Optical component, method of mounting optical component, and projection exposure apparatus

Abstract

An optical component (200) for EUV lithography, comprising a media delivery pipe system (300, 307, 400, 406, 500, 508) operating in a vacuum environment, where the media delivery pipe system (300, 307, 400, 406, 500, 508) comprises at least one connection region (209) between a metal section (207) and a section (205) made of a silicon-containing substrate material having a linear expansion coefficient of less than 3 ppm / K, characterized in that the metal section (207) and the section (205) are made of a silicon-containing substrate material having a linear expansion coefficient of less than 3 ppm / K. The connection region (209) is at least partially surrounded by an externally adjoining sealing device (210), where the sealing device (210) comprises a sealing element (211) and a fixing device (212) attaching the sealing element (211) to the connection region (209), and where the sealing element comprises an elastomer.

Description

TECHNICAL FIELD

[0001] The invention relates to an optical component for an EUV projection exposure apparatus, comprising a media supply tube system for operation in a vacuum environment, wherein the media supply tube system has at least one connection region between two sections, and wherein the connection region is at least partially surrounded by an externally adjoining sealing device.

[0002] The invention also relates to an EUV projection exposure apparatus having at least one optical component and a method of mounting an optical component. BACKGROUND

[0003] Projection exposure apparatuses for EUV lithography are used for manufacturing microstructured or nanostructured devices in microelectronics or microsystems technology. In order to be able to precisely manufacture structures having extremely small dimensions in the nanometer and micrometer range, the respective projection exposure apparatus must be able to precisely image the structures contained on a reticle onto a substrate, for example a wafer.

[0004] In the design of projection exposure apparatuses for the EUV range, a wavelength of 13.5 nm is usually used in order to achieve the respective resolution on the substrate. Due to the lack of suitable light-transmissive materials in this wavelength range, mirrors are used as optical components for the imaging process. Since all gases have a low transmissivity at wavelengths in the 13.5 nm range, it is necessary to operate projection exposure apparatuses designed in this way in a vacuum environment.

[0005] Due to the resolution required of EUV projection exposure apparatuses, it is also necessary for the optical components of the EUV projection exposure apparatus to exhibit as little temperature-dependent change in length as possible, as a result of which, if possible, no or only slight deformations, in particular of the optical surfaces, occur during operation. For this purpose, substrate materials having a very small coefficient of linear expansion at the operating temperature are used for the optical components. Thus, for example, quartz glass, titanium-doped quartz glass or SiSiC are used as substrate materials.

[0006] In order to operate the optical components as stably as possible at the operating temperature, they can be designed to be temperature-controllable. In this regard, reference is made to the document DE 10 2017 221 388 A1, which describes how cooling structures in the optical components can be obtained from the described substrate materials. These cooling structures have connections, which are formed from the same substrate material as the mirror substrate itself. In order to be connected to an external media supply, these connections are connected to further tube sections. Usually, such external media supplies are made of a metallic material, in particular stainless steel, aluminum, nickel, copper or alloys thereof.

[0007] Therefore, internal sealing systems for connecting different pipe sections via flange surfaces are known from the prior art, for example. References DE102022203254B3, DE102020208496A1, and DE102020208200A1. If such flange-based connections are not possible due to design limitations, the substrate material of the optical components (such as quartz glass, titanium-doped quartz glass, or SiSiC) must be directly bonded (particularly by welding, brazing, bonding, or clamping) to a metallic material (such as stainless steel, aluminum, nickel, copper, or alloys thereof).

[0008] However, external influences (such as during installation or operation) can cause leakage at the interface or joint area of ​​this direct connection between the substrate material and the metal material. This is particularly true for components that are welded, brazed, or bonded, where there are fixed connections that cannot be opened non-destructively. To achieve this, repairs must be performed by removing the leak and reapplying the weld, brazed, or bonded joint. This repair process is typically very time-consuming and associated with high costs. There is also a risk that the defect pattern cannot be eliminated through repair. Even if repairs are successful, the leak may recur in subsequent processes if the cause is unknown. Furthermore, if such leakage occurs in an EUV projection exposure apparatus during operation, there is a risk of significant damage to the EUV projection exposure apparatus due to operation in a vacuum environment.

[0009] Therefore, the object of the present invention is to provide an improved optical component for an EUV projection exposure apparatus and a method for mounting the same, which avoids the disadvantages described in the prior art and is suitable for operation in a vacuum environment.

[0010] This objective is achieved according to the features of the independent claim. Summary of the Invention

[0011] The optical component for EUV lithography according to the invention has a dielectric delivery tube system for operation in a vacuum environment, wherein the dielectric delivery tube system includes at least one connection region between a metal section and a section made of a silicon-containing substrate material with a linear coefficient of thermal expansion of less than 3 ppm / K. The connection region is at least partially surrounded by an externally adjacent sealing device, wherein the sealing device includes a sealing element and a fixing means for attaching the sealing element to the connection region, and wherein the sealing element includes an elastomer.

