Classifications

• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D1/00—Electroforming
  • C25D1/06—Wholly-metallic mirrors
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B82—NANOTECHNOLOGY
  • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
  • B82Y10/00—Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
  • C23C14/0005—Separation of the coating from the substrate
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
  • C23C28/02—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D only coatings only including layers of metallic material
  • C23C28/023—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D only coatings only including layers of metallic material only coatings of metal elements only
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
  • C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
  • C23C28/32—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer
  • C23C28/322—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer only coatings of metal elements only
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
  • C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
  • C23C28/34—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates
  • C23C28/345—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates with at least one oxide layer
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
  • C23C28/40—Coatings including alternating layers following a pattern, a periodic or defined repetition
  • C23C28/42—Coatings including alternating layers following a pattern, a periodic or defined repetition characterized by the composition of the alternating layers
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D7/00—Electroplating characterised by the article coated
  • C25D7/08—Mirrors; Reflectors
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B17/00—Systems with reflecting surfaces, with or without refracting elements
  • G02B17/02—Catoptric systems, e.g. image erecting and reversing system
  • G02B17/06—Catoptric systems, e.g. image erecting and reversing system using mirrors only, i.e. having only one curved mirror
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B5/00—Optical elements other than lenses
  • G02B5/08—Mirrors
  • G02B5/0816—Multilayer mirrors, i.e. having two or more reflecting layers
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B5/00—Optical elements other than lenses
  • G02B5/08—Mirrors
  • G02B5/0891—Ultraviolet [UV] mirrors
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
  • G03F7/20—Exposure; Apparatus therefor
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
  • G03F7/70—Microphotolithographic exposure; Apparatus therefor
  • G03F7/70058—Mask illumination systems
  • G03F7/7015—Details of optical elements
  • G03F7/70166—Capillary or channel elements, e.g. nested extreme ultraviolet [EUV] mirrors or shells, optical fibers or light guides
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
  • G03F7/70—Microphotolithographic exposure; Apparatus therefor
  • G03F7/708—Construction of apparatus, e.g. environment aspects, hygiene aspects or materials
  • G03F7/7095—Materials, e.g. materials for housing, stage or other support having particular properties, e.g. weight, strength, conductivity, thermal expansion coefficient
  • G03F7/70958—Optical materials or coatings, e.g. with particular transmittance, reflectance or anti-reflection properties
• • G—PHYSICS
  • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
  • G21K—TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
  • G21K1/00—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating
  • G21K1/06—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating using diffraction, refraction or reflection, e.g. monochromators
  • G21K1/062—Devices having a multilayer structure
• • G—PHYSICS
  • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
  • G21K—TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
  • G21K2201/00—Arrangements for handling radiation or particles
  • G21K2201/06—Arrangements for handling radiation or particles using diffractive, refractive or reflecting elements
  • G21K2201/061—Arrangements for handling radiation or particles using diffractive, refractive or reflecting elements characterised by a multilayer structure
• • G—PHYSICS
  • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
  • G21K—TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
  • G21K2201/00—Arrangements for handling radiation or particles
  • G21K2201/06—Arrangements for handling radiation or particles using diffractive, refractive or reflecting elements
  • G21K2201/064—Arrangements for handling radiation or particles using diffractive, refractive or reflecting elements having a curved surface
• • G—PHYSICS
  • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
  • G21K—TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
  • G21K2201/00—Arrangements for handling radiation or particles
  • G21K2201/06—Arrangements for handling radiation or particles using diffractive, refractive or reflecting elements
  • G21K2201/067—Construction details
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T29/00—Metal working
  • Y10T29/49—Method of mechanical manufacture
  • Y10T29/4981—Utilizing transitory attached element or associated separate material
  • Y10T29/49812—Temporary protective coating, impregnation, or cast layer

Definitions

• the invention relates to a method for producing an optical element by molding, an optical element produced by such a method, a collector shell, in particular for a grazing-incidence collector for use, in particular in EUV radiation in the wavelength range of 4 to 30 nm, preferably from 7 to 15 nm. Furthermore, the invention relates to a microlithography projection exposure apparatus, in particular also an illumination system of such a microlithography projection exposure apparatus.
• Optical elements for example for microlithography systems, have hitherto been produced, for example, by vapor deposition on prefabricated substrates. This is described for example in DE 10 2005 017 742 A1.
• DE 10 2005 017 742 A1 At least the optically active coating is deposited on a substrate.
• Such methods are on the one hand very expensive, on the other hand for coating, for example, in closed areas unsuitable.
• a disadvantage of the systems for example from DE 10 2005 017 742 A1, was that the substrates were non-conductors which could charge electrostatically, for example, when installed in an illumination system.
• Collectors for illumination systems having a wavelength preferably ⁇ 126 nm, particularly preferably wavelengths in the EUV range of 4 to 30 nm, in particular at 7 nm or at 13.5 nm for receiving the from a light source radiated light and for illuminating a region in a plane with a plurality of rotationally symmetrical mirror shells, which are arranged one inside the other about a common axis of rotation, are known in a variety of designs.
• US 5,763,930 shows a nested collector for a pinch-plasma light source, which serves to collect the radiation emitted by the light source and to focus in a light guide.
• the document US 6,285,737 B1 discloses a lighting system with a grazing-incidence collector mirror.
• the collector mirror comprises a plurality of individual mirrors in a stacked arrangement.
• the individual mirror surfaces of the stack do not form a contiguous surface, in particular no closed surface such as, for example, a surface of revolution.
• a surface of revolution is an area obtained by rotating about an axis of rotation of a curve lying in a plane including the axis of rotation.
• the individual mirrors of the stacked mirror array according to US Pat. No. 6,285,737 B1 consist of a base layer which forms the base body and is coated with a reflection layer of, for example, rhodium, molybdenum, gold or other alloys.
• the single mirror is coated with ruthenium.
