JP2005183623A - Mirror cylinder, method for adjusting pressure thereof, exposure device and method for manufacturing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mirror cylinder for efficiently adjusting the quantity of light absorbing substances or contaminating substances in a mirror cylinder, a method for adjusting the pressure of the mirror cylinder, an exposure device for efficiently manufacturing a device with a high integration degree, and a method for manufacturing the device. <P>SOLUTION: A barrier member 60 having predetermined pressure resistivity, and covering cover glass 43 is formed on both ends of a projection system mirror cylinder body 27 through a packing 61 so as to be attachable/detachable, and a division space 62 in an air-tight state to the outside is formed between the barrier member 60 and the cover glass 43. Then, a pressure adjusting tube 64 extended from a pressure reducing pump 65 is connected to the projection system mirror cylinder body 27 and the barrier member 60 so that a space 69 and a division space 62 in the projection system mirror cylinder body 27 can be pressure-reduced by the pressure reducing pump 65. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a lens barrel including a plurality of optical elements such as lenses and mirrors, and a lens barrel body that holds the optical elements. The present invention also relates to a pressure adjusting method for adjusting the pressure in the lens barrel. Furthermore, the present invention relates to an exposure apparatus used in a photolithography process of a manufacturing process of various devices such as a semiconductor element, a liquid crystal display element, an imaging element, and a thin film magnetic head. In addition, the present invention relates to a device manufacturing method for manufacturing the various devices.

  This type of exposure apparatus is provided with an illumination optical system that illuminates a mask, such as a reticle or photomask, on which a predetermined pattern is formed, with predetermined exposure light. In addition, a projection optical system that exposes the image of the pattern onto a substrate (wafer, glass plate, or the like) coated with a photosensitive material such as a photoresist by illumination of the illumination optical system is provided. These illumination optical system and projection optical system are composed of a plurality of optical elements such as lens elements and mirrors, and are accommodated in a lens barrel.

In such an exposure apparatus, the wavelength of exposure light has been shortened in order to meet the recent demand for finer circuit patterns. Recently, an exposure apparatus using KrF excimer laser light in the far ultraviolet region (λ = 248 nm), ArF excimer laser light in the vacuum ultraviolet region (λ = 193 nm), F ₂ laser light (λ = 157 nm), etc. as exposure light. Has been developed.

  By the way, when the exposure light having such a wavelength is used, the following problems have been clarified. That is, oxygen, water vapor, hydrocarbon gas, or gaseous organic substances, gaseous ammonium salts, sulfates, nitrates, or other inorganic substances in the space through which the exposure light passes (such as the interior space of the lens barrel) If the light-absorbing substance is present, the exposure light is absorbed before reaching the substrate, and the energy of the exposure light is greatly reduced, or the reaction with the exposure light generates a cloudy substance on the surface of the optical element. It is a problem. This problem is particularly noticeable when vacuum ultraviolet light is used as exposure light and cannot be ignored. In addition to this, when there is a drive mechanism for driving an optical element, a stage for mounting a photomask or a substrate, etc. in the exposure apparatus, a coating material for the wire for supplying power to the drive mechanism and transmitting signals. Organic substances etc. are volatilized from a very small amount. Such a volatilized substance can also be a light-absorbing substance that absorbs the exposure light and a pollutant that contaminates the optical element. Furthermore, so-called degassing such as a volatile matter in which the attached matter that has adhered to the inner wall of the optical element and the lens barrel that houses the optical element is gradually volatilized during exposure can also become the light-absorbing substance and the contaminant. .

In particular, when light having a short wavelength equal to or less than F ₂ laser light is used, the exposure light emitted from the light source is extremely absorbed by the light-absorbing substance, and its energy is significantly reduced before reaching the substrate. Sometimes. As described above, when the energy of the exposure light itself decreases or the transmittance of the exposure light decreases due to fogging of the optical element, the exposure light energy reaching the substrate may be insufficient. As a result, the exposure efficiency of the exposure apparatus is lowered, and there is a concern that the yield of products may be reduced.

  Therefore, in recent years, an exposure apparatus has been developed that uses an inert gas, for example, a rare gas such as nitrogen, helium, or argon, to replace the gas existing in the internal space of the lens barrel through which the exposure light passes. . That is, an inert gas is supplied to the internal space, and the gas containing the light-absorbing substance and the contaminant is discharged out of the space.

However, the conventional configuration is equipped with an inert gas supply mechanism that replaces the interior space with the inert gas, but only reduces the concentration of the light-absorbing substance and the contaminant in the interior space. Met. However, as the exposure light, especially in the case of employing the light of F ₂ laser following a short wavelength is sometimes very presence of the light-absorbing substance and the trace contaminants is problematic. Among such light-absorbing substances, particularly, water has a large absorption coefficient for exposure light having a short wavelength equal to or less than F ₂ laser light, and simply supplying a dry inert gas into the internal space provides the internal space. The removal of water deposited with a thickness of several molecules on the wall surface of the optical element and the surface of the optical element requires a very long time, and thus there is a great interest in the removal. For this reason, there is a great demand for a structure that efficiently discharges a small amount of light-absorbing material or contaminant in the internal space to the extent that the exposure light with the short wavelength as described above is not affected. Yes.

  The present invention has been made paying attention to such problems existing in the prior art. The purpose is to provide a lens barrel capable of efficiently adjusting the amount of light-absorbing substances and contaminants in the lens barrel, a pressure adjusting method for the lens barrel, an exposure apparatus capable of efficiently manufacturing a highly integrated device, and a device It is to provide a manufacturing method.

