Closure device for a lithography system and / or a mask testing device and lithography system / mask testing device

Abstract

Closure device (100) for a lithography system (1) and / or mask testing device (1), comprising a shutter disc (106) rotatably mounted about an axis of rotation (A) with at least one opening (108) spaced apart from the axis of rotation (A) for allowing working light (16) of the lithography system (1) or mask test device (1) to pass through, and a magnetic drive and bearing device (110) by means of which the shutter disc (106) is rotatably mounted about the axis of rotation (A) and which is configured to drive the shutter disc (106) in a rotating manner about the axis of rotation (A), wherein the shutter disc (106) and the drive and bearing device (110) are configured to be arranged within a vacuum housing (200) of the lithography system (1) or mask testing device (1).

Description

[0001] The present invention relates to a closure device for a lithography system and / or a mask testing device and a lithography system / mask testing device with such a closure device.

[0002] Microlithography is used to manufacture microstructured components, such as integrated circuits. The microlithography process is carried out using a lithography system, which includes an illumination system and a projection system. The image of a mask (reticule) illuminated by the illumination system is projected by the projection system onto a substrate, such as a silicon wafer, coated with a photosensitive layer (photoresist) and positioned in the image plane of the projection system. This transfers the mask structure onto the photosensitive coating of the substrate.

[0003] Driven by the pursuit of ever smaller structures in the fabrication of integrated circuits, EUV lithography systems are currently being developed that use light with a wavelength in the range of 0.1 nm to 30 nm, particularly 13.5 nm. Since most materials absorb light of this wavelength, such EUV lithography systems must use reflective optics, i.e., mirrors, instead of the refracting optics, i.e., lenses, used previously.

[0004] The performance of the lithographic systems used is determined not only by the imaging properties of the projection system but also by an illumination system that lights up the mask. This illumination system typically includes light sources, which may be pulsed lasers or plasma sources, and other optical elements that generate light beams from the light emitted by the light source. These beams converge at points on the mask. It is desirable to adjust and test the generation of these light beams and the resulting beam path in each lithographic system before delivery.

[0005] To test a lithography system, or even to test photomasks intended for use with the system, it is desirable to test the entire system or parts thereof before actual commissioning and before exposing wafers with the original light source for EUV lithography. Since EUV light sources, in particular, cannot be switched on and off efficiently, controlled blocking of the light in the beam path using a shutter within the lithography system is necessary.

[0006] Common optical or photographic shutters include, for example, linear slits that move at high speed across a window through which light can pass. Such slit shutters can be constructed using several movable blades. Rotating crescent-shaped discs driven by an electric motor are also known. Disadvantages of these include the large number of mechanical components and the vibrations that can arise, for example, from the eccentric mounting of the moving components.

[0007] Furthermore, DE 10 2011 087 851 A1 discloses a closure device for a lithography apparatus, comprising a housing for maintaining an ultra-high vacuum and a disk provided within the housing that is rotatable about an axis of rotation. The disk has at least one opening arranged on a circumferential line around the axis of rotation for the passage of ultraviolet light.

[0008] Furthermore, US patent 2005 / 0151952 A1 discloses a variable shutter lithography system comprising a light source, a shutter assembly, and a lens assembly. The shutter assembly has a variable opening range. It can contain multiple triple-blade shutters and uses stepper motors to adjust the relative positions of the triple-blade shutters. The opening range is adjusted depending on the intensity of the light source or the required dose.

[0009] Furthermore, US 2017 / 0255106 A1 discloses a shutter unit that opens and closes an optical light path for a lithography device. The shutter unit comprises a motor that rotatably drives a shaft extending along a rotational axis of the motor, and a plurality of shutter parts attached to the shaft, each comprising a light-blocking section and a light-transmitting section.

[0010] Against this background, one object of the present invention is to provide an improved closure device for a lithography system and / or mask testing device.

[0011] According to a first aspect, a closure device for a lithography system and / or mask testing device is proposed. The closure device comprises a closure disc rotatably mounted about an axis of rotation, with at least one opening spaced from the axis of rotation for allowing working light from the lithography system and / or the mask testing device to pass through. Furthermore, the closure device includes a magnetic drive and bearing assembly by means of which the closure disc is rotatably mounted about the axis of rotation and which is configured to drive the closure disc in rotation about the axis of rotation. The closure disc and the drive and bearing assembly are also configured to be arranged within a vacuum housing of the lithography system or the mask testing device.

[0012] The shutter device allows the working light of the lithography system or the mask testing device to be switched on and off. This enables testing of the lithography system and / or a photomask that is to be imaged by the lithography system. This test can be performed before actual commissioning and before exposing a substrate (e.g., a wafer) with the working light. By using the shutter device, the working light, which is also used during operation of the lithography system to image a photomask onto a substrate, can also be used during testing. In particular, during testing, the working light in the beam path within the lithography system or the mask testing device can be controlled and blocked using the shutter device, without having to switch a light source (e.g., an EUV light source) on and off, which would otherwise be very difficult.

[0013] The magnetic mounting of the locking disc eliminates mechanical friction, such as that which occurs with mechanical mountings (e.g., plain bearings, ball bearings, etc.). This prevents the generation of particles and eliminates the need for lubricant. Consequently, the service life of the locking device is significantly extended.

[0014] Furthermore, in the proposed locking device, the magnetic drive and bearing assembly provides both the magnetic drive and the magnetic bearing of the locking disc. In other words, the magnetic drive and bearing assembly is a device in which the same components (e.g., the same magnets and magnetic coils) provide both the magnetic drive and the magnetic bearing.

[0015] The proposed locking device thus has a significantly simplified configuration compared to the prior art. It can therefore be manufactured more easily and cost-effectively. Furthermore, the installation space required for the locking device is considerably reduced compared to the prior art.

[0016] A simpler configuration is also created by arranging the entire magnetic drive and bearing assembly inside the vacuum housing.

[0017] The lithography system (projection exposure system) can be an EUV lithography system. EUV stands for "Extreme Ultraviolet" and refers to a wavelength of the working light between 0.1 nm and 30 nm, specifically 13.5 nm. The lithography system can also be a DUV lithography system. DUV stands for "Deep Ultraviolet" and refers to a wavelength of the working light between 30 nm and 250 nm.

[0018] The lithography system comprises an illumination system and a projection system. In a microlithographic process, the lithography system projects the image of a mask (reticule) illuminated by the illumination system onto a substrate, such as a silicon wafer, coated with a photosensitive layer (photoresist) and positioned in the image plane of the projection system. This transfers the mask structure onto the photosensitive coating of the substrate. The optics used can have a reducing magnification ratio, for example, a magnification ratio of 1:4.

[0019] To test the lithography system (e.g., the projection optics) and / or a mask to be imaged, the lithography system can be modified and, for example, include a camera (in the image plane of the projection system) for capturing the imaged mask. The camera may have a CCD and / or CMOS image sensor. The modified lithography system with the camera thus allows for testing components of the lithography system and / or a mask under the original working light, for example, EUV light of 13.5 nm. The shutter mechanism allows for precise setting of the camera's exposure time.

[0020] If the lithography system is used for testing masks for lithography, the modified lithography system can also be referred to as a mask testing device. The camera unit of the modified lithography system, or mask testing device, allows masks to be tested within the lithography system without the need for scanning them using a microscope. Furthermore, if the modified lithography system is indeed a mask testing device, it can be equipped with a test optic that provides a magnifying image instead of an optic that uses a reducing magnification to project the mask. In other words, in this embodiment of the modified lithography system or mask testing device, the projection optic has a magnifying optic instead of a reducing optic.The magnifying optics provide a magnification of approximately 1:250 or 1:500, but only as an example. The mask testing device allows masks to be measured and examined under original exposure light using the integrated camera.

[0021] The modified lithography system or mask testing device includes a vacuum housing and a vacuum pump for evacuating the vacuum housing. The vacuum housing and vacuum pump are specifically designed to create and maintain a vacuum inside the vacuum housing. The vacuum provided has, for example, a pressure of 10 -7 up to 10 -12 mbar (hPa). For example, both the projection optics and the illumination optics are arranged inside the vacuum housing.

[0022] The sealing disc and the drive and bearing assembly are specifically designed to be arranged completely within the vacuum housing.

[0023] A vacuum housing is particularly important in EUV lithography. Since EUV radiation is strongly absorbed in many materials, it is necessary to operate the beam path – i.e., the optics, masks, reticles, target surfaces such as wafers, and the like – in a suitable lithography system under a vacuum (e.g., ultra-high vacuum).

[0024] The closing disc of the closing device is, for example, inserted into a beam path of the modified lithography system or the mask testing device within the illumination optics.

[0025] The proposed locking device can also be referred to as a rotary locking device (rotational shutter device) or a rotating locking disc (shutter disc).

[0026] The locking disc, for example, is rotationally symmetrical with respect to the axis of rotation.

[0027] A rotary locking device, particularly one with a rotationally symmetrical locking disc, offers the advantage over slotted locking devices or rotating discs with non-rotationally symmetrical geometry that a particularly high rotational speed (i.e., high angular frequency) can be achieved. Preferably, the locking disc is driven to rotate at a constant speed. Both the rotational symmetry and the constant rotational speed help to minimize vibrations of the locking device.

[0028] The shutter disc has at least one opening for transmitting the working light. This opening is spaced apart from the axis of rotation. In particular, the opening is arranged on a circumferential line around the axis of rotation. When the disc rotates around the axis of rotation and a beam of working light incident substantially parallel to the axis of rotation is emitted, the opening in the shutter disc releases the beam.

