JP2005079297A - Original transporting device and semiconductor aligner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the amount of electrostatic charge generated in an original or a pellicle and prevent the electrostatic discharge damage of a circuit pattern in the original upon handling the original or purging inert gas in the space of the pellicle. <P>SOLUTION: The original transporting device is provided with a transporting means or a reticle hand 15 for supporting the original or the reticle 23 employed in the exposure of a semiconductor, and an earth 53 for releasing an electrostatic charge charged on the reticle. The earth is constituted on the fork unit 51 of the transporting means, and a contact area between the earth and the reticle is extremely small with respect to the contact area between an attraction pad 52 on the supporting member or the hand 15 for supporting the reticle previously and the reticle. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a semiconductor manufacturing apparatus for manufacturing a semiconductor such as an LSI, and in particular, a photomask or a reticle (hereinafter referred to as “reticle” as appropriate) or a wafer, a glass plate or the like (hereinafter referred to as “wafer” as appropriate). .)), And a cassette or a carrier in which they are stored. In addition, the present invention relates to an exposure apparatus in which these transport apparatuses are incorporated.

  In an exposure process in a semiconductor manufacturing process, a circuit pattern formed on a photomask is projected and exposed onto a wafer coated with a photosensitive agent to form a circuit pattern, such as 1/4 or 1/5. A photomask used for this reduced projection exposure is called a reticle. The reticle is an insulator because it is made of a highly transparent glass material such as quartz, and a circuit pattern is formed on one surface of the substrate with a metal film such as chromium. For this reason, static electricity accumulates depending on the storage environment and handling conditions, and the circuit pattern on the reticle is destroyed by electrostatic breakdown, which causes a reduction in semiconductor manufacturing yield. Factors that charge the reticle include peeling charge of the reticle support member during reticle handling, fluid friction during cleaning with pure water, and the storage case of the reticle being made of an insulator, leaving the storage environment in an extremely high potential state. In some cases, charges were induced on the reticle side. As a countermeasure for these problems, the storage case is molded from an antistatic material, and the reticle is stored in a potential natural atmosphere to prevent the reticle itself from being charged. Even if a charged reticle is brought in from the outside or charged by handling a reticle hand for transportation, the charge will leak through the support member over time due to the natural storage environment, or into the air. It diffused and attenuated the charging of the reticle.

    In the semiconductor exposure process, if foreign matter or the like is present on the reticle, the foreign matter is transferred onto the wafer together with the pattern and causes a defect. In order to prevent this, the reticle includes a pattern protective film or plate called a pellicle (a film-like material made of a synthetic resin or a plate-like material made of quartz glass, etc. Hereinafter, it is generically called a “pellicle”. ) Is attached. The pellicle is provided at a position offset by a predetermined distance from the reticle pattern surface, and is supported by a pellicle support frame, and the pellicle support frame is attached to the reticle with an adhesive. By using the pellicle, the foreign matter adheres to the pellicle surface that is offset by a predetermined distance from the pattern surface of the reticle, so that it does not form an image directly on the wafer surface during exposure, and appears as illuminance unevenness of illumination light. The influence of time is reduced.

    FIG. 2 is a schematic diagram showing the structure of this pellicle. The pellicle 24 is affixed to the pattern surface side of the reticle 23 using an adhesive or the like, and has a high transmittance for the pellicle support frame 25 provided so as to surround the circuit pattern and the exposure light affixed to one end surface thereof. The pellicle film (or plate) 26 is configured. At this time, the adhesive for attaching the pellicle support frame 25 has a certain degree of film thickness and elasticity so that the surface shape of the pellicle support frame 25 does not cause bending of the reticle 23 or the like. In addition, if the space surrounded by the pellicle 24 and the reticle 23 (hereinafter referred to as the pellicle space) is completely sealed, the pellicle film 26 swells or dents due to a difference in atmospheric pressure inside and outside the pellicle space. Is provided with a vent hole 27 so that there is no pressure difference between inside and outside the pellicle space. Further, a dustproof filter is provided in the ventilation path in order to prevent external foreign substances from entering the pellicle space from the ventilation hole 27.

    For drawing a circuit pattern for creating a reticle, exposure by an electron beam is mainly used. At this time, a reticle formed when a negative resist is used as a resist sensitive to an electron beam is shown in FIG. There was something like that. A circuit pattern 31 for exposure is disposed in the center area of the reticle, and a light shielding pattern 33 is provided on the outer periphery thereof so that exposure light is not transferred to a portion outside the pattern, and the circuit pattern 31 and the light shielding pattern are interposed therebetween. A scribe line 32 for separating 33 is provided. A pellicle support frame 25 is disposed so as to cover the circuit pattern on the reticle, and supports the pellicle film or plate 26 at a position offset by a predetermined distance from the reticle pattern surface. Outside the pellicle support frame 25, when the reticle is set on the reticle stage, an alignment mark 34 for alignment, a code (not shown) for identifying the type of the reticle, and a code used in each process are used. The illustrated process mark and the like are arranged. Various patterns on the reticle are formed of metal such as chrome, and the light shielding pattern 33 extends to the outer peripheral area of the reticle, and the outer peripheral area other than the marks is generally formed of chromium or the like. It was the target.

