JP4444743B2 - Exposure apparatus and device manufacturing method - Google Patents

Description

  The present invention generally relates to an exposure apparatus that exposes a substrate, and more particularly, for example, a circuit pattern formed on a reticle is exposed on a wafer using a liquid immersion method, and a semiconductor device such as an IC or LSI, an imaging device such as a CCD, The present invention relates to an immersion type projection exposure apparatus for manufacturing various devices such as a display device such as a liquid crystal panel and a detection device such as a magnetic head. The present invention is particularly suitable for protecting the optical surface of an optical element used in the projection optical system of the exposure apparatus.

In recent years, with increasing density and speed of semiconductor integrated circuits, the pattern size of integrated circuits has been further reduced, and higher performance has been required for semiconductor manufacturing methods. In particular, improvement of the resolution in pattern transfer onto a wafer is regarded as the most important, and research and development of various transfer systems is underway. In general, the resolving power (resolution limit) R of the projection optical system is expressed by Rayleigh's equation: R = k1 × λ / NA (1)
It is represented by Here, λ is the wavelength of the exposure light, NA is the numerical aperture of the projection optical system, and k1 is a coefficient relating to the process. As can be seen from equation (1), in order to improve the resolving power, an optical system having a large numerical aperture that uses light having a shorter wavelength as exposure light is designed, and as a result, a phase shift mask, modified illumination, etc. A method such as reducing the coefficient can be considered.

On the other hand, it is conventionally known that the wavelength of exposure light can be substantially shortened by a technique called an immersion method. In the immersion type projection exposure using the principle of immersion, the optical path space facing the final optical element of the projection optical system and the wafer surface has a higher refractive index than air instead of air (here, the refractive index is n). ) By exposing in a state filled with liquid, the exposure wavelength is substantially reduced to 1 / n. From the above equation (1), the resolution limit can be 1 / n times that in the case where exposure is performed using the same exposure wavelength in the atmosphere. Moreover, the depth of focus becomes n times larger. Furthermore, the immersion type projection exposure apparatus does not require large changes in the light source and reticle, and the use of the existing product can be expected (improved), and has attracted attention as a practical means for improving resolution.
As an embodiment of this liquid immersion type projection exposure apparatus, the entire wafer including the wafer chuck is immersed in the liquid immersion agent filled in the water tank, the final lens of the projection optical system and the wafer surface of the portion facing it. There has been proposed one in which only the interval is locally filled with an immersion agent. For example, Patent Document 1 discloses a step-and-repeat type or step-and-scan type exposure apparatus that fills and exposes only the gap between the wafer surface and the final lens of the projection optical system facing the wafer. . In addition, the arrangement of the supply / recovery piping for the immersion agent, the supply direction of the immersion agent during the exposure process, the flow rate, and the like are also disclosed. Further, in the embodiment of Patent Document 1, when the surface of the optical element that comes into contact with the liquid is contaminated due to adhesion of impurities in the liquid, it is necessary to periodically replace the optical element, the cost. In addition, it is described that the optical element to be replaced is a parallel flat plate from the viewpoint of replacement time, that pure water can be used as an immersion agent, and that the lens surface can be cleaned with pure water.
International Publication No. WO99 / 49504 Pamphlet

However, even if the replacement work is easy or the work cost is not high, it is inevitable that the operation efficiency and schedule adjustment of the production line including the exposure apparatus will be affected when the optical element is replaced. In addition, the periodic replacement may cause variations in transfer accuracy depending on the actual degree of contamination. Furthermore, if a means for detecting the degree of contamination is additionally provided as a countermeasure against the transfer accuracy variation, the apparatus configuration becomes complicated and the cost increases. Even if the immersion agent has a cleaning action, after exposure processing (after completion of facing the wafer), if the immersion agent is left attached to the lens surface, water marks will form on the lens surface when the attached immersion agent evaporates. In other words, the surrounding substances are likely to be newly attached as contamination, which adversely affects the optical characteristics of the projection optical system and causes deterioration of the transfer pattern accuracy.
The present invention has been made in view of the above circumstances, and provides an immersion exposure apparatus that prevents deterioration of optical characteristics due to adhesion of dirt to the optical element surface of a projection optical system and performs good projection exposure. For illustrative purposes. It is another exemplary object of the present invention to provide an immersion exposure apparatus that removes the dirt to recover the optical characteristics and performs good projection exposure even if dirt is attached to the surface of the optical element. .

