JP2002203767A - Aligner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aligner wherein structure is simple and a plurality of stop mechanisms can be easily used properly if necessary. SOLUTION: An illumination optical system IOP is provided with the plural stop mechanisms 28G1, 28G2 for changing an illumination shape of an energy beam which illuminates a reticle R, and a switching mechanism 32 which moves the respective stop mechanisms 28G1, 28G2 to an optical axis direction of the energy beam and performs switching arrangement of the mechanisms on a pupil surface of the illumination optical system IOP. As the plural stop mechanisms, the iris stop mechanism 28G2 which changes at least the aperture diameter in an optical path of the energy beam almost continuously, and the aperture stop mechanism 28G1 which arranges an aperture stop plate 128 having a prescribed aperture shape in the optical path so as to enable reciprocating movement, are arranged at a prescribed interval in the optical axis direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus used in a lithography process for manufacturing, for example, a semiconductor device, a liquid crystal display device, and the like.

[0002]

2. Description of the Related Art In recent years, in a lithography process for manufacturing a semiconductor device or the like, a rectangular or arc-shaped illumination region on a mask or a reticle (hereinafter, collectively referred to as a “reticle”) on which a pattern is formed is illuminated with illumination light. A so-called slit scan method in which a reticle and a substrate such as a wafer are synchronously moved in a one-dimensional direction and the pattern is sequentially transferred onto the substrate.
A scanning exposure apparatus such as a step-and-scan method is used.

In this type of exposure apparatus, a diaphragm mechanism for changing the illumination shape of the illumination light is provided in an illumination optical system for illuminating the reticle with illumination light from a light source so as to be positioned on the surface of the reticle. The aperture mechanism has an iris aperture mechanism in which the aperture diameter in the optical path of the illumination light is changed almost continuously by the operation of a plurality of blades arranged in a shutter shape, and has a predetermined aperture shape in the optical path. There is known an aperture stop mechanism in which an aperture stop plate is arranged so as to be able to advance and retreat.

In the iris diaphragm mechanism, the aperture diameter in the optical path of the illumination light can be changed almost continuously within a predetermined range, but the changeable aperture diameter is limited. On the other hand, in the aperture stop mechanism, an aperture of a predetermined shape is formed in the aperture stop plate, and an aperture of an arbitrary shape is arranged on the optical path, so that the illumination light can be used for annular illumination, minimal illumination, quadrupole illumination, and the like. Although it can be deformed, the diameter of the opening cannot be changed almost continuously.

For this purpose, for example, a plurality of openings having different opening diameters are formed in one rotating disk, a plurality of blades are arranged in one of them in a shutter shape, and the other openings are formed in a ring shape. It is also conceivable to form it for band illumination, minimal illumination, and quadrupole illumination. With this configuration, the diameter of the opening can be changed substantially continuously and the illumination light can be variously deformed by rotating the rotating disk and disposing one of the openings in the optical path of the illumination light. Can be.

[0006]

However, in the case where a plurality of blades are arranged in a shutter shape in one opening of the rotating disk as described above, a drive such as a motor for opening and closing the blades is used. A mechanism, a transmission mechanism for transmitting the driving force of the driving mechanism to each blade, and the like need to be mounted on the rotating disk. For this reason, the structure of the diaphragm mechanism mounted on the rotating disk becomes complicated and heavy, and the rotating disk cannot be accurately rotated.

The present invention has been made by paying attention to such problems existing in the prior art. An object of the present invention is to provide an exposure apparatus which has a simple structure and can easily use a plurality of aperture mechanisms as needed.

[0008]

According to one aspect of the present invention, there is provided an illumination optical system for illuminating a mask on which a predetermined pattern is formed by an energy beam emitted from an energy beam source. In an exposure apparatus having a system, the illumination optical system moves a plurality of aperture mechanisms for changing an illumination shape of the energy beam illuminating the mask in the optical axis direction of the energy beam. And a switching mechanism for switching to a Fourier transform plane relating to the pattern of the mask or in the vicinity thereof.

According to the first aspect of the present invention, a plurality of aperture mechanisms are selectively provided on the Fourier transform plane relating to the pattern on the mask or in the vicinity thereof along the optical axis direction of the energy beam by the switching mechanism, if necessary. And can be easily used properly. Further, the plurality of aperture mechanisms are not mounted on one rotating disk or the like, but are switched independently along the optical axis direction of the energy beam in a state of being independent of each other. For this reason, the configuration of the aperture mechanisms is simple, and each aperture mechanism can be easily and more accurately switched and arranged on or near the Fourier transform plane.

According to a second aspect of the present invention, in the first aspect of the present invention, the plurality of aperture mechanisms change at least an aperture diameter in an optical path of the energy beam substantially continuously. An iris diaphragm mechanism having an aperture diaphragm plate having a predetermined aperture shape with respect to the optical path so as to be able to move in and out, and the iris diaphragm and the aperture diaphragm plate are arranged in the optical axis direction. Are arranged at predetermined intervals.

According to a third aspect of the present invention, in the second aspect of the invention, there is provided an iris diaphragm base for holding the iris diaphragm, an aperture diaphragm base for holding the aperture diaphragm plate, And a base drive mechanism for moving at least one of the iris stop base and the aperture stop base in the optical axis direction of the energy beam.

According to the second or third aspect of the present invention, the iris diaphragm and the aperture diaphragm plate can be easily switched and arranged selectively with respect to the Fourier transform plane relating to the pattern on the mask or in the vicinity thereof. Can be used properly.

According to a fourth aspect of the present invention, in the second or third aspect of the present invention, the aperture stop plate is arranged such that the iris stop is a Fourier transform surface related to the pattern of the mask or a vicinity thereof. And a flat plate which is arranged in the optical path of the energy beam when it is arranged and has an opening larger than the optical path.

According to the fourth aspect of the present invention, since the aperture stop plate is formed of a flat plate having an opening larger than the optical path, even when the iris stop is arranged in the optical path, the aperture stop plate is formed. Does not block the path of the energy beam.

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, the aperture stop plate includes a plurality of apertures having different aperture diameters and notches arranged in a circumferential direction. It is characterized by being formed by a disc to be formed.

In the invention according to claim 5 of the present application, the aperture stop plate is formed in a disk shape, and a plurality of apertures having different aperture diameters in the circumferential direction of the disk and the notch are arranged. In addition, the aperture stop plate can easily move in and out of the optical path. In addition, when the iris diaphragm is arranged in the optical path, the notch can be arranged with respect to the optical path, so that the aperture diaphragm does not block the path of the energy beam.

According to a sixth aspect of the present invention, in the first aspect of the present invention, an optical path region containing the plurality of aperture mechanisms and including an optical path through which the energy beam passes is defined as an outer region. And a housing that is airtightly partitioned, an aperture driving mechanism that is arranged outside the housing and drives the plurality of aperture mechanisms in the housing, and a driving force of the driving mechanism is transmitted through the housing to each of the aperture driving mechanisms. And a transmission unit for transmitting to the aperture mechanism.

According to the sixth aspect of the present invention, it is possible to prevent impurities such as oil generated in the aperture driving mechanism and the driving force transmission portion from entering the optical path, and to prevent the impurity from entering the optical path. The degree of cleanliness can be improved.

According to a seventh aspect of the present invention, in the invention according to the sixth aspect, the housing is provided with an illuminance uniforming mechanism for uniforming an illuminance distribution of the energy beam on the mask. A housing drive mechanism is provided, which is partially mounted and moves the housing itself along the optical axis direction of the energy beam.

According to the invention of claim 7 of the present application, the housing on which a part of the illuminance uniformizing mechanism is mounted is moved and adjusted along the optical axis direction of the energy beam, so that the illuminance distribution of the energy beam can be easily adjusted. Can be made uniform.

According to the invention described in claim 8 of the present application, in the invention described in claim 7, the entire housing is provided in the optical axis direction of the energy beam against the weight of the housing. And a biasing mechanism for biasing along.

According to the invention described in claim 8 of the present application, the housing is urged in the direction of gravity along the optical axis direction of the energy beam by the urging mechanism, and the housing is driven by the housing driving mechanism. It can be easily and stably moved along the optical axis direction without any deviation.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 schematically shows an overall configuration of an exposure apparatus 10 according to one embodiment, which includes an illumination optical device according to the present invention as an illumination optical system.

