TW202314397A - Holding device, exposure device and method for manufacturing article capable of suppressing deterioration in optical performance - Google Patents

Abstract

The invention provides a holding device, an exposure device and a method for manufacturing an article. The holding device is provided to hold an optical element, and has a base, a first holding portion for holding the optical element and the base, and a second holding portion for holding the optical element and the base at a position different from the holding position where the first holding portion holds the optical element. It is configured such that the rigidity of at least one of the first holding portion and the second holding portion can be changed.

Description

Holding device, exposure device and manufacturing method of article

The present invention relates to a holding device, an exposure device and a method for manufacturing an article.

In the manufacture of liquid crystal panels, organic EL displays, semiconductor devices, etc., an exposure device that exposes a substrate coated with a photosensitive material in an original pattern via a projection optical system is used. Since the exposure device needs to transfer a fine pattern with high precision, it is required to hold the optical element mounted on the exposure device with high precision.

Japanese Patent Application Laid-Open No. 2021-005018 discloses a holding device including a mechanism capable of restoring the surface shape of an optical element deformed by its own weight to a state before deformation. In addition, specially opened in Japan Publication No. 2021-005018 describes a method for removing stress locally generated in an optical element.

[Problem to be Solved by the Invention]

In addition, the optical element mounted in the exposure device may affect the exposure accuracy due to the generation of a vibration mode due to the influence of external disturbance. In Japanese Unexamined Patent Application Publication No. 2021-005018, the problem that the vibration generated in the optical element adversely affects the exposure accuracy is not recognized, and the countermeasure against the vibration generated in the optical element is not disclosed. In particular, the vibration mode that rotates around an axis perpendicular to the optical axis of the optical element may be one of the causes of deterioration in optical performance because the sensitivity of the optical element is higher than other vibration modes.

Accordingly, an object of the present invention is to provide a holding device that is advantageous in suppressing a decrease in optical performance. [Content of the invention]

In order to achieve the foregoing object, a holding device as one aspect of the present invention is a holding device that holds an optical element and has: a base; a first holding portion that holds the optical element and the base; and a second holding portion that is in contact with the optical element. The first holding portion holds the optical element and the substrate at different holding positions of the optical element, and is configured such that rigidity of at least one of the first holding portion and the second holding portion can be changed. Further features of the present invention will become apparent from the following embodiments (below referring to the drawings).

Hereinafter, preferred embodiments of the present invention will be described in detail based on the drawings. In addition, in each figure, the same reference numerals are assigned to the same members, and overlapping descriptions are omitted.

<First Embodiment> Referring to FIG. 1 , the holding device 100 for holding the optical element 1 will be described. FIG. 1( a ) and FIG. 1( b ) are diagrams illustrating the configuration of a holding device 100 according to this embodiment. In this embodiment, the gravitational direction is defined as the Z-axis direction, and the directions perpendicular to the Z-axis direction and mutually orthogonal are defined as the X-axis direction and the Y-axis direction, respectively. 1( a ) is a side view of the holding device 100 viewed from the X-axis direction, and FIG. 1( b ) is a cross-sectional view of the dotted line AA' shown in FIG. 1( a ) viewed from the Y-axis direction. The holding device 100 in this embodiment, as shown in FIG. 1(a) and FIG. 1(b), holds the optical element 1 such that the surface normal of the optical surface is relative to the gravitational force in the space defined by the Cartesian coordinate system. Orthogonal.

The holding device 100 has a base 2 , a fixing part 5 for fixing and holding the optical element 1 , a connecting part 13 (first holding part), a connecting part 10 (second holding part), and vibration sensors 20 , 21 , and 22 . The fixing part 5 is coupled to the base 2 via the connecting parts 10 and 13 . The fixing portion 5 is not necessarily configured, and the connection portions 10 and 13 may be directly connected to the optical element 1 . At least one of the connecting portion 10 and the connecting portion 13 is configured to be able to change the holding force of the base 2 holding the optical element 1 . That is, at least one of the connecting portion 10 and the connecting portion 13 has a rigidity adjusting means capable of changing the rigidity provided to the optical element 1 by the base 2 holding the optical element 1 .

