Shutter blade apparatus, shutter unit, image pickup apparatus, exposure apparatus, and method of manufacturing device

A shutter blade apparatus includes a shutter blade; a first pushing member including two first pushing portions configured to push a first surface of the shutter blade; and a second pushing member including a second pushing portion configured to push a second surface of the shutter blade, the second surface being opposite to the first surface. The second pushing portion is located between the two first pushing portions.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a shutter blade apparatus including a shutter blade that blocks and unblocks an opening, a shutter unit, an image pickup apparatus, an exposure apparatus, and a method of manufacturing a device using the exposure apparatus.

2. Description of the Related Art

In general, reduction projection exposure apparatuses and the like have been used for manufacturing semiconductor devices and the like. The reduction projection exposure apparatuses reduce the size of patterns formed on originals, such as reticles, using reduction projection lenses and project the reduced patterns onto substrates such as wafers. The pattern of a reticle is transferred to several tens of positions on a wafer by alternately repeating step driving of an XY stage and exposure. Recently, in order to improve the productivity of the exposure apparatuses, efforts have been made to reduce the cycle time during exposure by increasing the opening and closing speed or the like of shutters disposed on paths of exposure light. Moreover, in order to reduce the time required for exposure, the sensitivity of a resist applied to wafers or the like has been rapidly improved.

According to the above-described known technology, a shutter blade constituting a shutter in a light-source optical system that generates an exposure light beam is inserted into a path of the exposure light beam so as to block the light beam. Thus, the size of the shutter blade needs to be larger than the cross-section of the exposure light beam. Moreover, when the shutter is closed, the shutter blade absorbs the heat of the exposure light beam, and can be deformed or melted. Accordingly, the surface of the shutter blade in general has a mirror-like finish so as to reflect the exposure light beam. In addition, when the exposure light beam reflected by the shutter blade travels back to the light source, thermal fluctuations can be generated in the light source. Therefore, the shutter blade in general is obliquely inserted into the path of the exposure light beam such that the light beam reflected by the shutter blade does not travel back to the light source. With this arrangement, the cross-section of the light beam blocked by the shutter blade becomes elliptical.

Therefore, the size of the shutter blade needs to be still larger than the cross-section of the light beam perpendicular to the light path when only one shutter blade is used for blocking the light beam. On the other hand, the opening and closing speed of the shutter needs to be increased in order to improve the throughput of the exposure apparatus. Accordingly, the weight of the shutter blade needs to be reduced while the required cross-section of the shutter blade is maintained. To this end, the thickness of the shutter blade may be reduced by using a light and heat-resistant metallic material for the shutter blade. Some known technologies intend to reduce the weight of the shutter blade while the cross-section required for blocking the exposure light beam is maintained. Japanese Patent Laid-Open No. 11-233423, for example, describes a shutter for exposure facilitating an increase in the opening and closing speed.

The known technology will now be described with reference toFIGS. 7A and 7B. A shutter40formed of a pair of rotary shutter units40aand40bis disposed on a path of an exposure light beam100to which a wafer or the like is exposed. The rotary shutter units40aand40bare synchronously rotated by motors45aand45b, respectively. As shown inFIG. 7B, for example, the exposure light beam100is blocked or unblocked by the rotation of shutter blades41ato43aand shutter blades41bto43bof the rotary shutter units40aand40b, respectively. That is, the rotary shutter unit40apartially blocks the upper half or more of the exposure light beam100in a successive manner using the three shutter blades41ato43athat are obliquely inserted into the path of the exposure light beam100. Similarly, the rotary shutter unit40bpartially blocks the lower half or more of the exposure light beam100in a successive manner using the three shutter blades41bto43bthat are obliquely inserted into the path of the exposure light beam100.

The three shutter blades41ato43aand the three shutter blades41bto43bof the rotary shutter units40aand40b, respectively, form light-shielding portions each having a central angle of 60° disposed at intervals of 60° in a circumferential direction of rotating shafts44aand44b, respectively. The shutter blades41ato43aand the shutter blades41bto43bof the rotary shutter units40aand40b, respectively, are rotated in connection with the rotation of the rotating shafts44aand44bdriven by the motors45aand45b, respectively. The rotating positions of the shutter blades are detected by rotary encoders46aand46b. In the above-described known technology, the size of the shutter blades can be reduced as compared with the case where only one shutter blade is used for blocking the entire exposure light beam100. Accordingly, the moment of inertia of the shutter blades can be reduced, thereby facilitating an increase in the opening and closing speed of the shutter.