[0012] The sealing device successfully eliminates existing and potential leaks in the connection area. Such sealing devices are known from the prior art in cases of repairing leaks in one-piece metal piping systems (see, for example, WO15050428A1). The inventors have recognized that this sealing device can be transferred to a media delivery piping system for optical components having a connection area between a metal section and a section made of a silicon-containing substrate material with a linear expansion coefficient of less than 3 ppm / K. Surprisingly, it can also be shown that the sealing device is suitable for the vacuum environment required for operating EUV lithography optical components, particularly the EUV plasma environment. Specifically, the media delivery piping system refers to, but is not limited to, piping systems with circular, square, or triangular cross-sections.

[0013] According to a first embodiment of the optical component, the sealing device includes a shielding unit. For example, the shielding unit is made of a metallic material, particularly aluminum, copper, or stainless steel. Here, the shielding unit may surround the sealing element and the fixing device, whereby the fixing device is used to directly attach the sealing element to the connection area. Similarly, the shielding unit may be arranged between the sealing element and the fixing device. In particular, if the shielding unit is designed in the form of a foil, a more stable attachment can be achieved through this arrangement, because in this case the fixing device also serves to attach the shielding unit.

[0014] Shielding units improve the usability of sealing devices in vacuum and / or EUV plasma environments within EUV projection exposure equipment by encapsulating sealing elements or sealing elements and fixtures. This may be particularly necessary in areas of EUV projection exposure equipment with very high cleanliness requirements and / or EUV plasma densities. Using shielding units advantageously prevents or minimizes degassing and potential interactions with EUV-induced plasmas within the sealing device.

[0015] According to one embodiment of the optical component, the sealing device has a mirror axis parallel to the connection area. This provides a symmetrical design because the two connection segments are mirror images of each other within the connection area. The symmetrical design results in improved ease of installation, as the sealing element can be installed in a torsionally fixed manner. More uniform compressibility of the sealing element relative to the connection area is also achieved.

[0016] According to one embodiment of the optical component, the medium delivery pipe system is a water delivery pipe system for temperature control of the optical component. For optimal imaging characteristics, it is necessary for the substrate material of the optical component according to the invention to have the smallest possible length change during operation. To this end, the substrate material used for the optical component has an extremely small coefficient of linear expansion at the operating temperature. The water delivery pipe system achieves particularly effective temperature control of the optical component, especially over the operating temperature range.

[0017] According to an alternative embodiment of the optical component, the media delivery system is a gas delivery system. Therefore, a purge gas, such as nitrogen or hydrogen, can contact various areas of the optical component. The desired cleanliness can be provided and achieved by purging within the package volume of the optical component. Alternatively, the purge gas can also be used for temperature control.

[0018] According to particularly advantageous embodiments of the optical components, the connection area has an interface for welding, brazing, bonding, or clamping. These bonding techniques are particularly suitable for bonding metal and silicon-containing substrate materials.

[0019] According to another embodiment of the optical component, the metal section includes stainless steel, aluminum, nickel, or copper. These materials are particularly suitable for forming media delivery tube systems and can be obtained in a variety of ways. For example, they are characterized by high resistance to the media used, especially corrosion resistance. They also have low degassing and high resistance to EUV plasma environments, which is advantageous for use in vacuum environments. Furthermore, the material is easy to clean, and therefore can be obtained with a correspondingly good cleanliness quality.

[0020] According to one embodiment of the optical component, the segment composed of a silicon-containing substrate material includes quartz glass, titanium-doped quartz glass, or SiSiC. These materials are particularly suitable as substrate materials for optical components used in EUV lithography. They sometimes have extremely low coefficients of linear expansion within the operating temperature range of the optical component. Furthermore, these substrates can be coated with various materials to achieve reflectivity for EUV radiation.

[0021] According to particularly advantageous embodiments of the optical components, the sealing element comprises a fluoropolymer, such as fluororubber or perfluororubber. These fluoropolymers are characterized by good temperature resistance and are suitable for applications involving contact with corrosive media and / or requiring high purity. Similarly, the sealing element may be made of nitrile rubber, ethylene propylene diene rubber, or tetrafluoroethylene hexafluoropropylene copolymer.

[0022] According to one embodiment of the optical component, the fixing device includes a stainless steel clamp. The clamp is designed so that the sealing element is uniformly compressed at the connection area. The clamp is particularly suitable for circular pipe geometries. The use of stainless steel makes the clamp suitable for use in vacuum environments and easy to clean.

[0023] According to a particularly advantageous embodiment of the optical component, the clamp has open threads for screw connection. Open threads refer to a combination of threads and slots separated at the two connectors of the clamp, resulting in the screws used to attach the clamp being fully removable, thus creating a gap between the connectors when the clamp is opened. This causes the threads to open when the screw is removed. Consequently, cleanliness is further improved, in particular. Alternatively, an ear hose clamp can be used.

[0024] Furthermore, the present invention relates to a projection exposure apparatus for EUV lithography, having at least one optical component as described in claims 1-11.

[0025] This leads to the advantages already mentioned for the projection exposure apparatus according to the invention. Other advantages and preferred features will be apparent from the foregoing description and claims.

[0026] Furthermore, the present invention relates to a method for installing a sealing device for the connection area between a metal section of a media delivery tube system for optical components used in a vacuum environment and a section made of a silicon-containing substrate material with a linear expansion coefficient of less than 3 ppm / K.