[0029] The shutter disc has at least one covering area located outside the at least one opening for covering the work light. When the disc rotates around its axis of rotation and a beam of the work light incident substantially parallel to the axis of rotation is present, the at least one covering area of ​​the shutter disc covers the beam (e.g., completely).

[0030] The at least one opening is specifically designed to allow the passage of EUV light (or DUV light).

[0031] The closure disc preferably comprises several openings, the multiple openings being arranged on the circumferential line around the axis of rotation. The multiple openings are, for example, evenly distributed, i.e., arranged at regular intervals from one another, on the common circumferential line. This regular, e.g., rotationally symmetrical, arrangement of the openings helps to minimize vibrations caused by rotation around the axis of rotation. For example, three openings can be provided on the circumferential line at angular intervals of 120° from one another. However, a different number of openings is also possible. Preferably, the openings are arranged symmetrically with respect to the axis of rotation. Preferably, the center of gravity of the closure disc lies on the axis of rotation.

[0032] The sealing disc can be formed from a circular disc.

[0033] A light source in the lithography system or mask testing device generates, for example, pulsed radiation (e.g., pulsed EUV radiation). This means that the working light incident on the shutter disc is, for example, pulsed radiation. If the light source generates pulsed radiation with a predetermined pulse duration and frequency, then by appropriately synchronizing the shutter disc's exposure time with the pulse duration and frequency of the radiation, either the radiation can be blocked or the radiation pulses can be controlled and passed on.

[0034] The locking disc is mounted exclusively magnetically. This means the locking disc is mounted without contact. Specifically, the locking disc is mounted in such a way that it is suspended freely within a magnetic field generated by the magnetic drive and bearing unit.

[0035] For the magnetic mounting of the locking disc, the magnetic drive and bearing unit requires energization. A settling bearing and / or emergency bearing may be provided, on which the locking disc can rest and / or run in the event of a power failure of the drive and bearing unit. The settling bearing / emergency bearing may, for example, be a plain bearing and / or a rolling bearing, such as a ball bearing. The rolling bearing, for example, has rolling elements (e.g., balls in the case of a ball bearing) and a raceway on which the rolling elements run. The rolling elements may be made of, for example, plastic, polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK), a polyamide, and / or ceramic. The raceway may also be made of, for example, plastic, polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK), a polyamide, and / or ceramic. However, the raceway may also be made of, for example, stainless steel.Roller elements made of plastic, polytetrafluoroethylene, polyetheretherketone, polyimide, and / or ceramic (and also running surfaces made of these materials) offer the advantage of lower outgassing and are therefore particularly suitable for use in a vacuum. Roller elements made of plastic, polytetrafluoroethylene, polyetheretherketone, polyimide, and / or ceramic also have the advantage that no lubricant is required, which is also beneficial in a vacuum environment. Alternatively, the roller elements and the running surface can both be made of stainless steel, and a vacuum-compatible lubricant can be used. A vacuum-compatible lubricant is, for example, a lubricant containing polytetrafluoroethylene (PTFE) in a binder, such as perfluoropolyether (PFPE).

[0036] For example, the diameter of the sealing disc is 500 mm or less, 400 mm or less, 300 mm or less, 200 mm or less, 150 mm or less and / or 100 mm or less.

[0037] For example, the height and / or maximum height of the closure disc is 100 mm or less, 80 mm or less, 50 mm or less, 30 mm or less and / or 10 mm or less.

[0038] For example, the material of the locking disc includes aluminum, an aluminum alloy, stainless steel and / or titanium.

[0039] For use in a vacuum, the surface of the sealing disc, for example, is designed to be very smooth. This is because contaminants are less likely to adhere to and / or adsorb onto a very smooth surface. A surface roughness R a The sealing disc, for example, has a value of 1.0 or less, 0.8 or less, 0.5 or less and / or 0.1 or less.

[0040] The magnetic drive and bearing device is designed, for example, to drive the closure disc at a rotational frequency of 15,000 revolutions per minute or more, 50,000 revolutions per minute or more and / or 100,000 revolutions per minute or more.

[0041] Furthermore, the magnetic drive and bearing device is designed to magnetically mount and drive the closure disc by means of a magnetic force acting essentially radially on the closure disc.

[0042] This allows for the simple implementation of rotation and precise positioning of the closure disc using the magnetic drive and bearing system. In particular, the arrangement and design of the magnetic drive and bearing system, such that the closure disc is driven and supported by a magnetic force acting primarily radially on it, enables highly accurate adjustment of the x-position and y-position of the closure disc. Here, the x-position is a position relative to a first direction perpendicular to the axis of rotation (x-direction), and the y-position is a position relative to a second direction perpendicular to both the first and the axis of rotation (y-direction). This highly accurate positioning and support of the closure disc with respect to its x- and y-positions significantly minimizes vibrations.In particular, the x and y positions of the locking disc can also be positioned precisely without the need for mechanical balancing.

[0043] This is a significant advantage over a magnetic drive and / or bearing system where a magnetic force acts essentially parallel to the axis of rotation (e.g., through magnetic coils arranged above magnets with respect to a rotational axis). In such a case, readjustment in the x and / or y direction would always result in a change in the rotational position relative to the axis of rotation, a change in the rotational position relative to the y-direction, and a change in the position relative to the direction defined by the axis of rotation (z-direction). This so-called crossover behavior would generate corresponding undesirable vibrations. By orienting the applied magnetic force essentially radially onto the locking disc, as proposed here, these vibrations can be prevented.

[0044] A magnetic force acting essentially radially on the locking disc is a magnetic force acting essentially perpendicular to the axis of rotation. The radial direction is a radial direction defined with respect to rotation about the axis of rotation.

[0045] A magnetic force acting substantially radially on the closure disc includes a magnetic force acting exactly radially on the closure disc, as well as a magnetic force that deviates from the exactly radial direction by ± 3° or less, by ± 1° or less, by ± 0.5° or less, by ± 0.1° or less and / or by ± 0.05° or less.

[0046] In embodiments, the closure disc has a main extension plane which is arranged essentially perpendicular to the axis of rotation, and the magnetic drive and bearing device is configured to magnetically mount and drive the closure disc by means of a magnetic force acting essentially parallel to the main extension plane.

[0047] That the principal extension plane of the shutter disc is arranged substantially perpendicular to the axis of rotation includes an arrangement of the principal extension plane exactly perpendicular to the axis of rotation as well as an arrangement of the principal extension plane that deviates from the exactly perpendicular direction by ± 3° or less, by ± 1° or less, by ± 0.5° or less, by ± 0.1° or less and / or by ± 0.05° or less.

[0048] The magnetic force acting essentially parallel to the main extension plane of the shutter disc includes a direction of action exactly parallel to the main extension plane as well as a direction of action that deviates from the direction arranged exactly parallel to the main extension plane by ± 3° or less, by ± 1° or less, by ± 0.5° or less, by ± 0.1° or less and / or by ± 0.05° or less.

[0049] According to a further embodiment, the magnetic drive and bearing device comprises several magnets provided on an inner edge of the closure disc and several magnetic coils spaced apart from the closure disc and the magnets. Furthermore, the magnets and the magnetic coils are configured to cooperate to provide magnetic bearing and magnetic drive for the closure disc.

[0050] The magnets and magnetic coils together form, in particular, both an electric motor and a magnetic bearing. The magnets and magnetic coils act together, for example, as a type of linear motor.

[0051] The magnets provided on the closure disc are, for example, magnets attached to the closure disc (e.g. glued on).

[0052] The magnets each contain, for example, neodymium magnets.

[0053] The magnets can, for example, be completely coated (i.e., nickel-plated) with nickel.

[0054] The magnetic coils each contain, for example, a wound wire (e.g., copper wire). The wire is wound around a core.

[0055] For example, one surface of the magnets (e.g., the nickel-plated magnets) has a surface roughness R. aof 1.0 or less, 0.8 or less, 0.5 or less, and / or 0.1 or less. A very smooth surface is advantageous for use in a vacuum, as contaminants are less likely to adhere to it.

[0056] In the event that the magnetic coils do not have a plastic sheath (i.e., no plastic sheath in addition to wire insulation), the surface of the coil cores and / or the stator may also have, for example, a surface roughness R. a exhibit values ​​of 1.0 or less, 0.8 or less, 0.5 or less and / or 0.1 or less.

[0057] A central axis of the magnetic coils is preferably aligned radially (with respect to the rotation of the disk).

[0058] The magnets and the magnetic coils are both specifically designed to be arranged inside the vacuum housing.

[0059] Because the magnets are positioned on the inner edge of the locking disc (instead of on or near an outer edge), they cover a smaller area (relative to a principal plane of the disc perpendicular to the axis of rotation). Consequently, the area occupied by the magnetic coils is also smaller. This allows for a more compact design of the magnetic drive and bearing assembly, thus saving installation space. Furthermore, the magnetic drive and bearing assembly can be manufactured more simply and cost-effectively. Additionally, outgassing (outgassing rate) from the magnetic coils is reduced.

[0060] The inner edge of the locking disc, for example, has a circular shape. The inner edge of the locking disc is, for example, rotationally symmetrical about the axis of rotation.

[0061] The magnetic coils are arranged at a distance from the magnets. A gap is located between the magnetic coils and the magnets. Alternatively, a gap can be said to be located between the shutter disc with the magnets and the stator with the magnetic coils. This gap has, by way of example, a width of 0.5 mm or less, 0.3 mm or less, and / or 0.2 mm or less.

[0062] According to a further embodiment, the closing disc forms a rotor of the drive and bearing device, the closing disc has a central recess which has the axis of rotation, and the magnetic drive and bearing device has a stator spaced apart from the closing disc and arranged within the central recess.

