JP2001028331A - Optical device, aligner using the same, gas flow-in method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce contamination of an optical member, such as a lens with a flow-in gas, related to an optical device, an alignes using it, and gas flow-in method. SOLUTION: When a gas supplied from a gas supply device 16 at a prescribed flow speed flows into a casing 15, the flow speed of the gas is decreased to lower than a prescribed speed, so that when reaching the surface of an optical member L2, the flow speed of the gas is lower and easy to disperse, with contained impurities becoming difficult to adhere to the optical member.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical device in which an optical member is housed in a casing such as a lens barrel into which nitrogen gas or the like flows, an exposure apparatus using the optical device, and a gas inflow method.

[0002]

2. Description of the Related Art In a conventional exposure apparatus, when oxygen exists in a space through which exposure light passes in an illumination optical system or a projection optical system, if exposure light using a light source such as an ArF excimer laser is used, an emission spectrum line is obtained. Overlaps with the oxygen absorption spectrum line region, so that a phenomenon occurs in which oxygen absorbs exposure light and becomes ozonized.

[0003] As a result, a fogging substance may precipitate on the surface of the optical lens, which may adversely affect the lens characteristics.
Therefore, in a conventional exposure apparatus, a part or all of a space around an optical path from a light source to a substrate to be processed is covered with a cover, and the inside of the cover is filled with a gas inert to exposure light, for example, a nitrogen gas. ing.

As a means for replacing the optical path with nitrogen gas,
For example, there is a structure as shown in FIG. That is, in a structure in which the lenses 101 to 103 are sandwiched by the spacing rings 104 and 105 and wrapped by the lens barrel 106, nitrogen gas is introduced from the pipe joint 107 as nitrogen gas inflow means,
The lens 10 passes through the inflow side flow path 106 a in the lens barrel 106, passes through a hole 104 a formed in the spacing ring 104, and
1, 102 and the lenses 102, 103. The space between the lenses 101 and 102 and the space between the lenses 102 and 103 communicate with each other. The nitrogen gas flowing between the lenses is discharged from the piping joint 108 through a discharge-side flow path 106b having a similar structure.

[0005]

However, in the above-mentioned conventional gas inflow means, the inflow side flow passage 106a of the lens barrel 106 and the hole 104a of the spacing ring 104 coincide with each other. The nitrogen gas entering
One place 10 of the lens 102 on the extension of the hole 104a
2a will be intensively hit. Even if the nitrogen gas is sufficiently clean, the purity is 99.999%, and it contains dirt in the piping (degassing of impurities generated by the piping itself). Contamination, and the rate of the contamination was much faster than others.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and has an optical apparatus capable of reducing contamination of an optical member such as a lens by an inflowing gas, an exposure apparatus using the same, and a gas inflow method. The purpose is to provide.

[0007]

The present invention has the following features to attain the object mentioned above. That is, the optical device according to the first aspect of the present invention will be described with reference to FIGS. 1 to 6.
5) An optical device (IU, PU) housed in the casing, wherein when the gas supplied at a predetermined flow rate from the gas supply device (16) flows into the casing, the flow rate of the gas is set to the predetermined flow rate. Gas inflow mechanism (14A, 1
4a, 14b).

[0008] In the gas inflow method according to the tenth aspect, the casing (1) accommodating the optical members (L1 to L3).
5) A gas inflow method in which a gas supplied at a predetermined flow rate from a gas supply device (16) flows into the casing, wherein when the gas flows into the casing, the flow rate of the gas is set to be lower than the predetermined flow rate. Decreasing technology is employed.

In the optical device and the gas inflow method, when the gas supplied from the gas supply device (16) at a predetermined flow rate is caused to flow into the casing (15), the gas flow rate is made lower than the predetermined flow rate. , Optical member (L2)
At the time when the gas reaches the surface, the flow velocity of the gas is reduced, and the gas is easily dispersed, so that impurities contained therein hardly adhere to the optical member.

According to a fourth aspect of the present invention, in the optical member (IU, PU) for housing the optical members (L1 to L3) in the casing (15), when the gas flows into the casing, A gas inflow mechanism (14A, 1A) for dispersing and inflowing the gas from a plurality of locations around the optical member.
4a, 14b).

