JPH11317343A - Aligner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aligner, wherein failures in exposure such as drop of illuminance due to the blooming of an optical material and pattern dislocation is eliminated. SOLUTION: For an aligner 1 which is provided with an air-conditioning device 9 and a light source 2 which emits a light of ultraviolet region, optical catalysts 13-15 are provided at least at a part of the region irradiated with the ultraviolet light, and an ionic material removing material 11 such as an absorbent and an ion-exchange fabric can be installed in an air flow channel within the exposure device 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus,
In particular, the present invention relates to an exposure apparatus that uses a light source that emits ultraviolet light such as a mercury lamp, an excimer laser, and a harmonic laser.

[0002]

2. Description of the Related Art A conventional semiconductor exposure apparatus will be described. The degree of integration of semiconductors has been getting finer every year,
It has become necessary to form the minimum line width of integrated circuits in submicron. To cope with this miniaturization, it is conceivable to (1) shorten the wavelength of a light source of a projection exposure apparatus for producing a semiconductor integrated circuit, and (2) to form a circuit by using a new type of resist called a chemically amplified type. ing. The use of a new type of resist will increase patterning, resolution,
This is because characteristics such as sensitivity are excellent. On the other hand, since this resist generally contains a resin (organic substance), an acid generator, a dissolution accelerator, a cross-linking agent, and the like, there is a concern that the resist may have an adverse effect.

Examples of the light source include a KrF excimer laser having a wavelength of 248 nm, an ArF excimer laser having a wavelength of 193 nm, a harmonic of Ti-sapphire, and a wavelength of 266 nm.
YAG laser with 4th harmonic and wavelength of 213nm
There is a fifth harmonic of the laser. Such short wavelength light,
When irradiating the above-mentioned chemically amplified resist, gaseous substances such as hydrocarbons (HC), H ₂ SO ₄ , NH
_3. Generates amine and causes fogging on the lens or mirror surface, which is the heart of the exposure apparatus. This not only causes a failure rate of the apparatus, but also causes a problem in long-time operation (practical operation). The generation of fogging on the surface of the lens or the mirror occurs because the generated gaseous substance causes a photochemical reaction due to short-wavelength light (short-wavelength light has high energy) and S
It is considered that it is converted into particulate matter such as iO ₂ and (NH ₄ ) ₂ SO ₄ .

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an exposure apparatus which eliminates an obstacle at the time of exposure, such as a decrease in illuminance due to clouding of an optical material and a pattern shift, in view of the above prior art. .

[0005]

According to the present invention, there is provided an exposure apparatus having an air conditioner and a light source which emits light in the ultraviolet region. A photocatalyst is provided in one part. Further, in the exposure apparatus of the present invention, an ionic substance removing material can be provided in the air flow path in the exposure apparatus.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention has been made based on the following six findings. That is, (1) NOx, SOx, and H as gaseous harmful components are contained in normal air (outside air).
There are acidic gases such as Cl, alkaline gases such as ammonia and amines, and organic gases called hydrocarbons (HC), and these filters in a current clean room cannot collect these gaseous harmful components. Therefore, these harmful gases are introduced into the clean room. (2) Until now, in advanced industries, removal of particulate matter has been sufficient in the past. However, higher quality and refinement of products (higher cost products have higher integration density, that is, finer ,
Higher precision) and will be strongly influenced by gaseous substances in the future.

(3) The above-mentioned gaseous harmful components are generated from work in a clean room or from components and equipment of a clean room. Even if the generated gas has an extremely low concentration, the clean room is a closed system. Since the air is confined (recently, a clean room has a high ratio of circulating air in terms of energy saving), the concentration gradually increases, and adheres to wafers, glass substrates, and base materials in the clean room, and has an adverse effect. The generation of harmful gases in the above clean room is described in H. Next, C will be described as an example. In a clean room environment in which at least a part is made of an organic substance (polymer resin), a trace amount of organic gas (HC) is generated from the organic substance, and a container (such as a wafer or a glass substrate) in the clean room space is generated. Raw materials, semi-finished products). That is, in the clean room space, at least a part of the organic material (eg,
Plastic container, packing material, sealing material, adhesive material, wall material, etc.), and a very small amount of organic gas is generated from the organic matter. For example, siloxane is generated from the sealing material, and phthalic acid ester is generated from the plastic material that is the material of the storage container.