However, in the known technology described in Japanese Patent Laid-Open No. 11-233423, the rotary shutter units40aand40bneed to be synchronously rotated using the motors45aand45b, and a difference in velocity of approximately sub-milliseconds is generated by factors such as mechanical structures. Furthermore, in order to equalize the distribution of the amount of exposure light applied in the exposure area of the wafer, both edges of the shutter blades41ato43aand the shutter blades41bto43bshown inFIG. 7Bcrossing the exposure light beam100need to have the same shape. Thus, the difference in velocity between the shutter blades41ato43aand the shutter blades41bto43bcan exert detrimental effects on the distribution of the amount of exposure light in the above-described known technology.

On the other hand, only one shutter blade is used for blocking an exposure light beam while the thickness of the shutter blade is reduced such that the weight of the shutter blade is reduced in some technologies. However, the amount of light when the shutter is closed needs to be smaller than or equal to one-millionth of that when the shutter is fully opened. Therefore, in order to improve the blocking performance of the shutter, a shielding plate needs to be disposed in the vicinity of an opening that is to be blocked or unblocked by the shutter blade so as to be adjacent to the shutter blade. At this moment, when the stiffness of the shutter blade is reduced due to the low-profiled shutter blade, the shutter blade can be deformed by the weight thereof or a centrifugal force or the like during the rotation thereof, and can come into contact with the shielding plate. This can prevent normal operation of the shutter.

SUMMARY OF THE INVENTION

The present invention is directed to a shutter blade configured so as to be subjected to reduced deformation.

According to an aspect of the invention, a shutter blade apparatus includes a shutter blade, a first pushing member including two first pushing portions configured to push a first surface of the shutter blade, and a second pushing member including a second pushing portion configured to push a second surface of the shutter blade, the second surfaces being opposite the first surface. The second pushing portion is located between the two first pushing portions.

According to another aspect of the invention, a shutter unit includes the above-described shutter blade apparatus and a motor configured to rotate the shutter blade.

According to another aspect of the invention, an image pickup apparatus includes the above-described shutter blade apparatus and an image pickup element configured to receive light via the shutter blade apparatus.

According to another aspect of the invention, an exposure apparatus, exposing a substrate to light via a pattern formed on a retile, includes an illumination optical system configured to illuminate the reticle and the above-described shutter blade apparatus disposed in the illumination optical system.

According to another aspect of the invention, a method of manufacturing a device includes exposing a substrate to light using the above-described exposure apparatus, developing the exposed substrate, and producing the device by processing the developed substrate.

Further features and aspects of the present invention will become apparent from the following detailed description of exemplary embodiments with reference to the attached drawings. In the description, reference is made to accompanying drawings, which form apart thereof, and which illustrate an example of the invention. Such example, however, is not exhaustive of the various embodiments of the invention, and therefore reference is made to the claims which follow the description for determining the scope of the invention.

DESCRIPTION OF THE EMBODIMENTS

First Exemplary Embodiment

As shown inFIG. 1A, a shutter unit10includes a shutter blade apparatus according to a first exemplary embodiment of the present invention. InFIG. 1A, a −Z direction corresponds to a direction of gravity. The shutter blade apparatus according to the first exemplary embodiment includes shutter blades11,12, and13, a motor17having a rotary encoder18, and a boss15and a retaining plate16that attach the shutter blades11to13to a rotating shaft14of the motor17.

As shown inFIG. 1B, the shutter blades11,12, and13each have a fan shape, and are radially disposed at regular intervals. The shutter blades11,12, and13are integrated with each other at a disk-shaped central portion having a predetermined area. The shutter blades11,12, and13are held between the boss15and the retaining plate16so as to be attached to the rotating shaft14of the motor17that has the rotary encoder18for detecting the rotational position of the rotating shaft14. As shown inFIGS. 1A and 1B, the shutter blades11,12, and13are attached to the rotating shaft14by tightening bolts101that are screwed into both the boss15and the retaining plate16while the shutter blades11,12, and13are held between the boss15and the retaining plate16.