The exposure apparatus 10 synchronously moves a reticle R as a mask and a wafer W as a substrate in a one-dimensional direction (here, the Y-axis direction, which is the horizontal direction in FIG. 1). This is a step-and-scan type scanning exposure apparatus that transfers a circuit pattern formed on the reticle R to each shot area on the wafer W via the projection optical system PL, that is, a so-called scanning stepper.

The exposure apparatus 10 includes a light source 12,
An illumination optical system IOP as an illumination optical device for illuminating the reticle R with illumination light from the reticle R, a reticle stage RST as a mask stage for holding the reticle R, and illumination light (pulse ultraviolet light) emitted from the reticle R are applied to the wafer W. And a wafer stage WST as a substrate stage for holding a wafer W. Further, the exposure apparatus 10 includes a part of the illumination optical system IOP,
A reticle stage RST, a projection optical system PL, a main body column 14 for holding the wafer stage WST, and the like, a vibration isolation unit for suppressing or eliminating vibration of the main body column 14, and a control system for these components are provided.

The light source 12 has a wavelength 19 here.
An ArF excimer laser light source that outputs pulsed ultraviolet light narrowed so as to avoid an oxygen absorption band between 2 and 194 nm is used, and the main body of the light source 12 is a floor in a clean room of a semiconductor manufacturing plant. It is installed on the surface FD. The light source 12 is provided with a light source control device (not shown) for controlling the oscillation center wavelength and the spectral half width of the emitted pulsed ultraviolet light, triggering the pulse oscillation, controlling the gas in the laser chamber, and the like. It has become.

As the light source 12, a KrF excimer laser light source that outputs pulsed ultraviolet light having a wavelength of 248 nm or an F2 laser light source that outputs pulsed ultraviolet light having a wavelength of 157 nm may be used. Further, the light source 12 is provided in another room (service room) having a lower degree of cleanness than the clean room,
Alternatively, it may be installed in a utility space provided under the floor of a clean room.

The light source 12 is not shown in FIG. 1 for convenience of drawing, but is actually connected to one end (incident end) of the beam matching unit BMU via a light-blocking bellows and a pipe. . The other end (emission end) of the beam matching unit BMU is connected to a later-described first partial illumination optical system IOP1 of the illumination optical system IOP via a pipe 16 having a relay optical system built therein.

As shown in FIG. 2, the illumination optical system IOP is a first partial illumination optical system IOP as a movable partial optical system.
1 and a second partial illumination optical system IO as a stationary partial optical system
P2. As will be described later, the first partial illumination optical system IOP1 is installed on a base plate BP called a frame caster, which serves as a reference for an apparatus mounted horizontally on the floor FD. The second partial illumination optical system IOP2 is, as shown in FIG.
Are supported from below by a second support column 52 constituting

Here, the illumination optical system I will be described with reference to FIG.
Each component of the OP will be described. The first partial illumination optical system IOP1 is provided with a variable dimmer (not a variable dimmer) in which a plurality of ND filters having different dimming rates are arranged on a rotatable disk in order to adjust the average energy of each pulse of the pulsed ultraviolet light. (Shown). The pulsed ultraviolet light adjusted to a predetermined peak intensity by the variable attenuator is guided to a beam shaping optical system (not shown), and the cross-sectional shape of the pulse ultraviolet light is adjusted to the whole of the incident end of the first fly-eye lens system (not shown) Shaped to be similar to the shape. Next, a first fly-eye lens system and a second fly-eye lens system 28Fa as optical integrators are provided, and a surface light source (a number of point light sources) is formed at the exit end of each fly-eye lens system. In addition, a vibration mirror for smoothing interference fringes and weak speckles generated on the irradiated surface is provided between the two fly-eye lenses. Further, after the second fly-eye lens system 28Fa, an aperture mechanism 28G and an auxiliary field lens system 28F
Fb, beam splitter 28H, first relay lens system 2
8I, and a movable reticle blind 28J as a movable field stop constituting a reticle blind mechanism.

The second partial illumination optical system IOP2
Is a second illumination system housing 26B as a second illumination system housing, and a fixed reticle blind 28 stored in a predetermined positional relationship in the second illumination system housing 26B.
K, lens 28L, mirror M3, second relay lens system 2
8M, a lens 28N, a mirror M4, a main condenser lens 28O, and the like.

As shown in FIG. 2, an aperture mechanism 2 is located near the exit surface of the second fly-eye lens system 28Fa.
8G is arranged. The aperture mechanism 28G has an aperture diaphragm plate having a predetermined aperture shape in the optical path of the pulsed ultraviolet light so as to be able to move in and out, as will be described later.
G1 and an iris diaphragm mechanism 28G2 for changing the aperture diameter in the optical path of the pulsed ultraviolet light almost continuously. The aperture stop mechanism 28G1 and the iris stop mechanism 28G2 are arranged at predetermined intervals along the optical axis direction of the pulsed ultraviolet light.

The aperture stop mechanism 28G1 and the iris stop mechanism 28G2 are moved along the optical axis direction of the pulsed ultraviolet light by a stop switching motor 32 controlled by an illumination control device (not shown), and The Fourier transform plane for the R pattern, that is, the pupil plane of the illumination optical system IOP is selectively switched and arranged. That is, in the present embodiment, one of the aperture stop mechanism 28G1 and the iris stop mechanism 28G2 is selectively switched with respect to the pupil plane (stop position) of the illumination optical system IOP by the stop switching motor 32. Is configured.

A beam splitter 28H having a large transmittance and a small reflectance is disposed on the optical path of the pulsed ultraviolet light behind the stop mechanism 28G. Further, on the optical path behind the first and second relay lens systems 28I, a movable reticle. Blinds 28
J (not shown in FIG. 2; see FIG. 1) are sequentially arranged.

The movable reticle blind 28J has, for example, two L-shaped movable blades as movable portions and an actuator for driving the movable blades. The positions of the two movable blades in the direction corresponding to the scanning direction of the reticle R and the direction corresponding to the non-scanning direction orthogonal to the scanning direction are variable. The movable reticle blind 28J further limits the illumination area on the reticle R defined by the fixed reticle blind 28K by the movable blade at the start and end of the scanning exposure, as described later, in order to prevent unnecessary portions from being exposed. Used for

Further, the light source 1 of the beam splitter 28H
On the reflected light path from the second side, an integrator sensor 34 composed of a photoelectric conversion element is arranged.
On the reflected light path from the reticle R side of 8H, a reflected light monitor 38 composed of a photoelectric conversion element similar to the integrator sensor 34 is arranged. This beam splitter 28
H has the property of transmitting most of the exposure light (about 97%) and reflecting the rest.

The fixed reticle blind 28K is arranged on a surface slightly defocused from a conjugate plane with respect to the pattern surface of the reticle R near the incident end of the second illumination system housing 26B, and defines an illumination area on the reticle R. An opening having a shape is formed. At least one of each relay lens system 28M, lens 28L, and mirror M4 housed in the second illumination system housing 26B has its optical axis movable with respect to the optical axis of another lens or mirror during the non-exposure operation. Is configured.

In the above configuration, the entrance surface of the first fly-eye lens system, the entrance surface of the second fly-eye lens system 28Fa, the blade arrangement surface of the movable reticle blind 28J, and the pattern surface of the reticle R are optically mutually A light source surface formed on the exit surface side of the first fly-eye lens system 28C, a light source surface formed on the exit surface side of the second fly-eye lens system 28Fa, and a Fourier transform surface of the projection optical system PL are set to be conjugate. The exit pupil plane) is optically set to be conjugate to each other, forming a Koehler illumination system.

With the illumination optical system IOP thus configured, a predetermined illumination area on the reticle R held on the reticle stage RST (a slit-shaped or rectangular illumination area extending linearly in the X-axis direction). Is illuminated with a uniform illuminance distribution. Here, the rectangular slit-shaped illumination light applied to the reticle R is set to be elongated in the X-axis direction (non-scanning direction) at the center of the circular projection field of the projection optical system PL in FIG. The width of the light in the Y-axis direction (scanning direction) is set substantially constant.

The pulsed ultraviolet light reflected by the beam splitter 28H enters the integrator sensor 34, and outputs the output of the integrator sensor 34 and the wafer W
A correlation coefficient with the illuminance (exposure amount) of the pulsed ultraviolet light on the surface of is obtained.

The reflected light from the pattern surface of the reticle R is reflected by the main condenser lens 28O, mirror M4, lens 28N, second relay lens system 28M, mirror M3,
After passing through the lens 28L, the opening of the fixed reticle blind 28K, the opening of the blade of the movable reticle blind 28J, and the first relay lens system 28I, the light is reflected by the beam splitter 28H, enters the reflected light monitor 38, and receives the reflected light. Based on the output of the monitor 38, the measurement of the transmittance of the reticle R is obtained.