[0063] The central recess, for example, is a recess that is rotationally symmetrical with respect to the axis of rotation.

[0064] The central recess is defined by an inner edge of the closure disc, i.e., surrounded and / or limited.

[0065] The central recess of the shutter disc is in particular spaced apart and separated from the at least one opening of the shutter disc for letting through working light.

[0066] The magnetic drive and bearing device has, for example, several magnets provided (e.g., attached) to the inner edge of the closure disc and several magnetic coils arranged on the stator.

[0067] The stator with the magnetic coils is spaced apart from the closing disc with the magnets. A magnetic field from the magnetic drive and bearing mechanism acts in the space formed between them.

[0068] According to another embodiment, the stator has a diameter of 100 mm or less, 80 mm or less, 50 mm or less, 30 mm or less and / or 10 mm or less, and / or the stator has a height of 100 mm or less, 80 mm or less, 50 mm or less, 30 mm or less and / or 10 mm or less.

[0069] The height of the stator can be, for example, one third or less and / or one quarter or less of the diameter of the stator.

[0070] The smaller the beam diameter (i.e., beam cross-section) at the point where the shutter disc is used, the smaller the diameter of the shutter disc can be. For illustrative purposes, the shutter disc is positioned in a beam path between two mirrors of the illumination system. The beam diameter of a beam between the two mirrors narrows, for example, from the first of the two mirrors to an intermediate focus. Furthermore, the beam widens again, for example, from the intermediate focus to the second of the two mirrors. The shutter disc is designed, for example, to be positioned near the intermediate focus. Since the beam cross-section is particularly small there, the diameter of the shutter disc can also be particularly small (e.g., 50 mm or less, 30 mm or less, and / or 10 mm or less).

[0071] In embodiments where the magnetic coils are encased in a plastic material (in addition to wire insulation) (plastic sheathing), the stator with the plastic sheathing can have a diameter of 100 mm or less, 80 mm or less, 50 mm or less, 30 mm or less, and / or 10 mm or less. Furthermore, in this case, the stator with the plastic sheathing can have a height of 100 mm or less, 80 mm or less, 50 mm or less, 30 mm or less, and / or 10 mm or less.

[0072] According to another embodiment: The magnetic drive and bearing device has several sensor units for detecting the position of the closing disc, and / or The magnetic drive and bearing device has several sensor units for detecting a rotational position of the closure disc with respect to a rotation about the axis of rotation, an x-position with respect to a first direction arranged perpendicular to the axis of rotation and / or a y-position with respect to a second direction arranged perpendicular to the first and to the axis of rotation.

[0073] The sensor units allow for precise detection of the position of the locking disc. For example, the sensor units can detect the position of the locking disc once or several times per revolution.

[0074] The multiple sensor units are arranged, in particular, on a stator of the magnetic drive and bearing device. The multiple sensor units are arranged, for example, around the perimeter of the stator, e.g., on an outer radius or outer edge of the stator.

[0075] The rotational position of the locking disc with respect to a rotation about the axis of rotation has, for example, a rotational angle (i.e., angle of rotation) of a rotation about the axis of rotation. The x-position is, in particular, a position with respect to the first direction (x-direction). Furthermore, the y-position is, in particular, a position with respect to the second direction (y-direction).

[0076] The sensor units are also located within the vacuum housing.

[0077] The sensor units can be, for example, eddy current sensors, capacitive sensors and / or inductive sensors.

[0078] According to a further embodiment, the magnetic drive and bearing device comprises several magnetic coils configured to interact with magnets on the closure disc for magnetic bearing and magnetic drive of the closure disc. Furthermore, each of the multiple magnetic coils is configured as a sensor unit for detecting the position of the closure disc.

[0079] This means that the multiple magnetic coils are each configured as an actuator unit to drive the shutter disc and additionally as a sensor unit to detect the position of the shutter disc.

[0080] In this embodiment, a particularly advantageous configuration of the magnetic drive and bearing device is one in which the locking disc is magnetically mounted and driven by a magnetic force acting substantially radially on the locking disc (i.e., substantially perpendicular to the axis of rotation). This allows the magnetic coils, which also function as sensor units, to directly and accurately detect the x and y positions of the locking disc. This is not the case with a magnetic force acting substantially parallel to the axis of rotation, because in this case, the magnetic coils, designed as sensor units, can only meaningfully measure a z-position with respect to a z-direction parallel to the axis of rotation. The x and y positions could not be measured directly, but at best could only be determined by calculation using the remaining sensor values.

[0081] According to a further embodiment, the locking device has a control device for regulating, based on detected sensor data of a position of the locking disc, a magnetic drive of the locking disc and / or a magnetic bearing of the locking disc, such that an angular frequency (e.g. also rotational speed) of the locking disc is controlled with respect to a rotation about the axis of rotation, an x-position of the locking disc in a first direction perpendicular to the axis of rotation is controlled and / or a y-position of the locking disc in a second direction perpendicular to the first and to the axis of rotation is controlled.

[0082] This allows the angular frequency (e.g., rotational speed) of the shutter disc, the x-position of the shutter disc and / or the y-position of the shutter disc to be controlled in a feedback control system.

[0083] In particular, the actual angular frequency of the shutter disc can be regulated to a target angular frequency of the shutter disc, the actual x-position of the shutter disc in the first direction (x-direction) can be regulated to a target x-position, and / or the actual y-position of the shutter disc in the second direction (y-direction) can be regulated to a target y-position.

[0084] The control unit is, for example, part of a higher-level computing unit of the lithography system or the mask testing device. The control unit and / or the higher-level computing unit are, for example, located outside the vacuum housing. However, the control unit and / or the higher-level computing unit can also be located inside the vacuum housing, particularly if the respective unit is appropriately encased to prevent outgassing. Locating the control unit and / or the higher-level computing unit within the vacuum housing reduces the complexity of the device, as fewer cables, feedthroughs, and the like are required.

[0085] The control device thus allows for precise control of the angular frequency (rotational speed) of the shutter disc and its position with respect to the three degrees of freedom (i.e., rotation around the z-direction, translation in the x-direction, and translation in the y-direction). The remaining three degrees of freedom (i.e., rotation around the x-direction, rotation around the y-direction, and translation in the z-direction) are advantageously stabilized passively by automatic operation.

[0086] The computing unit can also include a trigger control unit. For example, a sensor unit can be provided to detect a rotation of the shutter disc and thus a rotational position of the at least one opening. The trigger control unit can be configured, for example, to generate a trigger signal based on the sensor data. The trigger signal can be used, for example, to activate or control a light source of the lithography system or the mask testing device. In particular, the trigger control unit can be configured to control the light source depending on the trigger signal. For example, in a first mode, the control can be such that the light source is ignited when the shutter disc, by means of its at least one opening, opens the beam path for the working light. In this case, for example, a camera device of the modified lithography system or the mask testing device can be activated.The mask test device is exposed. For example, in a second mode, the control can be such that the light source is triggered when the shutter disc blocks the beam path by means of its at least one covering area. In this case, for example, no light falls on a camera unit of the modified lithography system or the mask test device.

[0087] According to another embodiment, the control device is designed to automatically balance the closure disc by controlling the x-position and the y-position of the closure disc.

[0088] According to another embodiment, the magnetic drive and bearing device has at least one acceleration sensor, and the control device is configured to balance the closing disc based on data acquired by the at least one acceleration sensor.

[0089] The accelerometer is configured, for example, to detect vibrations (e.g., oscillations) of the magnetic drive and bearing assembly. The accelerometer is configured, for example, to detect vibrations at least in the x-direction and / or the y-direction, as the greatest vibration amplitudes are expected in these directions. The accelerometer can also be configured, for example, to detect vibrations in at least all six degrees of freedom (e.g., if the accelerometer incorporates a semiconductor element such as a MEMS sensor). The accelerometer is, for example, arranged and / or mounted on the stator. The accelerometer is, for example, arranged and / or mounted adjacent to the axis of rotation. Multiple accelerometers of the type described may also be used.

[0090] According to a further embodiment, the at least one opening of the closure disc is designed as at least one indentation on an outer edge of the closure disc.

[0091] In particular, the at least one opening is not completely surrounded (i.e., enclosed) by material of the closure disc. Rather, the at least one opening is an opening that is open in a radial direction away from the axis of rotation.

[0092] For example, the closure disc is formed from a circular disc, on the outer edge of which at least one opening is formed as at least one recess (e.g. notch).

[0093] According to a further embodiment The shutter disc has several openings along a circumferential line around the axis of rotation, and a covering area of ​​the shutter disc for covering the working light is arranged between each pair of adjacent openings along the circumferential line, and The cover area, when viewed from above parallel to the axis of rotation, has a rounded corner, and / or The working light at the location of the shutter disc has a beam cross-sectional shape and the shape of the respective covering area in a top view parallel to the axis of rotation is designed such that the respective covering area exclusively covers the beam cross-sectional shape and a tolerance area around the beam cross-sectional shape.

[0094] The rounded corners and / or the fact that the respective covering area exclusively covers the beam cross-sectional shape and the tolerance range around it allow the sealing disc to be manufactured with minimal material. This minimizes the mass and therefore the rotational energy of the sealing disc.

[0095] The fact that the respective covering area exclusively covers the beam cross-sectional shape and the tolerance range around the beam cross-sectional shape means in particular that an area outside the beam cross-sectional shape with the tolerance range is not covered by the closing disc (i.e. in any rotational position).

