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: 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: 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 electrical hand-held power tool includes an assembly (2) vibrating along a vibration axis (A) during operation of the power tool, at least one, transversely projecting, vibration-decoupled pivotal side handle (3), a manual switch (4) having an actuation element (5) arranged in the side handle (3) and switchingly connectable with at least one sensor switch (8) which is located in the assembly (2) in vicinity of the handle pivot point (G), by a switching rod (7) having a switching element (6) and being pivotally supported on the side handle at a switching pivot point (S) spaced from the handle pivot point (G) and from the vibration axis (A).