R on the illumination unit ILU side of the reticle R is shielded from the outside air.

The illumination system side gas purge skirt 22 has an upper end surface 22 a fixed to a reticle side end (lower end) of the illumination system housing 2 of the illumination unit ILU, and a lower end surface 22 b formed on the upper surface of the reticle stage RST. (Lighting unit ILU side surface). That is, gas purges on the lighting system side A predetermined clearance is formed between the lower end surface 22b of the cart 22 and the upper surface of the reticle stage RST. In this case, a substantially airtight space IM is formed between the illumination system side gas purge skirt 22, the illumination unit ILU, and the reticle stage RST.

In this space IM, in order to ensure high airtightness, the narrower the clearance is, the better. However, the reticle stage RST may generate vertical vibrations due to scanning, so in order to avoid contact between the reticle stage RST and the gas purge scar 22 on the illumination system side even when vertical vibrations occur. It is necessary to provide a certain interval. The interval varies depending on the configuration of each mechanism, but from the viewpoint of airtightness, the above clearance is preferably at most 3 mm or less.

A drive mechanism is provided between the illumination-system-side gas purge skirt 22 and the reticle stage RST. By driving the lever to expand and contract and tilt by the driving mechanism, the clearance can be adjusted so as to be substantially uniform over the entire circumference of the illumination system side gas purge skirt 22.

FIG. 4 shows a plan view of the reticle stage RST. As shown in FIG. 4, the illumination system side gas purge skirt 22 has a rectangular frame shape long in the Y-axis direction. The reason why the illumination system side gas purge skirt 22 is set long in the Y-axis direction is as follows. That is, in the present embodiment, the reticle R (reticle stage RST) is scanned (scanned) in the Y-axis direction. However, to prevent contamination of the reticle R, the reticle stage RST is set to Y Even when scanning is performed in the axial direction, the stepped opening 53 accommodating the reticle R must always be accommodated in the illumination system side gas purge scar 22. On the other hand, if the length in the Y-axis direction (length SY shown in Fig. 4) is not sufficient, As a result, the reticle R and the stepped opening 53 may protrude from the illumination-side gas purge skirt 22. A large gap is created, and the airtightness of the space IM cannot be maintained. However, since the space IM is a space on the optical path from the light source to the wafer W, it is necessary to secure a certain degree of airtightness in order to efficiently perform gas purging described later. It is necessary to prevent such a situation from occurring.

The length SY is, specifically, the length of the pattern area of the reticle R in the Y-axis direction, the length of the illumination area for illuminating the reticle R in the Y-axis direction (a so-called slit width), and the approach accompanying scanning. The sum of the distance (the sum of the pre-scan distance and the overscan distance that the reticle stage RST moves in the acceleration area and deceleration area before and after the synchronous movement in which the exposure is performed, ie, the so-called pre-scan distance and over-scan distance) is added. Specifically, when the reticle R is a 6-inch square (15 Omm square) size, the Y-axis length SY inside the illumination system side gas purge skirt 22 should be about 250 mm or more. There is a need.

On the other hand, regarding the length SX in the X-axis direction of the gas purge skirt 22 on the illumination system side, since the reticle stage RST is not driven in the X-axis direction as much as the Y-axis direction, the size of the reticle R (or the stepped opening 53) is large. It is sufficient to provide some margin in the space. For example, if the reticle R is 6 inches square (15 Omm square), the length SX should be set to about 18 Omm or more.

In order to ensure the airtightness of the space IM, it is necessary that the reticle stage RST be large enough to keep the illumination system side gas purge skirt 22 covered even if the reticle stage RST scans in the Y-axis direction. Becomes For this reason, the total length of the reticle stage RST in the Y-axis direction (length RYi shown in FIG. 4) is the length SY in the Y-axis direction inside the illumination system side gas purge cartridge 22 and the side wall of the illumination system side gas purge skirt 22. Of the reticle stage R ST in the Y direction Of the reticle stage RST, the total length in the Y-axis direction R Yi of the reticle stage RST must be equal to or greater than the total length of the reticle stage RST. Must be at least 60 Omm.

Also, in order to avoid contact between the reticle stage RST and the illumination system side gas purge skirt 22 due to the scanning of the reticle stage RST, the surface shape of the reticle stage RST needs to be flat at least in the Y-axis direction. is there. When this condition is expressed by a mathematical expression, it is necessary that the function Z = f (Y) with respect to the position of the Z position on the surface of the reticle stage RST in the Y direction is constant with respect to Y.

On the other hand, the surface shape of the reticle stage RST is not necessarily required to be flat in the X-axis direction, and may have a step or a curve. In such a case, the gas purge force on the illumination system side is required. It is necessary to machine the lower end surface 22b of the reticle stage RS into almost the same shape as the surface shape of the reticle stage RS, which is very complicated from the viewpoint of workability. Therefore, it is desirable that the surface shape of reticle stage RST in the X-axis direction is also flat.

In this case, in such a structure, all the members included in the space IM, for example, the reticle R and other members arranged around the reticle do not protrude above the upper surface of the reticle stage RST. (See Fig. 3B).

The first shielding mechanism 101 has, in addition to the above-described illumination system side gas purge skirt 22, a piping system and a differential exhaust mechanism for efficiently performing gas replacement in the space IM. Will be described later in detail.

As shown in FIG. 1, the second shielding mechanism 102 was held below the reticle stage RST via a plurality of barge-square holding mechanisms 29 provided on a barrel base 34B. A projection system side gas purge skirt 28 as a shielding member is provided. The upper end surface 28a of the gas purge skirt 28 on the projection system side is close to the lower surface of the reticle stage RST (the surface on the projection optical system PL side) without contact. The lower end surface 28 b is disposed in close proximity to the upper end surface of the barrel 19 of the projection optical system PL without touching it. That is, between the upper end surface 28 a of the projection system side gas purge port 28 and the lower surface of the reticle stage RST, and between the lower end surface 28 b of the projection system side gas purge skirt 28 and the projection optical system PL. Clearance is formed respectively.

In this case, the projection system side gas purge skirt 28, the reticle stage RST, the reticle R, and the projection optical system PL form a substantially airtight space MP.

Here, as with the clearance between the illumination unit ILU and the reticle stage RST, it is preferable that the clearance is as narrow as possible.However, vertical oscillations occur due to the movement of the reticle stage RST in the scanning direction. In this case, it is necessary to avoid contact between the reticle stage RST and the gas purge skirt 28 on the projection system side. In this case, the clearance is preferably set to 3 mm or less in the same manner as described above. Also in this case, a bellows and a drive mechanism for extending and contracting and tilting the bellows are provided at the upper end of the projection system side gas purge skirt 28, and the upper end surface 28a of the projection system side gas purge skirt 28 is provided. The clearance may be set uniformly over the entire circumference.

The shape and size of the upper end of the gas purge skirt 28 on the projection system side are the same as the lower end of the gas purge skirt 22 on the illumination system side (that is, the inside has a length in the Y-axis direction S 丫 and a length in the X-axis direction SX). (Plan view rectangular frame). The reason for adopting such a shape and size is the same as in the case of the gas purge skirt 22 on the illumination system side, so that the description thereof will be omitted.

Note that, in this case, the pellicle 56 and all other structures around the reticle are controlled so that the reticle stage RST and the reticle R do not contact the projection system side gas purge skirt 28 as the reticle stage RST is driven. Reticle stay It is necessary to adopt a configuration that does not protrude below the RST (see Figure 3B).

On the other hand, the shape of the lower end face 28 b of the projection system side gas purge skirt 28 is a circular frame. This is because the lens barrel 19 of the projection optical system PL has a cylindrical shape, and the shape of the upper end surface is a circular frame. Therefore, from the viewpoint of the airtightness of the space MP, the projection system side gas purge skirt 28 This is because it is preferable that the lower end surface 28 b has the same shape as the upper end surface of the lens barrel 19 of the projection optical system PL.

Since the projection optical system PL is fixed to the first frame 34, the projection system side gas purge skirt 28 and the projection optical system PL are air-tightly joined (fixed) via a sealing member such as an O-ring. It is also possible to do However, if the projection system side gas purge force 28 vibrates due to driving of the reticle stage RST, etc., and the vibration is transmitted to the projection optical system PL, there is a possibility that the imaging characteristics may be degraded. However, as in the present embodiment, it is preferable to provide a predetermined interval (clearance) and arrange them close to each other. This clearance is also preferably set to 3 mm or less as before.

By the way, in the exposure apparatus 100, the reticle R needs to be replaced with another reticle as appropriate, so that the reticle R can be replaced while maintaining the airtightness of the space IM and the space MP. It is necessary to adopt a reticle exchange mechanism. To achieve this, for example, a reticle transport window (not shown) that can be opened and closed is provided on a part of the side wall of the gas purge skirt 22 on the illumination system side, and a reticle loader (not shown) is provided through the reticle transport window. Reticle R can be carried out of space IM and a new reticle can be carried into space IM to replace the reticle, or the reticle stage can be moved in the Y-axis direction of RS reticle. Even if the entire reticle R moves outside the illumination system side gas purge skirt 22 and projection system side gas purge skirt 28 in the Y-axis direction, the illumination system side gas purge skirt 22 and projection system side gas purge Force 2 8 reticle stage RST The reticle provided outside the illumination system side gas purge skirt 22 with the entire reticle R coming out of the illumination system side gas purge skirt 22 and the projection system side gas purge skirt 28 It is also possible to adopt a configuration in which reticle exchange is performed using a loader.

In this case, if the moving direction of the reticle stage RST at the time of reticle replacement is set to the —Y direction, the illumination system-side gas purge cartridge 22 and the projection system-side gas purge cartridge 2 are used even when the reticle is replaced. So that the airtightness between the reticle stage RST and the reticle stage RST is maintained (that is, even if the entire reticle R comes out of the illumination system side gas purge skirt 22 and the projection system side gas purge skirt 28), the reticle stage Make sure that the + Y side end of the RST does not exceed the + Y side wall of the illumination system side gas purge skirt 22 and the projection system side gas purge skirt 28), and the length of the reticle stage RST in the Y axis direction (specifically, It is necessary to set the length RY ₂ ) of the + Y side sufficiently longer than the reticle R shown in FIG.

By the way, as shown in FIG. 2, the illumination system side gas purge skirt 22 includes a first air supply pipe 60, a first exhaust pipe 61, a second air supply pipe 72, and a second exhaust pipe 73-4. Different types of piping are connected.

FIG. 5A is a cross-sectional view of a portion where the lower end surface 2 2 b of the illumination system side gas package skirt 22 and the reticle stage RST are disposed in close proximity, and FIG. 5B shows the illumination system side. A part of the surface (lower end surface 22b) of the gas purge skirt 22 near the reticle stage RST is shown in an enlarged manner. FIG. 5A corresponds to a cross section taken along line AA of FIG. 5B.