[0096] For example, the closure disc has several openings arranged along a circumference around the axis of rotation. For instance, the closure disc has a cover area between each pair of adjacent openings. Furthermore, the closure disc has, for example, an inner ring section (on which, for example, the magnets are located) that is connected to the multiple cover areas via corresponding bridges.

[0097] The beam cross-sectional shape is, for example, circular. However, the beam cross-sectional shape can also be elliptical, superelliptical, or otherwise shaped.

[0098] According to a further embodiment The magnetic drive and bearing device has several magnetic coils designed to interact with magnets on the closure disc for magnetic bearing and magnetic drive of the closure disc, and Do the magnetic coils each have a metal core, or The magnetic coils each have a plastic core.

[0099] The metal core can, for example, be a ferromagnetic metal core, such as iron (iron core). However, the metal core can also be a non-ferromagnetic metal core, such as one made of aluminum, copper, titanium, and / or a stainless steel alloy.

[0100] The magnetic flux can be improved by using a ferromagnetic metal core (e.g., an iron core). This metal core (e.g., an iron core) can, for example, consist of multiple metal sheets (e.g., iron sheets) to minimize remagnetization losses. A ferromagnetic and / or non-ferromagnetic metal core can also provide heat dissipation.

[0101] Using a plastic core (especially instead of a metal core) can further reduce remagnetization losses. It can also reduce heat generation. A plastic core is particularly advantageous when the locking disc is small (e.g., less than 15 cm in diameter) and therefore lightweight, requiring only minimal drive force to operate it.

[0102] The plastic core material may contain, for example, an epoxy resin and / or polyurethane (PUR).

[0103] According to a further embodiment, the magnetic drive and bearing device comprises several magnetic coils configured to interact with magnets on the closure disc for magnetic bearing and magnetic drive of the closure disc. Furthermore, each magnetic coil has a wire winding with a wire sheathed in an insulating material. The insulating material comprises polytetrafluoroethylene, polyetheretherketone, and / or a polyimide.

[0104] An insulating material containing polytetrafluoroethylene, polyetheretherketone and / or a polyimide is particularly well suited for use in a vacuum due to its low outgassing.

[0105] The wire of the magnetic coils is, for example, a copper wire.

[0106] According to a further embodiment, the magnetic drive and bearing device has several magnetic coils which are configured to interact with magnets on the closure disc for the magnetic bearing and magnetic drive of the closure disc. Furthermore, the magnetic coils are encased in a plastic material.

[0107] The coating with the plastic material can be provided in addition to the aforementioned wire insulation.

[0108] The plastic material reduces and / or prevents outgassing. This prevents contamination and / or disruption of the vacuum in the vacuum chamber.

[0109] The magnetic coils can be individually or jointly encased in the plastic material. For example, the stator with the magnetic coils (and, for example, coil cores) can also be encased as a whole in the plastic material.

[0110] The plastic material used to encase the magnetic coils contains, for example, an epoxy resin and / or polyurethane (PUR).

[0111] A control unit and / or a higher-level computing unit comprising the control unit can also be encased in a plastic material. In this case, the control unit or the computing unit with the control unit can also be arranged inside the vacuum housing without causing problems due to outgassing.

[0112] The plastic material (e.g., the potting compound) can optionally be coated with (non-ferromagnetic) metal to reduce outgassing. A nickel and / or chromium coating, for example, is possible. Alternatively, a suitable molded part can be placed over the plastic material. In particular, when encasing a control unit and / or a higher-level computing unit containing the control unit with a plastic material, the aforementioned molded part can be used to reduce outgassing from the plastic.

[0113] According to another embodiment, the locking device includes a cooling device for cooling the magnetic drive and bearing assembly. Furthermore, the cooling device includes: a cooling ring arranged around the sealing disc to dissipate heat, and / or a cooling housing arranged around the locking disc for heat dissipation, and / or a cooling tube with a capillary structure and a working fluid contained inside the cooling tube, wherein the cooling tube connects a space around the sealing disc with an external space.

[0114] Particles (e.g., in the event of a malfunction in the drive and bearing mechanism) can also be retained by means of the cooling ring and / or cooling housing arranged around the shutter disc. The cooling ring, for example, is a cooling housing that has only two openings, one for the incident work light and one for the emitted work light.

[0115] The cooling ring and / or the cooling housing can reduce heat radiation from the magnetic coils and / or the sealing disc.

[0116] An inner wall of the cooling ring and / or the cooling housing provides, for example, the highest possible absorption or emissivity of thermal radiation. This inner wall may, for instance, have a nickel-phosphorus coating (NiP coating) or another coating with high absorption or emissivity of thermal radiation.

[0117] For example, an outer wall of the cooling ring and / or the cooling housing provides low emissivity of thermal radiation. This outer wall might, for instance, have a polished and / or shiny metal surface.

[0118] For example, the base material of the cooling ring and / or the cooling housing has a high thermal conductivity in order to quickly conduct the heat towards the outer wall.

[0119] The cooling tube connects the space around the sealing disc to an external space. The external space is, for example, a space outside the vacuum housing. In this case, the cooling tube is designed to dissipate heat from the space around the sealing disc to the external space outside the vacuum housing.

[0120] At an end of the cooling pipe located in the outside space (i.e. at atmospheric pressure), cooling fins and / or external water cooling can optionally be provided.

[0121] This allows the locking mechanism to be cooled.

[0122] Especially with a low-mass locking disc and thus low drive energy, water cooling as conventionally used is not necessary. Instead, a cooling device comprising one or more of the proposed cooling rings, cooling housings, and / or capillary cooling tubes is sufficient.

[0123] The cooling ring and / or cooling housing contain, for example, aluminum. In particular, the cooling ring and / or cooling housing contain no iron that would interfere with the magnetic properties of the drive and bearing assembly.

[0124] The cooling housing is, for example, a closed cooling housing.

[0125] According to a second aspect, a lithography system and / or a mask testing device is proposed. The lithography system or the mask testing device comprises a closure device as described above and a vacuum housing for providing a vacuum, wherein the closure disc and the drive and bearing assembly of the closure device are arranged within the vacuum housing.

[0126] The sealing disc and the drive and bearing assembly of the sealing device are, in particular, arranged completely within the vacuum housing.

[0127] The shutter device, in particular the shutter disc and the drive and bearing assembly, is preferably used in an illumination optic of the projection exposure system. However, the shutter device, in particular the shutter disc and the drive and bearing assembly, can also be used in a projection optic. When used in a projection optic, the radiation cross-section to be covered or released is smaller. Therefore, more openings could be arranged on the shutter disc when used in a projection optic, resulting in a lower required rotational speed. Alternatively, the shutter disc can be made smaller when used in a projection optic.

[0128] The respective unit described above or below, for example, the computing device, the control device, the first and second control units, and the trigger control device, can be implemented in hardware and / or software. In a hardware implementation, the respective unit can be designed as a device or as part of a device, for example, as a computer or a microprocessor. In a software implementation, the respective unit can be designed as a computer program product, as a function, as a routine, as part of program code, or as an executable object.

[0129] The term "one" here is not necessarily to be understood as restricting the number to exactly one element. Rather, it can also refer to multiple elements, such as two, three, or more. Similarly, every other counter used here should not be interpreted as restricting the number to the exact number stated. Instead, numerical deviations, both higher and lower, are possible unless otherwise specified.

[0130] The embodiments and features described for the closure device apply accordingly to the proposed lithography system or mask testing device, and vice versa.

[0131] Other possible implementations of the invention also include combinations of features or embodiments described previously or subsequently with regard to the exemplary embodiments, even if not explicitly mentioned. In such cases, the person skilled in the art will also add individual aspects as improvements or additions to the respective basic form of the invention.

[0132] Further advantageous embodiments and aspects of the invention are the subject of the dependent claims and the exemplary embodiments of the invention described below. The invention will be explained in more detail below with reference to preferred embodiments and the accompanying figures. Fig. Figure 1 shows a schematic meridional section of a projection exposure system for EUV projection lithography according to one embodiment; Fig. Figure 2 shows a schematic cross-sectional view of a shutter device of the projection exposure system. Fig. 1 according to one embodiment; Fig. Figure 3 shows a top view of a locking disc of the locking device. Fig. 2; Fig. Figure 4 shows magnetic coils of the locking device encased in a plastic material. Fig. 2 according to one embodiment; Fig. 4A shows the magnetic coils of the locking device. Fig. 2 according to one embodiment; Fig. 4B shows a similar view Fig. 4, wherein dimensions of the magnetic coils according to one embodiment are shown; Fig. 5 shows a view similar to Fig. 3, wherein sensor units of the locking device are shown according to one embodiment; Fig. Figure 6 shows a control loop for controlling a magnetic drive and a magnetic bearing of the locking disc. Fig. 2 according to one embodiment; and Fig. Figure 7 shows several variants of a cooling device for the closure device. Fig. 2 according to one embodiment.

[0133] In the figures, identical or functionally equivalent elements have been labelled with the same reference symbols, unless otherwise indicated. Furthermore, it should be noted that the representations in the figures are not necessarily to scale.

[0134] Fig. Figure 1 shows an embodiment of a projection exposure system 1 (lithography system), in particular an EUV lithography system. One embodiment of the illumination system 2 of the projection exposure system 1 has, in addition to a light or radiation source 3, an illumination optic 4 for illuminating an object field 5 in an object plane 6. In an alternative embodiment, the light source 3 can also be provided as a separate module from the rest of the illumination system 2. In this case, the illumination system 2 does not include the light source 3.

[0135] A reticule 7 arranged in the object field 5 is exposed. The reticule 7 is held by a reticule holder 8. The reticule holder 8 can be moved, particularly in a scanning direction, via a reticule displacement drive 9.

