JP2001023890A - Aligner and manufacture of device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent or reduce the occurrence of ununiformed temperature gradients in surrounding means, by constituting each surrounding means to at least partially have a heat insulating layer made of a material having a low coefficient of thermal conductivity, and a heat diffusing layer made of a material having a high coefficient of thermal conductivity. SOLUTION: The air circulated in a chamber 20 is conditioned to a fixed temperature by means of a main air conditioner 21. In addition, heat generating sections or spots to be controlled for temperature with high accuracy in the air conditioner 21 are individually controlled for temperature by partial air- conditioning, liquid circulation, etc., and surrounded by means of surrounding means 23. Each surrounding means 23 at least partially has a heat diffusing layer which prevents the occurrence of a local temperature gradient and has a high coefficient of thermal conductivity, and a heat diffusing layer which reduces or eliminates the influence of temperature fluctuation in the inside and outside spaces of the surrounding means 23 and has a low coefficient of thermal conductivity. In addition, the heat diffusing layer is formed by using such a material that has a coefficient of thermal conductivity which is higher than that of the material in the thickness direction in the facial direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus and a device manufacturing method using the same. The present invention relates to an exposure apparatus that performs well exposure and a device manufacturing method using the same.

[0002]

2. Description of the Related Art In recent years, as semiconductor integrated circuits such as ICs and LSIs have become finer and more highly integrated, semiconductor exposure apparatuses have been improved in accuracy and function. In particular, in alignment, a technique of superposing an original plate and a substrate on the order of tens of nanometers is required. Therefore, the alignment apparatus is indispensable to the exposure apparatus for performing the above-described overlay exposure, and in recent years, it has been improved to enable higher precision and higher speed processing.

[0003] It can be said that the positioning device is roughly composed of three element technologies. One is an alignment optical system that optically detects an alignment mark formed in advance on a wafer and obtains a photoelectric signal according to the profile of the mark. The other two are a signal processing system for electrically processing a photoelectric signal obtained by the alignment optical system by an appropriate algorithm to obtain a shift amount of the alignment mark from an original position, and a signal processing system for obtaining a shift amount from the original position. This is a positioning mechanism for precisely correcting the position of the wafer or the position of the mask (or reticle) in accordance with the amount of displacement. In recent years, reduction projection that organically combines these three element technologies, namely, an alignment optical system as an optical technology, a signal processing system as an electronic technology (information processing technology), and a positioning mechanism as a precision mechanical technology in a high-dimensional manner. A mold exposure apparatus (stepper) has been widely used in a semiconductor manufacturing process. Such a stepper forms and projects an optical image of a reticle circuit pattern on a partial area on a wafer by a projection lens having a high resolution.
Then, the stage on which the wafer is mounted is stepped two-dimensionally in the X and Y directions to expose the entire surface of the wafer.

In the case of such a stepper, there are roughly three types of practical forms of the alignment optical system incorporated therein. The first method is a TTR (Through The Reticle) method of simultaneously observing (or detecting) an alignment mark formed on a reticle and an alignment mark on a wafer via a projection lens, and the second method is a method of using a reticle. TTL (Through) which detects only an alignment mark on a wafer via a projection lens without detecting an alignment mark at all.
The third method is an off-axis method in which only an alignment mark on a wafer is detected via a microscope objective lens separately provided from the projection lens by a predetermined distance. In recent years, as the pattern to be transferred onto the wafer has become finer and finer, there has been a demand for further improvement in the alignment accuracy of the wafer and the reticle.

[0005] One of the factors affecting the alignment accuracy of a wafer or a reticle is a temperature change around the alignment optical system. That is, due to a temperature change around the alignment optical system, air fluctuations occur in the atmosphere around the alignment optical system, and the focal position, projection magnification, and the like of the lens change. To cope with this, in a conventional exposure apparatus, a method of surrounding the alignment optical system with surrounding means, or a method of air-conditioning the alignment optical system is used. For example, JP-A-10-135
According to the invention described in JP-A-117, at least a part of the position detecting means for detecting the position of the photosensitive substrate is surrounded by the surrounding means having predetermined airtightness, and a part of the gas existing in the surrounding means is removed. The temperature of the gas around the position detecting means is controlled by suction.