In the gas inflow method according to the eleventh aspect, the casing (1) accommodating the optical members (L1 to L3).
5) A gas inflow method in which a gas flows into the inside, wherein a technique is adopted in which the gas flows from a plurality of locations around the optical member.

In the optical device and the gas inflow method, the gas is dispersed and allowed to flow from a plurality of locations around the optical member (L2). Can be reduced as compared with the case where is made to flow in a concentrated manner, and the contained impurities are less likely to adhere to the optical member.

According to a ninth aspect of the present invention, there is provided an exposure apparatus for guiding exposure energy (IL) to a mask (R) to form a pattern on the mask on a surface of a substrate (W).
The optical device (IU, P) according to claim 1.
U), and an optical system (4) for guiding the exposure energy to the mask or an optical system (P for guiding the pattern to the substrate via the optical members (L1 to L3) in the optical device.
L).

In this exposure apparatus, the exposure energy (I) is controlled by the optical members (L1 to L3) in the optical apparatus.
Since at least one of the optical system (4) for guiding L) to the mask (R) or the optical system (PL) for guiding the pattern to the substrate (W) is configured, the adhesion of impurities to the optical member is reduced, and the lens life is shortened. Can be improved, and good exposure characteristics can be maintained.

13. An optical device according to claim 12, wherein the optical member is housed in a casing, and when the gas supplied from the gas supply device flows into the casing, the gas supply device and the casing are provided. And a filter for removing impurities generated between the gas from the gas. According to this optical device, the gas that has passed through the filter can be supplied into the casing,
Adhesion of impurities to the optical member is reduced.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of an optical apparatus, an exposure apparatus using the same, and a gas inflow method according to the present invention will be described with reference to FIGS.

FIG. 1 is a view schematically showing the entire configuration of an exposure apparatus according to the present embodiment. The exposure light source 1 used is a deep ultraviolet light (wavelength 19 nm) by an ArF excimer laser.
(3.4 nm) of exposure light (exposure energy) IL.

Exposure light IL emitted from exposure light source 1
Is transmitted through the window 2a and passes through the illumination system unit (optical device) I.
The light enters the mirror 3a in U. The exposure light IL reflected by the mirror 3a is reflected by the mirror 3b and enters the illumination optical system 4. A beam matching unit including a movable mirror for adjusting the position of an optical path (optical axis) between the exposure light source 1 and the illumination optical system 4 is provided between the exposure light source 1 and the illumination optical system 4.

The illumination optical system 4 includes a relay lens, an optical integrator (such as a fly-eye lens or a rod lens) for equalizing the exposure light IL, and an exposure light I.
It has a plurality of lens elements such as an input lens for making L incident on the optical integrator, a relay lens for condensing the exposure light IL emitted from the optical integrator on a reticle (mask) R, and a condenser lens.

Exposure light IL emitted from illumination optical system 4
Is reflected by the mirror 3c, passes through the window 2b, and enters the reticle R on the reticle stage RST that can move two-dimensionally. Further, the exposure light IL transmitted through the reticle R
Is a projection system unit (optical device) PU through the window 2c.
Is incident on the projection optical system PL, passes through a plurality of lens elements constituting the projection optical system PL, and is incident on the wafer (substrate) W.
Form on the surface. Each of the windows 2a, 2b, 2c is a glass plate or the like made of quartz or fluorite that transmits far ultraviolet rays.

The wafer W is placed in a three-dimensional direction (XYZ directions).
The wafer stage WST is mounted on a movable wafer stage WST, and the position of the wafer stage WST in the XY plane is measured by the laser interferometer 5 (only one is shown in FIG. Provided for each of the X and Y axes).
Wafer stage WST is stepped and moved based on the measurement value of laser interferometer 5, so-called stepping movement.
The stepping movement and the exposure are repeated by the AND repeat method, and the pattern is sequentially exposed on the wafer W.