[0136] In the Fig. Figure 1 shows a Cartesian coordinate system with an x-direction x, a y-direction y, and a z-direction z. The x-direction x runs perpendicular to the plane of the drawing. The y-direction y runs horizontally, and the z-direction z runs vertically. The scan direction runs in the Fig. 1 along the y-direction y. The z-direction z runs perpendicular to the object plane 6.

[0137] The projection exposure system 1 comprises a projection optic 10. The projection optic 10 serves to image the object field 5 onto an image field 11 in an image plane 12. The image plane 12 is parallel to the object plane 6. Alternatively, an angle other than 0° between the object plane 6 and the image plane 12 is also possible.

[0138] A structure on the reticulum 7 is imaged onto a photosensitive layer of a wafer 13 located in the image plane 12 within the image field 11. The wafer 13 is held by a wafer holder 14. The wafer holder 14 can be moved, particularly along the y-direction y, via a wafer transfer drive 15. The movement of the reticulum 7 via the reticulum transfer drive 9 and of the wafer 13 via the wafer transfer drive 15 can be synchronized.

[0139] Light source 3 is an EUV radiation source. Light source 3 emits, in particular, EUV radiation 16, which is also referred to below as useful radiation, illumination radiation, or illumination light. The useful radiation 16 has a wavelength in the range between 5 nm and 30 nm. Light source 3 can be a plasma source, for example, an LPP source (Laser Produced Plasma) or a DPP source (Gas Discharged Produced Plasma). It can also be a synchrotron-based radiation source. Light source 3 can be a free-electron laser (FEL).

[0140] The illumination radiation 16 emanating from the light source 3 is focused by a collector 17. The collector 17 can be a collector with one or more ellipsoidal and / or hyperboloid reflective surfaces. The at least one reflective surface of the collector 17 can be illuminated by the illumination radiation 16 at grazing incidence (GI), i.e., with angles of incidence greater than 45°, or at normal incidence (NI), i.e., with angles of incidence less than 45°. The collector 17 can be structured and / or coated to optimize its reflectivity for the useful radiation and to suppress stray light.

[0141] After the collector 17, the illumination radiation 16 propagates through an intermediate focus in an intermediate focal plane 18. The intermediate focal plane 18 can represent a separation between a radiation source module, comprising the light source 3 and the collector 17, and the illumination optics 4.

[0142] The illumination optics 4 comprise a deflecting mirror 19 and, downstream in the beam path, a first faceted mirror 20. The deflecting mirror 19 can be a planar deflecting mirror or, alternatively, a mirror with an effect that influences the beam shape beyond the mere deflection effect. Alternatively or additionally, the deflecting mirror 19 can be designed as a spectral filter that separates a useful wavelength of the illumination radiation 16 from stray light of a different wavelength. If the first faceted mirror 20 is arranged in a plane of the illumination optics 4 that is optically conjugate to the object plane 6 as the field plane, it is also referred to as a field faceted mirror. The first faceted mirror 20 comprises a plurality of individual first facets 21, which can also be referred to as field facets. Of these first facets 21, the following are in the Fig. 1 only some examples are shown.

[0143] The first facets 21 can be designed as macroscopic facets, in particular as rectangular facets or as facets with an arcuate or semicircular border contour. The first facets 21 can be designed as planar facets or alternatively as convexly or concavely curved facets.

[0144] As is known, for example, from DE 10 2008 009 600 A1, the first facets 21 can themselves each be composed of a plurality of individual mirrors, in particular a plurality of micromirrors. The first facet mirror 20 can in particular be designed as a microelectromechanical system (MEMS system). For details, reference is made to DE 10 2008 009 600 A1.

[0145] Between the collector 17 and the deflecting mirror 19, the illumination radiation 16 runs horizontally, i.e. along the y-direction y.

[0146] In the beam path of the illumination optics 4, a second faceted mirror 22 is arranged downstream of the first faceted mirror 20. If the second faceted mirror 22 is arranged in a pupil plane of the illumination optics 4, it is also referred to as a pupil faceted mirror. The second faceted mirror 22 can also be arranged at a distance from a pupil plane of the illumination optics 4. In this case, the combination of the first faceted mirror 20 and the second faceted mirror 22 is also referred to as a specular reflector. Specular reflectors are known from US 2006 / 0132747 A1, EP 1 614 008 B1, and US 6,573,978 B1.

[0147] The second facet mirror 22 comprises a plurality of second facets 23. In the case of a pupil facet mirror, the second facets 23 are also referred to as pupil facets.

[0148] The second facets 23 can also be macroscopic facets, which may, for example, have round, rectangular, or hexagonal edges, or alternatively, facets composed of micromirrors. Reference is also made to DE 10 2008 009 600 A1 in this regard.

[0149] The second facets 23 can have planar or alternatively convex or concave curved reflective surfaces.

[0150] The illumination optics 4 thus form a double-faceted system. This basic principle is also known as a honeycomb condenser (English: Fly's Eye Integrator).

[0151] It can be advantageous not to arrange the second faceted mirror 22 exactly in a plane that is optically conjugate to a pupil plane of the projection optics 10. In particular, the second faceted mirror 22 can be arranged tilted relative to a pupil plane of the projection optics 10, as described, for example, in DE 10 2017 220 586 A1.

[0152] With the aid of the second faceted mirror 22, the individual first facets 21 are imaged into the object field 5. The second faceted mirror 22 is the last beam-shaping, or indeed the last, mirror for the illumination radiation 16 in the beam path before the object field 5.

[0153] In another embodiment of the illumination optics 4, not shown, a transmission optic can be arranged in the beam path between the second facet mirror 22 and the object field 5, which contributes in particular to imaging the first facets 21 into the object field 5. The transmission optic can have exactly one mirror, or alternatively two or more mirrors, which are arranged one behind the other in the beam path of the illumination optics 4. The transmission optic can in particular comprise one or two mirrors for normal incidence (NI mirrors) and / or one or two mirrors for grazing incidence (GI mirrors).

[0154] The lighting optics 4, in the version shown in the Fig. Figure 1 shows exactly three mirrors after the collector 17, namely the deflecting mirror 19, the first faceted mirror 20 and the second faceted mirror 22.

[0155] In a further embodiment of the lighting optics 4, the deflecting mirror 19 can also be omitted, so that the lighting optics 4 after the collector 17 can then have exactly two mirrors, namely the first faceted mirror 20 and the second faceted mirror 22.

[0156] The mapping of the first facets 21 by means of the second facets 23 or with the second facets 23 and a transmission optic into the object plane 6 is regularly only an approximate mapping.

[0157] The projection optics 10 comprise a plurality of mirrors Mi, which are numbered according to their arrangement in the beam path of the projection exposure system 1.

[0158] In the Fig. In the example shown, the projection optics 10 comprise six mirrors M1 to M6. Alternatives with four, eight, ten, twelve, or any other number of mirrors Mi are also possible. The projection optics 10 is a doubly obscured optic. The penultimate mirror M5 and the last mirror M6 each have an aperture for the illumination radiation 16. The projection optics 10 has an image-side numerical aperture that is greater than 0.5 and can also be greater than 0.6, for example, 0.7 or 0.75.

[0159] The reflective surfaces of the mirrors Mi can be designed as freeform surfaces without an axis of rotational symmetry. Alternatively, the reflective surfaces of the mirrors Mi can be designed as aspherical surfaces with exactly one axis of rotational symmetry of the reflective surface shape. The mirrors Mi, like the mirrors of the illumination optics 4, can have highly reflective coatings for the illumination radiation 16. These coatings can be designed as multilayer coatings, in particular with alternating layers of molybdenum and silicon.

[0160] The projection optics 10 has a large object-image offset in the y-direction y between a y-coordinate of a center of the object field 5 and a y-coordinate of the center of the image field 11. This object-image offset in the y-direction y can be approximately as large as a z-distance between the object plane 6 and the image plane 12.

[0161] The projection optics 10 can be anamorphic. In particular, they have different magnifications βx, βy in the x and y directions. The two magnifications βx, βy of the projection optics 10 are preferably (βx, βy) = (+ / - 0.25, + / - 0.125). A positive magnification β indicates a projection without image inversion. A negative magnification β indicates a projection with image inversion.

[0162] The projection optics 10 thus lead to a reduction in the x-direction x, that is, in the direction perpendicular to the scan direction, in a ratio of 4:1.

[0163] The projection optics 10 lead to a reduction of 8:1 in the y-direction y, that is, in the scan direction.

[0164] Other magnification ratios are also possible. Magnification ratios with the same sign and absolute values ​​in the x and y directions (x, y), for example with absolute values ​​of 0.125 or 0.25, are also possible.

[0165] The number of intermediate image planes in the x and y directions x, y in the beam path between the object field 5 and the image field 11 can be the same or, depending on the design of the projection optics 10, different. Examples of projection optics with different numbers of such intermediate images in the x and y directions x, y are known from US 2018 / 0074303 A1.

[0166] Each of the second facets 23 is assigned to exactly one of the first facets 21 to form an illumination channel for illuminating the object field 5. This can result, in particular, in illumination according to Köhler's principle. The far field is divided into a multitude of object fields 5 with the help of the first facets 21. The first facets 21 generate a plurality of images of the intermediate focus on the second facets 23 assigned to each of them.

[0167] The first facets 21 are each superimposed on a corresponding second facet 23 to illuminate the object field 5 on the reticle 7. The illumination of the object field 5 is particularly homogeneous. It preferably exhibits a uniformity error of less than 2%. Field uniformity can be achieved by superimposing different illumination channels.