• the application of the individual layers is carried out by a vapor deposition or a sputtering method, d. H. with conventionally known methods on a base body.
• the thickness of the metal layer forming the reflection layer is very large, in particular more than 100 nm, in order to be resistant to the thermal influences due to the arrangement with respect to the light source. After vapor deposition, the layer is optically polished.
• the mirror shells thus formed have either flat, elliptical or aspherical surfaces.
• the ruthenium coated single mirrors reflect 50-84% of EUV radiation when the angle of incidence to the surface normal is 75 to 80 °, i. H. the mirror is operated under grazing incidence.
• collectors As an alternative to the collector system of an array with stacks of individual mirrors, as described in US 6,285,737, you can also collectors with closed surfaces, for example, use surfaces of revolution in illumination systems for EUV lithography. Such collectors have become known, for example, from US Pat. No. 7,091,505, US 2003-0043455A1, US Pat. No. 7,015,489 US 2005 / 023645A1, US 2006-0097202 A1 or EP 1225481.
• the collectors with closed mirror shells described in the aforementioned documents are preferably designed as systems with a plurality of closed mirror shells arranged one inside the other and are referred to as so-called nested collectors.
• Closed mirror shells are, for example, annular closed mirror surfaces.
• the collector shells which are formed as closed surfaces, for example as surfaces of revolution, either have the disadvantage of a low reflectivity of the incident light or are unstable and prone to deformation under thermal stress, as they occur in particular in EUV systems.
• the invention is therefore based on the object in a first aspect
• a layer system comprising in the first method, at least one separation layer system and a reflective layer system, in the second method, a separation layer system without reflective layer system, deposited.
• the main body is formed on the layer system by electroforming, in particular an electrochemical process.
• the detachment of the optical element, for example, the collector shell on the release layer system from the impression takes place.
• an evaporation step for the reflection layer system follows in the second method, in the first method the optical element, for example the collector shell, has already been completed.
• the problem of the molding process consists in finding a suitable separating layer system which allows taking into account the existing layer stresses an impression without influencing the optimal optical properties of the reflection layer (in the first method) and maintaining the mechanical stability of the individual layers.
• PVD Physical Vapor Deposition
• thermal evaporation, evaporation with electron beam evaporators or sputtering, in particular sputtering with magnetron sources are used as the coating method.
• the evaporation source is positioned below the impression body to be coated.
• a sufficiently homogeneous layer thickness can be achieved on the one hand by a large distance between source and impression body on the other hand by simultaneous evaporation using a plurality of uniformly arranged sources.
• the sources When using sputtering techniques, the sources must be evenly spaced near the surface of the molded article to be coated, due to the high sputtering gas pressure required in this process.
• An optimal layer thickness homogeneous technik can by one of the form of the
• the vapor deposition of the evaporation surface facing away from the surface of the molded article to be coated can be done for example by rotation of the Abform stressess during the coating process.
• the subsequent coating of already molded optical elements is carried out during sputtering, as already explained, with a plurality of sources arranged equidistant or with a source adapted to the shape of the impression body.
• a plurality of sources arranged equidistant or with a source adapted to the shape of the impression body.
• thermal sources or electron beam evaporator the use of glare techniques allows a uniform coating thickness distribution over the entire surface of the optical element.
• An inventive impression-layer system for the production of optical elements for example collector shells for grazing-incidence collectors, under which the entirety of Abform stresses, release layer system, layer system and the base body forming base layer before the impression, ie separation comprises, is for the first embodiment of an inventive optical element, in particular collector shell characterized by the sequence of Abform analyses and layers of silicon dioxide SiO 2, gold Au and galvanized, for example, at collectors ruthenium Ru 1 nickel Ni.
• the second alternative embodiment of the optical element, for example the collector shell is characterized by a sequence of molded articles and layers of SiO 2 , Ru, Cr, Ru, Cr, Ni and galvanized Ni in the case of a grazing-incidence collector.
• optical elements in which the light is reflected in grazing incidence that is, under grazing-incidence
• Grazing-incidence reflection is preferably understood as meaning a reflection in which the reflection angle is more than 70 degrees to the normal, which is perpendicular to the reflecting surface.
• a normal-incidence reflection is preferably understood to be a reflection in which the reflection angle is less than 30 degrees to the normal, which is perpendicular to the reflective surface.
• a normal-incidence optical element for example a normal-incidence mirror
• the mirror surface in a particular embodiment of a multi-layer system, for example, a multi-layer system of Mo / Be alternating layers or Mo / Si alternating layers.
• a multi-layer system for example, a multi-layer system of Mo / Be alternating layers or Mo / Si alternating layers.
• layer systems comprise more than 40, preferably more than 60 such alternating layers.
• the incident light is reflected substantially normal-incidence, that is, at angles ⁇ 30 degrees, to the surface normal.
• Optical elements which are operated under normal incidence may be normal-incidence collector mirrors or, in particular, facet mirrors, for example field facet mirrors or pupil facet mirrors, as are known from US Pat. No. 6,658,084 B2 or US 2006/0 132 747 A1.
• a faceted optical element for example a field facet mirror, can comprise 72 field facets which are applied to a mirror support or a substrate. Each individual mirror facet acts as a normal-incidence mirror.
• the separating layer system comprises an SiO 2 layer deposited on the molding body and an Au layer deposited on Si 2 O 2 .
• the detachment of the optical element, for example, the collector shell takes place with an additional Au layer from the Abform stresses between the SiO 2 - and Au surface in the separation layer system.
• Au is detached from the reflection layer, preferably chemically.
• the separation takes place directly between the layer system of the collector shell and SiO 2
• a conditioning step is provided.
• the SiO 2 layer is exposed to a surface treatment after deposition over a predefined period of time.
• the layer system is then deposited directly on the SiO 2 layer.
