JP2002050568A - Exposure method, method for manufacturing device using the method, aligner, and method for manufacturing device using the aligner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve anti-contamination effects, exposure light transmittance and running cost by effectively reducing a generation of an impure substance or ozone in a method for exposing, in a method for manufacturing a device using the same, in an aligner and in an apparatus for manufacturing a device using the same. SOLUTION: The method for exposing comprises the steps of supplying gas, to at least one space formed between an exposure energy generation source 1 and a substrate W, and of regulating a flow rate of the gas suppled to the space, in response to incident conditions of an exposure energy IL incident to the space. Thus, the gas flow rate can be suitably controlled, to fully prevent generation of the ozone or adhesion of impure substance in response to the incident conditions, the contamination can be effectively prevented in response to the incident conditions of the exposure energy, and a waste of the gas supply amount can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure method in a process of manufacturing a fine circuit pattern of a semiconductor integrated circuit, a liquid crystal display or the like, a method of manufacturing a device using the same, an exposure apparatus and a device using the same. Related to a manufacturing apparatus.

[0002]

2. Description of the Related Art When manufacturing a semiconductor element or a liquid crystal display element by a photolithography process, a pattern image of a reticle is projected (shot) on a wafer coated with a photosensitive material (resist) via a projection optical system. A projection exposure apparatus that projects onto an area is used. The circuit in the semiconductor element is transferred by exposing a circuit pattern on a wafer by the projection exposure apparatus, and is formed by post-processing. An integrated circuit is obtained by repeatedly laminating about 20 such circuit wirings.

In recent years, high-density integration of integrated circuits, that is, miniaturization of circuit patterns has been promoted. For this reason, the projection light in the projection exposure apparatus also tends to have a shorter wavelength. That is, a KrF excimer laser (248 nm) has been used in place of the emission line of a mercury lamp, which has been the mainstream until now, and the practical use of a shorter wavelength ArF excimer laser (193 nm) is entering the final stage.
Also, with the aim of higher density integration F ₂ laser (1
(57 nm).

Generally, ultraviolet light having a wavelength of about 190 nm or less is called vacuum ultraviolet light, and does not pass through the air. This is because light is absorbed by substances (hereinafter, referred to as light absorbing substances) such as oxygen molecules, water molecules, and carbon dioxide molecules contained in the air. Further, if the light absorbing material is non-uniform in the optical path space, the illuminance on the wafer will be non-uniform when exposing the circuit pattern. For this reason, in an exposure apparatus using vacuum ultraviolet light, in order to make the exposure light reach the wafer surface with sufficient illuminance and sufficient illuminance uniformity, the amount of light-absorbing substances on the exposure optical path is reduced, and the vacuum ultraviolet light is used. It is preferable to realize high-purity purging with an inert gas (nitrogen, helium, argon, or the like) in which the absorption of exposure light can be ignored.

[0005] One is "initial gas replacement", that is, gas replacement between a large amount of residual air and purge gas that is sealed in the apparatus during assembly and adjustment. The other is “gas purity maintenance”, that is, a constant purge gas flow during exposure. In “Gas purity maintenance”, it should not be necessary if “Initial gas replacement” has been completed. However, the purity of the purge gas in the optical path space is due to degassing from the inner wall of the optical path space or leakage of non-purge gas due to leakage. Decreases,
There is a concern that the illuminance of the exposure light may be reduced. In order to prevent this, in "gas purity maintenance", a high-purity purge gas is constantly flowed even during exposure of the circuit pattern,
Eliminate impurities.

As a measure for measuring the purity of the purge gas in the optical path space, oxygen molecules contained in a large amount in the air in "initial gas replacement", and water molecules desorbed from the inner wall of the optical path space in large amounts in "maintaining gas purity", or It is necessary to maintain the amount of each oxygen molecule at about several ppm or less as a monitor of external air leak. In general, “initial gas replacement” consumes a large amount of purge gas per unit time, but “maintain gas purity” consumes a small amount of purge gas per unit time, and “initial gas replacement” occurs after opening the optical path space of the exposure apparatus. It is only necessary to purge only during the exposure of the circuit pattern in "maintaining gas purity".

[0007]

As described above, in the case of vacuum ultraviolet light, since it is absorbed by oxygen molecules, water molecules, carbon dioxide molecules and the like contained in the air, the exposure light is exposed on the wafer surface via the reticle. It is not easy to reach with sufficient illuminance, which causes a reduction in element manufacturing speed (throughput) and device operation rate. For this reason, it is necessary to reduce or eliminate the light absorbing material on the exposure light path at a higher speed. Normally, if the gas is left undisturbed, it will be homogenized by diffusion, but it will be slow in an atmospheric pressure environment, which may cause a decrease in throughput. If the pressure is reduced, the diffusion by the movement of the molecules is performed faster. However, the device itself (or the optical path space) needs to have a pressure-resistant structure, which not only makes the device heavy and complicated, but also increases the cost.