[0027] In the first step of this method, an mounting cone is provided at the open end of the first section. The mounting cone allows the diameter difference between the sealing element and the first section of the media delivery piping system to be bridged. Advantageously, the mounting cone is placed on the section with the smaller diameter of the two sections, so that the diameter difference to be bridged is as small as possible. The mounting cone can be made of, for example, stainless steel or aluminum alloy, and plastics such as polyoxymethylene (POM) or polyetheretherketone (PEEK).

[0028] In the second step of the method, a sealing element is provided. The sealing element is made of, for example, fluororubber or perfluororubber. Similarly, the sealing element can be made of nitrile rubber, ethylene propylene diene rubber, or tetrafluoroethylene hexafluoropropylene copolymer.

[0029] In the third step of the method, the sealing element is placed on the mounting cone at the open end of the first section.

[0030] In the fourth step of the method, the sealing element is stretched and fitted onto the first segment, wherein the sealing element moves to and surrounds the connection area. Since the resilient sealing element used for installation by means of the mounting cone has bridged the diameter difference relative to the first segment if necessary, the sealing element can abut against and surround the connection area.

[0031] In the fifth step of the method, a fixing device is provided. The fixing device may include a clamp made of stainless steel. Preferably, the clamp has open threads depending on the application, which results in easier cleaning.

[0032] In the sixth step of the method, the fixing device is attached to the sealing element such that the fixing device at least partially surrounds and compresses the sealing element to obtain a sealing device.

[0033] According to one embodiment of the method of the invention, a shielding unit is provided in the seventh step. The shielding unit is made of, for example, aluminum, copper, or stainless steel. Similarly, the shielding unit can be designed in the form of a foil, resulting in a more flexible fit to the sealing element. Subsequently, in the eighth step, the shielding unit is attached to the sealing device such that the shielding unit at least partially, and particularly completely, surrounds the sealing device. The shielding unit improves the usability of the sealing device and optical components in the vacuum environment and / or EUV plasma environment within the projection exposure apparatus by at least partially encapsulating the sealing element and the fixing device. This prevents or minimizes degassing and possible interactions with EUV-induced plasma of the sealing device.

[0034] In an alternative embodiment of the method according to the invention, a shielding unit is provided after the fourth step (stretching the sealing element), and the shielding unit is attached to the sealing element such that the shielding unit at least partially, and particularly completely, surrounds the sealing element. A fixing device is then provided according to the fifth step, and in an alternative step, the fixing device is attached to the shielding unit and the sealing element below. In particular, if the shielding unit is designed in the form of a foil, this embodiment of the method allows for a more stable attachment, because in this case the fixing device also serves to attach the shielding unit. Attached Figure Description

[0035] The present invention will now be described in detail with reference to the accompanying drawings.

[0036] In the attached diagram:

[0037] Figure 1 Display EUV projection exposure equipment

[0038] Figure 2 This invention displays the optical components used in a projection exposure apparatus.

[0039] Figure 3a and 3b A media delivery pipe system for an optical component is shown, which has a vacuum-compatible symmetrical sealing device for the connection area of ​​the pipe system.

[0040] Figure 4a and 4b A media delivery pipe system for an optical component is shown, which has a vacuum-compatible asymmetric sealing device for the connection area of ​​the pipe system.

[0041] Figure 5a and 5b A media delivery pipe system for an optical component is shown, which has a vacuum-compatible symmetrical sealing device including a shielding unit for the connection area of ​​the pipe system.

[0042] Figure 6a and 6bThe method steps for installing a sealing element as a component of a sealing device for a media delivery pipeline system are shown.

[0043] Figure 7 A flowchart illustrating an embodiment of the method of the present invention is shown.

[0044] Figure 8 A clamp is shown as a fixing element for attaching a sealing element to a connection area having an open thread for threaded connection. Detailed Implementation

[0045] Figure 1 The basic structure of an EUV projection exposure apparatus 100 for semiconductor lithography is shown as an example.

[0046] The illumination system 101 of the EUV projection exposure apparatus 100, in addition to the radiation source 102, includes an illumination optics unit 103 for illuminating the object field 104 in the object plane 105. A mask master 106, disposed in the object field 104, is illuminated and held by a mask master holder 107, a portion of which is schematically shown. The projection optics unit 108 is used to image the object field 104 onto an image field 109 in the image plane 110. The structure on the mask master 106 is imaged onto the photosensitive layer of a wafer 111, which is disposed in the region of the image field 109 in the image plane 110 and held by a wafer holder 112, also partially shown.

[0047] The radiation source 102 emits EUV radiation 113, particularly in the range of 5 nm to 30 nm, especially 13.5 nm. For this purpose, the radiation source has a concentrator mirror 126 as an optical component. Optically designed and mechanically adjustable optical elements are used to control the radiation path of the EUV radiation 113. Figure 1 In the case of the EUV projection exposure apparatus 100 shown, the optical element is in the form of an adjustable mirror, as mentioned below only as an example in a suitable embodiment. The individual element in the form of a mirror may here consist of multiple segments having mutually separated optical surface portions.

[0048] EUV radiation 113 generated by radiation source 102 is aligned by a concentrator mirror 126 integrated in radiation source 102, such that EUV radiation 113 passes through the central focal point in the region of the intermediate focal plane 114 before incident on field plane mirror 115. Downstream of field plane mirror 115, EUV radiation 113 is reflected by pupil plane mirror 116. By means of pupil plane mirror 116 and other optical components 117, 118, 119, the field plane of field plane mirror 115 is imaged into object field 104. See US9411241B2 accordingly.