As shown in FIG. 5A, the first air supply pipe 60 has a through-hole mosquito as a supply opening formed from the outside to the inside of the side wall of the illumination-system-side gas purge plate 22. 1 is connected from the outside of the illumination system side gas purge skirt 22 via a connector 75. An air supply nozzle 76 is provided on the opposite side of the through hole 2 51 from the first air supply pipe 60. Although not shown, the first exhaust pipe 61 is, like the first air supply pipe 60, an exhaust gas (not shown) formed to communicate from the outside to the inside of the side wall of the illumination system side gas purge skirt 22. The illumination system side gas purge skirt 22 is connected to the through hole as an opening through the connector via a connector.

In an exposure apparatus using an exposure wavelength in the vacuum ultraviolet region as in the present embodiment, the gas in the space IM is replaced with a low-absorbing gas in order to avoid the absorption of exposure light by an absorbing gas such as oxygen or water vapor. There is a need to. For this reason, in the present embodiment, the first gas supply pipe 60 and the first exhaust pipe 61 are used to pass the space IM inside the space IM with a specific gas having a characteristic of little absorption of light in the vacuum ultraviolet region, for example, nitrogen, and helium, It is filled with a rare gas such as argon, neon, or krypton, or a mixed gas thereof (hereinafter referred to as “low-absorbing gas J” as appropriate).

That is, as shown in FIG. 2, the other end of the first air supply pipe 60 is connected to one end of a gas supply device 50, and the other end of the first exhaust pipe 61 is connected to a gas recovery device (not shown). It is connected. The first air supply pipe 60 and the first exhaust pipe 61 are provided with an air supply valve and an exhaust valve (not shown), respectively, and a control device (not shown) opens and closes the air supply valve and the exhaust valve, and By appropriately controlling the operation and stop of the pump incorporated in the gas supply device 50, the space IM is filled with a low-absorbing gas, and the concentration of the absorbing gas in the interior IM is reduced to several ppm or less. I have. Note that the low-absorbent gas may always flow in the space IM.

As shown in FIG. 5A, one end of the second air supply pipe 72 is connected to an air supply pipe 16 having an L-shaped cross section formed inside the side wall of the gas purge skirt 22 on the lighting system side. Connected through 5. The other end of the air supply line 16 7 to which one end of the second air supply pipe 7 2 is connected is used for air supply as an air supply port formed on the lower end surface 2 2 b of the illumination system side gas purge skirt 22. It is in a state of communicating with the annular groove 67. In this case, the width of the air supply annular groove 67 is set to, for example, about 1 to 3 mm, and the depth is set to, for example, about 1 to 3 mm. In addition, one end of the second exhaust pipe 73 is connected via a connector 66 to an exhaust pipe 16 having an L-shaped cross section formed inside the side wall of the illumination system side gas purge skirt 22. ing. The exhaust pipe line 168 to which one end of the second exhaust pipe 73 is connected is provided with the annular groove for air supply 6 7 with respect to the space IM of the lower end face 22 b of the illumination-side gas purge skirt 22. It is in a state where it communicates with an annular exhaust groove 68 as an exhaust port formed on the outside of the container. In this case, the width of the exhaust annular groove 68 is set to, for example, about 1 to 3 mm, and the depth thereof is set to, for example, about 1 to 3 mm, similarly to the annular groove for air supply 67. The interval between the annular grooves 67 and 68 can be set to about 5 to 20 mm. From the viewpoint of ensuring airtightness, it is preferable to set the interval as wide as possible in accordance with the thickness of the side wall of the illumination system side gas purge scar 22.

Here, as shown in FIG. 2, the other end of the second supply pipe 72 is connected to a low-absorbent gas supply device 80, and the other end of the second exhaust pipe 73 is connected to a vacuum pump 79. It is connected to the. Then, a control device (not shown) appropriately controls the operation and stop of the pump and the vacuum pump 79 built in the supply device 80, as shown in FIG. The low-absorbing gas (pressurized gas) supplied via the air supply line 2 and the supply line 16 7 flows from the annular groove 6 7 to the lower end surface 2 2 b of the illumination system side gas purge skirt 2 2 and the upper surface of the reticle stage RST. The gas inside the clearance D 1 is exhausted to the outside via the annular four groove 68, the exhaust pipe line 168, and the second exhaust pipe 73. That is, the gas flow including the second air supply pipe 72 and the second exhaust pipe 73 mainly flows from the second air supply pipe 72 to the air supply pipe line 16 7 → the annular groove for air supply 6 7 → the clearance D 1 —Exhaust annular groove 6 8—Exhaust pipe line 1 68 → Second exhaust pipe 73, with clearance D1 extending from the inside (ie, space IM side) of illumination system side gas purge scart 22 An oncoming gas flow is formed. Thus, the inflow of oxygen and water vapor from the outside to the inside (space IM) of the gas purge skirt 22 on the lighting system side is blocked by the flow of the gas. This is extremely effective in improving the purge performance in the space IM (ie, the ability to reduce the oxygen and water vapor concentrations).

In this case, a part of the low-absorbent gas supplied from the supply groove 65 enters the space IM via the clearance D1. In addition, since the gas in the clearance D1 is exhausted to the outside through the exhaust annular groove 68, even if a part of the gas outside the illumination system side gas purge skirt 22 enters the clearance D1. However, this gas is exhausted to the outside through the exhaust annular groove 68.

Actually, a plurality of (for example, three) supply and exhaust pipes are formed in the annular grooves 67 and 68, and the second supply pipe and the second exhaust pipe are formed in these pipes. The pipes are connected to each other, but in Fig. 2 etc., for convenience of explanation and illustration, it is assumed that the second air supply pipe and the second exhaust pipe are connected to the illumination system side gas purge skirt 22 respectively. Is shown.

Note that the annular groove is not limited to the case where two grooves are formed as described above, and it is also possible to form a quadruple or six-fold groove by further combining a plurality of two grooves.

The gas supplied to the clearance via the second air supply pipe 72 is not limited to the low-absorbing gas described above. For example, the gas exhausted from the clearance is larger than the gas supplied to the clearance, and the gas is supplied to the clearance. If the gas supplied from the annular groove 67 does not enter the space IM, a gas other than the low-absorbent gas such as pressurized air may be used.

As shown in FIG. 2, the projection system side gas purge skirt 28 includes a first air supply pipe 77, a first exhaust pipe 78, a second air supply pipe 81, 83, and a second exhaust pipe 82. , 84 are respectively connected.

FIG. 6A is a cross-sectional view showing a portion where the upper end surface 28 a of the projection system side gas purge cartridge 28 and the reticle stage RST are arranged in close proximity, and FIG. The gas purge cartridge 28 and the lens barrel 19 of the projection optical system PL are placed close to each other. The cross section is shown in the cross section.

As shown in FIG. 6A, the first air supply pipe 77 has a through hole 25 as a supply opening formed in the side wall of the projection system side gas purge plate 28 so as to communicate from the outside to the inside. Is connected from the outside of the projection system side gas purge skirt 28 via a connector 86. An air supply nozzle 87 is provided on the opposite side of the through hole 252 from the first air supply pipe 77.

Although not shown, the first exhaust pipe 78 has a through hole formed in the side wall of the projection system side gas purge skirt 28 from the outside to the inside, similarly to the first air supply pipe 77. The connection is made from the outside of the projection system side gas purge skirt 28 via a connector.

In the exposure apparatus that uses the exposure wavelength in the vacuum ultraviolet region as in this embodiment, the gas in the space MP is also replaced with a low-absorbing gas in order to avoid absorption of the exposure light by an absorbing gas such as oxygen and water vapor. There is a need to. For this reason, in the present embodiment, the space MP is filled with the low-absorbent gas by using the first air supply pipe 77 and the first exhaust pipe 78.

That is, as shown in FIG. 2, the other end of the first air supply pipe 77 is connected to a gas supply device 50, and the other end of the first exhaust pipe 78 is connected to a gas recovery device (not shown). Have been. The first air supply pipe 77 and the first exhaust pipe 78 are provided with an air supply valve and an exhaust valve (not shown), respectively, and a control device (not shown) opens and closes the air supply valve and the exhaust valve, and By appropriately controlling the operation and stop of the pump built in the gas supply device 50, the space MP is filled with a low-absorbing gas, and the concentration of the absorbing gas in the space MP becomes several ppm or less. ing. It should be noted that a low-absorbent gas may always flow in the space MP.

As shown in FIG. 6A, one end of the second air supply pipe 8 1 is connected to an air supply pipe 16 9 having an L-shaped cross section formed inside the side wall of the projection system side gas purge skirt 28. Connected via 8. One end of this second air supply pipe 81 is connected The supplied air supply channel 169 is in communication with an air supply annular H groove 170 as an air supply port formed on the upper end surface 28 a of the projection system side gas purge skirt 28. In this case, the annular groove 170 for air supply is set to have a width of, for example, about 1 to 3 mm and a depth of, for example, about 1 to 3 mm.

In addition, one end of the second exhaust pipe 82 is connected via a connector 89 to an exhaust pipe 17 having an L-shaped cross section formed inside the side wall of the gas purge skirt 28 on the projection system side. ing. The exhaust pipe line 171, to which one end of the second exhaust pipe 82 is connected, has an annular groove for air supply 170 with respect to the space MP of the upper end surface 28a of the projection system side gas purge skirt 28. It is in a state where it communicates with an exhaust annular concave groove 112 serving as an exhaust port formed outside of the air conditioner. In this case, as in the case of the air supply annular groove 170, the width of the exhaust annular groove 172 is set to, for example, about 1 to 3 mm, and the depth thereof is set to, for example, about 1 to 3 mm. ing. The interval between the annular concave grooves 170 and 172 can be set to about 5 to 2 Omm. From the viewpoint of ensuring airtightness, it is preferable to set the interval as wide as possible in accordance with the thickness of the side wall of the projection system side gas purge skirt 28.

Here, the other end of the second air supply pipe 81 is connected to the aforementioned supply device 80 as shown in FIG. 2, and the other end of the second exhaust pipe 82 is connected to the vacuum pump 79. ing. A control device (not shown) controls the operation and stop of the pump and the vacuum pump 79 incorporated in the supply device 80 as appropriate, as shown in FIG. And the pressurized gas supplied via the air supply line 169 flows from the annular groove 170 to the clearance between the upper end surface 28 a of the projection system side gas purge cartridge 28 and the lower surface of the reticle stage RST. The gas is supplied to D2, and the gas inside the clearance D2 is exhausted to the outside via the annular groove 172, the exhaust pipe 171, and the second exhaust pipe 82. That is, the flow of the gas including the second air supply pipe 81 and the second exhaust pipe 82 mainly depends on the second air supply pipe 81 → the air supply line 169 ~ the annular groove for air supply 170 → the clearance D 2 → Exhaust annular groove 1 7 2 → Exhaust line 1 7 1 → Second exhaust line 8 2 In the clearance D2, a gas flow is formed from the inside of the projection system side gas purge skirt 28 (that is, the space MP side) to the outside. In this case, a part of the low-absorbent gas supplied from the annular groove 170 for air supply enters the space MP via the clearance D2. Also, since the gas in the clearance D 2 is exhausted to the outside through the exhaust annular groove 17 2, part of the gas outside the projection system side gas purge scar 28 enters the clearance D 2. However, this gas is exhausted to the outside via the exhaust annular groove 172.