In both of the conventional "initial gas replacement" and "gas purity maintenance" described above, swirling of purge gas in the lens chamber and stagnation of light-absorbing substances (air and the like) on the walls of the fine structure occur. As a result, it has been difficult to sufficiently reduce / eliminate the light-absorbing substance and increase the uniformity. For example, a lens barrel of a projection optical system has a substantially axially symmetric structure in which a plurality of lenses are arranged. Since the axial direction of the cylindrical lens chamber inside the lens barrel is parallel to the direction of the exposure optical axis, it is difficult to install a device other than the optical member in this axial direction, and it is difficult to install a device other than the optical member on the side wall of the lens barrel. A purge gas supply port and an exhaust port must be provided. In such a situation, the bias gas flow tends to be biased, and local gas tends to stay. Furthermore, high-purity purge gas is generally expensive, and its consumption is a problem related to the running cost of the exposure apparatus. In an exposure apparatus using vacuum ultraviolet light in which the entire exposure optical path space must be purged, the running cost for the purge gas is large, and reduction of the cost is an important issue. Accordingly, the exposure apparatus using vacuum ultraviolet light such as F ₂ laser light, sufficient illuminance and the circuit pattern while maintaining the illuminance uniformity to burn on the wafer, so that there is no accumulation of localized light absorbing materials In order to realize a sufficiently low light-absorbing substance concentration and non-uniform light-absorbing substance concentration, it is necessary to efficiently perform gas replacement (removal of the light-absorbing substance).

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and does not exhaust air under reduced pressure in each part on an exposure light path, particularly in a lens chamber, and does not reduce the concentration (purge purity) and concentration of a light-absorbing substance in an optical path space. It is an object of the present invention to provide an exposure method, a device manufacturing method using the same, and an exposure apparatus and a device manufacturing apparatus using the same, which can make uniformity faster and reduce the consumption of purge gas. .

[0010]

The present invention has the following features to attain the object mentioned above. That is, with reference to FIGS. 1 to 11, in the exposure method of the present invention, the exposure energy (IL) from the exposure energy source (1) is guided to the mask (R), and the pattern of the mask is transferred to the substrate ( An exposure method for transferring the gas to at least one space (S) formed between the exposure energy generation source and the substrate, and changing a flow of the gas in the space. It is characterized by making it. The exposure apparatus of the present invention is an exposure apparatus that guides exposure energy (IL) from an exposure energy source (1) to a mask (R) and transfers a pattern of the mask onto a substrate (W). A gas supply mechanism (16) for supplying a gas to at least one space (S) formed between the exposure energy generation source and the substrate, and a gas flow variable mechanism for changing a flow of the gas in the space ( 17, 21, 3
1, 41).

In these exposure methods and exposure apparatuses, a gas is supplied to at least one space (S) formed between the exposure energy generating source (1) and the substrate (W), and the gas in the space is supplied. Since the flow of the (purge gas) is changed, the flow of the gas is not a monotonous and uniform flow but a fluctuating flow, and more effective stirring and replacement are performed to prevent stagnation, and the space (lens) is prevented. , Etc.), the reduction or elimination of the light-absorbing substance concentration and the concentration non-uniformity can be performed more efficiently and at high speed.

In the exposure method and the exposure apparatus according to the present invention, means (19, 20, 22) for changing a gas flow path in the space (S) by changing a gas flow path; Means (3) for changing the flow rate of gas supplied to
2) means (41) for changing the flow of gas by changing the number of at least one of an inlet for supplying gas into the space or an outlet for exhausting gas from the space; It is preferable to adopt at least one of means (41) for changing the position of at least one of an air supply port for supplying gas or an exhaust port for exhausting gas from the space to change the gas flow. According to these means, it is easy to make the gas flow in the space unsteady.

Further, the exposure method and the exposure apparatus of the present invention are suitable when the exposure energy (IL) is, in particular, vacuum ultraviolet light. This is because, in the case of vacuum ultraviolet light, oxygen molecules and water molecules in the air become light-absorbing substances, so that it is necessary to sufficiently and efficiently agitate and replace the inside of the optical path space with the purge gas.

Further, in the exposure apparatus according to the present invention, the space is provided in the illumination optical system (LO) for guiding the exposure energy (IL) to the mask (R) and irradiating the mask with the mask or under the exposure energy. It is preferably at least a part of the space in the projection optical system (PL) that transfers the upper pattern to the substrate (W). That is, since the illumination optical system and the projection optical system are constituted by a plurality of lenses and have a lens chamber partitioned by the lenses, local stagnation of the purge gas is likely to occur, and in particular, a space that requires stirring and replacement of the purge gas. That's why.