(4) In the manufacturing apparatus, the gaseous harmful components cause a decrease in product yield. In the future, as products become more precise and finer, the effects of gaseous harmful components will be serious. (5) The gaseous harmful component which adheres to and adversely affects the substrate surface similarly adheres to the glass surface of the optical system in the exposure apparatus. (6) Among the gaseous harmful components, C is 0.05mW
It can be removed by placing a photocatalyst in a space where light of at least / cm ² exists. Further, the acidic gas and the alkaline gas can be removed by the adsorbent. In the above description, the degree of contamination of a substrate or a substrate such as glass can be represented by the contact angle of the substrate or the substrate. If the contamination is severe, the contact angle is large. Here, the contact angle is a contact angle of wetting by water, and indicates a degree of contamination of the substrate surface. That is,
When a hydrophobic (oil-based) contaminant adheres to the substrate surface, the surface repels water and becomes hard to wet. Then, the contact angle between the substrate surface and the water droplet increases. Therefore, the contamination degree is high when the contact angle is large, and low when the contact angle is small.

Next, the components of the present invention will be described.
First, the photocatalyst will be described. The photocatalyst is excited by light irradiation, Any material that can decompose C may be used. Any photocatalyst can decompose or convert organic gases (non-methane hydrocarbons) involved in increasing the contact angle into a form that does not contribute to the increase in the contact angle, or convert it into a stable form that does not affect the adhesion. May be. Usually, a photocatalyst is preferable because a semiconductor material is effective, easily available, and has good workability. In terms of effectiveness and economy, S
e, Ge, Si, Ti, Zn, Cu, Al, Sn, G
a, In, P, As, Sb, C, Cd, S, Te, N
i, Fe, Co, Ag, Mo, Sr, W, Cr, Ba,
Any of Pb, their compounds, alloys, or oxides is preferable, and these are used alone or in combination of two or more.

For example, the elements are Si, Ge, Se,
Compounds include AlP, AlAs, GaP, AlSb,
GaAs, InP, GaSb, InAs, InSb, C
dS, CdSe, ZnS, MoS ₂ , WTe ₂ , Cr ₂
Te ₃ , MoTe, Cu ₂ S, WS ₂ , and oxides such as TiO ₂ , Bi ₂ O ₃ , CuO, Cu ₂ O, ZnO, M
oO ₃ , InO ₃ , Ag ₂ O, PbO, SrTiO ₃ ,
BaTiO ₃ , Co ₃ O ₄ , Fe ₂ O ₃ , NiO and the like are available. Depending on the application destination, the photocatalyst can be formed on the metal surface by firing the metal material. As an example of this, Ti
There is a photocatalyst in which a material is fired at 1000 ° C. to form TiO _{2 on} the surface (Japanese Patent Application No. 9-273302). Further, in order to improve the photocatalytic action, Pt, A
A substance such as g, Pd, RuO ₂ , or Co ₃ O ₄ can be added for use. The addition of the substance is carried out by photocatalysis. C is preferred because the decomposition action is promoted. They are,
One type or a combination of two or more types can be used. Usually, the addition amount is 0.01% by weight to 10% by weight based on the photocatalyst.
Preliminary tests can be appropriately performed according to the type of the added substance, required performance, and the like, and an appropriate concentration can be selected.

As the method of addition, well-known means such as an impregnation method, a photoreduction method, a sputter deposition method, and a kneading method can be appropriately used. The photocatalyst can be installed in the exposure apparatus by fixing it to the flowing air, fixing it to the wall, or floating it in the air. For fixing the photocatalyst, the photocatalyst is coated, wrapped, or sandwiched in an appropriate material (base material) such as a plate, cotton, wire, fiber, mesh, honeycomb, film, sheet, or fiber. And may be used fixed in the unit. For example, the method can be performed by appropriately using a known additional means such as a sol-gel method, a sintering method, an evaporation method, a sputtering method, or a coating method on a ceramic, a fluororesin, or a glass material. In general, a fibrous, net-like, or honeycomb-like shape is preferred because of its low pressure loss. Examples are the addition of TiO ₂ to the glass fiber.

