JP2000208407A - Aligner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aligner, having little decrease in illumination non- uniformity in illumination and excellent optical characteristics, without increase in size and cost. SOLUTION: The device body 11, where a wafer W is exposed through a reticle R inadiated with an illumination light, is housed in a temperature adjusting chamber 12. The outside air of the temperature adjusting chamber 12 is brought into a duct 24 while the air is being cleaned by a filter 25 by operating a fan 27, temperature, etc., is adjusted by a temperature adjuster 28, and the air is fed into the adjusting chamber 12 by a fan 29 while the air is being cleaned by a filter 26. The air passes through the chamber 12, introduced into the duct 24 through an exhaust hole 24d and circulated. On the down stream side of the fan 27, one end of a pipe line 20 is arranged, and the other end of the pipe line 20 is connected to the sub-chamber 15 where an illumination optical system is housed. A pump 22 is operated, and the air, which is cleaned by the filter 25, is fed under pressure into the sub-chamber 15.

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 for transferring a mask pattern onto a substrate in a lithography process for manufacturing, for example, a semiconductor device, a liquid crystal display device, or a thin film magnetic head.

[0002]

2. Description of the Related Art For example, in an exposure apparatus such as a stepper used for manufacturing a semiconductor device, in order to cope with an improvement in the degree of integration and fineness of the semiconductor device, it is particularly required to increase the resolution. The resolution is
Since it is almost proportional to the wavelength of the illumination light, the exposure wavelength has been gradually shortened conventionally. That is, the illumination light is changed from the visible g-line (wavelength 436 nm) of the mercury lamp to the ultraviolet i-line (wavelength 365 nm), and recently, KrF excimer laser light (wavelength 248 nm) has been used. .

[0003] Incidentally, in the future, ArF excimer laser light (wavelength 193 nm), _{F 2} laser beam (wavelength 157n
Although the use of m) and the like has been studied, it is expected that their practical use as mass production machines will be further advanced. This is because, in a wavelength range of about the ArF excimer laser beam or less, that is, in a vacuum ultraviolet range (VUV) of about 200 nm or less, absorption by oxygen in the air occurs, and ozone is generated to lower light transmittance. This is because special measures against the inability to use ordinary quartz glass as an optical element or the like need to be taken, and the technology for that is not sufficiently established.

[0004] Therefore, as a mass production machine, the wavelength of 200 nm
Exposure apparatuses that use illumination light of a certain degree or more are considered to be the mainstream for the time being, and technical development of such exposure apparatuses is important.

Here, in an exposure apparatus using illumination light having a wavelength of about 200 nm or more, impurity gases such as a sulfuric acid component, a nitric acid component, ammonia, amines, and siloxanes present in an optical path of the illumination light are subjected to photochemical reaction. It changes into a substance such as ammonium sulfate or ammonium nitrate and adheres to the surface of the optical element due to, for example, causing the transmittance or reflectance of the optical member to decrease, or deteriorating the uniformity of the illuminance distribution of the illumination light. .

For this reason, conventionally, the exposure apparatus main body is housed in a temperature control chamber which covers the entirety of the exposure apparatus, and the inside of the temperature control chamber is circulated while purifying the internal air through a filter or the like. Is being introduced into the temperature control chamber while purifying external air from outside through a filter or the like.

[0007] Further, a space including an optical path of the illumination light is shielded by a cover or the like, and an inert gas such as nitrogen gas having a high purity is poured into the shielded space.

[0008]

However, in the above-mentioned prior art, the atmosphere of the optical element (optical system) is made to be the atmosphere of purified air so that the optical element is not contaminated. Because the space that must be filled with air is large, outside air (unclean air) that has entered through a gap or the like without passing through the predetermined air intake of the temperature control chamber may be mixed into the purified air. was there. In addition, since the purified air flows relatively large in the temperature control chamber, the purified air may not reach every corner of the optical path of the illumination light, and the illuminance of the illumination light may be reduced or uneven. Could not be prevented sufficiently.

A device for supplying an inert gas such as nitrogen gas to a part of the optical path of the illumination light as a shielded space, which does not have the above-mentioned problem, is provided. However, there is a problem that the size of the apparatus is increased and the cost is increased, and the inert gas is generally expensive and the operation cost is high.