    In the recent semiconductor exposure, conventional step-and-repeat is required to meet the demands of increasing the chip area by increasing the capacity and functionality of the device and increasing the production efficiency by increasing the number of chips in one shot. From the type of exposure apparatus, a step-and-scan type exposure apparatus (hereinafter referred to as a scanner) having a wide exposure area has become the mainstay. Each stage that holds the wafer and reticle is speeded up to increase the throughput of the apparatus, a linear motor is adopted as a drive source, and a non-contact air guide is used as a guide mechanism in order to make the frictional resistance extremely small. Is adopted. In particular, the reticle stage side projects the circuit pattern on the reticle onto the wafer in a reduced scale. For example, when the reduction ratio is 1/4, the reticle stage needs to be scanned at a speed four times that of the wafer stage. It is said.

    FIG. 4 is a schematic diagram showing an example of a reticle scan stage employed in the scanner. Reference numeral 41 denotes a reticle chuck for holding the reticle during scanning exposure, 42 denotes a top plate which is a structure of the reticle stage, 43 denotes a linear motor movable element connected to the top plate to drive the scan stage, 44 denotes a linear motor stator, 45 Is an air pad for allowing the top plate 42 to float on the air, and 46 is a stage surface plate. The reticle stage 1 is guided by a non-contact air bearing in order to maximize the driving performance of the linear motor, and the top plate 42 is in a state of being air-lifted with respect to the air pad 45.

    Furthermore, in order to achieve higher capacity and higher functionality of the device, it is necessary to increase the mounting density of semiconductor elements, and further miniaturization of circuit patterns is required. Simultaneously with the development of the resist process, there is an increasing demand for a finer exposure line width for the exposure apparatus.

As means for improving the resolving power of the exposure apparatus, there are a method of changing the exposure wavelength to a shorter wavelength and a method of increasing the numerical aperture (NA) of the projection optical system. In recent years, KrF excimer laser having an oscillation wavelength near 248 nm and ArF excimer laser having an oscillation wavelength near 193 nm have been put into practical use from i-line at 365 nm. Further, as a next-generation light source, a fluorine (F ₂ ) excimer laser exposure having an oscillation wavelength near 157 nm has been developed.

In the deep ultraviolet, particularly ArF excimer laser having a wavelength near 193 nm and fluorine (F ₂ ) excimer laser having an oscillation wavelength near 157 nm, there are a plurality of oxygen (O ₂ ) absorption bands in the band near these wavelengths. It is known.

    For example, a fluorine excimer laser has a wavelength as short as 157 nm, and therefore its application to an exposure apparatus is being promoted. However, a wavelength of 157 nm is generally in a wavelength region called vacuum ultraviolet. This is because light absorption by oxygen molecules is large in this wavelength region, so that it hardly transmits light in the atmosphere, and can be applied only in an environment where the pressure is lowered to near vacuum and the oxygen concentration is sufficiently lowered.

Therefore, in the optical path of the exposure optical system of a projection exposure apparatus using a deep ultraviolet ray, particularly an ArF excimer laser having a wavelength of about 193 nm or a fluorine (F ₂ ) excimer laser having a wavelength of about 157 nm, as a light source A method is adopted in which the concentration of oxygen present in the optical path is suppressed to a low level of the order of several ppm or less by means of purging with an active gas. The same can be said for moisture (H ₂ O), and it is also necessary to remove it in the order of several ppm.

FIG. 5 is a schematic diagram showing an example of a scanner using a fluorine (F ₂ ) excimer laser as a light source and having a load lock mechanism and a reticle scan stage.
In FIG. 5, reference numeral 1 denotes a reticle stage on which a reticle on which a pattern is drawn is mounted. Reference numeral 2 denotes a projection optical system that projects a pattern on the reticle onto a wafer, such as an illumination optical system for irradiating illumination light on the reticle. Illumination light is routed from an unillustrated fluorine (F ₂ ) excimer laser light source and guided to the exposure unit by an optical system. A casing 8 covers the exposure optical axis around the reticle stage 1 and is purged with an inert gas. Reference numeral 3 denotes an environmental chamber that covers the entire exposure apparatus and manages the environment by supplying clean air controlled to a predetermined temperature, and controls the temperature and humidity in the chamber to a certain level. Reference numeral 4 denotes an air conditioner that supplies clean air whose temperature is controlled to the chamber, and includes an air conditioner that adjusts a predetermined portion such as an optical system to an inert gas atmosphere. Reference numeral 13 denotes a reticle load lock used when the reticle is carried into the housing 8, 15 denotes a reticle hand for transporting the reticle, and 18 denotes a reticle storage for storing a plurality of reticles in the housing 8. 19 is a foreign substance inspection device that measures the size and number of foreign substances such as dust adhering to the reticle surface and pellicle surface, 14 is a SMIF pod containing one or more reticles, and 16 is a SMIF pod 14 and a load lock 13. It is a reticle hand that carries the reticle in between. The reticle is pulled out from the SMIF pod 14 by the hand 16 and carried into the load lock 13. Thereafter, the inside of the load lock 13 is purged with an inert gas, and an inert gas atmosphere equivalent to that in the housing 8 is obtained. Then, the reticle 23 is moved by the reticle hand 15 to the reticle stage 1 or the reticle storage 18 or the foreign matter inspection device. It is conveyed to any one of 19.