The non-methane hydrocarbon (HC) to be removed by the present invention causes contamination on the lens and mirror surface of the exposure apparatus even at a normal concentration in air. In the air,
Considerably many types of multicomponent H. C exists. Various H. C
Of the exposure apparatuses of the present invention cause contamination on the surfaces of lenses and mirrors. C is a contaminant on the surface of a wafer or a glass substrate, that is, H.C increases the contact angle. C is considered. In a clean room, about 0.5 to 1.5 ppm of H.sub. C exists. The present inventor has conducted intensive studies and as a result, using non-methane hydrocarbons as indicators,
It has been found that it is effective to remove this to 0.2 ppm or less, preferably 0.1 ppm or less by decomposition and treatment with a photocatalyst. That is, an organic gas (HC) that increases the contact angle of the substrate surface in a normal clean room can be said in common to a high molecular weight HC. C
And has a -CO, -COO bond (having hydrophilicity) as its structure. This H. C is a hydrophobic substance (H.C.) having a hydrophilic part (-CO, -COO bonding part).
C-C- part of the basic structure of C).

[0013] With reference to embodiments, the organic gas to increase the contact angle of the surface of the substrate such as a glass substrate in the conventional clean room, a high molecular weight of C ₁₆ -C ₂₀ H. C, for example, a phthalic acid ester and a higher fatty acid phenol derivative. These components have a chemical structure of —CO and —COO bonds (having hydrophilicity) in common.
The cause of these contaminated organic gases is a plasticizer, a release agent, an antioxidant, and the like of the polymer product, and the place where the polymer product exists is a source (see “Air Purification”, Vol. 1
No., p16-21, 1995). The details of the mechanism of treatment of these organic gases by the photocatalyst are unknown, but can be estimated as follows. That is, these organic gases are -C
The O and -COO bonds are hydrogen bonded to the OH groups on the surface of the wafer or glass, and the upper surface becomes a hydrophobic surface. As a result, the surface of the wafer or glass becomes hydrophobic, the contact angle increases, and a film is formed on the surface. Then, the adhesion of the film is weak.

When a photocatalyst is installed in an atmosphere in which an organic gas is present, first, the organic gas is adsorbed on the surface of the photocatalyst in the same manner as on the surface of a wafer or glass. The part is converted to another stable form by irradiation of the photocatalyst with light. As a result, the organic gas is in a stable form and does not adhere to the wafer or glass substrate, or does not exhibit hydrophobicity even if it adheres. The photocatalyst is installed and used in a part of the space in the exposure apparatus where light of 0.05 mW / cm ² or more exists. Examples of the installation location include a passage in the illumination system (FIG. 1) and a passage in the chamber (FIG. 1). The installation of the photocatalyst depends on the H.O. C concentration,
A preliminary test is appropriately performed according to the required performance, the concentration of the coexisting component, and the like.
A single location or a plurality of locations can be installed.

Next, the ionic substance removing material will be described. The ionic substance removing material is NOx, SOx, HCl,
It collects and removes ionic acidic gas such as HF and ionic alkaline gas such as ammonia and amine, and a known adsorbent (collecting material) or ion exchange fiber can be appropriately used. . In the use of the photocatalyst, it is preferable to collect and remove the ionic gas (substance) with the ionic substance removing material because the photocatalyst can be used stably for a long time (adsorption (adhesion) of the ionic substance to the photocatalyst surface)
This is preferable since performance degradation due to the above can be prevented.) Such adsorbents include NOx and S in clean rooms.
Any material can be used as long as it efficiently collects acidic gases such as Ox, HCl, and HF, and alkaline gases such as ammonia and amines to a low concentration.

As such adsorbents, there are silica gel, zeolite, alumina, activated carbon, and ion exchange fiber.
Among them, activated carbon and ion-exchange fiber are preferred because they are effective. As the activated carbon, an impregnated carbon such as an acid or an alkali can be used as appropriate depending on the trapping component (the type of the target gas). The shape of the adsorbent can be used in an appropriate shape, but is generally preferred to be filter-like, fibrous, mesh-like, or honeycomb-like because it is effective. The concentration of the above-mentioned acidic gas or alkaline gas in the clean room air is usually at least 10 ppb or more. For example, NOx
Is 10 to 50 ppb, SOx is 10 to 50 ppb, NH
₃ exists about 10 to 100 ppb. Normally, in a clean room, these gases are often generated due to work, and since the clean room air is circulated for energy saving, the concentration of at least one of the gaseous harmful components is reduced. The concentration is even higher.