The housing for holding each optical member constituting the illumination optical system IOP, the joint structure between these housings, and the like will be described in further detail later. Returning to FIG. 1, the main body column 14 includes a plurality of (here, four) support members 40A to 40D provided on the base plate BP (however, the support columns 40C and 40D on the back side of the paper are not shown). And vibration isolating units 42A to 42D fixed to the upper portions of these supporting members 40A to 40D, respectively (however, the vibration isolating units 42C and 42D on the back side of the paper in FIG. 1 are not shown) and are supported substantially horizontally. Lens barrel surface plate 44 and lens barrel surface plate 44
And first and second support columns 48 and 52 provided thereon.

The anti-vibration units 42A to 42D are connected in series (or in parallel) above the support members 40A to 40D, respectively.
And a voice coil motor which is provided with an adjustable internal pressure. By these vibration isolating units 42A to 42D, micro vibrations transmitted from the floor surface FD to the lens barrel base 44 via the base plate BP and the support members 40A to 40D are insulated at the micro G level. .

A circular opening in a plan view is formed at the center of the lens barrel base 44, and a projection optical system PL is inserted therein from above with the optical axis direction being the Z axis direction. A flange FLG integrated with the lens barrel is provided on the outer periphery of the lens barrel of the projection optical system PL. The flange FLG forms a so-called kinematic support mount that supports the projection optical system PL at three points with respect to the lens barrel base 44 via points, surfaces, and V-grooves.

The wafer base plate 54 is mounted on a base plate BP. Also, the first support column 48
Four legs 58 (the legs on the back side of the drawing are not shown) planted on the upper surface of the lens barrel base 44 so as to surround the projection optical system PL, and a reticle supported substantially horizontally by the four legs 58 A base platen 60 is provided. Similarly, the second support column 52 includes four columns 62 (the columns on the back side of the drawing are not shown) planted on the upper surface of the lens barrel base 44 so as to surround the first column 48. , And a top plate 64 supported substantially horizontally by these four columns 62. The above-described second partial illumination optical system IOP2 is supported by the top plate 64 of the second support column 52.

When the reticle stage RST and the wafer stage WST are moved, vibrations in the six-degree-of-freedom direction of the main body column 14 obtained based on the measured values of the vibration sensors provided on the main body column 14 are removed. In addition, the speed control of the vibration isolating units 42A to 42D is performed by, for example, feedback control or feedback control and feedforward control, so that the vibration of the main body column 14 is effectively suppressed.

The reticle stage RST is arranged on a reticle base surface plate 60 constituting the first support column 48 constituting the main body column 14 via a vibration isolating unit (not shown). The reticle stage RST is driven by a reticle stage drive system composed of, for example, a magnetic levitation type two-dimensional linear actuator, and linearly drives the reticle R on the reticle base surface plate 60 with a large stroke in the Y-axis direction, and in the X-axis direction. And a small drive in the θz direction (rotational direction around the Z axis).

A part of the reticle stage RST includes
A movable mirror 72 that reflects a length measurement beam from a reticle laser interferometer 70, which is a position detection device for measuring the position and the movement amount, is attached. The reticle laser interferometer 70 is fixed to the reticle base surface plate 60, and the position (θz) of the reticle stage RST in the XY plane with respect to the fixed mirror Mr fixed to the upper end side surface of the projection optical system PL.
(Including rotation), for example, with a resolution of about 0.5 to 1 nm.

Reticle stage RST (that is, reticle R) measured by reticle laser interferometer 70
Based on the position information (or speed information), the reticle stage drive system is controlled so that the position information (or speed information) matches the command value (target position, target speed).

As the projection optical system PL, here,
A 1/4, 1/5, or 1/6 reduction magnification refractive optical system consisting of only a refractive optical element (lens element) using quartz or fluorite as an optical glass material, or a refractive optical element (lens) and a reflective optical element ( A catadioptric optical system (catadioptric optical system) in combination with a mirror or a reflective optical system consisting of only a reflective optical element is used.

On the other hand, the wafer stage WST is disposed on a wafer base plate 54, and is, for example, a magnetic levitation type.
It can be freely driven in the XY plane by a wafer stage drive system including a two-dimensional linear actuator and the like. The wafer W is fixed on the upper surface of the wafer stage WST via a wafer holder 76 by vacuum suction or the like.

XY position and rotation amount of wafer stage WST (yaw amount, rolling amount, pitching amount)
Is a reference mirror Mw fixed at the lower end of the lens barrel of the projection optical system PL.
Is measured in real time at a predetermined resolution, for example, a resolution of about 0.5 to 1 nm by a wafer laser interferometer 80 that measures a change in the position of a movable mirror 78 fixed to a part of the wafer stage WST with reference to.

Next, the housing for holding the optical members of the first and second partial illumination optical systems IOP1 and IOP2 constituting the illumination optical system IOP and the joint structure thereof will be described in detail with reference to FIG. .

FIG. 2 is a sectional view showing the entire second partial illumination optical system IOP2 and a part of the first partial illumination optical system IOP1. As is apparent from FIG. 2, the illumination optical system IOP includes at least one optical member (an optical element such as a lens or a mirror, or an aperture or a blade of a reticle blind) and a housing that holds the optical member. A plurality of optical units as a group of optical elements are provided.

More specifically, the first partial illumination optical system IOP1 comprises an optical unit 84A having two L-shaped movable blades BL as movable parts, a housing 82A holding the blades, and a first relay. An optical unit 84B having a lens system 28I and a housing 82B holding the same, an optical unit 84C having a beam splitter 28H and a housing 82C holding the same, a second fly-eye lens system 28
The optical unit 84D includes a Fa, an auxiliary field lens system 28Fb, an aperture stop mechanism 28G1, an iris stop mechanism 28G2, and a housing 82D that holds them, and a number of other optical units are sequentially joined. I have.

The housings 82A, 82B, 82C,
The inner surface of 82D is subjected to a chemical clean treatment, for example, by coating a fluorine-based resin or forming a metal film (a ceramic film, a stainless steel film, or the like) by plasma spraying. Alternatively, these housings 82A
As a material of the ~ 82D itself, a chemically clean material such as stainless steel or Teflon (registered trademark) may be used. In addition, for all the cases described below,
It is formed in the same manner as above.

The housing 8 constituting the optical unit 84A
2A, the movable blade BL having a large movable amount is held as an optical member.
It is configured to be driven by an actuator 86 arranged outside the housing 82A. In this case, the movable reticle blind 28J described above is constituted by the two movable blades BL and the actuator 86.

Here, as the actuator 86, for example, a linear motor having a mover supported by an air bearing in a non-contact manner with a guide surface is used. When such an actuator is used, both the degree of cleanliness and the degree of chemical cleanliness can be improved as compared with the case where the movable blade is driven by a rotary motor via a ball screw mechanism. That is, non-contact drive reduces dust generation compared to contact driven linear guides, and eliminates the need for ball screws and motor bearings, eliminating degassing from these and improving chemical cleanliness. Can be.

Further, a sensor 90 for detecting a driving amount of the movable blade BL by the actuator 86 is provided outside the housing 82A. Sensor 9 during scanning exposure
By controlling the actuator 86 based on the output of 0, the movable blade BL is moved synchronously with the reticle R, thereby preventing unnecessary portions from being exposed.

The first relay lens system 28I includes a housing 8
It has an actuator 92 attached to the outside of 2B, a first lens 94 that can be finely driven in the XY shift and tilt directions by a moving mechanism (not shown), and a non-movable second lens 96. In this case, there is a possibility that the optical arrangement of the first relay lens system 28I is shifted from an expected position by vibration transmitted to the housing 82B via the housing 82A by driving the movable blade BL.
2, the position shift can be adjusted by slightly driving the first lens 94 in the XY shift and tilt directions.

Further, a sensor 98 for detecting a driving amount of the first lens 94 by the actuator 92 is provided outside the housing 82B. The above-described correction is performed by controlling the actuator 92 based on the output of the sensor 98.

The housing 8 constituting the optical unit 84C
In 2C, a beam splitter 28H is provided obliquely at approximately 45 ° with respect to the optical path of the pulsed ultraviolet light. Further, the integrator sensor 34 and the reflected light monitor 38 are mounted on the housing 82C from outside via the mounting members 100 and 102, and the wiring of these optical sensors is disposed outside the housing 82C, and the wiring is Care is taken not to lower the degree of chemical cleanliness in the housing 82C. That is, the integrator sensor 34 and the reflected light monitor 38 are in a state where only their light receiving surfaces face the inside of the housing 82C.

