Module for semiconductor lithography and projection exposure system

Abstract

The invention relates to a module (30) for semiconductor lithography with a fluid channel (46) and an interface (32) for connecting a fluid line (40) to the fluid channel (46), wherein the interface (32) is closed with a sealing plug (50). According to the invention, the module (30) is characterized in that the sealing plug (50) comprises a drying device (54) for reducing the humidity in the fluid channel (46), wherein the drying device is designed as a cooling device (54).

Description

The invention relates to a module for semiconductor lithography and, in particular, to a projection exposure apparatus having such a module.Projection exposure apparatuses for semiconductor lithography are subject to extremely high demands on the imaging quality in order to be able to produce the desired microscopically small structures as free of defects as possible. In a lithography process or a microlithography process, an illumination system illuminates a photolithography mask, which is also referred to as a reticle. The light passing through the mask or the light reflected by the mask is projected by a projection optical unit onto a substrate (for example a wafer) which is coated with a photosensitive layer (photoresist) and is attached in the image plane of the projection optical unit, in order to transfer the structural elements of the mask onto the photosensitive coating of the substrate. The requirements for positioning the image on the wafer and the intensity of the light provided by the illumination system are increased with each new generation, resulting in a higher thermal load on the optical elements.In cases of high thermal load, it may be advantageous to temperature control certain modules, such as supporting frames, reference frames or optical modules, in particular in EUV projection exposure apparatuses, that is to say in apparatuses which are operated with electromagnetic radiation of the wavelength between 1 nm and 120 nm, in particular at 13.5 nm, by means of water cooling. Water-cooled modules can also be used in DUV projection exposure apparatuses, i.e. apparatuses which are operated with electromagnetic radiation having a wavelength between 120 nm and 300 nm. These modules comprise fluid channels through which temperature-controlled water typically flows, as a result of which the heat is carried away from the modules. The water is processed and provided by a water cabinet, wherein the water cabinet is connected to the module via fluid lines. The feed lines and discharge lines are frequently connected via flanges to an interface on the fluid channels formed in the module, wherein normally identical flanges are used in the entire projection exposure apparatus, i.e. are used, for example, both in the illumination system and in the projection optical unit.The flanges can be closed for the transport and / or storage of the modules, for which purpose a sealing element is introduced into the opening of the flanges. As a result, the fluid channel is sufficiently sealed with respect to the outside world, so that the latter is protected from contamination.Before a module is stored or transported, it passes through a method for drying the fluid channels, i.e. for removing the moisture from the fluid channel, in order to avoid corrosion of the fluid channel and of the interface. The method comprises pumping all fluid channels, which are partially divided into a plurality of circuits, down to very low pressures. The boiling temperature of water is only 22 degrees Celsius at pressures of approximately 1000 Pa, so that the residual water in the fluid channels evaporates and the water vapor can be suctioned off.However, the length, a large number of branches of the fluid channels and, in particular, the capillarity occurring in the fluid channels formed with very small diameters leads to the moisture not being able to be completely removed from the fluid channels within a reasonable time. This has the disadvantage that the residual moisture still present in the fluid channels balances itself over time in the entire fluid channel. In the region of the interface that is sufficiently dry after drying, conditions can thereby again occur which lead to condensation of the moisture and to subsequent corrosion in the region of the interface.Since the selection of material is greatly restricted, in particular for the use of components in an EUV projection exposure apparatus, on account of the very high requirements with respect to outgassing, a module can also have non-corrosion-resistant material, as a result of which corrosion can occur over time on account of the water present. This corrosion can lead to leakage at the interface and thus to failure of the module.The object of the present invention is to provide a device which eliminates the disadvantages of the prior art described above.This object is achieved by a device having the features of independent claim 1.A module for semiconductor lithography according to the invention has a fluid channel and an interface for connecting a fluid line to the fluid channel, wherein the interface is closed by a