[0168] The illumination of the entrance pupil of the projection optics 10 can be geometrically defined by arranging the second facets 23. By selecting the illumination channels, in particular the subset of the second facets 23 that carry light, the intensity distribution in the entrance pupil of the projection optics 10 can be adjusted. This intensity distribution is also referred to as the illumination setting or illumination pupil filling.

[0169] Another preferred pupil uniformity in the area of ​​defined illuminated sections of an illumination pupil of the illumination optics 4 can be achieved by a redistribution of the illumination channels.

[0170] Further aspects and details of the illumination of the object field 5 and, in particular, the entrance pupil of the projection optics 10 are described below.

[0171] The projection optics 10 can, in particular, have a homocentric entrance pupil. This can be accessible. It can also be inaccessible.

[0172] The entrance pupil of the projection optics 10 cannot always be illuminated exactly by the second faceted mirror 22. When the projection optics 10 image the center of the second faceted mirror 22 telecentrically onto the wafer 13, the aperture rays often do not intersect at a single point. However, a surface can be found where the pairwise determined separation of the aperture rays is minimized. This surface represents the entrance pupil or a surface conjugate to it in real space. In particular, this surface exhibits a finite curvature.

[0173] The projection optics 10 may have different entrance pupil positions for the tangential and sagittal beam paths. In this case, an imaging element, in particular an optical component of the transmission optics, should be provided between the second faceted mirror 22 and the reticle 7. This optical element can accommodate the different positions of the tangential and sagittal entrance pupils.

[0174] During the Fig. In the arrangement of the components of the illumination optics 4 shown in Figure 1, the second faceted mirror 22 is arranged in a plane conjugate to the entrance pupil of the projection optics 10. The first faceted mirror 20 is arranged tilted relative to the object plane 6. The first faceted mirror 20 is arranged tilted relative to an arrangement plane defined by the deflecting mirror 19. The first faceted mirror 20 is arranged tilted relative to an arrangement plane defined by the second faceted mirror 22.

[0175] For example, to test the radiation source 3, the mask 13, or the imaging performance of the projection optics 10, a camera device 24 can be provided instead of a wafer 13. In other words, the element designated by the two reference numerals 13 and 24 in Fig. 1. The exposure may be either a wafer 13 (in a lithographic operation of the lithography system 1) or a camera device 24 (in a test operation of the lithography system 1). A shutter device 100 is also provided to control exposure in the test operation. The shutter device 100 has a shutter assembly 102 arranged in the beam path of the working light 16 in the illumination system 4.

[0176] Furthermore, the locking device 100 includes a computing unit 104, which can, for example, be program-controlled. The computing unit 104 is communicatively coupled to the locking device 102. The computing unit 104 receives, in particular, sensor data S. A from the locking device 102 and sends control signals S Bto the shutter device 102. Furthermore, the computing unit 104 sends control signals Sc to the radiation source 3. For example, the computing unit 104 can control the radiation source 3 to activate laser pulses for plasma discharge. The computing unit 104 also controls, for example, the shutter device 102 and the radiation source 3 such that the camera device 24 is exposed to working light 16 after passing through the projection optics 10.

[0177] During the exposure of coated semiconductor wafers, the mask structures of the mask 5 are typically imaged at a reduced size by the projection optics 10. In a modified embodiment of the lithography system 1 (e.g., as a mask testing device), the masks 5 used in wafer production can be tested and measured. When the lithography system 1 is implemented as a measuring and testing device for testing the light source 3, the mask 5, and / or the optical elements of the projection optics 10, an optical arrangement (not shown) is used that provides a magnified image (e.g., at a scale of 1:250 or 1:500) of the mask structures of the mask 5 to the camera device 24. To set a suitable exposure time for the camera device 24, the shutter device 102 is controlled accordingly.This means that in a modified lithography system 1 for testing and / or a mask testing device 1, the camera device 24 (e.g., CCD and / or CMOS) is arranged instead of the wafer 13. Furthermore, the collector 17 can also be omitted, as a sufficient amount of light may be required for operation as a test device even without the collector 17. Additionally, in a modified lithography system 1 for testing and / or a mask testing device 1, the faceted mirrors 20, 22 and their different deflections can be simulated using only two apertures in the area of ​​the reticle 7 (incoming and outgoing beam paths to the reticle 7). Different faceted mirror settings can be simulated with different apertures.

[0178] The illumination system 4, the projection system 10 and the shutter device 102 are arranged in particular within a vacuum housing 200 of the modified lithography system 1 and / or the mask testing device 1 (in Fig. 1 not shown, only in Fig. 2 shown). Inside the vacuum housing 200 there is a vacuum V (e.g. ultra-high vacuum).

[0179] Fig. Figure 2 shows a schematic cross-sectional representation of an embodiment of a locking device 100 with a locking device 102 and a calculating device 104.

[0180] As in Fig. As shown in Figure 2, the shutter device 100, in particular the shutter assembly 102, has a shutter disc 106 rotatably mounted about an axis of rotation A (angle of rotation φ). The shutter disc 106 has at least one opening 108 spaced apart from the axis of rotation A for allowing working light 16 from the modified lithography system 1 or the mask test device to pass through. Fig. Figure 3 is a top view of the locking disc 106. Fig. 2 to see ( Fig. 2 is a cross-section along line II-II in relation to the closing disc 106 and a drive and bearing device 110. Fig. 3) In the example shown of Fig. 2 and Fig. 3 The shutter disc 106 has three openings 108 arranged along a circumferential line U around the axis of rotation A for letting through working light 16. In other examples, however, a different number of openings 108 may be provided.

[0181] The locking device 100, in particular the locking assembly 102, also comprises a magnetic drive and bearing assembly 110. The locking disc 106 is rotatably mounted about the axis of rotation A by means of the magnetic drive and bearing assembly 110. That is, the locking disc 106 is mounted and positioned purely magnetically, and in particular without contact, by means of the magnetic drive and bearing assembly 110. Furthermore, the magnetic drive and bearing assembly 110 is configured to drive the locking disc 106 to rotate about the axis of rotation A at a predetermined angular frequency ω (ω = dφ / dt).

[0182] In Fig. Figure 2 shows a vacuum housing 200 of the lithography system 1 or the mask testing device, in which the closure device 102 with the closure disc 106 and the drive and bearing unit 110 is completely arranged. This allows the closure device 102 to be implemented in a particularly compact and simple manner.

[0183] The sealing disc 106 forms, in particular, a rotor of the magnetic drive and bearing unit 110. Furthermore, the magnetic drive and bearing unit 110 has a stator 112, as shown in Fig. 2 can be seen.

[0184] The magnetic drive and bearing device 110 has several magnets 116 arranged on an inner edge 114 of the locking disc 106. For the sake of clarity, only some of the magnets 116 are labeled with a reference numeral in the figures. The magnets 116 are attached to the inner edge 114 of the locking disc 106 (e.g., glued or otherwise fastened to it).

[0185] The magnets 116 can, for example, be arranged along a second circumferential line around the axis of rotation A, which is located closer to the axis of rotation A than the circumferential line U on which the at least one opening 108 is arranged.

[0186] The magnetic drive and bearing device 110 also includes several magnetic coils 118, which cooperate with the magnets 116 to provide the magnetic bearing and magnetic drive. For the sake of clarity, only some of the magnetic coils 118 are labeled with a reference numeral in the figures.

[0187] The magnetic coils 118 are arranged at a distance from the magnets 116 (i.e., without physical contact). A gap 119 with a gap width C is located between the magnetic coils 118 and the magnets 116. Alternatively, a gap 119 can be said to be arranged between the shutter disc 106 with the magnets 116 and the stator 112 with the magnetic coils 118. The gap 119 has, by way of example, a gap width C of 0.5 mm or less, 0.3 mm or less, and / or 0.2 mm or less.

[0188] The closing disk 106 has, in particular, a central recess 120 within which the stator 112 with the magnetic coils 118 is arranged. The magnetic coils 118 can, for example, be arranged along a third circumferential line around the axis of rotation A, which is located closer to the axis of rotation A than the circumferential line U on which the at least one opening 108 is arranged, and than the second circumferential line on which the magnets 116 are arranged.

[0189] As shown in the enlarged section in Fig. As can be seen in Figure 2, the magnetic drive and bearing device 110 is configured to move the locking disk 106 by means of an essentially radial (radial direction R in Fig. 2) to magnetically mount and drive the locking disk 106. In other words, a magnetic force B acts for mounting and driving essentially perpendicular to the axis of rotation A. One can also say that the locking disk 106 has a principal plane of extension E (xy-plane in Fig. 2 and Fig. 3), which is arranged essentially perpendicular to the axis of rotation A, and that the applied magnetic force B for driving and supporting the disk 106 acts essentially parallel to the main extension plane E.

[0190] This arrangement and design of the drive and bearing unit 110, and this orientation of the applied magnetic force B, allows for the simple rotation and precise positioning of the closure disc 106 using the magnetic drive and bearing unit 110. In particular, the x-position Px and y-position Py of the closure disc 106 can be set with high precision, thus reducing vibrations of the closure disc 106. Here, the x-position Px is a position relative to a first direction x (x-direction) perpendicular to the axis of rotation A, and the y-position Py is a position relative to a second direction y (y-direction) perpendicular to both the first and the axis of rotation.

[0191] The magnetic coils 118 each have, for example, a wire winding 121 with a wire 123 (e.g., copper wire). The wire 123 is, for example, sheathed with an insulating material 125. The insulating material 125 can, for example, be polytetrafluoroethylene, polyetheretherketone, and / or a polyimide.