The method for manufacturing a device according to the present invention is a method for manufacturing a device manufactured through a transfer step of transferring a pattern of a mask (R) onto a substrate (W). Performing a process. Further, a device manufacturing apparatus of the present invention is a device manufacturing apparatus manufactured by transferring a pattern of a mask (R) onto a substrate (W), and includes the exposure apparatus of the present invention. .

In the device manufacturing method and device manufacturing apparatus, since the above-described exposure method or the above-described exposure apparatus is provided, the consumption of the purge gas can be reduced, the running cost can be reduced, and the exposure accuracy can be improved to improve the accuracy. Device can be manufactured.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of an exposure method according to the present invention, a device manufacturing method using the same, an exposure apparatus and a device manufacturing apparatus using the same will be described with reference to FIGS. It will be described with reference to FIG.

FIG. 1 is a diagram schematically showing the overall configuration of an exposure apparatus (device manufacturing apparatus) according to the present embodiment. The exposure apparatus is provided with an exposure light source (exposure energy generation source).
1 is, for example, a step-and-scan type projection exposure apparatus for manufacturing a semiconductor element (device) having an F ₂ excimer laser that emits exposure light (exposure energy) IL of vacuum ultraviolet light (wavelength: 157 nm).

In this exposure apparatus, the exposure light IL emitted from the exposure light source 1 is incident on the deflection mirror 2a in the illumination optical system LO. The illumination optical system LO receives the fly-eye lens 3, the transmission mirror 6, the integrator sensor 7a that receives the exposure light IL reflected from the transmission mirror 6 and monitors the exposure energy, and reflects the light from the optical system after the transmission mirror 6 and the like. The returning exposure light IL is transmitted through the transmission mirror 6.
Monitor 7 for monitoring the reflectance by receiving light through the
b, a deflection mirror 2b, a relay lens 8, a blind 9, a condenser lens 10, and the like. That is, the exposure light IL reflected from the deflecting mirror 2a passes through the fly-eye lens 3, the transmission mirror 6, the deflecting mirror 2b, the relay lens 8, the blind 9, and the relay lens 10 in this order, and is incident on the deflecting mirror 2c. .

Exposure light IL reflected by deflection mirror 2c
Is a two-dimensionally movable reticle stage RST supported in the reticle chamber 11 via the condenser lens 100.
The light is incident on the upper reticle (mask) R. Further, exposure light IL that has passed through reticle R is incident on projection optical system PL, passes through a plurality of lens elements constituting projection optical system PL, and is on wafer stage WST designated in wafer chamber 12. Incident on a wafer (substrate) W and a reticle R
The upper pattern image is formed on the surface of the wafer W.

The wafer W is placed on a sample stage 13 on a wafer stage WST which is movable in a three-dimensional direction (XYZ directions).
And the positions of reticle stage RST and wafer stage WST in the XY plane are
The laser beam is incident on an interferometer mirror (not shown) provided on each of the ST and wafer stage WST (not shown), and is measured by being reflected by a laser beam from the laser interferometer (not shown). Then, reticle stage RST and wafer stage WST are synchronously moved at the time of exposure, and a pattern is exposed on wafer W by a so-called step-and-scan method.

In the exposure apparatus of this embodiment, the illumination optical system L
O, reticle chamber 11, projection optical system PL and wafer chamber 1
2. Further, each lens chamber in the illumination optical system LO and the projection optical system PL has a structure in which the airtightness is improved as compared with the related art. The integrated luminous intensity and reflectivity of the exposure light are measured and monitored by the integrator sensor 7a and the reflectivity monitor 7b, and the measured value is sent as a signal to the control system C, and the illuminance at the time of printing on the wafer W is measured. You can now know. The structure with enhanced sealing described here means that there is no gas flow between the internal space in the reticle chamber 11, the wafer chamber 12, the lens chamber of each optical system, and the external space surrounding them, or There is a gas flow between the space and the external space, but in a state in which the flow of gas from the external space to the internal space is suppressed, for example, the pressure of the internal space is set so that the gas flows out of the internal space to the external space. Indicates that the pressure is set higher than the pressure of the external space.

The illumination optical system LO, the reticle chamber 11,
The projection optical system PL and the wafer chamber 12 are connected to a densitometer 14 for measuring the concentration (purge purity) of the light absorbing substance in the optical path space, and the measured value is sent to the control system C as a signal. ing. Furthermore, the illumination optical system LO, the reticle chamber 11, the projection optical system PL, and the wafer chamber 12
A vacuum pump 15 for sucking the internal gas is connected through these exhaust ports, and the vacuum pump 15 is controlled by the control system C. Further, the illumination optical system LO and the projection optical system P
L includes a gas supply mechanism 16 for supplying a purge gas to an internal lens chamber (space) S, as shown in FIGS.
And a gas flow variable mechanism 17 for changing the flow of the purge gas in the lens chamber S. The gas supply mechanism 16 and the gas flow variable mechanism 17 are also controlled by the control unit C.