As shown in FIG. 6B, one end of the second air supply pipe 83 is connected to an air supply pipe 17 3 having an L-shaped cross section formed inside the side wall of the projection system side gas purge skirt 28. Connected via 0. An air supply pipe line 17 3 to which one end of the second air supply pipe 83 is connected is provided with an air supply annular concave groove 1 as an air supply port formed on the lower end surface 28 b of the projection system side gas purge skirt 28. It is in a state of communication with 74. In this case, the width of the annular groove for air supply 174 is set to, for example, about 1 to 3 mm, and the depth thereof is set to, for example, about 1 to 3 mm.

Further, one end of the second exhaust pipe 84 is connected via a connector 91 to an exhaust pipe 175 having an L-shaped cross section formed inside the side wall of the gas purge skirt 28 on the projection system side. ing. The exhaust pipe line 17 5 to which one end of the second exhaust pipe 84 is connected is provided with an annular groove for air supply 1 f 4 in the space MP of the lower end surface 28 b of the projection system side gas purge skirt 28. It is in a state of communicating with an exhaust circular concave groove 176 as an exhaust port formed on the outside. In this case, the annular groove for exhaust 176 is set to have a width of, for example, about 1 to 3 mm and a depth of, for example, about 1 to 3 mm, similarly to the annular groove for air supply 174. ing. Further, the interval between the annular H-grooves 174 and 176 can be set to about 5 to 2 Omm. In addition, from the viewpoint of airtightness, it is preferable to set the interval as wide as possible in accordance with the thickness of the side wall of the projection system side gas purge skirt 28 as in the above.

Here, as shown in FIG. 2, the other end of the second air supply pipe 83 is connected to the aforementioned supply device. The other end of the second exhaust pipe 84 is connected to a vacuum pump 79. Then, a control device (not shown) controls the operation and stop of the pump and vacuum pump 79 built in the supply device 80 as appropriate, as shown in FIG. And the pressurized gas supplied through the air supply line 1 7 3

From 7 4, gas is supplied to the clearance D 3 between the lower end surface 28 b of the projection system-side gas purge unit 28 and the lower surface of the reticle stage RST, and the gas inside the clearance D 3 is formed into an annular groove 1 7 6 The air is exhausted to the outside via the exhaust pipe 17 5 and the second exhaust pipe 84. That is, the flow of the gas including the second air supply pipe 83 and the second exhaust pipe 84 mainly depends on the second air supply pipe 83 → the air supply pipe 1 73 → the annular groove for air supply 1 74 → the clearance. D 3 → Exhaust annular groove 1 7 6 → Exhaust line 1 7 5—Second exhaust pipe 84 4 Inside the clearance D 3, the inside of the projection system side gas purge skirt 28 (that is, A gas flow from the space (MP side) to the outside is formed. Thus, the upper end surface 28 a and the lower end surface 2

8b, the gas flow from the outside to the inside of the space MP is formed, so that the inflow of oxygen and water vapor outside the projection system side gas purge skirt 28 into the space MP can be blocked. It is extremely effective in improving the purge performance in the space MP (that is, the performance of reducing oxygen concentration and water vapor concentration).

In this case, a part of the low-absorbent gas supplied from the annular groove for air supply 174 enters the space MP via the clearance D3. In addition, since the gas in the clearance D3 is exhausted to the outside through the annular groove for exhaust 176, a part of the gas outside the projection system side gas purge skirt 28 enters the clearance D3. However, this gas is exhausted to the outside via the exhaust annular groove 176.

Actually, a plurality of (for example, three) supply and exhaust pipes are formed in each of the annular concave grooves 170, 172, 174, 176 in a communicating state. The second air supply pipe and the second exhaust pipe are connected to these conduits, respectively.However, in FIG. 2 and the like, for convenience of explanation and illustration, the second air supply pipe and the second exhaust pipe are Carts 2 and 2 are shown as being connected two each.

It should be noted that if the type of purge gas in the barrel 19 of the projection optical system PL is different from the type of purge gas in the space MP, the upper end of the projection optical system PL (closer to the reticle R) The holding mechanism H1 of the lens L1 shown in Fig. 6B located on the side must have sufficient airtightness to prevent both gases from entering.

As shown in FIG. 1, the third shielding mechanism 103 is disposed between the projection optical system PL and the wafer W on the wafer stage WST, and is disposed on the lower surface of the lens barrel base 34 B. It is configured to include a wafer gas purge skirt 36 as a shielding member suspended and supported by a plurality of suspension support members 92 whose ends are fixed. The upper end surface 36 a of the wafer gas purge skirt 36 is disposed in close proximity without contacting the lower end surface of the lens barrel 19 of the projection optical system PL, and the lower end surface 36 b of the wafer gas purge skirt 36 is also placed on the wafer. It is arranged close without contacting W. As can be seen from FIG. 1, the gas purge skirt 36 has a substantially columnar shape, and a truncated cone-shaped hollow portion 36c communicates from the upper end surface to the lower end surface at the center. Therefore, a substantially airtight space PW is formed between the wafer gas purge skirt 36, the projection optical system P, and the wafer W.

FIG. 7A shows a cross-sectional view of the vicinity of the wafer gas purge skirt 36, and FIG. 7B shows a view of the wafer gas purge skirt 36 viewed from above (+ Z side). Note that the figure on the left half of the center line in FIG. 7A (the optical axis AX of the projection optical system PL) corresponds to the cross-sectional view taken along the line BB of FIG. 7B, and the right half of the center line in FIG. The drawing in FIG. 7 corresponds to a cross-sectional view taken along the line CC in FIG. 7B.

In the space PW, in order to ensure airtightness, the projection optical system PL barrel 19 (Clearance) D4 between the wafer gas skirt 36 and the wafer gas skirt 36 and the clearance D5 between the wafer gas skirt 36 and the wafer W are preferably as small as possible. However, with regard to the clearance D5 between the wafer gas purge skirt 36 and the wafer W, the wafer stage WST may generate vertical vibration due to movement in the scanning direction and the non-scanning direction orthogonal thereto. Therefore, it is necessary to keep a certain distance between the wafer W and the wafer gas purge skirt 36 in order to avoid contact between the wafer W and the wafer gas purge skirt 36 even when vertical vibration occurs. Although the interval varies depending on the configuration of each mechanism, the clearance D5 is preferably at most 3 mm from the viewpoint of airtightness.

It is also possible to provide a bellows at the lower end of the wafer gas purge skirt 36 and a drive mechanism for expanding and contracting and tilting the bellows so that the clearance D5 can be adjusted uniformly over the entire circumference. is there.

As shown in FIG. 2, the first gas supply pipe 1 1 1, the first gas exhaust pipe 1 1 2, the second gas supply pipe 1 1 3, and the second gas exhaust pipe 1 1 4 are connected to the wafer gas purge skirt 36. Has been done. Here, actually, as shown in FIGS. 7A and 7B, three second air supply pipes 113 are provided for the wafer gas purge skirt 36 (second air supply pipes 113 A to 113 P). C) are connected, and three second exhaust pipes 114 are connected to the wafer gas purge skirt 36 (second exhaust pipes 114 A to 114 C). For convenience of illustration, only one of each is shown.

As shown in FIGS. 7A and 7B, the first air supply pipe 1 1 1 has a through hole 2 5 as an air supply opening formed from the outside to the inside of the wafer gas skirt 36. 3 is connected from the outside of the wafer gas purge skirt 36 via a connector. An air supply nozzle 115 is provided on the opposite side of the through-hole 253 from the first air supply pipe 111.

The first exhaust pipe 1 1 2 is disposed at a position substantially symmetrical to the first air supply pipe 1 1 1 with the wafer gas purge skirt 36 interposed therebetween, and is located outside the wafer gas purge skirt 36. The through hole 254 formed in communication with the inside from the outside is connected from outside the wafer gas purge skirt 36 via a connector.

In the exposure apparatus using the exposure wavelength in the vacuum ultraviolet region as in the present embodiment, the gas in the space PW is also replaced with a low absorption gas in order to avoid the absorption of the exposure light by the absorption gas such as oxygen and water vapor. There is a need to. For this reason, in the present embodiment, the space PW is filled with the low-absorbent gas by using the first air supply pipe 111 and the first exhaust pipe 112.

That is, as shown in FIG. 2, the other end of the first air supply pipe 111 is connected to one end of a gas supply device 50, and the other end of the first exhaust pipe 112 is a gas not shown. Connected to collection device. The first air supply pipe 1 1 1 and the first exhaust pipe 1 1 2 are provided with an air supply valve and an exhaust valve (not shown), respectively, and a control device (not shown) opens and closes the air supply and exhaust valves. The space PW is filled with a low-absorbent gas by appropriately controlling the operation and stop of the pump incorporated in the gas supply device 50, and the concentration of the absorptive gas in the space PW is several ppm or less. It has become. It should be noted that the low-absorbent gas may always flow in the space PW.

7A and 7B, the second air supply pipes 113A to 113C are substantially c-shaped and formed at substantially equal intervals in the wafer gas purge skirt 36. The two air supply lines 123 A to 123 C are connected via connectors from outside the wafer gas purge skirt 36. Each of the second air supply pipes 1 2 3 A to 1 2 3 C is provided with an annular groove for air supply as an air supply port formed on the upper end surface 36 a of the wafer gas purges force 36. In this state, the gas supply skirt 36 communicates with the gas supply annular groove 1 19 as a gas supply port formed in the lower end surface 36 b of the wafer gas purge skirt 36.

Further, the second exhaust pipes 114A to 114C are substantially T-shaped formed in the vicinity of the second air supply pipes 123A to 123C in the wafer gas purge skirt 36. Second exhaust line 1 2 4 A to 1 2 4 C Are connected via a connector. Each of the second exhaust pipes 124A to 124C is for exhaust formed outside the air supply annular groove 117 with respect to the space PW of the upper end surface 36a of the wafer gas purge skirt 36. The annular concave groove 1 18 and the exhaust annular concave groove 1 20 as an exhaust port formed outside the air supply annular groove 1 19 with respect to the space PW of the lower end surface 36 b of the wafer gas purge skirt 36. It is in a state of communication with.