Above wafer stage WST, a light projecting system 6a and a light receiving system 6b of a focus detecting system for optically detecting the height position of wafer W are provided. The measurement light is obliquely incident on the wafer W, and the measurement light reflected on the surface of the wafer W is received by the light receiving system 6b and output to the control device C. Then, the controller C detects the height position of the wafer W based on the received light receiving signal, and moves the wafer stage WST in the height direction to adjust the focus of the projection optical system PL.

The illumination system unit IU and the projection system unit PU are, as shown in FIG.
13, the exposure light I from the exposure light source 1 to the window 2b
It has a structure that seals the optical path of L and the optical path of the exposure light IL from the window 2c to the lens immediately above the wafer W. Note that the reticle R and the reticle stage RST are also sealed by the sealing member 7. That is, the hatched portion in FIG. 1 is isolated from the outside air. Note that at least a part of the optical path of the wafer W, the wafer stage WST, and the interferometer 5 may be sealed with a sealing member to be isolated from the outside air.

As shown in FIGS. 2 and 3, the illumination system unit IU and the projection system unit PU are arranged on the optical path of the exposure light IL and are part of a plurality of lens elements in the illumination optical system 4 or the projection optical system PL. The lens L constituting
1 to L3, and spacing rings (collision members, annular members, spacing ring members) 14A, 14B, 14 which are arranged between the lenses L1 to L3 so as to surround them and regulate the spacing between the lenses.
C, a lens barrel (casing) 15 for housing and holding them, and a gas supply device 16 provided outside and supplying nitrogen gas between the lenses L1 to L3. The gas supply device 16 includes a cylinder in which high-purity nitrogen gas having a purity of, for example, 99.999% is sealed.

The lens barrel 15 is formed with an introduction hole 15a for allowing nitrogen gas to flow between the lenses and a discharge hole 15b for discharging nitrogen gas inside to the outside in a radial direction of the lens barrel 15. ing. An inlet joint 17 for piping connected to a gas supply device 16 is provided at an outer opening of the introduction hole 15a, and an outlet joint 18 for piping is provided at an outer opening of the discharge hole 15b. I have.

The spacing rings 14A and 14B are provided with an inlet 1 which is an inner opening of the inlet 15a and the outlet 15b.
5c and a discharge groove 14a formed in the surface facing the discharge port 15d along the circumferential direction, and a plurality of grooves (six in this embodiment, which are arranged at equal intervals in the circumferential direction in the flow groove 14a). ) Are formed respectively. These through holes 14b are arranged at positions shifted from the inlet 15c. The inner peripheral surface of the lens barrel 15 is provided on the inner peripheral surface of the spacing ring 14A with the spacing ring 14a.
A communication groove 15e extending in the axial direction to the flow groove 14a of B and connecting them is formed. The space between the lens L1 and the lens L2 and the communication groove 15 are provided in the spacing ring 14A.
An opening 15f for communicating with e is formed.

Next, a method of flowing nitrogen gas into the illumination system unit IU and the projection system unit PU will be described. First, nitrogen gas is introduced into the lens barrel 15 from the inflow joint 17 through the introduction hole 15a. The nitrogen gas is supplied to the spacing ring 1 facing the introduction port 15c of the introduction hole 15a.
4A, it flows in the circumferential direction using the flow groove 14a as a flow path. Since the flow groove 14a of the spacing ring 14A is provided on the inner extension line of the introduction hole 15a, the nitrogen gas once hits the flow groove 14a, and flows in two directions (circumferential direction).
And the flow velocity decreases.

The nitrogen gas flowing in the flow grooves 14a flows between the lenses L1 and L2 from the plurality of through holes 14b. At this time, the nitrogen gas is supplied to the plurality of through holes 14.
b, the flow velocity in each through-hole 14b further decreases. Therefore, when the nitrogen gas supplied at a predetermined flow rate flows into the lens barrel 15, the flow groove 14 a and the plurality of through-holes 14 b of the spacing ring 14 </ b> A reduce the flow rate of the nitrogen gas below the predetermined flow rate. Functions as a mechanism.