[0049] The mask master 106 arranged in the object field 104 may be, for example, a reflective light mask having reflective and non-reflective, or at least less reflective, regions for generating at least one structure on the mask master 106. Alternatively, the mask master 106 may be a plurality of micromirrors arranged in one-dimensional or multi-dimensional components and optionally movable about at least one axis to set the angle of incidence of EUV radiation on the respective mirrors.

[0050] The mask master 106 reflects some beam paths of the illumination optics unit 103 and shapes beam paths in the projection optics unit 108. These beam paths transmit information to the projection optics unit 108 via the structure of the mask master 106, which generates an image representation of the mask master 106 or a corresponding portion thereof on the wafer 111 arranged in the image plane 110. The wafer comprises a semiconductor material, such as silicon, and is arranged on a wafer holder 112, also known as a wafer stage.

[0051] In this example, the projection lens 108 has six reflective optical elements 120 to 125, which are in the form of mirrors, to produce an image of the mask master 106 on the wafer 111. The number of mirrors in the projection lens 108 is typically between four and eight; however, alternatively, only two mirrors or even ten mirrors may be used. Projection lenses are known from US2016 / 0327868A1 and DE102018207277A1.

[0052] Figure 2 This shows an optical component 200 for the projection exposure device 100, which, for example, corresponds to... Figure 1 The optical components 115–119 and 120–126 described herein. In this case, the optical component 200 is designed in the form of a mirror, comprising a mirror substrate 201 to which a reflective surface 202 has been applied. Quartz glass, titanium-doped quartz glass, or SiSiC is used as the substrate material, typically characterized by a linear coefficient of thermal expansion of less than 3 ppm / K. This achieves sufficiently good dimensional stability, particularly within the operating temperature range of the optical component 200. The mirror substrate 201 can be temperature-controlled so that the operating temperature remains stable even under the high power density of EUV radiation 113. For this purpose, the mirror substrate 201 includes a channel 203 through which a medium can flow. Gaseous and liquid substances can be used as the medium, particularly a cooling medium. To deliver the medium in a targeted manner, the channel 203 has an inlet 204 and an outlet 205. In this case, the input element 204 and the output element 205 are formed of the same material as the reflector substrate 201, such as quartz glass, titanium-doped quartz glass, or SiSiC.

[0053] To connect the temperature-controlled reflector substrate 201 to an external media supply device via input 204 and output 205, input 204 and output 205 are connected to metal tube sections 206 and 207. Metal tube section 206 is designed as a feed section, and metal tube section 207 is designed as a discharge section for possible media delivery (see arrow direction), and is made of, for example, stainless steel, aluminum, nickel, copper, or alloys thereof. For connection, connection regions 208 and 209 are formed between input 204 and metal tube section 206, and between output 205 and metal tube section 207. For example, input 204 and / or output 205 are welded, brazed, or bonded to metal sections 206 or 207. Such a device is known, for example, from DE102017221388A1.

[0054] However, there is a risk that the connection areas 208 and / or 209 may be damaged or leaked, for example, due to corrosion, during operation or installation. Since the optical components 200 typically operate in a vacuum environment, the vacuum will be affected.

[0055] Therefore, a sealing device 210, which at least partially surrounds the externally adjacent connection region 209, is mounted on the connection region 209. The sealing device 210 includes a sealing element 211 and a fixing device 212; the sealing element 211 includes an elastomer. Because... Figure 2 This is a perspective cross-sectional view of the connection region 209, and the sealing device 210 is rotationally symmetrical around the connection region 209, so the elements 211 and 212 of the sealing device 210 are shown on the left and right sides of the connection region 209.

[0056] The sealing element 211 is compressed by the retaining device 212 at the connection region 209, and in this case, at least surrounds the leakage area or potential leakage area of ​​the connection region 209. In this case, the sealing element 211 is at least partially encapsulated relative to the environment by the retaining device 212. Therefore, the potential free area of ​​the sealing element 211 must be suitable for vacuum environments, and particularly EUV plasma environments. Therefore, the sealing element 211 is made of, for example, fluororubber or perfluororubber. Similarly, the sealing element 211 can be made of nitrile rubber, ethylene propylene diene rubber, or tetrafluoroethylene hexafluoropropylene copolymer. The retaining device 212 can be designed as a clamp and made of stainless steel. Preferably, the clamp has open threads depending on the application, resulting in easier cleaning.

[0057] In the following, Figures 3-5 illustrate various exemplary embodiments of a dielectric delivery tube system according to the present invention, which includes a metal section, a section made of a silicon-containing substrate material with a linear expansion coefficient of less than 3 ppm / K, a connection region, and a sealing device at least partially surrounding the connection region. Exemplary embodiments are part of an optical component for operation in the vacuum environment of EUV lithography, for example, according to... Figure 2 For clarity, it has not been shown separately again.