A part of the optical path of the illumination light is used as a shielding space, and an air supply device having a purifying device or the like is provided separately from the purifying device for supplying clean air into the chamber. Although it is conceivable to supply air, it is only possible to reduce the operating cost due to the use of air, and it is unavoidable to increase the size and cost of the device.

[0011] The present invention has been made in view of the above, and without increasing the size and cost of the apparatus,
An object of the present invention is to provide an exposure apparatus having excellent optical characteristics with less decrease in illuminance and deterioration in uniformity of illuminance distribution.

[0012]

Means for Solving the Problems In the following description, in order to facilitate understanding, each constituent element of the present invention will be described with reference numerals shown in the drawings of the embodiments. The constituent elements of the invention are not limited by these reference numerals.

An exposure apparatus according to the present invention provides illumination light (IL)
An exposure apparatus for exposing a photosensitive substrate (W) through a mask (R) irradiated with a chamber (12) that entirely covers an exposure apparatus body (11); and purifying air in the chamber or Purifying means (25, 26) for purifying air outside the chamber and introducing the air into the chamber; and shielding means (15) for forming a space shielded from the space in the chamber on at least a part of an optical path of the illumination light. ) And air supply means (30) for supplying the air purified by the purification means into the space defined by the shielding means.

According to the present invention, the space including at least a part of the optical path of the illumination light is shielded by the shielding means, and the clean air (the air inside or outside the chamber) purified by the purifying means is supplied to the shielded space. Since the air is supplied via the air supply means, clean air is distributed to the details of the optical path of the illumination light, and unclean outside air introduced from a gap in the chamber is prevented from reaching the optical path of the illumination light. You. Therefore, it is possible to prevent impurities and the like from adhering to the surface of the optical element, to sufficiently prevent the illuminance of the illumination light from being reduced and to cause the illuminance unevenness, and to improve the optical characteristics.

Further, the air purified by the purifying means for purifying the air inside or outside the chamber is supplied by the air supply means into the shielded space by the shielding means. This eliminates the need for a separate air purifying means, which can simplify the device configuration and prevent the device from being enlarged.

Furthermore, since clean air is supplied into the shielded space, there are problems associated with the use of inert gas, such as an increase in operating costs and the necessity of taking special safety measures. Not even.

The air supply means (30) has one end disposed at or near the purifying means (first purifying means 25, 26) and the other end connected to the space (shielding space 15). (20, 21), intake means (22) interposed in the pipeline for taking in the air purified by the purification means, and second purification means interposed in the pipeline. By doing so, the air highly purified by the first and second purifying means can be supplied to the optical path of the illumination light, so that the optical characteristics can be further improved. .

The shielding position of the optical path of the illumination light by the shielding means is not particularly limited, and may be a part or all. For example, one of the plurality of optical elements may make the illuminance distribution of the illumination light uniform. Illuminance distribution uniformizing means (16)
And an illumination optical system for illuminating the mask with uniform illumination light is provided by the shielding means from the illuminance distribution equalizing means to the optical element (19) closest to the mask. Can be configured to block the optical path between the two. When a projection system (PL) for projecting an image of the pattern from the mask illuminated by the illumination light onto the photosensitive substrate is provided, the shielding unit includes at least an optical path in the projection system. It may be configured to form a space partially shielded from the space in the chamber.

The purifying means (first purifying means) or the second purifying means is provided for removing contaminants (substances that affect optical characteristics) contained in air inside or outside the chamber to be removed and separated. Suitable ones can be used and are not particularly limited, and for example, ones including an activated carbon filter or an ion exchange filter can be employed.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. FIG. 1 shows a schematic configuration of a projection exposure apparatus according to the present embodiment. A clean room (not shown) is installed in the semiconductor manufacturing factory, and the projection exposure apparatus is housed and installed in this clean room. The inside of the clean room is air-conditioned so as to have a predetermined temperature and humidity.

In this projection exposure apparatus, a temperature control chamber 12 containing an exposure apparatus main body 11 therein, a light source chamber 13 containing a light source for emitting illumination light, and a light source chamber 13
Connection chamber 1 that houses an optical element and the like for introducing illumination light emitted from a light source inside the temperature control chamber 12.
4 and a sub-chamber 15 that accommodates an illumination optical system installed inside the temperature control chamber 12.

First, the box-shaped light source chamber 13 is installed on the floor of a clean room via a vibration isolator (not shown). Inside the light source chamber 13, a light source that emits KrF excimer laser light (oscillation wavelength 248 nm) as illumination light is housed.