The boss15includes a first pushing member having protrusions15aand15bserving as first supporting portions (first pushing portions) extending in three directions from the outer periphery of the boss15, the first pushing member pushing first surfaces (i.e., surfaces facing the boss) of the shutter blades11to13at least two positions (seeFIG. 1B). The retaining plate16includes a second pushing member having protrusions16aserving as second supporting portions (second pushing portions) extending in three directions from the outer periphery of the retaining plate16, the second pushing member pushing second surfaces (surfaces opposite the first surfaces; surfaces facing the retaining plate) of the shutter blades11to13at at least one position (seeFIG. 1B). At least one of the protrusions16aserving as the second supporting portions is located between the protrusions15aand15bserving as the first supporting portions (seeFIG. 1D) so as to push and hold the shutter blades11to13between the protrusions15aand15band the protrusion16a. The first pushing member notionally indicates the boss15, and the second pushing member notionally indicates the retaining plate16.

As shown inFIG. 1A, the three shutter blades11to13are successively inserted into a light path2of an exposure light beam100so as to block the exposure light beam100. That is, the three shutter blades11,12, and13of the shutter unit10form light-shielding portions having a central angle of 60° disposed at intervals of 60° in the circumferential direction of the rotating shaft14so as to block the exposure light beam100. Space areas other than the light-shielding portions serving as substantial portions of the shutter blades11to13successively allow passage of the exposure light beam100without blocking the exposure light beam100.

As shown inFIG. 1C, the protrusions16aserving as the second supporting portions of the retaining plate16serving as the second pushing member are bent toward the second surfaces of the shutter blades11to13(toward the boss15) in advance. The pushing force with which end portions of the protrusions16abent toward the boss15push the shutter blades11,12, and13is increased as the bolts101are more securely tightened. Since the pairs of protrusions15aand15bfirmly support the pushing force of the end portions of the protrusions16a, the holding force of the protrusions15aand15band the protrusions16acan be increased. Among the first supporting portions and the second supporting portions, the second supporting portions, for example, can be formed of plate springs bent toward the boss15instead of the protrusions16a.

Next, operations of the shutter blade apparatus according to the first exemplary embodiment of the present invention used in the shutter unit10will be described. After tightening the bolts101while the shutter blades11,12, and13are interposed between the boss15and the retaining plate16, the shutter blades11,12, and13are attached to the rotating shaft14of the motor17. In this exemplary embodiment, the protrusions15aand15bof the boss15and the protrusions16aof the retaining plate16are arranged as shown inFIG. 1D. The protrusions16aof the retaining plate16are located at substantially intermediate positions between the protrusions15aand15bof the boss15so as to support the shutter blades11to13. Since the protrusions16aof the retaining plate16are bent so as to have predetermined dimensions as shown inFIG. 1C, the shutter blades11to13are pressed and forcedly deformed.

FIG. 1Eillustrates the shutter blade13when the shutter blade13is forcedly deformed. Herein, the shutter blade13is described as an example. The shutter blade13is forcedly deformed around the protrusion16aserving as a supporting point such that the end portions are lifted in a direction opposite to the direction in which the protrusions15aand15bprotrude (−G direction). As shown inFIG. 1E, end portions E and F of the shutter blade13are separated from a horizontal line in a direction opposite that of the pushing force of the protrusion16aas the positions of the end portions become closer to the ends (outer periphery) of the shutter blade13. With this forced deformation, deformation of the shutter blade13caused by the weight thereof can be substantially cancelled, and the stiffness thereof can also be increased. Thus, deformation of the shutter blade13during the rotation thereof can be minimized.