[0058] Figure 3a and 3b Two embodiments 300 and 307 of a media delivery tube system for optical components operating in a vacuum environment, having sealing devices 314 and 315, are shown. Metal tube sections 302 and 309 are connected, for example by welding, brazing, bonding, or clamping, to tube sections 301 and 308 made of a silicon-containing substrate material having a coefficient of linear expansion of less than 3 ppm / K, respectively, via connection regions 303 and 310. Connection regions 303 and 310 are at least partially surrounded by externally adjacent sealing devices 314 and 315, wherein sealing devices 314 and 315 include sealing elements 304 and 311 and fixing devices 305 and 312. In this case, sealing elements 304 and 311 are attached to connection regions 303 and 310 by fixing devices 305 and 312. For the best possible sealing effect, the shapes of sealing elements 304 and 311 are adapted to the environment of connection regions 303 and 310, respectively. Regarding the possible materials for the two connecting sections 301, 302, 308, 309, the sealing elements 304, 311, and the fixing devices 305, 312, according to Figure 2 The examples described apply similarly.

[0059] according to Figure 3a and Figure 3b Embodiments 300 and 307 are characterized by a symmetrical design, which in each case is manifested by mirror axes 306 and 313 within the sealing devices 314 and 315 parallel to the connecting regions 303 and 310. The advantage of the symmetrical design is that it improves the ease of installation and ensures that the compression of the sealing elements 304 and 311 relative to the connecting regions 303 and 310 is as uniform as possible.

[0060] Figure 4a and 4bTwo further embodiments 400 and 406 of a media delivery tube system for optical components operating in a vacuum environment, having sealing devices 414 and 415, are shown. Metal sections 402 and 408 are connected, for example by welding, brazing, bonding, or clamping, to sections 401 and 407 made of a silicon-containing substrate material with a linear expansion coefficient of less than 3 ppm / K, respectively, via connection regions 403 and 409. Connection regions 403 and 409 are at least partially surrounded by externally adjacent sealing devices 414 and 415, wherein sealing devices 414 and 415 include sealing elements 404 and 410 and fixing devices 405 and 411. In this case, sealing elements 404 and 410 are attached to connection regions 403 and 409 via fixing devices 405 and 411. Regarding the possible materials of the two connection sections 401, 402, 407, and 408, sealing elements 404 and 410, and fixing devices 405 and 411, [further details are needed]. Figure 2 The examples described apply similarly.

[0061] according to Figure 4a and 4b The embodiments 400 and 406 are characterized by an asymmetrical design of the sealing devices 414 and 415, which in each case manifests as the absence of a mirror axis parallel to the connecting region 403 or 409 within the sealing devices 414 and 415. If an asymmetrical design is chosen due to the geometry of the sections to be connected, the sealing elements 404 and 410 may have special markings to improve ease of installation. For the best possible sealing effect, the shape of the sealing elements 404 and 410 for the asymmetrical design is also adapted to the environment of the connecting regions 403 and 409 in each case. To better position and support the sealing element 410 on the section 407 and the fixing device 411, as Figure 4b As shown, it can include individually fitted web plates 412 and 413.

[0062] Figure 5a and 5bTwo additional embodiments 500 and 508 of a media delivery tube system for optical components operating in a vacuum environment, having sealing devices 516 and 517, are shown. Metal sections 502 and 510 are connected, for example by welding, brazing, bonding, or clamping, to sections 501 and 509 made of a silicon-containing substrate material with a linear expansion coefficient of less than 3 ppm / K, respectively, via connection regions 503 and 511. In this case, these embodiments 500 and 508 have a symmetrical design, which in each case is manifested by mirror axes 506 and 514 within the sealing devices 516 and 517 parallel to the connection regions 503 and 511. The connection regions 503 and 511 are at least partially surrounded by externally adjacent sealing devices 516 and 517, respectively, wherein the sealing devices 516 and 517 include sealing elements 504 and 512 and fixing devices 505 and 513. In this case, sealing elements 504 and 512 are attached to connection areas 503 and 511 by means of fixing devices 505 and 513.

[0063] Apart from Figure 3a , Figure 3b , Figure 4a and Figure 4b In addition to the embodiments described above, embodiments 500 and 508 each have shielding units 507 and 515, respectively. Figure 5a The shielding unit 507 may surround the sealing element 504 and the fixing device 505, resulting in the fixing device 505 functioning to directly attach the sealing element 504 at the connection area 503. Similarly, as Figure 5b As shown, the shielding unit 515 can be arranged between the sealing element 512 and the fixing device 513. In particular, if the shielding unit 515 is designed in the form of a foil, a more stable attachment can be achieved through this component, because the fixing device 513 also has the attachment effect for the shielding unit 515 in this case.

[0064] Shielding units 507 and 515 improve the usability of sealing devices 516 and 517 in the vacuum and / or EUV plasma environment within the projection exposure apparatus 100 by encapsulating sealing elements or sealing elements and fixing devices. This may be particularly necessary in areas of the projection exposure apparatus 100 with very high cleanliness requirements and / or EUV plasma densities. Using shielding units 507 and 515 prevents or minimizes degassing and possible interactions with EUV-induced plasma from sealing devices 516 and 517. For this purpose, shielding units 507 and 515 are made of, for example, aluminum, copper, or stainless steel. The use of shielding units is also possible for asymmetric designs.

