JP2016095412A - Exposure equipment, and manufacturing method of article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide exposure equipment capable of reducing astigmatism and advantageous for stabilizing optical characteristics.SOLUTION: Exposure equipment 100 exposes, through a projection optical system 60, a pattern of an original plate 20 on a base plate 30. The exposure equipment 100 includes: gas supply means 84, etc. configured to supply a gas to an optical element 65, etc. arranged in vicinity of a pupil position of the projection optical system 60; and control means 90 configured to control the gas supply means 84. Here, the control means 90 controls the gas supply means 90 so that a direction of a gas supply is changed according to temperature distribution of the optical element 65, etc. caused by irradiation of exposure light.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an exposure apparatus and a method for manufacturing an article.

  In a lithography process included in a process of manufacturing a liquid crystal display device or the like as an article, the exposure apparatus applies a pattern of an original (such as a mask) to a photosensitive substrate (a resist layer is formed on the surface) via a projection optical system. This is a device for transferring to a glass plate or the like. Among these, Patent Document 1 is a catadioptric type in which the projection optical system includes a meniscus lens (aspheric lens) that is a refractive optical member between the concave mirror and the convex mirror in order to further improve the optical performance. An exposure apparatus is disclosed. On the other hand, from the viewpoint of exposure image formation characteristics, the optical characteristics are deteriorated due to the surrounding environment, and the focus difference or astigmatism (astigmatism) that can be caused by the members in the projection optical system absorbing the exposure light. It is desirable to reduce such aberrations. Therefore, Patent Document 2 discloses a gas whose temperature is adjusted in a lens barrel that accommodates the projection optical system in accordance with the temperature increase in the entire projection optical system caused by the exposure light being absorbed by the members in the projection optical system. Discloses an exposure apparatus that reduces the temperature distribution change in the projection optical system.

JP 2008-89832 A Japanese Patent No. 5517847

  Here, particularly in an exposure apparatus including a catadioptric projection optical system, the energy of exposure light is concentrated on a meniscus lens installed in the vicinity of the pupil of the projection optical system. Then, the meniscus lens absorbs a part of the energy of the exposure light, and the temperature distribution is generated in the inside, thereby changing the refractive index distribution and the surface shape. As a result, the optical characteristics of the projection optical system (mainly vertical and horizontal asperities or It can degrade diagonally asphalt). In order to reduce such deterioration, if the technique disclosed in Patent Document 2 is applied, gas is always allowed to flow in a fixed direction from the same air supply port toward the meniscus lens.

  However, depending on the lithography process, the original plate is frequently changed (for example, once every 28 sheets / lot). On the other hand, the pattern of the original plate is formed by vertical lines, horizontal lines, or diagonal lines, and when irradiated with exposure light, diffracted light is generated in accordance with the direction of the lines forming the pattern. In addition, the direction of the line forming the pattern is different in each original plate. This is because each time the original is exchanged, the direction in which light is diffracted during exposure is different, and the position where the exposure light energy is absorbed in the meniscus lens also changes. The temperature distribution will also change. Therefore, if the gas is always supplied from the same air supply port in a fixed direction as described above, the temperature distribution changes greatly depending on the orientation of the line forming the pattern, which adversely affects the optical characteristics. There may be cases.

  The present invention has been made in view of such a situation, and an object of the present invention is to provide an exposure apparatus that reduces astigmatism and is advantageous for stabilizing optical characteristics, for example.

  In order to solve the above problems, the present invention is an exposure apparatus that exposes a pattern of an original on a substrate via a projection optical system, and an optical element disposed in the vicinity of the pupil position of the projection optical system, A gas supply unit configured to supply a gas; and a control unit configured to control the gas supply unit. The control unit is configured to change a gas supply direction according to a temperature distribution of the optical element generated by exposure light exposure. Further, the gas supply means is controlled.

  According to the present invention, for example, it is possible to provide an exposure apparatus that reduces astigmatism and is advantageous in stabilizing optical characteristics.

