Temperature adjustment apparatus, lithography apparatus, and article manufacturing method

Abstract

The temperature control device has a discharge section configured to discharge a temperature-controlled gas through an opening into the optical path of an optical system, and the shape of the outer circumference of the opening has a concave section that is sunken inward from the circumscribed circle of the opening, and if the position closest to the center of the circumscribed circle among the concave sections is any of the intersection point of two straight sections, the intersection point of two curved sections, and the intersection point of a straight section and a curved section, the angle on the inner side of the opening at the intersection point is 180 degrees or more.

Description

Technology Field

[0001] The present invention relates to a temperature control device, a lithography device, and a method for manufacturing an article. Background Technology

[0002] In manufacturing processes for semiconductor devices or liquid crystal display devices, optical systems such as illumination optical systems, projection optical systems, and / or measurement optical systems are used. If a temperature change occurs in the optical path of these optical systems, the performance of the optical systems may deteriorate due to the influence of the temperature change.

[0003] Japanese Patent Publication No. 2022-175879 discloses a method for reducing temperature changes around the optical path of a measuring optical system by ejecting gas from an ejection unit toward the optical path of a measuring optical system (measuring unit).

[0004] In this case, when a temperature-controlled gas is ejected into the optical path to reduce temperature changes in the optical path of the optical system, the ejected gas may spread in a direction perpendicular to the direction of ejection.

[0005] Accordingly, gas is ejected from the optical element of the optical system, causing the optical element to undergo a localized temperature change and degrade optical performance. The problem to be solved

[0006] The present invention aims to provide a temperature control device capable of adjusting the temperature of an optical path while reducing local temperature changes of an optical element of an optical system. means of solving the problem

[0007] According to one aspect of the present invention, a temperature control device has a discharge part configured to discharge a temperature-controlled gas through an opening into the optical path of an optical system, and the shape of the outer circumference of the opening has a concave part that is sunken inward from the circumscribed circle of the opening, and if the position closest to the center of the circumscribed circle among the concave parts is any of the intersection point of two straight parts, the intersection point of two curved parts, and the intersection point of a straight part and a curved part, the angle on the inner side of the opening at the intersection point is 180 degrees or more, and if the position closest to the center of the circumscribed circle among the concave parts is a curved part, the diameter of the curved part is 2 / 3 or less of the diameter of the circumscribed circle, and if the position closest to the center of the circumscribed circle among the concave parts is a straight part, the length of the straight part is 1 / 5 or less of the diameter of the circumscribed circle.

[0008] Another feature of the present invention will become apparent from the description of the following embodiments with reference to the accompanying drawings. Brief explanation of the drawing

[0009] FIG. 1 is a schematic diagram illustrating the configuration of a substrate processing apparatus according to a first embodiment. FIG. 2 is a schematic diagram illustrating a method for measuring the position of a fine adjustment stage using a laser interferometer. FIGS. 3a to 3d are drawings showing examples of the arrangement of a temperature control device according to the first embodiment, respectively. FIG. 4 is a drawing illustrating the configuration of the ejection part according to the first embodiment. FIGS. 5A and 5B are drawings illustrating the relationship between the maximum width of the light path and the width in which a plurality of openings are installed according to the first embodiment. FIGS. 6a, FIGS. 6b, and FIGS. 6c are drawings showing examples of openings according to the first embodiment, respectively. Figures 7a and 7b respectively show the simulation results of the gas flow velocity (speed) at the opening when the gas is ejected. FIGS. 8A and FIGS. 8B are drawings showing the flow state of gas ejected from the ejection section through the opening, respectively. FIGS. 9a to 9r are drawings showing examples of openings of the first embodiment, respectively. FIGS. 10a and FIGS. 10b are drawings showing the relationship between the sizes of the inscribed circle and the circumscribed circle of an opening according to the first embodiment, respectively. FIG. 11 is a flowchart illustrating a temperature control method according to a first embodiment. FIG. 12 is a flowchart illustrating a method for manufacturing an article according to a second embodiment. Specific details for implementing the invention

[0010] Hereinafter, embodiments of the present invention will be described based on the drawings. At this time, the following embodiments do not limit the invention with respect to the claims. Although multiple features are described in the embodiments, not all of these multiple features are essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the drawings, the same reference numerals are assigned to identical or similar components, and redundant descriptions are omitted. Each of the embodiments of the present invention described below may be implemented individually, or, if necessary, or if a combination of components or features from each of the single embodiments is advantageous, may be implemented as multiple embodiments or a combination of their features.

[0011] In addition, in this specification and drawings, the vertical direction is basically set as the Z-axis, the horizontal plane perpendicular to the vertical direction is set as the XY plane, and directions are indicated by an XYZ coordinate system in which the X, Y, and Z axes are orthogonal to each other. However, if an XYZ coordinate system is described in each drawing, that XYZ coordinate system takes precedence.

[0012] The specific configuration for each embodiment is described below.