[0065] To achieve the best possible sealing effect, the shapes of sealing elements 504 and 512 are adapted to the environments of connection areas 503 and 511, respectively. Regarding the possible materials for the two connection sections 501, 502, 509, and 510, sealing elements 504 and 512, and fixing devices 505 and 513, [the following is considered]. Figure 2 The examples described apply similarly.

[0066] Figure 6a and 6b Two method steps for mounting a sealing element 604, which is a component of a sealing device 210 for a media delivery system 600 for optical components, are shown. In this case, the media delivery system 600 according to the invention includes a metal section 602 and a section 601 made of a silicon-containing substrate material having a coefficient of linear expansion of less than 3 ppm / K, which are connected by a connection region 603, for example by welding, brazing, bonding, or clamping. Since the media delivery system 600 is designed to operate in a vacuum environment, and the connection region 603 is at risk of leakage during operation or during installation in preparation for operation, the connection region 603 of the media delivery system 600 is intended to be additionally protected by a sealing device.

[0067] For this purpose, such as Figure 6a As shown, a sealing element 604, typically made of an elastomer, is guided on a first section 601 of the media delivery piping system 600 by means of a mounting cone 605. Advantageously, this begins with a pipe section of smaller diameter. In this case, the mounting cone 605 allows the inner diameter d1 of the sealing element 604 to continuously expand to an extended inner diameter d2. When the extended inner diameter d2 is reached, the mounting cone is removed in the direction of the pipe section 601 with the smaller inner diameter. Figure 6b As shown, the thus expanded sealing element 604 can be stretched and fitted onto the first section 601, wherein the sealing element 604 moves in the direction of the arrow to the connection region 603. Here, the sealing element 604 can be attached to the connection region 603 by means of a fixing device and, if necessary, a shielding unit (both not shown).

[0068] Figure 7 A flowchart illustrating an embodiment of the method of the present invention for mounting sealing devices 210, 314, 315, 414, 415, 516, and 517 for mounting media delivery tube systems 300, 307, 400, 406, 500, 508, and 600 to form the optical component 200 of the present invention is shown. The method is described with reference to the illustrated media delivery tube systems 300, 307, 400, 406, 500, and 508 of the optical component 200, and is applicable to the optical component 200.

[0069] In the first step S1, a mounting cone 605 is provided at the open end of the first section 601. The mounting cone 605 enables bridging of the diameter difference between the sealing elements 211, 304, 311, 404, 410, 504, 512, 604 and the first section of the media delivery pipe system 300, 307, 400, 406, 500, 508, 600. Advantageously, the mounting cone 605 is placed on the section with the smaller diameter of the two sections, so that the diameter difference to be bridged is as small as possible.

[0070] In the second step S2, sealing elements 211, 304, 311, 404, 410, 504, 512, and 604 are provided. Sealing elements 211, 304, 311, 404, 410, 504, 512, and 604 comprise elastomers, such as fluororubber or perfluororubber. Similarly, sealing elements 211, 304, 311, 404, 410, 504, 512, and 604 may comprise nitrile rubber, ethylene propylene diene rubber, or tetrafluoroethylene hexafluoropropylene copolymer.

[0071] In the third step S3, sealing elements 211, 304, 311, 404, 410, 504, 512, and 604 are placed on the mounting cone 605 at the open end of the first section 601.

[0072] In the fourth step S4, sealing elements 211, 304, 311, 404, 410, 504, 512, and 604 are stretched and fitted onto the first segment 601 and moved to the connecting areas 209, 303, 310, 403, 409, 503, 511, and 603 to surround it. As the resilient sealing elements 211, 304, 311, 404, 410, 504, 512, and 604 used for installation expand from the inner diameter d1 to the inner diameter d2 through the mounting cone 605, the sealing elements 211, 304, 311, 404, 410, 504, 512, and 604 rest against and surround the connection areas 209, 303, 310, 403, 409, 503, 511, and 603.

[0073] In the fifth step S5, fixing devices 212, 305, 312, 405, 411, 505, and 513 are provided. Fixing devices 212, 305, 312, 405, 411, 505, and 513 may include stainless steel clamps. Preferably, the clamps have open threads depending on the application, resulting in easier cleaning.

[0074] In the sixth step S6, the fixing devices 212, 305, 312, 405, 411, 505, 513 are attached to the sealing elements 211, 304, 311, 404, 410, 504, 512, 604, such that the fixing devices 212, 305, 312, 405, 411, 505, 513 at least partially surround and compress the sealing elements 211, 304, 311, 404, 410, 504, 512, 604, thereby obtaining the sealing devices 210, 314, 315, 414, 415, 516, 517.

[0075] Preferably, the shielding unit 507 is provided in the seventh step S7. For example, the shielding unit 507 is made of aluminum, copper, or stainless steel.

[0076] Preferably, in the eighth step S8, the shielding unit 507 is mounted on the sealing device 516 such that the shielding unit 507 at least partially, and particularly completely, surrounds the sealing device 516. Using the shielding unit 507, by at least partially encapsulating the sealing element 504 and the fixing device 505, improves the usability of the sealing device 516 operating in a vacuum environment and / or EUV plasma environment within the projection exposure apparatus 100. This prevents or minimizes degassing and possible interactions with EUV-induced plasma from the sealing device 516.