sealing plug. The module is characterized according to the invention in that the sealing plug comprises a drying device for reducing the air humidity in the fluid channel, wherein the drying device comprises a cooling device which advantageously reduces the residual moisture by condensation. The drying device thus makes it possible to prevent the residual moisture present in the fluid channels from condensing in the region of the interface and to reduce the residual moisture in the fluid channel over time or even to remove it completely.In particular, the drying device can project into the fluid channel. This has the advantage that the sufficiently dry environment remains unchanged during storage or the residual moisture can even be reduced further in the region of the interface by the drying method carried out before the sealing plug is introduced. The penetration depth and drying capacity is therefore expediently selected such that the increase in the residual moisture caused by diffusion from the fluid channel in the direction of the interface can be at least completely compensated for by the drying device.In particular, the cooling device can comprise a cooling element, which can be designed, for example, as a Peltier element.To improve the condensation performance, the cooling device may have a condensation enhancing surface. The reinforcing effect can be brought about in particular by an enlarged surface available for the condensation. This can be increased by a multiple compared to the ceramic usually used as a material for a Peltier element, for example, by a rough and / or porous surface. Furthermore, the material can have hygroscopic properties on the surface. For this purpose, the surface of the cooling element can be coated with a hygroscopic material, for example.The condensation enhancing surface can be formed in particular on an element connected to the cooling element via a thermally conductive element. The element can be designed, for example, as a jacket at least partially surrounding the cooling element, whereby a larger surface is brought about solely by the geometry.To absorb the water condensed on the cooling element, the cooling device can comprise a condensate guide. This can be designed, for example, as a drip-off channel, which is expediently arranged below the cooling element in the direction of gravity. Furthermore, the condensate guide can have an inclination with respect to the horizontal, as a result of which a discharge of the collected water is made possible.Furthermore, the cooling device can comprise a condensate collector. The water collected in the drip trough can be advantageously conducted by the inclination of the drip trough into the condensate collector designed as a collecting container. The sealing plug and all metallic parts are made of stainless steel, where appropriate, so that corrosion of the sealing plugs can be advantageously avoided.In a further embodiment, the drying device can comprise a moisture sensor, whereby the residual moisture in the fluid channel can be advantageously detected.In particular, the moisture sensor can be arranged in such a way that the moisture in the fluid channel is detected in the region of the interface. This allows, on the one hand, monitoring of the moisture in the region of the interface and, on the other hand, can be used for regulating the drying performance by the cooling element.Furthermore, the cooling device can comprise a sensor for detecting the amount of water collected in the cooling device. This makes it possible, for example, to detect and, if appropriate, to prevent any overflow of the collecting container that may occur.In a further embodiment, the drying device can have a marking on the outer side for aligning the drying device within the interface. In particular in the case of an embodiment with a drip channel and a collecting container as explained above, the alignment of the drying device with respect to the force of gravity is of decisive importance for the function of the drying device. The marking makes it possible to appropriately align the drying device during storage or transport, independently of the alignment of the interface and / or of the module.Alternatively or additionally, the drying device can comprise a hygroscopic material. The residual moisture is advantageously reduced by the absorption of the water by the hygroscopic material, which results in the advantage that the drying device can also be configured passively, that is to say it does not require an energy supply.A projection exposure apparatus according to the invention comprises a module according to one of the embodiments explained above.Exemplary embodiments and variants of the invention are explained in more detail below with reference to the drawings. They show FIG. 1 schematically in meridional section a projection exposure apparatus for EUV projection lithography, FIG. 2 is a schematic meridional section of a projection exposure apparatus for DUV projection lithography, FIG. 3 shows a schematic illustration of a detail of the projection exposure apparatus, FIG. 4 is a schematic illustration of the invention; and FIG. 5 is a schematic illustration