[0013] FIG. 1 is a schematic diagram illustrating the configuration of a substrate processing device (1) according to a first embodiment. In this embodiment, the substrate processing device (1) is a projection exposure device configured to expose a pattern of a plate (i.e., a mask or reticle) to a substrate via a projection optical system by a step-and-repeat method or a step-and-scan method. However, the substrate processing device (1) is not limited to a projection exposure device. For example, the substrate processing device (1) may be a drawing device configured to perform drawing on a substrate by means of an electron beam or an ion beam, and to form a pattern on the substrate. In addition, the substrate processing device (1) may be another lithography device (substrate exposure device), for example, an imprint device configured to form a pattern on a substrate by molding an imprint material on the substrate using a mold. In contrast, the substrate processing device (1) may be another device configured to process a substrate such as a semiconductor wafer or a glass plate, for example, an ion implantation device, a developing device, an etching device, a film deposition device, an annealing device, a sputtering device, a deposition device, etc. Additionally, the substrate processing device (1) may be a flattening device configured to flatten a composition on the substrate using a flat plate.

[0014] A substrate processing device (1) has an illumination optical system (12) configured to irradiate light, a projection optical system (15), a reticle stage (14) configured to hold a reticle (13), a movable stage (20) that holds a substrate (16), an off-axis scope (OAS) (30), and a first control unit (11).

[0015] The stage (20) has an XY stage (23) movable in the XY plane, a fine adjustment stage (22) mounted on the XY stage (23) and movable, and a substrate chuck (21) configured to hold a substrate (16) while held on the fine adjustment stage (22). The fine adjustment stage (22) is movable (driven) in the X-axis direction, Y-axis direction, Z-axis direction (optical axis direction of the projection optical system (15)), θX-axis direction, θy-axis direction, and θz-axis direction. That is, the fine adjustment stage (22) is movable (driven) in six axis directions. In this embodiment, the θX-axis direction is the rotation direction around the X-axis, the θy-axis direction is the rotation direction around the Y-axis, and the θz-axis direction is the rotation direction around the Z-axis. In addition, the position in the θX axis direction represents the angle of rotation around the X-axis, the position in the θy axis direction represents the angle of rotation around the Y-axis, and the position in the θz axis direction represents the angle of rotation around the Z-axis.

[0016] The reticle (13) is a plate on which a pattern (e.g., a circuit pattern) to be transferred onto the surface of a quartz glass is formed of chrome. In addition, when the substrate (16) is, for example, a single-crystal silicon substrate and the substrate processing device (1) is an exposure device, a photosensitive material (resist) is applied to the surface of the substrate (16) that is returned to the substrate processing device (1). Here, the illumination optical system (12) is a pattern forming unit configured to form a pattern on the substrate (16). Furthermore, in this embodiment, an example of a lithography device that forms a pattern using light is shown, and an example of a pattern forming unit is the illumination optical system (12), but a lithography device that cures a thermosetting material by heat may also be used. In this case, the pattern forming unit is, for example, a heating unit configured to heat the thermosetting material. The control unit (11) controls each component within the substrate processing device (1).

[0017] The off-axis scope (30) is used to determine the position of the substrate (16) and to detect the position of a plurality of pattern regions on the substrate (16). The off-axis scope (30) detects the relative position and orientation relationship between an alignment mark (not shown) formed on the substrate (16) and a reference mark (not shown) on the fine adjustment stage (22). The substrate processing device (1) determines the position of the stage (20) (substrate (16)) based on the measurement results of the off-axis scope (30) and the measurement results obtained using a laser interferometer and a bar mirror described later.

[0018] In a substrate processing device (1), exposure light from a light source (not shown) passes through an illumination optical system (12) and illuminates a reticle (13) held on a reticle stage (14). The light transmitted through the reticle (13) passes through a projection optical system (15) and is irradiated onto a substrate (16). At this time, light from a pattern formed on the reticle (13) is formed on the surface of the substrate (16). The substrate processing device (1) thus exposes a shot area on the substrate (16) and similarly performs exposure for each of a plurality of shot areas.

[0019] FIG. 2 is a schematic diagram showing a method of measuring the position of a fine adjustment stage (22) by a laser interferometer. The position of the fine adjustment stage (22) in the X-axis direction is measured using an X-bar mirror (100) and a laser interferometer 110. The position of the fine adjustment stage (22) in the Y-axis direction is measured using a Y-bar mirror (200) and a laser interferometer 210. The X-bar mirror (100) is installed to extend in the Y-axis direction on the side of the fine adjustment stage (22), and the Y-bar mirror (200) is installed to extend in the X-axis direction on the side of the fine adjustment stage (22).

[0020] First, a method for measuring the position of the fine adjustment stage (22) in the X-axis direction is described. The laser interferometer 110 includes three laser interferometers 111, 112, and 113. Laser interferometer 112 is positioned at the same horizontal position as laser interferometer 111 (i.e., the same position in the X-axis and the same position in the Y-axis), and is spaced Δz in the height direction (i.e., Z-axis direction) from laser interferometer 111. Based on the measurement results of this laser interferometer 111 and laser interferometer 112, the amount of misalignment θy in the rotation direction around the Y-axis can be measured. Laser interferometer 113 is positioned at the same height position as laser interferometer 111 (i.e., the same position in the Z-axis direction), and is spaced Δy in the horizontal direction (i.e., Y-axis direction) from laser interferometer 111. Based on the measurement results of this laser interferometer 111 and laser interferometer 113, the amount of misalignment θz in the rotational direction around the Z-axis in the XY plane can be measured.