An exposure apparatus according to one aspect of the present invention includes an illumination optical system that illuminates a reticle with light from a light source, and a projection optical system that projects a pattern of the reticle onto a substrate, and is the most substrate of the projection optical system An exposure apparatus that exposes the substrate with the pattern via an immersion agent filled in a gap between the optical element disposed in the vicinity and the substrate, the optical surface protecting the optical surface of the optical element a protective member, the protective member detaching mechanism for attaching and detaching the optical surface protective member to the projection optical system, possess a substrate driving system for driving the substrate, by reserving a protective liquid to the optical surface protective member The optical surface can be immersed in the protective liquid, a supply path for supplying the protective liquid to the optical surface protection member, and a recovery path for recovering the supplied protective liquid are the substrate drive It is provided to the system And wherein the door.

The exposure apparatus, optical science surface protective member may be detachably coupled to the protective member detaching mechanism. You may have the immersion agent removal mechanism which removes the immersion agent adhering to the optical surface of an optical element . Protection for liquid may be a detergent different components and liquid infusion.

The exposure apparatus has a selection means for selecting whether to immerse the optical surface in the protective liquid stored in the optical surface protection member or to remove the immersion agent attached to the optical surface by the immersion agent removal mechanism. Also good. Substrate in protective liquid stored in the optical surface protective member may be capable immersion. The liquid of at least two kinds of supply paths supplied liquid switching means may be provided for feeding.

A device manufacturing method according to another aspect of the present invention includes a step of exposing a pattern to the substrate by the exposure apparatus and a step of performing an optical surface protection process on the exposed substrate.

  Other objects and further features of the present invention will be made clear by embodiments described below with reference to the accompanying drawings.

According to the present invention, since the tip including the final optical element surface (optical surface) of the projection optical system can be covered, it can be isolated from the surrounding atmosphere, so that it is possible to prevent dirt from adhering to the final optical element surface. Can do .

[Embodiment 1]
FIG. 2 is a schematic block diagram of an immersion type projection exposure apparatus (hereinafter referred to as an immersion exposure apparatus) as an exposure apparatus according to Embodiment 1 of the present invention. The liquid immersion exposure apparatus main body 1 is entirely covered with a chamber 2 to maintain a constant atmosphere inside the apparatus. The gantry 3 has a highly rigid structure, and enables highly accurate positioning of the wafer (substrate) 20 and the reticle 10. The reticle 10 is conveyed and held from outside the apparatus to a reticle stage (reticle drive system) 11 by a reticle conveyance system (not shown). The wafer 20 whose surface has been coated with a photosensitive resist is also transferred from the outside of the apparatus to the wafer chuck 21 on the wafer stage 22 and held by a wafer transfer system (not shown). The wafer stage 22 and the wafer chuck 21 constitute a substrate driving system.

The exposure light 5 is irradiated onto the reticle 10 by an illumination system 4 configured to include an ArF excimer laser (λ = 193 nm) light source and an illumination optical system. The exposure light 5 applied to the reticle 10 based on a control command from the light source control unit 43 forms an image on the surface of the wafer 20 via the projection optical system 6 to expose the resist. Of course, the light source is not limited to the ArF excimer laser, and a KrF laser (λ = 248 nm) or an F ₂ laser (λ = 157 nm) may be used.

The reticle stage 11 is attached to the gantry 3 and can be driven in the X direction, and moves based on a control command from the R stage position control unit 42. Wafer stage 22, X, Y, Z directions and rotation directions of each axis (ωx, ωy, ωz) Ru drivable der to. Thus, a desired area of the wafer 20 held on the wafer chuck 21 is moved directly below the projection optical system 6 or the posture of the wafer 20 is corrected based on a control command from the W stage position control unit 41. The reticle stage 11 and the wafer stage 22 can be detected and controlled by a reticle side laser interferometer 12 and a wafer side laser interferometer 23 (a laser interferometer in the Y direction is not shown), respectively. Furthermore, high-precision scanning exposure is possible even in a so-called scan exposure method in which pattern transfer is performed while simultaneously scanning and moving the reticle 10 and the wafer 20.