Further, as a next-generation light source, development of an exposure apparatus using extreme ultraviolet light (EUV light: Extreme Ultraviolet Light) having a wavelength in the soft X-ray region around 10 to 15 nm or an electron beam (EB: Electron Beam) as a light source. Has also been done. When the wavelength is shortened to EUV light or electron beam, the gas in the air no longer transmits light, and the space through which the exposure light passes is in a high vacuum environment of about 10 ⁻⁴ to 10 ⁻⁵ Pa or more. There is a need to. In an exposure apparatus using EUV light, similarly to an exposure apparatus using fluorine (F ₂ ) excimer laser light, a load lock mechanism is provided in the apparatus, and exposure that is a vacuum environment is performed via the load lock mechanism. In order to take in and out the substrate between the space and the external space which is a normal environment, the apparatus configuration may be the same as that shown in FIG. 5, for example.
JP 2001-284217 A Japanese Patent No. 3300265 JP-A-5-100410 JP 2000-98592 A JP 2001-133960 A JP 2001-133961 A Japanese Patent Publication No. 7-27198 Japanese Patent Laid-Open No. 1-152727

As described above, in an exposure apparatus using ultraviolet rays, particularly ArF excimer laser light and fluorine (F ₂ ) excimer laser light, absorption by oxygen and moisture at wavelengths of ArF excimer laser light and fluorine (F ₂ ) excimer laser light is performed. Therefore, in order to obtain sufficient transmittance and stability, the oxygen and moisture concentrations are reduced, and the vicinity of the projection optical system is purged with an inert gas in order to strictly control these concentrations. In addition, a load lock mechanism is provided at the portion connecting the inside of the purge area and the outside of the purge area. When a reticle or wafer is loaded from the outside, the load inside the load lock mechanism is temporarily blocked by the outside air. After purging with, it was carried into the purge area.

    In such an inert gas purge area and other environments where moisture has been removed significantly, the diffusion of static electricity into the air in the reticle storage state can hardly be expected, and when an externally charged reticle is brought in or for transportation. When static electricity generated by contact peeling due to the handling of the reticle hand is accumulated, the reticle is charged to a high potential, and the circuit pattern on the reticle is electrostatically broken.

    In order to eliminate static electricity on the reticle, a soft X-ray ionizer or the like is installed inside the purge area as proposed in Japanese Patent Application Laid-Open No. 2001-284217 (Patent Document 1), and the reticle is stored or the reticle is used. It has been proposed to prevent electrostatic breakdown of a circuit pattern by removing static electricity at the time of delivery. However, it is necessary to install ionizers at all the delivery positions, which increases the cost of the equipment. Therefore, it is necessary to keep the ionizers at the minimum necessary places such as the load lock and reticle storage, and to prevent electrification due to reticle handling. .

In addition, in the case of an exposure apparatus using EUV light or an electron beam, which is a next generation light source, as described above, since the exposure space is a vacuum environment of about 10 ⁻⁴ to 10 ⁻⁵ Pa, there are only a small amount of gas molecules. In addition, since the gas to be ionized is dilute, a conventionally used ionizer cannot generate sufficient ions, and a sufficient charge removal effect cannot be obtained. Therefore, since there is no effective method for removing static electricity charged on the reticle in a high vacuum environment, it is necessary to prevent contact peeling electrification between the reticle and the substrate holding portion during reticle handling.

    In order to suppress the amount of charge during handling as much as possible, there is a method to select a material for the reticle support that is compatible with the reticle side. If the material is metal, the work function is close. It is good to choose. Also, static electricity generated by contact peeling can be reduced by reducing the contact area of the reticle support. Japanese Patent No. 3300265 (Patent Document 2) proposes a method for suppressing the amount of charge by making the reticle support member on the reticle hand for conveyance conductive and providing a conductive path when the reticle is supported. ing. Accordingly, by grounding all the members that support the reticle in the transport apparatus, it is possible to suppress the charge amount of the reticle to some extent.

    Further, in order to prevent electrostatic breakdown during handling, in order not to cause a potential change around the circuit pattern, JP-A-5-100410 (Patent Document 3) and JP-A-2000-98592 are disclosed. Although it is effective to adopt the reticle disclosed in (Patent Document 4) and the like, static electricity is generated by contact peeling by a handling member, so that an electric field remains in the periphery of the reticle to generate an electric field. There is a possibility of inducing charging of the circuit pattern portion, and a handling method that does not leave a charge on the reticle itself is required.

In order to ensure the transmittance of fluorine (F ₂ ) excimer laser light and its stability, the entire reticle stage (wafer stage) including the projection lens end face and the interferometric optical system for length measurement is arranged in an airtight chamber. In addition to purging the whole with high-purity inert gas, the load lock chamber is installed in the hermetic chamber in order to carry wafers and reticles into and out of this hermetic chamber while keeping the inert gas concentration in the interior constant. Adjacent to each other. However, a pellicle is affixed to the reticle carried into the load lock chamber, and the pellicle space is structured so that it can communicate with the outside air only through a relatively small ventilation hole. Even after reaching the gas concentration, it took a longer time to complete the replacement in the pellicle space, which was a factor that deteriorated productivity. When a valve or a dust filter is disposed in the hole path, there is a disadvantage that the ventilation resistance increases and the replacement time becomes longer.

