Abstract: An optical assembly is mounted in a projection exposure apparatus (101) for EUV microlithography and includes at least one vacuum chamber (70, 71, 68a), at least one optical element (6, 7; 65, 66; 63) arranged in the vacuum chamber (70, 71, 68a), the optical element (6, 7; 65, 66; 63) having an optical surface (18) arranged to be impinged upon by a useful beam bundle (3) of the projection exposure apparatus (101), and a cleaning device (72) configured to clean the optical surface (18). The cleaning device (72) is configured to perform particle cleaning of the optical surface (18) at a gas pressure within the vacuum chamber (70,71, 68a) which is higher than a vacuum pressure (po) for performing an exposure operation with the projection exposure apparatus (101). As a result, optical elements having respective optical surfaces arranged to be impinged upon by a useful beam bundle can be cleaned reliably of foreign particles.

Abstract: An optical arrangement, in particular a projection system, illumination system or beam shaping system for EUV lithography, including at least one optical element that is arranged in a beam path of the optical arrangement and that reflects radiation in the soft X-ray- or EUV wavelength range, wherein at least during operation of the optical arrangement at least one of, preferably each of, the reflective optical elements in the beam path, at least at the optical surface, has an operating temperature of approximately 30° C. or more, preferably of approximately 100° C. or more, particularly preferably of approximately 150° C. or more, and even more preferably of approximately 250° C. or more, and wherein the optical design of the at least one reflective optical element is selected such that its optical characteristics are optimised for operation at the operating temperature. Also presented is a method for providing a reflective optical element with such an optical design.

Abstract: Components (30) in the interior of an EUV lithography device for extreme ultraviolet and soft X-ray wavelength range are cleaned by igniting a plasma, adjacent to the component (30) to be cleaned, using electrodes (29), wherein the electrodes (29) are adapted to the form of the component (30) to be cleaned. The residual gas atmosphere is measured spectroscopically on the basis of the plasma. An emission spectrum is preferably recorded in order to monitor the degree of cleaning. An optical fiber cable (31) with a coupling-in optical unit (32) is advantageously used for this purpose. Moreover, in order to monitor the contamination in the gas phase within the vacuum chambers during the operation of an EUV lithography device, it is proposed to provide modules configured to initiate a gas discharge and to detect radiation emitted on account of the gas discharge. The contamination in the gas phase can be deduced from the analysis of the measured spectrum.

Abstract: A cleaning module for an EUV lithography device with a supply (206) for molecular hydrogen, a heating filament (210) and a line (212) for atomic and/or molecular hydrogen. The line (212) has at least one bend with a bending angle of less than 120 degrees, and has a material on its inner surface which has a low recombination rate for atomic hydrogen. The supply (206) is of flared shape at its end, which faces the heating filament (210). A gentler cleaning of optical elements is achieved with such a cleaning module, or also by exciting a cleaning gas with a cold cathode or a plasma, or by filtering out charged particles via of electrical and/or magnetic fields.

Abstract: In order to clean optical components (35) inside an EUV lithography device in a gentle manner, a cleaning module for an EUV lithography device includes a supply line for molecular hydrogen and a heating filament for producing atomic hydrogen and hydrogen ions for cleaning purposes. The cleaning module also has an element, (33) arranged to apply an electric and/or magnetic field, downstream of the heating filament (29) in the direction of flow of the hydrogen (31, 32). The element can be designed as a deflection unit, as a filter unit and/or as an acceleration unit for the ion beam (32).

Abstract: A lithographic apparatus includes a projection system constructed and arranged to project a beam of radiation onto a target portion of a substrate, an internal sensor having a sensing surface, and a mini-reactor movable with respect to the sensor. The mini-reactor includes an inlet for a hydrogen containing gas, a hydrogen radical generator, and an outlet for a hydrogen radical containing gas. The mini-reactor is constructed and arranged to create a local mini-environment comprising hydrogen radicals to treat the sensing surface.

Abstract: The invention is directed to a method for at least partially removing a contamination layer (15) from an optical surface (14a) of an EUV-reflective optical element (14) by bringing a cleaning gas into contact with the contamination layer. In the method, a jet (20) of cleaning gas is directed to the contamination layer (15) for removing material from the contamination layer (15). The contamination layer (15) is monitored for generating a signal indicative of the thickness of the contamination layer (15) and the jet (20) of cleaning gas is controlled by moving the jet (20) of cleaning gas relative to the optical surface (14a) using this signal as a feedback signal. A cleaning arrangement (19 to 24) for carrying out the method is also disclosed. The invention also relates to a method for generating a jet (20) of cleaning gas and to a corresponding cleaning gas generation arrangement.