The nitrogen gas flowing between the lens L1 and the lens L2 is introduced into the flow groove 14a of the distance ring 14B via the opening 15f and the communication groove 15e of the distance ring 14A, and is introduced into the flow groove 14a of the distance ring 14A. Is also introduced into the flow groove 14a of the spacing ring 14B via the communication groove 15e, and flows in the circumferential direction along the flow groove 14a of the spacing ring 14B. Further, the nitrogen gas is supplied to the lens L2 and the lens L2 from a plurality of through holes 14b provided in the spacing ring 14B.
It flows between 3. The nitrogen gas that has flowed between the lens L2 and the lens L3 is discharged again through the through-hole 14b or the spacing ring 14B, the discharge opening 1
It is discharged from the discharge joint 18 to the outside (a recovery device or the like) through the discharge joint 4a and the discharge hole 15b.

Therefore, in this embodiment, the flow rate of the nitrogen gas supplied from the gas supply device 16 at a predetermined flow rate is controlled by the flow grooves 14a and the plurality of through holes 14b.
Since the nitrogen gas flows into the lens barrel 15 at a speed lower than the predetermined flow speed, the nitrogen gas flow speed is reduced at the time when the nitrogen gas reaches the surface of the lens L2, and the nitrogen gas is easily dispersed. It becomes difficult to adhere.

Further, since nitrogen gas is dispersed and allowed to flow from a plurality of locations around the lens L2, the location corresponding to the surface of the lens L2 is not concentrated at one location, and the nitrogen gas is concentrated at one location. As a result, the overall flow rate can be reduced, and the contained impurities are less likely to adhere to the lens L2.

As described above, since the attachment of impurities to the lens surface due to the nitrogen gas is reduced, the cleaning effect by irradiating the lens surface with the exposure light IL exceeds the adhesion amount, and the cleaning is performed by repeated use. Repeatedly, it is possible to always keep the lens surface in a good state.

[Second Embodiment] Next, a second embodiment of the present invention will be described with reference to FIG. In the first embodiment, the flow grooves 1 are formed in the spacing ring 14A in order to decelerate the nitrogen gas.
4a and a plurality of through holes 14b. On the other hand, in the second embodiment, as shown in FIG.
A first plate member (collision member) 25 for reducing the flow rate of the nitrogen gas flowing from the through-hole 24 a from the flow rate when the nitrogen gas is supplied from the gas supply device 16 is provided inside the inside.

That is, in the second embodiment, the first plate member 25 is moved to a position where the nitrogen gas flowing from the through-hole 24a of the spacing ring 24 corresponding to the introduction port 15c formed in the lens barrel 15 directly hits. The nitrogen gas flowing from the through-hole 24a once strikes the first plate member 25 and is decelerated, since the nitrogen gas flows in the lens L2 side.
Therefore, impurities contained in the gas hardly adhere to the lens L2.

The nitrogen gas striking the first plate member 25 is deflected from the lens L2 side and guided toward the lens L1. The nitrogen gas flows inside the spacing ring 24 in the direction of the lens L1. A second plate member 26 that warps from the side may be provided.

That is, the second plate member 26 is arranged so as to change the flow direction of the nitrogen gas from the lens L1 side to an intermediate portion between the lens L1 and the lens L2, thereby preventing the nitrogen gas from being guided to the lens L1. Therefore, the surface of the lens L1 does not fog.

Third Embodiment Next, an optical apparatus according to the present invention, an exposure apparatus using the same, and a third embodiment of a gas inflow method will be described.
An embodiment will be described with reference to FIG.

The difference between the third embodiment and the first embodiment is that, in the first embodiment, a plurality of through holes 14b of the spacer ring 14A are formed in the circumferential direction and nitrogen gas flows thereinto. In the third embodiment, as shown in FIG. 6, a first through hole 34a and a second through hole 34b are formed in a spacing ring (collision member) 34 in the optical axis direction of the lens to disperse nitrogen gas. It is a point that is flowing.

That is, in the third embodiment, the spacing ring 3
4, it is not always necessary to form a circumferential flow groove,
The structure is such that a flow groove 34c may be formed in a part of the spacing ring 34. That is, the flow groove 34c is formed on the outer surface of the spacing ring 34 so as to communicate the inlet 15c formed in the lens barrel 15 with the first through hole 34a and the second through hole 34b.