  In order to achieve the object, an invention according to claim 1 of the present application provides a lens barrel including a plurality of optical elements and a lens barrel body that holds the plurality of optical elements. A space partitioning mechanism that forms a partitioning space between the optical element and the optical element housed in the lens barrel body, the space in the lens barrel body, and the space partitioning mechanism. A pressure adjusting mechanism that adjusts the pressure of at least one of the compartment spaces formed by the above.

  In the invention according to claim 1 of the present application, it is possible to depressurize the space in the lens barrel body and the partition space, and efficiently discharge light-absorbing substances and contaminants existing in the internal space to the outside of the lens barrel body. can do. For this reason, even when it is necessary to accurately replace the internal space of the lens barrel body with a predetermined gas, the amount of light-absorbing substances and contaminants in the lens barrel body can be reduced with a small amount of the predetermined gas in a short time. Can be adjusted.

  Further, in the invention according to claim 2 of the present application, in the invention according to claim 1, the pressure adjusting mechanism adjusts the space in the lens barrel body and the partition space to substantially the same pressure. It is a feature.

  In the invention according to claim 2 of the present application, since a large pressure difference is not generated between the space in the lens barrel body and the partition space, the optical element that partitions the space in the lens barrel body and the partition space. On the other hand, a non-uniform pressure load does not act. For this reason, even if it adjusts the pressure of the space in the said lens-barrel main body and the said division space, it is avoided that the said optical element deform | transforms and the optical performance can be maintained highly.

  In the invention according to claim 3 of the present application, in the invention according to claim 1 or 2, the pressure adjusting mechanism includes a communication path that communicates the space in the lens barrel body and the partition space. It is characterized by having.

According to the third aspect of the present invention, the space in the barrel main body and the partition space can be adjusted to substantially the same pressure simultaneously with a simple configuration.
Moreover, the invention according to claim 4 of the present application is the invention according to any one of claims 1 to 3, wherein the pressure adjusting mechanism includes a space in the barrel body, the partition space, It connects to the exhaust apparatus which exhausts the gas of this outside.

  In the invention according to claim 4 of the present application, the light-absorbing substance and the pollutant in the space in the lens barrel body and the partition space are quickly discharged to the outside together with the gas originally present in those spaces. Can do. In addition, by reducing the pressure in both spaces, the volatilization of light-absorbing substances and contaminants adhering to the walls and optical elements that form both spaces is accelerated, so these materials can be removed more efficiently. be able to.

  The invention according to claim 5 of the present application is the invention according to any one of claims 1 to 4, wherein the pressure adjusting mechanism includes a space in the barrel main body, the partition space, and the like. Is suppressed to be smaller than the pressure limit of the optical element forming the partition space.

In this invention of Claim 5, the said optical element which forms the said division space can avoid the deformation | transformation by the said pressure difference, and can suppress the fall of the optical performance.
The invention according to claim 6 of the present application is the invention according to any one of claims 1 to 5, wherein the pressure adjusting mechanism includes a space in the barrel main body and a partition space. It has an on-off valve that allows or blocks the flow of gas between at least one and the outside.

  In the invention according to claim 6 of the present application, by appropriately opening and closing the on-off valve, the state of gas discharge from the space in the barrel main body and the compartment space, and the supply of predetermined gas to each space It is possible to easily switch between a state and a state where each space is replaced with a predetermined gas.

  The invention according to claim 7 of the present application is the invention according to any one of claims 1 to 6, wherein the pressure adjusting mechanism supplies a predetermined gas to the space in the barrel body. A gas supply mechanism for supplying is provided.

  In the invention according to claim 7 of the present application, after adjusting the pressure of the space in the lens barrel body, a predetermined gas can be immediately supplied into the space. The amount of can be suitably adjusted.

  The invention according to claim 8 of the present application is the invention according to any one of claims 1 to 7, wherein the space partitioning mechanism is detachable from an end of the barrel body. It is characterized by comprising a partition member provided on the surface.

  In the invention according to claim 8 of the present application, when the lens barrel body is not used, the partition member is used as a lid of the lens barrel body to protect the optical element or accommodate the exposure apparatus from a clean room. It is possible to suppress fogging of the optical element due to contaminants leaking into the housing in a trace amount. Further, the barrel main body can be easily switched to the use state by detaching the partition member from the barrel main body or withdrawing from the optical path of the exposure light.

  The invention described in claim 9 of the present application is characterized in that in the invention described in claim 8, it further comprises a partition displacement device that displaces the partition member relative to the end of the lens barrel body. is there.

  According to the ninth aspect of the present invention, when the lens barrel body is not used, the optical element can be protected by the partition member, and when the lens barrel body is used, the partition wall displacement device causes the partition wall to move. The partition member can be easily retracted from the optical path of the exposure light by displacing the member.

  The invention according to claim 10 of the present application is the pressure adjustment method for a lens barrel including a plurality of optical elements and a lens barrel body holding the plurality of optical elements, and at least of both ends of the lens barrel body. A space partition mechanism is provided at one end, a partition space is formed between the space partition mechanism and the optical element accommodated in the lens barrel body, and the space in the lens barrel body and the partition space The pressure of at least one of the above is adjusted.

According to the tenth aspect of the present invention, the same operation and effect as the first aspect of the invention can be obtained.
The invention described in claim 11 is an exposure apparatus that exposes an image of a pattern formed on a mask onto a substrate. The lens barrel according to any one of claims 1 to 9. It is characterized by comprising.

  In the invention according to claim 11 of the present application, the exposure accuracy is improved, and even a fine pattern can be exposed with high accuracy. The exposure apparatus of the present invention is particularly suitable for an exposure apparatus that uses vacuum ultraviolet light as exposure light.

  The invention described in claim 12 of the present application is characterized in that, in the invention described in claim 11, the lens barrel is a projection optical system that projects an image of the pattern onto the substrate. is there.