It is a figure which shows the structure of the exposure apparatus which concerns on one Embodiment of this invention. It is a figure which shows arrangement | positioning of a 2nd air inlet and a 2nd exhaust port. It is a block diagram which shows the structure of a switching control part. It is a figure which shows the temperature distribution of the space between a convex-surface mirror and a meniscus lens. It is a figure explaining the 1st example which switches the air supply direction of a 2nd air supply mechanism. It is a figure explaining the 2nd example which switches the air supply direction of a 2nd air supply mechanism. It is a figure which shows the structure of the air supply mechanism in case this invention is not applied. It is a figure which shows the air supply state at the time of using the air supply mechanism shown in FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  First, the configuration of an exposure apparatus according to an embodiment of the present invention will be described. FIG. 1 is a schematic diagram showing a configuration of an exposure apparatus 100 according to the present embodiment. The exposure apparatus 100 can be used, for example, in a lithography process in a manufacturing process of a flat panel such as a liquid crystal display device or an organic EL device. Particularly in the present embodiment, the exposure apparatus 100 includes a scanning projection exposure apparatus that transfers (exposes) an image of a pattern formed on the mask 20 onto the plate 30 (on the substrate) by a step-and-scan method. To do. The exposure apparatus 100 includes an illumination optical system 43, a mask stage 21, a projection optical system 60, a plate stage 33, and a control unit 88. 1 and the following drawings, the Y axis is taken in the scanning direction of the mask 20 and the plate 30 at the time of exposure in a plane perpendicular to the Z axis that is the vertical direction, and the X axis is taken in the non-scanning direction orthogonal to the Y axis. Is taking. The plate 30 is a substrate to be processed made of, for example, a glass material and having a surface coated with a photosensitive agent (resist). Further, the mask 20 is an original plate made of, for example, a glass material, on which a pattern (a fine uneven pattern) to be transferred to the plate 30 is formed.

  The illumination optical system 43 illuminates the mask 20 held on the mask stage 21 using the light flux from the light source 42. As the light source 42, for example, an Hg lamp can be used, but a part of the output wavelength of the Hg lamp such as i-line, h-line, and g-line may be used. Further, the illumination optical system 43 can switch to an appropriate illumination condition according to the condition of the pattern formed on the mask 20 using the illumination condition switching mechanism 44. The mask stage 21 holds the mask 20 and is movable in the X and Y axis directions, for example.

  The projection optical system 60 employs a mirror projection method composed of a plurality of optical elements, and projects the pattern image from the mask 20 onto the plate 30 held by the plate stage 33. The projection optical system 60 includes a flat plate transmissive element 66, a flat mirror 67, a concave mirror 68, a convex mirror 69, and a meniscus lens 65. The flat plate-type transmissive element 66 is a transmissive optical element that is disposed at two locations on the incident side and the exit side of the projection optical system 60 and is used to supplementarily improve the imaging performance of the projection optical system 60. The material of the flat transmissive element 66 may be, for example, a glass material that has substantially no internal absorption with respect to exposure light. Each of the plane mirror 67, the concave mirror 68, and the convex mirror 69 is a member that reflects a pattern image, and the material thereof may be a glass material having a small linear expansion coefficient. The meniscus lens 65 is an aspheric lens as a refractive optical member used for improving optical performance. The material of the meniscus lens 65 may be, for example, a glass material that has substantially no internal absorption with respect to exposure light. The convex mirror 69 and the meniscus lens 65 are optical elements installed near the pupil position of the projection optical system 60. Further, the meniscus lens 65 is desirably installed in terms of improving the optical performance, but it is not always necessary to install the meniscus lens 65 when, for example, the required exposure accuracy is low. Here, assuming that the projection magnification of the projection optical system 60 is the same magnification, the exposure apparatus 100 performs scanning exposure while moving the mask 20 and the plate 30 synchronously, thereby obtaining an image of the pattern formed on the mask 20. It can be transferred onto the plate 30 coated with a photosensitive agent. Each element constituting the projection optical system 60 is accommodated in the lens barrel 61.