    In order to increase the gas replacement efficiency in the pellicle space, Japanese Patent Application Laid-Open No. 2001-133960 (Patent Document 5) and Japanese Patent Application Laid-Open No. 2001-133916 (Patent Document 6) actively perform gas replacement in the pellicle. A method has been proposed. These gas replacement stations that actively perform gas replacement in the pellicle space are preferably provided in at least one place such as the load lock 13 and the reticle storage 18 in FIG.

    As a method of actively replacing the gas in the pellicle space, there is a method in which an inert gas is supplied to the vent hole or a nozzle for sucking the inert gas is connected. However, charging is caused by contact peeling when the nozzle is separated. Since the pellicle support frame is generally a metal such as aluminum, a conductive black surface treatment can be applied, but the adhesive that attaches the pellicle support frame to the reticle is an insulator, and the reticle support unit Since the charge cannot be released through the pellicle, static electricity is accumulated in the pellicle support frame.

Further, as the pellicle film material, fluorine resin or the like has been used in KrF, ArF exposure or the like, but in a projection exposure apparatus using a far ultraviolet ray as a light source such as a fluorine (F ₂ ) excimer laser, a conventional fluorine resin or the like is used. In the case of a pellicle film made of the above, durability becomes a problem due to film thickness reduction due to photodecomposition of the film material. Instead, a durable glass pellicle with a thickness of about 0.3 mm to 0.8 mm is used. Proposed. Since these fluororesins and glass pellicles are insulators and are very easily charged, it has been reported that the circuit pattern on the reticle is electrostatically damaged due to the charging of the pellicle film. There was also a need to suppress the charging of the pellicle support frame and pellicle membrane.

    The present invention has been made in view of the above-described problems, and uses ultraviolet light as exposure light, replaces the inside of the apparatus with an inert gas or creates a vacuum environment, and transfers a circuit pattern on an original through a projection optical system. In the exposure device that irradiates the photosensitive substrate, the amount of charge generated on the original or pellicle during the handling of the original or the inert gas purge of the pellicle space is suppressed, and electrostatic damage of the original circuit pattern is prevented. Objective.

    In order to achieve the above object, the original transport apparatus of the present invention is used in an exposure apparatus that uses ultraviolet light as exposure light and irradiates a photosensitive substrate with a circuit pattern formed on the reticle via a projection optical system. And a conveying means for supporting the original plate and conveying it to a predetermined place, and a ground for releasing charges charged on the original plate, and the earth is formed on the conveying means. By doing so, the ground can be contacted in conjunction with the contact peeling between the original and the conveying means, so that the static electricity generated by the contact peeling between the original and the support member such as the reticle hand, reticle chuck or the like can be prevented. Can escape efficiently.

In addition, the contact area of the earth itself with the original plate may be an extremely small area with respect to the contact area between the support member supporting the original plate and the original plate, and may be, for example, 1 mm ² or less. Therefore, the static electricity generated by the contact peeling of the earth itself can be almost ignored.

    In addition, if the static electricity generated by contact peeling leaks in or near the circuit pattern, the circuit pattern may be electrostatically broken due to the potential change around the circuit pattern. It is preferably provided so as to be grounded through an electric resistance or to be in contact with the vicinity of the contact portion between the support member and the original plate.

    Further, by constituting a part or the whole of the ground with an elastic member, the original can be grounded without hindering the delivery operation of the original.

    The semiconductor exposure apparatus of the present invention has a gas supply nozzle that is in close contact with a vent hole provided in the pellicle support frame and supplies gas to the pellicle space, and a ground that releases static electricity charged on the pellicle support frame. The ground may be characterized in that static electricity generated by contact peeling between the original plate and the gas supply nozzle is released. In this case, it is preferable that the ground is provided on the gas supply nozzle and moves integrally with the gas supply nozzle.

    In addition, the semiconductor exposure apparatus of the present invention purges the periphery of the projection optical system with an inert gas and adheres to the vent hole provided in the pellicle support frame when performing ultraviolet light exposure using the original plate with a pellicle, and enters the pellicle space. A gas supply nozzle for supplying gas; a gas discharge nozzle for discharging gas from the pellicle space; and a ground for releasing static electricity charged on the pellicle support frame, wherein the ground is the original plate, the gas supply nozzle, and the gas discharge. It may be characterized in that static electricity generated by contact peeling with the nozzle is released. By doing so, static electricity generated by contact peeling between the pellicle support frame and each nozzle can be efficiently released.

Further, the contact area of the earth itself with the pellicle support frame may be a sufficiently small region as compared with the contact area of each nozzle, and may be, for example, 1 mm ² or less. Therefore, the static electricity generated by the contact peeling of the earth itself can be almost ignored.