[0006]

However, according to this prior art, there is a problem that the structure of the alignment unit becomes complicated because it is necessary to newly form a suction unit. There is also a problem that the air in the surrounding means is disturbed by sucking a part of the gas present in the surrounding means.

Further, when an atmosphere having a heat source or a temperature gradient exists outside the surrounding means, the internal temperature does not fluctuate instantaneously, but heat is gradually transferred to the surrounding means to increase the internal temperature. Especially depending on the location of the external heat source,
A non-uniform temperature gradient is generated in the surrounding means, and a non-uniform temperature gradient is also generated inside. The non-uniform temperature gradient contributes to air fluctuations in the optical optical path, and deteriorates the performance and alignment accuracy of the exposure apparatus.

Further, when there is a heat source and an atmosphere having a temperature gradient inside the enclosing means, external temperature fluctuation does not occur instantaneously, but heat is gradually transferred to the enclosing means to cause external temperature fluctuation. . Particularly, depending on the position of the internal heat source, a non-uniform temperature gradient is generated in the surrounding means, and a non-uniform temperature gradient is also generated outside. The non-uniform temperature gradient contributes to air fluctuations and the like in the optical path, and deteriorates the performance and alignment accuracy of the exposure apparatus.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to prevent an exposure apparatus and a device manufacturing method using the same from generating an uneven temperature gradient in surrounding means. In other words, the position of the substrate can be always detected with a stable accuracy, and further, a pattern that is becoming finer in recent years or in the future can be exposed with a high overlay accuracy. is there.

[0010]

In order to achieve this object, a first exposure apparatus of the present invention is an exposure apparatus for exposing a pattern of an original onto a substrate via a projection optical system. Surrounding means, at least partially comprising a heat insulating layer composed of an object having low thermal conductivity and a heat diffusion layer composed of an object having high thermal conductivity. It is characterized by the following.

A second exposure apparatus is the first exposure apparatus, wherein the surrounding means is a position of the original plate, the substrate, a stage that moves while holding the original plate, or a position of the stage that moves while holding the substrate. And at least a part of a light path of an optical system included in the exposure apparatus, a light source for exposure, or a heat source included in the exposure apparatus.

In the third exposure apparatus, in the second exposure apparatus, when the surrounding means surrounds at least a part of the optical path of the position detecting means or the optical system, the surrounding means is provided on the inner wall. It is characterized by having a heat insulating layer composed of an object having a low thermal conductivity in a part and a heat diffusion layer composed of an object having a high thermal conductivity in a part of an outer wall.

In a fourth exposure apparatus, in the exposure apparatus according to the second or third aspect, when the surrounding means surrounds at least a part of the exposure light source or the heat source, the surrounding means is A heat insulating layer formed of an object having a low thermal conductivity on a part of an outer wall, and a heat diffusion layer formed of an object having a high thermal conductivity on a part of an inner wall.

A fifth exposure apparatus is the exposure apparatus according to any one of the first to fourth exposure apparatuses, wherein a heat discharging portion for discharging heat from the heat diffusion layer via a heat transfer path or a temperature of the heat diffusion layer is transmitted. Having at least one of a temperature control unit for adjusting via a heat path,
A heat transfer path to the heat-dissipating section or the temperature adjusting section is constituted by an object having a high thermal conductivity, and a heat insulating material is provided on a surface of the object.

A sixth exposure apparatus according to any one of the first to fifth exposure apparatuses, wherein the material constituting the thermal diffusion layer has a higher thermal conductivity in a plane direction than in a thickness direction. It is characterized by being a material.

The device manufacturing method according to the present invention is characterized in that the device is manufactured through a step of performing exposure using any one of the first to sixth exposure apparatuses.

In the construction of the present invention, the heat diffusion layer of the surrounding means prevents a local temperature gradient, and the heat insulating layer reduces or eliminates mutual influence of temperature fluctuations in the space inside and outside the surrounding means. Act like so. For example, when an atmosphere having a heat source or a temperature gradient exists outside the surrounding means, the surrounding means of the conventional exposure apparatus generates an uneven temperature gradient in the surrounding means due to the influence of the heat source position, air conditioning, and the like. However, in such a case, in the present invention, by forming a heat insulating layer on the inner wall of the enclosing means and forming a heat diffusion layer on the outer wall, heat that is diffused or transferred from an external heat source to the heat diffusion layer can be obtained. The heat is diffused over the entire surface of the thermal diffusion layer to generate a uniform temperature gradient.