In the invention according to claim 12 of the present application, the time for adjusting the projection optical system to a predetermined state can be greatly shortened.
The invention described in claim 13 is a device manufacturing method including a lithography process, wherein the exposure is performed using the exposure apparatus according to claim 11 or 12 in the lithography process. To do.

In the invention according to claim 13 of the present application, a highly integrated device can be manufactured with high yield.
Next, together with the inventions described in the above claims, technical ideas extracted from the following embodiments will be described below together with their functions and effects.

  (1) The pressure adjusting mechanism is switched and connected to an exhaust device for exhausting gas in the lens barrel body or the gas supply mechanism in accordance with the pressure in the space in the lens barrel body. Item 8. The lens barrel according to Item 7.

If comprised in this way, according to the pressure of the space in the said lens-barrel main body, the discharge | emission of the gas in a lens-barrel main body and the supply of the predetermined gas in the same space can be switched easily.
(2) The lens barrel according to claim 8, wherein the partition member is disposed so as to be able to contact and separate from an end portion of the lens barrel main body.

  If constituted in this way, when separating the partition member joined to the end of the lens barrel body from the end, contact between the optical element facing the end and the partition member can be avoided, The optical performance of the optical element can be kept good.

(3) The barrel according to claim 8 or (2), wherein the partition member forms the partition space in an airtight manner with respect to the outside of the barrel body.
If comprised in this way, when depressurizing the inside of the said division space, it can suppress that a light-absorbing substance and a contaminant are newly taken in into the division space and the lens-barrel main body from the exterior of a lens-barrel main body.

  (4) The partition wall member is formed of a pressure-resistant material that can withstand a pressure difference between the inside and outside of the partition space that occurs when the partition space is in a decompressed state lower than atmospheric pressure. The lens barrel according to any one of (3) above.

  According to this structure, when the pressure in the partition space is reduced to be equal to the pressure in the space in the lens barrel body, the external environment in which the lens barrel body is disposed in the optical element forming the partition space. It is possible to more reliably avoid the action of a high pressure, and to more reliably suppress deformation of the optical element.

  (5) The partition member is provided with a check valve that allows only passage of gas from the partition space to the outside. The lens barrel according to any one of the above.

If comprised in this way, it can maintain in the state with which the inside of division space was satisfy | filled with the predetermined gas, suppressing the penetration | invasion of the light absorption substance and contaminant from the outside.
(6) The optical elements forming the partition space are arranged inside the barrel main body from the partition member and the end surface of the barrel main body, and (2) to (5), The lens barrel according to any one of the above.

  If comprised in this way, when displacing a partition member to the direction which cross | intersects the optical axis of exposure light, the said partition member contacts the optical element which is arrange | positioned at the edge part of a lens-barrel main body, and forms a division space. It is avoided. Thereby, the influence on the optical performance of the said optical element by interference with a partition member and the said optical element can be excluded.

(7) The lens barrel according to any one of claims 1 to 9, and (1) to (6), wherein the wavelength of light passing through the interior is 190 nm or less.
The lens barrels according to claims 1 to 9 and (1) to (6) are particularly suitable as a lens barrel that allows light having a wavelength of 190 nm or less, which is extremely influenced by light-absorbing substances and contaminants, to pass therethrough. Further, the resolution performance of the exposure apparatus can be improved by mounting the lens barrel according to any of the above claims and (1) to (6).

  As described above, in the present invention, it is possible to efficiently adjust the amount of light-absorbing substances and contaminants in the lens barrel. In addition, there is an effect that a highly integrated device can be efficiently manufactured.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments in which the present invention is embodied in an exposure apparatus for manufacturing a semiconductor element and a semiconductor element manufacturing method using the exposure apparatus will be described with reference to FIGS.
As shown in FIG. 1, the exposure apparatus includes an exposure light source 21 as a light source, an exposure apparatus main body 22, and a beam matching unit (hereinafter referred to as “BMU”) 23. The exposure light source 21 is a laser light source that emits, for example, F ₂ laser light (λ = 157 nm) as the exposure light EL. The BMU 23 includes a plurality of optical elements, and the plurality of optical elements are accommodated in the BMU chamber 29. The BMU 23 optically connects the exposure light source 21 and the exposure apparatus main body 22, and the exposure light EL emitted from the exposure light source 21 through the BMU 23 is guided into the exposure apparatus main body 22.

  The exposure apparatus main body 22 transfers an image of a pattern formed on a reticle R as a mask onto a wafer W as a substrate by irradiation with exposure light EL. Hereinafter, a schematic configuration of the exposure apparatus main body 22 will be described.

  In the chamber 24 of the exposure apparatus main body 22, an illumination system barrel main body 25 as a lens barrel and a projection system barrel main body 27 as a lens barrel are sequentially arranged in the optical axis direction of the exposure light EL introduced through the BMU 23. Is arranged. The lens barrel bodies 25 and 27 and the BMU chamber 29 form a space including the optical path of the exposure light EL from the exposure light source 21 to the wafer W. The chamber 24 includes an air conditioner (not shown), and the interior of the chamber 24 is maintained at a predetermined temperature and humidity under the control of the main control system 30 that controls the operation of the exposure apparatus main body 22 as a whole. It is supposed to be.

  An illumination optical system 33 for illuminating the reticle R is accommodated in the illumination system barrel body 25. The illumination optical system 33 includes optical elements such as a plurality of mirrors 34, a fly-eye lens (which may be a rod integrator) 35 that forms an optical integrator, and a condenser lens 36. The fly-eye lens 35 forms a large number of secondary light sources that illuminate the reticle R with a uniform illuminance distribution on the rear surface thereof when the exposure light EL from the exposure light source 21 is incident. Behind the fly-eye lens 35, a reticle blind 37 for shaping the shape of the exposure light EL is disposed.