• layers of ruthenium and an adhesion layer of chromium may preferably be deposited alternately. The separation takes place in such systems between the SiO 2 and the Ru surface.
• the optical element is produced quasi from the inside to the outside.
• the production from the inside to the outside has the advantage that also collector shells with closed surfaces and small diameters, preferably diameter d ⁇ 200 mm, can be produced.
• Another advantage, in particular in the case of normal-incidence facet mirrors, is the ease of manufacture.
• the optical element can also be produced by molding the base body and subsequent coating. Again, there is the provision of a Abform stresses, with a surface that corresponds to the geometry of the optical element. If the optical element is a collector shell, the surface corresponds to the inner wall of the
• the main body is molded on the impression body, preferably by an electrochemical process. Subsequently, the main body is detached from the impression body. Time-shifted and with other equipment is then the deposition of a layer system.
• the system comprises at least one reflective layer which is applied to the surface of the base body. This is also done by thermal evaporation, electron beam evaporation or sputtering.
• An impression layer system for example for the production of collector shells by molding the base body and subsequent coating is characterized by the sequence of Abform stresses and layers of silicon dioxide SiO 2 , gold Au or palladium Pd as a release layer system. Ruthenium Ru can subsequently be applied by vapor deposition.
• the coating of the reflection layer system consisting of at least one Ru layer or a Mo / Si or Mo / Be multi-layer system, as already stated with several equally spaced sources or with the shape of the Abform stressess adapted source executed.
• Electron beam evaporator the inner surface of the collector shell is subsequently coated with the use of glare techniques with Ru.
• a collector dish is preferably used in a grazing-incidence collector.
• a collector comprises not only a single rotationally symmetrical shell or rotary shell, but a plurality of such rotationally symmetrical collector shells, wherein the rotation shells are arranged one inside the other around a common axis of rotation.
• the collector is designed with at least two collector shells arranged one inside the other, preferably four, six, eight or ten collector shells. This is part of an illumination system for the EUV wavelength range, in which the optical radiation is recorded at an angle greater than 70 ° to the surface normal. In such a case, it is a grazing-incidence collector.
• Grazing-incidence collectors have the advantage over normal-incidence collectors that they degrade only to a small extent due to the debris of the source, ie they hardly lose their reflectivity. Furthermore grazing incidence collectors are always simpler structure, since they usually have only an optical coating. With these, reflectivities> 80% can be achieved with lower surface roughness requirements.
• a collector shell as a grazing-incidence element
• a normal-incidence element for example a facet mirror or an imaging mirror or a normal-incipient collector mirror
• an impression body made of a suitable material, for example quartz glass or kanigienized aluminum, is first produced and superpolished.
• the superpolishing reduces the surface roughness of the molded body or sample body, also referred to as a mandrel, to values corresponding to those required by a conventional multilayer system coated normal-incidence optical element in order to achieve high
• Such roughnesses are preferably in the range of 0.2 nm HSFR.
• the roughness HSFR denotes the RMS roughness at spatial frequencies between 10 nm and a few ⁇ m.
• the impression body After the superpolishing of the impression body, the impression body is provided with a coating.
• a coating may be, for example, a 50 to 200 nm thick gold layer.
• a metal layer for example a nickel or copper layer, is grown on the 50-200 nm-thick conductive gold layer with the aid of galvanic methods.
• the gold layer serves as a cathode.
• the gold layer with the metal layer deposited thereon for example the nickel layer, is separated and a Mo / Si multilayer layer with a Ru covering layer is grown on this separated layer.
• the production of a facet or of a normal-incidence element with molding techniques can also be carried out by applying a Ru layer to the mandrel and a multilayer system of Mo / Si on the Ru layer.
• the substrate layer for example, nickel Ni or Cu copper is grown galvanically.
• the last layer of the multilayer system is a conductive Mo layer which can serve as a cathode in such a process.
• the Mo layer can be designed correspondingly thick.
• Substrate layer of the optical element using the molding process during the galvanic deposition of the substrate support cooling channels or cooling lines are introduced. These cooling lines are used for the molding of the high absorbed heat energy, which can be, for example, between 3 and 5 watts per facet for a faceted element.
• the cooling takes place with the aid of a liquid medium, for example water.
• To galvanize the cooling elements into the substrate surface first about 0.5 mm thick metal layer, for example of nickel or copper, grown on the metal layer connected to the mandrel. After growing a first part of the metal layer serving as the substrate layer, the cooling elements, in particular the cooling line, are then positioned. After the cooling lines are positioned, metal is further deposited by galvanic means, so that the cooling lines are firmly and materially embedded in the substrate surface. By embedding the cooling line in the substrate layer in particular a low heat transfer resistance is ensured.
• the optical element or a part of the optical element is separated from the mandrel by a temperature shock.
• the entire unit of mandrel and optical element is subjected to a temperature jump, typically to lower temperatures. Due to the different coefficients of thermal expansion of mandrel and the materials of the grown optical element, a separation between the mandrel and the grown optical element or part of the optical element occurs as soon as the thermally induced stresses exceed the adhesive stresses between the layers of the optical element and the mandrel.
• a gold layer can serve as the gold remains on the separated metal body constituting the substrate.
• Ru can also serve as a separating layer, especially in grazing-incidence components.
• a grazing-incidence component for example a grazing-incidence mirror, preferably a grazing-incidence collector, in particular with closed
• a grazing-incidence component for example a grazing-incidence mirror, preferably a grazing-incidence collector, in particular with closed
• collectors are to be specified, which are characterized by a high stability.
• Collector cups which are preferably designed as annular closed mirror surfaces, for example, as a rotation surfaces, to be provided with ruthenium as a reflection layer.
• the geometric dimension of a collector shell are chosen such that it is characterized by a length I of> 120 mm. If the collector shell is not a closed surface but, for example, a partially perforated surface, instead of the diameter, the vertical distance (d / 2) of the end point from a straight line along which the length of the collector shell is defined.