  At the time of exposure, the gap between the final optical element 7 and the surface of the wafer 20 facing the surface is filled with the immersion agent 24 supplied from the supply / discharge nozzle 25. For example, pure water is used as the immersion agent 24, and the gap size is about 100 μm. The immersion agent 24 and the gap are not limited to this. Here, the final optical element 7 is an optical element closest to the wafer 20 (that is, facing the wafer 20) among the optical elements provided in the projection optical system 6. For example, in the present embodiment, the final lens is used. That is. The gap dimension refers to the distance between the final lens 7 and the surface of the wafer 20.

A plurality of supply / discharge nozzles 25 are arranged around the tip of the projection optical system. Although two supply / discharge nozzles 25 are illustrated in FIG. 2, the number is not limited to this. Each supply / discharge nozzle 25 has a structure for both supplying and collecting the immersion agent 24 to the surface of the wafer 20 . Under the management of the immersion agent supply / discharge control unit 44, switching of supply, recovery or stop and control of the supply / discharge amount of the immersion agent 24 are performed in accordance with conditions such as the wafer stage driving direction during exposure.

FIG. 3 is a partially enlarged view showing the vicinity of the projection optical system 6 and the wafer 20 of the exposure apparatus during exposure. A gap between the projection optical system 6 and the wafer 20 is filled with an immersion agent 24.

When scanning exposure is performed by driving the wafer stage 22 (see FIG. 1) in the direction indicated by the arrow D1, the supply / discharge nozzle 25a supplies the immersion agent 24 to the wafer surface portion serving as an exposure region, and the supply / discharge nozzle 25b performs exposure. Control is made to recover immersion agent 24 on the wafer that is out of area. 2 denotes a lens cover (optical surface protection member) for covering the tip of the projection optical system 6 and isolating the final lens 7 from the ambient atmosphere in the exposure apparatus. Reference numeral 27 denotes the lens cover 26. It is the cover raising / lowering mechanism (protective member attaching / detaching mechanism) for the raising / lowering operation which raises / lowers .
FIG. 1 is a schematic block diagram of the vicinity of the lens cover 26 of the immersion exposure apparatus according to the first embodiment. The lens cover 26 can store a protective liquid 24a having substantially the same or the same components as the immersion agent 24, and is filled with the protective liquid 24a.

FIG. 1A shows a state during the exposure process. During the exposure process, the cover lifting mechanism 27 is lowered, and there is no possibility that the lens cover 26 and the tip of the projection optical system 6 interfere with each other. In this state, it is desirable that the lens cover 26 is not yet filled with the protective liquid 24a. In FIG. 1B, the tip of the projection optical system 6 is attached to the lens cover 26 for the purpose of preventing water marks and dust from adhering to the lens surface due to the evaporation of the immersion agent 24 adhering to the surface of the final lens 7. The state covered with is shown.
A procedure from FIG. 1A to FIG. 1B will be described. After the exposure of the wafer 20 is completed, the wafer 20 is removed from the wafer chuck 21 and collected, and the wafer stage 22 is driven so that the lens cover 26 is directly under the projection optical system 6. Next, the cover raising / lowering mechanism 27 is raised upward, that is, in the Z direction so as to approach the projection optical system 6, and the surface of the final lens 7 is immersed in the protective liquid 24a in the lens cover 26 (this state is projected by the lens cover 26). It is said that it was attached to the optical system 6). Here, when the protection liquid 24 a is not filled in the lens cover 26, the immersion liquid 24 is removed from the supply / discharge nozzle 25 disposed around the projection optical system 6 while the cover lifting mechanism 27 is being lifted. 24a is supplied so that the optical surface can be immersed . When removing the lens cover 26 from the final lens 7, it is desirable to collect the protective liquid 24 a in the lens cover 26 by the supply / discharge nozzle 25. By collecting the protective liquid 24a, there is no possibility that the protective liquid 24a may spill out of the lens cover 26 and scatter around when the wafer stage 22 is driven during exposure.