A box-shaped temperature control chamber (environmental chamber) 12 having good airtightness is installed on the floor in a clean room adjacent to the light source chamber 13. In the temperature control chamber 12, a surface plate (not shown) is provided via a vibration isolator (not shown) for attenuating vibration from the floor, and the exposure apparatus main body 11 is mounted on the surface plate.

The connection chamber 14 is a highly airtight chamber for housing an optical element and the like for optically connecting the light source chamber 13 to the temperature control chamber 12. It is erected between them. Here, the optical element refers to a beam matching unit (BMU) including a movable mirror or the like for positionally matching an optical path with the exposure apparatus main body 11, a variable dimmer described later, a beam shaping optical system, and the like. It is. In addition, BM
U may be located in the light source chamber 13. A part of the connection chamber 14 extends to the inside of the temperature control chamber 12.

In order to keep clean air, the following items must be considered. When the connection chamber 12 is manufactured by the die-casting method, the surface (including the inner surface and the outer surface) of the connection chamber has depressions such as a casting cavity. Therefore, when painting or the like is performed to fill a nest or the like, it is preferable to perform painting (for example, a fluororesin or the like) with less degassing. Further, the connection chamber 12 may be manufactured using unpainted solid stainless steel (SUS). However, when the connection chamber 12 is used as it is, the connection chamber 12 is previously cleaned by ultrasonic cleaning, a solvent, or the like. In this state in which degassing from the connection chamber 12 is suppressed, clean air is supplied into the connection chamber 12 as in the present embodiment, or if nitrogen gas or the like is previously introduced into the connection chamber 12. It may be filled with an active gas. Thus, the connection chamber 1
When an inert gas or clean air is supplied into the inside 2, it is desirable that the structure of the connection chamber 12 be a double structure to improve airtightness. Similarly, the sub-chamber 15 may have a double structure. Further, the fan 29 and the temperature controller 28 disposed in the duct 24 clean each of the constituent components in advance (ultraviolet cleaning, ultrasonic cleaning, or immersing in a solvent or the like). In addition, it is necessary to suppress adhered contaminants and degassing from the parts themselves.

Further, the power supply wiring existing in the temperature control chamber 12 and the sub-chamber 15 is covered (for example, vinyl chloride).
By applying a fluororesin (Teflon (registered trademark) material) coating or winding an aluminum foil or the like, organic gas generated from the coating can be suppressed. Further, the coating itself may use a wiring made of fluororesin.

Further, since the pipes 20 and 21 are formed of a material having a good thermal conductivity (eg, aluminum), the pipes 20 and 21 are adapted to the temperature in the chamber 12. There is no temperature difference between the air flowing through the inside 21.

When the pipes 20, 21 are made of aluminum or the like, the outer and inner peripheral surfaces thereof may be coated with a fluororesin (Teflon material), or the pipes themselves may be made of a fluororesin.
It may be formed of stainless steel. By doing so,
Organic substances are prevented from being mixed into the clean air in the chamber.

As described above, Teflon material, stainless steel, and the like are the most suitable materials to be used for piping, wiring, and the like in the present embodiment, because the degassing of organic substances and the like from itself is small. It is needless to say that Teflon material or stainless steel may be used for the duct and each chamber.

The sub-chamber 15 is installed in the temperature control chamber 12, and is connected to the temperature control chamber 1 of the connection chamber 14.
2 are connected. Most of the illumination optical system is housed in the sub-chamber 15.

First, at the time of exposure, the illumination light IL as ultraviolet pulse light having a wavelength of 248 nm emitted from the laser light source in the light source chamber 13 reaches the BMU in the connection chamber 14. In the connection chamber 14, the illumination light IL enters the sub-chamber 15 via a variable attenuator as an optical attenuator (not shown) and a beam shaping optical system including a lens system.

In the sub-chamber 15, an optical integrator (homogenizer) 16, such as a fly-eye lens or a rod integrator, for uniforming the illuminance distribution,
An illumination optical system including a reticle blind (variable field stop) 17, a reflecting mirror 18, a main condenser lens 19, and the like is accommodated. On the exit surface of the optical integrator 16, an illumination system aperture stop system (not shown) for variously changing illumination conditions is arranged.