Therefore, no local heat transfer point is generated inside the surrounding means. In addition, a heat insulating layer between the heat diffusion layer and the inside of the surrounding means shields the accumulated heat of the heat diffusion layer so that the heat is not transferred to the inside of the surrounding means but is radiated or discharged to the outside. As described above, in addition to reducing the occurrence of the local thermal gradient of the enclosing means and the thermal gradient inside the enclosing means, the accumulated heat capacity of the enclosing means increases because the heat is widely diffused to the enclosing means.

When an atmosphere having a heat source and a temperature gradient exists inside the surrounding means, the surrounding means of the conventional exposure apparatus generates an uneven temperature gradient in the surrounding means due to the influence of the position of the heat source, air conditioning and the like. According to the present invention, however, in such a case, by forming a heat insulating layer on the outer wall of the surrounding means and forming a heat diffusion layer on the inner wall of the surrounding means, heat radiated or transferred from the internal heat source to the heat diffusion layer can be obtained. Is diffused over the entire surface of the thermal diffusion layer to generate a uniform temperature gradient. Therefore, no local heat transfer portion is generated outside the surrounding means. In addition, the heat accumulated in the heat diffusion layer is shielded by the heat insulating layer between the heat diffusion layer and the outside of the surrounding means, and the heat is not transferred outside the surrounding means.

In the fifth exposure apparatus, in particular, the accumulated heat in the heat diffusion layer is efficiently exhausted through the object having high thermal conductivity. Therefore, the temperature of the surrounding means does not rise locally, and a uniform temperature distribution is always maintained. further,
The heat-dissipating section can be formed at a location where the performance of the exposure apparatus is not substantially deteriorated, and the heat of the surrounding means can be discharged. At this time, it is possible to form a heat-dissipating portion at a relatively distant place by interposing an object having high thermal conductivity. The heat insulating material on the surface of the object having high thermal conductivity prevents the heat of the object having high thermal conductivity from being transferred to other structures. When the temperature control section is provided, the temperature of the surrounding means can be controlled via an object having high thermal conductivity.

In the sixth exposure apparatus, in particular, heat is diffused over the entire surface of the thermal diffusion layer because the thermal diffusion rate in the plane direction of the thermal diffusion layer is high. On the other hand, since the heat conductivity in the thickness direction is lower than that in the surface direction, heat exchange inside and outside the surrounding means is suppressed and reduced. Further, when the material of the heat diffusion layer is used as the material of the heat transfer path in the fifth exposure apparatus, the heat is efficiently transferred to the heat discharging section or the temperature adjusting section.

As described above, in the exposure apparatus of the present invention, the heat is removed, the temperature is adjusted, the heat is diffused, and the like, depending on the physical properties of the object constituting the surrounding means and the heat transfer path. In comparison, the configuration is easy, and problems such as vibration do not occur.

Therefore, according to the device manufacturing method of the present invention using the exposure apparatus of the present invention, projection exposure with high overlay accuracy is performed.

[0024]

FIG. 1 shows the overall configuration of an exposure apparatus provided with surrounding means according to the present invention. This exposure apparatus applies an image of a circuit pattern area of a reticle 1 to a plurality of shot areas on a semiconductor wafer 3 as a sensitive substrate via a projection lens system 2 by a step-and-repeat method or a step-and-scan method. Exposure. The illumination light for exposure is composed of ultraviolet rays from a mercury discharge lamp (for example, i-line with a wavelength of 365 nm), but also ultraviolet pulse light from an excimer laser light source and ultraviolet light obtained by converting a laser from a YAG laser light source into a harmonic. Etc. can be similarly used. That is, the illumination light is a general term for energy rays such as ultraviolet rays, X-rays, laser light, and electron beams.