In this case, each of the air supply annular groove 1 17, 1 19 and the exhaust annular groove 1 18, 120 has a width of, for example, about 1 to 3 mm and a depth of, for example, 1 to 3. It is set to about mm. The interval between the annular grooves 1 17 and 1 18 and the interval between the annular grooves 1 19 and 1 20 can both be set to about 5 to 2 Omm. From the viewpoint of ensuring airtightness, it is preferable to set the interval as wide as possible in accordance with the thickness of the side wall of the wafer gas purge skirt 36. Here, as shown in FIG. 2, the second air supply pipes 113A to 113C (hereinafter, also appropriately referred to as "second air supply pipes 113") are connected to the wafer gas purge skirt 36 and the supply device 80, respectively. The second exhaust pipes 114A to 114C (hereinafter, also appropriately referred to as "second exhaust pipe 114") connect the wafer gas purge skirt 36 and the vacuum pump 79. Then, the control device (not shown) controls the operation and stop of the pump and the vacuum pump 79 built in the supply device 80 as appropriate, thereby connecting the second air supply pipe 113 and the air supply pipe 123 as described above. The pressurized gas supplied via the annular concave grooves 1 17 and 1 19 respectively provides a clearance D 4 between the upper end surface 36 a of the wafer gas purge skirt 36 and the lower surface of the projection optical system PL, and a wafer gas purge scan. The gas in the clearances D 4 and D 5 is supplied to the clearances D 4 and D 5, respectively, and is supplied to the clearances D 5 and D 5 between the lower end surface 36 b of the wafer 36 and the wafer W. The air is exhausted to the outside via the second exhaust pipe 114 in sequence. That is, the flow of the gas including the second air supply pipe 113 and the second exhaust pipe 114 is mainly the second air supply pipe 113 → the air supply line 123A to 123C → the annular groove for air supply. 1 1 7 (Also 1 1 9) —Clearance D 4 (or D5) → Circumferential groove for exhaust 1 1 8 (or 1 20) —Exhaust line 1 24A to 1 24〇 → Second exhaust pipe 1 14 and clearance D4 , D5, a gas flow from the inside of the wafer gas purge skirt 36 (that is, the space PW side) to the outside is formed.

As described above, since the gas flows from the inside to the outside of the space PW at both the upper end surface 36a and the lower end surface 36b of the wafer gas purge skirt 36, the outside of the wafer gas purge skirt 36 with respect to the space PW is formed. The flow of oxygen and water vapor can be blocked, and this is extremely effective in improving the purging performance (ie, the performance of reducing the oxygen concentration and water vapor concentration) in the space PW.

In this case, a part of the low-absorbent gas supplied from the supply groove 11 (or 11) enters the space PW via the clearance D4 (or D5). Also, since the gas in the clearance D4 (or D5) is exhausted to the outside through the exhaust annular groove 1 18 (or 120), a part of the gas outside the wafer gas purge skirt 36 is exhausted. Even if the gas enters the clearance D 4 (or D 5), this gas is exhausted to the outside through the exhaust annular groove 118 (or 120).

If the type of purge gas in the barrel 19 of the projection optical system PL is different from the type of purge gas in the space PW, the type is located at the lower end of the projection optical system PL (the side closer to the wafer W). The holding mechanism H2 of the lens L2 shown in FIG. 7A needs to be sufficiently airtight so that both gases are not mixed.

Since the projection optical system PL is fixed to the first frame 34, the wafer gas skirt 36 and the projection optical system PL may be hermetically joined (fixed) via a sealing member such as an O-ring. It is possible. However, the wafer gas purge scar 36 is vibrated by driving the wafer stage WST, etc., and the vibration is generated by the projection optical system. When there is a possibility that the light may be transmitted to the PL to deteriorate the imaging characteristics, it is preferable to arrange them closely at predetermined intervals as in the present embodiment.

As described in the present embodiment, when light in the vacuum ultraviolet region is used as the exposure light E as in the present embodiment, the absorption gas from the inside of the illumination system housing 2 and the inside of the barrel of the projection optical system PL is used. Of course must be eliminated. For this reason, in this embodiment, the illumination system housing 2 is connected to the regas supply device 50 by an air supply pipe 10 as shown in FIG. 2, and connected to a gas recovery device (not shown) by an exhaust pipe 11. It has been. Similarly, the lens barrel 19 is connected to a regas supply device 50 by an air supply pipe 30 and connected to a gas recovery device (not shown) by an exhaust pipe 31. Each of the air supply pipes 10 and 30 is provided with an air supply valve (not shown), and each of the exhaust pipes 11 and 31 is provided with an exhaust valve (not shown). A control device (not shown) controls the opening and closing of each air supply valve and each exhaust valve, and the operation and stop of the pump built in the gas supply device 50 as appropriate, so that the inside of the illumination system housing 2 and the projection optical system are controlled. The PL tube 19 is filled with low-absorbing gas, and the concentration of the absorbing gas inside is controlled to a concentration of several ppm or less. It should be noted that a low-absorbent gas may always flow inside these spaces.

In the above description, the case where the low-absorbent gas supplied from the gas supply device 50 into each space is exhausted to the gas recovery device after use, but is not limited thereto. The pipe may be connected to the gas supply device 50, and the used gas may be returned to the gas supply device 50. In this case, a storage tank for low-absorbent gas, a pump, a gas purification device, etc. (all not shown) are built in the gas supply device 50. In this case, the gas purification device built in the gas supply device 50 regenerates the low-absorbency gas whose purity has decreased through the interior of each space to the specified purity again. For example, a HEPA filter or ULPA A filter tie that includes an air filter that removes dust (particles) from a filter and a chemical filter that removes absorptive gases such as oxygen, water vapor, and hydrocarbon-based gases described above. Or a type that uses a cryopump and separates low-absorbent gas and impurities using the difference in vaporization temperature of the substances contained in the gas liquefied by the cryopump. it can. The storage tank inside the gas supply device 50 is connected to an external low-absorbent gas supply source via a valve having a flow rate control function, so that the insufficient low-absorbent gas can be appropriately supplemented. It is desirable to do.

The control device (not shown) controls the opening and closing of the air supply valve and the exhaust valve, and the operation and stop of the pump incorporated in the gas supply device 50 as appropriate, so that each space is filled with the low-absorbent gas. Thus, the concentration of the absorbent gas in the illumination system housing 2 can be suppressed to a concentration of several ppm or less. In this case, even if the low-absorbent gas is circulated for a long time through the circulation path including the gas supply device 50, the concentration of the absorptive gas in each space is reduced by the operation of the gas purification device. Concentrations below P pm can be maintained. Further, the gas supply device 50 may be divided into nine rooms of a first room to a ninth room according to each of the spaces. In this case, the type of the low-absorbent gas in each room may be different.

In the present embodiment, it goes without saying that the light path inside the light transmission optical system is also filled with the low-absorbent gas similarly to the illumination system housing 2.

As can be understood from the above description, the gas supply device 50, the first air supply pipe 60, the air supply valve (not shown), the low-absorbing gas ( A gas supply system that supplies gas (specific gas) is configured. A gas exhaust system that exhausts the gas in the space IM to the outside is configured by a gas recovery device (not shown), the first exhaust pipe 61, and an exhaust valve (not shown). Have been. Further, a gas supply system for supplying a low-absorbent gas (specific gas) to the space MP inside the projection system side gas purge skirt 28 by a gas supply device 50, a first air supply pipe 77, and an air supply valve (not shown). The gas recovery system (not shown), the first exhaust pipe 78, and an exhaust valve (not shown) constitute a gas exhaust system that exhausts the gas in the space MP to the outside. Furthermore, the space inside the wafer-side gas purge skirt 36 is provided by the gas supply device 50, the first air supply pipe 111, and an air supply valve (not shown). A gas supply system that supplies gas (specific gas) to the PW is configured. The gas in the space PW is externalized by a gas recovery device (not shown), the first exhaust pipe 1 12 and an exhaust valve (not shown). A gas exhaust system for exhausting air is configured.

The supply device 80, vacuum pump 79, second air supply line 167, second exhaust line 168, second air supply line 72, and second exhaust line 73 provide a pressurized gas (low absorption) in the clearance D1. And a differential exhaust mechanism that exhausts the gas in the clearance D1 to the outside. In addition, the pressurized gas is supplied into the clearance D2 by the supply device 80, the vacuum pump 79, the second supply line 169, the second exhaust line 171, the second supply line 81, and the second exhaust line 82. A differential exhaust mechanism is configured to supply and exhaust the gas in the clearance D2 to the outside. Also, pressurized gas is supplied into the clearance D3 by the supply device 80, the vacuum pump 79, the second supply line 173, the second exhaust line 175, the second supply line 83, and the second exhaust line 84. In addition, a differential exhaust mechanism that exhausts the gas in the clearance D3 to the outside is configured. In addition, supply device 80, vacuum pump 79, second air supply line 123A to 123C, second exhaust line 124A to 124C, second air supply line 113A to 113C and second air supply line Exhaust pipes 114A to 114C constitute a differential exhaust mechanism that supplies pressurized gas into clearances D4 and D5, respectively, and exhausts gas in clearances D4 and D5 to the outside. .

As described above in detail, according to the exposure apparatus 100 of the present embodiment and the gas purging method performed by the exposure apparatus, the illumination system side gas purge skirt 22 constituting the first shielding mechanism 101 is provided with the reticle stage RS Since the clearance D1 is formed in a state where it is formed between the reticle R and the illumination unit, the clearance D1 is set to an appropriate dimension so that the reticle R disposed on the optical path of the exposure light EL is illuminated. The space between the ILU and the IM can be shielded from the outside air in a somewhat airtight state. Then, in the space IM, the absorption characteristic of the exposure light EL through the first air supply pipe 60 connected to the illumination system side gas purge skirt 22 is changed to the absorption gas described above. Is supplied, and is exhausted through the first exhaust pipe 61 connected to the illumination system side gas purge skirt 22. As a result, the gas in the space IM between the reticle R and the lighting unit ILU can be efficiently replaced with a low-absorbing gas, whereby the absorbing gas can be purged from the space IM. .

In addition, the low-absorbent gas is supplied into the clearance D 1 through an air supply annular groove 67 formed on the lower end surface 22 b of the illumination system side gas purge skirt 22 on the reticle R side, and The gas in the clearance D1 is exhausted to the outside through the exhaust annular groove 68 formed outside the air supply annular groove 67 in the space IM of the lower end face 22b. Thereby, the airtightness of the space IM between the reticle stage RST and the lighting unit ILU is substantially improved, and more accurate gas purge can be realized.

Further, since the projection system side gas purge skirt 28 forming the second shielding mechanism 102 is disposed in a state where a clearance D2 is formed between the projection system side gas purge skirt 28 and the reticle stage RST, the clearance D2 is appropriately dimensioned. By setting to, the space MP between the reticle R arranged on the optical path of the exposure light EL and the projection optical system PL can be shielded from the outside air in a somewhat airtight state. Then, into the space MP, a low-absorbing gas is supplied via a first air supply pipe 77 connected to the projection system-side gas purge cartridge 28, and the first MP connected to the projection system-side gas purge cartridge 28. The air is exhausted through the exhaust pipe 78. Thereby, not only the space IM but also the absorbing gas absorbing the exposure light is removed from the space MP between the reticle R and the projection optical system PL.

Therefore, gas replacement in the space on the optical path of the exposure light EL from the illumination unit ILU to the projection optical system P can be performed with high accuracy without using a large and heavy airtight reticle stage chamber. It is possible to remove the absorbent gas from the space. In this case, the illumination system side gas purge skirt 22 Since the sparged skirt 28 can be small enough to cover the space between the reticle stage RST and the illumination unit ILU or the projection optical system PL, the size and weight of the device can be reduced. In addition, since the clearances D 1 and D 2 are formed between the reticle stage RST and the reticle stage RST as described above, the space on one surface side and the other surface side of the pattern area of the reticle R can be reduced. Despite shielding the reticle stage from outside air, reticle stage RST can be easily accessed from outside.