Abstract: A mirror serves for guiding a radiation bundle. The mirror has a basic body and a coating of a reflective surface of the basic body, the coating increasing the reflectivity of the mirror. A heat dissipating device serves for dissipating heat deposited in the coating. The heat dissipating device has at least one Peltier element. The coating is applied directly on the Peltier element. A temperature setting apparatus has at least one temperature sensor for a temperature of the reflective surface. A regulating device of the Temperature setting apparatus can be connected to the at least one Peltier element and is signal-connected to the at least one temperature sensor. The result is a mirror in which a heat dissipating capacity of the heat dissipating device is improved.

Abstract: An optical element includes first regions which reflect or transmit the light falling on the optical element. The optical element also includes second regions which are in each instance separated by a distance from a first region and which at least partially surround a first region. The second regions are designed to be at least in part electrically conductive and are electrically insulated from the first regions. The optical element includes a carrier element and at least two first regions in the form of mirror facets which are arranged on the carrier element. The second regions are arranged with a separation from the mirror facets on the carrier element and are electrically insulated against the carrier element as well as against the mirror facet. At least one mirror facet is surrounded by an electrically conductive second region.

Abstract: An optical system for radiation in the EUV wavelength range, in particular a projection exposure apparatus, having at least one vacuum vessel, including: at least one EUV-reflective optical element arranged in an optical path, and a holder which includes at least one sample element, the sample element having an optical surface which is exposed to incident EUV-radiation outside of the optical path, the sample element being sensitive to chemical alterations under influence of the incident EUV-radiation which also affect the optical element. The optical system further includes at least one detection unit for online detection of the contamination status of the sample element during exposure of the sample element to the incident EUV-radiation.

Abstract: An apparatus and method for measuring an outgassing in a EUV lithography apparatus. The method includes activating a surface within the EUV lithography apparatus, inducing the outgassing, analyzing a residual gas. Defining a maximum partial pressure, recording a mass spectrum of the residual gas, converting the highest-intensity peaks of the mass spectrum into sub-partial pressures, summing the sub-partial pressures, and comparing the summed result with the defined maximum partial pressure. An EUV lithography apparatus includes a residual gas analyzer and a stimulation unit comprised of at least on of an electron source, an ion source, a photon source, and a plasma source. A measurement setup for measuring the outgassing from components by analyzing the residual gas includes a residual gas analyzer, a vacuum chamber, and a stimulation unit comprised of at least on of an electron source, an ion source, a photon source, and a plasma source.

Abstract: Inside a vacuum chamber 200 a cleaning unit 204 provides atomic hydrogen or atomic deuterium for cleaning a surface 202 at a pressure of less than 10?4 Torr or of more than 10?3 Torr. The surface 202 is heated by the heating unit 203 to a temperature of at least 50° C. This allows achieving cleaning rates of more than 60 ?/h. Preferably, the surface 202 is the surface of a multilayer mirror 201 as used in an EUV lithography apparatus.

Abstract: A method to clean optical elements of an apparatus, the apparatus being configured to project a beam of radiation onto a target portion of a substrate, the apparatus comprising a plurality of optical elements arranged in sequence in the path of the radiation beam, wherein the cleaning method comprises: cleaning one or more second optical elements of the sequence, which receive one or more relatively low second radiation doses during operation of the apparatus, utilizing cumulatively shorter cleaning periods than one or more first optical elements of the sequence that receive one or more first radiation doses during operation of the apparatus, a second radiation dose being lower than each relatively high first radiation dose.

Abstract: The invention relates to an EUV lithography apparatus with at least one EUV-reflective optical surface and a cavity ringdown reflectometer adapted to determine the contamination status of the EUV-reflective optical surface for at least one contaminating substance by determining the reflectivity of the EUV-reflective optical surface for radiation at a measuring wavelength (?m). The invention further relates to a method for determining the contamination status of at least one EUV-reflective optical surface arranged in an EUV lithography apparatus for at least one contaminating substance comprising determining the reflectivity of the EUV-reflective optical surface for radiation at a measuring wavelength (?m) using a cavity ringdown reflectometer.