The stiffness of the shutter blades11,12, and13can be increased by applying the structure according to the first exemplary embodiment also to the shutter blade11and12. This leads to a reduction in thickness of the shutter blades11,12, and13. In the first exemplary embodiment, only the protrusion16aof the retaining plate16is bent in advance so as to have predetermined dimensions. However, the protrusions15aand15bof the boss15can also be bent toward the first surface of the shutter blade13so as to have predetermined dimensions. Herein, the bolts101have a function of adjusting the pushing forces with which the boss15and the retaining plate16push the first and second surfaces, respectively, of the shutter blades11to13.

According to the first exemplary embodiment of the present invention, the amount of forced deformation of the E and F portions (seeFIG. 1E) of the shutter blades11to13can be adjusted and controlled as appropriate by adjusting the tightening force of the bolts101. Therefore, the deformation of the shutter blades11to13caused by the weights thereof and by a centrifugal force or the like generated during the operation of the shutter unit10can be minimized even when thin and low-stiffness shutter blades11to13are used for higher speed. From this point of view, the shutter blades11to13can be made thinner and lighter, and the moment of inertia of the shutter blades11to13can be further reduced. With this, faster and more highly functional shutters can be realized. On the other hand, according to the shutter unit10in accordance with the first exemplary embodiment of the present invention, the amounts of forced deformation, the shapes, and the strengths of the shutter blades11to13can be desirably controlled by adjusting the bolts101even when the shutter blades11to13are made thinner (lighter) and are easily deformed. With this, the deformation of the shutter blades caused by the weights thereof and the deformation of the shutter blades caused by a centrifugal force or the like generated during the operation of the shutter unit can be minimized, thereby ensuring stable blocking and unblocking of an exposure aperture at high speed.

Second Exemplary Embodiment

Next, a second exemplary embodiment of the present invention will be described. InFIGS. 2A and 2B, the same reference numbers and symbols are used for the same components shown inFIGS. 1A to 1E, and the descriptions thereof will be omitted or simplified. In this exemplary embodiment, five protrusions serving as first and second supporting portions (described below) are provided for each of the shutter blades (light-shielding portions)11,12, and13as shown inFIGS. 2A and 2B. Since the structures of the shutter blades11,12, and13are the same in this exemplary embodiment, only the structure of the shutter blade13will be described as an example. In the second exemplary embodiment, a first pushing member notionally indicates a boss21, and a second pushing member notionally indicates a retaining plate22.

A first surface of the shutter blade13is supported by two protrusions21aand21bserving as the first supporting portions, having a space therebetween, of the boss21that is attached to the rotating shaft14. Moreover, a second surface of the shutter blade13is supported by three protrusions22a,22b, and22cserving as the second supporting portions, disposed at regular intervals, of the retaining plate22. That is, the protrusion21ais located at an intermediate position of the protrusions22aand22b(seeFIG. 2A) such that the shutter blade13is pressed and held by the protrusion21aand the protrusions22aand22b. In addition, the protrusion21bis located at an intermediate position of the protrusions22band22c(seeFIG. 2A) such that the shutter blade13is pressed and held between the protrusion21band the protrusions22band22c.

In this manner, the shutter blade13is pressed and held by the five protrusions21a,21b, and22ato22cdisposed at regular intervals such that the amount of forced deformation of the shutter blade13is maintained more stably by a more stable pushing force. Moreover, the protrusion22bof the retaining plate22is bent toward the second surface of the shutter blade13in advance as compared with the protrusions22aand22cso as to have predetermined dimensions. With this, the pushing force of the protrusion22bcan be increased. All the five protrusions21a,21b, and22ato22cor the protrusion22bof the retaining plate22bent toward the boss21can be formed of a plate spring as in the first exemplary embodiment.

Next, operations of a shutter blade apparatus according to the second exemplary embodiment of the present invention used in a shutter unit will be described. First, the retaining plate22is fixed to the boss21by tightening the bolts101while the shutter blades11,12, and13are interposed between the boss21and the retaining plate22. Since the protrusion22bof the retaining plate22is bent in advance so as to have predetermined dimensions, the shutter blade13is pushed by the protrusion22b, and forcedly deformed as shown inFIG. 2B. However, the amount of forced deformation of the shutter blades11,12, and13at both ends adjacent to the outer peripheries thereof can be regulated due to the protrusions22aand22cof the retaining plate22(seeFIG. 2B). In the first exemplary embodiment, the amount of deformation at the E and F portions shown inFIG. 1Eis increased as the thickness of the shutter blades11,12, and13is reduced. However, the speed of the shutter unit cannot be increased when air resistance occurs during the rotation of the shutter blades11,12, and13due to the deformation of the shutter blades11,12, and13.