The housing 8 constituting the optical unit 84D
The 2D houses a second fly-eye lens system 28Fa and an auxiliary field lens system 28Fb. In the housing 82D, an aperture stop mechanism 28G1 and an iris stop mechanism 28G2 are accommodated and arranged at predetermined intervals in the optical axis direction of the pulsed ultraviolet light. The aperture stop mechanism 28 is provided by an aperture switching motor 32 provided outside the optical path area including the optical path in the housing 82D.
G1 or the iris diaphragm mechanism 28G2 is connected to the illumination optical system IOP.
Are selectively switched and arranged at the aperture position serving as the pupil plane. The details of the aperture stop mechanism 28G1 and the iris stop mechanism 28G2 will be described later.

A stretchable bellows-like member 104A as a connection portion between the housing 82A of the optical unit 84A and the housing 82B of the optical unit 84B as a connection part capable of making the inside airtight against outside air. Are connected detachably in a state where transmission of vibration between the two is restricted.
As in the case between the housings 82A and 82B, the optical unit 84
B between the housing 82B of the optical unit 84C and the housing 82C of the optical unit 84C, and between the housing 82C of the optical unit 84C and the housing 82D of the optical unit 84D via the bellows-like members 104B and 104C which can be extended and contracted. It is detachably connected.

The bellows-like members 104A, 104B,
As the 104C, for example, a fluororubber that has been subjected to secondary vulcanization at a temperature of about 240 ° C. for about 24 hours is used. The bellows-like members 104A, 104
As B and 104C, those obtained by coating at least the inner surface with a chemical clean treatment, for example, a fluorine-based resin may be used. Further, a metal such as stainless steel may be used as the material of the bellows-like member.

The housings 82A to 82D of the optical units 84A to 84D in the first partial illumination optical system IOP1 configured as described above, particularly the bellows-like members 104A to 104C.
The housings 82A to 82D connected by the bellows-like member 104
If only the supports A to 104C are used, the positions of the housings 82A to 82D are not stable, so that it is necessary to hold the housings 82A to 82D from outside.

Therefore, as shown in FIG.
The flanges 106A, 106B, 1
06C and 106D are not provided. These flanges 106A to 106D are integrated with the housings 82A to 82D, and the housings 82A to 82D and the flanges 106A to 1D are integrated.
As the material of 06D, a material having low thermal expansion, for example, Invar is used. Each of these housings 82A to 82D has a plurality of pairs of support shelves 110A, 110B, 110C, 1 on the inner surface.
10D is housed in a box-shaped illumination system housing member 108 formed. That is, the optical units 84A to 84A
D, flanges 106A-1 of housings 82A-82D
06D is placed on these support shelves 110A to 110D, and is positioned and fixed at a predetermined position by a fixing screw (not shown) or the like.

The housings 82A to 106D are provided at contact portions between the flanges 106A to 106D of the housings 82A to 82D and the supporting shelves 110A to 110D of the illumination system housing member 108.
In order to hold 82D with high accuracy, it is desirable to spray metal materials such as ceramics and stainless steel.

The bellows-like members 104A-104
Housing 82 of optical units 84A to 84D connected by C
A to 82D, the first partial illumination optical system IOP1
An illumination system housing 26A (see FIG. 3) is formed, in which a pulsed ultraviolet light as an energy beam is passed, and an optical path chamber 112 as an optical path area for accommodating the optical members of the optical units 84A to 84D. Are formed. Further, inside the illumination system housing member 108, the optical units 84 </ b> A to 84 </ b> A
A housing chamber 114 is formed as an outer region for housing a driving mechanism such as an actuator or a motor in 84D.

A gas such as a low-absorbent gas (for example, clean dry nitrogen gas or helium gas having a concentration of air (oxygen) of less than 1 ppm) is supplied into the optical path chamber 112. Chemical cleanliness is being improved. Further, a gas such as dry air is supplied into the storage chamber 114, so that the cleanness of the storage chamber 114 is improved.

The remaining optical members constituting the first partial illumination optical system IOP1, that is, the vibrating mirror, the first fly-eye lens system, the beam shaping optical system, and the variable dimmer are also chemically clean as described above. The optical unit is constituted by being held in a processed housing.
Then, the housing of each optical unit is connected via the same bellows-like member as described above in a state where transmission of vibration between the two is restricted.

Next, the detailed configuration of the second partial illumination optical system IOP2 will be described. As shown in FIG. 2, the second partial illumination optical system IOP2 includes a main condenser lens 28.
O, a mirror M4, a lens 28N, and an optical unit 84E having a housing 82E for holding them, a second relay lens system 28M and an optical unit 84F having a housing 82F for holding the same, a mirror M3, a lens 28L, An optical unit 84 having a housing 82G for holding these
G and an optical unit 84H having a fixed reticle blind 28K and a housing 82H holding the fixed reticle blind 28K are sequentially joined.

The housing 82E of the optical unit 84E and the housing 82F of the optical unit 84F are connected along the arrangement direction while maintaining airtightness by a duct-like connecting member 116A. Similarly, the housing 82F of the optical unit 84F and the housing 82G of the optical unit 84G are connected along the arrangement direction while maintaining airtightness by the connecting member 116B. Also, the optical unit 84
The housing 82G of G and the housing 82H of the optical unit 84H are joined and fixed via an O-ring 118 formed of a chemically clean material.

As described above, the casings 82E to 82H are sequentially joined to form the second illumination system housing 26B of the second partial illumination optical system IOP2. Also,
Covers 120A and 120B for blocking external air from contacting the main condenser lens 28O and the lens 28L are respectively provided on the housings 82E and 82G located at both ends (emission end and entrance end) of the second illumination system housing 26B. Installed.

The first partial illumination optical system IOP1
As in the case of the first illumination system housing 26A, the light path chamber in the second illumination system housing 26B of the second partial illumination optical system IOP2 also has a low absorptive gas (for example, the concentration of air (oxygen) is less than 1 ppm). (Eg, clean dry nitrogen gas or helium gas) is supplied to improve the degree of chemical cleanliness in the optical path chamber.

Note that the low absorption gas (for example, when the concentration of air (oxygen) is 1%) is also provided in the lens barrel of the projection optical system PL described above.
Gases such as clean dry nitrogen gas or helium gas (less than ppm) are purged.

Further, the second partial illumination optical system IOP2
Between the housing 82H of the optical unit 84H and the housing 82A of the optical unit 84A in the first partial illumination optical system IOP1 as a connecting portion capable of making the inside airtight against outside air. Free bellows-like member 1
They are connected via 04D in a state where transmission of vibration between them is restricted.

Next, the structure of the aperture mechanism 28G in the first partial illumination optical system IOP1 will be described in detail with reference to FIGS. As shown in FIG. 3, the housing 82D is supported in the illumination system housing member 108 via a plurality of guides 122 so as to be movable along the optical axis direction of the pulsed ultraviolet light. In the housing 82D, an aperture stop base 124 of the aperture stop mechanism 28G1 and an iris stop base 126 of the iris stop mechanism 28G2 are arranged at predetermined intervals. The aperture stop base 124 and the iris stop base 126 are integrally connected to each other by a connecting member 127. For example, the connecting members 1 disposed at the four corners of the bases 124 and 126, respectively.
27. The aperture stop base 124 and the iris stop base 126 can be moved in the optical axis direction of the pulsed ultraviolet light by the stop switching motor 32.
It is housed in the illumination system housing member 108. The base 12
No. 4,126, movement in the direction intersecting the optical axis is restricted, and movement in the optical axis direction is allowed. Therefore, openings 124a and 126a larger than the optical path are formed in the bases 124 and 126 for transmitting the pulsed ultraviolet light.

The aperture switching motor 32 is mounted on the outer surface of the housing 82D, and its drive shaft 32a projects into the housing 82D and is in contact with the aperture stop base 124. When the drive shaft 32a of the aperture switching motor 32 is driven in the vertical direction under the control of the illumination control device 30, the aperture stop base 124 and the iris stop base 126 are integrated with the light of pulsed ultraviolet light. The aperture stop mechanism 28G1 or the iris stop mechanism 28G2 is moved in the axial direction and the illumination optical system I
The aperture position is selectively switched to the aperture position on the pupil plane of the OP. That is, a base drive mechanism for moving the aperture stop base 124 and the iris stop base 126 by the stop switching motor 32 is configured. FIG. 3 shows a state where the iris diaphragm mechanism 28G2 is arranged at the diaphragm position on the pupil plane of the illumination optical system IOP.