  Further, the exposure apparatus 100 includes at least two types of air supply mechanisms (a first air supply mechanism and a second air supply mechanism) as gas supply means for supplying gas into the lens barrel 61. First, the first air supply mechanism supplies a gas whose temperature is adjusted by a temperature adjusting device (not shown) in order to stabilize the temperature in the lens barrel 61. The first air supply mechanism is installed in the lower wall portion on the exposure light emission side of the lens barrel 61, and has a first air supply port 72 for supplying air into the lens barrel 61, and an upper surface of the lens barrel 61 on the exposure light incident side. And a first exhaust port 73 that is installed on the wall and exhausts to the outside of the lens barrel 61. Both the first air supply port 72 and the first exhaust port 73 are connected to the temperature adjusting device via a pipe. The temperature adjusting device can maintain the inside of the lens barrel 61 at a certain desired temperature by controlling the temperature of the gas supplied based on an instruction from the control unit 88.

  On the other hand, the second air supply mechanism has a second air supply port 85 that can supply gas toward a space sandwiched between the convex mirror 69 and the meniscus lens 65, that is, in contact with these lenses. Further, the second air supply mechanism has a second exhaust port 86 that can exhaust the gas supplied from the second air supply port 85 to the outside of the lens barrel 61.

  FIG. 2 is a schematic plan view showing the arrangement of the second air supply port 85 and the second air exhaust port 86 when the convex mirror 69 side is viewed from the concave mirror 68 side along the optical axis 62 of the projection optical system 60. is there. Here, an area 63 indicated by an octagon in the drawing schematically shows a plane (YZ plane) area orthogonal to the optical axis 62 in a space between the convex mirror 69 and the meniscus lens 65. There are a plurality of the second air supply ports 85 and the second air exhaust ports 86, and one air supply port 85 and one air exhaust port 86 are respectively in a plane including the region 63 with the optical axis 62 as a reference. They are arranged symmetrically. In the present embodiment, the second air supply mechanism includes four second air supply ports 85a to 85d and four second air exhaust ports 86a to 86d as an example, and each of them has an angle of 45 degrees around the optical axis 62. It is assumed that they are arranged at intervals. For example, the second air supply port 85a supplies air toward the second exhaust port 86a, and the second exhaust port 86a is disposed so as to exhaust the gas supplied from the second air supply port 85a. The same is true for the arrangement of the other second air supply ports 85b to 85d and the second exhaust ports 86b to 86d.

  According to such a configuration, the air supply direction (the direction in which gas is supplied) enabled by the second air supply mechanism is not limited to one direction in the plane including the region 63, and a plurality of directions (this embodiment). Then there are four directions). Further, in the configuration shown in FIG. 2, among the arrangement of the second air supply port 85 and the second exhaust port 86, the four second air supply ports 85 a to 85 d are arranged below the optical axis 62 and corresponding thereto The four second exhaust ports 86 a to 86 d are arranged above the optical axis 62. However, conversely, the second air supply port 85 and the second exhaust port 86 may be arranged on the upside down side. Or it is good also as a supply / exhaust port, without distinguishing an air supply port and an exhaust port. In the configuration shown in FIG. 2, the supply direction is configured to be four directions. However, the second supply port 85 and the second exhaust port 86 may be configured so that at least two supply directions are established. That's fine. Furthermore, the second air supply mechanism may be configured with only the second air supply port 85 without providing the second exhaust port 86.

  Here, it is assumed that a convex mirror 69 and a meniscus lens 65 are installed in the vicinity of the pupil of the projection optical system 60. On the other hand, for example, when the projection optical system 60 does not have the meniscus lens 65, the second air supply port 85 is not in the space between the convex mirror 69 and the meniscus lens 65 but in the convex mirror 69. The air is supplied toward or in contact with the convex mirror 69.