The illumination light from the light source 4 passes through a mirror 8 and enters a fly-eye lens system 5 functioning as an optical integrator. The fly-eye lens system 5
On the exit side, a number of secondary light source images are uniformly distributed in a generally square or circular area as a whole. On the exit side of the fly-eye lens system 5, an aperture switching member 6 equipped with a plurality of illumination σ (sigma) apertures for changing the effective shape of the secondary light source image to an annular zone, a small circle, a normal circle, or the like. The aperture switching member 6 is arranged and is driven by a motor 7 so as to be switched to a desired illumination σ aperture. The illumination light transmitted through the illumination σ stop passes through a relay lens system 9 and a mirror 31 and irradiates a masking blade 10 that defines the shape and position of an illumination area on the reticle 1 with a uniform illuminance distribution.

The masking blade 10 is set so as to have an opening similar in shape to the circuit pattern area on the reticle 1 in the case of step-and-repeat exposure.
In the case of the exposure of the step-and-scan method, it is set so as to have a slit-like or rectangular opening crossing the center of the circular visual field of the projection lens system 2. The illumination light transmitted through the opening of the masking blade 10 irradiates the circuit pattern area of the reticle 1 with a uniform intensity distribution via the collimator lens system 11.

The reticle 1 is held on a reticle stage 12 that can move in the X, Y, and θ directions, and is moved by a reticle stage drive system 13. On the back surface of the reticle 1, a pattern to be projected on the wafer 3 is formed. Illumination light for irradiating the reticle 1 passes through the reticle 1 and reaches the surface of the wafer 3 placed on the wafer holder on the XYZ stage 14 via the projection lens system 2. In this way, the image of the circuit pattern of the reticle 1 is projected onto the wafer 3 via the projection lens system 2 at a predetermined projection magnification and transferred. The XYZ stage 14 is moved by an XYZ stage drive system 15, and its X, Y position and rotation (θ) position are sequentially measured by a laser interferometer system 16 using a moving mirror installed on the XYZ stage 14. .

Further, the exposure apparatus of this embodiment includes a reticle alignment system 17 for detecting a reticle alignment mark formed on the periphery of the reticle 1 from above the reticle 1 under illumination light for exposure, A TTL wafer alignment system 18 of a through-the-lens type for detecting a mark attached to the upper shot area only through the projection lens system 2 under non-photosensitive illumination light, and a projection lens system 2
And an off-axis OFA wafer alignment system 19 for detecting various marks on the wafer 3 with non-photosensitive broadband wavelength light.

The entire exposure apparatus is arranged in a chamber 20, and the air circulating in the chamber 20 is air-conditioned at a constant temperature by a main air-conditioner 21. In addition, the heat generating portion in the apparatus or a portion where temperature control is required to be performed with high precision is individually temperature controlled by a method such as partial air conditioning or liquid circulation, and is further surrounded by surrounding means 23. That is, reticle alignment system 17, TTL
Wafer alignment system 18 and OFA wafer alignment system 19 are each surrounded by surrounding means 23. Further, the inside or outside of the surrounding means 23 is air-conditioned by the partial air conditioner 22 or the like.

The optical path of the laser interferometer system 16 for measuring the position of the XYZ stage 14 or the reticle stage 12 is temperature-controlled by a partial air conditioner 22, and at least a part of the optical path is surrounded by surrounding means 23. The light source section including the light source 4 that generates a large amount of heat is also accommodated in the surrounding means 23, and temperature control is performed.

Further, according to the present invention, at least a part of the surrounding means 23 is provided with a heat diffusion layer having a high thermal conductivity for preventing a local temperature gradient, and the effect of temperature fluctuation in the space inside and outside the surrounding means 23 is reduced. Alternatively, it has a heat insulating layer with low thermal conductivity to be erased.

FIG. 2 shows a first embodiment of the surrounding means 23. According to the present invention, the surrounding means reduces heat transfer and radiation caused by heat factors outside the surrounding means to the inside of the surrounding means, and also enables the surrounding means to maintain a uniform temperature gradient. In particular, the surrounding means includes a reticle alignment system 17, a TTL wafer alignment system 18,
It surrounds the FA wafer alignment system 19, the laser interferometer system 16, these optical paths and the like, and is effectively used as a surrounding means that requires high-precision temperature maintenance inside the surroundings.