[0021] Next, a method for measuring the position of the fine adjustment stage (22) in the Y-axis direction will be described. The laser interferometer 210 includes three laser interferometers 211, 212, and 213. Laser interferometer 212 is positioned at the same horizontal position as laser interferometer 211 (i.e., the same position in the X-axis and also the same position in the Y-axis), and is spaced Δz in the height direction (i.e., Z-axis direction) from laser interferometer 211. Based on the measurement results of this laser interferometer 211 and laser interferometer 212, the amount of misalignment θx in the rotation direction around the X-axis can be measured. Laser interferometer 213 is positioned at the same height position as laser interferometer 211 (i.e., the same position in the Z-axis direction), and is spaced Δx in the horizontal direction (X-axis direction) from laser interferometer 211. Based on the measurement results of the laser interferometer 211 and the laser interferometer 213, the amount of misalignment θz in the rotational direction around the Z-axis within the XY plane can be measured. With the above configuration, the position of the fine adjustment stage (22) is measured. In this embodiment, bar mirrors 100 and 200 are installed on the side of the fine adjustment stage (22), but the installation position is not limited to this, and the bar mirrors 100 and 200 may be installed on the upper part of the fine adjustment stage (22). Furthermore, the off-axis scope (30) and the laser interferometers 110 and 210 are each measurement optical systems.

[0022] In this embodiment, a temperature change may occur in the optical path of an optical system such as an off-axis scope (30), a laser interferometer 110, a laser interferometer 210, a projection optical system (15), and an illumination optical system (12). This temperature change is caused by, for example, heat generated during substrate processing (for example, exposure heat generated during exposure), driving heat generated when the stage (20) is driven, and heat from a driving unit or encoder installed in the measurement optical system. When such a temperature change occurs, the performance of the optical system deteriorates due to the influence of the temperature change. When a temperature-controlled gas is ejected into the optical path to reduce the temperature change in this optical path, the ejected gas may spread in a direction perpendicular to the direction of ejection. In this case, the gas is ejected onto the optical element of the optical system, causing the optical element to undergo a local temperature change, thereby degrading the optical performance. Furthermore, if the gas is ejected onto the optical element of the optical system or the substrate (16), the object onto which the gas is ejected vibrates, thereby degrading the optical performance or measurement precision. The temperature control device according to the present embodiment can adjust the temperature of the optical path while reducing local temperature changes of the optical elements of the optical system or vibrations of the object caused by gas ejection. The optical path of the optical system according to the present embodiment is an optical path through which one or more light rays pass.

[0023] FIGS. 3a to 3d are examples showing the arrangement of a temperature control device according to the present embodiment. FIG. 3a shows a temperature control device (50) configured to eject a temperature-controlled gas into the optical path of an off-axis scope (30) in order to reduce temperature changes in the optical path of an off-axis scope (30). The temperature control device (50) has a temperature control unit (61) configured to perform temperature control of the gas, an ejection unit (52) configured to eject the gas through an opening (opening) or openings, a pipe (60) which is a gas flow path connecting the ejection unit (52) and the temperature control unit (61), and a second control unit (62) configured to control the temperature control device (50). The opening is a hole installed in the ejection unit (52). Alternatively, a first control unit (11) configured to control a substrate processing device (1) may control the temperature control device (50).

[0024] If the temperature in the optical path of the off-axis scope (30) changes, an error occurs in the measurement result. The temperature control device (50) according to the present embodiment discharges a temperature-controlled gas with respect to this optical path. For example, measurement may not be performed using the off-axis scope (30) until the value of the sensor capable of measuring the temperature in the optical path of the off-axis scope (30) reaches the desired temperature, and the off-axis scope (30) may perform measurement after the temperature in the optical path reaches the desired temperature. Accordingly, the error in the measurement result of the off-axis scope (30) can be reduced. The temperature control of the gas is performed by the temperature control unit (61), and the gas temperature-controlled by the temperature control unit (61) is supplied to the discharge unit (52) through the pipe (60). FIG. 3b shows a temperature control device (50) configured to spray a temperature-controlled gas into the optical paths of laser interferometer 110 and laser interferometer 210, respectively, in order to reduce temperature changes in the optical paths of laser interferometer 110 and laser interferometer 210. FIG. 3c shows a temperature control device (50) configured to spray a temperature-controlled gas into the optical path of a projection optical system (15) in order to reduce temperature changes in the optical path of a projection optical system (15). FIG. 3d shows a temperature control device (50) configured to spray a temperature-controlled gas into the optical path of an illumination optical system (12) in order to reduce temperature changes in the optical path of an illumination optical system (12). In FIG. 3d, the temperature control device (50) sprays gas onto the upper region (+Z side region) of the reticle (13) and the lower region (-Z side region) of the reticle stage (14). In this way, the temperature control device (50) according to the present embodiment sprays temperature-controlled gas onto at least one optical path (peripheral region of the optical system) of the optical system (off-axis scope (30), laser interferometer 110 and 210, projection optical system (15), illumination optical system (12)).In this embodiment, the arrangement of the temperature control device (50) is not limited to the examples of FIG. 3a, FIG. 3b, FIG. 3c, and FIG. 3d, and the number and location of the temperature control device (50) are not limited to these. The temperature control device (50) may be arranged to blow gas into the optical path of at least one optical system, such as the off-axis scope (30), the laser interferometer, the projection optical system (15), and the illumination optical system (12). Alternatively, the temperature control device (50) may be arranged in each of the optical paths of multiple optical systems. Furthermore, in the example of FIG. 3b, two temperature control devices (50) are arranged to blow gas into each of the optical paths of the laser interferometer 110 and the laser interferometer 210, but the temperature control device (50) may be installed only in the optical path where the temperature change is large. Moreover, in the example of FIG. 3d, a temperature control device (50) configured to eject temperature-controlled gas to the upper region (+Z side region) of the reticle (13) and the lower region (-Z side region) of the reticle stage (14) was described, but the temperature control device (50) may eject gas to only one of the regions. Also, in the example of FIG. 3d, an example was shown in which two ejection units (52) are arranged and one temperature control unit (61) and one second control unit (62) are arranged by branching the pipe (60), but two temperature control units (61) and two second control units (62) may be arranged without branching the pipe (60).