  Disc-shaped parallel flat glass 38 is disposed as a part of optical elements of the illumination optical system 33 at the BMU side opening 25a and the mask side opening 25b at both ends of the illumination system barrel body 25. In addition, parallel flat glass 38 is also disposed in the light source side opening 29a and the illumination optical system side opening 29b at both ends of the BMU chamber 29. The parallel flat glass 38 is made of a material (synthetic quartz, fluorite, etc.) that transmits the exposure light EL.

  A plurality (four in this example) of internal spaces 39 are formed in the illumination system barrel body 25 via parallel flat glass 38. In the internal space 39, optical elements such as a mirror 34, a fly-eye lens 35, and a condenser lens 36, and a reticle blind 37 are accommodated alone or in combination.

  The projection system barrel main body 27 accommodates a projection optical system 42 for projecting an image of a pattern on the reticle R illuminated by the illumination optical system 33 onto the wafer W. As shown in FIG. 2, the projection optical system 42 includes two cover glasses 43 and a plurality (four in this example) of optical elements such as lens elements 44. In the projection system barrel body 27, a space 69 is formed in the projection system barrel body 27 by the inner wall of the projection system barrel body 27 and the cover glass 43.

  Further, as shown in FIG. 1, a reticle stage RST is disposed between the projection optical system 42 and the illumination optical system 33. By this reticle stage RST, the reticle R on which a predetermined pattern is formed is held so as to be movable in a plane orthogonal to the optical axis of the exposure light EL.

  A wafer stage WST is disposed on the image plane side of the projection optical system 42. By this wafer stage WST, the wafer W coated with a photoresist having photosensitivity to the exposure light EL can be moved in a plane perpendicular to the optical axis of the exposure light EL, and finely moved along the optical axis. It is designed to be held as possible.

  A movable mirror that reflects a laser beam from an interferometer (not shown) is fixed to the end of the reticle stage RST. The position of the reticle stage RST in the scanning direction is constantly detected by the interferometer, and is driven in the predetermined scanning direction under the control of the main control system 30.

  Further, a movable mirror that reflects a laser beam from an interferometer (not shown) is fixed to the end of wafer stage WST, and the position in the plane where wafer stage WST is movable is always detected by the interferometer. The Wafer stage WST is configured to be movable not only in the scanning direction but also in a direction perpendicular to the scanning direction within a movable plane under the control of main control system 30. As a result, a step-and-scan operation in which scanning exposure is repeated for each shot area on the wafer W is possible.

  Here, when the circuit pattern on the reticle R is scanned and exposed to the shot area on the wafer W by the step-and-scan method, the illumination area on the reticle R is shaped into a rectangle (slit) by the reticle blind 37. The This illumination region has a longitudinal direction in a direction orthogonal to the scanning direction on the reticle R side. At the time of exposure, the reticle R is moved at a predetermined speed Vr in the scanning direction, so that the circuit pattern on the reticle R is sequentially illuminated from one end side to the other end side in the slit-like illumination region. As a result, the circuit pattern on the reticle R in the illumination area is projected onto the wafer W via the projection optical system 42 to form a projection area.

  Here, since the wafer W is in an inverted imaging relationship with the reticle R, the wafer W is moved in a direction opposite to the scanning direction of the reticle R at a predetermined speed Vw in synchronization with the scanning of the reticle R. As a result, the entire shot area of the wafer W can be exposed. The scanning speed ratio Vw / Vr is in accordance with the reduction magnification of the projection optical system 42, and the circuit pattern on the reticle R is accurately reduced and transferred onto each shot area on the wafer W.

  Further, a purge gas supply system 50 as a gas supply mechanism is connected to an opening 49 formed in a wall portion that partitions the BMU chamber 29, the internal space 39, and the space 69. An inert gas as a purge gas is supplied to the BMU chamber 29, the internal space 39, and the space 69 from the tank 51 in the utility plant of the micro device factory through the purge gas supply system 50 and each opening 49. It has become. Here, the inert gas is a single gas selected from nitrogen, helium, neon, argon, krypton, xenon, radon, or the like, or a mixed gas thereof.

Here, in this purge gas, it accumulates on the surfaces of optical elements such as the mirror 34, fly-eye lens 35, condenser lens 36, parallel flat glass 38, cover glass 43 and lens element 44 under irradiation of the exposure light EL. Contaminants that cause a clouding phenomenon or light-absorbing substances such as water that strongly absorbs F ₂ laser light may be contained as impurities.

  For this reason, in the air supply pipe 52 of the purge gas supply system 50, the filter 53 and the purge gas for removing impurities including the pollutants and light absorbing substances contained in the purge gas are adjusted to a predetermined temperature, and the purge gas contains A temperature-controlled dryer 54 that removes moisture is interposed. The BMU chamber 29, the internal space 39, and the space 69 are connected to an exhaust duct 56 of a semiconductor element manufacturing factory through a purge gas discharge pipe 55.

  In addition, as contaminants existing in the BMU chamber 29, the internal space 39, and the space 69, for example, organosilicon compounds, ammonium salts, sulfates, volatilized substances from the resist on the wafer W, and components used for driving parts are used. Volatilized substances from the slidability improving agent, volatilized substances from the coating layer of the wiring for supplying power to or supplying signals to the electrical components in the chamber 24, and the like. Therefore, the purge gas discharged to the outside of the factory may contain these contaminants.

Next, the configuration of the projection system barrel body 27 that houses the projection optical system 42 will be described.
As shown in FIG. 2, the projection system barrel main body 27 is configured by fixing a plurality of barrel units 59 holding the lens elements 44 to each other by bolts or the like. At both ends of the projection system barrel main body 27, partition members 60 constituting a part of the space partition mechanism are detachably provided via packings 61 so as to cover the cover glass 43. The partition member 60 is made of a pressure resistant material such as metal.