The gas supply mechanism 16 is provided with an inert gas regulator for adjusting the flow rate into the lens chamber S and supplying an inert gas as a purge gas (a gas through which exposure light such as nitrogen, helium, and argon passes). Gas source,
The supply port 18 of the lens chamber S is provided by the purge gas supply pipe 16a.
It is connected to the. The variable gas flow mechanism 17 is provided at an air supply port 18, and includes a movable air supply nozzle (flow path variable mechanism) 19 and a distal end opening portion starting from a base end of the movable air supply nozzle 19. A nozzle drive unit (flow path variable mechanism) 20 that alternately moves the upper and lower sides 19 a and changes the direction of the movable air supply nozzle 19 is provided. The air supply port 18 is formed so as to be gradually expanded toward the inside of the lens chamber S in order to secure a space in which the movable air supply nozzle 19 can move. The movable air supply nozzle 19 is configured to alternately drive the tip opening 19a vertically and horizontally by a built-in motor.

Next, the exposure method in this embodiment will be described.

First, in each of the above-mentioned "initial gas replacement" and "maintaining gas purity", the hermeticity of each lens chamber S of the illumination optical system LO and the projection optical system PL is enhanced to reduce the absorption of light-absorbing substances from the outside. Shut off inflow. Next, the control unit C controls the vacuum pump 15, the gas supply mechanism 16 and the gas flow variable mechanism 17 so that a high-purity purge gas flows into each of the lens chambers S under a constant pressure to remove the gas inside. Do. That is, the purge gas is supplied from the gas supply mechanism 16 into the lens chamber S via the purge gas supply pipe 16 a and the movable air supply nozzle 19.

At this time, the purge gas is blown out in the direction toward the movable air supply nozzle 19, but the controller C controls the nozzle drive unit 20 of the gas flow variable mechanism 17 to change the direction of the movable air supply nozzle 19. By changing it every moment, the purge gas can take an unsteady flow path, and the lens chamber S
The local stagnation of the light-absorbing substance can be reduced, and a faster reduction of the light-absorbing substance concentration can be realized. As described above, the inside of the lens chamber S is sufficiently stirred with the purge gas, and after the gas replacement, the exposure is performed.

It should be noted that the densitometer 14 measures the concentration of the light-absorbing substance and the non-uniformity of the concentration regardless of whether the light-shielding pattern formed on the mask is being exposed to the photosensitive substrate, and monitors these values. Alternatively, when the value becomes equal to or more than the allowable value, the operation of exposing the light-shielding pattern may be stopped, and the operation for reducing the concentration of the light-absorbing substance or the concentration non-uniformity may be automatically performed. In addition, the history of the light-absorbing substance concentration and the concentration non-uniformity are monitored by one or a plurality of densitometers 14 and the work of reducing the above-mentioned light-absorbing substance concentration or the like when it is expected to exceed the allowable value or earlier. May be automatically performed. The fact that automation is possible and that it is effective is the same in the following embodiments.

As described above, in the present embodiment, the non-stationary purge gas flow is generated by the variable gas flow mechanism 17, so that the stagnation of the light absorbing substance can be further reduced. For this reason, the concentration of the light-absorbing substance and the non-uniformity of the concentration can be reduced more efficiently, so that the consumption of the purge gas can be reduced. In particular, in the case of exposure using an F ₂ laser as in the present embodiment, gases such as helium, argon, and nitrogen can be considered as substances having no light-absorbing substance. However, these high-purity gases are generally expensive, and purge gas is generally used. In this embodiment, which consumes less, the running cost of the exposure apparatus can be further reduced.

In the present method, the agitation of the gas inside the lens chamber S by the purge gas is promoted, whereby a faster reduction of the light-absorbing substance can be realized, so that the working speed can be improved. Further, even during exposure of the light-shielding pattern, it is possible to reduce the concentration of the light-absorbing substance and the non-uniformity of the concentration, and there is an advantage that the throughput is not reduced. Furthermore, since the gas replacement is performed under a constant pressure close to the atmospheric pressure, it is not necessary to make the device a pressure-resistant structure, and the device can be made lightweight and inexpensive. In addition, since retention of impurities can be reduced and impurities can be efficiently discharged, non-uniformity of illuminance (non-uniformity of line width) is reduced.

Next, a second embodiment of the present embodiment will be described with reference to FIGS.

The difference between the second embodiment and the first embodiment is that the gas flow variable mechanism 17 of the first embodiment changes the direction by the nozzle driving unit 20 to change the gas flow path into the lens chamber S. In contrast to the provision of the movable air supply nozzle 19, the gas flow variable mechanism 21 according to the second embodiment has a movable air supply nozzle that changes the gas flow path by the pressure of the purge gas, as shown in FIG. An eccentric top nozzle (flow path variable mechanism) 22 is provided.