In this embodiment, the inlet 15c and the first,
Since the positions of the second through holes 34a and 34b are shifted from each other, the nitrogen gas supplied to the preliminary space between the outer peripheral surface of the spacing ring 34 and the inner peripheral surface of the lens barrel 15 temporarily
And the flow velocity decreases. Then, the nitrogen gas flows from the flow groove 34c to the first,
It is supplied into the lens barrel 15 through the second through holes 34a and 34b.

Therefore, the nitrogen gas flows through the flow grooves 34c.
And the first and second through holes 34a, 34
b, the surface of the lens L2 is not fogged.

It should be noted that even if the number of through holes is plural,
There may be one, but if there is more than one, as described above, the nitrogen gas can be dispersed and flowed in, and the fogging of the lens can be further reduced as compared with the case of one.

As a modification of the first embodiment shown in FIG. 3, a nitrogen gas from a gas supply device 16 is supplied to the lens barrel 15.
When the gas is introduced into the gas supply device 16,
Fig. 4
As shown in FIG. 7, a filter 19 for flowing the inflowing nitrogen gas and adsorbing impurities in the nitrogen gas is connected to the inlet 15c.
To be provided. By providing the filter 19 at the inlet 15c in this manner, the flow rate of the nitrogen gas can be further reduced. In each of the embodiments shown in FIGS. 5 and 6, the nitrogen gas from the gas supply device 16 is directly introduced into the lens barrel 15, but the filter may be provided at the inlet 15c.

In the case of the first embodiment, the filter 19
May be provided in any flow path from the inflow joint 17 to the through hole 14b. For example, you may provide in each through-hole 14b. When the filter 19 is provided, the inlet 15c and the through-hole 14b face each other, and
From 5c, the nitrogen gas may be introduced into the lens barrel without being applied to the spacing ring. That is, the filter 19 plays a role of reducing the flow rate of the nitrogen gas. Further, in the case of the second and third embodiments, the filters 19 may be provided in the through holes 24a and the first and second through holes 34a and 34b, respectively.

Although a plurality of through holes 14b of the spacing ring 14A are formed in the circumferential direction, a plurality of through holes 14b may be formed in the axial direction if the spacing ring has a sufficient width. Also in this case, the nitrogen gas is dispersed by the plurality of through holes, and the nitrogen gas can flow between the lenses at a low flow rate.

When the distance between the lenses can be made large, the nitrogen gas flowing from the through-holes 14b is prevented from hitting the lens surface as much as possible. It is preferable to form the through holes 14b so as not to position the surface.

In the first embodiment, a flow groove 14a and a plurality of through holes 14b are formed in the spacing ring 14A, and gas is supplied from one gas inlet to the lens through the flow groove 14a and the through hole 14b. But the lens barrel 1
A plurality of gas inlets may be formed in 5, and gas may be supplied between the lenses from the gas inlets through the above-described flow grooves 14a and through holes 14b.

Further, a ring-shaped pipe may be disposed in the lens barrel 15 instead of the flow groove 14a. That is, a pipe connected to the gas supply device may be connected to the outer circumference of the ring-shaped pipe, and a plurality of gas inlets may be formed on the inner circumference of the ring-shaped pipe. At this time, the gas inlets formed on the inner peripheral side and the openings of the pipes connected on the outer peripheral side are formed so as to be shifted from each other so as not to face each other. The first
If the spacing ring 14A of the embodiment is used, the above piping and the like become unnecessary.

In the first embodiment, the configuration in which the space between the lens L1 and the lens L2 and the space between the lens L2 and the lens L3 are connected by the communication groove 15e has been described. Alternatively, the nitrogen gas may be introduced into the space between the lens L2 and the lens L3 independently.
In that case, the lens barrel 15 constituting a part of each space
Then, an inlet hole 15a and a discharge hole 15b are formed, an inlet joint 17 is provided in the inlet hole 15a, and a discharge joint 18 is provided in the discharge hole 15b.

In the embodiment, a filter is used to reduce the flow rate of the nitrogen gas. The filter may be a HEPA filter (High Efficiency Particulate Air-filter) for removing impurities such as dust and moisture, or an ULPA filter. (Ultra LowPenetration Air-filte
r) and / or a chemical filter for removing chemical substances.