Also, in the projection system-side gas purge skirt 28, similarly to the illumination system-side gas purge skirt 28, the gas supply annular groove 170 formed on the surface (top end surface 28 a) facing the reticle R is low. The absorbent gas is supplied toward the reticle R (reticle stage RST), and the gas in the clearance D2 is formed outside the air supply annular groove 170 with respect to the space MP on the upper end surface 28a. Since the air is exhausted to the outside through the exhaust annular groove 17 2, the airtightness of the space MP is substantially improved, and more accurate gas replacement is possible.

Further, since a predetermined clearance D3 is formed between the projection optical system PL and the projection system side gas purge skirt 28, the projection system side gas purge skirt 28 generates vibration due to the driving of the reticle stage RST. However, it is possible to prevent the vibration from being transmitted to the projection optical system PL. Even if the clearance D 3 is formed in this way, in the present embodiment, since the gas flow from the inside to the outside of the space MP is formed in the clearance D 3 as in the clearances D 1 and D 2, The airtightness is hardly reduced.

Further, in the present embodiment, the wafer gas purge scar 36 constituting the third shielding mechanism 103 forms a predetermined clearance D4 with the projection optical system PL, and the wafer gas purge scar 36 with the wafer W. With the predetermined clearance D5 formed, it is arranged between the projection optical system PL and the wafer W, and the space inside the wafer gas purge skirt 36 is also subjected to gas replacement in the same manner as the above spaces. Also, in the wafer gas purge skirt 36, the low-absorbent gas is supplied into the clearance D4 from the air supply annular groove 1 17 formed on the surface (the upper end surface 36a) facing the projection optical system PL. At the same time, the gas in the clearance D4 is exhausted to the outside through the exhaust annular groove 118 formed outside the air supply annular groove 117 on the upper end surface 36a. Further, a low-absorbent gas is supplied into the clearance D5 from the air supply annular groove 1 19 formed on the surface (lower end surface 36b) facing the wafer W, and the gas in the clearance D5 is lowered. The air is exhausted to the outside through the exhaust annular groove 120 formed outside the air supply annular groove 119 on the end face 36b. For this reason, the airtightness of the space PW is substantially improved, and more accurate gas replacement is possible.

Therefore, gas replacement in the space on the optical path of the exposure light EL from the projection optical system PL to the wafer W can be performed with high accuracy without using a large and heavy airtight wafer stage chamber. Absorbable gas can be eliminated. In this case, as the wafer gas purge skirt 36, a small one that can cover the space between the wafer W and the projection optical system PL can be used, so that an increase in the size and weight of the apparatus can be suppressed. it can.

As described above, since the low-absorbing gas can be excluded from the space on the optical path of the exposure light EL from the illumination unit ILU to the wafer W, the transmittance of the exposure light EL can be maintained at a high level and the exposure can be performed with high accuracy. Can be performed over a long period of time.

The surface of the gas purge skirt 22 on the illumination system side facing the reticle stage RST (lower end surface 22b) and the surface of the gas purge skirt 28 on the projection system side facing the reticle stage RST (upper end surface 28a) are both flat. The upper and lower surfaces of the reticle stage RST are both flat, so that even when the clearances D 1 and D 2 are sufficiently narrow, when the reticle stage RST is moved, each package skirt 22 , 28 do not contact reticle stage RST. Therefore, while maintaining high airtightness of space IM and MP, reticle stage RST This makes it possible to make a large movement, easily replace the reticle after the movement, or easily perform maintenance of the reticle stage RST.

Further, in the above embodiment, since the Y-axis linear motors 24 A and 24 B for driving the reticle stage RST are arranged outside the purge space, the space in which the gas purge should be performed is reduced, and the gas purge gas is reduced. And the projection optical system PL ゃ Reticle R can be shielded from the generation of dust and heat generated by the scanning of the reticle stage RST, and the stability of the exposure equipment and the adhesion of dust to the reticle (contamination) ) Can be prevented.

In the above embodiment, not only the space between the illumination unit ILU and the projection optical system PL, but also the space between the projection optical system P and the wafer W is almost air-tight by using the wafer gas skirt 36. Although the case where the state is set has been described, the present invention is not limited to this. Since the space between the projection optical system P and the wafer W is usually short, the respective ends of the gas supply pipe and the gas exhaust pipe are located in this space, and the space is provided via the gas supply pipe. By sending the low-absorbing gas into the space and exhausting the gas containing the absorptive gas in the space to the outside through a gas exhaust pipe, the absorbing optical system PL It is possible to exclude from the space on the optical path between and Jeha W. Therefore, such a technique may be combined with the gas purging method of the present invention applied to the reticle side.

In the above-described embodiment, the annular groove for air supply 117 can be omitted between the wafer gas purge skirt 36 and the projection optical system PL. That is, between the wafer gas purge skirt 36 and the projection optical system PL, the gas in the clearance D4 by the annular groove for exhaustion 118, or the external gas and space PW through the clearance D4. May be configured to suck and exhaust the gas. Thus, an exhaust ring is provided between the wafer gas purge skirt 36 and the projection optical system PL. The inflow of oxygen and water vapor outside the wafer gas purge skirt 36 into the space PW can be blocked only by providing the concave grooves 118.

In the above-described embodiment, the case where the illumination system side gas purge skirt 22 is directly fixed to the lower end surface of the illumination unit ILU has been described. However, similarly to the other parts, a predetermined gap is formed. As the lighting system side gas purge skirt

22 may be provided.

That is, as shown in FIG. 8, the clearance D6 can be provided between the illumination system side gas purge skirt 22 and the lower end surface of the housing 2 of the illumination unit ILU. In this case, in order to increase the airtightness of the space IM, the air supply annular groove 370 as the air supply port and the exhaust annular groove 372 as the exhaust port are used as in the past. U-shaped second air supply conduit 3 69 9 and an exhaust annular groove formed in the upper end surface 2 2 a of the side gas purge skirt 22 and communicating with the annular supply groove 37 0 2nd exhaust pipe with a U-shaped cross section formed in communication with 3 7 2

Connect one end of the second air supply pipe 3 8 3 and one end of the second exhaust pipe 3 8 4 to each of 3 7 1 and connect the other end of these second air supply pipe 3 8 3 and the second exhaust pipe 3 8 4 80 and vacuum pump 79, respectively. With this configuration, a gas flow outward from the space IM is formed in the clearance D6 as in the past, so that the inflow of gas from outside the space IM is minimized. Will be.

Also in this case, a part of the low-absorbent gas supplied from the annular groove for air supply 370 enters the space IM via the clearance D6. Further, since the gas in the clearance D 6 is exhausted to the outside through the annular groove for exhaust 3 72, a part of the gas outside the illumination system side gas purge scar 22 enters the clearance D 6. However, this gas is exhausted to the outside through the exhaust annular groove 372.

For this reason, even if vibrations caused by the movement of the reticle stage RST occur in the illumination system gas purge skirt 22 while maintaining the purge performance in the space IM, it is possible to avoid transmission of the vibration to the illumination unit ILU. it can. In this case, the supply device 80, vacuum pump 79, second air supply line 369, second exhaust line 371, second air supply line 383, and second exhaust line 384 allow clearance D A differential exhaust mechanism that supplies pressurized gas (low-absorbent gas) into the clearance D6 and exhausts the gas in the clearance D6 to the outside is configured in the inside of the clearance D6. In the above embodiment, the case where the gas purge method of the present invention is adopted in the exposure apparatus of the step 'and' scan method has been described. However, the present invention is not limited to this, and the exposure method of the step and & The present invention can also be suitably applied to an apparatus (so-called stepper).

FIG. 9 shows a partial cross section of a state near a reticle stage in a stepper type exposure apparatus suitable for applying the gas purging method of the present invention. As shown in FIG. 9, the reticle stage is fixed near a stage main body 130 having a flat plate shape and a rectangular opening 130 a formed in the center of the stage main body 130. A plurality of (for example, four) reticle holders 132 are provided.

Each of the reticle holding portions 13 2 has a concave portion 13 4 formed on the upper surface thereof, and a suction conduit 13 5 formed in communication with the concave portion 13 4. Reticle R is suction-held by suction pipe 1 36 connected to reticle holding section 1 32.

Between the reticle R and the illumination unit ILU, a first shielding mechanism 101 ′ similar to the above embodiment is provided.

The first shielding mechanism 101 'includes an illumination-system-side gas purge skirt 22', and the illumination-system-side gas purge skirt 22 'has the same structure as the first shielding mechanism 101 described above. In addition, a first supply pipe 60 ′, a first exhaust pipe 61 ′, a plurality of second supply pipes 72 ′, and a plurality of second exhaust pipes 73 ′ are connected. The first supply pipe 60 ′ is connected to a gas supply device 50, and the first exhaust pipe 61, is connected to a gas recovery device (not shown). Is the gas purges on the lighting system side The low-absorbing gas is supplied into the generally airtight space IM 'formed by the cart 22', the lighting unit I LU and the reticle R, and the gas in the space IM 'is supplied from the first exhaust pipe 61'. Since the gas is discharged, the space IM 'is replaced with a low-absorbent gas. The second air supply pipe 72 'and the second exhaust pipe 73' are connected to a supply device 80 and a vacuum pump 79, respectively, and from the second air supply pipe 72 ', the illumination system side gas skirt 22' and the reticle R are connected. The pressurized gas is supplied to the clearance D 1 ′ during this time, and the gas in the clearance D 1 ′ is exhausted from the second exhaust pipe 73 ′ by the suction force of the vacuum pump. An outward gas flow is formed from the space IM '.

A second shielding mechanism 102 is provided on the lower surface side of the reticle R, that is, between the reticle R and the projection optical system PL.

The second shielding mechanism 102 includes a projection-system-side gas purge skirt 28 '. The projection-system-side gas purge skirt 28' includes a first air supply pipe 77 'and a first An exhaust pipe 78 ', a plurality of second air supply pipes 8 1', and a plurality of second exhaust pipes 82 'are connected. The first air supply pipe 77 'and the first exhaust pipe 78' are connected to a gas supply device 50 and a gas recovery device (not shown), respectively. As a result, the low-absorbent gas is supplied from the first air supply pipe 77 'into the substantially hermetically sealed space MP' formed by the projection system side gas purge skirt 28 ', the reticle R, and the projection optical system PL. Then, the gas in the space MP 'is discharged from the first exhaust pipe 78', so that the gas in the space MP 'is replaced by the low-absorbent gas.