[0017] As described above, the clean room air, but the acid gases and alkaline gases are present over many types (multi-component), in the present invention, SOx, NOx and / or NH ₃ as an indicator 5ppb or less, preferably It is usually effective to reduce to less than 1 ppb. Since the components and concentrations of the acidic gas and the alkaline gas differ depending on the use and the place of use, the components of the index can be appropriately determined in consideration of the components. In addition, the above SOx, NO
Since x and NH ₃ can be easily monitored (measured) at low concentrations, they can be suitably used as indices of other gaseous harmful components of the same class. The type of adsorbent used, acid gas,
The amount of alkaline gas to be removed depends on the type of clean room and the type and concentration of the harmful component in the gas depending on the application, so the type of exposure equipment, the installation location and shape of the device, the type and concentration of the harmful component in the gas Preliminary tests can be performed as appropriate according to the required performance, economical efficiency, and the like.

Next, the ion exchange fiber will be described. The ion exchange fiber is composed of a cation exchanger or an anion exchanger, or a cation exchange group and an anion exchanger on a support surface such as a natural fiber or a synthetic fiber or a mixture thereof. An ion exchanger having both exchange groups is supported, and as a method, it may be directly supported on a fibrous support, a woven fabric,
After forming into a knitted or flocked form, it can be supported thereon. In any case, it suffices if the fibers finally support the ion exchanger. As a method for producing the ion-exchange fiber used in the present invention, an ion-exchange fiber produced by utilizing graft polymerization, particularly radiation graft polymerization, is suitable. This is because various materials and shapes can be used. Well, wool, silk, etc. can be applied as the natural fibers, and synthetic fibers made of a hydrocarbon polymer, those made of a fluorinated polymer, or polyvinyl alcohol, polyamide, polyester, poly Acrylonitrile, cellulose, cellulose acetate and the like can be applied.

Examples of the hydrocarbon polymer include aliphatic polymers such as polyethylene, polypropylene, polybutylene and polybutene; aromatic polymers such as polystyrene and poly-α-methylstyrene; and alicyclic polymers such as polyvinylcyclohexane. A polymer or a copolymer thereof is used. Examples of the fluorinated polymer include polytetrafluoroethylene, polyvinylidene fluoride, ethylene-tetrafluoroethylene copolymer, ethylene tetrafluoride-hexafluoropropylene copolymer, and vinylidene fluoride-hexafluoride. A propylene copolymer is used. In any case, the support has a large contact area with the gas flow, a small resistance, a shape that can be easily grafted, a large mechanical strength,
It is sufficient that the material has a small effect of falling off of fiber waste, generation and heat, and can be appropriately selected in consideration of the use application, economy, effect, etc. Usually, polyethylene is generally used and polyethylene or polyethylene and polypropylene and Complexes are particularly preferred.

Next, the cation exchanger is not particularly limited, and various cation exchangers or anion exchangers can be used. For example, in the case of cation exchange, for example, carboxyl groups, sulfonic acid groups, phosphoric acid groups, cation exchange group-containing substances such as phenolic hydroxyl groups, primary to tertiary amino groups, quaternary ammonium groups and the like And an ion exchanger having both the positive and negative ion exchange groups. In particular,
For example, acrylic acid, methacrylic acid, vinylbenzenesulfonic acid, styrene, halomethylstyrene,
Acyloxystyrene, hydroxystyrene, styrene compounds such as aminostyrene, vinylpyridine, 2-methyl-5-vinylpyridine, 2-methyl-5-vinylimidazole, after graft polymerization of acrylonitrile,
If necessary, a fibrous anion exchanger having a cation or anion exchange group can be obtained by reacting sulfuric acid, chlorosulfonic acid, sulfonic acid, or the like.