The illumination light I emitted from the optical integrator 16 and having passed through a predetermined aperture stop in the aperture stop system.
L enters a fixed illumination field stop (fixed blind) having a slit-shaped opening in the reticle blind 17 via a condenser lens system (not shown). Further, in the reticle blind 17, a movable blind for varying the width of the illumination visual field in the scanning direction is provided separately from the fixed blind. The illumination light IL shaped into a slit by the fixed blind of the reticle blind 17 passes through an imaging lens system (not shown), a reflection mirror 18 and a main condenser lens 19, and is formed into a slit shape on the circuit pattern area of the reticle R. Is illuminated with a uniform intensity distribution.

A main pipe 20 is provided in a space formed between various optical elements or optical devices in the sub-chamber 15.
Are connected, and clean air is supplied under pressure, as described later. An open / close valve controlled by a control system can be provided in the main pipe 20 and each branch pipe 21, and a space for supplying clean air can be selected by selectively opening / closing each open / close valve. It may be. A fan (or pump) 22 is interposed in the vicinity of the upstream side of the branch of the main pipe 20. These main pipe 20, branch pipe 21 and fan 22
Constitutes the air supply means 30.

Under the illumination light IL, the image of the circuit pattern in the illumination area of the reticle R is transferred to the slit-like exposure area of the resist layer on the wafer W via the projection optical system PL. The exposure region is located on one of the plurality of shot regions on the wafer W. The projection optical system PL of the present embodiment is a dioptric system (refractive system), but the projection optical system PL is a catadioptric system (catadioptric system) or a reflective system, and the illumination light in the projection optical system PL is used. The transmittance of the IL may be increased. In the description below, the Z axis is taken in parallel with the optical axis of the projection optical system PL, the X axis is taken in a plane perpendicular to the Z axis, parallel to the plane of FIG. 1, and the Y axis is taken perpendicular to the plane of FIG. .

At this time, the reticle R is held by suction on a reticle stage (not shown), and the reticle stage can move at a constant speed in the X direction (scanning direction) on a reticle base (not shown), and in the X and Y directions. , So that it can be finely moved in the rotation direction. The two-dimensional position and rotation angle of the reticle stage (reticle R) are controlled by a drive control unit (not shown) equipped with a laser interferometer.

On the other hand, the wafer W is held by suction on a wafer holder (not shown), the wafer holder is fixed on a wafer stage 23, and the wafer stage 23 is placed on a surface plate. The wafer stage 23 controls the focus position (position in the Z direction) and the tilt angle of the wafer W by an autofocus method so that the surface of the wafer W is aligned with the image plane of the projection optical system PL, and the wafer stage 23 is moved in the X direction. , And stepping in the X and Y directions.

The two-dimensional position and rotation angle of the wafer stage 23 (wafer W) are also controlled by a drive control unit (not shown) equipped with a laser interferometer. At the time of scanning exposure, the reticle R moves in the + X direction (or -X direction) with respect to the illumination area of the illumination light IL via the reticle stage.
In synchronization with the scanning at r, the speed of the wafer W in the −X direction (or + X direction) α · Vr (α is the projection magnification from the reticle R to the wafer W) with respect to the exposure area via the wafer stage 23 ).

On the ceiling surface and side surface of the temperature control chamber 12,
A duct 24 for flowing air is provided integrally. An outside air intake is provided at one end 24a of the duct 24, and the outside air intake is provided with the chamber 1
A plurality of filters 25 (purification means) suitable for removing and separating contaminants affecting the optical characteristics contained in the air outside (in the clean room) are attached. Further, an air supply port is formed in a portion 24b of the duct 24 which is located on the ceiling surface of the temperature control chamber 12 and is joined to the temperature control chamber 12, and an air supply port is formed in the air supply port. A plurality of filters 26 (purification means) suitable for removing and separating contaminants affecting the optical characteristics included in the filter are mounted.

In this embodiment, the filters 25, 26
A gas removal filter for removing and separating gas components of pollutants and a particle filter for removing and separating solid components (particles and the like) of pollutants are attached. As the gas removal filter, for example, an activated carbon filter, an ion exchange filter, or the like can be used. However, the filters 25 and 26 are appropriately selected according to the substance to be removed / separated. As the ion exchange filter, for example, a zeolite filter can be used. Each of the filters 25 and 26 may be a single filter or a larger number.