The second air supply pipe 81 'and the second exhaust pipe 82' are connected to a supply device 80 and a vacuum pump 79, respectively, as in the above embodiment. From the second air supply pipe 81 ', a clearance D2' between the projection system side gas purge skirt 28 'and the reticle R, and a clearance D3 between the projection system side gas purge skirt 28' and the projection optical system PL. , A low-absorbent gas is supplied to the second exhaust pipe 82, and the gas of the clearance D 2 ′ and the clearance D 3 ′ is exhausted from the second exhaust pipe 82. This allows In the clearances D2 'and D3', a gas flow is formed outward from the space MP ', so that the airtightness of the space MP' can be further improved. Here, in the stepper, the reticle is not scanned during the exposure operation (that is, a large operation like a scanning stepper is not performed). Therefore, the gas purge scars constituting the first and second shielding mechanisms are as described above. It can be arranged closer to the reticle R than in the embodiment. That is, the substantially hermetically sealed space IΜ ', MP' formed by each gas purge scar and the like can be a more airtight purge space than the spaces IM, MP of the above embodiment. Therefore, the absorption of the exposure light EL is further suppressed as compared with the above embodiment, and it is possible to realize highly accurate exposure.

In this case, the reticle exchange method can be easily realized by, for example, sliding the reticle R in the direction perpendicular to the plane of FIG.

In the description so far, the exhaust in the space (IM, MP, PW (or IM ', MP')) is performed via the first exhaust pipe connected to each purge scar. However, the present invention is not limited to this, and a configuration in which air is exhausted to the outside through gaps in each space can be adopted.

In the above embodiment, a straight-tube type lens barrel as shown in FIG. 1 is employed as the projection optical system P. Instead, for example, a catadioptric projection optical system is employed. In such a case, the shape of the projection optical system has a bent portion and a protruding portion, but even in such a case, a gas purge skirt is provided on the reticle-side end surface or the wafer-side end surface of the projection optical system. By arranging in close proximity, the present invention can be suitably applied.

Further, in the above embodiment, a predetermined clearance is formed between the end of the projection system side gas purge skirt 28 and the upper end surface of the lens barrel 19 of the projection optical system PL. The end of the side gas purge skirt 28 is configured to face the side of the barrel 19 of the projection optical system PL, and the side of the barrel 19 of the projection optical system PL is configured. A predetermined clearance may be formed between the surface and the surface.

Further, in the above-described embodiment, the configuration in which the differential pumping mechanism is provided between the projection system side gas purge skirt 28 and the projection optical system PL so as not to transmit the vibration has been described. The projection optical system PL may be connected with a film-like connecting member. In this case, it is preferable to use, as the connecting member, a film-shaped member in which generation of a light-absorbing substance is reduced. This film-like member is formed by applying a highly stretchable protective film made of polyethylene via an adhesive to the outer surface of a film-like material made of, for example, ethylene vinyl alcohol resin (EVOH resin). It can be formed by coating a stabilizing film made of aluminum on the inner surface of the film material by vapor deposition or the like. As the EVOH resin, for example, KURARAY Co., Ltd. “Product name EVAL” can be used.

Further, the gas purge method of the present invention can be applied not only to a projection exposure apparatus but also to an inspection optical apparatus used for inspection of a projection optical system mounted on the projection exposure apparatus. This embodiment of the inspection optical device is a second embodiment described next.

<< 2nd Embodiment >>

Next, a second embodiment of the present invention will be described with reference to FIG. Here, the same reference numerals are used for the same or equivalent components as those in the first embodiment, and the description thereof will be simplified or omitted. The second embodiment relates to a case where the space in which the inspection optical system is arranged, which is unique to the inspection optical device that inspects the projection optical system PL, is gas-purged by the gas purging method of the present invention.

FIG. 10 is a cross-sectional view of the inspection unit 200 constituting the inspection optical device, together with the projection optical system PL and the wafer gas purge skirt 103. Although not shown, the gas on the reticle side (above the projection optical system PL) of the inspection optical device is not shown. The sparging method is the same as in the case of the above-mentioned stepper, and the wafer gas purge skirt 103 provided below the projection optical system PL is the same as in the first embodiment. Description is omitted.

As shown in FIG. 10, the inspection section 200 constituting the inspection optical device has a cylindrical shape (a cylindrical shape with a bottom) with one end (lower end) closed and the other surface (upper surface) opened. ) Optical system support housing OB and lenses 16 1, 16 2, 16 3 arranged sequentially along the Z-axis direction in the optical system support housing OB. The inspection optical system 160 as a system, the image sensor 164 as a photodetector disposed below the inspection optical system 160, and the optical system support housing OB are driven in the X-axis direction. An X-axis linear motor MX, a Y-axis linear motor MY for driving the optical system support housing OB in the Y-axis direction, and a flat plate 150 fixed to the upper end surface of the optical system support housing OB. I have.

The lens 16 1 of the inspection optical system 16 0 is held near the upper end of the optical system support housing OB via the lens holder 2 10, and the lens 16 1 and the lens holder Due to 210, the space below the lens 161 in the optical system support housing OB is airtight. Hereinafter, this space is referred to as “space O C J”.

When measuring the aberration of the projection optical system PL using this inspection optical device, as in the first embodiment, since the vacuum ultraviolet light is used, the optical system support housing OB serving as the optical path of the vacuum ultraviolet light is used. The interior (the interior of the space OC) must be replaced with a low-absorbing gas such as nitrogen or a rare gas. For this reason, a through hole 255 as an air supply opening is formed in the optical system support housing OB from the outside to the inside, and the outside of the through hole 255 is supplied through a connector 152. Trachea 1 5 1 is connected. An air supply nozzle 153 is provided inside the through hole 255. In the space 0 C, a low-absorbent gas is supplied from a gas supply device through the air supply pipes 151 and the like. The optical system support housing OB is formed with a through hole 256 as an exhaust opening different from the through hole 255, and an exhaust pipe 1 is provided outside the through hole 255 via a connector 155. 56 is connected. The gas in the space OC is exhausted to the outside of the optical system support housing OB through the exhaust pipe 156 and the like. In this way, the gas in the space OC is replaced by the low-absorbent gas.

The X-axis linear motor MX includes a mover 212 connected to the optical system support housing OB and a stator 214 whose longitudinal direction is in the X-axis direction. The mover 212 is driven in the X-axis direction along the stator 214, whereby the optical system support housing OB is slid in the X-axis direction. The Y-axis linear motor MY includes a mover 216 fixed below the stator 214 of the X-axis linear motor MX, and a stator 218 having a longitudinal direction in the Y-axis direction. I have. The mover 216 is driven in the Y-axis direction along the stator 218, whereby the optical system support housing OB is slid in the Y-axis direction together with the X-axis linear motor MY.

As described above, the optical system supporting housing OB including the inspection optical system 160 and the image sensor 164 is movable in a two-dimensional plane.

The flat plate 150 has, for example, a rectangular shape in plan view (when viewed from above), and has a circular opening 150a formed in the center thereof. The flat plate 150 will be described later in detail.

In the inspection section 200 configured as described above, an image formed by the projection optical system PL is transferred onto lenses 161 to 163 constituting the inspection optical system 160 onto an imaging element 164 such as a CCD. Magnify and project, for example, measure the optical characteristics (such as aberration) of the projection optical system PL. In this case, as described above, since the optical system support housing OB can be moved two-dimensionally by the linear motors MX and MY, all the image light fluxes from each measurement point in the field of view of the projection optical system PL are taken. It can receive light and can measure aberrations at each measurement point in the field of view.

As described above, the flat plate 150 transmits the image light flux from each measurement point in the field of view of the projection optical system. When receiving, even if the optical system support housing OB moves in a two-dimensional plane by the linear motors MY and MX, the lower end surface of the wafer gas purge skirt 36 does not protrude from the flat plate 150. have. That is, by providing the flat plate 150, a substantially airtight space PO is formed between the projection optical system PL, the wafer gas purge skirt 36, and the inspection unit 200, as in the above embodiment. However, in this space PO, the airtight state is always maintained even when the inspection unit 200 moves in the two-dimensional direction for the inspection.

As described above, according to the second embodiment, since the entire optical path from the projection optical system PL to the imaging device 164 of the inspection unit 200 is replaced with a low-absorbing gas, highly accurate projection is performed. Inspection of optical system PL becomes possible.

When CCD is used as the imaging device 164 provided in the optical system support housing OB, it is generally mounted in a ceramic package, and a cover glass is provided on the front surface thereof. However, there is no cover glass suitable for vacuum ultraviolet light in terms of transmittance, and if fluorite / fluorine-added quartz is attached to the power glass, the cover glass and the light-receiving surface of the CCD There is a problem that gas replacement in the space between the two becomes difficult. This point is improved in the following third embodiment.

<< Third embodiment >>

Next, a third embodiment of the present invention will be described with reference to FIGS. 11A and 11B. Here, the same reference numerals are used for the same or equivalent components as those in the above-described second embodiment, and the description thereof will be simplified or omitted.

In the third embodiment, the configuration of the optical system support housing of the second embodiment, the arrangement method of the imaging device (CCD) 164 as a photodetector, and the light transmitting window member 2 above the CCD are described. It is characterized by the provision of 87.

In the present embodiment, instead of the optical system support housing OB of the second embodiment, As shown in FIG. 11A, an optical system support housing OB ′ including a first partial housing OBa and a second partial housing OBb is used. At the boundary between the first partial housing OBa and the second partial housing OBb, a groove 231 is formed, and a light transmitting window member made of fluorite or fluorine-doped quartz is formed in the groove 231. 287 is sandwiched between the upper and lower sides by the partial housings OBa and OBb. In this case, the light transmitting window member 287 is point-contacted by three projections 290 each slightly protruding from both end surfaces of the first partial housing OBa and the second partial housing OBb. Is held.

The reason that the light transmitting window member 287 is held (pinched) at three points at each of the upper and lower points in this manner is that the light transmitting window member 287 is firmly fixed so that the upper and lower spaces are completely airtight. Then, any stress deformation occurs in the light transmitting window member 287, and the same kind of low-absorbing gas is supplied to the upper and lower spaces partitioned by the light transmitting window member 287. In this case, it is desirable to pinch at each of these three points.

Note that an inspection optical system 160 is provided above the second partial housing O BB as in the second embodiment.

A ceramic package 270 as a holding member is hermetically bonded to the lower end surface of the first partial housing OBa via an O-ring 381 with a CCD 164 mounted thereon, and has an approximately S-shaped cross section. It is fixed to the lower end face of the first partial housing OBa via a stopper 279 and a screw 280 in a shape of a circle. In this case, as shown in FIG. 11B, the ceramic package 270 is made of a box-shaped member having a concave portion 270b formed in the center of the upper surface, and the upper end surface 270a has a high flatness. Is set.

In a normal ceramic package, a cover glass is provided on the front surface (upper surface), but in the present embodiment, no cover glass is provided. '' The lower part of the CCD 164 of the ceramic package 270 is used to draw out the electrical wiring 271 from the electric circuit such as the charge transfer control circuit of the CCD 164, as shown in Fig. 11A. The wiring holes 165 are formed. By forming the wiring hole 165 in this way, the electric wiring 271 is drawn out from the wiring hole 165. By connecting to the connection wiring (not shown) externally, it is possible to wire to the CCD 164 without the gas on the top side of the CCD 164 leaking out through the wiring hole 165 Becomes

By the way, on the lower surface side of the ceramic package 270, as shown in FIG. 11A, a belch:!: Element 272 and a heat dissipation device 274 are provided.