  Further, the second air supply port 85 and the second exhaust port 86 are each connected to a temperature adjusting device 81 as temperature adjusting means via a pipe. The temperature adjustment device 81 controls the temperature of the gas supplied based on an instruction from the control unit 88. Further, the second air supply mechanism is a switching mechanism 84 installed between the temperature adjusting device 81, the second air supply port 85, and the second exhaust port 86, and a control unit that controls switching by the switching mechanism 84. Switching control unit 90. In addition, the switching control unit 90 acquires exposure information from the control unit 88 and uses the second supply port 85a to 85d and the second exhaust port 86a to 86d based on the exposure information. The air supply port 85 and the second exhaust port 86 are selected, and a switching instruction is transmitted to the switching mechanism 84. The switching mechanism 84 is a switching unit that can switch between the second supply port 85 and the second exhaust port 86 to be used based on the switching instruction received from the switching control unit 90.

  FIG. 3 is a block diagram illustrating a detailed configuration of the switching control unit 90. The switching control unit 90 includes a switching location determination unit 91, a switching execution determination unit 95, and an information holding unit 92. The switching location determination unit 91 determines the second air supply port 85 and the second exhaust port 86 (switching location information) to be used based on the mask information acquired from the control unit 88. The switching execution determination unit 95 transmits a timing signal for executing switching to the information holding unit 92 based on the device state signal acquired from the control unit 88. The information holding unit 92 holds the switching point information to the switching mechanism 84 while holding the switching point information based on the switching point information acquired from the switching point determination unit 91 and the timing signal acquired from the switching execution determination unit 95. Send.

  The plate stage 33 is installed on the main body surface plate 31, holds the plate 30 via the check 32, and is movable in, for example, six directions of X, Y, Z, ωx, ωy, and ωz. At the time of exposure, the mask 20 held on the mask stage 21 and the plate 30 held on the plate stage 33 are conjugated with each other via the projection optical system 60 (the object plane and the image plane of the projection optical system 60). ).

  The control unit 88 is configured by, for example, a computer and is connected to each component of the exposure apparatus 100 via a line, and can control operation and adjustment of each component according to a program or the like. In particular, in the present embodiment, the control unit 88 can manage information (mask information) about the mask 20 to be used and the apparatus state signal as exposure information, and can appropriately transmit the information to the switching control unit 90. In the present embodiment, as an example of the control means for controlling the operation of the second air supply mechanism, the switching control unit 90 is provided separately from the control unit 88. However, the switching control unit 90 is included in the control unit 88. It is good also as what is constituted and control part 88 controls operation of the 2nd air supply mechanism. Further, the controller 88 may be configured integrally with other parts of the exposure apparatus 100 (in a common casing), or separate from the other parts of the exposure apparatus 100 (in a separate casing). It may be configured.

  The exposure apparatus 100 includes a laser interference length measuring device 50, a first measurement mechanism 40, and a second measurement mechanism 41. The laser interference length measuring device 50 measures the positions of the mask stage 21 and the plate stage 33. The laser interferometer 50 includes, for example, a laser head 51, two interferometer mirrors 52 and 53, a first reflection mirror 54 attached to the plate stage 33, and a second reflection mirror 55 attached to the mask stage 21. including. The first measurement mechanism 40 is disposed above the mask stage 21 and measures the overlapping position of the mask 20 and the plate 30 via the projection optical system 60. The second measurement mechanism 41 is disposed above the plate stage 33 and measures the focus position between the mask 20 and the plate 30 via the projection optical system 60. Here, when the illumination optical system 43 illuminates the mask 20, the first measurement mechanism 40 is configured to be movable so that the illumination light is not blocked by the first measurement mechanism 40. It has a system and can be withdrawn from the illumination beam as appropriate. Each component described above is housed inside the chamber 10.