As shown in FIG. 1( b ), in the fixed part 5, in order to measure the deformed shape of the optical element 1 vibrating at the natural frequency, vibration sensors 20 and 21 for detecting the vibration generated in the optical element 1 are provided. , 22 (vibration detection unit). FIG. 2 is a diagram illustrating in detail the arrangement positions of the vibration sensors 20 , 21 , and 22 in this embodiment. The vibration sensor 20 detects the vibration component of the Y-axis direction of the optical element 1, the vibration sensor 21 detects the vibration component of the X-axis direction of the optical element 1, and the vibration sensor 22 detects the vibration component of the Z-axis direction of the optical element 1. .

In the present embodiment, three vibration sensors 20 are provided in order to measure vibration components in the Y direction for each area of the optical element 1 . Accordingly, parallel vibration in the Y direction can be measured. In addition, the rotation component ωX around the X axis and the rotation component ωZ around the Z axis can be calculated from the vibration components respectively measured by the vibration sensors 20 , 21 , and 22 by a known method. In addition, the number and positions of the vibration sensors 20 , 21 , and 22 may be set arbitrarily based on the vibration components to be measured.

The configuration of the connecting portion 13 will be described in detail with reference to FIG. 3 . FIG. 3 is a diagram illustrating the configuration of the connection portion 13 in the holding device 100 . In the following description, although an example in which the connection part 13 has a rigidity adjustment means is described, the connection part 10 may have a rigidity adjustment means by having the same structure as the connection part 13 . In addition, only the connection part 10 may have rigidity adjustment means by the structure demonstrated below.

The connection part 13 has connection member 11a, 11b and the leaf spring 12 (rigidity adjustment means). The connecting member 11a fixes one part of the fixing portion 5, and is connected to the base 2 via the leaf spring 12 and the connecting member 11b. The connecting member 11b fixes two parts of the base 2 . The leaf spring 12 is arranged via the connection members 11 a and 11 b so as to bridge between the fixed portion 5 and the base 2 in the Y direction. The leaf spring 12 has a structure that can be changed even after the optical element 1 is arranged, and the holding force for holding the optical element 1 and the substrate 2 can be adjusted by changing the material, thickness, number, etc. of the leaf spring 12 .

In this embodiment, the coupling parts 10 and 13 hold the optical element 1 in a region not including the optical axis of the optical element 1 as shown in FIG. 1( a ). The optical axis passes through the center of the optical element 1, and the optical axis direction is a direction parallel to the Y-axis direction. In this embodiment, the base 2 and the fixing portion 5 are fixed via a plurality of connecting portions, and the connecting portion 10 holds the optical element 1 and the base 2 at a position different from the holding position where the connecting portion 13 holds the optical element 1 .

However, in the case of configuring a plurality of connection parts as in the present embodiment, if the holding force of each connection part to hold the optical element 1 is different, for example, the tilt ωX of the optical element 1 (wrapping around the optical element 1 and the optical element 1 The rotation of the X-axis in the direction perpendicular to the axis) produces a vibration mode.

The connecting parts 10 and 13 are configured so as not to generate a large rotational vibration mode that may affect the optical performance at the design stage. However, due to tolerances among the components of the holding device 100 or manufacturing errors in assembling the holding device 100 , there is a possibility that a rotational vibration mode larger than a design value may occur.

Regarding the rotational vibration mode, a rotational vibration mode is generated depending on the difference between the rigidity of the coupling part 10 holding the optical element 1 and the rigidity of the coupling part 13 holding the optical element 1 . For this reason, preferably, the connecting portion 10 and the connecting portion 13 are configured such that the difference between the holding force of the connecting portion 10 holding the optical element 1 and the holding force of the connecting portion 13 holding the optical element 1 is reduced. In this embodiment, at least one of the connection part 10 and the connection part 13 is configured so that the material, thickness, number, etc. can be changed after installation.