[0077] In an alternative embodiment of the method according to the invention, after step S4, the shielding unit 515 is provided in step S4.1 and attached to the sealing element 512 in step S4.2. In subsequent steps S5 and S6, a fixing device 513 is provided and attached to the shielding unit 515 and the underlying sealing element 512. In particular, if the shielding unit 515 is designed as a foil, a more stable attachment can be achieved by this embodiment of the method, because the fixing device 513 also has the attachment effect for the shielding unit 515 in this case.

[0078] Figure 8An embodiment of a clamp 800 as a fixing element having an open thread 806 for a variation of a component according to the invention is shown. The clamp 800 is made of, for example, stainless steel and includes a generally circular body 801, which also includes a positioning aid 802 for improving the fixing of a sealing element (not shown). Furthermore, the clamp 800 includes two connecting regions 803, 804 mounted on the upper region of the body 801. In this case, a gap 805 is formed between the two connecting regions 803, 804. Through the gap 805, the thread 806 arranged in the first connecting region 803 is open in the disassembled state and therefore freely accessible, for example, for cleaning. To fix the clamp 800 to the sealing element, a screw 807 is guided through a slot 808 in the second connecting region until the screw 807 engages with the thread 806 by rotational movement. Therefore, the gap 805 decreases with continued rotational movement, and the clamp 800 can thereby fix the sealing element to the connecting regions (both not shown).

[0079] List of reference numerals

[0080] 100 projection exposure equipment

[0081] 101 Lighting System

[0082] 102 radiation source

[0083] 103 Illumination Optical Unit

[0084] 104 Sites

[0085] 105 object plane

[0086] 106 mask master

[0087] 107 Mask Master Retainer

[0088] 108 projection optical units

[0089] 109 Image Field

[0090] 110 image plane

[0091] 111 chip

[0092] 112 chip holder

[0093] 113EUV radiation

[0094] 114 intermediate focal plane

[0095] 115-field faceted mirror

[0096] 116-Pupil Plane-Reflecting Mirror

[0097] Other reflectors of the 117-119 illumination optics unit

[0098] Other optical elements of the 120-125 projection optical unit

[0099] 126 light collector mirror

[0100] 200 optical components

[0101] 201 Mirror Substrate

[0102] 202 reflective surface

[0103] Channel 203

[0104] 204 input

[0105] 205 output component

[0106] 206 Metal Pipe Section

[0107] 207 Metal Pipe Section

[0108] 208 connection area

[0109] 209 Connection Area

[0110] 210 Sealing Device

[0111] 211 Sealing element

[0112] 212 Fixture

[0113] 300 optical components media delivery tube system

[0114] 301 is a pipe section made of silicon-containing substrate material.

[0115] 302 metal pipe section

[0116] 303 Connection Area

[0117] 304 sealing element

[0118] 305 Fixture

[0119] 306 mirror axis

[0120] 307 Optical Components Media Delivery Tube System

[0121] 308 is a pipe section made of silicon-containing substrate material.

[0122] 309 Metal Pipe Section

[0123] 310 connection area

[0124] 311 sealing element

[0125] 312 Fixing device

[0126] 313 Mirror Axis

[0127] 314 Sealing Device

[0128] 315 Sealing Device

[0129] 400 optical components media delivery tube system

[0130] 401 is a pipe section made of silicon-containing substrate material.

[0131] 402 Metal Pipe Section

[0132] 403 Connection Area

[0133] 404 sealing element

[0134] 405 Fixture

[0135] 406 optical component media delivery tube system

[0136] 407 is a pipe section made of silicon-containing substrate material.

[0137] 408 metal pipe section

[0138] 409 Connection Area

[0139] 410 sealing element

[0140] 411 Fixing device

[0141] 412 web

[0142] 413 web

[0143] 414 Sealing Device

[0144] 415 Sealing Device

[0145] 500 optical components media delivery tube system

[0146] 501 is a tube section made of silicon-containing substrate material.

[0147] 502 metal pipe section

[0148] 503 Connection Area

[0149] 504 sealing element

[0150] 505 Fixture

[0151] 506 mirrored axis

[0152] 507 Shielding Unit

[0153] 508 Optical Components Media Delivery Tube System

[0154] 509 is a pipe section made of silicon-containing substrate material.

[0155] 510 metal pipe section

[0156] 511 connection area

[0157] 512 sealing element

[0158] 513 Fixture

[0159] 514 mirror axis

[0160] 515 shielding unit

[0161] 516 Sealing Device

[0162] 517 Sealing Device

[0163] Media delivery tube system for 600 optical components

[0164] 601 is a pipe section made of silicon-containing substrate material.