  Here, “detachable” means that the partition wall member 60 can be completely removed from the projection system barrel body 27, and that the exposure light EL is in a state where the partition wall member 60 is attached to the projection system barrel body 27. It includes both a configuration that can be retracted out of the optical path.

  At this time, a partition space 62 that is airtight with respect to the outside is formed between the partition wall member 60 and the cover glass 43. An air supply pipe 52 of a purge gas supply system 50 is connected to the partition wall member 60 so that purge gas can be supplied to the partition space 62, and an open / close valve 68 is provided in the air supply pipe 52 connected to the partition wall member 60. It has been.

  A pressure adjustment pipe 64 extends from a decompression pump 65 as an exhaust device connected to the purge gas discharge pipe 55, and the pressure adjustment pipe 64 is branched into two. In the pressure adjusting pipe 64, an electromagnetic valve 66 as an on-off valve is provided between the pressure reducing pump 65 and the branch point. One of the two pressure adjustment pipes 64 is connected to the projection system barrel main body 27, and the other is connected to the partition wall member 60. Therefore, the pressure adjustment pipe 64 functions as a communication path that connects the space 69 in the projection system barrel body 27 and the partition space 62. The pressure adjusting pipe 64, the pressure reducing pump 65, and the electromagnetic valve 66 constitute a pressure adjusting mechanism.

  Of the lens barrel unit 59, the air supply pipe 52 of the purge gas supply system 50 is connected to the lens barrel unit 59a located at the upper end of the projection system lens barrel body 27, and the air supply in the vicinity of the lens barrel unit 59a is connected. The pipe 52 is provided with an on-off valve 63. On the other hand, in the lens barrel unit 59, the lens barrel unit 59 b positioned substantially at the center of the projection system lens barrel body 27 supports the projection system lens barrel body 27 on a frame (not shown) of the exposure apparatus main body 22. A flange FLG is provided. A purge gas discharge pipe 55 is connected to the lens barrel unit 59c located at the lower end of the projection system barrel main body 27 in the lens barrel unit 59, and an on-off valve 67 is connected to the purge gas discharge pipe 55. Is provided.

  When adjusting the amount of light-absorbing substance or contaminant in the projection system barrel body 27, first, the electromagnetic valve 66 is opened. Then, the decompression pump 65 is operated to decompress the space 69 and the partition space 62 in the projection system barrel main body 27 to a state lower than the atmospheric pressure (preferably, a state close to vacuum). At this time, since the space 69 and the partition space 62 in the projection system barrel main body 27 are communicated with each other by the pressure adjusting pipe 64, the spaces 69 and 62 have substantially the same pressure. For this reason, the pressure difference between the spaces 69 and 62 does not exceed the pressure limit of the cover glass 43. Further, at this time, a large pressure difference is generated inside and outside the partition space 62 across the partition wall member 60, and a load due to the pressure difference acts on the partition wall member 60. However, since the partition wall member 60 is made of a pressure resistant material, it is reliably avoided that a load due to the pressure difference acts on the cover glass 43.

  The space 69 and the partition space 62 in the projection system barrel main body 27 are depressurized to a state close to vacuum, and the state is maintained for a predetermined time, and then the electromagnetic valve 66 is closed. Next, the opening / closing valve 63 and the opening / closing valve 68 are gradually opened, and the purge gas is gradually injected from the air supply pipe 52 into the space 69 and the partition space 62 in the projection system barrel body 27. At this time, similarly to the above, the opening degree of the on-off valves 63 and 68 is adjusted so that the flow rate of the purge gas does not impact the lens element 44 and the cover glass 43 in the projection system lens barrel body 27. It is desirable.

Therefore, according to the present embodiment, the following effects can be obtained.
(A) In the projection system barrel body 27, the pressure adjusting pipe 64 connected to the decompression pump 65 is connected to the projection system barrel body 27. For this reason, the space 69 in the projection system barrel main body 27 can be brought into a reduced pressure state lower than the atmospheric pressure by the decompression pump 65. Thereby, the light-absorbing substance and the contaminant existing in the space 69 can be efficiently volatilized and discharged together with the gas existing inside the projection system barrel main body 27. Therefore, even when the space 69 in the projection system barrel main body 27 needs to be replaced with a purge gas with extremely high accuracy, the light-absorbing substance and the contaminants can be removed from the projection system barrel main body 27 with a small amount of purge gas in a short time. The space 69 can be discharged to the outside. Such a projection system barrel main body 27 is particularly suitable as a barrel of an exposure apparatus that uses exposure light EL of 190 nm or less, such as F ₂ laser light, which is extremely influenced by light-absorbing substances and contaminants in the exposure process. Yes, it is possible to dramatically improve the efficiency of the exposure process.

  (B) In the projection system barrel main body 27, the pressure in the space 69 in the projection system barrel main body 27 and the pressure in the partition space 62 are substantially equalized by the pressure adjusting pipe 64 connected to the decompression pump 65. Can be adjusted. Thereby, even if the pressure of the space 69 in the projection system barrel main body 27 is adjusted, a large pressure difference does not occur between the space 69 and the partition space 62, and the cover that partitions both the spaces 69 and 62 is covered. The non-uniform pressure load acting on the glass 43 is suppressed. Therefore, the cover glass 43 is prevented from being deformed with the pressure adjustment of the space 69 in the projection system barrel main body 27, and the optical performance can be maintained high.

  (C) In the projection system barrel main body 27, the space 69 and the partition space 62 in the projection system barrel main body 27 are communicated with each other by the pressure adjusting pipe 64, so that a simple configuration using the decompression pump 65 or the like is used. Thus, the spaces 69 and 62 can be simultaneously adjusted to substantially the same pressure. In addition, by suppressing the pressure difference between the space 69 and the partition space 62 in the projection system barrel main body 27 to be smaller than the pressure limit of the cover glass 43 forming the partition space 62, the cover glass 43 has a pressure difference. Therefore, it is possible to avoid deformation, and it is possible to suppress a decrease in optical performance.