of a detail of the invention.In the following, first of all, with reference to FIG. 1, the essential components of a projection exposure apparatus 1 for microlithography are described by way of example. The description of the basic structure of the projection exposure apparatus 1 and its components is not intended to be restrictive here.An embodiment of an illumination system 2 of the projection exposure apparatus 1 has, in addition to a radiation source 3, an illumination optical unit 4 for illuminating an object field 5 in an object plane 6. In this case, the illumination system does not include the light source 3.A reticle 7 arranged in the object field 5 is illuminated, and the reticle 7 is held by a reticle holder 8. The reticle holder 8 can be displaced in particular in a scanning direction via a reticle displacement drive 9.For the purpose of explanation, a Cartesian xyz-coordinate system is drawn in FIG. 1. The x-direction extends perpendicularly to the plane of the drawing. The y-direction runs horizontally and the z-direction runs vertically. The scanning direction runs along the y-direction in FIG. 1. The z-direction extends perpendicular to the object plane 6.The projection exposure apparatus 1 comprises a projection optical unit 10. the projection optical unit 10 serves for imaging the object field 5 into an image field 11 in an image plane 12. the image plane 12 runs parallel to the object plane 6.A structure on the reticle 7 is imaged onto a light-sensitive layer of a wafer 13 arranged in the region of the image field 11 in the image plane 12, the wafer 13 being held by a wafer holder 14. The wafer holder 14 is displaceable in particular along the y-direction via a wafer displacement drive 15. The displacement of the reticle 7 via the reticle displacement drive 9 on the one hand and of the wafer 13 via the wafer displacement drive 15 on the other hand can take place in synchronization with one another.The radiation source 3 is an EUV radiation source. The radiation 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 has in particular a wavelength in the range between 5 nm and 30 nm. The radiation source 3 can be a plasma source, for example an LPP (Laser Produced Plasma) source or a DPP (Gas Discharged Produced Plasma) source. It can also be a synchrotron-based radiation source. The radiation source 3 can be a free electron laser (FEL).The illumination radiation 16 emanating from the radiation source 3 is focused by a collector 17. The collector 17 can be a collector with one or more ellipsoidal and / or hyperbolic reflection surfaces. The illumination radiation 16 can be applied to the at least one reflection surface of the collector 17 in the grazing incidence (Grazing Incidence, GI), that is to say with angles of incidence greater than 45° with respect to the normal direction of the mirror surface, or in the normal incidence (Normal Incidence, NI), that is to say with angles of incidence less than 45°. The collector 17 can be structured and / or coated on the one hand for optimizing its reflectivity for the useful radiation and on the other hand for suppressing false light.After the collector 17, the illumination radiation 16 propagates through an intermediate focus in an intermediate focus plane 18. the intermediate focus plane 18 can represent a separation between a radiation source module, comprising the radiation source 3 and the collector 17, and the illumination optical unit 4.The illumination optical unit 4 comprises a deflection mirror 19 and, downstream thereof, a first facet mirror 20 in the beam path. The deflection mirror 19 can be a planar deflection mirror or alternatively a mirror having an effect influencing the beam beyond the pure deflection effect. Alternatively or additionally, the deflecting mirror 19 can be designed as a spectral filter which separates a used light wavelength of the illumination radiation 16 from false light of a wavelength deviating therefrom. If the first facet mirror 20 is arranged in a plane of the illumination optical unit 4 which is optically conjugate to the object plane 6 as a field plane, this is also referred to as a field facet mirror. The first facet mirror 20 comprises a multiplicity of individual first facets 21, which are also referred to below as field facets. Of these facets 21, only some are illustrated by way of example in FIG. 1.The first facets 21 can be designed as macroscopic facets, in particular as rectangular facets or as facets with an arcuate or part-circular edge contour. The first facets 21 can be embodied as planar facets or alternatively as convexly or concavely curved facets.As is known, for example, from DE 10 2008 009 600 A1, the first facets 21 themselves can also each be composed of a multiplicity of individual mirrors, in particular a multiplicity of micromirrors. The first facet mirror 20 can be designed, in particular, as a microelectromechanical system (MEMS system). For details, reference is made to DE 10 2008 009 600 A1.Between the collector 17 and the deflecting mirror 19, the illumination radiation 16 extends horizontally, i.e. along the y-direction.Arranged downstream of the first facet mirror 20 in the beam