That is, in the present embodiment, a substantially conical eccentric top nozzle 22 along the shape of the air supply port 18 is installed in the air supply port 18 so as to be rotatable about a rotation axis 22a as a central axis. As shown in FIGS. 4 and 5, the eccentric top nozzle 22 has a purge gas inlet 22b formed near the rotation shaft 22a at a connection portion with the purge gas supply pipe 16a, and a purge gas outlet facing the lens chamber S. 22c
Are formed at positions offset from the rotation shaft 22a.

Therefore, when the high-purity high-purity purge gas is supplied from the gas supply mechanism 16 to the eccentric top nozzle 22 in the air supply port 18 via the purge gas supply pipe 16a, the purge gas flowing from the purge gas inlet 22b is purged. The gas is blown into the lens chamber S from the purge gas outlet 22c through a purge gas flow path 22d in the eccentric top nozzle 22 connecting the inlet 22b and the purge gas outlet 22c.

At this time, the eccentric top nozzle 22 is rotated by the momentum of the gas molecules of the purge gas flowing through the purge gas flow path 22d, and the purge gas outlet 22c is connected to the rotating shaft 22a.
, The purge gas flow path into the lens chamber S fluctuates. Therefore, also in this case, the lens chamber S
The gas inside can be further stirred and gas can be efficiently replaced. When the center of gravity of the eccentric top nozzle 22 is offset from the rotation shaft 22a (center axis), the nozzle can be rotated more efficiently.

Next, a third embodiment of the present invention will be described with reference to FIGS.

The difference between the third embodiment and the first embodiment is that the variable gas flow mechanism 17 of the first embodiment has a movable air supply nozzle 19 for changing the flow path of the purge gas. The variable gas flow mechanism 31 of the second embodiment is similar to that of FIG.
As shown in (1), there is a variable flow rate valve (variable flow rate mechanism) 32 for changing the flow rate of the purge gas flowing into the lens chamber S.

That is, in the present embodiment, a variable flow rate valve 32 such as a ball valve or a needle valve is provided in the purge gas supply pipe 16a near the air supply port 33, and the degree of opening is controlled by the control of the control system C. The flow rate of the purge gas flowing from the air port 33 can be arbitrarily adjusted. As described above, the flow control valve 3 is controlled by the control system C.
The flow rate of the inflowing purge gas is changed by changing the opening degree of the lens 2 every moment, the flow path of the purge gas in the lens chamber S fluctuates irregularly, and the stirring of the gas inside is further promoted. Retention is further reduced. As another example of this embodiment, as shown in FIGS. 7 and 8, a variable flow rate restrictor (variable flow rate mechanism) 34 that makes the inner diameter of the purge gas supply pipe 16 a variable is used to supply purge gas near the air supply port 33. The same effect can be obtained by providing the tube 16a.

Next, a fourth embodiment of the present embodiment will be described.

The difference between the fourth embodiment and the third embodiment is that the gas flow variable mechanism 31 of the third embodiment is different from the lens chamber S in the third embodiment.
In contrast to changing the flow rate of the purge gas flowing into the lens chamber, the gas flow variable mechanism (variable flow rate mechanism) of the fourth embodiment changes the flow rate of the purge gas flowing into the lens chamber. That is, in the present embodiment, the flow rate of the purge gas into the lens chamber S is changed by controlling the gas supply mechanism 16 and the like by the control system C. At this time, similarly to the case where the flow rate into the lens chamber S is changed, even if the flow rate of the purge gas is changed, the stirring and replacement of the internal gas can be performed more efficiently.

For example, when the gas supply mechanism 16 supplies a purge gas from a cylinder or supplies a purge gas from a pipe laid in a factory, the high-purity purge gas is usually supplied at a high pressure. The purge gas is pressurized to a maximum of 100 atm or more, and in the latter case to about 5 atm. Therefore, when injecting into the optical path space of 1 atm (lens chamber), it is usually 2 to 2 through the regulator.
The pressure is reduced to 3 atm before injection. Generally, the regulator can set an arbitrary secondary pressure.

Therefore, in the present embodiment, the secondary pressure of the regulator is controlled by the control system C as a function of time so that the secondary pressure always fluctuates.
This causes the purge gas flow rate to fluctuate.
When the secondary pressure is high, the purge gas inflow speed is increased, so that the purge gas can reach and be stirred far from the air supply port of the lens chamber S, and when the secondary pressure is low, the purge gas inflow speed can be increased. Therefore, the vicinity of the air supply port is intensively stirred, the flow path of the purge gas in the lens chamber becomes unstable, and the gas can be further agitated. The vacuum pump 15 is controlled to control the lens chamber S
By changing the discharge speed of the purge gas from the lens chamber, the flow speed of the purge gas into the lens chamber S can be changed, and the same effect can be obtained.