  Next, regarding temperature control inside the lens barrel 61 in the present embodiment, temperature control (supply of temperature-controlled gas) in a space sandwiched between the convex mirror 69 and the meniscus lens 65 will be described. At the time of exposure, the meniscus lens 65 or the convex mirror 69 installed in the vicinity of the pupil of the projection optical system 60 has the advantage of suppressing deterioration of the optical characteristics (mainly focus difference or astigmatism) of the projection optical system 60. In these lenses, it is desirable that the temperature is approximately uniform. However, as described above, when the meniscus lens 65 absorbs a part of the energy of the exposure light and changes in the temperature distribution occur in the inside thereof, the refractive index distribution and the surface shape change, the optical characteristics of the projection optical system 60 are changed. Can deteriorate. The same applies to the convex mirror 69 adjacent to the meniscus lens 65 in the optical axis direction. Even when a glass material having a small linear expansion coefficient is used, the mirror surface shape changes due to absorption of exposure light by the mirror film. In addition, the optical characteristics of the projection optical system 60 can be deteriorated.

  Here, in order to clarify the characteristics of the exposure apparatus 100 according to the present embodiment, as a reference, a countermeasure in the exposure apparatus that does not apply the present invention to the possibility of deterioration of the optical characteristics of the projection optical system 60 as described above. explain. The pattern formed on the mask 20 is a line pattern drawn with vertical lines, horizontal lines, or diagonal lines. When this pattern is irradiated with light, the exposure light is diffracted in accordance with the direction of the line forming the pattern, and roughly at the position of the meniscus lens 65 around the optical axis 62, for example, Appears as diffraction of light in a 0, 90, 45 or 135 degree orientation. The position where the exposure light is absorbed by the meniscus lens 65 varies depending on the direction in which such light is diffracted.

  FIG. 4 is a schematic plan view showing the temperature distribution 64 in the meniscus lens 65. Among these, FIG. 4A shows a temperature distribution when light is diffracted by a pattern mainly formed by horizontal lines, and FIG. 4B shows a light distribution by a pattern mainly formed by vertical lines. Shows the temperature distribution when is diffracted. In the figure, an area 63 indicated by an octagon is the same as the area 63 shown in FIG. As shown in FIG. 4A, the temperature distribution 64 generated when light is diffracted mainly in a pattern formed by horizontal lines extends so that the angle extends 90 degrees, that is, along the Z-axis direction (see FIG. 4A). Temperature rises). On the other hand, the temperature distribution 64 generated when light is diffracted mainly in a pattern formed by vertical lines has an angle of 0 degrees, that is, extends along the Y-axis direction, as shown in FIG. 4B. To spread.

  FIG. 7 shows a configuration of an air supply mechanism that can supply gas toward a space between the convex mirror 69 and the meniscus lens 65 in the exposure apparatus 100 according to this embodiment, which can be considered in an exposure apparatus to which the present invention is not applied. It is a schematic plan view which shows. In the figure, the same parts as those used in the description of the exposure apparatus 100 are denoted by the same reference numerals, and the description thereof is omitted. In an exposure apparatus to which the present invention is not applied, there is no air supply mechanism that supplies gas mainly in the space between the convex mirror 69 and the meniscus lens 65, or even if it exists, as shown in FIG. An air supply port 82 and one exhaust port 83 are arranged, and the air supply direction is always constant. In the case where there is no air supply mechanism that supplies gas mainly in the space between the convex mirror 69 and the meniscus lens 65, for example, as in the first air supply mechanism in the present embodiment, the lens barrel 61 is used. A part of the gas that controls the temperature of the entire interior of the gas passes only through the space.