[0165] 602 Metal Pipe Section

[0166] 603 Connection Area

[0167] 604 sealing element

[0168] 605 Installation Cone

[0169] S1 First Method Step

[0170] S2 Second Method Steps

[0171] S3 Third Method Steps

[0172] S4 Fourth Method Steps

[0173] S5 Fifth Method Step

[0174] S6 Sixth Method Step

[0175] S7 Seventh Method Steps

[0176] S8 Eighth Method Step

[0177] S4.1 Alternative Method Steps

[0178] S4.2 Alternative Method Steps

[0179] 800 clamps

[0180] 801 main body

[0181] 802 Positioning Auxiliary Components

[0182] 803 First Connection Area

[0183] 804 Second Connection Area

[0184] 805 gap

[0185] 806 thread

[0186] 807 screws

[0187] 808 slot hole

Claims

1. An optical component (200) for EUV lithography, comprising a dielectric delivery tube system (300, 307, 400, 406, 500, 508) for operation in a vacuum environment, wherein the dielectric delivery tube system (300, 307, 400, 406, 500, 508) includes at least one connection region (209, 303, 310, 403, 409, 502, 511) between a metal segment (207, 302, 309, 402, 408, 502, 510) and a segment (205, 301, 308, 401, 407, 501, 509) made of a silicon-containing substrate material with a linear expansion coefficient of less than 3 ppm / K, characterized in that, The connection areas (209, 303, 310, 403, 409, 503, 511) are at least partially surrounded by externally adjacent sealing devices (210, 314, 315, 414, 415, 516, 517), wherein the sealing devices (210, 314, 315, 414, 415, 516, 517) include sealing elements (211, 304, 311, 404, 410, 504, 512) and The fixing devices (212, 305, 3012, 405, 411, 505, 513) attach the sealing elements (211, 304, 311, 404, 410, 504, 512) to the connection areas (209, 303, 310, 403, 409, 503, 511), and wherein the sealing elements (211, 304, 311, 404, 410, 504, 512) include an elastomer.

2. The optical component according to claim 1, characterized in that, The sealing device (516, 517) also includes a shielding unit (507, 515).

3. The optical component according to claim 1 or 2, characterized in that, The sealing devices (210, 314, 315, 516, 517) have mirror axes (306, 313, 506, 514) parallel to the connecting regions (209, 303, 310, 503, 511).

4. The optical component according to any one of the preceding claims, characterized in that, The media delivery pipe system (300, 307, 400, 406, 500, 508) is a water delivery pipe system used for temperature control of the optical component.

5. The optical component according to claims 1 to 3, characterized in that, The media delivery pipe system (300, 307, 400, 406, 500, 508) is a gas delivery pipe system.

6. The optical component according to any one of the preceding claims, characterized in that, The connection areas (209, 303, 310, 403, 409, 503, 511) have welding, brazing, bonding or clamping interfaces.

7. The optical component according to any one of the preceding claims, characterized in that, The metal sections (207, 302, 309, 402, 408, 502, 510) include stainless steel, aluminum, nickel, or copper.

8. The optical component according to any one of the preceding claims, characterized in that, The sections (205, 301, 308, 401, 407, 501, 509) made of silicon-containing substrate material include quartz glass, titanium-doped quartz glass, or SiSiC.

9. The optical component according to any one of the preceding claims, characterized in that, The sealing elements (211, 304, 311, 404, 410, 504, 512) comprise fluoropolymers.

10. The optical component according to any one of the preceding claims, characterized in that, The fixing devices (212, 305, 312, 405, 411, 505, 513) include stainless steel clamps (800).

11. The optical component according to claim 10, characterized in that, The clamp (800) has an open thread (806) for threaded connection.

12. A projection exposure apparatus (100), particularly for EUV lithography, comprising an optical component (200) as described in any of the preceding claims.

13. A method for mounting a sealing device (210, 314, 315, 414, 415, 516, 517) for use in mounting a sealing device for use in connection regions (209, 303, 310, 310, 303, 310, 303, 310, 307, 400, 406, 500, 508, 600) between metal sections (207, 302, 309, 402, 408, 502, 510, 603) of a media delivery tube system (300, 307, 400, 406, 500, 508, 600) of an optical component (200) for use in a vacuum environment and sections (205, 301, 308, 401, 407, 501, 509, 601) made of a silicon-containing substrate material with a linear expansion coefficient of less than 3 ppm / K. -A mounting cone (605) (S1) is provided at the open end of the first section (601). -Provide sealing elements (211, 304, 311, 404, 410, 504, 512, 604) (S2). - Place the sealing element (211, 304, 311, 404, 410, 504, 512, 604) on the mounting cone (605) at the opening end of the first section (601) (S3). - The sealing elements (211, 304, 311, 404, 410, 504, 512, 604) are stretched and fitted onto the first section (601), wherein the sealing elements (211, 304, 311, 404, 410, 504, 512, 604) are moved to the connecting region (603) and surround the connecting region (603) (S4). - Provide fixing devices (212, 305, 3012, 405, 411, 505, 513) (S5). - Attach the fixing devices (212, 305, 3012, 405, 411, 505, 513) to the sealing elements (211, 304, 311, 404, 410, 504, 512, 604) such that the fixing devices (212, 305, 3012, 405, 411, 505, 513) at least partially surround and compress the sealing elements (211, 304, 311, 404, 410, 504, 512, 604), thereby obtaining the sealing devices (210, 314, 315, 414, 415, 516, 517) (S6).

14. The method of claim 13, further comprising: - Provide shielding unit (507) (S7). - Attach the shielding unit (507) to the sealing device (516) such that the shielding unit (507) at least partially, and in particular completely, surrounds the sealing device (516) (S8).

15. The method according to claim 13, characterized in that, After the sealing element (512) is stretched and fitted, a shielding unit (515) is provided (S4.1), and the shielding unit is attached to the sealing element (512) such that the shielding unit at least partially, and in particular completely, surrounds the sealing element (512) (S4.2).

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