    Further, by constituting a part or the whole of the ground with an elastic member, the load on the pellicle can be reduced, and the pellicle support frame can be grounded without deforming the pellicle support frame and the pellicle film or plate.

    The ground is provided on at least one of the gas supply nozzle and the gas discharge nozzle, and preferably moves integrally with either the gas supply nozzle or the gas discharge nozzle. The ground is preferably grounded through an electric resistance.

    In the exposure apparatus of the present invention, the inert gas that substitutes in the optical path of the exposure light may be one selected from nitrogen, helium, and argon.

    In addition, the exposure apparatus of the present invention can include a purge means for filling the inside of the exposure apparatus with an inert gas and an exhaust means for making the inside of the exposure apparatus a vacuum space. A device manufacturing method according to the present invention is characterized in that a device is manufactured using any one of the above semiconductor exposure apparatuses.

    According to the present invention, in a projection exposure apparatus using ultraviolet light such as a fluorine excimer laser or EUV light, or an exposure apparatus that performs exposure using charged particles such as an electron beam, when an original is delivered or with a pellicle When the inside of the original pellicle space is purged with an inert gas, charging of the original and the pellicle can be prevented. As a result, electrostatic breakdown of the circuit pattern on the original plate can be prevented, and a fine circuit pattern without defects can be exposed stably and satisfactorily, improving the yield of semiconductor manufacturing and improving the productivity of the factory. Contributes to improvement.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings, taking as an example the case where the original is a reticle or a photomask.

    FIG. 1 shows an original conveying apparatus according to an embodiment of the present invention, in which 23 is a reticle, 33 is a light-shielding pattern formed of chromium or the like on the lower surface side of the outer periphery of the reticle, and 15 is a reticle hand that conveys the reticle 23. , 51 is a fork for supporting the reticle 23, 52 is a suction pad disposed on the fork 51 for sucking and holding the reticle 23, and 53 is for releasing static electricity generated when the suction pad 52 is separated. And an elastic body that is interposed between the fork 51 and the reticle 23.

    Next, the reticle delivery operation will be described with reference to FIGS. FIG. 6 shows a state in which the reticle 23 is held on the fork 51 of the transporting reticle hand 15 via a suction pad 52 as a support member, and a circuit 31 is formed of chromium or the like at the center of the reticle. A pattern, 25 is a pellicle support frame, 26 is a pellicle film or plate, and 41 is a reticle chuck provided on the reticle stage 1 for attracting and holding the reticle 23 during exposure. The reticle hand 15 is lowered from FIG. 6 to FIG. 7, so that the reticle 23 is transferred to the reticle chuck 41 on the reticle stage 1. At this time, the suction pad 52 and the reticle 23 on the reticle hand 15 are separated and charged, and static electricity is generated in each of the reticle hand 15 and the reticle 23. Since the reticle hand 15 has a conductive path, static electricity leaks. However, since the reticle stage 1 has an insulating structure as described above, normally the static electricity does not escape and remains in the light shielding pattern 33. However, in the configuration of the present invention, since the earth 53 is provided, static electricity generated in the reticle 23 due to contact peeling leaks through the reticle hand 15 using the earth 53 as a conductive path, and remains on the reticle 23. do not do. FIG. 8 shows a state in which the reticle hand 15 is further lowered and the ground 53 is separated from the reticle 23, but the contact area between the ground 53 and the reticle 23 is reduced by setting the contact area of the ground 53 with the reticle to be a minute region. Static electricity generated by peeling can be ignored.

    The ground 53 is made of an elastic body and has a coil spring shape in the figure. However, when the material is made of metal, the contact portion is electrically conductive so as not to damage the reticle when contacting the reticle. A protective member such as resin or conductive rubber may be provided. The entire ground 53 may be made of a conductive resin or conductive rubber.

In the original transport apparatus according to the present invention, when the reticle 23 is received from the reticle stage 1 or another station, the ground 53 comes into contact with the reticle 23 first, so that the reticle itself is for some reason. When charged, the light shielding pattern 33 is grounded, thereby causing a potential change around the circuit pattern and possibly causing electrostatic breakdown in or around the circuit pattern. As a countermeasure, it is effective to increase the surface resistance value of the earth 53 to some extent so as to reduce the static electricity leakage rate and the potential change rate around the circuit pattern. However, if the leakage rate is too slow, when the reticle 23 and the suction pad 52, which is the main object of the present invention, are separated, the leakage of the charge generated by the peeling charge cannot be sufficiently performed. The resistance value is desirably about 10 ⁻⁷ to 10 ⁻¹³ Ωcm.

    Further, when a shape having a sharp tip, such as the ground 53, is brought close to an object having a different potential, the electric field concentrates on the tip portion and it becomes easy to discharge. Therefore, as shown in FIGS. 52 may be first brought into contact with the reticle 23 to neutralize the charges of the reticle hand 15 for transport and the reticle 23 to some extent, and then the earth 53 may be brought into contact with the reticle 23. 12 to 14, 56 is an air cylinder for driving the earth 53, and 57 is an arm connecting the air cylinder 56 and the earth 53.