[0192] As in Fig. As can be seen in Figure 3, the at least one opening 108 (three openings 108 in the example shown) of the closure disc 106 is formed as at least one indentation 122 on an outer edge 124 of the closure disc 106.

[0193] The closing disc 106 with the multiple (e.g., three) openings 108 has a respective covering area 126 between each pair of adjacent openings 108 along the circumferential line U. In the example of Fig. The shutter disc thus has three openings 108 and three cover areas 126. The cover areas 126 each serve to cover the work light 16 ( Fig. 2) The cover areas 126, viewed from a top view parallel to the axis of rotation A (i.e., in the view from Fig. 3) Each corner 128 is rounded. This has the advantage over non-rounded corners that material of the closure disc 106 is saved and thus the mass of the closure disc 106 is kept as low as possible.

[0194] In Fig. Figure 3 shows the cross-sectional shape 130 of the working light 16 at the location of the shutter disc 106, indicated by dashed lines. A tolerance zone 132, uniformly arranged around the cross-sectional shape 130, is also shown. In the example shown, the cross-sectional shape 130 is circular, and the tolerance zone 132 is annular around the cross-sectional shape 130. In other examples, however, the cross-sectional shape 130 and, consequently, the tolerance zone 132 may have a different shape.

[0195] For example, the closing disc 106 is designed such that its respective covering areas 126 are parallel to the axis of rotation A in the top view (i.e., in the view from Fig. 3) as seen, only the beam cross-sectional shape 130 together with the tolerance range 132 is covered. In particular, an area outside the beam cross-sectional shape 130 together with the tolerance range 132 of the working light 16 is not covered by the covering area of ​​the shutter disc 106. This also serves to save material of the shutter disc 106 and to keep the mass of the shutter disc 106 as low as possible. Because a low mass of the shutter disc 106 means that little rotational energy is required to drive the shutter disc 106 in rotation. Since only a small amount of rotational energy has to be provided by the drive and bearing unit 110, the drive and bearing unit 110 can be designed to be even more compact and simpler.Another advantage of a lower mass of the locking disc 106 is that in the event of a failure of the drive and bearing unit 110, a settling bearing (not shown) - also called emergency bearing or catch bearing - is subjected to less stress.

[0196] As in Fig. As shown in Figure 3, the magnetic coils 118 arranged on the stator 112 can each have an iron core 134, which can improve the magnetic flux. Alternatively – i.e., instead of an iron core 134 – the magnetic coils 118 can each have a non-ferromagnetic core (not shown) or a plastic core 136. A plastic core 136 can reduce remagnetization losses. For clarity, only some of the cores 134, 136 are labeled with a corresponding reference symbol.

[0197] As in Fig. As illustrated in Figure 4, the magnetic coils 118 of the stator 112' can be encased in a plastic material 138. This reduces or prevents outgassing into the vacuum V. The plastic encasement 138 can, in particular, be added to the wire insulation 125 ( Fig. 2) be ordered.

[0198] The plastic coating 138 can also be designed to be significantly thinner than in Fig. 4 shown. For example, the plastic coating 138 is designed to be so thin that a gap (similar to the gap 119 in Fig. 2) between the magnets 116 and the magnetic coils 118 with the plastic sheathing 138 a gap width (similar to the gap width C in Fig. 2) has a thickness of 0.5 mm or less, 0.3 mm or less and / or 0.2 mm or less.

[0199] The encapsulation with the plastic material 138 is produced, for example, in a first step by moving (e.g., immersing) the stator 112' with the attached magnetic coils 118 into a liquid and / or viscous plastic material (e.g., epoxy resin, PUR, etc.). The liquid and / or viscous plastic material is provided, for example, in a molding container. The container may contain, for example, an insulating material, plastic, aluminum, and / or titanium. The container may, for example, not contain iron. In a second step, the liquid and / or viscous plastic material is cured. A cover plate can optionally be placed on the cured plastic material. In a third step, the molding container is removed. The described steps are carried out, for example, under a vacuum atmosphere.

[0200] In Fig. 4A and Fig. 4B are dimensions of the stator 112, 112' with the magnetic coils 118 - once without the plastic casing 138 ( Fig. 4A) and once with the plastic casing 138 ( Fig. 4B) - illustrated. As shown in Fig. 4A, the stator 112 has a diameter D1 and a height H1. The height H1 refers, for example, to a direction z that is perpendicular to the diameter D1. For example, the diameter D1 is 100 mm or less, 80 mm or less, 50 mm or less, 30 mm or less, and / or 10 mm or less. Additionally or instead, the height H1 is, for example, 100 mm or less, 80 mm or less, 50 mm or less, 30 mm or less, and / or 10 mm or less. Fig. Figure 4B shows the dimensions of the stator 112' with the plastic casing 138 ( Fig. 4A), where H2 is a corresponding height of the stator 112' and D2 is a corresponding diameter of the stator 112'.

[0201] As in Fig. As shown in Figure 5, the magnetic drive and bearing device 110' can have several sensor units 140 for detecting a position Rz, Px, Py of the closure disk 106. The position Rz, Px, Py can be detected, for example, by detecting an offset in the x- and y-directions of the axis of rotation A relative to the closure disk 106. For clarity, only some of the sensor units 140 are labeled with a reference numeral in the figures. The sensor units 140 can be configured, for example, as eddy current sensors, capacitive sensors, and / or inductive sensors. Using the sensor units 140, a rotational position Rz of the closure disk 106 with respect to the rotation about the axis of rotation A can be detected. This also allows, for example, the detection of a rotation angle φ of the closure disk 106 and a position P. LThe opening 108 of the closure disc 106 and / or the angular frequency ω = dφ / dt of the closure disc 106 are detected and / or determined. The sensor units 140 can also be used to detect the x-position and y-position of the disc 106.

[0202] The sensor units 140 can, for example, be arranged alternately with the magnetic coils 118' along the third circumferential line around the axis of rotation A.

[0203] In the embodiment of Fig. 5 are the magnetic coils 118' for driving the disk 106 and the sensor units 140 for detecting a position Rz, Px, Py of the disk 106, which are different units from each other.

[0204] Alternatively, the magnetic coils 118 ( Fig. 3) for example, each may also be configured as actuator coils for magnetically driving the shutter disc 106 and as sensor units 140' for detecting a position Rz, Px, Py of the shutter disc 106.

[0205] The locking device 100 can include a control unit 142 for controlling a magnetic drive of the locking disk 106 and a magnetic bearing of the locking disk 106. The control unit 142 is, for example, part of the computing unit 104 ( Fig. 2) The control device 142 is specifically designed to control the magnetic drive of the closing disc 106 and the magnetic bearing of the closing disc 106 in a feedback control system based on acquired sensor data S A Position Rz, Px, Py of the shutter disc 106 is set up. The sensor data S A are, for example, from the sensor units 140, 140' ( Fig. 3, Fig. 5) recorded and transmitted to the regulatory unit 142.

[0206] In Fig. Figure 6 shows an exemplary control loop 300 for controlling the magnetic drive of the locking disk 106 and the magnetic bearing of the locking disk 106.

[0207] The control loop 300 is used to control the angular frequency ω (e.g., also the rotational speed) of the shutter disk 106 and to control the x-position Px and the y-position Py of the shutter disk 106. Optionally, the control loop 300 can also be used to control the rotational position Rz if the angular frequency is set to ω. In this case, the degrees of freedom Rx, Ry, and Pz are still passively stabilized.

[0208] In particular, an actual angular frequency ω is determined. IST (t) of the closure disc 106 is detected by means of a sensor 302 (e.g. the sensor units 140), fed negatively to a first comparison unit, with a predetermined target angular frequency ω SOLLA comparison is made, a first deviation e1(t) is determined and fed to a first control unit 304, and a first setpoint u1(t) is determined by means of the first control unit 304. An actuator 306 (drive and bearing unit 110) is then controlled based on the first setpoint u1(t) to adjust the angular frequency ω of the closing disk 106 to the predetermined target angular frequency ω SOLL to regulate.

[0209] In addition, an actual position Px is recorded. IST (t), P YIST (t) of the closure disc 106 is detected by means of the sensor system 302 (e.g. the sensor units 140), fed negatively to a second comparison unit, with a corresponding predetermined target position Px SOLL , Py SOLLThe first deviation is compared, a second deviation e2(t) is determined and transmitted to a second control unit 306, and a second setpoint u2(t) is determined by means of the second control unit 306. The actuator 306 (drive and bearing unit 110) is then controlled based on the second setpoint u2(t) to move the position Px, Py of the sealing disc 106 to the predetermined target position Px. SOLL , Py SOLL to regulate.

[0210] Reference number 308 in Fig. 6 designates a controlled section of the control loop 300, which comprises the sealing disc 106, the sensor system 302 (e.g., the sensor units 140), and the actuator system 306 (the drive and bearing unit 110). The first and second control units 304 and 306 are, in particular, part of the control device 142 ( Fig. 2).

[0211] The control device 142 thus enables precise control of the angular frequency ω (rotational speed) of the shutter disk 106 and the position Rz, Px, Py of the shutter disk 106 with respect to the three degrees of freedom Rz, Px, Py (i.e., rotation about the z-direction, translation in the x-direction, and translation in the y-direction). The remaining three degrees of freedom (i.e., rotation about the x-direction, rotation about the y-direction, and translation in the z-direction) are automatically and passively stabilized.

[0212] The control device 142 can also be configured to automatically balance the closing disc 106 by controlling the x-position Px and the y-position Py of the closing disc 106.