As shown in FIG. 2, this surrounding means has a heat insulating layer 24 made of an object having a low thermal conductivity on the inner wall, and a heat diffusion layer made of an object having a high thermal conductivity on the outer wall. It has a layer 25. In this configuration, heat from an external heat source is radiated to the heat diffusion layer 25 and transmitted. At this time, in the surrounding means of the conventional exposure apparatus, a non-uniform temperature gradient is generated in the surrounding means due to the influence of the heat source position, air conditioning, etc., but in the surrounding means of the present embodiment, heat is applied to the entire surrounding means. Diffuses and produces a uniform temperature gradient. Therefore, no local heat transfer point is generated inside the surrounding means.

Further, since the heat insulating layer 24 is formed between the heat diffusion layer 25 and the inside of the surrounding means, the heat accumulated in the heat diffusion layer 25 is blocked by the heat insulating layer 24 and is not transferred to the inside of the surrounding means. The heat can be dissipated or discharged to the outside.

As a material of the thermal diffusion layer 25 having a high thermal conductivity, a thermal conductivity of 200 to 1000 Kcal / m · h
A graphite sheet at r ° C. is suitable. For example, a graphite sheet disclosed in JP-A-09-156913 can be used. This material is made of a carbon crystal, and the mosaic spread showing the crystallinity is 0.5 to 20, and is flexible and has good adhesion to others.

The thermal conductivity differs between the thickness direction and the plane direction, and the plane direction is better by about two digits in the thickness direction. Specifically, the thermal conductivity in the plane direction is 600 to 800 W / mk, and the thermal conductivity in the thickness direction is 5 W / mk. As a result, heat can be efficiently released in the plane direction. Therefore, the thermal diffusivity (diffusion rate) is high. Specifically, it is about 765 mm ² / s. Compared to other materials, copper has a thermal conductivity of 2
Twice that of aluminum, and the thermal diffusivity is seven times or more that of copper or aluminum. The specific gravity is 0.3 to 2.6.
It is. As a material of the heat diffusion layer 25, a heat conductive silicone sheet may be selected.

The material of the thermal diffusion layer 25 is not limited to the above-mentioned objects, and various objects having a high thermal conductivity can be used without departing from the gist of the present invention. Similarly, various heat insulating materials can be adopted for the object used for the heat insulating layer 24 without departing from the gist of the present invention.

By constituting the surrounding means 23 with the above-mentioned object, the local thermal gradient of the surrounding means is absorbed with high efficiency, and the heat is quickly transferred to the surrounding means by the high thermal conductivity of the heat diffusion layer 25. In order to efficiently and uniformly transmit the heat to the entire region, it is possible to make the surface of the thermal diffusion layer 25 have a uniform temperature distribution.

Further, since the heat diffusion layer 25 is made of the above-mentioned material having a particularly high thermal conductivity in the plane direction, even if the surrounding means is laid on the surface of a wedge-shaped portion, a circular tube portion or other various shapes. , Can sufficiently diffuse heat. Therefore, it is possible to maintain a uniform temperature distribution even inside the surrounding means, so that it is possible to reduce a decrease in alignment accuracy caused by air fluctuations and the like.

The above-mentioned graphite sheet constituting the thermal diffusion layer 25 can be manufactured into a sheet having a thickness of 20 to 1000 μm. Therefore, even if this graphite sheet is formed on at least a part of the surface of the conventional surrounding means, the effects of the present invention can be sufficiently enjoyed.

The exposure apparatus shown in FIG. 1 further includes a heat discharging section 26 for removing heat from the heat diffusion layer 25 of the surrounding means 23 via the heat transfer path 27. The heat transfer path 27 is made of an object having a high thermal conductivity such as a graphite sheet.

The heat transfer path 27 is covered with a heat insulating material in order to prevent the heat transfer path 27 from contacting another structure and transferring heat. It is also effective to provide a heat insulating material on the surface of the object where heat propagation is particularly concerned around the heat transfer path 27. With this configuration, the heat transferred to the heat diffusion layer 25 can be efficiently transferred to the heat removal unit 26.