For example, chemical filters include ammonia, amine compounds, sulfur compounds, siloxane,
Activated carbon filter (for example, silicon-based organic matter such as silazane, silanol, etc.), impurities such as plasticizer (phthalic acid ester) and flame retardant (phosphoric acid, chlorine-based substance)
"Gigasoap" manufactured by Nitta Corporation) or a zeolite filter can be used.

As described above, the chemical filter, the HEP
By supplying gas into the casing through at least one of the A filter and the ULPA filter, contamination of an optical member in the casing, such as a lens surface or a mirror surface, can be reduced.

For example, in an exposure apparatus,
When using exposure light in the following wavelength range, if impurities (for example, water molecules, hydrocarbon molecules, or other substances that absorb the exposure light) generated from the pipe itself enter the casing, May adhere to the surface of the optical member inside, and the transmittance or reflectance of the optical system may fluctuate. Further, the exposure light is absorbed by water molecules or a substance that absorbs the exposure light, the intensity of the exposure light on the wafer surface changes, and the exposure amount on the wafer surface may change. However, as described above, if the light is once passed through the filter before the gas is blown onto the optical member, it is possible to suppress the change in the transmittance and the reflectance of the optical system and the change in the intensity of the exposure light.

In each of the above embodiments, a nitrogen gas is used as a gas to be supplied. However, an inert gas such as helium, neon, argon, krypton, xenon, and radon may be used. When the wavelength of the exposure light is KrF, chemically clean dry air (air from which a substance causing clouding of a lens, for example, ammonia ions floating in a clean room has been removed, or air having a humidity of 5% or less) )
May be used.

Furthermore, in each of the above embodiments, the generation of impurity gas such as a stainless steel pipe or a Teflon (registered trademark) tube is suppressed (less) as a pipe disposed between the gas supply device 16 and the inflow joint 17. It is desirable to use the material given. Similarly, it is desirable that the spacing ring and the lens barrel are formed of a stainless steel material or an aluminum material coated with Teflon or the like.

The exposure apparatus of the above embodiment can also be applied to a proximity exposure apparatus that exposes a pattern of a mask by bringing a mask and a substrate into close contact instead of a reticle without using a projection optical system.

The application of the exposure apparatus is not limited to an exposure apparatus for manufacturing a semiconductor. For example, an exposure apparatus for a liquid crystal for exposing a liquid crystal display element pattern to a square glass plate and a thin film magnetic head are manufactured. Can be widely applied to an exposure apparatus for the purpose.

In this embodiment, the light source of the exposure apparatus is g-line (436 nm), i-line (365 nm), KrF
An excimer laser (248 nm), an ArF excimer laser (193 nm), an F ₂ laser (157 nm), or a light source having a shorter wavelength may be used. In the present invention,
The present invention can also be applied to an exposure apparatus using a charged particle beam such as an X-ray or an electron beam. For example, when an electron beam is used, the configuration of an exposure apparatus uses a thermionic emission type lanthanum hexaborite (LaB ₆ ) or tantalum (Ta) as an electron gun. An electron optical system consisting of a vessel is used. The optical path through which the electron beam passes is in a vacuum state.

The magnification of the projection optical system may be not only a reduction system but also any one of a unity magnification and an enlargement system. The projection optical system, when using a far ultraviolet rays such as an excimer laser using a material which transmits far ultraviolet rays such as quartz and fluorite as glass material, a catadioptric or refractive system when using a F ₂ laser or X-ray An optical system (a reticle of a reflection type is also used). When an electron beam is used, an electron optical system including an electron lens and a deflector may be used as the optical system. It goes without saying that the optical path through which the electron beam passes is in a vacuum state.

When a linear motor (see US Pat. No. 5,623,853 or US Pat. No. 5,528,118) is used for the wafer stage or reticle stage, either an air levitation type using an air bearing or a magnetic levitation type using Lorentz force or reactance force is used. You can. The stage may be of a type that moves along a guide or a guideless type that does not have a guide.