path of the illumination optical unit 4 is a second facet mirror 22. The second facet mirror 22 can also be arranged at a distance from a pupil plane of the illumination optical unit 4. In this case, the combination of the first facet mirror 20 and the second facet 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 U.S. Pat. No. 6,573,978.The second facet mirror 22 comprises a plurality of second facets 23. the second facets 23 are also referred to as pupil facets in the case of a pupil facet mirror.The second facets 23 can likewise be macroscopic facets, which can be round, rectangular or else hexagonally bordered, for example, or alternatively facets composed of micromirrors. In this respect, reference is likewise made to DE 10 2008 009 600 A1.The second facets 23 can have planar or alternatively convexly or concavely curved reflection surfaces.The illumination optics 4 thus form a double faceted system. This basic principle is also referred to as a honeycomb capacitor (Fly's Eye Integrator).It may be advantageous not to arrange the second facet mirror 22 exactly in a plane which is optically conjugate to a pupil plane of the projection optical unit 10. In particular, the pupil facet mirror 22 can be arranged tilted with respect to a pupil plane of the projection optical unit 10, as is described, for example, in DE 10 2017 220 586 A1.With the aid of the second facet mirror 22, the individual first facets 21 are imaged into the object field 5. The second facet mirror 22 is the last beam-forming mirror or indeed the last mirror for the illumination radiation 16 in the beam path in front of the object field 5.In a further embodiment of the illumination optics 4, not shown, a transmission optics can be arranged in the beam path between the second facet mirror 22 and the object field 5, which in particular contributes to the imaging of the first facets 21 into the object field 5. The transmission optics can have exactly one mirror, but alternatively also two or more mirrors, which are arranged one behind the other in the beam path of the illumination optics 4. The transmission optics can in particular comprise one or two mirrors for normal incidence (NI) mirrors and / or one or two mirrors for grazing incidence (GI) mirrors.In the embodiment shown in FIG. 1, the illumination optical unit 4 has exactly three mirrors downstream of the collector 17, namely the deflecting mirror 19, the field facet mirror 20 and the pupil facet mirror 22.In a further embodiment of the illumination optical unit 4, the deflecting mirror 19 can also be omitted, so that the illumination optical unit 4 can then have exactly two mirrors downstream of the collector 17, namely the first facet mirror 20 and the second facet mirror 22.The imaging of the first facets 21 by means of the second facets 23 or with the second facets 23 and a transmission optical unit into the object plane 6 is regularly only an approximate imaging.The projection optical unit 10 comprises a plurality of mirrors Mi, which are numbered according to their arrangement in the beam path of the projection exposure apparatus 1.In the example illustrated in FIG. 1, the projection optical unit 10 includes six mirrors M 1 to M 6. Alternatives with four, eight, ten, twelve or another number of mirrors Mi are also possible. The next-to-last mirror M 5 and the last mirror M 6 each have a passage opening for the illumination radiation 16. The projection optical unit 10 has an image-side numerical aperture which is greater than 0.5 and which can also be greater than 0.6 and which can be, for example, 0.7 or 0.75.Reflection surfaces of the mirrors Mi can be designed as free-form surfaces without a rotational symmetry axis. Alternatively, the reflection surfaces of the mirrors Mi can be designed as aspherical surfaces with exactly one axis of rotational symmetry of the reflection surface shape. The mirrors Mi, like the mirrors of the illumination optical unit 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.The projection optical unit 10 has a large object image offset in the y direction between a y coordinate of a center of the object field 5 and a y coordinate of the center of the image field 11.The projection optical unit 10 can be designed in particular anamorphically. It has in particular different imaging scales βx, βyin the x and y directions. The two imaging scales βx, βyof the projection optical unit 10 are preferably (βx, βy)=(+ / - 0.25, + / - 0.125). A positive imaging scale β means imaging without image reversal. A negative sign for the imaging scale β means image reversal imaging.The projection optical unit 10 thus leads to a reduction in the ratio 4:1 in the x-direction, that is to say in the direction perpendicular to the scanning direction.The projection optical unit 10 leads to a reduction of 8:1 in the y-direction, i.e. in the scanning direction.Other imaging scales are also possible. Identical and absolutely identical imaging scales in the x and y directions, for example with absolute values of 0.125 or of 0.25, are also possible.The number of intermediate image planes in the x- and y-direction in the beam path between the object field 5 and the image field 11 can