  FIG. 8 is a schematic plan view showing an air supply state (cooling state) when the air supply mechanism as shown in FIG. 7 is used for the temperature distribution as shown in FIG. Among these, Fig.8 (a) has shown the air supply state in case the temperature distribution 64 in the meniscus lens 65 is as shown to Fig.4 (a). On the other hand, FIG. 8B shows an air supply state when the temperature distribution 64 is as shown in FIG. First, in the case of the temperature distribution as shown in FIG. 4A, the temperature rises because the temperature distribution matches the supply direction from the supply port 82 to the exhaust port 83 as shown in FIG. 8A. The whole portion to be cooled can be efficiently cooled, and the temperature distribution change can be reduced. However, in the case of the temperature distribution as shown in FIG. 4B, the supply direction from the supply port 82 to the exhaust port 83 does not change as shown in FIG. Since only the gas passes, only a part of the temperature rising portion can be cooled. Therefore, it is difficult to reduce the change in the temperature distribution, and not only that, but the change in the temperature distribution becomes conversely large, which may further deteriorate the optical characteristics.

  On the other hand, individual optical characteristics of focus difference or astigmatism (vertical / horizontal astigmatism or oblique astigmatism) will be considered. First, the focus difference can be corrected by measuring the focus change using the second measurement mechanism 41 and moving the plate stage 33 based on the measurement result. However, astigmatism cannot be corrected by moving the plate stage 33.

  Therefore, in the present embodiment, for the space sandwiched between the convex mirror 69 and the meniscus lens 65, the second air supply mechanism that makes the air supply direction variable according to the predicted temperature distribution is used. Reduce distribution changes.

  FIG. 5 is a schematic plan view illustrating a first example of switching the air supply direction of the second air supply mechanism with respect to the temperature distribution in the meniscus lens 65 in the present embodiment. Here, a case where the projection optical system 60 is continuously irradiated with the exposure light from the mask 20 on which a vertical line pattern is mainly formed will be exemplified. In this case, if the exposure light is simply continuously irradiated, the light is diffracted in the azimuth direction of 0 degrees in the meniscus lens 65 and the temperature in the diffracting direction becomes higher than the surroundings as shown in FIG. It becomes temperature distribution. Therefore, in the present embodiment, the control unit 88 transmits mask information related to the mask 20 used this time that is managed in advance to the switching location determination unit 91 and transmits an apparatus status signal to the switching execution determination unit 95. In particular, in the mask information transmitted here, the orientation of at least one pattern (line pattern) of the patterns formed on the mask 20, for example, information that the pattern is mainly formed by vertical lines. It is included. Next, the switching location determination unit 91 determines switching location information based on the mask information acquired from the control unit 88. At this time, the switching location determination unit 91 predicts from the mask information that the temperature distribution in the meniscus lens 65 becomes a temperature distribution 64 as shown in FIG. And the switching location determination part 91 selects and determines the 2nd air supply port 85d and the 2nd exhaust port 86d as switching location information so that the temperature distribution 64 and an air supply direction may match. On the other hand, the switching execution determination unit 95 transmits a timing signal to the information holding unit 92 based on the device state signal acquired from the control unit 88 as described above. Here, the timing signal is the following apparatus state, that is, after the exposure is completed until the next exposure is started, for example, during mask replacement (several minutes) or periodic maintenance (tens of minutes) It is desirable to be sent to. Next, as described above, the information holding unit 92 performs the switching while holding the switching location information based on the switching location information acquired from the switching location determination unit 91 and the timing signal acquired from the switching execution determination unit 95. The switching location information is transmitted to the mechanism 84. Then, the switching mechanism 84 switches the air supply port and the exhaust port used in the second air supply mechanism to the second air supply port 85d and the second exhaust port 86d at a timing based on the timing signal. As a result, the air supply direction by the second air supply mechanism matches the temperature distribution (shape) in the meniscus lens 65, so that the temperature distribution in the meniscus lens 65 can be more efficiently suppressed and the temperature can be made uniform. Can do.