    Further, the delivery may be performed after controlling the charges of the reticle chuck 41 and the reticle hand 15 for conveyance to be the same potential in advance. As a method thereof, the reticle chuck 41 and the reticle hand 15 for conveyance may be grounded to the same ground, or the bodies of each other may be electrically connected in advance. It is also possible to measure such that one potential is measured and the other is controlled to have the same potential.

    Further, in the load lock and reticle storage unit for receiving the reticle from the outside, the ionizer is neutralized by providing the ionizer as described above, and the reticle itself is charged, so that the periphery of the circuit pattern when the reticle hand 15 comes into contact. This prevents the circuit pattern from being electrostatically damaged.

    Further, in this embodiment, the ground 53 is preferably provided in the vicinity of each of the four suction pads 52 so that static electricity does not conduct around the circuit pattern. The purpose of leaking the charge generated by the separation itself can be achieved even at one place.

    FIG. 9 shows an original conveying apparatus according to the second embodiment of the present invention, in which the ground 54 is formed in a leaf spring shape or a line shape. By making the ground 54 into a leaf spring shape or a linear shape, the contact pressure to the reticle can be controlled relatively freely, and the degree of freedom in selecting the material of the ground 54 is increased.

    In the case of this embodiment, as in the first embodiment, when the earth 54 is made of metal, it is desirable to provide a protective member on the contact surface with the reticle. You may make it comprise resin etc.

    FIGS. 10 and 11 show a purge station incorporated in a semiconductor exposure apparatus according to the third embodiment of the present invention, 27 is a vent hole provided in the pellicle support frame 25, and 28 is a foreign substance into the pellicle. A filter for preventing entry, 61 is an inert gas supply nozzle for supplying inert gas to the pellicle space, 62 is an exhaust nozzle for exhausting gas in the pellicle space, and 55 is a nozzle separated from the pellicle support frame 25 It is a ground that leaks static electricity generated when it is applied. FIG. 10 is a side view of the purge station and shows a state in which the nozzles 61 and 62 are in close contact with the pellicle support frame 25 and gas replacement in the pellicle space is performed. FIG. 11 is a view of the purge station observed from the lower surface, and shows a state where the nozzles 61 and 62 are separated from the pellicle support frame 25 and static electricity generated in the pellicle support frame 25 is removed by the ground 55.

    Since the pellicle support frame 25 is bonded to the reticle 23 with a flexible adhesive and is insulated from the reticle 23, the light shielding pattern 33 on the reticle is grounded by handling the reticle 23. Static electricity does not leak and remains on the pellicle support frame 25. Since the pellicle film or plate 26 has very high insulating properties, it is easy to be charged to a high potential and difficult to diffuse into the air. Therefore, static electricity remaining on the pellicle support frame 25 moves to the pellicle film 26 due to diffusion. In addition, there is a possibility that the pellicle film 26 is charged to a high potential because static electricity is induced by the electric field generated by the static electricity of the pellicle support frame 25. Therefore, according to the present invention, static electricity to the pellicle support frame 25 can be prevented, and electrostatic breakdown of the circuit pattern 31 can be prevented.

FIG. 15 shows an embodiment of an exposure stage in a semiconductor exposure apparatus using EUV light as a light source according to the fourth embodiment of the present invention.
In EUV exposure, since there is no material that transmits EUV light with high efficiency, reflection as an original plate having a pattern surface formed of a multilayer film as disclosed in Japanese Patent Publication No. 7-27198 (Patent Document 7). A mold mask is used. Therefore, in this embodiment, an upper surface adsorption type EUV stage will be described. In FIG. 15, 81 is an EUV stage, 82 is an electrostatic chuck for attracting and holding a mask during exposure, 83 is a top plate, 84 is a linear motor movable element, 85 is a linear motor stator, and 71 is a reflective mask.

In a high vacuum environment of about 10 ⁻⁴ to 10 ⁻⁵ Pa, which is an EUV exposure environment, it is impossible to hold a reticle by vacuum suction that has been conventionally used, and Coulomb generally used in vacuum apparatuses. The reticle is held by an electrostatic chuck using force and Johnson Rabeck force (hereinafter referred to as electrostatic force). In this case, in order to increase the holding force of the reticle, a conductive film may be formed on the chuck holding surface on the mask 71 as disclosed in JP-A-1-152727 (Patent Document 8). good.

    FIG. 16 is a schematic view of a reflective mask used for EUV exposure. 71 is a reflective mask, which is made of a material having a linear thermal expansion coefficient of 30 ppb / ° C. or less, and includes titanium-doped silica glass and Two-phase glass ceramics are listed as material candidates. Reference numeral 72 denotes a multilayer film, which is composed of a reflective layer having a multilayer film structure and an absorber that absorbs soft X-rays, and forms an exposure pattern. 73 is a conductive film.

    Next, with reference to FIGS. 17 to 19, peeling charging between the EUV stage 81 and the reflective mask 71 when the mask as an original is transferred from the EUV stage 81 to the suction pad 52 on the transfer hand. The removal method will be described.