[0213] Furthermore, at least one acceleration sensor 143 (e.g. on the stator 112) can be provided, as shown by way of example in Fig. 5 shown). In this case, the control device 142 can be configured to balance the closing disk 106 based on data acquired from the at least one acceleration sensor 143.

[0214] As in Fig. As shown in Figure 7, the locking device 100 can optionally include a cooling device 144, 144', 144" for cooling the magnetic drive and bearing unit 110.

[0215] In a first variant, the cooling device 144 has a cooling ring 146 arranged around the closing disc 106 for dissipating heat.

[0216] In a second variant, the cooling device 144' has a cooling housing 148 arranged around the sealing disc 106 (e.g., closed) for dissipating heat. Fig. Figure 7 shows the cooling housing 148 not in a closed state for illustrative purposes.

[0217] In a third variant, the cooling device 144" has – in addition to or instead of the cooling ring 146 or the cooling housing 148 – a cooling tube 150 with a capillary structure 152 and a working fluid 154 (e.g., alcohol or another suitable liquid) contained within the cooling tube 150. The cooling tube 150 connects a space 156 around the sealing disc 106 or a space 156 around the drive and bearing assembly 110 with an external space 158.

[0218] Although the present invention has been described using exemplary embodiments, it can be modified in many ways. REFERENCE MARK LIST 1 Projection exposure system 2 Lighting system 3 light source 4 Lighting optics 5 object field 6 Object level 7 reticles 8 label holders 9 Reticle displacement drive 10 Projection optics 11 Image field 12 Image plane 13 wafers 14 wafer holders 15 wafer transfer drive 16 Lighting radiation 17 Collector 18 Intermediate focus plane 19 deflecting mirrors 20 first faceted mirror 21 first facet 22 second faceted mirror 23 second facet 24-camera setup 100 locking devices 102 Locking device 104 Computing equipment 106 Locking disc 108 Opening 110, 110' Drive and bearing unit 112, 112' Stator 114 inner edge 116 Magnet 118, 118' Magnet coil 119 gap 120 recess 121 wire winding 122 Indentation 123 wire 124 outer edge 125 Insulation material 126 Coverage area 128 rounded corner 130 Beam cross-sectional shape 132 Tolerance range 134 Iron core 136 plastic core 138 plastic material 140, 140' Sensor unit 142 Control device 143 Accelerometer 144, 144', 144" Cooling device 146 Cooling ring 148 Cooling cases 150 cooling pipe 152 Capillary structure 154 Working fluid Room 156 158 Outdoor space 200 vacuum housings 300 control loop 302 Sensors 304 Control unit 306 Control unit 308 Control section A axis of rotation B Magnetic force C gap width D1, D2 diameter E Main extent plane e1 deviation e2 deviation φ Angle of rotation H1, H2 height M1-M6 mirrors ω Angular frequency ω ISTAngular frequency ω SOLL Angular frequency Px, Py Position Px IST , Py IST position Px SOLL , Py SOLL Target position R direction Rz rotation position S A Sensor data S B Control signal S C Control signal U-shaped circumferential line u1 Setpoint u2 setpoint V vacuum

Claims

[1] Closure device (100) for a lithography system (1) and / or mask testing device (1), comprising a shutter disc (106) rotatably mounted about an axis of rotation (A) with at least one opening (108) spaced apart from the axis of rotation (A) for allowing working light (16) of the lithography system (1) or the mask test device (1) to pass through, and a magnetic drive and bearing device (110) by means of which the shutter disk (106) is rotatably mounted about the axis of rotation (A) and which is configured to drive the shutter disk (106) in a rotating manner about the axis of rotation (A), wherein the shutter disk (106) and the drive and bearing device (110) are configured to be arranged within a vacuum housing (200) of the lithography system (1) or the mask testing device (1), and the magnetic drive and bearing device (110) is configured to magnetically mount and drive the shutter disk (106) by means of a magnetic force (B) acting substantially radially on the shutter disk (106). [2] Locking device according to claim 1, wherein the magnetic drive and bearing device (110) has several magnets (116) provided on an inner edge (114) of the locking disk (106) and several magnetic coils (118) spaced apart from the locking disk (106) with the magnets (116), and the magnets (116) and the magnetic coils (118) are arranged to cooperate to provide a magnetic bearing and a magnetic drive of the locking disk (106). [3] A locking device according to claim 1 or 2, wherein the locking disk (106) forms a rotor of the drive and bearing unit (110), the locking disk (106) has a central recess (120) which has the axis of rotation (A), and the magnetic drive and bearing unit (110) has a stator (112) spaced apart from the locking disk (106) and arranged within the central recess (120). [4] Locking device according to claim 3, wherein the stator (112) has a diameter (D1) that is 100 mm or less, 80 mm or less, 50 mm or less, 30 mm or less and / or 10 mm or less, and / or the stator (112) has a height (H1) that is 100 mm or less, 80 mm or less, 50 mm or less, 30 mm or less and / or 10 mm or less. [5] Locking device according to any one of claims 1 to 4, wherein the magnetic drive and bearing device (110') has several sensor units (140) for detecting a position (Rz, Px, Py) of the closing disc (106), and / or the magnetic drive and bearing device (110) has several sensor units (140) for detecting a rotational position (Rz) of the closure disk (106) with respect to a rotation about the axis of rotation (A), an x-position (Px) with respect to a first direction (x) arranged perpendicular to the axis of rotation (A) and / or a y-position (Py) with respect to a second direction (y) arranged perpendicular to the first and to the axis of rotation (A). [6] A locking device according to any one of claims 1 to 5, wherein the magnetic drive and bearing device (110) has several magnetic coils (118) which are configured to interact with magnets (116) on the locking disk (106) for magnetic bearing and magnetic drive of the locking disk (106), and wherein the several magnetic coils (118) are each configured as a sensor unit (140') for detecting a position (Rz, Px, Py) of the locking disk (106). [7] A locking device according to any one of claims 1 to 6, comprising a control device (142) for regulating based on acquired sensor data (S A ) a position (Rz, Px, Py) of the shutter disk (106), a magnetic drive of the shutter disk (106) and / or a magnetic bearing of the shutter disk (106) such that an angular frequency (ω) of the shutter disk (106) is controlled with respect to a rotation about the axis of rotation (A), an x-position (Px) of the shutter disk (106) is controlled in a first direction (x) perpendicular to the axis of rotation (A) and / or a y-position (Py) of the shutter disk (106) is controlled in a second direction (y) perpendicular to the first (x) and to the axis of rotation (A). [8] Locking device according to claim 7, wherein the control device (142) is configured to automatically balance the locking disc (106) by controlling the x-position (Px) and the y-position (Py) of the locking disc (106). [9] Locking device according to claim 8, wherein the magnetic drive and bearing device (110) has at least one acceleration sensor, and the control device (142) is configured to balance the locking disk (106) based on data acquired by the at least one acceleration sensor. [10] Closure device according to one of claims 1 to 9, wherein the at least one opening (108) of the closure disc (106) is formed as at least one indentation (122) on an outer edge (124) of the closure disc (106). [11] Locking device according to any one of claims 1 to 10, wherein the shutter disc (106) has several of the openings (108) along a circumferential line (U) around the axis of rotation (A) and a covering area (126) of the shutter disc (106) is arranged between each two adjacent of the several openings (108) along the circumferential line (U) to cover the working light (16), and the cover area (126) has a rounded corner (128) when viewed from above parallel to the axis of rotation (A), and / or the working light (16) at the location of the shutter disc (106) has a beam cross-sectional shape (130) and a shape of the respective covering area (126) seen in a top view parallel to the axis of rotation (A) is designed such that the respective covering area (126) covers the beam cross-sectional shape (130) and a tolerance area (132) around the beam cross-sectional shape (130). [12] Locking device according to any one of claims 1 to 11, wherein the magnetic drive and bearing device (110) comprises several magnetic coils (118) which are configured to interact with magnets (116) on the closure disc (106) for magnetic bearing and magnetic drive of the closure disc (106), and the magnetic coils (118) each have a metal core (134), or the magnetic coils (118) each have a plastic core (136). [13] Locking device according to any one of claims 1 to 12, wherein the magnetic drive and bearing device (110) has several magnetic coils (118) which are configured to interact with magnets (116) on the closure disc (106) for magnetic bearing and magnetic drive of the closure disc (106), the magnetic coils (118) each have a wire winding (121) with a wire (123) which is sheathed with an insulating material (125), and the insulating material (125) comprises polytetrafluoroethylene, polyetheretherketone and / or a polyimide. [14] Locking device according to any one of claims 1 to 13, wherein the magnetic drive and bearing device (110) comprises several magnetic coils (118) which are configured to interact with magnets (116) on the closure disc (106) for magnetic bearing and magnetic drive of the closure disc (106), and the magnetic coils (118) are encased in a plastic material (138). [15] Locking device according to one of claims 1 to 14, comprising a cooling device (144, 144', 144") for cooling the magnetic drive and bearing assembly (110), wherein the cooling device (144, 144', 144") comprises: a cooling ring (146) arranged around the sealing disc (106) for dissipating heat, and / or a cooling housing (148) arranged around the closure disc (106) for dissipating heat, and / or a cooling tube (150) with a capillary structure (152) and a working fluid (154) contained inside the cooling tube (150), wherein the cooling tube (150) connects a space (156) around the sealing disc (106) with an outer space (158). [16] Lithography system (1) and / or mask testing device (1) with a closure device (100) according to one of claims 1 to 15 and a vacuum housing (200) for providing a vacuum (V), wherein the closure disk (106) and the drive and bearing device (110) of the closure device (100) are arranged inside the vacuum housing (200).

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