[0025] FIG. 4 is a drawing illustrating the configuration of the discharge section (52) according to the present embodiment. In FIG. 4, it is not necessary to make all cross-sectional shapes of the flow paths through which gas flows within the discharge section (52) the shape of the opening (51), and the cross-sectional shape of the flow paths other than the flow path portion near the opening (51) (the flow paths on the pipe (60) side) may be circular or square. Also, in the example of FIG. 4, multiple openings (51) having one type of shape are installed, but openings with different shapes (multiple types of shapes) may be installed.

[0026] In addition, for temperature control of the optical path area, it is preferable that multiple openings (51) be installed. Also, it is preferable that the width of the multiple openings (51) installed is greater than the maximum width of the optical path in the direction perpendicular to the gas ejection direction in the XY plane (i.e., the plane perpendicular to the optical path of the optical system). FIGS. 5A and 5B are drawings illustrating the relationship between the maximum width of the optical path and the width of the multiple openings (51) installed according to the present embodiment. FIG. 5A is a schematic diagram showing the state viewed from the +X direction side when the temperature control device (50) ejects gas into the optical path (31) of the off-axis scope (30). As shown in FIG. 5A, the optical path of the off-axis scope (30) passes through the entire surface of the lower region (-Z direction side region) of the off-axis scope (30). FIG. 5b is a schematic diagram showing the state viewed from the +Z direction side when a temperature control device (50) ejects gas into the light path (31) of an off-axis scope (30). In the plane (XY plane) perpendicular to the light path (31) of the optical system (off-axis scope (30)), the maximum width of the light path (31) in the direction perpendicular to the gas ejection direction (Y direction) is width W1. And, the width where a plurality of openings (51) are installed in the temperature control device (50) is width W2. In this case, the width W2 where a plurality of openings (51) are installed is larger than the maximum width W1 of the light path in the direction perpendicular to the gas ejection direction in the plane perpendicular to the light path (31). Accordingly, when the ejection part (52) ejects gas through the opening (51), the temperature of the entire light path can be adjusted. In this embodiment, an example is shown in which a temperature control device (50) is arranged such that a plurality of openings (51) are arranged along the X-axis or Y-axis, but a temperature control device (50) may also be arranged such that a plurality of openings (51) are arranged along the Z-axis.

[0027] For example, it is possible to form the shape of the complex opening (51) of the temperature control device (50) by using a three-dimensional (3D) printer. Alternatively, it is possible to form the shape of the complex opening (51) by combining two or more parts after cutting each of them. Alternatively, the temperature control device (50) can be manufactured by using means such as wire cutting, laser processing, and welding. Furthermore, when manufacturing the temperature control device (50) with a 3D printer, irregularities may occur in the gas flow path of the temperature control device (50), and as these irregularities peel off and are ejected along with the gas, the inside of the substrate processing device (1) may be contaminated with particles. Therefore, when manufacturing the temperature control device (50) with a 3D printer, it is preferable to perform polishing or plating treatment on the inner wall surface of the gas flow path of the temperature control device (50).

[0028] FIGS. 6a, FIGS. 6b, and FIGS. 6c each illustrate an example of an opening (51) according to the present embodiment. The outer circumference of each opening (51) of the temperature control device (50) according to the present embodiment has a concave portion (53) that is recessed inward from the outer circumference of the circumscribed circle (59) of each opening (51). Each concave portion (53) has an intersection point (55) (Fig. 6a), a curved portion (56) (Fig. 6b), or a straight portion (57) (Fig. 6c) at a position closest to the center (54), which is the center of the circumscribed circle (59). In this case, the center (54) is also the center of each opening (51).

[0029] FIG. 6a is an example having an intersection point (55) at the position closest to the center (54) of the circumscribed circle (59). FIG. 6b is an example having a curved section (56) at the position closest to the center (54) of the circumscribed circle (59). FIG. 6c is an example having a straight section (57) at the position closest to the center (54) of the circumscribed circle (59).

[0030] As illustrated in FIG. 6a, in the case where the intersection point (55) is located closest to the center (54), each intersection point (55) is any one of the intersection points of two straight sections, two curved sections, and the intersection points of the straight section and the curved section. The angle on the inner side of the opening (51) at the intersection point (55) is greater than 180 degrees.