Further, the heat discharging section 26 can be replaced with a temperature adjusting section 30 for adjusting the temperature of the thermal diffusion layer 25. According to this configuration, the temperature of the surrounding means 23 can be easily controlled or cooled via the heat transfer path 27.
As a result, the local thermal gradient in the surrounding means 23 can be eliminated in real time, the temperature of the surrounding means 23 can be kept constant, and the inside of the surrounding means 23 can be maintained at a uniform and constant temperature gradient. The temperature adjusting section 30 has a sufficiently large volume as compared with the heat diffusion layer 25 and the heat transfer path 27. As a result, the temperature adjusting section 30 has a larger heat capacity than the heat diffusion layer 25 and the heat transfer path 26, and the heat transferred to the surrounding means 23 is uniformly distributed without substantially increasing the temperature of the temperature adjusting section 30. Can be transmitted to the temperature adjustment unit 30. The structure of the temperature adjustment unit 30 may be an air cooling system or a water cooling system. If a control unit for controlling the characteristics of the temperature adjustment unit 30 is provided in the temperature adjustment unit 30,
It is possible to control the temperature of the surrounding means 23.

FIG. 3 is a schematic view showing a second embodiment of the surrounding means 23. This surrounding means reduces heat transfer and radiation from the heat factor inside the surrounding to the outside of the surrounding, and enables the surrounding means to maintain a uniform temperature gradient. In particular, this surrounding means is effective when it surrounds the light source 4, the motor 7 and the like in the exposure apparatus of FIG. 1 and is used as a surrounding means requiring a highly accurate heat insulating action.

As shown in FIG. 3, the surrounding means has a heat insulating layer 24 made of an object having a low heat conductivity on the outer wall, and a heat diffusion layer made of an object having a high heat conductivity on the inner wall. It has a layer 25. As the thermal diffusion layer 25,
It is preferable to use a graphite sheet or the like disclosed in JP-A-9-156913.

In this configuration, heat from the heat source inside the surrounding means is radiated or transmitted to the heat diffusion layer 25. At this time, in the surrounding means of the conventional exposure apparatus, a non-uniform temperature gradient was generated in the surrounding means due to a heat source position or the like.
In the surrounding means of this embodiment, heat is diffused over the entire surface of the thermal diffusion layer 25 to generate a uniform temperature gradient. Therefore, no local heat transfer portion is generated inside the surrounding means. Therefore, the amount of stored heat can be increased as compared with the conventional surrounding means. Further, since the heat insulating layer 24 is formed between the heat diffusion layer 25 and the outside of the surrounding means, the heat accumulated in the heat diffusion layer 25 is shielded by the heat insulating layer 24 and is not transmitted to the outside of the surrounding means. Heat can be stored inside, and the heat can be efficiently exhausted by the exhaust means or the exhaust heat means.

The heat diffusion layer 25 is connected to a heat discharge section 26 by a heat transfer path 27. The heat transfer path 27 is made of an object having a high thermal conductivity such as a graphite sheet.
The heat transfer path 27 is covered with a heat insulating material to prevent the heat transfer path 27 from contacting another structure and transferring heat.
It is also effective to provide a heat insulating material on the surface of the object where heat propagation is particularly concerned around the heat transfer path 27.

FIG. 4 is a schematic view showing a third embodiment of the surrounding means 23. This surrounding means sandwiches both sides of the heat diffusion layer 25 with the heat insulating layer 24 to prevent heat exchange inside and outside the surrounding means,
Or it has a structure to reduce it. In particular, the present invention is effective when used as a surrounding means such as an optical path cover, which needs to prevent heat exchange with high precision inside and outside the surrounding means.

In this configuration, the heat inside or outside the surrounding means is substantially shielded by the heat insulating layers 24 on both surfaces. Further, the heat not blocked by the heat insulating layer 24 is transferred to the heat diffusion layer 25.
As a result, the thermal diffusion layer 25 is diffused over the entire surface. This prevents a local thermal gradient from occurring and prevents a local temperature rise. Further, the heat diffusion layer 25 is connected to the heat exhaust portion 26 by the heat transfer path 27. The heat transfer path 27 is covered with a heat insulating material to prevent heat from being transferred in contact with another structure. Therefore, the heat accumulated in the thermal diffusion layer 25 can be efficiently exhausted.