• the vertical distance d / 2 is ⁇ 375 mm, preferably ⁇ 150 mm, in particular ⁇ 100 mm, particularly preferably ⁇ 75 mm, very particularly preferably ⁇ 50 mm.
• the distance d / 2 is between 40 mm and 375 mm, in particular between 40 mm and 135 mm, particularly preferably between 40 mm and 75 mm.
• the collector shells according to the present invention are so-called rotary shells.
• Rotational trays are trays obtained by rotating plane curves around an axis of rotation, with both the axis of rotation and the plane curve lying in one plane. Examples for
• Rotary dishes are cylindrical dishes, spherical dishes or bowls.
• the plane curve is a parallel to the axis of rotation
• the plane curve is a semicircle with the center on the axis of rotation and cone shells a straight line that intersects the axis of rotation.
• characteristic sizes for the collector shells is in present application whose length I and the diameter d or half the diameter, ie the radius taken.
• the length I means the length of the plane curve from a start to an end point.
• the collector shell viewed in the longitudinal direction of the axis of rotation, has an initial and an end point.
• the starting point is the point of the shell closest to the light source, the end point being the point of the shell farthest from the light source.
• the distance between the light source and the starting point is also referred to as the starting distance. This is smaller than the distance of the end point viewed from the light source in the longitudinal direction of the optical axis.
• the vertical distance of the starting point from the rotation axis is also referred to as the first radius or ra and the distance of the end point as the second radius re.
• the diameter d is defined over the radius of the end point re.
• the length (I) along the rotation axis is> 120 mm and the diameter d ⁇ 750 mm, in particular d ⁇ 300 mm, in particular ⁇ 200 mm, in particular ⁇ 150 mm, particularly preferably ⁇ 100 mm.
• the diameters of the mirror shells are in the range 80 mm to 750 mm, preferably in the range 80 mm to 270 mm, particularly preferably in the range 80 mm to 150 mm.
• the inventors have recognized that particularly good imaging properties can be achieved by the coating comprising Ru on a metal base body.
• a high stability is achieved. Further, by using a plurality of such nested cups to a nested collector, a high collection aperture with a small number of trays can be achieved. Furthermore, in a developed embodiment, a high efficiency is achieved by the selected minimum length I ⁇ 120 mm.
• the collector shells comprise a base body, preferably of a metal and a layer system, which is arranged on the base body is.
• the layer system comprises at least the reflection layer forming an optical surface.
• the layer system according to a first embodiment comprises only the reflective layer.
• the main body is preferably made of a metal, preferably galvanized nickel. As further materials, copper and ruthenium are conceivable for the main body or a sequence of these materials and also mixtures.
• the layer thickness of the reflection layer made of ruthenium is preferably between in each case including 10 nm to 150 nm, preferably 10 nm to 120 nm, particularly preferably 15 nm to 100 nm, very particularly preferably between 20 and 80 nm.
• 10 nm to 150 nm preferably 10 nm to 120 nm, particularly preferably 15 nm to 100 nm, very particularly preferably between 20 and 80 nm.
• the layer system is designed as a multilayer system comprising in each case the components ruthenium and chromium, which are arranged alternately in layers.
• the coating parameters such as layer thicknesses, layer thickness ratios between the individual layers, bedampfger ngsraten and other process parameters at the deposition, in particular the vapor deposition of the individual layers are optimized and adjusted or controlled with respect to the desired result.
• the multilayer system is formed in detail by a first ruthenium layer forming the optical surface and a second ruthenium layer.
• An adhesive layer is provided between the first and second ruthenium layers. This is preferably made of chrome.
• a metallic intermediate layer which is preferably made of the same metal as the base layer forming the base layer.
• the intermediate layer will preferably also consist of nickel.
• the layer thickness of nickel is preferably ⁇ 30 nm.
• the adhesive layers have no further function, so that layer thicknesses in the range between 1 and 5 nm inclusive, preferably 1 to 2 nm, can be considered sufficient here. These are preferably formed from chromium.
• the layer thickness of the first ruthenium layer is 5 to 20 nm, preferably 8 to 12 nm.
• the second ruthenium layer is characterized by a layer thickness which is between 20 to 80 nm, preferably between 30 and 60 nm.
• the embodiments of the collector shell are characterized by a microroughness in the range of less than 2 nm RMS at a wavelength of 13 nm at the optical surfaces.
• the collector shells thus have a sufficiently high reflectivity.
• the geometric design of the collector shell takes place as a rotation shell, d. H. as a rotationally symmetrical body with respect to a rotational or rotational symmetry axis.
• the collector shells are therefore closed surfaces.
• the axis of rotation corresponds to the optical axis OA of the collector shell.
• the single collector shell is preferred as aspheric segment with
• the mirror shells are a rotation dish of an ellipsoid, a paraboloid or a hyperboloid.
• a paraboloid results in a completely parallel beam and thus a lying at infinity light source.
• Collectors with rotating bowls whose plane curves are sections of hyperboloid lead to a divergent beam and are of particular interest when the collector should be as small as possible.
• the molding method according to the invention is used in grazing-incidence components to provide cooling devices.
• a first layer of a metal for example a nickel or a copper layer is first electrodeposited onto the conductive layer, for example the gold layer having a thickness of 50-200 nm, which has been applied to the impression body, ie the mandrel, the gold layer being deposited as Cathode serves.
• cooling and / or structural elements such as cooling pipes or bearing elements are positioned on the surface of the grown metal layer.
• a further second layer of metal consisting of nickel or copper, is then electrodeposited in such a way that the cooling and structural elements are firmly and materially embedded in the substrate.
• the first layer is between 0.1 and 1 mm thick and the second layer between 1 and 4 mm.
• a reflective normal-incidence element may be a mirror used, for example, in an imaging system such as a projection objective.