be the same or can be different depending on the embodiment of the projection optical unit 10. Examples of projection optics with different numbers of such intermediate images in the x and y directions are known from US 2018 / 0074303 A1.In each case one of the pupil facets 23 is assigned exactly to one of the field facets 21 for forming in each case an illumination channel for illuminating the object field 5. This can result in particular in illumination according to the Kohler principle. The far field is divided into a plurality of object fields 5 with the aid of the field facets 21. The field facets 21 generate a plurality of images of the intermediate focus on the pupil facets 23 assigned to them in each case.The field facets 21 are imaged onto the reticle 7 in each case by an associated pupil facet 23 in a manner overlapping one another in order to illuminate the object field 5. The illumination of the object field 5 is in particular as homogeneous as possible. It preferably has a uniformity error of less than 2%. The field uniformity can be achieved by superimposing different illumination channels.By arranging the pupil facets, the illumination of the entry pupil of the projection optical unit 10 can be geometrically defined. By selecting the illumination channels, in particular the subset of the pupil facets which guide light, the intensity distribution in the entry pupil of the projection optical unit 10 can be adjusted. This intensity distribution is also referred to as illumination setting.A likewise preferred pupil uniformity in the region of sections of an illumination pupil of the illumination optical unit 4 that are illuminated in a defined manner can be achieved by redistribution of the illumination channels.Further aspects and details of the illumination of the object field 5 and in particular of the entry pupil of the projection optical unit 10 are described below.The projection optical unit 10 can have, in particular, a homocentric entry pupil. This can be accessible. It may also be inaccessible.The entrance pupil of the projection optical unit 10 cannot be illuminated exactly with the pupil facet mirror 22 as a rule. In an imaging of the projection optical unit 10, which images the center of the pupil facet mirror 22 telecentrically onto the wafer 13, the aperture beams often do not intersect at a single point. However, an area can be found in which the paired distance of the aperture beams becomes minimum. This surface represents the entry pupil or a surface in the spatial domain which is conjugated to it. In particular, this surface exhibits a finite curvature.It can be that the projection optical unit 10 has different positions of the entry pupil for the tangential and for the sagittal beam path. In this case, an imaging element, in particular an optical component of the transmission optics, should be provided between the second facet mirror 22 and the reticle 7. With the aid of this optical element, the different position of the tangential entry pupil and of the sagittal entry pupil can be taken into account.In the arrangement of the components of the illumination optical unit 4 illustrated in FIG. 1, the pupil facet mirror 22 is arranged in a surface conjugate to the entry pupil of the projection optical unit 10. The field facet mirror 20 is arranged tilted with respect to the object plane 6. The first facet mirror 20 is arranged tilted with respect to an arrangement plane which is defined by the deflecting mirror 19.The first facet mirror 20 is arranged tilted with respect to an arrangement plane which is defined by the second facet mirror 22.FIG. 3 shows a schematic illustration of a module 30 according to the prior art having a main body 31, wherein the main body 31 has a fluid channel 46. This is connected to a pipe 40 via an interface designed as a flange 32, the pipe 40 being connected to the flange 32 via a coupling 42.The flange 32 is arranged on a bearing surface 33 on the base body 31 and is connected to the latter by means of screws 34. The flange 32 further has a bore 41 with a diameter corresponding to the inner diameter of the tube 40.The coupling 42 has a nut 43 which is connected to the flange 32 via a thread 45 formed on the latter, a sealing element 44 being arranged on the end face of the flange 32.The base body 31 furthermore has a recess 35 which is conical at least in sections and in which a cylindrical sealing surface 36 is formed in the embodiment shown in FIG. 3. The flange 32 has a pin 37 with a geometry corresponding to the recess 35, wherein an O-ring 38 for sealing the flange 32 is arranged in a depression 39 in the region of the pin 37 opposite the sealing surface 36. The recess 35 in the base body 31 merges into the fluid channel 46.FIG. 4 shows a module 30 according to the invention with a sealing plug 50, which is arranged in a flange 32 explained in FIG. 3. The sealing plug 50 is inserted into the bore 41 in the flange 32 for storage and / or transport of the module 30 after disassembly of the tube 40 (FIG. 3 ) and after drying of the fluid channel 46 formed in the base body 31 of the module 30.For drying, the fluid channel 46 is flushed with extremely dry air