Next, an adjustment method for adjusting the rigidity adjustment means in this embodiment will be described. First, the vibration components are obtained through the vibration sensors 20 , 21 , 22 . From the vibration components acquired by the vibration sensors 20 , 21 , 22 , the rotational vibration mode is calculated. As a result of calculating the rotational vibration mode, for example, when a rotational vibration mode in the ωX direction is generated, it is considered that there is a difference between the holding force of the connecting portion 10 holding the optical element 1 and the holding force of the connecting portion 13 holding the optical element 1 .

Therefore, in this embodiment, the plate spring 12 is adjusted so that the difference between the holding force of the connecting portion 10 holding the optical element 1 and the holding force of the connecting portion 13 holding the optical element 1 is reduced. Specifically, when the holding force of the connecting portion 13 holding the optical element 1 is smaller than the holding force of the connecting portion 10 holding the optical element 1 , the material of the plate spring 12 is changed to a material with a small amount of deformation. Thereby, holding force can be improved. Alternatively, the retaining force can also be increased by increasing the thickness of the leaf spring 12 to reduce the amount of deformation, or by increasing the number of leaf springs 12 to reduce the amount of deformation to increase the retaining force.

By performing the above-mentioned adjustment, the vibration mode of the rotation of the optical element 1 can be reduced. More specifically, the rotational vibration mode of the optical element 1 can be converted into a parallel vibration mode. The parallel vibration mode of the optical element 1 is less sensitive than the rotational vibration mode. Therefore, the holding device 100 in this embodiment can suppress the reduction in optical performance.

<Second Embodiment> In the first embodiment, an example in which the rigidity adjusting means is a leaf spring has been described. In this embodiment, rigidity adjustment means other than leaf springs will be described. Referring to FIG. 4 , the holding device 200 for holding the optical element 1 will be described. FIG. 4( a ) and FIG. 4( b ) are diagrams illustrating the configuration of the holding device 200 according to this embodiment. In this embodiment, the gravitational direction is defined as the Z-axis direction, and the directions perpendicular to the Z-axis direction and mutually orthogonal are defined as the X-axis direction and the Y-axis direction, respectively. 4( a ) is a front view of the holding device 200 viewed from the Y-axis direction, and FIG. 4( b ) is a cross-sectional view of the dotted line BB' shown in FIG. 4( a ) viewed from the X-axis direction. The holding device 200 in this embodiment, as shown in Fig. 4(a) and Fig. 4(b), holds the optical element 1 in a space defined by a Cartesian coordinate system so that the surface normal of the optical surface is relative to the gravitational force. Orthogonal.

The holding device 200 has bases 2 a and 2 b , a coupling portion 16 (first holding portion) on which the optical element 1 is placed, a mounting portion 17 (second holding portion), and vibration sensors 20 , 21 , and 22 . The optical element 1 is held by the base 2 a via the mounting portion 17 . In addition, the optical element 1 is held by the base 2 b via the connecting portion 16 . At least one of the connecting portion 16 and the mounting portion 17 is configured to be able to change the holding force of the bases 2 a and 2 b holding the optical element 1 . That is, at least one of the connecting portion 16 and the mounting portion 17 has a rigidity adjusting means capable of changing the rigidity provided to the optical element 1 by changing the bases 2 a and 2 b holding the optical element 1 .

As shown in FIG. 4(a), on the back of the optical element 1, a vibration sensor 20 for detecting the vibration generated in the optical element 1 is provided in order to measure the deformed shape of the optical element 1 vibrating at a natural frequency. , 21, 22 (vibration detection part). The vibration sensor 20 detects the vibration component of the Y-axis direction of the optical element 1, the vibration sensor 21 detects the vibration component of the X-axis direction of the optical element 1, and the vibration sensor 22 detects the vibration component of the Z-axis direction of the optical element 1. .

The base 2b is configured to be mounted on the upper portion of the base 2a to cover the inside of the base 2a. The connection part 16 directly holds one part of the upper center of the optical element 1, is provided with a rigidity adjustment means, and is connected to the base 2b. The mounting portion 17 supports the weight of the optical element 1 at two lower locations in contact with the outer periphery of the optical element 1 at positions symmetrical with respect to a Y-Z plane formed by the optical axis (Y axis) and the Z axis. The mounting portion 17 is configured to sandwich the front and back of the optical element 1 so as to restrict the Y direction of the optical element 1 .