With such filters 25 and 26,
Various substances including silicon-based organic substances such as siloxane (a substance having an Si-O chain as an axis) and silazane (a substance having an Si-N chain as an axis), hydrocarbons, ammonium ions, and sulfate ions existing in the air. Of contaminants are removed. In addition, a substance called "cyclic siloxane" in which Si-O chains are looped, which is one of the siloxanes, is contained in a silicon-based adhesive, a sealing agent, a paint, etc. used in a projection exposure apparatus, This occurs as degassing due to aging. Cyclic siloxane easily adheres to the surface of a wafer or an optical element (such as a lens), and when exposed to ultraviolet light, is oxidized to become a SiO ₂ -based cloudy substance on the optical element surface.

As the silazane, there is HMDS (hexamethyldisilazane) used as a pretreatment agent in a resist coating step. HMDS reacts with water to change (hydrolyze) into a substance called silanol. Silanol easily adheres to the surface of a wafer, an optical element, or the like, and is further oxidized when exposed to ultraviolet light to become a SiO ₂ -based cloudy substance on the optical element surface. In addition, silazane generates ammonia by the above-mentioned hydrolysis, and when this ammonia coexists with siloxane, the surface of the optical element is further easily clouded.

Further, in addition to the above-mentioned silicon-based organic substances, plasticizers (phthalsan ester, etc.), flame retardants (phosphoric acid, chlorine-based substances) and the like are also generated as degassed wires and plastics. In the form, these plasticizers and flame retardants are also removed by the filters 25 and 26.

A portion 24 near the outside air intake of the duct 24
A fan (or pump) 27 for blowing air is provided near the downstream side of the filter 25 of FIG.
Is driven by a motor (not shown), so that the outside air is sucked in from the outside air intake through various filters 25. A temperature controller 28 is provided near an upper portion of a portion 24c of the duct 24 located on the side surface of the temperature control chamber 12. The temperature controller 28 is an air conditioner that adjusts the temperature and humidity of the air flowing through the duct 24 to predetermined values.

The duct 24 is further above the temperature controller 28 in order to ascend the side portion 24c of the duct 24 and to blow air controlled by the temperature controller 28 to the ceiling portion 24b of the duct 24 while blowing the air. Fan (or pump) 29 is provided. A portion of the duct 24, which is relatively lower than a portion 24 c located on the side surface of the temperature control chamber 12 and is joined to the temperature control chamber 12, is for introducing air in the temperature control chamber 12 into the duct 24. An air outlet 24d is formed.

The air supplied into the temperature control chamber 12 from the air supply port of the ceiling portion 24b of the duct 24 descends,
It flows in the vicinity of the sub-chamber 15, the reticle R, the projection optical system PL, the wafer W, and the like, and the side portion 24c of the duct 24
Is introduced into the duct 24 from the air outlet 24d of the air conditioner and circulated while being temperature-controlled and purified by the temperature controller 28 and the filter 26.

On the floor of the temperature control chamber 12, a main pipe (pipe or duct) 20 is laid.
An opening at one end of the main pipe 20 is disposed so as to point in the vicinity of the downstream side of the fan 27, and the other end of the main pipe 20 is branched into a plurality (three in the figure). It is connected to each space formed in the sub-chamber 15 accommodating the illumination optical system. A pump (or fan) 22 for blowing air is provided near the branch of the main pipe 20. By operating the fan 27 or the like, the clean air taken in from the outside air intake and purified through the various filters 25 is introduced into the main pipe 20 by operating the pump 22. And the main pipe 20
The air introduced therein is branched, flows through each branch pipe 21, and is pressurized and supplied to each space in the sub-chamber 15.

As described above, according to the present embodiment, the illumination optical system existing in the temperature control chamber 12 in the optical path of the illumination light IL is shielded by the sub-chamber 15 (shielding means).
Since clean air is pressurized and supplied into the sub-chamber 15, the clean air spreads to the details of the portion of the optical path of the illumination light IL existing in the sub-chamber 15. Adhesion to the surface of an optical element (a lens or a mirror) or the like constituting an illumination optical system is prevented, and it is possible to sufficiently prevent a decrease in illuminance of the illumination light IL and the occurrence of uneven illuminance, thereby improving optical characteristics. Can be.

In addition, the air in the clean room is taken into the sub-chamber 15 and is supplied to the filter 25.
The clean air purified by (purification means) is
Main pipe 20 and branch pipe 21 (air supply means 3
0), and the filter 25 is normally provided as a standard in an exposure apparatus in order to purify the air sent into the temperature control chamber 12. The optical characteristics can be improved without requiring a separate filter (purification means) for supplying clean air to the device, without complicating the device configuration and increasing the size of the device.