• normal-incidence elements may, for example, also be normal-incidence collector mirrors.
• the normal-incidence element is single facets of a faceted optical element.
• Such faceted optical elements having a multiplicity of individual facets, for example field facets or pupil facets, have become known from US Pat. No. 7,006,595.
• the faceted optical element shown in US Pat. No. 7,006,595 comprises, for example, 216 field facets as well as many pupil facets.
• the release layer system may be a metal layer deposited on the impression body, for example an Au layer or a Ru layer.
• the main body of the reflective normal-incidence element can then be galvanically grown on this layer and serves as the cathode.
• a metal on the separation layer for example of nickel or copper by electroplating can be done in two steps.
• a first layer thickness for example in the range of 0.1 to 0.8 mm, preferably 0.5 mm of nickel or copper on the gold layer, which is applied to the impression body, are deposited. Then it is possible to position structural elements or cooling elements which are to be introduced into the basic body.
• a second layer of metal for example nickel or copper, is electrodeposited.
• the cooling lines or bearing elements are thus firmly and materially introduced into the electrodeposited body. As a result, in particular a low heat transfer resistance is ensured.
• the main body can be separated from the impression body by a temperature shock.
• a further step can then on the separated body a multilayer system for the reflective normal-incidence element, for example consisting of Mo / Si are applied.
• the uppermost Mo layer would then form the electrode for the electrodeposition.
• the uppermost Mo layer is formed correspondingly thick.
• an electrode layer for example in the form of a metal layer, e.g. a gold Au layer or a nickel Ni layer can be applied to the multilayer system.
• the complete normal-incidence element including the multiple layer system deposited on it, can then be separated from the impression body.
• the normal-incidence elements produced by means of molding techniques according to the invention are characterized in particular by a base body consisting of a metal such as nickel or copper, and a separating layer arranged between the multiple-layer system and the base body, for example consisting of Au and one Cover layer arranged above the multilayer system, for example a Ru layer. Furthermore, mechanical components such as joint adapters or even cooling elements such as cooling tubes can be introduced very easily into the molded metal body.
• FIG. 1 shows, in a highly schematically simplified representation, a first embodiment of a grazing-incidence element according to the invention, in this case a collector shell;
• FIGS. 2a-b illustrate two further geometric embodiments of collector shells;
• FIG. 3 illustrates a second embodiment of a collector shell
• FIG. 4a - b illustrate schematically simplified the structure of a
• FIGS. 4c -4d illustrate the impression on the basis of signal flow images
• FIG. 5 shows, on the basis of a diagram, the influence of the detachment time for the Au layer on the roughness
• Fig. 6a-b illustrate a molding layer system for collector shells according to a second embodiment before and after the separation in
• FIG. 7 illustrates the
• Figures 8a-b illustrate a magnetron sputtering apparatus for making the coatings of the first and second embodiments
• Figure 9 illustrates a system for sputtering the reflection layer on the
• FIG. 10 shows, on the basis of a section of an illumination system, a collector with collector shells designed according to the invention:
• FIGS. 11a-c illustrate by way of example exemplary possible values for roughness and reflections based on diagrams;
• Fig. 12a - g first possibility of the production of normal-incidence elements by means of a molding process
• FIG. 13 a - h second possibility of producing normal-incidence elements with the aid of a molding method: FIG.
• Fig. 14a-h third way of producing normal-incidence elements by means of a molding process.
• FIG. 1 illustrates, in a schematically simplified representation, the basic structure of a first embodiment of a grazing-incidence element, for example a collector shell 1, produced, for example, by means of molding techniques on the basis of a section in the z-x plane.
• a collector shell This is designed as a rotationally symmetric element.
• the z-axis is defined by the optical axis OA, which corresponds to the rotational symmetry axis RA.
• the collector shell is produced as a rotation shell by rotation of the curve K, which is planar in section in the z-x plane, about the rotational symmetry axis RA.
• the z-x plane containing the rotational symmetry axis RA is also referred to as the meridional plane.
• the following reference symbols are defined in the coordinate system zx with respect to the optical axis OA: a starting point e endpoint z (a) z-coordinate of the starting point of the collector shell z (e) z-coordinate of the end point of the collector shell x (a) x-coordinate of the Start point x (e) x-coordinate of the end point
• the starting point a defines in the coordinate system the first end region 2 of the collector shell 1, also referred to as the object-side or input-side end region, and the end point b the second end region 3, which is also referred to as the image-side or output-side end region of the individual collector shell 1 with respect to an arrangement in an illumination system That is, the starting point is the point that is closest to the light source when the collector is used in an illumination system in the light path, and the end point is the point farthest from the light source.
• the distance between the optical axis OA and the starting point a in the zx coordinate system defines the radius ra of the first end region and the distance between the optical axis OA and the end point e the radius re of the second end region 3.
• the distance between the first and second end regions in z-direction determines the length I of the collector shell 1.
• the inventively embodied collector shell 1 has a length I, which describes the distance between the starting point a and the end point e along the optical axis OA, which is preferably greater than 120 mm, preferably in one Range between 80mm and 300mm, in particular in the range between 150 mm and 200 mm.
• Diameter, i. the diameter d (2-re) at the end point e of the collector shell 1 at the second end region 3 is ⁇ 750 mm, in particular ⁇ 200 mm, particularly preferably ⁇ 150 mm, in particular ⁇ 100 mm.
• the diameter d is in the range of 80 mm to 200 mm. re denotes the radius at the end of the shell, d. H. the distance of the end point on the shell surface from the rotation axis.
• the collector shell 1 comprises a base body 4 which is designed to be rotationally symmetrical with respect to the axis OA and which may also be referred to as a rotation shell, which has an optical surface 6 on the inner circumference 5. In this case, it is the surface of the collector shell 1, which receives a bundle of rays incident from a light source and reflects in the direction of the image.