  (D) In the projection system lens barrel body 27, the pressure reducing pump 65 is connected to the purge gas discharge pipe 55. For this reason, the light-absorbing substance and the pollutant in the space 69 and the partition space 62 in the projection system barrel main body 27 are removed by the decompression pump 65 together with the gas originally present in the spaces 69 and 62 and the purge gas discharge pipe 55 and It can be quickly discharged outside the exposure apparatus via the exhaust duct 56. Also, by reducing the pressure in the spaces 69 and 62, the volatilization of the light-absorbing substances and contaminants adhering to the wall surfaces forming the spaces 69 and 62, the lens element 44, the cover glass 43, and the like is accelerated. Therefore, removal of those substances can be performed more efficiently.

  (E) In the projection system barrel main body 27, a partition wall member 60 is detachably provided at an end thereof. For this reason, when the projection system barrel main body 27 is not used, the cover glass 43 can be protected by using the partition wall member 60 as a lid of the projection system barrel main body 27. Further, when the projection system barrel main body 27 is not used, fogging of the cover glass 43 and the lens element 44 due to contaminants leaking from the clean room into the chamber 24 that accommodates the exposure apparatus can be suppressed. it can. When the projection system barrel main body 27 is used, the partition wall member 60 is detached from the projection system barrel main body 27 or retracted from the optical path of the exposure light EL, so that the pattern image on the reticle R is transferred to the wafer. When transferring onto W, the partition wall member 60 does not hinder the exposure operation.

  (F) The partition member 60 is made of a pressure resistant material such as metal. Therefore, when the pressure in the partition space 62 and the pressure in the space 69 in the projection system barrel main body 27 are reduced to a pressure lower than the atmospheric pressure, the projection system lens barrel is placed on the cover glass 43 that forms the partition space 62. It is more reliably avoided that the high pressure of the external environment where the main body 27 is arranged acts. For this reason, deformation of the cover glass 43 can be more reliably suppressed.

  (G) The partition member 60 is provided at the end of the projection system barrel main body 27 via the packing 61. For this reason, a partition space 62 that is airtight with respect to the outside of the space 69 in the projection system barrel body 27 is formed between the partition wall member 60 and the cover glass 43. Accordingly, when the inside of the partition space 62 is depressurized, light absorbing substances and contaminants newly enter the partition space 62 and the space 69 in the projection system barrel body 27 from outside the space 69 in the projection system barrel body 27. Incorporation can be suppressed.

(Example of change)
In addition, you may change embodiment of this invention as follows.
As shown in FIG. 3, the projection system barrel main body 27 may be provided with an actuator 70 as a partition wall displacement device to move the partition member 60. In this case, the rod 71 of the actuator 70 can be rotated around the optical axis of the projection optical system 42 and can be expanded and contracted in the same optical axis direction, so that the partition wall member 60 is moved relative to the end of the projection system barrel body 27. You may arrange | position so that contact / separation is possible.

  In this way, when the projection system barrel body 27 is not used, the partition member 60 can be joined to the end of the projection system barrel body 27 by the actuator 70 to protect the cover glass 43. Further, when the projection system barrel main body 27 is used, as shown in FIG. 4, the partition member 60 can be easily retracted from the optical path of the exposure light EL by moving the partition member 60 by the actuator 70.

  Thus, when retracting the partition wall member 60 from the optical path of the exposure light EL, the rod 71 of the actuator 70 is extended in the optical axis direction of the projection optical system 42 so that the partition wall member 60 is positioned at the end of the projection system barrel body 27. Separate from. Then, the rod 71 is rotated to retract the partition member 60 from the optical path. In this way, interference between the partition wall member 60 and the cover glass 43 when the partition wall member 60 is rotated can be more reliably suppressed.

  In the exposure apparatus main body 22 of the embodiment, the air supply pipe 52 of the purge gas supply system 50 may be connected to the electromagnetic valve 66, and the air supply pipe 52 connected to the lens barrel unit 59a and the partition wall member 60 may be omitted. In other words, the pressure adjustment pipe 64 may partially play a role of the air supply pipe 52 that supplies the purge gas to the projection system barrel body 27. Then, by the operation of the electromagnetic valve 66, the purge gas is supplied to the space 69 of the projection system barrel body 27 via the air supply pipe 52 and the space 69 in the projection system barrel body 27 is evacuated by the decompression pump 65. It can be done by switching.

  In this way, by appropriately switching (opening / closing) the electromagnetic valve 66, gas is discharged from the space 69 and the partition space 62 in the projection system barrel main body 27, and purge gas is supplied to the spaces 69 and 62. Can be easily switched to a state in which the spaces 69 and 62 are replaced with purge gas. Further, since the air supply pipe 52 connected to the lens barrel unit 59a and the partition wall member 60 can be omitted, the connection structure of the air supply pipe 52 with respect to the projection system lens barrel body 27, and hence the configuration of the projection system lens barrel body 27 can be eliminated. Can be simple.

In the embodiment, the lens barrel of the present invention is embodied in the projection system barrel main body 27 that accommodates the projection optical system 42, but may be embodied in the illumination system barrel main body 25 that accommodates the illumination optical system 33. .
The partition member 60 may be provided with a check valve that allows only passage of gas from the partition space 62 to the outside. In this way, it is possible to maintain the compartment space 62 filled with the purge gas while suppressing the entry of the light-absorbing substance and contaminants from the outside.