Next, a fifth embodiment of the present invention will be described with reference to FIGS.

The difference between the fifth embodiment and the third embodiment is that the gas flow variable mechanism 31 of the third embodiment is different from the fifth embodiment in that the lens chamber S
The flow rate of the purge gas flowing into the inside is controlled by the flow rate variable valve 32.
By changing the degree of opening of the
Variable gas flow mechanism (supply / exhaust port number changing mechanism) 41 of the embodiment
As shown in FIGS. 9 and 10, a plurality of air inlets 42 and air outlets 43 are provided in one lens chamber S to open and close air inlets 42 and air outlets 43 arranged at arbitrary positions as needed. That is, the gas flow path in the lens chamber S is changed.

That is, in the exposure apparatus of this embodiment, for example, the air supply port 42 and the air
The control system C is provided with a gas flow variable mechanism 41 for opening and closing the supply port 42 and the exhaust port 43 at an arbitrary number and an arbitrary position at any time by the control system C. Therefore, if any air supply port 42 and exhaust port 43 are kept open, the flow of the purge gas becomes steady, and the light-absorbing substance stagnates in the shadow of the flow path. On the other hand, in the present embodiment, an arbitrary supply / exhaust port is opened and closed at any time while changing the number and position of the openings, whereby the flow path of the purge gas is not determined, and an unsteady gas flow can be realized.

Thus, the gas in the lens chamber S can be better stirred, and the stagnation of the light absorbing material can be further reduced. The opening and closing of the air supply port 42 and the air exhaust port 43 may be achieved by installing a highly sealed electromagnetic valve or electric valve at each air supply / exhaust port. In addition, a general random number generation algorithm is used to determine the supply / exhaust port to open / close.
It can be easily realized by incorporating it into In addition,
With the number of air supply / exhaust ports intact, even if an optional air supply / exhaust port is opened, the air supply / exhaust port position changing mechanism that performs the work of closing the same number of any other air supply / exhaust ports in the control system C,
As described above, the gas in the lens chamber S is further stirred.

The present invention includes the following embodiments. In the above embodiments, the same inert gas is used for “initial gas replacement” and “gas purity maintenance”, but different types of gases may be used. For example, in an exposure apparatus using an F ₂ excimer laser, the optical path space in the projection optical system and the illumination optical system has H
e gas is used, but He gas is expensive,
N ₂ gas may be used in “initial gas replacement”, and He gas may be used in “gas purity maintenance”. In each of the above embodiments, the configuration in which the gas flow variable mechanism is provided in the lens chamber has been described. However, the gas flow variable mechanism described in each embodiment can be applied to the wafer chamber and the reticle chamber, and the wafer chamber and the reticle chamber can also be used. Similarly, higher gas displacement efficiency can be obtained.

In each of the above embodiments, the vacuum pump 1
Although the gas in the space in the projection optical system PL and the illumination optical system LO is sucked in 5, for example, a cryopump may be used. The cryopump is a type of vacuum pump, and is a type in which a solvent such as activated carbon or synthetic fluoride is cooled with a refrigerant such as nitrogen.
5K), a cooled surface (cryopanel) is placed on this surface, and a gas other than H ₂ , He, or Ne, for example, N ₂ , A
r, O ₂ , H ₂ O, CO _2, etc.) to create a high vacuum.

In each of the above embodiments, nitrogen gas, helium, and argon are used as the gas to be supplied.
An inert gas such as neon, krypton, xenon, and radon may be used. In each of the above embodiments, one or two types of gas flow variable mechanisms are employed,
The gas flow variable mechanisms of other embodiments may be used in combination. Therefore, with such a configuration, it is possible to reduce a device manufacturing speed (throughput) due to a decrease in illuminance, a light-shielding pattern exposure waiting time, and a line width abnormal value (ΔCD) due to non-uniform illuminance. . As a result, the operating speed of the manufactured element can be reduced and the probability of malfunction can be reduced. Further, the consumption of the purge gas can be reduced, and the running cost of the exposure apparatus can be reduced.

The exposure apparatus of the above embodiment can also be applied to a proximity exposure apparatus for exposing a mask pattern by bringing a mask and a substrate into close contact with each other instead of a reticle without using a projection optical system. The application of the exposure apparatus is not limited to an exposure apparatus for semiconductor manufacturing, but an exposure apparatus for manufacturing other devices, for example, a liquid crystal exposure apparatus that exposes a liquid crystal display element pattern to a square glass plate, It can be widely applied to an exposure apparatus for manufacturing a thin film magnetic head.

In this embodiment, the light source of the exposure apparatus is
F ₂ laser (157 nm) as well, g line (436N
m), i-line (365 nm), KrF excimer laser (2
48 nm), ArF excimer laser (193 nm), F
_The light source and the X-ray may have a shorter wavelength than the _two lasers.
The magnification of the projection optical system may be not only a reduction system but also an equal magnification or an enlargement system.