Therefore, in the second exemplary embodiment, the amount of deformation of the shutter blades11,12, and13at the E and F portions shown inFIG. 1Eis regulated by arranging the protrusions22aand22cof the retaining plate22in the vicinity of the E and F portions. In the second exemplary embodiment, only the protrusion22bof the retaining plate22is bent in advance so as to have predetermined dimensions. However, the protrusions21aand21bof the boss21and the protrusions22aand22cof the retaining plate22can also be bent toward the first surface and the second surface, respectively, of the shutter blade13so as to have predetermined dimensions. Herein, the bolts101are used for adjusting the pushing forces with which the boss21and the retaining plate22push the first and second surfaces, respectively, of the shutter blades11,12, and13.

According to the second exemplary embodiment of the present invention, the amount of forced deformation of the E and F portions (seeFIG. 1E) of the shutter blades11to13can also be adjusted and controlled as appropriate by adjusting the tightening force of the bolts101. Therefore, the deformation of the shutter blades11to13caused by the weights thereof and by a centrifugal force or the like generated during the operation of the shutter unit10can be minimized even when thin and low-stiffness shutter blades11to13are used for higher speed. From this point of view, the shutter blades11to13can be made thinner and lighter, and the moment of inertia of the shutter blades11to13can be further reduced. With this, faster and more highly functional shutter units can be realized. In the second exemplary embodiment, in particular, the shutter blade13is pressed and held by the five protrusions21aand21b, and22ato22cdisposed at regular intervals such that the amount of forced deformation, the shape, and the strength of the shutter blade13are maintained more stably by a more stable pushing force. This can lead a more reliable shutter blade.

Third Exemplary Embodiment

Image Pickup Apparatus

Next, a third exemplary embodiment of the present invention will be described.

Structure of Image Pickup Apparatus

As shown inFIG. 3A, an image pickup apparatus in this exemplary embodiment includes an image taking lens51disposed along a light axis110, a television camera52including a rotary shutter, a bayonet mount53, and a filter54such as an optical low-pass filter and a near-infrared cut filter. Moreover, the image pickup apparatus includes an aperture plate55constituting a rotating body of the rotary shutter, a retaining plate56the holds the aperture plate55, and a supporting member57that supports the aperture plate55. Furthermore, the image pickup apparatus includes a photosensor58of the transmissive type and a rotary shutter unit59. In addition, the image pickup apparatus includes a color-separation prism60that supports a three-CCD system and image pickup elements61a,61b, and61c.

The rotary shutter unit59is formed of the aperture plate55, the retaining plate56, the supporting member57, and the photosensor58. The rotary shutter unit59is disposed such that the opening55acan be located between the image taking lens51and the color-separation prism60when the rotary shutter unit59is positioned at a predetermined rotational angle. A light beam output from the image taking lens51passes through an opening55aof the aperture plate55, and is received by at least one of the image pickup elements61a,61b, and61cvia the color-separation prism60. When an image pickup system of the television camera52is used for capturing images of a fast moving object, the rotary shutter unit59can supply intermittent instantaneous exposures to the image pickup element61band the like such that excellent images with reduced blur and distortion can be obtained.

The mass distribution of the aperture plate55may be uneven due to the opening55a, and the aperture plate55may wobble due to a centrifugal force during, in particular, high-speed rotation. This may exert detrimental effects on image pickup performance. In order to eliminate such concerns, protrusions57ato57eserving as first supporting portions of the supporting member57serving as a first pushing member are pressed toward a first surface of the aperture plate55as shown inFIGS. 3B and 3Cin the third exemplary embodiment. Moreover, protrusions56ato56fserving as second supporting portions of the retaining plate56serving as a second pushing member are pressed toward a second surface of the aperture plate55. The supporting member57and the retaining plate56hold the aperture plate55therebetween by tightening the bolts101.