  The cover glass 43 may be arranged inside the projection system barrel body 27 from the partition wall member 60 and the end surfaces of the projection system barrel body 27. In this way, when the partition member 60 is displaced in the direction intersecting the optical axis of the exposure light EL, the partition member 60 is disposed at the end of the projection system barrel body 27 and contacts the cover glass 43. Can be avoided, and it can be excluded that the optical performance of the cover glass 43 is affected.

A configuration may be adopted in which the partition wall member 60 is screwed to the end portion of the projection system barrel main body 27.
In the embodiment, a sensor for measuring a gas state in the space 69 inside the projection system lens barrel body 27, for example, an oxygen concentration, a moisture concentration, or the like, may be attached. Then, the discharge of gas from the space 69 and the partition space 62 and the supply of purge gas to the spaces 69 and 62 may be switched according to the measurement result of the sensor. In this way, it is possible to supply the purge gas with the space 69 in the projection system barrel main body 27 in a predetermined state, for example, in a state where the oxygen concentration and the water amount are not more than the predetermined amount. Thereby, the projection system barrel body 27 can be more reliably maintained in a predetermined state. Further, switching between gas discharge and purge gas supply can be easily performed.

In the embodiment, the projection optical system 42 is not limited to the refraction type, but may be a catadioptric type or a reflection type.
The exposure apparatus of the present invention is not limited to a reduction exposure type exposure apparatus, and may be, for example, a 1X exposure type or an expansion exposure type exposure apparatus.

  A glass substrate or silicon from a mother reticle is used to manufacture reticles or masks used in not only microdevices such as semiconductor elements but also light exposure apparatuses, EUV exposure apparatuses, X-ray exposure apparatuses, and electron beam exposure apparatuses. The present invention can also be applied to an exposure apparatus that transfers a circuit pattern to a wafer or the like. Here, in an exposure apparatus using DUV (deep ultraviolet) or VUV (vacuum ultraviolet) light, a transmission type reticle is generally used. As a reticle substrate, quartz glass, quartz glass doped with fluorine, fluorite, fluoride, and the like are used. Magnesium or quartz is used.

  Used not only for exposure devices used for manufacturing semiconductor elements, but also for manufacturing exposure devices that transfer device patterns onto glass plates, thin film magnetic heads, etc., used for manufacturing displays including liquid crystal display elements (LCDs). The present invention can also be applied to an exposure apparatus that transfers a device pattern to a ceramic wafer or the like, and an exposure apparatus that is used to manufacture an image sensor such as a CCD.

  The present invention can also be applied to a step-and-repeat type batch exposure apparatus that transfers a mask pattern to a substrate while the mask and the substrate are stationary, and sequentially moves the substrate stepwise.

As a light source of the exposure apparatus, for example, g-line (λ = 436 nm), i-line (λ = 365 nm), KrF excimer laser (λ = 248 nm), ArF excimer laser (λ = 193 nm), Kr ₂ laser (λ = 146 nm) ), Ar ₂ laser (λ = 126 nm) or the like may be used. In addition, a single wavelength laser beam in the infrared region or visible region oscillated from a DFB semiconductor laser or fiber laser is amplified by, for example, a fiber amplifier doped with erbium (or both erbium and ytterbium), and a nonlinear optical crystal is obtained. It is also possible to use harmonics that have been converted into ultraviolet light.

In addition, the exposure apparatus of each embodiment is generally manufactured as follows, for example.
That is, first, the plurality of lens elements 44 and the cover glass 43 constituting the projection optical system 42 are accommodated in the projection system barrel body 27 of the embodiment. An illumination optical system 33 including optical elements such as a mirror 34 and lenses 35 and 36 is housed in the illumination system barrel body 25. Then, the illumination optical system 33 and the projection optical system 42 are incorporated in the exposure apparatus main body 22 to perform optical adjustment. Next, a wafer stage WST (including a reticle stage RST in the case of a scan type exposure apparatus) composed of a large number of mechanical parts is attached to the exposure apparatus main body 22 to connect wiring. Then, after connecting the pipe of the purge gas supply system 50 for supplying the purge gas into the optical path of the exposure light EL, further comprehensive adjustment (electrical adjustment, operation check, etc.) is performed.

  Here, each component constituting each lens barrel is assembled after removing impurities such as processing oil and metal substances by ultrasonic cleaning or the like. The exposure apparatus is preferably manufactured in a clean room in which the temperature, humidity, and pressure are controlled and the cleanness is adjusted.

Next, an embodiment of a device manufacturing method using the above-described exposure apparatus in a lithography process will be described.
FIG. 5 is a flowchart showing a manufacturing example of a device (a semiconductor element such as an IC or LSI, a liquid crystal display element, an image pickup element (CCD or the like), a thin film magnetic head, a micromachine, or the like).

  As shown in FIG. 5, first, in step S101 (design step), a function / performance design (for example, circuit design of a semiconductor device) of a device (microdevice) is performed, and a pattern design for realizing the function is performed. Do. Subsequently, in step S102 (mask manufacturing step), a mask (such as a reticle R) on which the designed circuit pattern is formed is manufactured. On the other hand, in step S103 (substrate manufacturing step), a substrate (wafer W when silicon material is used) is manufactured using a material such as silicon or glass plate.

  Next, in step S104 (substrate processing step), using the mask and substrate prepared in steps S101 to S103, an actual circuit or the like is formed on the substrate by lithography or the like, as will be described later. Next, in step S105 (device assembly step), device assembly is performed using the substrate processed in step S104. Step S105 includes processes such as a dicing process, a bonding process, and a packaging process (chip encapsulation or the like) as necessary.

  Finally, in step S106 (inspection step), inspections such as an operation confirmation test and a durability test of the device manufactured in step S105 are performed. After these steps, the device is completed and shipped.