  FIG. 6 is a schematic plan view illustrating a second example of switching the air supply direction of the second air supply mechanism with respect to the temperature distribution in the meniscus lens 65 in the present embodiment. Here, a case where the projection optical system 60 is continuously irradiated with a plurality of patterns, for example, exposure light from the mask 20 on which two oblique line patterns of 45 degrees and 135 degrees with the optical axis 62 as the center are formed. Illustrate. In this case, the switching location determination unit 91 selects the second air supply port 85 and the second exhaust port 86 according to the two temperature distributions in the meniscus lens 65, and determines the switching location information, as described above. That's fine. Specifically, in this case, the plurality of air supply ports and exhaust ports determined as the switching location information are a set of the second air supply port 85b and the second air supply port 86b, and the second air supply port 85c. A pair with the second exhaust port 86c. In addition, when there are a plurality of patterns formed on the mask 20 to be used, the switching location determination unit 91 separates from the second air supply port 85 in accordance with the direction in which the temperature distribution extends most. You may determine the 2nd exhaust port 86 as switching location information.

  As described above, the exposure apparatus 100 uses the second air supply mechanism to suppress a change in temperature distribution that can be generated in a meniscus lens or the like that is installed near the pupil of the projection optical system 60 and in which the energy of the exposure light is concentrated. Therefore, the optical characteristics can be stabilized. Furthermore, even if the exposure apparatus 100 replaces the mask 20, for example, the second air supply mechanism switches the air supply direction in consideration of the direction of the line forming the pattern of the mask 20, so that the optical characteristics are particularly important. This is suitable for suppressing deterioration with respect to astigmatism (vertical / horizontal or diagonal).

  As described above, according to this embodiment, it is possible to provide an exposure apparatus that reduces astigmatism and is advantageous for stabilizing optical characteristics.

  In the above description, the switching location determination unit 91 determines the switching location based on the mask information acquired from the control unit 88, but the present invention is not limited to this. For example, in the illumination optical system 43, the illumination condition switching mechanism 44 switches to an appropriate illumination condition according to the mask 20 to be used. Here, the illumination condition refers to each condition such as annular illumination, small σ illumination, or large σ illumination. When the illumination condition changes, the energy of the exposure light incident on the projection optical system 60 and the shape of the exposure light irradiated on the meniscus lens 65 also change. Therefore, astigmatism can also occur due to illumination conditions during exposure. Therefore, the switching location determination unit 91 may determine the switching location in consideration of this illumination condition.

  In this case, the control unit 88 manages the illumination condition as exposure information in addition to the mask information and the apparatus state signal. Furthermore, the control unit 88 also manages information related to changes in optical characteristics (mainly astigmatism) that can be generated by continuously irradiating exposure light under the illumination conditions, which is obtained in advance from actual exposure results. To do. Here, the switching location determination unit 91 determines the switching location information on the mask 20 specified from the mask information acquired from the control unit 88 based on the exposure information acquired from the control unit 88. At this time, the switching location determination unit 91 compares and refers to the information on the change in optical characteristics obtained from the exposure result in advance and the illumination condition to be used, and particularly in the direction in which the change is large among the vertical and horizontal asses or the oblique asses. The switching location information is determined so that the air supply direction matches. Note that information regarding changes in optical characteristics (astigmatism) generated by continuously irradiating exposure light under the illumination conditions to be used may be results obtained by measuring using the second measurement mechanism 41. On the other hand, the switching execution determination unit 95 transmits a timing signal to the information holding unit 92 based on the device state signal as in the above description. At this time, the timing signal is the following apparatus state, that is, between the end of exposure and the start of the next exposure, for example, mask exchange (several minutes), illumination condition change (several minutes), It is desirable to be sent during regular maintenance (tens of minutes). According to this, for example, even when the exposure energy irradiated to the projection optical system 60 changes in addition to the change of the mask 20, the same effects as described above are preferably obtained.