The reaction force generated by the movement of the wafer stage may be mechanically released to the floor (ground) by using a frame member as described in US Pat. No. 5,528,118. The reaction force generated by moving the reticle stage is filed in the U.S.
As described in S / N 416558, a frame member may be used to mechanically escape to the floor (ground).

As described above, the exposure apparatus of the present invention is manufactured by assembling various subsystems including the above-described respective components so as to maintain predetermined mechanical accuracy, electrical accuracy, and optical accuracy. You. Before and after this assembly, adjustments to achieve optical accuracy for various optical systems, adjustments to achieve mechanical accuracy for various mechanical systems, and various electrical systems before and after this assembly to ensure these various accuracy Are adjusted to achieve electrical accuracy. The process of assembling the exposure apparatus from various subsystems includes mechanical connections, wiring connections of electric circuits, and piping connections of pneumatic circuits among the various subsystems. It goes without saying that there is an assembling process for each subsystem before the assembling process from these various subsystems to the exposure apparatus. After the assembly process of the various subsystems into the exposure device is completed,
Comprehensive adjustment is performed, and various accuracies of the entire exposure apparatus are secured. It is desirable that the manufacture of the exposure apparatus be performed in a clean room in which the temperature, cleanliness, and the like are controlled.

In the semiconductor device, a step of designing the function and performance of the device, a step of manufacturing a reticle based on the design step, a step of manufacturing a wafer from a silicon material, and a step of forming a reticle pattern by the exposure apparatus of the above-described embodiment. It is manufactured through a step of exposing a wafer, a device assembling step (including a dicing step, a bonding step, and a package step), an inspection step, and the like.

[0064]

According to the present invention, the following effects can be obtained.
According to the optical device according to the first aspect and the gas inflow method according to the tenth aspect, when the gas supplied at a predetermined flow rate from the gas supply device flows into the casing, the flow rate of the gas is made lower than the predetermined flow rate. Therefore, the gas is easily dispersed with the deceleration, the adhesion of the contained impurities to the optical member can be suppressed, the contamination rate can be reduced, and the life of the optical member can be greatly improved.

According to the optical device of the third aspect, the gas inflow mechanism is disposed between the inlet and the surface of the optical member.
Since the collision member is provided for colliding the gas introduced from the inlet, the gas once hits the collision member and is decelerated, so that the impurities contained therein can be suppressed from adhering to the optical member.

The optical device according to the fourth aspect and the first aspect.
According to the gas inflow method described in 1, the gas is dispersed and introduced from a plurality of locations around the optical member, so that the overall flow velocity is reduced as compared with a case where the gas is concentrated and introduced from one location, Adhesion of the contained impurities to the optical member can be suppressed, and the contamination rate can be reduced to greatly improve the life of the optical member.

According to the optical device of the fifth aspect, a flow groove formed in the annular member along a circumferential direction on a surface facing the gas inlet formed in the casing; Is formed with a plurality of through-holes spaced apart from each other, so that the gas can flow from the plurality of through-holes through the circulation groove, and the gas is decelerated and dispersed in a simple configuration. be able to.

According to the optical device of the sixth aspect, since the through-hole is disposed at a position shifted from the inlet, the gas introduced from the inlet does not directly enter the through-hole, but flows once. It can be dispersed and decelerated by hitting the groove.

According to the optical device of the present invention, since the annular member is a spacing ring member arranged between adjacent optical members to regulate the spacing between these optical members, only the processing of the spacing ring member is required. , And can be realized at low cost without increasing the number of members.

According to the optical device of the present invention, since the gas inflow mechanism has the filter for circulating the inflowing gas and adsorbing the impurities in the gas, it removes the impurities in the piping mixed with the gas. And the purity of the optical member can be increased.

According to the ninth aspect of the present invention, at least one of the optical system for guiding the exposure energy to the mask or the optical system for guiding the pattern to the substrate is constituted by the optical member in the optical device. The adhesion of impurities can be reduced, the life of the lens can be improved, the maintenance cost can be reduced, and a decrease in exposure energy such as exposure light can be prevented, so that exposure can be performed efficiently.