  FIG. 6 is a diagram showing an example of a detailed flow of step S104 of FIG. 5 in the case of a semiconductor device. In FIG. 6, in step S111 (oxidation step), the surface of the wafer W is oxidized. In step S112 (CVD step), an insulating film is formed on the surface of the wafer W. In step S113 (electrode formation step), an electrode is formed on the wafer W by vapor deposition. In step S114 (ion implantation step), ions are implanted into the wafer W. Each of the above steps S111 to S114 constitutes a pretreatment process at each stage of the wafer processing, and is selected and executed according to a necessary process at each stage.

  At each stage of the wafer process, when the above pre-process is completed, the post-process is executed as follows. In this post-processing process, first, a photosensitive agent is applied to the wafer W in step S115 (resist formation step). Subsequently, in step S116 (exposure step), the circuit pattern of the mask (reticle R) is transferred onto the wafer W by the lithography system (exposure apparatus) described above. Next, in step S117 (developing step), the exposed wafer W is developed, and in step S118 (etching step), the exposed members other than the portion where the resist remains are removed by etching. In step S119 (resist removal step), the resist that has become unnecessary after the etching is removed.

Multiple circuit patterns are formed on the wafer W by repeatedly performing these pre-processing and post-processing steps.
If the device manufacturing method of this embodiment described above is used, in the exposure process (step S116), the resolution can be improved by the exposure light EL in the vacuum ultraviolet region, and the exposure amount can be controlled with high accuracy. Therefore, the exposure accuracy can be improved, and a highly integrated device having a minimum line width of about 0.1 μm can be manufactured with a high yield.

1 is a schematic block diagram that shows an exposure apparatus of an embodiment. 1 is a schematic cross-sectional view of a projection system barrel body of an embodiment. The principal part perspective view which shows the closed state of the partition member in the projection type lens-barrel main body of the example of a change. The principal part perspective view which shows the open state of the partition member in the projection type lens-barrel main body of the example of a change. The flowchart which shows the manufacturing method of a device. The flowchart which shows the manufacturing method of a semiconductor element.

Explanation of symbols

  25 ... Illumination system barrel body as a barrel, 27 ... Projection system barrel body as a barrel, 33 ... Illumination optical system, 34 ... Mirror as optical element, 35 ... Fly eye lens as optical element, 36 ... Condenser lens as an optical element, 38 ... Parallel flat glass as an optical element, 39 ... Internal space, 42 ... Projection optical system, 44 ... Lens element as an optical element, 50 ... Purge gas supply system as a gas supply mechanism, 59, 59a, 59b, 59c ... barrel unit, 60 ... partition member, 62 ... partition space, 64 ... pressure adjusting pipe constituting the pressure adjusting mechanism, 65 ... pressure adjusting mechanism, decompression pump as exhaust device, 66 ... An electromagnetic valve as an on-off valve, 63, 67, 68 ... on-off valve, 69 ... space, 70 ... an actuator as a partition displacement device, 71 ... partition change Rod of the apparatus, EL ... exposure light, the reticle as R ... mask, W ... wafer as a substrate.

Claims (13)

In a lens barrel that includes a plurality of optical elements and a lens barrel body that holds the plurality of optical elements,
The lens barrel main body has a space partitioning mechanism that is provided at at least one end of the both ends of the lens barrel main body and forms a partition space with the optical element housed in the lens barrel main body. A lens barrel comprising a pressure adjusting mechanism for adjusting the pressure of at least one of an inner space and the partition space formed by the space partition mechanism. The lens barrel according to claim 1, wherein the pressure adjusting mechanism adjusts the space in the lens barrel body and the partition space to substantially the same pressure. 3. The lens barrel according to claim 1, wherein the pressure adjusting mechanism includes a communication path that communicates the space in the lens barrel body and the partition space. The said pressure adjustment mechanism is connected to the exhaust apparatus which exhausts the gas of the space in the said lens-barrel main body and the said division space outside, The Claim 1 characterized by the above-mentioned. The lens barrel described. The said pressure adjustment mechanism suppresses the pressure difference between the space in the said lens-barrel main body and the said division space smaller than the pressure | voltage resistant limit of the said optical element which forms the said division space, The Claim 1 characterized by the above-mentioned. Item 5. The lens barrel according to any one of Items 4 to 4. The pressure adjusting mechanism includes an on-off valve that allows or blocks gas flow between at least one of the space in the barrel main body and the partition space and the outside. The lens barrel according to any one of the above. The lens barrel according to any one of claims 1 to 6, wherein the pressure adjusting mechanism includes a gas supply mechanism that supplies a predetermined gas to a space in the lens barrel main body. The said space division mechanism is provided with the partition member provided so that attachment or detachment is possible with respect to the edge part of the said barrel main body, The lens barrel as described in any one of Claims 1-7 characterized by the above-mentioned. The lens barrel according to claim 8, further comprising a partition displacement device that displaces the partition member with respect to an end portion of the barrel body. In a method for adjusting the pressure of a lens barrel comprising a plurality of optical elements and a lens barrel body that holds the plurality of optical elements,
A space partition mechanism is provided on at least one end of both ends of the lens barrel body,
A partition space is formed between the space partition mechanism and the optical element housed in the lens barrel body, and the pressure of at least one of the space in the lens barrel body and the partition space is adjusted. A method for adjusting the pressure of the lens barrel. In an exposure apparatus that exposes an image of a pattern formed on a mask onto a substrate,
An exposure apparatus comprising the lens barrel according to any one of claims 1 to 9. The exposure apparatus according to claim 11, wherein the lens barrel is a projection optical system that projects an image of the pattern onto the substrate. In a device manufacturing method including a lithography process,
13. A device manufacturing method, wherein exposure is performed using the exposure apparatus according to claim 11 in the lithography process.

Images