  As a case where the final lens 7 of the projection optical system 6 is covered with the lens cover 26, when the exposure processing instructed in lot units for the plurality of wafers 20 is completed, that is, after the exposure apparatus transitions to a so-called idle state. May be done automatically. Further, when a state where the exposure should be interrupted temporarily occurs during the exposure process, if there is a cover instruction from the operator, or if an interruption over a predetermined time is detected based on a command from the main control unit 40 May automatically cover.

[Embodiment 2]
FIG. 4 is a schematic configuration diagram in the vicinity of the lens cover 26 of the immersion exposure apparatus according to the second embodiment of the present invention. The second embodiment is different from the first embodiment in that the lens cover 26 can be separated from the cover lifting mechanism 27 in a state where the lens cover 26 covers the final lens 7. The cover coupling hook 32 is for coupling the lens cover 26 to the cover lifting mechanism 27 or the projection optical system 6. FIG. 4A shows a state during the exposure process, and the cover coupling hook 32 couples the lens cover 26 to the cover lifting mechanism 27. FIG. 4B shows a process of covering the final lens 7 with the lens cover 26 during non-exposure. After the exposure is completed, the wafer 20 is removed from the wafer chuck 21 and collected, and the wafer stage 22 is driven so that the lens cover 26 is directly below the projection optical system 6. Next, the cover elevating mechanism 27 is raised upward, that is, in the Z direction so as to approach the projection optical system 6, and the surface of the final lens 7 is immersed in the protective liquid 24 a in the lens cover 26. Here, when the protective liquid 24 a is not filled in the lens cover 26, the supply / discharge nozzle 25 disposed around the projection optical system 6 in the middle of the raising of the cover elevating mechanism 27 as in the first embodiment. The immersion liquid 24 is supplied as a protective liquid 24a.

  The lens cover 26 is coupled to the projection optical system 6 by driving the cover coupling hook 32 in the direction of the arrow D2 with the lens cover 26 covering the final lens 7, and then the cover lifting mechanism 27 is lowered to lower the lens cover 26. And the cover elevating mechanism 27 are separated. In the first embodiment, since the lens cover 26 is coupled to the wafer stage 22 via the cover lifting mechanism 27, the wafer stage 22 cannot be driven with the final lens 7 covered with the lens cover 26. It was. Therefore, the final lens 7 cannot be protected by the lens cover 26 during the maintenance process in which the exposure light is not irradiated, that is, the projection optical function is not used but the wafer stage 22 is moved.

  In the second embodiment, the wafer stage 22 can be driven without interfering with the wafer chuck 21 and the like even when the lens cover 26 is attached to the final lens 7 as shown in FIG. 4C. Since the maintenance process as described above can be performed in a state where the final lens 7 is protected by the lens cover 26, the possibility of contamination on the lens surface can be further reduced.

At the start of the exposure process, the wafer stage 22 is driven in the reverse procedure as described above, that is, so that the cover lifting mechanism 27 on the wafer stage 22 is directly below the projection optical system 6 to which the lens cover 26 is attached . Then, the protective liquid 24a in the lens cover 26 is collected to raise the cover lifting mechanism 27, and the cover coupling hook 32 is driven in the direction opposite to the arrow D2 to remove the lens cover 26 from the projection optical system 6. The recovery of the protective liquid 24a can also be performed in parallel with the driving operation of the wafer stage 22 and the subsequent lifting operation of the cover lifting mechanism 27, thereby further reducing the processing time. Can do.

[Embodiment 3]
In the first and second embodiments, the final lens 7 is immersed in the protective liquid 24a in the lens cover 26 to prevent dirt and the like from adhering to the surface of the final lens 7, but the embodiment of the present invention. In the immersion exposure apparatus according to No. 3, the immersion agent 24 adhering to the surface of the final lens 7 and causing water marks and dust is positively removed, and the lens surface is isolated from the ambient atmosphere in a dry state (see FIG. See 5).