or an oxygen-free gas mixture, such as nitrogen, until a predetermined air humidity has been established in the region of the flange 32.In the embodiment shown in Figure 4, the sealing plug 50 is connected to the nut 43 by a coupling 42 corresponding to the coupling 42 used to connect the tube 40 in Figure 3 and the seal 44 to the flange 32.The sealing plug 50 comprises a plug body 51 with a bore 53, wherein the plug body 51 is sealed with respect to the bore 41 in the flange 32 via O-rings 52.In the bore 53 of the plug body 51 a drying device designed as a cooling device 54 is arranged. By condensation, the moisture which occurs again as a result of the residual moisture in the fluid channel 46 as a result of saturation compensation effects over time, also in the region of the flange 32, is absorbed from the fluid channel 46, that is to say the latter is dried. Formation of condensate in the region of the flange 32 is thereby advantageously prevented. In the embodiment shown in the figure, the cooling device 54 has a cooling element designed as a Peltier element 55, it also being possible alternatively to use any other type of cooling element. The Peltier element 55 protrudes into the fluid channel 46 of the base body 31, as a result of which sufficient drying of the air at the flange 32 is ensured.As an alternative to air, the fluid channel 46 can also be filled with other oxygen-free gas mixtures or gases, such as nitrogen, for example. Even in cases of a reduced pressure present in the fluid channel 46, a sealing plug 50 with a drying device for drying in the region of the flange 32 is advantageous, since in this case too there is the possibility that water can condense on the flange 32.The water condensed on the Peltier element 55 drops due to gravity into a condensate guide, which is arranged below the Peltier element 55 in the direction of gravity and is designed as a drip channel 56. This has a gradient, so that the water flows into a condensate collector, which is designed as a collecting container 57 in the embodiment shown. The collecting container 57 is dimensioned such that the water condensed during the period of storage or transport can be completely absorbed, so that an overflow of the condensed water is advantageously avoided. Alternatively, the collecting container 57 can have a sensor 63 for detecting the fill level, as a result of which the latter can be monitored and emptied if necessary. The collecting container 57 can optionally have a valve or a storage medium which advantageously prevents the collected water from running out independently of the position in the space, for example during the handling of the module 30.Furthermore, an electronic system 58 necessary for the Peltier element 55 is arranged in the bore 53, wherein the latter is connected to a control system, not shown in FIG. 4, for the purpose of supplying energy and for the purpose of transmitting signals via one or more lines 59. Depending on the duration of the transport and in particular the storage of the module 30, a solution with a (rechargeable) battery is also conceivable.Optionally, the cooling device 54 can also have a moisture sensor 60, which is illustrated in FIGS. 4 and 5 by dashed lines. Like the Peltier element 55, it protrudes into the fluid channel 46 and detects the moisture in the region of the flange 32. Alternatively, the electronics 61 of the moisture sensor 60 can also be integrated into the electronics 58 of the Peltier element 55.The humidity sensor 60 serves to monitor the humidity of the air and, if necessary, can switch on the Peltier element 55 for drying or control or regulate the drying power.Alternatively to the sealing plugs 50 with cooling device 54 and sensor 60, sealing plugs are also conceivable which have only one sensor 60. These can be used in particular in the case of storage of the modules 30. In the event of a predetermined humidity being exceeded in the region of the flange 32, a warning signal can be triggered, for example, whereupon the module 30 is subsequently connected to an external drying installation. This can be used in series for a plurality of stored modules 30, which has a positive effect on the storage costs.The bore 53 in the sealing plug 50 is gas-tightly cast by a casting compound 62, such as an epoxy resin with amine hardeners and inorganic fillers.The stopper body 51 also has a marking designed as a notch 71 which serves to align the sealing stopper 50 with respect to the force of gravity in such a way that the function of the drip channel 56 and of the collecting container 57 is ensured.FIG. 5 shows a sectional illustration of the cooling device 54, wherein the sectional plane lies in the region of the fluid channel 46. The Peltier element 55 comprises, as is known, two ceramic elements 64, 65, which are connected to one another via thermoelectric elements 66. In the event of a current flow, heat is also transported through the thermoelectric element 66, in addition to the current. In the embodiment shown in FIG. 5, the current flow is formed such that the inner element 64 is heated and the outer element 65 is cooled.The cooling device 54 has a jacket 67 surrounding