    FIG. 17 shows a state where the transfer hand 15 has moved below the EUV stage 81 in order to collect the mask 71, and the mask 71 is held by suction on the electrostatic chuck 82. In FIG. 17, reference numeral 91 denotes a ground for removing static electricity, and is configured on the transport hand 15. Reference numeral 92 denotes a lever for biasing the ground 91 upward, and a base portion thereof is fixed on the reticle hand 15. The ground 91 is a conductive film 73 formed on the back surface of the mask 71 by the pushing end of the lever 92. Is kept in a non-contact state.

    FIG. 18 shows a state in which the transport hand 15 is raised and the suction pad 52 is in contact with the mask 71. The suction pad 52 holds the mask 71 by electrostatic force in the same manner as the electrostatic chuck 82. As the conveyance hand 15 is raised, the pressure receiving end of the lever 92 first contacts the mask 71 before the suction pad 52, and the lever 92 is pushed downward. When the lever 92 is pushed downward, the bias of the ground 91 is released and the ground 91 contacts the conductive film 73.

    FIG. 19 is a view showing a state in which the transport hand 15 is lowered and the mask 71 is delivered from the electrostatic chuck 82 to the transport hand 15. When the mask 71 is peeled off from the electrostatic chuck 82, the charge is peeled off. By removing the static electricity generated by the ground by the ground 91, it is possible to prevent the static electricity from being accumulated in the mask 71. When the mask 71 is detached from the electrostatic chuck 82, a method of reducing the residual charge on the substrate by applying a reverse bias voltage or the like is employed, but it is not possible to completely remove the charge by itself. Even if there is a method for completely removing the residual charge by the electrostatic chuck, it is impossible to prevent the peeling charge, and according to this proposal, the residual charge on the mask 71 is also generated by the peeling charge. The charge can also be removed almost completely.

In addition, when an abrupt potential change is generated on the back surface of the mask, there is a possibility that the potential change of the pattern surface is induced to cause pattern destruction. In order to control the charge leakage speed, the ground 91 is 10 ⁻⁷ to It is desirable to have a surface resistance value of about 10 ⁻¹³ Ωcm.

    In this embodiment, the mask 71 is held by the transfer hand 15 by electrostatic force. However, a material having a high frictional resistance may be selected as the pad material, and the mask 71 may be held only by friction. Further, it may be clamped and held by providing a driving mechanism, or a mask outer periphery may be dropped to prevent a shift during conveyance.

(Example of device production method)
Next, an embodiment of a device production method using the device manufacturing apparatus described above will be described.
FIG. 20 shows a manufacturing flow of a microdevice (a semiconductor chip such as an IC or LSI, a liquid crystal panel, a CCD, a thin film magnetic head, a micromachine, etc.). In step 1 (circuit design), a device pattern is designed. In step 2 (mask production), a mask on which the designed pattern is formed is produced. On the other hand, in step 3 (wafer manufacture), a wafer is manufactured using a material such as silicon or glass. Step 4 (wafer process) is called a pre-process, and an actual circuit is formed on the wafer by lithography using the prepared mask and wafer. The next step 5 (assembly) is referred to as a post-process, and is a process for forming a semiconductor chip using the wafer produced in step 4, such as an assembly process (dicing, bonding), a packaging process (chip encapsulation), and the like. including. In step 6 (inspection), inspections such as an operation confirmation test and a durability test of the semiconductor device manufactured in step 5 are performed. Through these steps, the semiconductor device is completed and shipped (step 7).

  FIG. 21 shows a detailed flow of the wafer process. In step 11 (oxidation), the wafer surface is oxidized. In step 12 (CVD), an insulating film is formed on the wafer surface. In step 13 (electrode formation), an electrode is formed on the wafer by vapor deposition. In step 14 (ion implantation), ions are implanted into the wafer. In step 15 (resist process), a photosensitive agent is applied to the wafer. In step 16 (exposure), the circuit pattern of the mask is printed onto the wafer by exposure using an exposure apparatus which is one of the device manufacturing apparatuses described above. In step 17 (development), the exposed wafer is developed. In step 18 (etching), portions other than the developed resist image are removed. In step 19 (resist stripping), unnecessary resist after etching is removed. By repeating these steps, multiple circuit patterns are formed on the wafer.

  By using the production method of this embodiment, a highly integrated device that has been difficult to manufacture can be manufactured at low cost.