[0031] As shown in FIG. 6b, when the curved portion (56) is located closest to the center (54), the diameter of the curved portion (56) is less than or equal to two-thirds of the diameter of the circumscribed circle (59). In this case, it is more preferable that the diameter of the curved portion (56) be less than or equal to half (more preferably less than or equal to one-third) of the diameter of the circumscribed circle (59).

[0032] As shown in FIG. 6c, when a straight section (57) is positioned closest to the center (54), the length of the straight section (57) is less than or equal to one-fifth of the diameter of the circumscribed circle (59). In this case, it is more preferable that the length of the straight section (57) is less than or equal to one-tenth of the diameter of the circumscribed circle (59) (more preferably less than or equal to one-twentieth).

[0033] The opening (51) according to the present embodiment has the above-described characteristics, and by ejecting gas through the opening (51) having these characteristics, the gas ejected around the location of the intersection (55), curved section (56), or straight section (57) becomes turbulent. Furthermore, the gas ejected at a location closer to the center (54) than at the location of the intersection (55), curved section (56), or straight section (57) of the opening (51) becomes a laminar flow with a fast flow velocity and a small difference in flow velocity.

[0034] FIGS. 7A and FIGS. 7B respectively show the results of simulating the gas flow velocity (speed) at the opening when the gas is ejected. In the upper drawings of FIGS. 7A and FIGS. 7B, the darker colored parts indicate a fast gas flow velocity, and the lighter colored parts indicate a slow gas flow velocity. In the simulations shown in FIGS. 7A and FIGS. 7B, the flow source condition is set to 10 L / min, and the colors of the figures are divided into three stages according to the gas flow velocity at the opening (51). When the gas flow velocity is fast (3 m / s or more), the color is the darkest; when the gas flow velocity is moderate (1.5 m / s or more and less than 3.0 m / s), the color is the second darkest; and when the gas flow velocity is slow (less than 1.5 m / s), the color is the third darkest (lightest). The lower drawings of FIGS. 7a and FIGS. 7b, respectively, show the relationship between the position at the dotted line location of the upper drawing and the corresponding gas flow velocity.

[0035] FIG. 7a shows the result of simulating the gas flow velocity in the opening (51) according to the present embodiment. FIG. 7b shows the result of simulating the gas flow velocity in a circular opening without a concave part. The area of ​​the region where the gas flow velocity is fast (3 m / s or more) in FIG. 7a is larger than the area of ​​the region where the gas flow velocity is fast (3 m / s or more) in FIG. 7b. That is, the area where the gas flow velocity is fast in the opening (51) according to the present embodiment is larger than the area where the gas flow velocity is fast in the circular opening. This is because in the opening (51) according to the present embodiment, turbulence occurs at the intersection point (55), the curved part (56), or the straight part (57), and a high-velocity laminar flow flows at the location surrounded by the turbulence (near the center).

[0036] The ejected gas loses speed due to friction (shear force) at the outer periphery (wall surface) of the opening. In the case of the circular opening of FIG. 7b, laminar flow occurs throughout the opening (51), and since the gas speed is significantly lost at the outer periphery (wall surface) of the opening, the area of ​​the region where the gas flow velocity is high is small. Accordingly, the difference in gas flow velocity near the center of the opening (51) is large.

[0037] The opening (51) according to the present embodiment generates turbulence at the intersection (55), the curved section (56), or the straight section (57), and since a high-velocity laminar flow flows at a location surrounded by turbulence, the loss of velocity of the laminar flow near the center can be suppressed. As a result, the area of ​​the region where the gas flow velocity is high (3 m / s or more) near the center increases, and the difference in gas flow velocity near the center of the opening (51) can be reduced. By increasing the area where the gas flow velocity is high and reducing the difference in the flow velocity of the ejected gas, the diffusion (spreading) of the gas ejected from the ejection section (52) through the opening (51) can be reduced.

[0038] FIGS. 8A and FIGS. 8B respectively show the flow of gas ejected from the ejection part (52) through the opening. FIG. 8A shows the flow of gas when gas is ejected from the ejection part (52) through the opening (51) according to the present embodiment. FIG. 8B shows the flow of gas when gas is ejected from the ejection part (52) through the circular opening. FIG. 8A, which shows the result of ejecting gas through the opening (51) according to the present embodiment, indicates that the diffusion (spreading) of the gas is reduced compared to FIG. 8B, which shows the result of ejecting gas through the circular opening. Furthermore, when gas is ejected through the opening (51) according to the present embodiment, not only is the diffusion of the gas reduced, but the directionality (straightness) can also be increased. Moreover, in the simulation of the gas flow, compared to the case where gas is ejected from a circular opening, when gas is ejected from the opening (51) according to the present embodiment, the diffusion of gas at a position 17 mm away from the opening (51) can be reduced by about 23%.