That is, the protrusions57ato57eand the protrusions56ato56fare disposed in an alternating manner on either surface of the aperture plate55, and the aperture plate55is held by the protrusions by tightening the bolts101. At least end portions of the protrusions57ato57eof the supporting member57are bent toward the first surface of the aperture plate55in advance so as to forcedly deform the aperture plate55. Since the stiffness of the aperture plate55can be increased by the deformation, the deformation of the aperture plate55caused by a centrifugal force or the like generated during the rotation thereof can be minimized, and the wobbling of the aperture plate55during the rotation thereof can be reduced. Herein, the supporting member57and the retaining plate56can be, for example, disk-shaped members, and have the first and second supporting portions (protrusions), respectively, at the peripheries thereof. On the other hand, the protrusions57ato57eand the protrusions56ato56fcan be plate springs as appropriate.

In the rotary shutter unit59, the aperture plate55is rotated by energizing a motor62connected to a rotating body integrated with the aperture plate55via a belt63. Since the rotation of the aperture plate55needs to be synchronized with read signals of the image pickup element61aand the like, the number of revolutions of the aperture plate55is detected by the photosensor58. The photosensor58can be, for example, of the encoder type that reads light transmitting through a slit (not shown) of the aperture plate55. Herein, the bolts101have a function of adjusting the pushing forces with which the supporting member57and the retaining plate56push the first and second surfaces, respectively, of the aperture plate55.

In the image pickup apparatus according to the third exemplary embodiment of the present invention, the first supporting portions (protrusions57ato57e) and the second supporting portions (protrusions56ato56f) are pressed toward the aperture plate55. Thus, effects similar to those in the first exemplary embodiment can be produced. That is, even when the aperture plate55is made thinner (lighter) and is easily deformed, the amount of forced deformation and the shape of the aperture plate55can be desirably controlled such that the aperture plate55is not easily deformed. With this, the deformation by the weight and that caused by a centrifugal force or the like can be minimized in the image pickup apparatus according to the third exemplary embodiment. Thus, the exposure aperture (opening55a) of the aperture plate55can be stably blocked and unblocked at high speed. Therefore, the image pickup apparatus according to the third exemplary embodiment can produce excellent images with reduced blur and distortion due to improvements in rotational balance of the aperture plate55achieved by reducing the wobbling of the aperture plate55during the high-speed rotation thereof.

Fourth Exemplary Embodiment

Exposure Apparatus

Next, a fourth exemplary embodiment of the present invention will be described. InFIG. 4, the same reference numbers and symbols are used for the same components shown inFIGS. 1A to 1E, and the descriptions thereof will be omitted or simplified. As shown inFIG. 4, an exposure apparatus according to this exemplary embodiment includes a mercury lamp71serving as a light source, an elliptic mirror72that condenses an exposure light beam100emitted from the mercury lamp71, and a first lens73that converges the exposure light beam100. Moreover, the exposure apparatus includes a light-source optical system76including the shutter unit10used for exposure, a second lens74that collimates the light beam converged by the first lens73, and a half mirror75for extracting part of the exposure light beam100. Furthermore, the exposure apparatus includes a reticle stage77on which a reticle R is placed. The reticle R serves as an original having a pattern, the pattern being transferred onto a wafer W serving as an object to be exposed (substrate) during each shot.

In addition, the exposure apparatus according to this exemplary embodiment shown inFIG. 4includes a projection optical system79including a reduction projection lens78for projecting the reduced pattern of the reticle R onto the wafer W. Furthermore, the exposure apparatus includes a wafer stage82serving as a retaining unit including a θz tilt stage80on which the wafer W is placed, the θz tilt stage80moving the wafer W in a light-axis direction, and an XY stage81that moves the wafer W in X and Y directions. The position of the XY stage81is measured by a laser interferometer83. The rotation of the motor17of the shutter unit10is controlled by a controller85serving as a control unit via a motor driver84. The controller85controls the aperture time of the shutter unit10such that the wafer W is exposed to a predetermined amount of light on the basis of the output from a photodetector86that detects the part of the exposure light beam100extracted using the half mirror75.