These monomers are graft-polymerized onto fibers in the presence of a monomer having two or more double bonds, such as divinylbenzene, trivinylbenzene, butadiene, ethylene glycol, divinyl ether, ethylene glycol dimethacrylate. May be. In this way, ion exchange fibers are manufactured. The diameter of the ion exchange fiber is 1 to 1000 μm, preferably 5 to 200 μm.
m, which can be appropriately determined depending on the type of fiber, application, and the like. The use of cation exchange groups and anion exchange groups among these ion exchange fibers can be determined depending on the type and concentration of the component to be removed in the target processing gas. For example, the component to be removed may be measured and evaluated in advance, and the type and amount of the ion exchange fiber corresponding to the measurement and evaluation may be used. Those having a cation exchange group (cation exchanger) when removing alkaline gas, those having anion exchange group (anion exchanger) when removing acidic gas, and those having a mixed gas of both. Fibers having both positive and negative exchange groups can be used.

As a method of flowing gas into the ion exchange fiber,
It is effective to flow perpendicular to the filter-like ion exchange fibers. The flow rate of the gas flowing into the ion-exchange fiber can be determined as appropriate by conducting a preliminary test. However, since the fiber has a high removal rate, the SV is usually 1000 to 100,000 (h).
^-1 ) can be used. As the ion-exchange fiber, as proposed by the present inventors, the use of one produced by radiation graft polymerization is particularly preferred because of its high effect.
It can be appropriately used (Japanese Patent Publication No. 5-9123, Japanese Patent Publication No. 5-67325, Japanese Patent Publication No. 5-43422, Japanese Patent Publication No. 6-24626). The ion-exchange fiber is effective for collecting ionic substances (components), and the acidic gas and alkaline gas targeted by the present invention are considered to be ionic substances. Can be removed.

In particular, the ion exchange filter (fiber) produced by radiation graft polymerization has a wide ion exchanger (anion and / or cation exchanger) because the irradiation of the support is uniformly performed to the inner part. Since it is firmly (strongly) added to the area (added at high density), the exchange capacity is large, and there is an effect that low-concentration ionic substances can be efficiently removed at a high speed, and it is practically effective. is there. In addition, the production by radiation graft polymerization has advantages such as being able to be formed into a shape close to the product, being able to be performed at room temperature, being able to be performed in a gas phase, being able to increase the graft ratio, and being able to produce an adsorption filter with less impurities. For this reason,
It has the following features. The ion exchange fiber (part of the adsorption function) is uniformly added to the ion-exchange fiber produced by the graft polymerization by irradiation with radiation (the addition density is high), so the adsorption speed is high,
And the amount of adsorption is large. Low pressure loss.

When the coexistence of a very small amount of fine particles (particulate matter) is a problem (when the substrate is of high quality and high precision and a very small amount of fine particles is a problem), the removal of the fine particles is
The removal can be performed in addition to the removal of the gaseous harmful components.
For the removal of the fine particles, a filter method or a method using photoelectrons already proposed by the present inventors can be appropriately used depending on required performance and the like. As the filter system, a dust filter using a well-known filter system, for example, a medium-performance filter, a HEPA filter, an ULPA filter, or the like can be appropriately used in combination. In addition, for the charging and collection (removal) of the fine particles by the photoelectrons, the method already proposed by the present inventors can be appropriately used (Japanese Patent Application Publication No.
No. 5859, No. 6-34941, No. 6-74
No. 910, Japanese Patent Publication No. Hei 8-211, Patent No. 26232
No. 90, each publication). The method using photoelectrons is preferable because fine particles can be removed by installing a photoelectron emitting material and an electrode in a portion of the exposure apparatus where ultraviolet light is emitted (since fine particles can be removed with a simple configuration).

[0025]

Next, examples of the present invention will be described. However, the present invention is not limited to the following examples. Example 1 FIG. 1 shows an exposure apparatus 1 using a laser light source provided with a photocatalyst and an ion exchange fiber of the present invention, wherein (a) is a cross-sectional view of the exposure apparatus viewed from the side, and (b) is a top view. FIG. Excimer light (UV light) emitted from a light source 2 using an excimer laser is shaped into a required beam shape and size by a beam shaping system, and then passes through an illumination system unit 3 such as various relay lenses and mirrors. The light is incident on a mask 4 on which a predetermined pattern is formed, and the mask pattern is imaged on a wafer 7 placed on an XY stage 6 via a projection optical system (refraction system, reflection system, catadioptric system) unit 5. I do. Exposure device 1
The temperature and humidity of the air in the chamber 8 which is the heart of the air conditioner are kept constant by a temperature / humidity controller by an air conditioner 9 and a blower fan (not shown).