• the base body 4 on the inner circumference 6 a layer system 7, comprising at least one optically active layer in the form of a reflection layer 8.
• the reflection layer 8 is preferably made of ruthenium.
• the collector shell 1 consists at least of the reflection layer 8 as a functional layer and at least one further layer, which is also referred to as a top or bottom layer and forms the base body 4.
• the base body comprises a metal layer, for example a Ni or Cu layer, to which a thin layer has been applied.
• the layer system 7 is thus characterized in this case only by a thin layer.
• the layer thickness D8 of the reflection layer 8 is preferably up to 150 nm, preferably between 10 and 120 nm, more preferably between 15 and 100 nm, very particularly preferably between 20 and 80 nm, for example 50 nm.
• the reflection layer 8 is applied directly as a layer on the inner periphery of the base body 4.
• the main body 4 is characterized by a layer thickness D4 which is 0.2 mm to 5 mm, preferably between 0.8 mm and 2 mm.
• the collector shell 1 is designed in the illustrated case as Ellipsoidsegment. Other embodiments are shown by way of example in FIGS. 2a and 2b.
• a collector shell 1 is designed as a paraboloid segment with respect to the optical axis OA and thus the rotational symmetry axis RA.
• the basic structure otherwise corresponds to that described in Figure 1, which is why the same reference numerals are used for the same elements.
• Figure 2b illustrates an embodiment of the collector shell 1 in the form of a combination of a hyperboloid and an ellipsoid.
• the geometry of the collector shell 1 is defined by a first annular segment 9 with a first optical surface 10 and a second annular segment 11 with a second optical surface 12 described.
• the total area of 10 and 12 corresponds to the optical surface 6.
• the collector shell 1 is in each case an inner marginal ray 13, which is defined by the end point in the meridional plane of the first optical surface 10 of the first segment 9 of the collector shell 1, and an outer marginal ray 14, which passes through the starting point of the first optical surface 10 of the first segment 9 of the collector shell 1 is defined assigned.
• the inner and outer marginal ray determine the bundle of rays picked up and passed on by the shell.
• Meridional plane is understood to mean the plane containing the optical axis or axis of rotation RA.
• Figure 3 illustrates in a schematic simplified representation as in Figure 1, a further second inventive embodiment of a collector shell 1 with ruthenium as a reflection layer 8 with the dimensions according to the invention in terms of diameter and length I. Since it is a rotationally symmetrical body with respect to the z-axis, this was in the
• the optical surface 6 is formed on the inner circumference 5 of the base body 4 by a layer system 7 in the form of a multilayer system.
• This consists of two ruthenium layers, a first ruthenium layer 16 and a second ruthenium layer 17, which are connected to one another via a first adhesive layer 18 and a second adhesive layer 19 to the base body 4.
• the first ruthenium layer 16 is thereby with a smaller layer thickness D16 than the second Ruthenium layer 17 executed.
• the layer thickness D16 is 5 nm to 20 nm, preferably 8 nm to 12 nm.
• the second layer thickness D17 is 20 nm to 80 nm, preferably between 30 nm and 60 nm.
• Adhesive layers 18 and 19 are each 1 nm to 5 nm, preferably 1 nm to 3 nm.
• an intermediate layer 20 preferably made of the material of the base layer, here nickel provided.
• the production of the collector shells 1 according to the first or also second embodiment is preferably carried out by molding via a separating layer system 15.
• the molding method is described in detail in FIGS. 4a-4b for a grazing-incidence
• the impression takes place on the outer circumference 22 of the impression body 21, wherein the impression body 21 is either a direct component of the separation layer system 15 or is coated with the release layer system, and wherein the reflective layer 8 for the grazing-incidence element is applied to the release layer system 15.
• Abform stresses 21, separating layer system 15 and layer system 7 of the collector shell 1 form the so-called impression layer system 23 before the impression.
• the impression body is also referred to as a mandrel.
• the Abform stresses itself can for example consist of quartz glass, Ni-P or galvanized aluminum.
• the separation takes place according to the invention at the interface of two materials, of which a material is preferably formed of SiÜ 2 and either directly from the Abform stresses 21 or a molded on the Abform Sciences 21, not shown here layer system can be formed, wherein the layer system 24 offset in time for the actual impression can be applied to the Abform stresses 21 and remains on this after separation or else in a time sequence with the other components of the release layer system 15 or the layer system 7 for the collector shell 1 is applied.
• the separation is essentially due to a thermal shock, which leads to partially reduced voltages, which in turn cause the adhesion between the impression body and the separation layer system to be overcome.
• the separation takes place indirectly after impression taking, ie not directly between the reflective layer 8 and the layer system 7 and the Abform stresses 21 but via a release layer system 15, comprising, in addition to the SiO 2 layer, an Au layer, wherein the separation between the SiO 2 layer and the Au layer takes place and the Au layer can later be detached.
• the separating layer system 15 consists of at least two layers - an SiO 2 and an Au layer, on which the reflection layer 8 in the form of the ruthenium layer is then deposited.
• the Abform restructuring 21 consists of a possible embodiment, for example, Ni-P. Then in a first
• FIG. 4 a shows, in a schematically simplified representation, the basic structure of the arrangement for the impression of the individual layers. This includes the
• Abform stresses 21 and associated with this evaporation device 26 can lead to a change in adhesive forces and thus influence the overall molding process.
• an Au layer is deposited on the SiO 2 layer, for example vapor-deposited, and then the ruthenium layer acting as reflection layer 8 according to the invention.
• the impression body 21 with the already applied layers of the release layer system 15 and the later layer system 7 and the layer for the main body 4 of the collector shell 1 is deposited or nickel-plated by electroforming, preferably by an electrochemical process, preferably a galvanic process directly on the ruthenium layer.
• the impression layer system 23 prior to the separation therefore consists of "Abform restructuring 21 Ni-P // SiO 2 / Au / Ru / electroplated Ni.” This is followed by separation into Abform stresses 21 and a shell 25 for a grazing-incidence collector.