It is the schematic (side view) of the negative | original plate conveying apparatus which has earth | ground in 1st Example of this invention. It is the schematic of the reticle with which the pellicle was affixed. It is the schematic of the pattern area | region formed on the reticle. It is the schematic of a reticle scanning stage. It is a schematic block diagram which shows the reticle conveyance path | route especially of the semiconductor exposure apparatus in this invention. It is the schematic (front cross section) showing the state in which the reticle hand for conveyance of the negative plate conveying apparatus which has earth | ground in the 1st Example of this invention is supporting the reticle. It is the schematic (front cross section) showing the state which the reticle hand for conveyance of the negative | original plate conveying apparatus which has a ground in the 1st Example of this invention delivered the reticle to the reticle stage. It is the schematic (front cross section) showing the state in which the ground provided on the reticle hand for conveyance of the negative plate conveying apparatus having the ground in the first embodiment of the present invention was separated from the reticle. It is the schematic (side view) of the original conveying apparatus which has earth | ground in the 2nd Example of this invention. It is the schematic (front cross section) of the pellicle space purge station which has a mechanism which supplies an inert gas to a pellicle in the 3rd Example of this invention. It is the schematic (bottom view) of the pellicle space purge station which has a mechanism which supplies an inert gas to a pellicle in the 3rd Example of this invention. It is the schematic (side view) showing the state before the hand for conveyance of the negative | original plate conveying apparatus which has a ground in the 1st Example of this invention receives a reticle. It is the schematic (side view) showing the state in which the reticle hand for conveyance of the original-plate conveyance apparatus which has an earth | ground in 1st Example of this invention hold | maintained the reticle. It is the schematic (side view) showing the state in which the reticle hand for conveyance of the negative plate conveying apparatus having the ground held the reticle and brought into contact with the ground in the first embodiment of the present invention. It is the schematic of the EUV stage in the 4th Example of this invention. It is the schematic of the reflection type mask in the 4th Example of this invention. It is the schematic (side view) showing the state before the conveyance hand of the negative | original plate conveying apparatus which has a ground in the 4th Example of this invention receives a reticle. It is the schematic (side view) showing the state which the hand for conveyance of the negative | original plate conveying apparatus which has earth | ground in the 4th Example of this invention hold | maintains the reticle, and contacted earth | ground. It is the schematic (side view) showing the state which the reticle hand for conveyance of the negative plate conveying apparatus which has earth | ground in the 4th Example of this invention received the reticle. It is a figure which shows the flow of manufacture of a microdevice. It is a figure which shows the detailed flow of the wafer process in FIG.

Explanation of symbols

1 Reticle stage
DESCRIPTION OF SYMBOLS 2 Projection optical system 3 Environmental chamber 4 Air conditioner 8 Case 13 Reticle load lock 14 SMIF pod 15,16 Reticle hand 18 Reticle storage shelf 19 Pellicle inspection apparatus 23 Reticle 24 Pellicle 25 Pellicle support frame 26 Pellicle film or pellicle plate 27 Ventilation hole 28 Filter 31 Circuit pattern 32 Scribe line 33 Light-shielding pattern 34 Alignment mark 41 Reticle chuck 42 Top plate 43 Linear motor movable element 44 Linear motor stator 45 Air pad 46 Stage surface plate 51 Fork part 52 Suction pad 53, 54, 55 Earth 56 Actuator 57 Arm 61 Gas supply nozzle 62 Gas discharge nozzle 71 Reflective mask 72 Multilayer film 73 Conductive film 81 EUV stage 82 Electrostatic chuck 83 Top plate 84 Linear Over data mover 85 linear motor stator 91 ground 92 lever

Claims (14)

  In an original conveying apparatus for conveying an original used for semiconductor exposure, the apparatus includes a conveying unit that supports the original and conveys the original to a predetermined place, and an earth that releases charges charged on the original, and the earth is on the conveying means. An original conveying apparatus characterized by being configured as described above.   2. The original transport apparatus according to claim 1, wherein a contact area of the earth with the original plate is extremely smaller than a contact area between a support member supporting the original plate in advance and the original plate.   The original transport apparatus according to claim 1, wherein the ground releases electric charges generated by contact peeling between the support member and the original.   The original transport apparatus according to claim 3, wherein the ground is grounded through an electric resistance.   The original transportation device according to any one of claims 1 to 4, wherein a contact portion between the ground and the original plate is provided in the vicinity of a contact portion between the support member and the original plate.   6. The original transport apparatus according to claim 1, wherein at least a part of the ground is made of an elastic member.   In a semiconductor exposure apparatus that performs exposure using an original plate with a pellicle, a gas supply nozzle that closely adheres to a vent hole provided in the pellicle support frame and supplies gas to the pellicle space, and a ground that releases static electricity charged on the pellicle support frame A semiconductor exposure apparatus characterized in that the ground discharges static electricity generated by contact peeling between the original and the gas supply nozzle.   8. The semiconductor exposure apparatus according to claim 7, wherein the ground is provided on the gas supply nozzle and moves integrally with the gas supply nozzle.   In a semiconductor exposure apparatus that performs exposure using an original plate with a pellicle, a gas supply nozzle that is in close contact with a vent hole provided in a pellicle support frame and supplies gas to the pellicle space; and a gas discharge nozzle that discharges gas from the pellicle space; A semiconductor exposure apparatus comprising: a ground for discharging static electricity charged on the pellicle support frame, wherein the ground releases static electricity generated by contact peeling between the original plate and the gas supply nozzle and gas discharge nozzle.   The ground is provided on at least one of the gas supply nozzle and the gas discharge nozzle and moves integrally with either the gas supply nozzle or the gas discharge nozzle. The semiconductor exposure apparatus described in 1.   11. The semiconductor exposure apparatus according to claim 7, wherein the ground is grounded through an electric resistance.   The semiconductor exposure apparatus according to claim 7, wherein a contact area of the ground with the pellicle support frame is extremely smaller than a contact area between the nozzle and the pellicle support frame.   The semiconductor exposure apparatus according to claim 7, wherein at least a part of the ground is made of an elastic member.   A device manufacturing method, wherein a device is manufactured using the semiconductor exposure apparatus according to claim 7.