The configuration of the connecting portion 16 will be described in detail with reference to FIG. 5 . FIG. 5 is a diagram illustrating the configuration of the connection portion 16 in the holding device 200 . In the following description, although the connection part 16 has the rigidity adjustment means, the mounting part 17 may have the rigidity adjustment means by the same structure as the connection part 16. In addition, only the mounting part 17 may have rigidity adjustment means by the structure demonstrated below.

The connection part 16 has the connection member 14 and the bolt 15 (rigidity adjustment means). The bolts 15 fix the base 2b and the connecting portion 16 at a plurality of places. The bolt 15 has a configuration in which the arrangement, fastening torque, number, and the like of the bolt 15 can be changed even after the optical element 1 is arranged. The holding force for holding the optical element 1 and the base 2 b can be adjusted by changing the arrangement, tightening torque, number, etc. of the bolts 15 .

Although the optical element 1 and the base 2b are connected by the connecting member 14, since the optical element 1 is arranged such that the surface normal of the optical surface is perpendicular to the direction of gravity, it has a cantilever beam structure to support the upper part of the optical element 1. Such a configuration may cause a vibration mode in which the optical element 1 vibrates in the ωX direction.

The adjustment method for adjusting the rigidity adjusting means in this embodiment is similar to the first embodiment, and adjusts so that the rotational vibration mode is reduced based on the vibration components measured by the sensors 20 , 21 , and 22 . In the present embodiment, the bolt 15 is adjusted so that the difference between the holding force of the coupling portion 16 holding the optical element 1 and the holding force of the placing portion 17 holding the optical element 1 becomes small. Specifically, when the holding force of the connecting portion 16 holding the optical element 1 is smaller than the holding force of the placing portion 17 holding the optical element 1 , the holding force can be increased by increasing the number of bolts 15 . Alternatively, the holding force can be increased by increasing the tightening torque of the bolts 15 , or the holding force can be increased by reducing the amount of deformation by concentrating on the arrangement of the bolts 15 .

Therefore, by performing the above adjustment, the vibration mode of the rotation of the optical element 1 can be reduced. More specifically, the rotational vibration mode of the optical element 1 can be converted into a parallel vibration mode. The parallel vibration mode of the optical element 1 is less sensitive than the rotational vibration mode. Therefore, the holding device 200 in this embodiment can suppress the reduction in optical performance.

A modified example of this embodiment will be described with reference to FIG. 6 . 6( a ) and FIG. 6( b ) are diagrams illustrating the configuration of a holding device 300 according to a modified example of the present embodiment. 6( a ) is a front view of the holding device 300 viewed from the Y-axis direction, and FIG. 6( b ) is a cross-sectional view of the dotted line CC' shown in FIG. 6( a ) viewed from the X-axis direction. The holding device 200 in FIG. 4 is different in that it further has dynamic vibration absorbers 30 , 31 . The configuration other than the dynamic vibration reducers 30 and 31 is the same as that of the holding device 200 shown in FIG. 4 , so description thereof will be omitted.

The dynamic vibration reducers 30 and 31 can attenuate the high-order rotational vibration mode of the optical element 1 which was grasped in advance at the design stage. The dynamic vibration absorbers 30 and 31 are directly installed on the optical element 1, and two are arranged according to the vibration mode to be attenuated. For example, the dynamic vibration reducer 30 is arranged on the upper surface of the optical element 1 to attenuate the rotational vibration of the optical element 1 in the ωX direction. The dynamic vibration reducer 31 is arranged on the outer peripheral portion of the optical element 1 , and attenuates the rotational vibration of the optical element 1 in the ωZ direction.

By using the dynamic vibration absorbers 30 and 31, high-order rotational vibration components can be attenuated, but low-order vibration components due to tolerances in the components of the holding device 300 or manufacturing errors when the holding device 300 is assembled remain. vibrating ingredients. Therefore, high-order vibrations can be reduced through the dynamic vibration absorbers 30 and 31 , and low-order vibrations can be improved by adjusting the rigidity adjustment means to improve the deterioration of optical performance.