In FIG. 5A, the roller 28 is disposed on the side surface of the lens cover 26. The roller 28 functions as an immersion agent removing mechanism on the surface of the final lens 7 at the tip of the projection optical system 6 and wipes the immersion agent 24 attached to the surface of the final lens 7. FIG. 5B shows a process of covering the final lens 7 with the lens cover 26 during non-exposure. After the exposure is completed, the wafer 20 is removed from the wafer chuck 21 and collected, and the wafer stage 22 is driven so that the lens cover 26 is directly below the projection optical system 6. During the driving, the roller 28 moves relative to the position 28 ″ (see FIG. 5C) while being in contact with the surface of the final lens 7, thereby cleaning the surface of the final lens 7. After cleaning, the lens cover 26 is moved to a position directly below the projection optical system 6, the cover lifting mechanism 27 is raised, and the final lens 7 is covered with the lens cover 26.

In the third embodiment, the roller 28 functioning as an immersion agent removing mechanism is directly brought into contact with the surface of the final lens 7 for wiping . However, those in the not name, of course is not limited to this. For example , air may be blown onto the surface of the final lens 7 by the air blow nozzle 28a that functions as an immersion agent removing mechanism, whereby the immersion agent 24 on the surface of the final lens 7 may be scattered and removed without contact. .

[Embodiment 4]
FIG. 6 is a schematic block diagram of the vicinity of the lens cover 26 of the immersion exposure apparatus according to the fourth embodiment of the present invention. In the fourth embodiment, the supply path 29 for supplying the protective liquid 24a into the lens cover 26 and the recovery path 30 for recovering the protective liquid 24a from the lens cover 26 to the lens cover 26 and the cover lifting mechanism 27 side. And are provided.

  Even when the projection optical system 6 is not located directly above the lens cover 26, supply and recovery of the protective liquid 24a into the lens cover 26 can be controlled. Since the attachment / detachment control of the lens cover 26 to the final lens 7 (that is, the drive control of the wafer stage 22) and the supply / recovery control of the protective liquid 24a into the lens cover 26 can be performed separately and independently. It is possible to shorten the time.

Further, as shown in FIG. 6, the surface of the final lens 7 may be cleaned by flowing the protective liquid 24a while controlling the flow rate of the supply path 29 and the recovery path 30 with the final lens 7 covered with a lens cover. Is possible. Also in the first embodiment, it is possible to clean the surface of the final lens 7 by controlling the flow rate of the supply / discharge nozzle 25 with the lens cover 26 attached (see FIG. 1B). However, in the fourth embodiment, supply liquid switching means for supplying two types of liquid from the supply path is provided. As a result, a cleaning agent having a high cleaning effect of components different from the immersion agent 24 can be caused to flow through the supply path 29 and the recovery path 30. Accordingly, a high cleaning effect can be obtained, and the cleaning agent does not have to flow through the supply / discharge nozzle 25, so that the supply / discharge nozzle 25 is not clogged with the cleaning agent .

After cleaning the final lens 7, the cleaning agent in the lens cover 26 is recovered through the recovery path 30, and the immersion agent 24 as the protective liquid 24 a is supplied from the supply / discharge nozzle 25, so that the surface of the final lens 7 is immersed in the immersion agent 24. It is possible to protect. Further, both the cleaning agent and the immersion agent 24 as the protective liquid 24a can be supplied from the supply passage 29, and the supply of the immersion agent 24 is supplied from the supply / discharge nozzle 25 by controlling the supply by switching. The surface of the final lens 7 can be cleaned and protected without necessity.

In the fourth embodiment, as shown in FIG. 6, the immersion exposure apparatus includes a supply path 29 and a recovery path 30 separately. Of course , the supply and recovery of the cleaning agent are performed by one flow path. It is also possible to configure so that In this case, for example, the surface of the final lens 7 is cleaned by performing control such that the supply operation and the recovery operation of the cleaning agent are sequentially repeated. The final lens 7 is cleaned every time the lens cover 26 is attached to the final lens 7, or a cleaning function for performing a cleaning operation as a maintenance command is prepared in advance. A case where cleaning is performed based on the above is considered.

[Embodiment 5]
FIG. 7 is a schematic block diagram of the vicinity of the lens cover of the immersion exposure apparatus according to Embodiment 5 of the present invention. The immersion exposure apparatus includes a roller 28 as an immersion agent removing mechanism and a supply path 29 and a recovery path 30 provided on the cover lifting mechanism 27 side (that is, the wafer stage 22 side). When the cover 26 is attached, the selection means can select whether the surface of the final lens 7 is immersed in the protective liquid 24a or in a dry state. Of course, the supply path 29 and the recovery path 30 are not essential, and the protective liquid 24a may be supplied from the supply / discharge nozzle 25 into the lens cover 26 as in the first embodiment.