• the separation takes place between SiO 2 and Au. The impression thus takes place indirectly via an intermediate layer in the form of Au.
• the Au layer is then removed from the reflection layer in the subsequent method step
• the stripping process for the Au layer is dependent on the solvent used and the process parameters for detachment, ie time duration or contact time and temperature, which are for ruthenium-coated collector shells 1 in of the size mentioned, for example, 4 to 10 minutes at room temperature In addition to the removal of the Au residues, the micro roughness on the surface 6.
• FIG. 5 illustrates the dependence of the microroughness on the process parameters of temperature and immersion time on the surface using the example of a diagram. It can be seen that significant deviations can occur here. Additional spectral reflectance measurements between a wavelength of 200nm and 1000nm clearly differentiate between the presence of an Au and a Ru surface.
• FIG. 4d illustrates, with reference to a flowchart, the impression when the impression body 21 made of quartz is formed.
• the impression body 21 made of quartz can be dispensed with the SiO 2 coating, in which case the surface of the Abform stressess must be polished with a sufficiently low micro-roughness.
• Film stress values are still low enough to permit molding without layer cracking and delamination. Opposite impression mechanically more stable layers are obtained by ion-assisted coating processes.
• the following layer thickness sizes are selected for the individual layers:
• Au in the range between 100 to 300 nm, preferably 200 nm.
• Ruthenium in the range between 10 and 150 nm, preferably 10 nm to 120 nm.
• the adhesive forces between the individual layers, in particular between SiO 2 and Au, can be varied within limits by storage or aging of the molded article 21, by a plasma surface treatment in the vapor deposition system and by vapor deposition without prior venting.
• FIG. 6a illustrates the impression body coating with the separation layer system 15 and the layer system 7 of the collector shell 1.
• an impression layer system 23 is made up of layers mentioned below formed: Abform redesign Ni-P // SiO 2 / Ru / Cr / Ru / Cr / Ni / galvanic Ni.
• FIG. 6b illustrates the layer structure after the separation.
• a layer of SiO 2 is applied to the impression body comprising Ni-P.
• an interruption takes place in which the surface 22 of the impression body 21 is exposed to a treatment for a certain period of time.
• the layer system is conditioned and a reduction or optimization of the adhesive forces between the SiO 2 and Ru layer is carried out.
• the other layers are as before mentioned evaporated.
• a first Ru layer 16 is vapor-deposited without ion support in order to avoid excessive forces. A bombardment with Ar ions from the ion source would change the conditioning of the SiO 2 layer again and greatly increase the adhesive forces.
• the better connection to the second Ru layer 17 is achieved by a Cr seed layer.
• FIG. 7 illustrates a simplified schematized representation of the structure of the vapor deposition device 26.
• an evaporation device in the form of a so-called electron beam evaporator 27 and the ion source 28.
• the individual layers are applied by vapor deposition.
• This is done by known PVD methods, such as thermal evaporation, evaporation with electron beam evaporators or sputtering, in particular magnetron sputtering.
• the arrangement for sputtering is shown schematically in simplified form in FIG.
• the rotatably mounted and drivable impression body 21 is assigned a sputtering device 29.
• This comprises at least one source 30 according to FIG. 8b, preferably several sources 30.1 to 30.5 according to FIG. 8a. These are installed parallel to the surface 22 in order to ensure the most homogeneous layer thickness distribution possible in the vapor deposition.
• FIG. 8b shows the use of a source 30 which has a correspondingly shaped effective region 31 which covers the impression body 21 in the axial direction over part of its extension.
• Figure 9 illustrates an arrangement for the production of the collector shells 1 according to an alternative method, which is characterized by the molding of the base body 4 and the time offset and taking place independently coating with the layer system according to the first and second embodiments.
• the coating is carried out by sputtering the reflection layer on the inner surface 5 of the base body 4 of the collector shell 1 by means of a sputtering device 29.
• the sputtering device is designed such that the entire inner surface is sputtered simultaneously in one step.
• FIG. 10 illustrates a section of an illumination system 32.
• This comprises a light source 33, the light of which is picked up by a collector 34.
• the schematically illustrated collector 34 comprises in the illustrated embodiment a total of three mutually arranged mirror shells 1.1, 1.2 and 1.3, which receive the light from the light source 33 under grazing incidence and image in an image of the light source.
• the mirror shells 1.1, 1.2, 1.3 of the collector can be produced by the molding method according to the invention.
• the inventive coated collector shell 1 is also characterized by the roughness.
• FIG. 11a illustrates the calculated reflection 900 for Ru for a roughness of 1.4 nm and the measured reflection (so-called band reflectivity (%)) for Ru deposited on an SiO 2 substrate with a Ni intermediate layer as a function of the angle of incidence (grazing incidence angle ) to the surface tangent at a wavelength of 13nm.
• FIG. 11b illustrates the calculated reflection for Ru for a roughness of 1.4 nm and measured reflection for Ru deposited on an SiO 2 substrate with a Cr adhesion layer as a function of the angle of incidence with respect to the surface tangent at a wavelength of 13 nm. From the angles of incidence indicated in FIGS. 11a and 11b, the following are obtained from the normal angles of incidence as follows:
• the angle of incidence of the angle of incidence of 10 ° -15 ° with respect to the surface tangent results in a reflection between 60% and 75% for the substrate // Ni / Ru layer system and 75% and 80% for the substrate substrate layer system // Cr / Ru.
• the layer system SiO 2 -
• the reflectivity or reflection decreases in% the greater the roughness of the surface is. For example, with a roughness of 5 nm and an incident angle of 15 ° tangential to the surface, the reflectivity is only 60%.
• FIGS. 12 a to g, 13 a to h and 14 a to h show three methods for producing normal-incidence elements, in particular reflective normal-incidence mirrors or facets for a faceted optical element, with the aid of impression techniques.