The aperture switching motor 32 is provided on the support shelf 11.
It is arranged in the opening 110Da formed in 0D. The size of the opening 110Da is formed to be larger than the diameter of the aperture switching motor 32, and when the housing 82D moves in the optical axis direction by driving the housing moving motor 158 described later. Support shelf 110D and aperture switching motor 3
2 can be avoided.

As shown in FIG. 3, the aperture stop base 12
On the rotary shaft 13, a substantially disk-shaped aperture stop plate 128 is provided.
It is rotatably supported via a bearing 0 and a bearing 132. As shown in FIG. 4, a cutout 134 is formed in a part of the peripheral side of the aperture stop plate 128 as an opening larger than the optical path of the pulsed ultraviolet light. That is, the aperture stop plate 128 has a partially notched disk shape due to the formation of the notch portion 134. Note that an opening having a size that does not block the optical path of the pulsed ultraviolet light may be formed instead of the cutout 134. A plurality of (here, five) aperture stops 136A, 1 having different aperture shapes are provided on the aperture stop plate 128.
36B, 136C, 136D, and 136E are arranged at substantially equal intervals in the circumferential direction. These aperture stops 136A
136E, for example, an aperture stop made of a small circular aperture for reducing the σ value which is a coherence factor, a ring-shaped aperture stop for annular illumination, and, for example, four apertures eccentrically arranged for a modified light source method And a modified illumination aperture stop.

As shown in FIG. 3, an aperture stop motor 138 as an aperture drive mechanism is mounted on the outer surface of the housing 82D, and its motor shaft is directly connected to the rotating shaft 130 of the aperture stop plate 128. When the aperture stop motor 138 is rotated under the control of the illumination control device 30, the aperture stop plate 128 is rotated to an arbitrary circumferential position, and any one of the aperture stops 136A to 136E or the notch is formed. 134 is arranged on the optical path of the pulsed ultraviolet light, that is, on the exit surface of the second fly-eye lens system 28Fa. When the iris diaphragm mechanism 28G2 is arranged at the diaphragm position on the pupil plane of the illumination optical system IOP,
The notch 134 is arranged on the optical path of the pulsed ultraviolet light.

As shown in FIG. 4, the aperture stop base 12
A diaphragm plate support member 140 composed of a plurality of (here, six) roller bearings or the like is rotatably disposed on the reference numeral 4 via a mounting member 141 at an arbitrary interval in the circumferential direction. . When the aperture stop plate 128 is rotated, these aperture plate support members 140 are connected to the aperture stop plate 12.
The roller 8 is rotatably contacted with the lower surface of the aperture 8 to support and rotate the aperture stop plate 128. Further, even when the notch 134 is arranged at an arbitrary (any) circumferential position along with the rotation of the aperture stop plate 128, the aperture stop plate 128 is supported by at least three aperture plate support members 140. It has become.

Next, the iris diaphragm mechanism 28G2 is shown in FIGS.
This will be described with reference to FIG. As shown in FIGS. 3 and 5, a plurality of blades 142 are provided at the periphery of the opening 126 a of the iris diaphragm base 126 in the iris diaphragm mechanism 28 G2 so as to be able to open and close. One end of a pin 142a is fixed to each of the plurality of blades 142. The other end of the pin 142a is fixed to an annular rotary pulley 144. A pair of upper and lower annular grooves 144a and 144b are formed on the outer periphery of the annular rotary pulley 144. Further, the size of the hole of the rotary pulley 144 is large enough not to block the optical path of the pulsed ultraviolet light.

A drive pulley 146 is rotatably supported on the upper surface of the end of the iris diaphragm base 126 via a bearing 148, and a pair of upper and lower annular grooves 146a, 146 are provided on the outer periphery thereof.
b is formed. Drive pulley 146 and rotary pulley 1
44, the upper annular grooves 146a, 144a
Connection wires 150A, 150B are stretched between the lower and upper annular grooves 146b, 144b, respectively. An iris diaphragm motor 152 as a diaphragm drive mechanism is mounted on the outer surface of the housing 82D, and its motor shaft is
46.

When the iris diaphragm motor 152 is rotated under the control of the illumination control device 30, the blade 142 is opened and closed via the driving pulley 146, the connecting wires 150A and 150B, and the rotating pulley 144, and the pulse The aperture diameter on the optical path of the ultraviolet light is continuously changed. That is, the driving pulley 146, the connecting wires 150A, 150B
And the rotating pulley 144, the iris diaphragm motor 152
Is transmitted to the blade 142 as a throttle unit.

As shown in FIG. 3, the aperture stop mechanism 28
The space between the rotating shaft 130 of the aperture stop plate 128 and the bearing 132 at G1 is kept airtight by O-rings 154A, 154B and a bellows-like member 156A. The space between the drive pulley 146 and the bearing 148 of the iris diaphragm mechanism 28G2 is also kept airtight by an O-ring 154C and a bellows-like member 156B. These bellows-like members 156A, 156B are adapted to be deformed when the aperture stop base 124 and the iris stop base 126 move in the optical axis direction by the stop switching motor 32. . In addition, these bellows-like members 1
56A and 156B are the bellows-like members 104A to 104A.
Like C, it has been subjected to chemical clean processing and has an expansion ratio that does not hinder the movement of each of the bases 124, 126 and the housing 82D. Thereby, the housing 82D
The reduction in the degree of chemical cleanliness inside is suppressed.

Next, the second fly-eye lens system 2 constituting a part of the illumination uniforming mechanism housed in the housing 82D
A configuration for moving and adjusting 8Fa along the optical axis direction of pulsed ultraviolet light will be described. As shown in FIG. 3, a housing moving motor 158 as a housing drive mechanism is provided in the illumination system housing member 108, and its drive shaft 158a penetrates the support shelf 110D and abuts on the housing 82D. Have been.
Then, the drive shaft 158a of the housing moving motor 158
Is driven in the vertical direction under the control of the illumination control device 30, the casing 82D is moved in the optical axis direction of the pulsed ultraviolet light, and the position of the second fly-eye lens system 28Fa is adjusted. Thereby, the illuminance distribution of the pulsed ultraviolet light illuminated on the reticle R is made uniform, and for example, the spread of the pulsed ultraviolet light is corrected.

An air cylinder 160 as an urging mechanism is arranged in the illumination system accommodating member 108 so as to be located on the opposite side of the casing moving motor 158 across the optical path of the pulsed ultraviolet light in the casing 82D. Installed and its piston rod 160
a is in contact with the housing 82D through the support shelf 110D. When the casing 82D is moved in the optical axis direction of the pulsed ultraviolet light by the casing moving motor 158, the piston rod 160a of the air cylinder 160 is controlled by the illumination control device 30 via the cylinder driving mechanism 162. And the entire housing 82D is lifted against its weight.

Next, the exposure operation of the exposure apparatus 10 configured as described above will be described. As a premise, various exposure conditions for scanning and exposing a shot area on the wafer W with an appropriate exposure amount (target exposure amount) are set in advance. Preparation work such as reticle alignment and baseline measurement using a reticle microscope (not shown) and an off-axis alignment sensor (not shown) is performed, and then fine alignment (EGA (Enhanced (Alignment) and the like are completed, and the arrangement coordinates of a plurality of shot areas on the wafer W are obtained.

Further, the illumination control device 30 selects which of the aperture stop mechanism 28G1 and the iris stop mechanism 28G2 is used in the illumination optical system IOP. Based on this selection result, the aperture switching motor 32
The aperture stop mechanism 28G1 and the iris stop mechanism 28G
2 is moved in the optical axis direction of the pulsed ultraviolet light, and one of the aperture mechanisms 28G1 and 28G2 is switched to the aperture position on the pupil plane of the illumination optical system IOP.

That is, when the iris diaphragm mechanism 28G2 is selected, the drive shaft 32a of the diaphragm switching motor 32 is moved toward the diaphragm switching motor 32 (the protrusion of the drive shaft 32a is reduced). Thereby, the aperture mechanism 28
The entire G is arranged at its lowest position in the optical axis direction of the pulsed ultraviolet light along a guide (not shown) due to its own weight. Here, the iris diaphragm base 126 of the iris diaphragm mechanism 28G2 and the aperture diaphragm base 124 of the aperture diaphragm mechanism 28G1 are integrally arranged at a predetermined interval via a plurality of connecting members 127. For this reason, the iris diaphragm base 1
Reference numeral 26 is also arranged at the lowest position in the optical axis direction of the pulsed ultraviolet light, and as shown in FIG. 3, the blade 142 of the iris diaphragm mechanism 28G2 is arranged at the diaphragm position on the pupil plane of the illumination optical system IOP.