According to the optical device of the twelfth aspect, the gas that has passed through the filter can be supplied into the casing, and the adhesion of impurities to the optical member is reduced.

[Brief description of the drawings]

FIG. 1 is a schematic overall configuration diagram showing an exposure apparatus according to a first embodiment of an optical apparatus, an exposure apparatus using the same, and a gas inflow method according to the present invention.

FIG. 2 is a cross-sectional view showing a part of an illumination system unit and a projection system unit in a first embodiment of an optical apparatus, an exposure apparatus using the same, and a gas inflow method according to the present invention.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is an enlarged cross-sectional view showing a main part of a lens barrel and a spacing ring in another example of the first embodiment of the optical apparatus, the exposure apparatus using the same, and the gas inflow method according to the present invention.

FIG. 5 is a cross-sectional view of a main part showing a part of an illumination system unit and a projection system unit in a second embodiment of an optical apparatus, an exposure apparatus using the same, and a gas inflow method according to the present invention.

FIG. 6 is a sectional view of a main part showing a part of an illumination system unit and a projection system unit according to a third embodiment of the optical apparatus, the exposure apparatus using the same, and the gas inflow method according to the present invention.

FIG. 7 is a sectional view of a main part showing a part of an illumination system unit and a projection system unit in a conventional example of an optical apparatus according to the present invention, an exposure apparatus using the same, and a gas inflow method.

[Explanation of symbols]

Reference Signs List 1 exposure light source 4 illumination optical system 14A, 24, 34 spacing ring (collision member, annular member, spacing ring member) 14a, 34c circulation groove 14b, 24a, 34a, 34b through hole 15 lens barrel (casing) 15a introduction hole 15c Inlet 16 Gas supply device 19 Filter IL Exposure light (exposure energy) IU Illumination system unit L1 to L3 Lens PL Projection optical system PU Projection system unit R Reticle (mask) W Wafer (substrate)

Claims (12)

[Claims] 1. An optical device for accommodating an optical member in a casing, wherein when a gas supplied from a gas supply device at a predetermined flow rate flows into the casing, the flow rate of the gas is set to be lower than the predetermined flow rate. An optical device comprising a gas inflow mechanism for lowering. 2. The optical device according to claim 1, wherein the gas inflow mechanism is disposed in the casing. 3. The casing has an inlet for guiding gas supplied from the gas supply device into the inside, and the gas inflow mechanism is disposed between the inlet and the surface of the optical member. The optical device according to claim 1, further comprising a collision member configured to collide the gas guided from an inlet. 4. A gas inflow mechanism for housing an optical member in a casing, wherein the gas inflows from a plurality of locations around the optical member when gas flows from the gas supply device into the casing. An optical device comprising: 5. The gas inflow mechanism includes an annular member surrounding the optical member and disposed in the casing, wherein the annular member is opposed to the gas inlet formed in the casing. 5. A flow groove formed along a circumferential direction on a surface to be formed, and a plurality of through holes arranged apart from each other in the circumferential direction in the flow groove.
The optical device according to any one of the above. 6. The optical device according to claim 5, wherein the through hole is arranged at a position shifted from the inlet. 7. The optical device according to claim 5, wherein the annular member is an interval ring member disposed between the adjacent optical members to regulate an interval between the optical members. 8. The optical device according to claim 1, wherein the gas inflow mechanism has a filter that circulates the inflowing gas and adsorbs impurities in the gas. 9. An exposure apparatus for guiding exposure energy to a mask to form a pattern on the mask on a substrate, comprising: the optical apparatus according to claim 1; An exposure apparatus, comprising at least one of an optical system for guiding the exposure energy to the mask or an optical system for guiding the pattern to the substrate via an optical member. 10. A gas inflow method for flowing a gas supplied at a predetermined flow rate from a gas supply device into a casing accommodating an optical member. Is reduced below the predetermined flow rate. 11. A gas inflow method for flowing gas into a casing containing an optical member, wherein the gas is flowed from a plurality of locations around the optical member. 12. An optical device for housing an optical member in a casing, wherein an impurity generated between the gas supply device and the casing when a gas supplied from a gas supply device flows into the casing. An optical device, comprising: a filter that removes a gas from the gas.