[0039] FIGS. 9a to 9r are drawings showing examples of an opening (51) according to the present embodiment. However, the opening (51) according to the present embodiment is not limited to the examples of FIGS. 9a to 9r, and the shape of the outer circumference of the opening (51) satisfies the following characteristics. The shape of the outer circumference of the opening (51) has a concave portion (53) that is sunken inward from the outer circumference of the circumscribed circle (59) of the opening (51). Each of the concave portions (53) has an intersection point (55), a curved portion (56), or a straight portion (57) at the position closest to the center (54) of the circumscribed circle (59). In the case where the intersection point (55) is at the position closest to the center (54), each intersection point (55) is one of the intersection point of two straight portions, the intersection point of two curved portions, and the intersection point of a straight portion and a curved portion. And, the inner angle of the opening (51) at each intersection point (55) should be greater than 180 degrees. When a curved section (56) is located closest to the center (54) of the circumscribed circle (59), the diameter of the curved section (56) should be 2 / 3 or less of the diameter of the circumscribed circle (59). In this case, it is more preferable that the diameter of each curved section (56) be 1 / 2 or less (more preferably 1 / 3 or less) of the diameter of the circumscribed circle (59). When a straight section (57) is located closest to the center (54) of the circumscribed circle (59), the length of each straight section (57) is 1 / 5 or less of the diameter of the circumscribed circle (59). In this case, it is more preferable that the length of the straight section (57) be 1 / 10 or less (more preferably 1 / 20 or less) of the diameter of the circumscribed circle (59). Additionally, each concave portion (53) according to the present embodiment may have a shape in which a partition is inserted into a circular opening, for example, as shown in FIG. 9q and FIG. 9r.

[0040] FIGS. 10a and FIGS. 10b are drawings showing the relationship between the size of the inscribed circle (58) and the circumscribed circle (59) of the opening (51) according to the present embodiment. In the opening (51) according to the present embodiment, the relationship between the diameter of the inscribed circle (58) of the opening (51) and the diameter of the circumscribed circle (59) that contacts the multiple intersection points (55), multiple curved sections (56), or multiple straight sections (57) of the opening (51) is related to the temperature control performance of the temperature control device (50). For example, as shown in FIG. 10a, if the diameter of the inscribed circle (58) is larger than two-thirds of the diameter of the circumscribed circle (59), the turbulence generated at the intersection points (55), the curved sections (56), or the straight sections (57) cannot surround the laminar flow near the center. Accordingly, the effect of reducing the difference in gas flow velocity near the center of the opening (51) and the effect of reducing the diffusion of the ejected gas are reduced. For this reason, it is preferable that the diameter of the inscribed circle (58) of the opening (51) that contacts the intersection point (55), the curved section (56), or the straight section (57) is 2 / 3 or less of the diameter of the circumscribed circle (59). In this case, it is even more preferable that the diameter of the inscribed circle (58) of the opening (51) is 3 / 5 or less (more preferably 1 / 2 or less) of the diameter of the circumscribed circle (59).

[0041] In addition, as shown in FIG. 10b, if the diameter of the inscribed circle (58) is less than one-tenth of the diameter of the circumscribed circle (59), the area of ​​laminar flow near the center surrounded by turbulence generated at the intersection (55), the curved section (56), or the straight section (57) is reduced, and the effect of reducing temperature change in the optical path is reduced. For this reason, it is preferable that the diameter of the inscribed circle (58) of the opening (51) that contacts the intersection (55), the curved section (56), or the straight section (57) be at least one-tenth (more preferably at least one-fourth) of the diameter of the circumscribed circle (59).

[0042] Next, the timing for ejecting gas through the opening (51) from the ejection part (52) of the temperature control device (50) according to the present embodiment will be explained. For example, when the gas ejected from the ejection part (52) diffuses, the optical element undergoes a local temperature change because the gas is ejected to the optical element. When the injection of this gas is stopped, the temperature at the location where the local temperature change occurred returns to normal, and the optical performance may differ between when the gas is being ejected and when the gas is not being ejected.

[0043] In order to reduce this change in optical performance, when the gas ejected from the ejection unit (52) diffuses, it was necessary to constantly eject the gas even when replacing the substrate. However, since the temperature control device (50) according to the present embodiment can reduce the diffusion of the gas, it does not cause local temperature changes in the optical element, and even when the gas injection is stopped, the change in optical performance between when the gas is being ejected and when the gas is not being ejected is small. Therefore, when replacing the substrate or performing maintenance, the gas injection can be stopped, and the gas can be ejected only when using the optical system of the optical path that ejects the gas.

[0044] Additionally, the flow rate and temperature of the gas ejected from the ejection unit (52) may be adjusted. For example, in the case where a temperature sensor is attached to an optical element (e.g., an objective lens) corresponding to the path for ejecting the gas to achieve a target temperature, the second control unit (62) may adjust the flow rate and temperature of the gas ejected from the ejection unit (52) based on the value output from the temperature sensor. In this case, the temperature sensor may not measure the temperature of the optical element, but may be positioned so that the temperature sensor can measure the temperature in the optical path. Alternatively, even if a temperature sensor is not installed, the second control unit (62) may predict a temperature change from substrate processing conditions, etc., and adjust the flow rate and temperature of the gas ejected from the ejection unit (52) based on the predicted result. In this case, adjusting the temperature by the second control unit (62) is equivalent to controlling the temperature adjustment unit (61) so that the optical element reaches the desired temperature. Moreover, in the case where multiple openings (51) are installed, the second control unit (62) may select an opening (51) to use from all openings (51) and control the supply of gas through the selected opening (51).