The Peltier element 272 has a function of cooling the ceramic package 270 by supplying a predetermined current through a current wiring connected to the Peltier element 272.

The heat dissipation device 274 is provided on the surface of the Peltier element 272 opposite to the ceramic package 270. The radiator 274 has, for example, a liquid pipe 275 provided therein, and cools the Peltier element 272 by flowing a cooling liquid from the liquid supply device (not shown) to the liquid pipe 275. Note that, as the heat dissipation device 274, another device (for example, a cooling fan or the like) may be employed.

The reason for providing the Peltier element 272 and the heat dissipation device 274 in this way is as follows: (1) Regarding the Peltier element 272, when the CCD 164 detects weak light, the SZN ratio (signal Z noise ratio) is improved. This is because it is desirable to cool the CCD 164 because of the necessity of (2) For the heat dissipation device 274, the opposite side of the Peltier element 272 from the CCD (the lower surface in FIG. This is because the temperature of the Peltier element 272 becomes high when it is cooled, so that it is necessary to cool the lower surface side of the Peltier element 272 so that the temperature does not rise much more than the ambient temperature (for example, 23 ° C.).

Here, when the CCD 164 is cooled using the Peltier element 272, the gas near the CCD 164 cooled by the Peltier element 272 becomes a lens disposed above the CCD 164 due to convection or the like and the gas near the lens. Cooling may make the optical performance unstable. Therefore, the light transmission window member 287 is provided as described above. In this case, the space between the light transmitting window member 287 and the CCD 164 also needs to be replaced with a low-absorbing gas so that the vacuum ultraviolet light can be transmitted well without being absorbed. . Therefore, in the present embodiment, as in the past, one end of the air supply pipe 281 is formed as a through-hole 257 as an air supply opening formed from the outside to the inside of the first partial housing OBa. The air supply nozzle 285 is provided on the opposite side of the through-hole 257 from the air supply pipe 281. A low absorptive gas is formed from the gas supply device (not shown) through the air supply pipe 281 and the like by the light transmitting window member 287, the first partial housing OBa, and the ceramic package 270. The space is supplied to the GC. On the other hand, separately from the through hole 2 57, a through hole 2 58 as an exhaust opening formed from the outside to the inside of the first partial housing OB a is connected to the exhaust pipe 28 through a connector 28 4. 2 is connected. The gas in the space GC is exhausted to the outside through the through holes 258, the exhaust pipe 282, and the like. As a result, the gas in the space GC is replaced with the low-absorbing gas.

When it is necessary to cool the CCD 164 to a lower temperature, the light-transmitting window member 284 is used to prevent the gas around the cooled CCD 164 from being transmitted to the optical system located above. It is preferable to provide a large number of light transmitting window members similar to those in FIG.

As described above in detail, according to the third embodiment, the opening of one side of the ceramic package 270 in which the CCD 164 is accommodated with the light receiving surface facing the opening is provided. The peripheral end surface 270a is connected to the first partial housing OBa via a sealing member (O-ring) 381 to shield the space GC including the light receiving surface of the CCD 164 from outside air. . Therefore, the space GC formed by the first partial housing OBa and the ceramic package 270 is a space with good airtightness. Then, a specific gas (low-absorbing gas) having a lower absorption characteristic for light incident on the light receiving element in the space GC than the absorbing gas is supplied to the air supply pipe connected to the first partial housing OBa. The gas in the space GC is exhausted to the outside via an exhaust pipe connected to the first partial housing OBa. This allows spatial GC to be accurate with low-absorbing gas Since the light is well replaced, the light is hardly absorbed before the light is received by the light receiving surface of the CCD 164. Therefore, it is possible to detect the light quantity of the CCD 164 with high accuracy, and when, for example, measuring the optical characteristics of the projection optical system PL based on the result of the light quantity detection, it is necessary to improve the measurement precision. Becomes possible.

In the third embodiment, the air supply pipe 281 and the exhaust pipe 282 for gas replacement in the space GC are connected to the first partial housing OBa. However, the present invention is not limited to this. An opening may be formed in the package 270, and the air supply pipe 281 and the exhaust pipe 282 may be connected to the opening.

In the third embodiment, since the light-transmitting window member 287 needs to be provided, the optical system supporting housing is formed of two partial housings of the first partial housing OBa and the second partial housing OBb. The optical system supporting housing OB ′ is used, but the present invention is not limited to this. If the light transmission window member 287 does not need to be provided, only the second partial housing OBb is used, and the ceramic package is used. 270 may be fixed directly to the second partial housing OBb.

The light source of the exposure apparatus of the above embodiment, F ₂ laser light source, A r F excimer laser light source is not limited like the K r F excimer laser light source, e.g., an infrared region, which is oscillated from the D FB semiconductor laser or fiber laser Or single-wavelength laser light in the visible region is amplified by, for example, a fiber amplifier doped with erbium (or both erbium and ytterbium), and then converted to ultraviolet light using a nonlinear optical crystal. May be used. The magnification of the projection optical system is not limited to a reduction system, and may be any of an equal magnification and an enlargement system.

The illumination unit and projection optical system consisting of a plurality of lenses are incorporated into the main body of the exposure apparatus, optical adjustment is performed, and the wafer stage (or reticle stage in the case of the scan type) consisting of many mechanical parts is exposed. Attach to the equipment body, connect wiring and piping, and assemble each partition that composes the reticle chamber and wafer chamber. The present invention relates to the exposure apparatus 100 and the like according to the above-described embodiment by connecting the piping system of the system, connecting each part to the control system of the system, and further performing overall adjustment (electrical adjustment, operation confirmation, etc.). An exposure apparatus can be manufactured. It is desirable that the exposure apparatus be manufactured in a clean room where the temperature, cleanliness, etc. are controlled. 《Device manufacturing method》

Next, an embodiment of a device manufacturing method using the above-described exposure apparatus in a lithography process will be described.

FIG. 12 shows a flowchart of an example of manufacturing devices (semiconductor chips such as IC and LSI, liquid crystal panels, CCDs, thin-film magnetic heads, micromachines, etc.). As shown in Fig. 12, first, in step 301 (design step), a device function / performance design (for example, a circuit design of a semiconductor device, etc.) is performed, and a pattern for realizing the function is performed. Do the design. Subsequently, in step 302 (mask manufacturing step), a mask on which the designed circuit pattern is formed is manufactured. On the other hand, in step 303 (wafer manufacturing step), a wafer is manufactured using a material such as silicon.

Next, in step 304 (wafer processing step), using the mask and wafer prepared in steps 301 to 303, an actual circuit is formed on the wafer by lithography technology or the like as described later. Etc. are formed. Next, in step 304 (device assembling step), device assembling is performed using the wafer processed in step 304. This step 305 includes processes such as a dicing process, a bonding process, and a packaging process (chip encapsulation) as necessary.

Finally, in step 360 (inspection step), inspections such as an operation confirmation test and a durability test of the device created in step 305 are performed. After these steps, the device is completed and shipped.

Figure 13 shows the detailed flow of step 304 above for a semiconductor device. An example is shown. In FIG. 13, in step 31 (oxidation step), the surface of the wafer is oxidized. In step 312 (CVD step), an insulating film is formed on the wafer surface. In step 3 13 (electrode formation step), electrodes are formed on the wafer by vapor deposition. In step 3 14 (ion implantation step), ions are implanted into the wafer. Each of the above steps 311 to 3114 constitutes a pre-processing step of each stage of wafer processing, and is selected and executed according to a necessary process in each stage.

In each stage of the wafer process, when the above-mentioned pre-processing step is completed, the post-processing step is executed as follows. In this post-processing step, first, in step 315 (resist forming step), a photosensitive agent is applied to the wafer. Subsequently, in step 316 (exposure step), the circuit pattern of the mask is transferred to the wafer by the lithographic system (exposure apparatus) and the exposure method described above. Next, in Step 317 (development step), the exposed wafer is developed, and in Step 318 (etching step), the exposed members other than the portion where the resist remains are removed by etching. Then, in step 319 (resist removing step), unnecessary resist after etching is removed.

By repeating these pre-processing and post-processing steps, multiple circuit patterns are formed on the wafer.

If the device manufacturing method of the present embodiment described above is used, the exposure apparatus of the first embodiment is used in the exposure step (step 316), so that the exposure light transmittance can be maintained well over a long period of time. The reticle pattern can be transferred onto the wafer with high precision. As a result, the productivity of highly integrated devices can be improved. Industrial applicability As described above, the gas purging method of the present invention is suitable for gas replacement of a space between an optical device and an object arranged on the optical path of light. Further, the exposure apparatus of the present invention is suitable for improving the exposure accuracy while suppressing an increase in the size and weight of the apparatus. Further, the device manufacturing method of the present invention is suitable for producing a highly integrated device.

Claims

The scope of the claims

1. A gas purging method for gas purging a space between an optical device and an object arranged on an optical path of light having a predetermined wavelength,

At least a space between the optical device and the object is shielded from outside air in a state where a predetermined first clearance is formed between the object and a specific object that is one of holding members that hold the object. Arranging a shielding member to perform;

Supplying a specific gas having lower absorption characteristics to the light than the absorbing gas to a space inside the shielding member through an air supply opening formed in the shielding member.

2. In the gas purging method according to claim 1,

A gas purging method, further comprising: exhausting gas in a space inside the shielding member to the outside through an exhaust opening formed in the shielding member.

3. In the gas purging method according to claim 1,

The method according to claim 1, wherein the first clearance is about 3 mm or less.

4. In the gas purging method according to claim 3,

A predetermined gas is supplied into the first clearance via an air supply port formed on an end surface of the shielding member facing the specific object, and the gas in the first clearance is supplied to the space on the end surface. A gas purging method, further comprising the step of exhausting air to the outside through an exhaust port formed outside the air supply port.

5. The gas purging method according to claim 1, wherein The gas purging method, wherein the shielding member reduces transmission of vibration to the optical device.

6. The gas purging method according to claim 5, wherein

The gas purging method, wherein the shielding member is disposed in a state where a predetermined second clearance is formed between the shielding member and the optical device.

7. The gas purging method according to claim 6, wherein

The method according to claim 1, wherein the second clearance is about 3 mm or less.

8. The gas purging method according to claim 7, wherein

A predetermined gas is supplied into the second clearance via an air supply port formed on an end face of the shielding member facing the optical device, and the gas in the second clearance is supplied to the space on the end face. A gas purging method, further comprising the step of: exhausting air to the outside through an exhaust port formed outside the air supply port.

9. A gas purging method for purging a space including a light receiving surface of a photodetector used for an optical device having an optical system irradiated with light of a predetermined wavelength,

One surface is open, and the end face around the opening of the holding member, in which the photodetector is accommodated with the light receiving surface facing the opening, is disposed inside a part of the optical device through a sealing member. And shielding the space including the light receiving surface of the photodetector from the outside air;

A specific gas having a lower light absorption characteristic than the absorbing gas is supplied to the space through an air supply opening formed in one of the component and the holding member. Gas is formed on either the component or the holding member Exhausting to the outside through the exhaust opening.