Abstract: Components (30) in the interior of an EUV lithography device for extreme ultraviolet and soft X-ray wavelength range are cleaned by igniting a plasma, adjacent to the component (30) to be cleaned, using electrodes (29), wherein the electrodes (29) are adapted to the form of the component (30) to be cleaned. The residual gas atmosphere is measured spectroscopically on the basis of the plasma. An emission spectrum is preferably recorded in order to monitor the degree of cleaning. An optical fiber cable (31) with a coupling-in optical unit (32) is advantageously used for this purpose. Moreover, in order to monitor the contamination in the gas phase within the vacuum chambers during the operation of an EUV lithography device, it is proposed to provide modules configured to initiate a gas discharge and to detect radiation emitted on account of the gas discharge. The contamination in the gas phase can be deduced from the analysis of the measured spectrum.

Abstract: A method and an optical arrangement for removing contamination on optical surfaces (26), which are arranged in a vacuum environment in an optical arrangement, preferably in a projection exposure apparatus (1) for EUV lithography. The method includes generating a residual gas atmosphere containing molecular hydrogen (18) and at least one inert gas (17) in the vacuum environment, generating inert gas ions (21) by ionization of the inert gas (17), preferably with EUV radiation (20), and generating atomic hydrogen (27) by acceleration of the inert gas ions (21) in the residual gas atmosphere, to remove the contamination.

Abstract: An optical arrangement, in particular a projection exposure apparatus (1) for EUV lithography, includes: a housing (2) that encloses an interior space (15); at least one, in particular reflective, optical element (4 to 10, 12, 14.1 to 14.6) that is arranged in the housing (2); at least one vacuum generating unit (3) for generating a vacuum in the interior space (15) of the housing (2); and at least one vacuum housing (18, 18.1 to 18.10) that is arranged in the interior space (15) of the housing (2) and that encloses at least the optical surface (17, 17.1, 17.2) of the optical element (4 to 10, 12, 14.1 to 14.5), wherein a contamination reduction unit is associated with the vacuum housing (18.1 to 18.10), which contamination reduction unit reduces the partial pressure of contaminating substances, in particular of water and/or hydrocarbons, at least in close proximity to the optical surface (17, 17.1, 17.2) in relation to the partial pressure of the contaminating substances in the interior space (15).

Abstract: An optical system for radiation in the EUV wavelength range, in particular a projection exposure apparatus, having at least one vacuum vessel, including: at least one EUV-reflective optical element arranged in an optical path, and a holder which includes at least one sample element, the sample element having an optical surface which is exposed to incident EUV-radiation outside of the optical path, the sample element being sensitive to chemical alterations under influence of the incident EUV-radiation which also affect the optical element. The optical system further includes at least one detection unit for online detection of the contamination status of the sample element during exposure of the sample element to the incident EUV-radiation.

Abstract: A lithographic apparatus that includes an illumination system configured to condition a radiation beam. The illumination system includes a plurality of optical components. The apparatus also includes a support constructed to support a patterning device. The patterning device is capable of imparting the radiation beam with a pattern in its cross-section to form a patterned radiation beam. The apparatus further includes a substrate table constructed to hold a substrate, and a projection system configured to project the patterned radiation beam onto a target portion of the substrate. The projection system includes a plurality of optical components. The apparatus also includes a contamination measurement unit for measuring contamination of a surface of at least one of the optical components. The contamination measurement unit is provided with a radiation sensor constructed and arranged to measure an optical characteristic of radiation received from the surface.

Abstract: An optical arrangement, in particular a projection system, illumination system or beam shaping system for EUV lithography, including at least one optical element that is arranged in a beam path of the optical arrangement and that reflects radiation in the soft X-ray- or EUV wavelength range, wherein at least during operation of the optical arrangement at least one of, preferably each of, the reflective optical elements in the beam path, at least at the optical surface, has an operating temperature of approximately 30° C. or more, preferably of approximately 100° C. or more, particularly preferably of approximately 150° C. or more, and even more preferably of approximately 250° C. or more, and wherein the optical design of the at least one reflective optical element is selected such that its optical characteristics are optimised for operation at the operating temperature. Also presented is a method for providing a reflective optical element with such an optical design.