[0045] FIG. 11 is a flowchart illustrating a temperature control method according to the present embodiment. First, in step S110, the second control unit (62) sets the target temperature of the gas to be ejected (target setting process). Next, in step S120, the second control unit (62) controls the temperature control unit (61) to adjust the temperature of the gas so that it reaches the target temperature set in step S110 (temperature control process). Next, in step S130, the second control unit (62) ejects the gas whose temperature was adjusted in step S120 into the optical path of the optical system through the opening (51) (ejection process). In this way, temperature control is performed in the present embodiment. Furthermore, the shape of the outer circumference of the opening (51) of the temperature control device (50) used in the ejection process has the same characteristics as described above.

[0046] As described above, since the temperature change in the optical path is reduced by the temperature control device (50) according to the present embodiment, the diffusion (spreading) of the temperature-controlled gas ejected from the ejection part (52) through the opening (51) is reduced. Accordingly, the ejection of the gas ejected from the ejection part (52) through the opening (51) to the optical element of the optical system can be reduced, and the temperature change in the optical path can be reduced while reducing the degradation of optical performance caused by local temperature changes of the optical element. Furthermore, the degradation of optical performance or measurement precision caused by the object (optical element or substrate (16)) vibrating as the gas ejected through the opening (51) is ejected to the optical element of the optical system or the substrate (16) can be reduced. In addition, by blowing a temperature-controlled gas into the optical path of the optical system, deformation of an object (substrate (16), reticle (13), or optical element) placed around the optical path, which is deformed by temperature changes, can be suppressed. Furthermore, although the present embodiment shows an example in which the gas blown from the temperature control device (50) is temperature-controlled, a humidity-controlled gas may be blown in addition to the temperature-controlled gas.

[0047] The second embodiment is characterized by manufacturing an article using the aforementioned temperature control device (50).

[0048] FIG. 12 is a flowchart illustrating a method for manufacturing an article according to the present embodiment. First, in step S210, a substrate (16) is exposed using a lithography device in an exposure process. In step S220, the substrate (16) exposed in the exposure process is developed in a development process. Then, in step S230, a manufacturing process is performed to manufacture an article from the substrate (16) developed in the development process. In the present embodiment, the lithography device used in the exposure process has an illumination optical system (12) configured to illuminate a reticle (plate) (13) by light from a light source, and a projection optical system (15) configured to project light from the reticle (plate) (13) onto the substrate (16). The lithography device further has a measurement optical system configured to measure the position of a stage (20) configured to hold the substrate (16) or the position of the substrate (16). Furthermore, the lithography device has a temperature control device (50) having an ejection part (52) configured to eject a temperature-controlled gas through an opening (51) for the light path of at least one of the illumination optical system (12), the projection optical system (15), and the measurement optical system. The opening (51) is a hole installed in the ejection part (52).

[0049] The shape of the outer circumference of each of these openings (51) has a concave portion (53) that is sunken inward from the circumscribed circle (59) of each opening (51). In each of the concave portions (53), if the position closest to the center of the circumscribed circle (59) is the intersection of two straight sections, the intersection of two curved sections, or the intersection of a straight section and a curved section, the angle of the inner side of the opening (51) at this intersection is greater than 180 degrees. In each of the concave portions (53), if the position closest to the center of the circumscribed circle (59) is a curved section, the diameter of the curved section is less than or equal to two-thirds of the diameter of the circumscribed circle (59). In each of the concave portions (53), if the position closest to the center of the circumscribed circle (59) is a straight section, the length of the straight section is less than or equal to one-fifth of the diameter of the circumscribed circle (59).

[0050] Examples of articles manufactured by this manufacturing method include, for instance, semiconductor integrated circuit (IC) devices, liquid crystal display devices, color filters, and microelectromechanical systems (MEMS).

[0051] The manufacturing process includes, for example, an etching step, a resist stripping step, a dicing step, a bonding step, and a packaging step performed on a developed substrate. According to the present manufacturing method, articles of higher quality than conventional articles can be manufactured.

[0052] The present invention is not limited to the above embodiments, and various changes and modifications are possible without departing from the spirit and scope of the invention. Accordingly, claims are appended to clarify the scope of the invention.

[0053] According to the present invention, a temperature control device capable of adjusting the temperature of a light path while reducing local temperature changes of an optical element of an optical system can be provided.

[0054] Although the present invention has been described with reference to exemplary embodiments, it is obvious that the invention is not limited to these embodiments. The scope of protection of the following claims shall be interpreted as broadly as possible to encompass all variations, equivalent structures, and functions.