The pump 22 is omitted and the fan 27
Thus, clean air may be pressurized and supplied into the sub-chamber 15 via the main pipe 20 and the branch pipe 21.
With this configuration, the configuration of the air supply unit 30 can be further simplified, and the efficiency is improved.

Further, since the air supplied to the temperature control chamber 12 and the sub-chamber 15 is clean air, and the air is safe and free of charge, it is necessary to increase the operating cost and take special safety measures. There is no problem associated with the use of an inert gas.

It should be noted that a filter similar to or different from the filters 25 and 26 may be interposed in the main pipe 20 so as to further purify the air supplied to the sub-chamber 15. This further prevents contaminants from adhering to optical elements and the like in the sub-chamber 15 and further improves optical characteristics.

In the above embodiment, clean air is supplied into the sub-chamber 15 by the air supply means 30. However, separately or in addition to this, the light source chamber 13 and the connection chamber may be provided. Clean air can be supplied to one or both of the 14 by similar air supply means. In this case, each chamber 13, 1
Air supply means may be provided independently for each of the chambers 4 and 15 to supply clean air, or a single air supply means may be provided for each of the chambers 13, 14 and 15 and a branch pipe may be provided. You may make it increase and supply clean air.

The air is allowed to flow through the connection between the connection chamber 14 and the sub-chamber 15 so that clean air by the air supply means 30 is supplied to the connection chamber 14 via the sub-chamber 15. You may. The same applies to the light source chamber 13.

Further, the lens barrel holding each optical element and the like of the projection optical system PL is constructed in an airtight manner, and a space defined by each optical element and the like is similar to the air supply means 30. You may make it supply clean air with an air supply means. In this case, an airtight chamber is defined between the optical elements in the projection optical system PL, and air is supplied to the airtight chamber to control the pressure thereof, thereby adjusting the optical distance between the optical elements. In the case where a lens controller adapted to perform such operations is employed, clean air may be supplied to the lens controller by an air supply unit similar to the air supply unit 30.

Further, the space between the illumination optical system and the reticle R, the space between the reticle R and the projection optical system PL, and the space between the projection optical system PL and the wafer W are shielded from other spaces, and one or more of the respective spaces are air-sealed. You may make it supply clean air by the air supply means similar to the supply means 30.

In the above embodiment, the optical path from the optical integrator 16 as the illuminance distribution uniforming means to the main condenser lens 19 which is the optical element closest to the reticle R is formed as a shielding space by the sub-chamber 15. In this case, clean air is supplied by the air supply means 30, but some of the optical elements and the like are excluded therefrom, or further contained in the sub-chamber 15 including other optical elements and the like. Air supply means 30
May be supplied.

In the above embodiment, the end of the main pipe 20 constituting the air supply means 30 on the air introduction side is provided so as to be located downstream of the fan 27 near the outside air intake of the duct 24. However, it may be provided so as to be located near the downstream side of the temperature controller 28, near the downstream side of the fan 29, or near the downstream side of the filter 26.

FIG. 1 showing the above embodiment does not show other devices accommodated in the temperature control chamber 12 accommodating the exposure device main body 11, but the exposure device as a mass production machine is not shown. A wafer transfer system for transferring the wafer W;
The apparatus is provided with another device such as a reticle transport system for transporting the reticle R, and divides the inside of the temperature control chamber 12 to define a chamber for accommodating them, or a single or multiple chambers adjacent to the temperature control chamber 12. Install other chambers that make up the room,
In some cases, other devices such as a wafer transfer system and a reticle transfer system may be accommodated, and air purification and temperature control may be performed for each room or collectively for a plurality of rooms. In this case, the air introduction side end of the main pipe 20 of the air supply means 30 is arranged at or near the air purification means for each of the chambers so as to branch and supply clean air. Can also.

The present invention is not limited to the above-described embodiment, but may take various configurations without departing from the spirit of the present invention.

For example, in the above-described embodiment, an exposure apparatus employing a device that emits ArF excimer laser light (wavelength: 248 nm) as a light source has been described, but an exposure device that emits illumination light having a wavelength of about 200 nm or more. Then, the present invention can also be applied to an exposure apparatus using a device that emits illumination light of another wavelength.