Therefore, by performing the above adjustment, the vibration mode of the rotation of the optical element 1 can be reduced. More specifically, the rotational vibration mode of the optical element 1 can be converted into a parallel vibration mode. The parallel vibration mode of the optical element 1 is less sensitive than the rotational vibration mode. Therefore, the holding device 300 in this embodiment can suppress the reduction in optical performance.

<Embodiments of Exposure Device> An embodiment in which the above-described holding devices 100 , 200 , and 300 are applied to an exposure device will be described with reference to FIG. 7 . FIG. 7 is a schematic diagram illustrating the configuration of the exposure apparatus EXP of the present embodiment. The exposure apparatus EXP has: an original stage 40 holding an original M (mask); a projection optical system PO projecting a pattern of the original M illuminated by an illumination optical system IL onto a substrate P; and a substrate stage 44 holding the substrate P. Exposure light irradiated from a light source not shown is condensed on the original plate M through the illumination optical system IL.

The projection optical system PO is an optical system for projecting a pattern formed on the original plate M onto a substrate P coated with a photosensitive material to transfer the pattern. In this embodiment, a projection optical system using an Offner type optical system is assumed. In the case of an Offner-type optical system, the original M is illuminated in an arc-shaped illumination area in order to secure a good image area. In addition, the irradiation shape of the exposure light which reaches the board|substrate P also becomes an arc shape. The unillustrated light source is, for example, a high-pressure mercury lamp or a light source using an LED.

The light irradiated from the light source passes through the illumination optical system IL and the original plate M, and after being reflected by the trapezoidal mirror 41, the concave mirror 42, the convex mirror 43, the concave mirror 42, and the trapezoidal mirror 41 in turn, reaches the substrate P, and the pattern on the original plate M is transferred to the substrate P superior. The convex mirror 43 is held, for example, by the holding device 100 described in the first embodiment.

In addition, since the concave mirror 42 is larger than the convex mirror 43, it is preferable to hold it more stably than the holding device 100 in the first embodiment. For this reason, it is preferable to have a configuration that can support the bottom surface of the optical element, like the holding device 200 in the second embodiment, so that the self-weight of the concave mirror 42 can be supported. For this purpose, the concave mirror 42 is held, for example, through the holding device 200 described in the second embodiment.

In the above-mentioned example, the example in which at least one optical element of the projection optical system PO is held by the holding device 100 or the holding device 200 has been described, but it is not limited thereto. At least one optical element in the optical system IL.

By holding the concave mirror 42 and the convex mirror 43 in the exposure device EXP by the holding device related to the present invention, the vibration mode of rotation can be reduced even after the exposure device EXP is installed. Therefore, the exposure process using the exposure apparatus EXP can suppress the reduction of exposure performance, and thus is advantageous in at least one of article performance, quality, productivity, and production cost compared to conventional methods.

<Embodiments of the manufacturing method of the article> The manufacturing method of the article concerning embodiment of this invention is suitable for manufacturing a flat panel display (FPD), for example. The manufacturing method of the article according to this embodiment includes: forming a latent image pattern on the photosensitive agent coated on the substrate through exposure using the above-mentioned exposure device to obtain an exposed substrate (exposure process); A process of developing the exposed substrate on which the latent image pattern is formed to obtain a developed substrate (development process). Furthermore, the manufacturing method includes other well-known procedures (oxidation, film formation, vapor deposition, doping, planarization, etching, resist stripping, dicing, bonding, packaging, etc.). The method of manufacturing an article according to this embodiment is advantageous in at least one of article performance, quality, productivity, and production cost compared to conventional methods.

As mentioned above, although the preferred embodiment of this invention was described, it goes without saying that this invention is not limited to these embodiment, Various deformation|transformation and a change are possible within the range of the summary.

According to the present invention, it is possible to provide a holding device which is advantageous in order to suppress a decrease in optical performance.