10. The gas purging method according to claim 9, wherein

Forming a through hole in advance on a portion of the holding member on which the photodetector is mounted; and taking out an electric wiring from the photodetector to the outside from the back surface side of the photodetector via the through hole. A gas purge method further comprising:

11. The gas purging method according to claim 9, wherein

A gas purge method further comprising a step of cooling the holding member.

12. The gas purging method according to claim 11, wherein

A gas purging method, wherein the cooling of the holding member is performed by connecting a Peltier element to a surface of the holding member opposite to the photodetector.

13. The gas purging method according to claim 12,

A gas purging method, further comprising a step of cooling a side of the Velchi X element opposite to the holding member.

14. The gas purging method according to claim 9, wherein

A step of arranging a light transmissive member on a side of the component to which the holding member of the optical device is coupled, opposite to the holding member, to partition a space including a light receiving surface of the photodetector into a plurality of spaces. A gas purge method further comprising:

15. An exposure apparatus for transferring a pattern formed on a mask onto a substrate, comprising: an illumination optical system for illuminating the mask with light of a predetermined wavelength; A state in which a predetermined first clearance is formed between the specific object, which is one of the mask and a mask holding member that holds the mask, and the illumination optical system; and A first shielding member that shields a first space including an area corresponding to at least a pattern area of the mask on the illumination optical system side of the mask from outside air;

An exposure apparatus comprising: a first gas supply system configured to supply a specific gas having lower absorption characteristics to the light than the absorptive gas to the first space via an air supply opening formed in the first shielding member.

16. The exposure apparatus according to claim 15, wherein

A projection optical system for projecting light emitted from the mask on the substrate; and a mask disposed between the specific object and the projection optical system, wherein the transmission of vibration to the projection optical system is reduced. A second shielding member that shields at least the second space including the pattern region of the mask from the outside air on the side of the projection optical system; and the specific gas through an air supply opening formed in the second shielding member. An exposure apparatus, further comprising: a second gas supply system that supplies the second gas to the second space.

17. The exposure apparatus according to claim 16, wherein

An exposure apparatus, wherein the second shielding member is disposed with at least a predetermined second clearance formed between the second shielding member and the specific object.

18. The exposure apparatus according to claim 17,

A first gas exhaust system that exhausts gas in the first space to the outside through an exhaust opening formed in the first shielding member;

A second gas exhaust system that exhausts gas in the second space to the outside through an exhaust opening formed in the second shielding member.

19. The exposure apparatus according to claim 17,

An exposure apparatus, wherein at least one of the first and second clearances is about 3 mm or less.

20. The exposure apparatus according to claim 19,

A predetermined gas is supplied into the first clearance from an air supply port formed on an end face of the first shielding member facing the specific object, and the gas in the first clearance is supplied to the first clearance on the end face. An exposure apparatus, further comprising a differential exhaust mechanism for exhausting air to the outside via an exhaust port formed outside the air supply port with respect to one space.

21. The exposure apparatus according to claim 19,

A predetermined gas is supplied toward the specific object from an air supply port formed on an end surface of the second shielding member facing the specific object, and the gas in the second clearance is supplied to the second surface of the end surface. An exposure apparatus further comprising a differential exhaust mechanism for exhausting air to the outside through an exhaust port formed outside the air supply port with respect to a space.

22. The exposure apparatus according to claim 17,

An adjusting mechanism provided at an end of the first shielding member on the specific object side, the adjusting mechanism being capable of adjusting the first clearance over the entire circumference of the first shielding member; and the identification of the second shielding member. An adjusting mechanism provided at an end on the object side, the adjusting mechanism being capable of adjusting the second clearance over the entire circumference of the second shielding member.

23. The exposure apparatus according to claim 17,

A predetermined third clearance is provided between the second shielding member and the projection optical system. An exposure apparatus characterized by being formed.

24. The exposure apparatus according to claim 23,

The exposure apparatus according to claim 1, wherein the third clearance is about 3 mm or less.

25. The exposure apparatus according to claim 23,

A predetermined gas is supplied into the third clearance from an air supply port formed on the end face of the second shielding member facing the projection optical system, and the gas in the third clearance is supplied to the third face on the end face. An exposure apparatus further comprising a differential exhaust mechanism for exhausting the two spaces to the outside through an exhaust port formed outside the air supply port.

26. The exposure apparatus according to claim 17,

The end surface of the first shielding member facing the specific object and the end surface of the second shielding member facing the specific object are both flat surfaces, and the surfaces of the specific object facing these end surfaces are both flat surfaces. An exposure apparatus, comprising:

27. The exposure apparatus according to claim 17,

A substrate holding member for holding the substrate;

A drive device for driving the mask holding member in a predetermined scanning direction; and a driving device for synchronously moving the mask holding member and the substrate holding member in a predetermined scanning direction.

An exposure apparatus, wherein at least a part of the driving source is disposed outside the first space and the second space.

28. The exposure apparatus according to claim 27,

The length of the first shielding member in the scanning direction is at least: It is determined based on the approach distance by which the mask holding member moves in the acceleration region and the deceleration region before and after the synchronous movement to be performed, and the length of the pattern region of the mask in the scanning direction. Exposure apparatus.

29. The exposure apparatus according to claim 17,

A third space that is disposed between the substrate and the projection optical system and shields a third space on the projection optical system side of the substrate from outside air in a state where at least a predetermined third clearance is formed between the substrate and the projection optical system; 3 shielding members;

And a third gas supply system that supplies the specific gas to the third space via an air supply opening formed in the third shielding member.

30. The exposure apparatus according to claim 29,

An exposure apparatus further comprising a gas exhaust system that exhausts gas in the third space to the outside through an exhaust opening formed in the third shielding member.

31. In the exposure apparatus according to claim 29,

An exposure apparatus, wherein the third shielding member is disposed in a state where a predetermined fourth clearance is formed between the third shielding member and the projection optical system.

3 2. The exposure apparatus according to claim 31,

An exhaust mechanism that exhausts the gas in the fourth clearance to the outside via an exhaust port formed on an end surface of the third shielding member facing the projection optical system.

33. The exposure apparatus according to claim 32,

The exhaust mechanism discharges the gas in the third space via the fourth clearance. An exposure apparatus characterized by exhausting air to a section.

34. The exposure apparatus according to claim 33,

The exposure apparatus, wherein the third gas supply system supplies the specific gas to the third space via the fourth clearance.

35. The exposure apparatus according to claim 29, wherein

A predetermined gas is supplied into the third clearance from an air supply port formed on the end face of the third shielding member facing the substrate, and the gas in the third clearance is supplied to the third space on the end face. An exposure apparatus further comprising a differential exhaust mechanism for exhausting air to the outside via an exhaust port formed outside the air supply port.

36. The exposure apparatus according to claim 15, wherein

An exposure apparatus, wherein a predetermined second clearance is formed between the first shielding member and the illumination optical system.

37. The exposure apparatus according to claim 36,

The exposure apparatus according to claim 1, wherein the second clearance is about 3 mm or less.

38. The exposure apparatus according to claim 36,

A predetermined gas is supplied into the second clearance from an air supply port formed on an end surface of the first shielding member facing the illumination optical system, and a gas in the second clearance is supplied to the first surface of the end surface. An exposure apparatus further comprising a differential exhaust mechanism that exhausts air to the outside of one space through an exhaust port formed outside the air supply port.

39. The exposure apparatus according to claim 15, wherein A second space that is disposed between the substrate and the projection optical system and shields a second space on the projection optical system side of the substrate from outside air in a state where at least a predetermined second clearance is formed between the substrate and the projection optical system. Two shielding members;

A second gas supply system that supplies the specific gas to the second space via an air supply opening formed in the second shielding member.

40. The exposure apparatus according to claim 39,

An exposure apparatus further comprising a gas exhaust system for exhausting gas in the second space to the outside via an exhaust opening formed in the second shielding member.

41. The exposure apparatus according to claim 39, wherein

An exposure apparatus, wherein the second shielding member is disposed in a state where a predetermined third clearance is formed between the second shielding member and the projection optical system.

42. The exposure apparatus according to claim 41, wherein

An exhaust mechanism that exhausts gas in the third clearance to the outside through an exhaust port formed on an end surface of the second shielding member facing the projection optical system.

43. The exposure apparatus according to claim 42, wherein

An exposure apparatus, wherein the exhaust mechanism exhausts gas in the second space to the outside via the third clearance.

44. The exposure apparatus according to claim 43, wherein

The exposure apparatus, wherein the second gas supply system supplies the specific gas to the second space via the third clearance.

45. The exposure apparatus according to claim 39, wherein

A predetermined gas is supplied into the second clearance from an air supply port formed on an end surface of the second shielding member facing the substrate, and the gas in the second clearance is supplied to the second space on the end surface. An exposure apparatus further comprising a differential exhaust mechanism for exhausting air to the outside through an exhaust port formed outside the air supply port.

46. In the exposure apparatus according to claim 39,

An exposure apparatus, further comprising an adjustment mechanism provided at an end of the second shielding member on the substrate side, the adjustment mechanism being capable of adjusting the second clearance over the entire circumference of the second shielding member.

47. The exposure apparatus according to claim 35, wherein

A substrate holding member for holding the substrate;

A driving device that synchronously moves the mask holding member and the substrate holding member in a predetermined scanning direction.

48. In the exposure apparatus according to claim 47,

The length of the first shielding member in the scanning direction is at least a running distance by which the mask holding member moves in an acceleration region and a deceleration region before and after the synchronous movement in which the exposure is performed, and An exposure apparatus, which is determined based on a length of a pattern area in the scanning direction.

49. The exposure apparatus according to claim 48,

An exposure apparatus, wherein a length of the first shielding member in the scanning direction is further determined based on a length of the illumination area in which the mask is illuminated by the light in the scanning direction. ,

50. An exposure apparatus for transferring a mask pattern illuminated by exposure light onto a substrate via a projection optical system,

A space disposed between the substrate and the projection optical system without contacting the substrate and the projection optical system, and a space including an optical path of the exposure light between the substrate and the projection optical system is exposed to outside air. Exposure device, comprising a shielding member for shielding from light.

51. The exposure apparatus according to claim 50,

By sucking and exhausting a gas in a clearance formed between the substrate and the shielding member or between the projection optical system and the shielding member, a space shielded by the shielding member is removed from the outside air. An exposure apparatus for shielding.

52. The exposure apparatus according to claim 51,

Supplying a specific gas having a low absorption property to the exposure light into a clearance formed between the substrate and the shielding member or between the projection optical system and the shielding member. Exposure apparatus characterized by the above-mentioned.

5 3. A device manufacturing method including a lithographic process,

A device manufacturing method, comprising: performing exposure using the exposure apparatus according to claim 15 in the lithographic process.