In the above embodiment, the step
Although the description has been given of the reduction projection scanning exposure apparatus (scanning stepper) of the AND scan method, for example, the entire surface of the reticle pattern is irradiated with exposure illumination light while the reticle and the wafer are stationary, and the reticle is exposed. A step-up / repeat type reduction projection type exposure apparatus (stepper) for collectively exposing one section area (shot area) on a wafer to which a pattern is to be transferred, and an exposure apparatus such as a mirror projection type or a proximity type. The present invention can be applied to the same manner. Also, the projection optical system is not limited to the reduction optical system,
A 1: 1 optical system or a magnifying optical system may be used.

Further, a single-wavelength laser in the infrared or visible range oscillated from a DFB semiconductor laser or fiber laser is used as exposure illumination light, for example, a fiber amplifier doped with erbium (or both erbium and ytterbium). May be used, and a harmonic that is wavelength-converted to ultraviolet light using a nonlinear optical crystal may be used.

Further, a semiconductor device, a liquid crystal display,
Not only projection exposure equipment used for manufacturing thin-film magnetic heads and imaging devices (such as CCDs), but also projection exposure equipment that transfers circuit patterns to glass substrates or silicon wafers to manufacture reticles or masks The present invention can also be applied.

[0065]

According to the present invention, as described in detail above, since clean air is supplied to the optical path of the illumination light, impurities and the like are prevented from adhering to the surface of the optical element, and the illuminance of the illumination light is reduced. It is possible to sufficiently prevent the reduction and the nonuniformity of the illuminance distribution, and to improve the optical characteristics. Also,
Since the air purified by the purifying means for purifying the air inside and outside the chamber is branched and supplied into the shielded space by the shielding means, no separate air purifying means or the like for supplying air into the shielded space is required. To that extent, the configuration of the device can be simplified and the size of the device can be prevented from increasing. Further, since clean air is supplied into the shielded space, the operation cost is low and the operation is safe.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of a projection exposure apparatus according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 11 ... Exposure apparatus main body 12 ... Temperature control chamber 13 ... Light source chamber 14 ... Connection chamber 15 ... Subchamber (shielding means) 16 ... Optical integrator (illuminance distribution equalization means) 20 ... Main piping (pipe) 21 ... Branch pipe ( 22) Pump 24 ... Duct 25, 26 ... Filter (purification means) 27, 29 ... Fan 28 ... Temperature controller 30 ... Air supply means

Claims (6)

[Claims] 1. An exposure apparatus that exposes a photosensitive substrate through a mask irradiated with illumination light, a chamber that entirely covers an exposure apparatus main body, a purification unit that purifies air in the chamber, and the illumination light. Shielding means for forming a space shielded from the space in the chamber on at least a part of the optical path, and air supply means for supplying air purified by the purification means into the space by the shielding means. Exposure apparatus characterized by the above-mentioned. 2. An exposure apparatus for exposing a photosensitive substrate through a mask irradiated with illumination light, comprising: a chamber that entirely covers an exposure apparatus body; and purifying air outside the chamber and introducing the air into the chamber. A purifying unit; a shielding unit that forms a space shielded from a space in the chamber on at least a part of an optical path of the illumination light; and an air that supplies air purified by the purifying unit into the space defined by the shielding unit. An exposure apparatus comprising: a supply unit. 3. The air supply means has one end disposed at or near the purifying means, the other end connected to the space, and a purifier interposed in the duct and purified by the purifying means. 3. The apparatus according to claim 1, further comprising intake means for taking in air, and second purifying means interposed in said conduit.
3. The exposure apparatus according to claim 1. 4. An illumination optical system for illuminating the mask with uniform illumination light, wherein one of the plurality of optical elements is constituted by illuminance distribution equalizing means for uniformizing the illuminance distribution of the illumination light. 4. The exposure apparatus according to claim 1, further comprising a system, wherein the shielding unit uses an optical path from the illuminance distribution uniformizing unit to an optical element closest to the mask as a shielding space. 5. . 5. A projection system for projecting an image of a pattern from the mask illuminated by the illumination light onto the photosensitive substrate, wherein the shielding means is provided on at least a part of an optical path in the projection system. 4. The exposure apparatus according to claim 1, wherein the exposure apparatus forms a space shielded from a space inside the exposure apparatus. 6. The exposure apparatus according to claim 1, wherein the purifying unit or the second purifying unit includes an activated carbon filter or an ion exchange filter.