In this state, the aperture plate 128 of the aperture stop mechanism 28G1 is driven by the aperture stop motor 138, so that the notch 134 is formed so that the aperture plate 128 does not block the pulsed ultraviolet light. Are rotated in the optical path. The blade 1 of the iris diaphragm mechanism 28G2
42 is opened and closed by driving the iris diaphragm motor 152 so that a desired opening diameter is secured.

On the other hand, when the aperture stop mechanism 28G1 is selected, the drive shaft 32a of the aperture switching motor 32 is moved to the stop mechanism 28G, and the drive shaft 32a pushes up the aperture stop base 124. Thus, the entire diaphragm mechanism 28G is pushed up along a guide (not shown), and is arranged at the uppermost position in the optical axis direction of the pulsed ultraviolet light. Along with the movement of the entire aperture mechanism 28G, the aperture stop base 12
Reference numeral 4 is also disposed at the uppermost position in the optical axis direction of the pulsed ultraviolet light, and the aperture stop plate 128 of the aperture stop mechanism 28G1 is disposed at the stop position on the pupil plane of the illumination optical system IOP.

In this state, the blades 142 of the iris diaphragm mechanism 28G2 are arranged so as to secure the maximum aperture diameter so as not to block the pulsed ultraviolet light by driving the iris diaphragm motor 152. Then, the aperture stop plate 128 is rotated by driving the aperture stop motor 138, and the aperture stops 136A to 136E having a desired aperture shape are arranged in the optical path of the pulsed ultraviolet light.

When the preparatory operation for exposure of the wafer W is completed in this way, the scanning value for the exposure of the first shot of the wafer W is monitored while monitoring the measurement value of the wafer laser interferometer 80 based on the alignment result. Move wafer stage WST to the start position.

Then, scanning of reticle stage RST and wafer stage WST in the Y direction is started, and when both stages RST and WST reach their respective target scanning speeds,
The pattern region of the reticle R starts to be illuminated by the pulsed ultraviolet light, and the scanning exposure starts.

Prior to the start of the scanning exposure, the light source 12
Has been started, but the movement of each movable blade BL of the movable reticle blind 28J constituting the reticle blind device is controlled in synchronization with the movement of the reticle stage RST. The blocking of the irradiation of the ultraviolet light is the same as in a normal scanning stepper.

In particular, at the time of the above scanning exposure, the moving speed Vr of the reticle stage RST in the Y-axis direction and the wafer stage WS
Reticle stage RST such that the moving speed Vw of T in the Y-axis direction is maintained at a speed ratio corresponding to the projection magnification (1/4, 1/5 or 1/6) of projection optical system PL.
And the wafer stage WST is controlled synchronously.

Then, different areas of the pattern area of the reticle R are sequentially illuminated with the pulsed ultraviolet light, and the illumination of the entire pattern area is completed, whereby the scanning exposure of the first shot on the wafer W is completed. Thereby, the pattern of the reticle R is reduced and transferred to the first shot via the projection optical system PL.

Next, the same scanning exposure as described above is performed on the second shot. In this manner, the scanning exposure of the shot on the wafer W and the stepping operation for the next shot exposure are repeatedly performed, and the pattern of the reticle R is sequentially transferred to all the exposure target shots on the wafer W.

Therefore, according to the present embodiment, the following effects can be obtained. (1) The exposure apparatus 10 includes an illumination optical system IOP that illuminates a reticle R on which a predetermined pattern is formed by pulsed ultraviolet light emitted from a light source 12.
The illumination optical system IOP includes an aperture stop mechanism 28G1 and an iris stop mechanism 28G2 for changing the illumination shape of the pulsed ultraviolet light applied to the reticle R, and each of the stop mechanisms 28G1 and 28G.
And a switching mechanism 32 for moving the lens 2 in the optical axis direction of the pulsed ultraviolet light to switch and arrange it on the pupil plane of the illumination optical system IOP.

For this reason, if necessary, each of the aperture mechanisms 28G
1, 28G2 can be selectively switched and arranged with respect to the pupil plane of the illumination optical system IOP along the optical axis direction of the pulsed ultraviolet light by the switching mechanism 32, and can be easily used properly. Also, the aperture stop mechanism 28G1 and the iris stop mechanism 28G2 are not mounted on a single rotating disk or the like, but are switched independently along the optical axis direction of the pulsed ultraviolet light in a state where they are formed independently of each other. It has become. For this reason, the aperture mechanism 28
The configuration of G is simple, and each aperture mechanism 28G1,
28G2 can be easily and accurately switched to a predetermined position with respect to the pupil plane of the illumination optical system IOP.

(2) In this exposure apparatus 10, the aperture mechanism 28G includes an iris aperture mechanism 28G2 that changes the aperture diameter in the optical path of pulsed ultraviolet light almost continuously, and an aperture stop having a predetermined aperture shape in the optical path. And an aperture stop mechanism 28G1 for arranging the plate 128 so as to be able to move back and forth.
The iris diaphragm mechanism 28G2 and the aperture diaphragm mechanism 28G1 are arranged at a predetermined interval. For this reason, the iris diaphragm mechanism 28G2 and the aperture diaphragm mechanism 28G1
Can be selectively switched and disposed with respect to the pupil plane of the illumination optical system IOP, and can be easily used properly.

(3) In the exposure apparatus 10, the iris stop base 126 holding the iris stop mechanism 28G2 and the aperture stop base 124 holding the aperture stop mechanism 28G1 are arranged in a state of being integrally connected. Have been. And
The iris stop base 126 and the aperture stop base 124 are moved by the base drive mechanism 32 in the optical axis direction of the pulsed ultraviolet light. Therefore, the iris diaphragm mechanism 28G2 and the aperture diaphragm mechanism 28G1 can be easily switched and arranged with respect to the pupil plane of the illumination optical system IOP by moving the base driving mechanism 32 in the optical axis direction of the pulsed ultraviolet light. it can.

(4) In the exposure apparatus 10, the aperture stop plate 128 is formed of a flat plate having a notch 134 larger than the optical path of the pulsed ultraviolet light, and the iris stop mechanism 28G2 is disposed on the pupil plane of the illumination optical system IOP. In this case, the notch 134 of the aperture stop plate 128 is arranged in the optical path of the pulsed ultraviolet light. For this reason, the iris diaphragm mechanism 2
Even when 8G2 is arranged on the pupil plane of the illumination optical system IOP, the aperture stop plate 128 does not block the path of the pulsed ultraviolet light.

(5) In the exposure apparatus 10, the aperture stop plate 128 has a plurality of apertures 136 having different aperture diameters.
A to 136E and a notch 134 are formed in a partially notched disk shape arranged in the circumferential direction. For this reason, the aperture stop plate 12
8 can easily be moved in and out of the optical path of the pulsed ultraviolet light. In addition, the blade 142 of the iris diaphragm mechanism 28G2
Is located in the optical path of the pulsed ultraviolet light, the notch 1
34 can be arranged with respect to the optical path, so that the aperture stop plate 128
Does not block the path of the pulsed illumination light.

(6) In the exposure apparatus 10, the optical path region including the optical path through which the pulsed ultraviolet light passes is sealed in the housing 82D accommodating the iris diaphragm mechanism 28G2 and the aperture diaphragm mechanism 28G1 from the outer region. It is formed by partitioning. The diaphragm driving mechanisms 152 and 138 that drive the iris diaphragm mechanism 28G2 and the aperture diaphragm mechanism 28G1 and the transmission unit that transmits the driving force of the diaphragm driving mechanisms 152 and 138 to the respective diaphragm mechanisms 28G2 and 28G1 are formed in an outer region. Are located in For this reason, the aperture driving mechanism 152, 1
Impurities such as oil and the like generated at the transmission portion 38 and the driving force can be suppressed from entering the optical path, and the cleanliness in the optical path can be improved.