When a series of exposure processes in units of lots is completed, the immersion exposure apparatus enters an idle state, covers the surface of the final lens 7 with the lens cover 26, and isolates the surface of the final lens 7 from the ambient atmosphere. In this case, for example, when the exposure process of the next lot is scheduled immediately, holding one state to the final lens 7 surface immersed in a protective liquid 24a filled with protective liquid 24a in the lens cover 26. When the next lot exposure process is not scheduled immediately or when the apparatus is stopped, the immersion agent 24 on the surface of the final lens 7 is removed by the roller 28 and covered with a dry lens cover 26.

[Embodiment 6]
In the first to fifth embodiments, the immersion agent 24 is locally filled between the surface of the wafer 20 facing the final lens 7 and the surface of the final lens 7, and the wafers 20 are sequentially placed in the filled region. It is an immersion exposure apparatus that performs exposure. On the other hand, as shown in FIG. 8, the immersion exposure apparatus according to the sixth embodiment fills an immersion agent 24 in a liquid tank 31 provided so as to surround the wafer holding surface of the wafer chuck 21 to obtain a wafer chuck. The entire wafer 20 held by the substrate 21 is immersed in the liquid immersion agent 24.

  According to the immersion exposure apparatus according to the sixth embodiment, the surface of the final lens 7 can be protected without providing a separate lens cover. That is, even after the wafer 20 is collected after the exposure is completed, the liquid tank 31 is filled with the liquid immersion agent 24, and the final lens 7 is immersed in the liquid immersion agent 24. Can be prevented. Since the liquid tank 31 also functions as a lens cover (optical surface protection member), a control process is performed so that the final lens 7 is immersed in the liquid immersion agent 24 in the liquid tank 31 at the time of non-exposure such as after exposure. Do. Here, at the time of exposure, supply and recovery of the immersion agent 24 are performed by the supply path 29 and the recovery path 30, and at the time of non-exposure, the immersion agent 24 in the liquid tank 31 is recovered, and the supply liquid is switched by the supply liquid switching means. It is also possible to supply the cleaning liquid from 29 into the liquid tank 31. Thereby, the cleaning effect of the surface of the final lens 7 can be improved, and contamination can be prevented from sticking to the lens surface.

[Embodiment 7]
Next, an embodiment of a device manufacturing method using the above-described immersion exposure apparatus will be described with reference to FIGS. FIG. 9 is a flowchart for explaining how to fabricate devices (ie, semiconductor chips such as IC and LSI, LCDs, CCDs, and the like). Here, the manufacture of a semiconductor chip will be described as an example. In step 101 (circuit design), a device circuit is designed. In step 102 (reticle fabrication), a reticle on which the designed circuit pattern is formed is fabricated. In step 103 (wafer manufacture), a wafer (substrate) is manufactured using a material such as silicon. Step 104 (wafer process) is called a pre-process, and an actual circuit is formed on the wafer by lithography using the reticle and wafer. Step 105 (assembly) is called a post-process, and is a process for forming a semiconductor chip using the wafer created in step 104, and includes processes such as an assembly process (dicing and bonding), a packaging process (chip encapsulation), and the like. . In step 106 (inspection), inspections such as an operation confirmation test and a durability test of the semiconductor device created in step 105 are performed. Through these steps, the semiconductor device is completed and shipped (step 107).

  FIG. 10 is a detailed flowchart of the wafer process in Step 104. In step 111 (oxidation), the wafer surface is oxidized. In step 112 (CVD), an insulating film is formed on the surface of the wafer. In step 113 (electrode formation), an electrode is formed on the wafer by vapor deposition or the like. In step 114 (ion implantation), ions are implanted into the wafer. In step 115 (resist process), a photosensitive agent is applied to the wafer. In step 116 (exposure), the circuit pattern of the reticle is exposed onto the wafer by an immersion exposure apparatus. In step 117 (development), the exposed wafer is developed. In step 118 (etching), portions other than the developed resist image are removed. In step 119 (resist stripping), the resist that has become unnecessary after the etching is removed. By repeatedly performing these steps, multiple circuit patterns are formed on the wafer. According to the manufacturing method of the present embodiment, it is possible to manufacture a high-quality and highly integrated device at a lower cost than in the past.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these, A various deformation | transformation and change are possible within the range of the summary.