the Peltier element 55, which is connected to the cold element 65 of the Peltier element 55 via heat-conducting elements 68. The jacket 67 has a condensation-enhancing surface 69 on its outer side opposite the Peltier element 55. This is characterized by a comparatively large surface area, which is achieved, for example, by a certain roughness and / or porosity. The effect can be further enhanced by hygroscopic properties of the material used for the jacket 67 or by hygroscopic coating of the jacket 67 on the outside.The water 70 condensed on the surface 69 flows along the surface 69 in the direction of the drip channel 56 arranged under the jacket 67 due to the force of gravity, which is illustrated as arrow 72 in the figure, and drips into the latter. As already explained, the water 70 flows in the drainage channel 56 as far as the collecting container 57 because of the inclination of the latter.Alternatively, other solutions are also conceivable as drying devices, such as, for example, the attachment of a device with highly hygroscopic material, such as, for example, silicate or even a continuous flushing of the fluid channels with dry air.List of reference characters1 Projection exposure apparatus 2 Illumination system 3 Radiation source 4 Illumination optical unit 5 Object field 6 Object plane 7 Reticle 8 Reticle holder 9 Reticle displacement drive 10 Projection optical unit 11 Image field 12 Image plane 13 Wafer 14 Wafer holder 15 Wafer displacement drive 16 EUV radiation 17 Collector 18 Intermediate focus plane 19 Deflection mirror 20 Facet mirror 21 Facets 22 Facet mirror 23 Facets 30 Module 31 Basic body module 32 Flange 33 Contact surface 34 Screws 35 Cutout Basic body 36 Sealing surfaces Basic body 37 Pin flange 38 O-ring 39 Depression O-ring 40 Tube 41 Bore flange 42 Coupling 43 Nut 44 Seal 45 Thread flange / coupling 46 Fluid channel 50 Sealing plug 51 Plug body 52 O-rings 53 Bore Plug body 54 Cooling device 55 Peltier element 56 Drip trough 57 collecting container 58 electronics cooling element 59 line 60 sensor 61 sensor electronics 62 potting compound 63 sensor water level 64 first region (warm) 65 second region (cold) 66 thermoelectric element 67 jacket 68 heat conducting elements 69 condensation enhancing surface 70 water 71 marking sealing plugs 72 gravity 101 projection exposure apparatus 102 illumination system 107 reticle 108 reticle holder 110 projection optics 113 wafer 114 wafer holder 116 DUV radiation 117 optical element 118 mounts 119 objective housing M 1-M 6 mirrorReferences included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedDE 10 2008 009 600 A1 [0035, 0039]US 2006 / 0132747 A1

[0037] EP 1 614 008 B1

[0037] U.S. Pat. No. 6,573,978

[0037] DE 10 2017 220 586 A1

[0042] US 2018 / 0074303 A1

[0056]

Claims

Module (30) for semiconductor lithography, having a fluid channel (46) and an interface (32) for connecting a fluid line (40) to the fluid channel (46), wherein the interface (32) is closed by a sealing plug (50), wherein the sealing plug (50) comprises a drying device (54) for reducing the air humidity in the fluid channel (46), characterized in that the drying device is designed as a cooling device (54).Module (30) according to Claim 1, characterized in that the drying device (54) projects into the fluid channel (46).Module (30) according to claim 1 or 2, characterized in that the cooling device (54) comprises a cooling element (55).Module (30) according to Claim 3, characterized in that the cooling element is designed as a Peltier element (55).Module (30) according to one of the preceding claims, characterized in that the cooling device (54) has a condensation-enhancing surface (69).Module (30) according to claim 5, characterised in that the condensation enhancing surface (69) is formed on an element (67) connected to the cooling element (55) via a thermally conductive element (68).Module (30) according to one of the preceding claims, characterized in that the cooling device (54) comprises a condensate guide (56).Module (30) according to one of the preceding claims, characterized in that the cooling device (54) comprises a condensate collector (57).Module (30) according to one of the preceding claims, characterized in that the drying device (54) comprises a moisture sensor (60).Module (30) according to Claim 9, characterized in that the moisture sensor (60) is arranged in such a way that the moisture in the fluid channel (46) is detected in the region of the interface (32).Module (30) according to any one of the preceding claims, characterized in that the cooling device (54) comprises a sensor (63) for detecting the quantity of water collected in the cooling device (54).Module (30) according to one of the preceding claims, characterized in that the drying device (54) has on the outside a marking (71) for aligning the drying device (54) within the interface (32).Module (30) according to one of the preceding claims, characterized in that the drying device (54) comprises a hygroscopic material.Projection exposure apparatus (1, 101) for semiconductor lithography, having a module (30) according to one of Claims 1 to 13.

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