(7) In the exposure apparatus 10, the housing 82D has a second fly-eye lens system which constitutes a part of an illuminance uniforming mechanism for equalizing the illuminance distribution of the pulsed ultraviolet light on the reticle R. 28Fa is mounted. The housing 82D itself is moved by the housing driving mechanism 158 along the optical axis of the pulsed ultraviolet light. For this reason, by moving and adjusting the housing 82D to which the second fly-eye lens system 28Fa is attached along the optical axis direction of the pulsed ultraviolet light, the illuminance distribution of the pulsed ultraviolet light can be easily made uniform.

(8) In the exposure apparatus 10, the housing 82D is provided with an urging mechanism 160 for urging the entire housing 82D along the optical axis direction of the pulsed ultraviolet light against its weight. I have. For this reason, in a state where the housing 82D is urged in the antigravity direction along the optical axis direction of the pulsed ultraviolet light by the urging mechanism 160, the housing 82D is not biased by the housing driving mechanism 158. It can be easily and stably moved along the optical axis direction.

(9) In the exposure apparatus 10, an aperture plate supporting member 140 is provided on the aperture stop base 124 so as to rollably contact the aperture stop plate 128. For this reason, the aperture stop plate 128 having the notch 134 can be stably supported by the aperture plate support member 140 without any deviation, and the stability of the aperture stop plate 128 during rotation can be improved. .

(10) In the exposure apparatus 10, a plurality of aperture plate support members 140 for supporting the aperture stop plate 128 are provided. The notch 134 of the aperture stop plate 128
When the aperture stop plate 128 is disposed at an arbitrary circumferential position, the aperture stop plate 128 has at least three stop plate support members 140.
It has come to be supported by. For this reason, even when the aperture stop plate 128 having a partially notched disk shape is arranged at any rotational position, the aperture stop plate 128 can be stably supported by at least three aperture plate support members 140. Thus, the stability of the aperture stop plate 128 during rotation can be further improved.

(Modification) The embodiment of the present invention may be modified as follows. In the above embodiment, the aperture stop mechanism 28G1 may be housed in the housing 82D with the iris stop mechanism 28G2 arranged at the top and the iris stop mechanism 28G2 at the bottom.

In the above embodiment, when the iris diaphragm mechanism 28G2 is disposed on the pupil plane of the illumination optical system IOP, the aperture stop plate 128 is rotated so that the notch 134 is disposed on the optical path of the pulsed ultraviolet light. It has become so. On the other hand, for example, the aperture stop plate 128 may be slid and moved out of the optical path of the pulsed ultraviolet light. In this case, the aperture stop plate 128 does not necessarily need to be formed to have a partially cut-out disk shape in which the plurality of stops 136A to 136E and the cutouts 134 are arranged in the circumferential direction. 136E may be formed in a planar polygonal plate shape arranged in one-dimensional direction or two-dimensional direction.

In the above embodiment, the drive shaft 32a of the aperture switching motor 32 is brought into contact with the iris diaphragm base 126 of the iris diaphragm mechanism 28G2, and the iris diaphragm mechanism 28G
The second iris stop base 126 and the aperture stop base 124 of the aperture stop mechanism 28G1 may be integrally moved in the optical axis direction of the pulsed ultraviolet light.

In the above embodiment, a plurality of aperture plate support members 140 are rotatably mounted on the aperture stop plate 128 side, and these aperture plate support members 140 are rotatably mounted on the aperture stop base 124. The aperture stop plate 128 may be configured to be supported by being in contact therewith.

In the above embodiment, another member such as a spring member may be provided as an urging mechanism for urging the housing 82D in the optical axis direction of the pulsed ultraviolet light against the weight. In the above-described embodiment, in addition to the aperture stop mechanism 28G1 and the iris stop mechanism 28G2, another stop mechanism may be provided in parallel as the plurality of stop mechanisms.

In the above embodiment, the aperture stop mechanism 28G1 and the iris stop mechanism 28 are used as the plurality of stop mechanisms.
Instead of G2, another aperture mechanism may be provided. Even when the configuration is changed as described above, substantially the same effects as the effects in the above-described embodiment can be obtained.

The entire exposure apparatus can be embodied with the following modifications. In the embodiment, the ArF excimer laser light source, the KrF excimer laser light source, or the F2 laser light source is used as the light source. However, the present invention is not limited to this. For example, a Kr2 laser light source having a wavelength of 146 nm is used. A vacuum ultraviolet light source such as an Ar2 laser light source having a wavelength of 126 nm may be used. In such a case, it is possible to further improve the resolving power by pulsed ultraviolet light having a shorter wavelength, and to perform exposure with higher precision.

In the above embodiment, a fly-eye lens is used as an optical integrator (homogenizer). However, a rod integrator may be used instead. In an illumination optical system using a rod integrator, the rod integrator is arranged so that its exit surface is substantially conjugate with the pattern surface of the reticle R. Blinds 28
The movable blade BL of J is arranged. Therefore, this illumination optical system is divided into two parts by the rod integrator,
As in the previous embodiment, the movable reticle blind is provided in the first part where the rod integrator is arranged,
The fixed blind is provided in the second part fixed to the main body column. An illumination optical system using a rod integrator is disclosed in, for example, US Pat. No. 5,675,401. Combine a fly-eye lens with a rod integrator or use two rods
Integrators may be arranged in series to form a double optical integrator.

For example, even in the case of an exposure apparatus that uses ultraviolet light as in the above-described embodiment, a reflection system including only a reflection optical element as a projection optical system, or a catadioptric system including a reflection optical element and a refractive optical element ( Catadioptric system) may be employed. Here, as the catadioptric projection optical system, for example, Japanese Patent Application Laid-Open No. Hei 8-171504 (and corresponding US Pat. No. 5,668,672),
And a catadioptric system having a beam splitter and a concave mirror as reflective optical elements, as disclosed in JP-A-10-20195 (and corresponding US Pat. No. 5,835,275); No. 3,346,695 (and corresponding US Pat. No. 5,689,377).
And Japanese Patent Application Laid-Open No. 10-3039 (and corresponding US Patent Application No. 873,605 (filing date: 1).
For example, a catadioptric system having a concave mirror or the like can be used as a reflective optical element without using a beam splitter.

In addition, a plurality of refractive optical elements and two mirrors (a primary mirror which is a concave mirror and a refractive element) disclosed in JP-A-10-104513 (and US Pat. No. 5,488,229). Or a sub-mirror which is a back mirror in which a reflection surface is formed on the side opposite to the incident surface of the plane-parallel plate) and an intermediate image of a reticle pattern formed by the plurality of refractive optical elements. A catadioptric system that re-images on the wafer by the primary mirror and the secondary mirror may be used. In this catadioptric system, a primary mirror and a secondary mirror are arranged following a plurality of refractive optical elements, and illumination light is reflected through a part of the primary mirror in the order of a secondary mirror and a primary mirror. Part to reach the wafer.

The catadioptric projection optical system includes:
For example, having a circular image field and the object side,
Alternatively, a reduction system may be used in which both the image plane side is telecentric and the projection magnification is 1/4 or 1/5. Further, in the case of a scanning exposure apparatus having this catadioptric projection optical system, the irradiation area of the illumination light is substantially centered on its optical axis within the visual field of the projection optical system, and is substantially in the scanning direction of the reticle or wafer. It may be of a type defined as a rectangular slit extending along a direction orthogonal to the direction. According to a scanning apex type exposure apparatus having such a catadioptric projection optical system, a fine pattern of about 100 nm L / S pattern can be formed on a wafer with high precision even when, for example, F2 laser light having a wavelength of 157 nm is used as exposure illumination light. Can be transferred to

As the vacuum ultraviolet light, ArF excimer laser light, F2 laser light, or the like is used. In the infrared region oscillated from a DFB semiconductor laser or a fiber laser,
Alternatively, a single-wavelength laser beam in the visible region may be amplified by, for example, a fiber amplifier doped with erbium (or both erbium and yttrium), and a harmonic converted to ultraviolet light using a nonlinear optical crystal may be used. .

For example, the oscillation wavelength of a single-wavelength laser is set to 1.
When the wavelength is in the range of 51 to 1.59 μm, the generated wavelength is 18
An eighth harmonic having a wavelength in the range of 9 to 199 nm or a tenth harmonic having a generation wavelength in the range of 151 to 159 nm is output. In particular, the oscillation wavelength is 1.544 to 1.553 μm.
m, an 8th harmonic having a generation wavelength in the range of 193 to 194 nm, that is, ultraviolet light having substantially the same wavelength as the ArF excimer laser light is obtained, and the oscillation wavelength is set to 1.57.
When it is within the range of 1.58 μm, the generated wavelength is 157 to
The tenth harmonic within the range of 158 nm, that is, ultraviolet light having substantially the same wavelength as the F2 laser light is obtained.