It is a schematic block diagram which shows the lens cover vicinity of the immersion exposure apparatus which concerns on Embodiment 1 of this invention. It is a schematic block diagram which shows the whole structure of the immersion exposure apparatus which concerns on Embodiment 1 of this invention. FIG. 2 is a partially enlarged view showing an enlarged view of a projection optical system and the vicinity of a wafer during exposure by the immersion exposure apparatus shown in FIG. 1. It is a schematic block diagram which shows the lens cover vicinity of the immersion exposure apparatus which concerns on Embodiment 2 of this invention. It is a schematic block diagram which shows the lens cover vicinity of the immersion exposure apparatus which concerns on Embodiment 3 of this invention. It is a schematic block diagram which shows the lens cover vicinity of the immersion exposure apparatus which concerns on Embodiment 4 of this invention. It is a schematic block diagram which shows the lens cover vicinity of the immersion exposure apparatus which concerns on Embodiment 5 of this invention. It is a schematic block diagram which shows the lens cover vicinity of the immersion exposure apparatus which concerns on Embodiment 6 of this invention. 3 is a flowchart for explaining a device manufacturing method by the exposure apparatus shown in FIG. 10 is a detailed flowchart of step 104 shown in FIG. 9.

Explanation of symbols

1: Immersion exposure apparatus body 4: Illumination system 6: Projection optical system 7: Final optical element (final lens)
10: Reticle 11: Reticle stage (reticle drive system)
20: Wafer (substrate)
21: Wafer chuck (part of wafer drive system)
22: Wafer stage (part of wafer drive system)
24: immersion liquid 24a: protective liquid 25, 25a, 25b: supply / discharge nozzle 26: lens cover (optical surface protection member)
27: Cover lifting mechanism (protective member attaching / detaching mechanism)
28: Roller (immersion agent removal mechanism)
29: Supply path 30: Collection path 40: Main controller 41: W stage position controller 42: R stage position controller 43: Light source controller 44: Immersion agent supply / discharge controller

Claims (8)

An illumination optical system that illuminates the reticle with light from a light source;
A projection optical system for projecting the reticle pattern onto a substrate,
An exposure apparatus that exposes the substrate with the pattern via an immersion agent filled in a gap between the optical element disposed closest to the substrate of the projection optical system and the substrate,
An optical surface protection member for protecting the optical surface of the optical element;
A protective member attaching / detaching mechanism for attaching / detaching the optical surface protecting member to / from the projection optical system ;
Possess a substrate drive system that drives the substrate,
The optical surface can be immersed in the protective liquid by storing the protective liquid in the optical surface protective member,
An exposure apparatus , wherein a supply path for supplying the protection liquid to the optical surface protection member and a recovery path for recovering the supplied protection liquid are provided in the substrate drive system .   2. The exposure apparatus according to claim 1, wherein the optical surface protection member is detachably coupled to the protection member attaching / detaching mechanism.   The exposure apparatus according to claim 1, further comprising an immersion agent removing mechanism that removes the immersion agent attached to the optical surface of the optical element. The exposure apparatus according to claim 1 , wherein the protective liquid is a cleaning agent having a component different from that of the immersion agent. And a selection means for selecting whether to immerse the optical surface in the protective liquid stored in the optical surface protection member or to remove the immersion agent attached to the optical surface by an immersion agent removal mechanism. 4. An exposure apparatus according to claim 3 , wherein An apparatus according to claim 1, wherein the substrate is capable immersed in the protection liquid stored in the optical surface protective member. 2. The exposure apparatus according to claim 1 , further comprising supply liquid switching means for supplying at least two kinds of liquid from the supply path. A step of exposing a pattern to a substrate by the exposure apparatus according to any one of claims 1 to 7 ,
And a step of performing an optical surface protection process on the exposed substrate.