Here, the gaseous harmful components and the fine particles in the clean room air 10 introduced into the exposure apparatus 1 are first converted into ionic substances (NOx, SOx, NH ₃ , Amine),
Fine particles are removed. The part consisting of 11 and 12 is
An outside air intake, which naturally takes in outside air (clean room air) according to the pressure difference between the inside and outside of the chamber. In the exposure apparatus 1, photocatalysts 13 to 15 are installed in a passage portion of air to be irradiated with UV light (a portion around an arrow indicating the UV light emitted from the light source 2). H. C is removed. The photocatalyst is described in H.E.
Gaseous harmful components such as NH ₃ and amine coexisting with C are also detoxified. That is, even if there is harmful generated gas in the air or the air removed by the ion-exchange fiber or in the exposure apparatus, it is treated, which is a feature of the present invention. The photocatalyst according to the present embodiment includes a honeycomb-shaped photocatalyst 13 and an illumination system
Are provided with a honeycomb-shaped photocatalyst 14 and a plate-shaped photocatalyst 15.

Reference numeral 16 denotes a HEPA filter, which is installed to remove dust generated in the exposure apparatus 1.
That is, a HEPA filter for removing dust is installed at the outlet of the blower fan in the air conditioner 7. However, the filter removes dust in the exposure apparatus 1 when it cannot be completely collected or in an emergency. I do. NOx and S as gaseous harmful components are contained in clean room air 10 of class 1,000.
Ox is 80~100ppb, the NH ₃ 95~100pp
b, non-methane H. C (organic gas) is 1.0-1.2p
pm, and a chemically amplified photosensitive agent is applied to the wafer 7, and NH ₃ or H.P. C is generated, but due to the configuration of the present invention, the inside of the exposure apparatus 1
NOx, SOx, NH _3: 1ppb below, H. C: 0.
1 ppm or less is obtained. Arrows 17 _{-1 to} 17 _{-4 in} FIG.
Indicates the direction of air flow.

Embodiment 2 FIG. 2 is a view in which ion exchange fibers _11-1 are added to the inlet of the chamber section 8 in FIG. 1 of Embodiment 1 to further enhance the collection and removal of ionic gas. It is. 2 that are the same as those in FIG. 1 have the same meaning.

Example 3 Class 1,000 clean room air was introduced into the exposure apparatus shown in FIG. 1 (one in which the outside air inlets 11 and 12 were removed and closed), and the air cleanliness in the chamber was measured. Examined. The air cleanliness is determined by (1) measurement of a contact angle on a wafer placed on an XY stage in a chamber, (2) H.O. in air in a chamber. Measurement of C concentration, NH ₃ concentration and particle concentration, (3) quartz glass was installed in the chamber,
Deposits on the glass were measured and examined. 1) Exposure equipment Light source: excimer laser

2) Clean room air (1) Fine particles: Class 1,000 (2) Non-methane H. C concentration: 1.2 ppm (3) NH ₃ concentration: 95 ppb 3) Photocatalyst As shown in FIG. 1, a honeycomb-shaped photocatalyst was installed in the illumination system and the chamber. Photocatalyst adjustment method: Liquid Ti on honeycomb ceramic
One coated with O ₂ and heat-treated at 80 ° C. 4) Dust filter (16 in FIG. 1) HEPA filter 5) Measurement (1) Contact angle: Water drop contact angle meter (2) Non-methane H. C: GC method (3) NH ₃ : chemiluminescence method (4) Fine particle concentration: particle counter

Results 1) Contact Angle The relationship between the elapsed time and the contact angle is shown in FIG. In Fig. 3 -〇-
Are the samples of the present invention, and-●-and-△-are, for comparison, those exposed to the clean room air (sample air introduced into the exposure apparatus) and the air after removing the photocatalyst, respectively. 2) In the air in the chamber. C concentration, NH ₃ concentration, and fine particle concentration Table 1 shows the respective concentrations in the air after 24 hours, 71 hours, and 1 week after the operation of the apparatus. Table 1 shows, as a comparison, the results obtained in the same manner without the photocatalyst and without the dust filter (HEPA filter).