The oscillation wavelength is set to 1.03 to 1.12 μm
, A 7th harmonic whose output wavelength is in the range of 147 to 160 nm is output.
When the wavelength is in the range of 099 to 1.106 μm, a 7th harmonic having a generated wavelength in the range of 157 to 158 μm, that is, ultraviolet light having substantially the same wavelength as the F2 laser light is obtained. In this case, as the single-wavelength oscillation laser, for example, an ytterbium-doped fiber laser can be used.

Glass substrates or silicon for manufacturing reticles or masks used not only for microdevices such as semiconductor elements, but also for optical exposure apparatuses, EUV exposure apparatuses, X-ray exposure apparatuses, electron beam exposure apparatuses, etc. The present invention is also applicable to an exposure apparatus that transfers a circuit pattern onto a wafer or the like. Here, a transmissive reticle is generally used in an exposure apparatus using DUV (far ultraviolet) light or VUV (vacuum ultraviolet) light, and quartz glass is used as a reticle substrate.
Quartz glass, fluorite, magnesium fluoride, quartz, or the like doped with fluorine is used. In a proximity type X-ray exposure apparatus or an electron beam exposure apparatus, a transmission mask (stencil mask, membrane mask) is used.
And a silicon wafer or the like is used as a mask substrate.

Of course, not only for an exposure apparatus used for manufacturing a semiconductor element, but also for an exposure apparatus for transferring a device pattern onto a glass plate and a thin-film magnetic head used for manufacturing a display including a liquid crystal display element and the like. The present invention can also be applied to an exposure apparatus used for transferring a device pattern onto a ceramic wafer, an exposure apparatus used for manufacturing an image pickup device (such as a CCD), and the like.

In the above embodiment, the case where the present invention is applied to the scanning stepper has been described. However, the pattern of the mask is transferred to the substrate while the mask and the substrate are stationary, and the substrate is sequentially moved in steps. The present invention is also suitable for a step-and-repeat type reduction projection exposure apparatus for causing a mask and a substrate to be in close contact with each other without using a projection optical system to transfer a mask pattern to the substrate. Applicable.

Semiconductor devices have device functions
A step of performing performance design, a step of manufacturing a reticle based on this design step, a step of manufacturing a wafer from a silicon material, a step of transferring a reticle pattern to the wafer by the exposure apparatus of the above-described embodiment, and a step of assembling a device (dicing Process, including a bonding process, a package process, and an inspection process.

[0131]

As described above in detail, according to the first aspect of the present invention, the structure is simple and a plurality of aperture mechanisms can be easily used as needed.

According to the second and third aspects of the present invention, in addition to the effects of the first aspect, an iris diaphragm mechanism and an aperture diaphragm mechanism are provided for controlling a pattern on a mask. It can be easily switched and selectively used for the Fourier transform plane or its vicinity.

According to the fourth aspect of the present invention, in addition to the effects of the second or third aspect, even when the iris diaphragm is arranged in the optical path, The aperture stop plate does not block the path of the energy beam.

According to the fifth aspect of the present invention, in addition to the effect of the fourth aspect of the present invention, the aperture stop plate can easily move in and out of the optical path. In addition, when the iris diaphragm is arranged in the optical path, the aperture diaphragm does not block the path of the energy beam.

According to the sixth aspect of the present invention, in addition to the effects of the first aspect of the present invention, impurities such as oil generated in the aperture driving mechanism and the transmission portion of the driving force are reduced.
It is possible to suppress entry into the optical path and improve the cleanness in the optical path.

According to the seventh aspect of the present invention, in addition to the effects of the sixth aspect, the housing in which a part of the illuminance uniforming mechanism is mounted can be mounted on the optical axis of the energy beam. By adjusting the movement along the direction, the illuminance distribution of the energy beam can be easily made uniform.

According to the eighth aspect of the present invention, in addition to the effect of the seventh aspect, the housing is urged in the direction of gravity along the optical axis of the energy beam. In this state, the housing can be easily and stably moved along the optical axis direction without any deviation.

[Brief description of the drawings]

FIG. 1 is a side view schematically showing an overall configuration of an exposure apparatus according to an embodiment.

FIG. 2 is a cross-sectional view showing a holding configuration of each optical unit in the entire second partial illumination optical system and a part of the first partial illumination optical system in the illumination optical system of FIG.

FIG. 3 is a cross-sectional view illustrating a detailed configuration of the aperture mechanism of FIG. 2;

FIG. 4 is a plan view of an aperture stop mechanism in the stop mechanism of FIG. 3;

FIG. 5 is a plan view of an iris diaphragm mechanism in the diaphragm mechanism of FIG. 3;

[Explanation of symbols]

10 Exposure device, 12 Light source as energy beam source, 28Fa Second fly-eye lens system constituting a part of illuminance distribution uniforming mechanism, 28G ... Aperture mechanism, 28G1 ...
Aperture stop mechanism, 28G2 ... iris stop mechanism, 32 ... Aperture switching motor constituting a switching mechanism and a base driving mechanism, 82
D: housing, 112: light path chamber forming an optical path area, 114: accommodation chamber forming an outer area, 124: aperture stop base, 126 ...
Iris diaphragm base, 128: aperture diaphragm plate, 134: notch as aperture, 136A to 136E: aperture diaphragm as diaphragm, 138: aperture diaphragm motor as diaphragm drive mechanism, 144: rotation constituting transmission unit Pulleys, 146: drive pulleys constituting a transmission unit, 150A, 150B: connection wires constituting a transmission unit, 152: iris diaphragm motor as a diaphragm drive mechanism, 158 ... housing movement motor as a housing drive mechanism, Reference numeral 160 denotes an air cylinder constituting an urging mechanism, IOP denotes an illumination optical system, and R denotes a reticle as a mask.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03F 7/20 521 G03F 7/22 H 7/22 H01L 21/30 515D

Claims (8)

[Claims] 1. An exposure apparatus having an illumination optical system for illuminating a mask on which a predetermined pattern is formed by an energy beam emitted from an energy beam source, wherein the illumination optical system illuminates the mask. A plurality of diaphragm mechanisms for changing the illumination shape of the mask, and a switching mechanism for moving the plurality of diaphragm mechanisms in the direction of the optical axis of the energy beam and switching and disposing the diaphragm mechanism on or near a Fourier transform plane relating to the pattern of the mask. An exposure apparatus comprising: 2. An iris diaphragm mechanism having an iris diaphragm for changing a diameter of an aperture in an optical path of the energy beam substantially continuously, and an aperture having a predetermined opening shape in the optical path. 2. An aperture stop mechanism for disposing an aperture plate so as to be able to move back and forth, wherein the iris stop and the aperture stop plate are arranged at a predetermined interval in the optical axis direction. Exposure equipment. 3. An iris diaphragm base for holding the iris diaphragm, an aperture diaphragm base for holding the aperture diaphragm plate, and at least one of the iris diaphragm base and the aperture diaphragm base being irradiated with the light of the energy beam. The exposure apparatus according to claim 2, further comprising a base driving mechanism that moves in an axial direction. 4. The aperture stop plate is disposed in an optical path of the energy beam when the iris stop is disposed at or near a Fourier transform plane relating to the pattern of the mask, and has an opening larger than the optical path. 4. The exposure apparatus according to claim 2, wherein the exposure apparatus comprises a flat plate. 5. The exposure apparatus according to claim 4, wherein the aperture stop plate is formed of a plurality of apertures having different aperture diameters and a disk in which notches are arranged in a circumferential direction. apparatus. 6. A housing accommodating the plurality of aperture mechanisms and defining an optical path region including an optical path through which the energy beam passes airtightly from an outer region, and a housing disposed outside the housing, 2. The apparatus according to claim 1, further comprising: an aperture driving mechanism that drives the plurality of aperture mechanisms in the housing; and a transmission unit that transmits a driving force of the driving mechanism to each of the aperture mechanisms via the housing. Exposure equipment. 7. A part of an illuminance equalizing mechanism for equalizing an illuminance distribution of the energy beam on the mask is mounted on the housing, and the housing itself is moved along an optical axis direction of the energy beam. 7. The exposure apparatus according to claim 6, further comprising a housing driving mechanism for moving the exposure apparatus. 8. The device according to claim 7, wherein the housing has an urging mechanism for urging the entire housing against the weight thereof along the optical axis direction of the energy beam. Exposure apparatus according to the above.