1: Optical components 2: base 10: Connecting part (second holding part) 12: Leaf spring (rigid adjustment means) 13: Connecting part (1st holding part) 100: holding device

[ Fig. 1 ] A schematic diagram illustrating the configuration of a holding device in a first embodiment. [ Fig. 2 ] A diagram for explaining a configuration of a vibration sensor. [ Fig. 3 ] A diagram for explaining rigidity adjusting means in the first embodiment. [ Fig. 4 ] A schematic diagram illustrating the configuration of a holding device in a second embodiment. [ Fig. 5 ] A diagram for explaining a rigidity adjusting means in a second embodiment. [ Fig. 6 ] A schematic diagram illustrating a modification of the holding device in the second embodiment. [FIG. 7] It is a schematic diagram which shows the structure of an exposure apparatus.

1: Optical components

2: base

5: fixed part

11a, 11b: Connecting components

12: leaf spring (rigid adjustment means)

13: Connecting part (1st holding part)

Claims (18)

a holding device, holding the optical element, have: base; a first holding unit that holds the aforementioned optical element and the aforementioned base; and a second holding portion holding the optical element and the substrate at a position different from the holding position where the first holding portion holds the optical element; It is configured so that the rigidity of at least one of the first holding portion and the second holding portion can be changed. The holding device according to claim 1, which further has a fixing portion for fixing and holding the aforementioned optical element, The first holding portion and the second holding portion hold the optical element and the base via the fixing portion. The holding device according to claim 1, wherein at least one of the first holding portion and the second holding portion is configured to reduce the holding force of the substrate holding the optical element via the first holding portion and the substrate The difference in holding force of the optical element is held via the second holding portion. The holding device according to claim 1, wherein the first holding portion and the second holding portion hold the optical element in a region excluding the optical axis of the optical element. The holding device according to claim 1, further comprising a detection unit for detecting vibration generated in the optical element. The holding device according to claim 1, wherein at least one of the first holding portion and the second holding portion is configured to change the rigidity imparted to the optical element by holding the optical element on the base. The holding device according to claim 6, wherein at least one of the first holding portion and the second holding portion has a rigidity adjusting means capable of adjusting the rigidity. The holding device according to claim 7, wherein the aforementioned rigidity adjustment means includes a leaf spring. The holding device according to claim 7, wherein the aforementioned rigidity adjusting means comprises bolts. The holding device according to claim 1, wherein at least one of the first holding portion and the second holding portion can be adjusted to a vibration mode capable of reducing rotation generated in the optical element. The holding device according to claim 1, wherein at least one of the first holding portion and the second holding portion can be adjusted to convert a rotational vibration mode generated in the optical element into a parallel vibration mode. The holding device according to claim 11, wherein the vibration mode of the rotation is vibration in a direction of rotation about an axis perpendicular to the optical axis of the optical element. The holding device according to claim 11, wherein the aforesaid concurrent vibration mode is vibration along the direction of the optical axis of the aforesaid optical element. An adjustment method, in a holding device that holds an optical element through a base through a first holding portion and a second holding portion, adjusting the holding force of the base to hold the optical element, Include: A test procedure for detecting vibrations generated in the aforementioned optical components; and Based on the result detected by the detection program, the program for adjusting the rigidity of at least one of the first holding portion and the second holding portion is changed. The adjustment method according to claim 14, wherein, in the adjustment procedure, based on the results detected in the detection procedure, the holding force of the optical element is held by the substrate via the first holding part and the holding force of the optical element is held by the substrate via the second holding part. At least one of the first holding portion and the second holding portion is adjusted so that the difference in holding force for holding the optical element decreases. The adjustment method according to claim 14, wherein in the adjustment procedure, the rotational vibration mode generated in the optical element is reduced based on the result detected in the detection procedure. An exposure device for exposing the above-mentioned photosensitive material in such a manner that a pattern formed on an original plate is transferred to a photosensitive material coated on a substrate using exposure light from a light source, have: an illumination optical system that illuminates the exposure light from the aforementioned light source on the aforementioned original plate; and a projection optical system, which projects the exposure light transmitted through the original plate onto the substrate; At least one optical element included in the illumination optical system and the projection optical system is held by the holding device according to claim 1. a method of manufacture of an article, Include: Exposing the substrate by using the exposure device according to claim 17 to obtain an exposure program for exposing the substrate; and Developing the aforementioned exposed substrate to obtain a developing procedure for developing the substrate; Articles were fabricated from the aforementioned developed substrates.

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