When an F ₂ laser or X-ray is used as the projection optical system, a catadioptric or refractive optical system is used (a reticle is of a reflection type), and far ultraviolet rays such as other excimer lasers are used. When used, a material that transmits far ultraviolet rays, such as quartz or fluorite, is used as the glass material.

In the exposure apparatus of this embodiment, the mask and the substrate are stationary, and the pattern of the mask is exposed and the substrate is sequentially moved step by step.
The present invention can also be applied to a repeat type exposure apparatus. In addition, the exposure apparatus of the present embodiment can be applied to a proximity exposure apparatus that exposes a mask pattern by bringing a mask and a substrate into close contact without using a projection optical system.

The application of the exposure apparatus is not limited to an exposure apparatus for manufacturing semiconductors. For example, an exposure apparatus for liquid crystal for exposing a liquid crystal display element pattern on a square glass plate and a thin film magnetic head are manufactured. Widely applicable to an exposure apparatus. When a linear motor is used for a wafer stage or a reticle stage, any of an air levitation type using an air bearing and a magnetic levitation type using Lorentz force or reactance force may be used. The stage may be of a type that moves along a guide or a guideless type that does not have a guide.

When a plane motor is used as the stage driving device, one of the magnet unit (permanent magnet) and the armature unit is connected to the stage, and the other of the magnet unit and the armature unit is connected to the stage moving surface side. (Base). The reaction force generated by the movement of the wafer stage may be mechanically released to the floor (ground) using a frame member as described in JP-A-8-166475. The present invention is also applicable to an exposure apparatus having such a structure.

The reaction force generated by the movement of the reticle stage may be mechanically released to the floor (ground) by using a frame member as described in Japanese Patent Application Laid-Open No. 8-330224. The present invention is also applicable to an exposure apparatus having such a structure.

As described above, the exposure apparatus according to the embodiment of the present invention converts various subsystems including the components described in the claims of the present application into predetermined mechanical accuracy, electrical accuracy,
It is manufactured by assembling to maintain optical accuracy. 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 electric systems to ensure these various accuracy Are adjusted to achieve electrical accuracy. The process of assembling the various subsystems into the exposure apparatus includes mechanical connection, wiring connection of an electric circuit, and piping connection of a pneumatic circuit between 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. When the process of assembling the various subsystems into the exposure apparatus is completed, comprehensive adjustment is performed, and various precisions of the entire exposure apparatus are secured. It is desirable that the exposure apparatus be manufactured in a clean room in which the temperature, cleanliness, and the like are controlled.

The semiconductor device, as shown in FIG.
Step 201 for designing the function and performance of the device, Step 202 for manufacturing a mask (reticle) based on this design step, Step 203 for manufacturing a wafer from a silicon material, and using the exposure apparatus of the above-described embodiment to pattern the reticle Processing step 204 for exposing to light, device assembling step (dicing step,
(Including a bonding step and a package step) 205, an inspection step 206, and the like.

[0059]

According to the present invention, the following effects can be obtained.
According to the exposure method and the exposure apparatus of the present invention, a gas is supplied to at least one space formed between an exposure energy generation source and a substrate, and a gas flow in the space is changed. The reduction of the light-absorbing substance concentration in the space and its non-uniformity can be realized more quickly and reliably. In other words, the reduction of the light-absorbing substance concentration and the concentration non-uniformity can reduce the illuminance reduction and the illuminance non-uniformity (illuminance non-uniformity), respectively. Time can be reduced.

In the exposure apparatus of the present invention, the variable gas flow mechanism changes a gas flow path in the space to change a gas flow, and a gas flow variable mechanism changes a gas flow in the space. The number of at least one of a variable flow rate mechanism or a variable flow rate mechanism that changes a gas flow by changing a flow rate or an inflow speed, an air supply port that supplies gas into the space, or an exhaust port that exhausts gas from the space. A gas supply / exhaust port number changing mechanism that changes the gas flow by changing the position of at least one of an air supply port that supplies gas into the space or an exhaust port that exhausts gas from the space, and the gas flow. Since at least one of the air supply / exhaust port position change mechanisms for changing the air pressure, the gas flow path in the space can be in an unsteady state in any of the above-described mechanisms, which is relatively simple. Structure It is possible to perform stirring and replacement of the gas in the in the space of the lens chamber and the like.

According to the device manufacturing method and device manufacturing apparatus of the present invention, since the above-described exposure method or the above-described exposure apparatus is provided, the consumption of purge gas can be reduced, the running cost can be reduced, and the exposure accuracy can be improved. A device such as a semiconductor element can be manufactured with high accuracy, and the quality and reliability of the device can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic overall configuration diagram showing an exposure apparatus in a first embodiment of an exposure method according to the present invention, a device manufacturing method using the same, and an exposure apparatus and a device manufacturing apparatus using the same. is there.