On the other hand, the pattern area of the reticle R is exposed to a predetermined amount of light. The pattern is reduced in size to a predetermined magnification (for example, ¼ or ⅕) by the projection optical system79, and transferred onto the wafer W retained by the wafer stage82. This exposure operation is repeated on a plurality of transfer areas (shot areas) on the wafer W. Since the scan-exposure operation is repeated on the plurality of transfer areas, the application of at least one of the structures shown in the first to third exemplary embodiments to the structure for retaining the shutter blades11to13can increase the opening and closing speed of the shutter unit10. When the structure including the shutter unit10according to any one of the first to third exemplary embodiments is applied to the exposure apparatus, the exposure apparatus can maintain stabilized exposure accuracy, and can reduce the cycle time so as to improve the throughput of the exposure apparatus.

The exposure apparatus according to this exemplary embodiment can be applied to, for example, those of the step-and-scan type or of the stepper type. In an exposure apparatus of the stepper type, a wafer is moved to the next exposure position in a stepped manner by a wafer stage each time one-shot exposure is conducted. In the exposure apparatus according to this exemplary embodiment, g line having a wavelength of 436 nm, i line having a wavelength of 365 nm, or the like can be used as a light source. However, the present invention is not limited to these, and KrF excimer lasers, ArF excimer lasers, F2excimer lasers, or the like can also be used. Moreover, the projection optical system79is not limited to the dioptric optical system, and can be a catadioptric optical system in which reflective elements are partly used.

Method of Manufacturing Device

Next, a method of manufacturing a device using the above-described exposure apparatus according to the fourth exemplary embodiment of the present invention will be described with reference toFIGS. 5 and 6.FIG. 5is a flow chart of manufacturing devices, for example, semiconductor chips such as ICs and LSI circuits, LCDs, or CCD sensors. Herein, a method of manufacturing semiconductor devices will be described as an example. In Step S1(circuit design), circuits of semiconductor devices are designed. In Step S2(mask production), masks (also referred to as originals or reticles) are produced on the basis of the designed circuit patterns. In Step S2, reticles can be produced. In Step S3(wafer production), wafers (also referred to as substrates) are produced using materials such as silicon.

Step S4(wafer processing) is referred to as a front-end process in which real circuits are formed on the wafers by the above-described exposure apparatus with lithography technology using the masks or the reticles and the wafers. Step S5(assembly) is referred to as a back-end process in which semiconductor devices are produced using the wafers processed in Step S4. Step S5includes an assembly step (dicing and bonding), a packaging step (molding), and the like. In Step S6(inspection), operations, durability, and the like of the semiconductor devices produced in Step S5are checked. The semiconductor devices produced through these steps are then shipped (Step S7).

FIG. 6is a flow chart illustrating the wafer processing in Step S4in detail. In Step S11(oxidation), the surfaces of the wafers are oxidized. In Step S12(chemical vapor deposition; CVD), insulating films are deposited on the surfaces of the wafers. In Step S13(electrode formation), electrodes are formed on the wafers. In Step S14(ion implantation), ions are implanted in the wafers. In Step S15(resist processing), photosensitizer is applied to the wafers. In Step S16(exposure), the wafers are exposed to light passing through the masks or the reticles having the circuit patterns using the above-described exposure apparatus. In Step S17(development), the exposed wafers are developed.

In Step S18(etching), portions other than those of the developed resist images are removed. In Step S19(resist removing), the resist that is no longer required after etching is removed. Repetition of these steps can form multiplex circuit patterns on the wafers. In the method of manufacturing a device according to the exemplary embodiment, exposure can be stably conducted at high speed due to the use of the above-described exposure apparatus. Thus, more reliable devices can be manufactured more stably at higher speed.

According to the above-described exemplary embodiments, for example, the deformation of the shutter blades can be reduced.

This application claims the priority of Japanese Application No. 2006-326373 entitled “shutter blade apparatus, shutter unit, image pickup apparatus, exposure apparatus, and method of manufacturing device” filed Dec. 1, 2006, which is hereby incorporated by reference herein in its entirety.