[0032]

[Table 1]

3) Deposits on glass installed in the chamber section Clean room air is introduced into the apparatus once a day (replacement of air in the apparatus is performed), and the apparatus is operated for a long time to deposit on the glass. Was examined. (1) Visual observation In the apparatus without the photocatalyst installed, fogging was observed on the glass surface after 20 days, but in the apparatus of the present invention, no fogging was observed even after 6 months of continuous operation. (2) When the cloudy component was measured by ESCA analysis and SEM, SiOx was detected. It was presumed that the cause of SiOx was caused by siloxane (HC) which is a gas generating component in a clean room.

The exposure apparatus of Embodiment 4 Embodiment 3 (FIG. 1), in front of the dust removal filter (HEPA filter) 16 as the code 11 _-1 2,
The following ion-exchange fibers were added, and a sample gas (clean room air) was introduced into the exposure apparatus in the same manner as in Example 3.
The removal performance of ₃ was examined. The test conditions and the conditions of the measuring device are the same as in the third embodiment. Ion exchange fiber: Cationic type Production method: Electron beam 2 in fibrous polypropylene in nitrogen
Irradiated with 0 Mrad and then immersed in glycidyl methacrylate to perform a graft polymerization reaction. After the reaction, sulfonation was performed with an aqueous solution of sodium sulfite. Results The relationship between the elapsed time and the NH ₃ concentration in the chamber is shown in FIG. In FIG. 4, -〇- indicates that of this example,-△-indicates that of a photocatalyst only (without ion exchange fiber) as a comparison, and ↓ indicates the measurement limit (<1 ppb). From FIG.
It can be seen that the addition of ion exchange fibers accelerates the NH ₃ removal rate.

[0035]

According to the present invention, the following effects can be obtained. 1) In the exposure apparatus, at least one of the ultraviolet light irradiation portions
By providing a photocatalyst in part, (1) the photocatalyst exhibits photocatalytic activity by ultraviolet light, the space in the hydrocarbon and NH ₃ in the exposure apparatus decomposing. (2) From (1), a decrease in illuminance due to clouding of an optical material such as a lens was prevented. (3) Effective treatment of harmful gases was achieved with a simple structure in which only a photocatalyst was installed.

2) By adding an ionic substance removing material to the photocatalyst of the above 1), (1) an effect of removing an ionic substance such as NH ₃ (speed)
Was accelerated. (2) The different types of harmful gases of ionic substances and hydrocarbons were removed. (3) Since the ionic substance is collected by the ionic substance removing material, the life of the photocatalyst is prolonged. 3) From the above 1) and 2), the harmful gas was effectively removed. (1) The surface insolubilization phenomenon of the chemically amplified resist was reduced,
Higher resolution exposure has become feasible. (2) Since the harmful gas can be effectively treated with a simple structure, the practicability is improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an example of an exposure apparatus of the present invention.
(A) is front sectional drawing, (b) is a top view.

FIG. 2 is a configuration diagram showing another example of the exposure apparatus of the present invention;
(A) is front sectional drawing, (b) is a top view.

FIG. 3 is a graph showing a change in a contact angle (degree) according to an elapsed time (h).

FIG. 4 is a graph showing a change in NH ₃ concentration (ppb) with elapsed time (h).

[Explanation of symbols]

1: exposure apparatus, 2: light source, 3: illumination system part, 4: mask,
5: Projection optical system unit, 6: XY stage, 7: wafer,
8: chamber part, 9: air conditioner, 10: outside air, 11: ion exchange fiber, 12: HEPA filter, 13 to 15:
Photocatalyst, 16: HEPA filter, 17: Air flow

Claims (2)

[Claims] 1. An exposure apparatus having an air conditioner and a light source for emitting ultraviolet light, wherein a photocatalyst is provided in at least a part of the exposure apparatus which is irradiated with the ultraviolet light. 2. The exposure apparatus according to claim 1, wherein an ionic substance removing material is provided in an air flow path in the exposure apparatus.