Claims

Claim 1 A discharge unit configured to discharge a temperature-controlled gas through an opening into the optical path of an optical system, wherein the shape of the outer circumference of the opening has a concave portion recessed inward from the circumscribed circle of the opening, and the opening satisfies at least one of the following conditions (i), (ii), and (iii): (i) if the position closest to the center of the circumscribed circle among the concave portions is any of the intersection point of two straight sections, the intersection point of two curved sections, and the intersection point of a straight section and a curved section, the angle on the inner side of the opening at the intersection point is 180 degrees or more; (ii) if the position closest to the center of the circumscribed circle among the concave portions is a curved section, the diameter of the curved section is 2 / 3 or less of the diameter of the circumscribed circle; (iii) if the position closest to the center of the circumscribed circle among the concave portions is a straight section, the length of the straight section is 1 / 5 or less of the diameter of the circumscribed circle; and when the discharge unit discharges the temperature-controlled gas through the opening, the A temperature control device in which the shape of the outer circumference of the opening generates a laminar flow of temperature-controlled gas at the center of the opening. Claim 2 A temperature control device according to claim 1, wherein the shape of the outer circumference of the opening has a plurality of concave portions, and the diameter of the inscribed circle of the opening that touches the intersection point closest to the center of the circumscribed circle, the curved portion, or the straight portion in each of the plurality of concave portions is 2 / 3 or less of the diameter of the circumscribed circle. Claim 3 A temperature control device according to claim 1, wherein the shape of the outer circumference of the opening has a plurality of concave portions, and the diameter of the inscribed circle of the opening that touches the intersection point closest to the center of the circumscribed circle, the curved portion, or the straight portion in each of the plurality of concave portions is at least one-tenth of the diameter of the circumscribed circle. Claim 4 In claim 1, the shape of the outer circumference of the opening comprises at least three concave portions, forming a temperature control device. Claim 5 A temperature control device according to claim 1, wherein the optical system comprises at least one of an illumination optical system configured to illuminate a disc, a projection optical system configured to project light from the disc onto a substrate, and a measurement optical system configured to measure the position of a stage configured to hold the substrate or the position of the substrate. Claim 6 In claim 1, the above-mentioned discharge portion is a temperature control device that discharges the gas into the light path through a plurality of the above-mentioned openings. Claim 7 A temperature control device having a width greater than the maximum width of the optical path in a direction perpendicular to the direction of gas ejection in a plane perpendicular to the optical path in the first paragraph, wherein a plurality of the openings are installed. Claim 8 A temperature control device according to claim 1, further comprising a temperature control unit configured to adjust the temperature of the gas ejected by the ejection unit, and a control unit configured to control the temperature control unit based on the measurement result of the temperature in the optical path of the optical system or the temperature of the optical element of the optical system. Claim 9 A temperature control device according to claim 1, further comprising a control unit configured to control and adjust the flow rate of the ejected gas based on the measurement result of the temperature in the optical path of the optical system or the temperature of the optical element of the optical system. Claim 10 A temperature control device according to claim 1, further comprising a temperature control unit configured to adjust the temperature of the gas ejected by the ejection unit, and a control unit configured to control the temperature control unit based on the predicted result of a temperature change in the optical path of the optical system. Claim 11 A temperature control device according to claim 1, further comprising a control unit configured to control and adjust the flow rate of the gas based on the predicted result of the temperature change in the optical path of the optical system. Claim 12 In claim 6, a temperature control device comprising a plurality of openings having different shapes. Claim 13 A temperature control device according to claim 1, further comprising a control unit configured to select an opening to be used among a plurality of the above-mentioned openings. Claim 14 A temperature control device having an illumination optical system configured to illuminate a disc by light from a light source, a projection optical system configured to project light from the disc onto a substrate, a measurement optical system configured to measure the position of a stage configured to hold the substrate or the position of the substrate, and a discharge unit configured to discharge a temperature-controlled gas through an opening in a peripheral area of ​​at least one of the illumination optical system, the projection optical system, and the measurement optical system, wherein the shape of the outer circumference of the opening has a concave portion recessed inward from the circumscribed circle of the opening, and the opening satisfies at least one of the following conditions (i), (ii), and (iii): (i) if the position closest to the center of the circumscribed circle among the concave portion is any of the intersection point of two straight sections, the intersection point of two curved sections, and the intersection point of a straight section and a curved section, the angle on the inner side of the opening at the intersection point is 180 degrees or more, and (ii) if the position closest to the center of the circumscribed circle among the concave portion is a curved section In the case where the diameter of the curved portion is less than or equal to two-thirds of the diameter of the circumscribed circle, (iii) where the position closest to the center of the circumscribed circle among the concave portions is a straight portion, the length of the straight portion is less than or equal to one-fifth of the diameter of the circumscribed circle, and when the ejection portion ejects temperature-controlled gas through the opening, the shape of the outer circumference of the opening generates a laminar flow of temperature-controlled gas at the center of the opening. Claim 15 The method comprises the steps of exposing a substrate using a lithography device, developing the exposed substrate, and manufacturing an article from the developed substrate, wherein the lithography device comprises an illumination optical system configured to illuminate a plate by light from a light source, a projection optical system configured to project light from the plate onto the substrate, a measurement optical system configured to measure the position of a stage configured to hold the substrate or the position of the substrate, and a temperature control device having a discharge part configured to discharge a temperature-controlled gas through an opening in a peripheral area of ​​at least one of the illumination optical system, the projection optical system, and the measurement optical system, wherein the shape of the outer circumference of the opening has a concave portion that is recessed inward from the circumscribed circle of the opening, and the opening satisfies at least one of the following conditions (i), (ii), and (iii), and (i) if the position closest to the center of the circumscribed circle among the concave portion is any of the intersection point of two straight sections, the intersection point of two curved sections, and the intersection point of a straight section and a curved section, the A method for manufacturing an article in which, when the ejection part ejects temperature-controlled gas through the opening, the shape of the outer circumference of the opening generates a laminar flow of temperature-controlled gas at the center of the opening.

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