• AbformMech 1000 which may be formed as Si ⁇ 2 -AbformMech, a metal layer, for example applied an Au layer.
• the Abform stresses 1000 may consist of quartz glass (SiO 2 ) or kanigieninstrumentem aluminum.
• the surface roughness of the impression body is adjusted or reduced to values, for example, with the aid of superpolishing, which correspond to those which a multilayer-system coated normal-incidence mirror in the EUV wavelength range requires in order to achieve a high reflectivity, for example in the range of 70% of the to provide incident radiation.
• the superpolishing of the impression body is preferably carried out such that 0.1-1 nm of HSFR is achieved at spatial frequencies between 10 nm and a few micrometers.
• the impression body 1000 is then coated with a release layer 1010, for example an Au layer, which may preferably be in the range of 50-200 nm.
• a metal layer 1020 for example a Ni layer, is galvanically deposited on the gold layer.
• the Au layer serves as a cathode.
• the deposition of the metal by electroplating in at least two steps. This makes it possible on the path of the electrodeposition to provide a base body 1030 for a normal-incidence mirror, in the mechanical components such as joint adapter 1040 or else
• Cooling components 1050 as coolant tubes are introduced.
• a first layer 1020.1 is first applied to the Au layer 1010, as shown in step 12c or 13c.
• the coolant elements 1050 for example the cooling tubes or the joint elements 1040, are placed on the electrodeposited Ni layer 1020.1. This is shown in FIGS. 12d and 13d.
• a metal for example Ni
• the first layer 1020.1 has a layer thickness of 0.2 to 0.8 mm, preferably 0.5 mm
• the second layer 1020.2 which is deposited according to FIGS. 12e and 13e, has a Thickness from 1 to 4 mm.
• the cooling element or the mechanical element is in the
• Metal layer of the body here in the Ni layer, embedded and indeed solid and material fit, whereby a particularly low heat transfer resistance can be ensured.
• Cu can also be used for electrodeposition.
• the method may also include more than two steps.
• the system consisting of the base body 1030 made of a metallic material, namely galvanized nickel, together with the separation layer 1010, which in the present case is Au, is separated from the mold body 1000 by thermal separation.
• the thermal separation is based on a temperature shock or a temperature jump towards lower temperatures. Due to the different coefficients of thermal expansion of the metal applied to the impression body 1000, a separation of metal and impression body occurs as soon as the thermally induced stresses exceed the adhesion stresses between the metal and the mandrel.
• gold Au is a very good separation system, since the gold Au remains on the separated metal layer, for example the Ni or Cu layer.
• the roughness of the Abform stresses 1000 is also transferred to the molded base 1030 by the impression technique.
• Ruthenium Ru could also act as a separation layer system.
• the individual basic bodies can then be the basis for the coating of different normal-incidence elements, for example individual facets for a faceted optical element.
• the reflectivity of an optical element coated with an exemplary Mo / Si multilayer system is approximately 70% at a useful wavelength of approximately 13 nm.
• the metal body is coated in a multilayer system 1110. After coating, the separation is then carried out in different components.
• the advantage of the method according to FIG. 13g is that the coating is in a single
• Coating space can be made.
• the same components as in FIGS. 12a-f are indicated by the same reference numerals in FIGS. 13a-f.
• FIGS. 14a to h show an alternative method with which a normal-incidence mirror can be produced as minimally as possible by means of molding techniques.
• the same components as in FIGS. 12a-f and 13a-f are marked with reference numerals increased by 1000.
• a separating layer 2000 in this case an Ru layer, is applied by means of vapor deposition technology to a shaped body 2000, as shown in FIG. 14b.
• the Ru metal layer which is used as a release layer 2010, then the complete multilayer system 2110 consisting of Mo / Si multilayers or Mo / Be multiple layers is deposited.
• a metal for example Ni
• a metal layer deposited on the multilayer system for example an Au layer or an Ni layer, can also act as a cathode. Steps 14d to 14f correspond to steps 12d to 12f and 13d to 13f, respectively.
• the complete normal-incidence optical element with multilayer system 2110 and Ru cover layer is separated from the impression body 2000.
• the normal-incidence element for.
• a facet of a faceted optical element can be separated into different individual elements, for example with a laser.
• a normal-incidence-optical element for example a mirror
• the base body is formed from a metal.
• the optical element according to the invention is characterized in that cooling lines can be introduced in a simple manner into the main body, which serves as a carrier for the reflective layers of the mirror system.
• these cooling lines are integrally incorporated in the base body and not, as in the case of the grazing-incidence element as described in WO 02/065482, additionally applied.
• WO 02/065482 separate cooling plates, which may be traversed by cooling lines, connected to the mirror shell of a collector.
• the cooling line is introduced directly into the main body and forms an integral part of it.
• the invention thus provides a method with which it is possible to produce optical elements for microlithography applications by means of molding techniques. Furthermore, optical
• FIG. 6a in US Pat. No. 6,658,084 shows a faceted optical element, a so-called field facet mirror or a field raster element plate with a multiplicity of individual field facets or field raster elements.
• the individual field facets or field raster elements of the field facet mirror shown in US Pat. No. 6,658,084 can be produced as normal-incidence optical elements according to the method described in this application.
• each individual field facet or each individual field raster element of the field raster element plate can be provided with cooling channels or mechanical elements such as joints, for example actuators.
• the individual pupil facets or pupil raster elements of the pupil grid plate shown in FIGS. 6b1 to 6b2 in US Pat. No. 6,658,084 could also be produced as normal-incidence optical elements in accordance with the method according to the invention and thus provided with cooling channels or mechanical elements.
• Microlithography projection exposure apparatus as shown for example in Figure 10 of US 6,658,084 or Figure 12 of WO2005 / 015314, produce according to the inventive method.

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