(Product manufacturing method)
The method for manufacturing an article according to an embodiment of the present invention is suitable for manufacturing an article such as a micro device such as a liquid crystal display device or an element having a fine structure. In the method for manufacturing an article according to the present embodiment, a latent image pattern is formed on the photosensitive agent applied to the substrate using the above exposure apparatus (a step of exposing the substrate), and the latent image pattern is formed in such a step. Developing the substrate. Further, the manufacturing method includes other well-known steps (oxidation, film formation, vapor deposition, doping, planarization, etching, resist stripping, dicing, bonding, packaging, etc.). The method for manufacturing an article according to the present embodiment is advantageous in at least one of the performance, quality, productivity, and production cost of the article as compared with the conventional method.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

60 Projection Optical System 65 Meniscus Lens 69 Convex Mirror 85 Second Air Supply Port 86 Second Exhaust Port 90 Switching Control Unit 100 Exposure Device

Claims (14)

An exposure apparatus that exposes a pattern of an original on a substrate via a projection optical system,
A gas supply means for supplying a gas to the optical element disposed in the vicinity of the pupil position of the projection optical system;
Control means for controlling the gas supply means,
The exposure apparatus characterized in that the control means controls the gas supply means so as to change a direction in which the gas is supplied in accordance with a temperature distribution of the optical element generated by exposure light exposure. The optical element includes an aspheric lens, and a convex mirror adjacent to the aspheric lens in the optical axis direction,
The gas supply means supplies the gas toward a space sandwiched between the aspheric lens and the convex mirror;
The exposure apparatus according to claim 1, wherein: The optical element includes a convex mirror,
The gas supply means supplies the gas toward the convex mirror.
The exposure apparatus according to claim 1, wherein:   4. The gas supply unit according to claim 1, wherein the gas supply unit includes a plurality of air supply ports that are arranged at different angles with respect to the optical axis of the optical element and that can supply the gas. 2. The exposure apparatus according to item 1.   The gas supply means includes a plurality of exhaust ports that are arranged symmetrically with respect to the position of the optical element with respect to the air supply port, and that can exhaust the gas supplied from the air supply port. The exposure apparatus according to claim 4.   6. The exposure apparatus according to claim 4, further comprising a temperature adjusting unit that is connected to the plurality of air supply ports and adjusts the temperature of the gas.   7. The exposure according to claim 4, wherein the gas supply unit includes a switching unit that enables switching of an air supply port that supplies the gas among the plurality of air supply ports. apparatus.   The control means predicts the temperature distribution based on the shape of the pattern, determines the air supply port that can supply the gas so that a direction in which the gas is supplied matches the temperature distribution, and determines the determination. The exposure apparatus according to claim 7, wherein the switching unit is controlled to switch to the supplied air supply port.   The exposure apparatus according to claim 8, wherein the control unit further predicts the temperature distribution based on an illumination condition when the original is illuminated during exposure.   The control means refers to a change in astigmatism that occurs in the vicinity of the pupil of the projection optical system, obtained by measurement in advance, and the direction in which the gas is supplied is a direction in which the change in astigmatism is greater than the other direction. The exposure apparatus according to claim 7, wherein the air supply port through which the gas can be supplied is determined so as to match, and the switching unit is controlled to switch to the determined air supply port.   The control unit causes the switching unit to switch the air supply port when exchanging the original plate with another original plate, when changing the illumination condition, or during regular maintenance. The exposure apparatus according to any one of claims 8 to 10. An exposure apparatus that exposes a pattern formed on an original on a substrate via a projection optical system,
A gas supply means for supplying a gas to the optical element disposed in the vicinity of the pupil position of the projection optical system;
Control means for controlling the gas supply means,
The control means changes the direction in which the gas is supplied according to the temperature distribution of the optical element generated by exposure light passing through the original plate on which the pattern is formed and entering the optical element. An exposure apparatus that controls the gas supply means. The pattern includes at least one line pattern;
The exposure apparatus according to claim 12, wherein the gas supply unit supplies the gas in a direction corresponding to an orientation of the at least one line pattern. A step of exposing the substrate using the exposure apparatus according to claim 1;
Developing the substrate exposed in the step;
A method for producing an article comprising:

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