The surrounding means of this embodiment has a structure in which both surfaces of the heat insulating layer 24 are sandwiched between the heat diffusion layers 25 to prevent or reduce heat exchange between the inside and outside of the surrounding means. Thus, a local thermal gradient can be prevented, and a uniform temperature distribution can be obtained over the entire inner wall and the outer wall. By this action, when heat is transferred to the heat insulating layer 24, no local heat transfer portion is generated, so that the heat insulating effect can be improved.

As shown in FIG. 5, without using the heat insulating layer 24, the conventional enclosing means 53 is provided with a heat diffusion layer 25 made of a graphite sheet having a high thermal conductivity or an object having a high thermal conductivity.
And by providing a uniform temperature distribution over the entire surface of the surrounding means 53, it is possible to sufficiently obtain effects such as improvement of the measurement reproducibility accuracy of the alignment optical system. Further, if a plurality of heat diffusion layers and heat insulation layers are alternately formed, the effects of the present invention can be more enjoyed.

[Embodiment of Device Manufacturing Method] Next, an embodiment of a device manufacturing method using the above-described projection exposure apparatus will be described. FIG. 6 shows a semiconductor device (IC or LSI)
2 shows a flow of manufacturing a semiconductor chip such as a liquid crystal panel or a CCD. In step 1 (circuit design), the circuit of the semiconductor device is designed. Step 2 (mask production)
Then, a mask on which the designed circuit pattern is formed is manufactured. On the other hand, in step 3 (wafer manufacturing), a wafer is manufactured using a material such as silicon. Step 4 (wafer process) is called a pre-process, and an actual circuit is formed on the wafer by lithography using the prepared mask and wafer. The next step 5 (assembly) is called a post-process, and is a process of forming a semiconductor chip using the wafer produced in step 4, and includes processes such as an assembly process (dicing and bonding) and a packaging process (chip encapsulation). including. In step 6 (inspection), an operation confirmation test of the semiconductor device manufactured in step 5 is performed.
An inspection such as a durability test is performed. Through these steps, a semiconductor device is completed and shipped (step 7).

FIG. 7 shows the wafer process (step 4).
The detailed flow of is shown. Step 11 (oxidation) oxidizes the wafer's surface. Step 12 (CVD) forms an insulating film on the wafer surface. Step 13 (electrode formation) forms electrodes on the wafer by vapor deposition. In step 14 (ion implantation), ions are implanted into the wafer. In step 15 (resist processing), a photosensitive agent is applied to the wafer. Step 16 (exposure) uses the above-described exposure apparatus to print and expose the circuit pattern of the mask onto the wafer. Step 17 (development) develops the exposed wafer. In step 18 (etching), portions other than the developed resist image are removed. In step 19 (resist stripping), unnecessary resist after etching is removed. By repeating these steps, multiple circuit patterns are formed on the wafer.

By using the manufacturing method of this embodiment, it is possible to manufacture a highly integrated semiconductor device which has conventionally been difficult to manufacture.

[0055]

As described above, according to the present invention,
The surrounding means can have a substantially uniform temperature distribution by the heat diffusion layer. Therefore, local heat accumulation can be prevented. Therefore, the accumulated heat capacity of the surrounding means can be increased as compared with the related art.

Further, by providing the heat-dissipating section and configuring the heat transfer path with an object having a high thermal conductivity, the heat accumulated in the surrounding means can be efficiently discharged. In addition, by providing the temperature adjusting section and configuring the heat transfer path with an object having high thermal conductivity, the temperature of the surrounding means can be efficiently adjusted in real time.

Further, by providing a heat-dissipating section and a temperature-adjusting section and forming the heat transfer path with an object having a high thermal conductivity, the heat of the surrounding means can be discharged away from the surrounding means. Therefore, it is possible to reduce the influence of the heat of the heat-dissipating portion and the like on the portion that is sensitive to the surrounding means and the heat factor.

Further, by stacking the heat diffusion layer and the heat insulating layer, it is possible to reduce or prevent the accumulated heat of the heat diffusion layer from passing through the surrounding means in the thickness direction and conducting the heat. In particular, it is more effective to use a graphite sheet whose thermal conductivity in the plane direction is two orders of magnitude different from that in the thickness direction for the object constituting the heat diffusion layer.