FIG. 2 is a cross-sectional view of a main part showing a gas flow variable mechanism in a first embodiment of an exposure method according to the present invention, a device manufacturing method using the same, and an exposure apparatus and a device manufacturing apparatus using the same. It is.

FIG. 3 is a sectional view of a main part showing a gas flow variable mechanism in a second embodiment of an exposure method according to the present invention, a device manufacturing method using the same, and an exposure apparatus and a device manufacturing apparatus using the same. It is.

FIG. 4 is a front view showing an eccentric top nozzle in a second embodiment of the exposure method according to the present invention, a device manufacturing method using the same, and an exposure apparatus and a device manufacturing apparatus using the same.

FIG. 5 is a side view showing an eccentric coma nozzle in a second embodiment of the exposure method according to the present invention, a device manufacturing method using the same, and an exposure apparatus and a device manufacturing apparatus using the same.

FIG. 6 is a cross-sectional view of a main part showing a gas flow variable mechanism in a third embodiment of an exposure method according to the present invention, a device manufacturing method using the same, and an exposure apparatus and a device manufacturing apparatus using the same. It is.

FIG. 7 is a view showing another example of the gas flow variable mechanism in the third embodiment of the exposure method according to the present invention, the device manufacturing method using the same, and the exposure apparatus and the device manufacturing apparatus using the same. It is sectional drawing of a part.

FIG. 8 is a front view showing a flow rate variable aperture in the third embodiment of the exposure method according to the present invention, a device manufacturing method using the same, and an exposure apparatus and a device manufacturing apparatus using the same.

FIG. 9 is a perspective view of a main part showing a gas flow variable mechanism in a fifth embodiment of an exposure method according to the present invention, a device manufacturing method using the same, and an exposure apparatus and a device manufacturing apparatus using the same. It is.

FIG. 10 is a plan view of a main part showing a gas flow variable mechanism in a fifth embodiment of an exposure method according to the present invention, a device manufacturing method using the same, and an exposure apparatus and a device manufacturing apparatus using the same. It is.

FIG. 11 is a flowchart illustrating an example of a manufacturing process of a semiconductor device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Exposure light source (exposure energy generation source) 16 Gas supply mechanism 17, 21, 31, 41 Gas flow variable mechanism 19 Movable air supply nozzle (flow path variable mechanism) 20 Nozzle drive part (flow path variable mechanism) 22 Eccentric frame type Nozzle (variable flow path mechanism) 32 Valve for varying flow rate (variable flow rate mechanism) 34 Throttle for varying flow rate (variable flow rate mechanism) 18, 42 Supply port 43 Supply port C Control system IL Exposure light (exposure energy) LO Illumination optics System PL Projection optical system S Lens room (space) R Reticle (mask) W Wafer (substrate)

Claims (9)

[Claims] 1. An exposure method for guiding exposure energy from an exposure energy source to a mask and transferring a pattern of the mask to a substrate, wherein at least one of the exposure energy sources and the substrate is formed between the substrate and the substrate. An exposure method, wherein a gas is supplied to two spaces and a flow of the gas in the space is changed. 2. A method of manufacturing a device, which is manufactured through a transfer step of transferring a pattern of a mask onto a substrate, wherein the transfer step is performed by the exposure method according to claim 1. . 3. An exposure apparatus for guiding exposure energy from an exposure energy generation source to a mask and transferring a pattern of the mask to a substrate, wherein at least one of the exposure devices formed between the exposure energy generation source and the substrate is provided. An exposure apparatus comprising: a gas supply mechanism that supplies gas to two spaces; and a gas flow variable mechanism that changes a flow of the gas in the space. 4. The exposure apparatus according to claim 3, wherein the variable gas flow mechanism has a variable flow path mechanism that changes a flow path of the gas in the space. 5. The exposure apparatus according to claim 3, wherein the variable gas flow mechanism has a variable flow rate mechanism that changes a flow rate of the gas supplied into the space. 6. The exposure apparatus according to claim 3, wherein the variable gas flow mechanism includes a variable flow rate mechanism that changes a flow rate of the gas into the space. 7. The variable gas flow mechanism has a supply / exhaust port number changing mechanism for changing at least one of an air supply port for supplying the gas into the space and an exhaust port for exhausting the gas from the space. The exposure apparatus according to claim 3, wherein: 8. The supply / exhaust port position changing mechanism for changing at least one of an intake port for supplying the gas into the space and an exhaust port for exhausting the gas from the space. 8. The method according to claim 3, wherein
The exposure apparatus according to any one of the above. 9. A method of manufacturing a device manufactured by transferring a pattern of a mask onto a substrate, wherein the pattern of the mask is transferred onto the substrate by the exposure apparatus according to claim 3. Characteristic device manufacturing method.