Further, since the local thermal gradient of the surrounding means can be eliminated in real time, the temperature gradient of the surrounding means can be made uniform, and the temperature fluctuation can be reduced, so that the heat transfer inside and outside the surrounding means can be reduced. Further, by surrounding the optical path of the optical system with the surrounding means, it is possible to reduce the fluctuation of air on the optical path. Therefore, the performance of the exposure apparatus can be improved.

Further, since the temperature is adjusted without adjusting the temperature by the fluid which is a factor of the vibration, the problem of the influence of the vibration when the fluid is used does not occur and the configuration is easy.

Further, since the temperature is adjusted only by the characteristics of the material constituting the surrounding means and the like, the printing performance and alignment performance of the exposure apparatus can be improved without impairing the throughput of the exposure apparatus.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall configuration of an exposure apparatus provided with surrounding means according to the present invention.

FIG. 2 is a diagram showing a first embodiment of a surrounding means in the apparatus of FIG. 1;

FIG. 3 shows a second embodiment of the surrounding means in the device of FIG. 1;

FIG. 4 shows a third embodiment of the surrounding means in the device of FIG. 1;

FIG. 5 shows a fourth embodiment of the surrounding means in the device of FIG. 1;

FIG. 6 is a flowchart of a method for manufacturing a semiconductor device that can use the exposure apparatus of the present invention.

FIG. 7 is a flowchart showing a detailed flow of a wafer process in FIG. 6;

[Explanation of symbols]

1: reticle, 2: projection lens system, 3: semiconductor wafer,
4: light source, 5: fly-eye lens system, 6: aperture switching member, 7: motor, 8: mirror, 9: relay lens system, 1
0: masking blade, 11: collimator lens system,
12: reticle stage, 13: reticle stage drive system, 14: XYZ stage, 15: XYZ stage drive system, 16: laser interferometer system, 17: reticle alignment system, 18: TTL wafer alignment system, 1
9: OFA wafer alignment system, 20: chamber, 2
1: Main air conditioner, 22: Partial air conditioner, 23: Surrounding means, 24: Heat insulation layer, 25: Heat diffusion layer, 26: Heat exhaust portion, 2
7: heat transfer path, 30: temperature controller, 31: mirror, 5
3: Conventional surrounding means.

Claims (7)

[Claims] 1. An exposure apparatus for exposing a pattern of an original onto a substrate via a projection optical system, comprising: an enclosing means for enclosing at least a part of the apparatus, the enclosing means having at least a part having a low thermal conductivity. An exposure apparatus comprising: a heat insulating layer formed by an object having a thermal conductivity; and a heat diffusion layer formed by an object having a high thermal conductivity. An enclosing unit configured to detect a position of the original plate, the substrate, a stage that moves while holding the original plate, or a position of a stage that moves while holding the substrate; The exposure apparatus according to claim 1, wherein the exposure apparatus surrounds at least a part of a system optical path, a light source for exposure, or a heat source of the exposure apparatus. 3. When the surrounding means surrounds at least a part of the optical path of the position detecting means or the optical system, the surrounding means is constituted by an object having a low thermal conductivity on a part of an inner wall. The exposure apparatus according to claim 2, further comprising a heat diffusion layer formed of an object having a high thermal conductivity on a part of an outer wall, the heat diffusion layer having a heat insulating layer formed thereon. 4. When the surrounding means surrounds at least a part of the light source or the heat source for exposure, the surrounding means is formed of an object having low thermal conductivity on a part of an outer wall. The exposure apparatus according to claim 2, further comprising: a heat diffusion layer having a heat insulating layer and a part having a high thermal conductivity on an inner wall. 5. The apparatus according to claim 1, further comprising at least one of a heat-dissipating unit that exhausts heat from the heat-diffusion layer through a heat-transfer path and a temperature-adjusting unit that adjusts the temperature of the heat-diffusion layer through a heat-transfer path. The heat transfer path to the heat-dissipating section or the temperature adjusting section is constituted by an object having a high thermal conductivity, and a heat insulating material is provided on a surface of the object. Exposure equipment. 6. The material according to claim 1, wherein the material constituting the heat diffusion layer has a higher thermal conductivity in a plane direction than in a thickness direction. 3. The exposure apparatus according to claim 1. 7. A device manufacturing method, wherein a device is manufactured through a step of performing exposure using the exposure apparatus according to claim 1.