A method localizes assembly errors during the arrangement and/or the assembly of in particular vibration-isolated structural elements, in particular of components of optical arrangements, preferably of microlithographic projection exposure apparatuses.

Embodiments described herein relate to a dynamically controlled lens used in lithography tools. Multiple regions of the dynamic lens can be used to transmit a radiation beam for lithography process. By allowing multiple regions to transmit the radiation beam, the dynamically controlled lens can have an extended life cycle compared to conventional fixed lens. The dynamically controlled lens can be replaced or exchanged at a lower frequency, thus, improving efficiency of the lithography tools and reducing production cost.

A filter assembly, for example for a control loop for controlling the position of at least one element, comprises first and second filters. The first filter suppresses an undesired component in a signal to be filtered. The first filter produces a first signal delay in a first frequency range. The second filter produces a second signal delay in the first frequency range. The second signal delay at least partly compensates the first signal delay.

The present invention provides a fluid purging system (100) for an optical element (120), comprising a fluid guiding unit arranged to guide a fluid, provided by a fluid supply system, over at least a curved portion of an optical surface (122) of the optical element. The fluid guiding unit comprises a fluid inlet and a first nozzle unit (110) for providing a fluid to the optical surface. The fluid guiding unit being formed by at least a first wall portion (102) and at least a second wall portion (104), wherein the second wall portion being configured to face the optical surface and to follow a contour of the optical surface. The second wall portion comprises a second nozzle unit (112).

The present invention provides an exposure apparatus that exposes a substrate, comprising: an optical system configured to emit, in a first direction, light for exposing the substrate; a first supplier configured to supply a gas into a chamber where the optical system is arranged; and a second supplier configured to supply a gas to an optical path space where the light from the optical system passes through, wherein the second supplier includes a gas blower including a blowing port from which a gas is blown out in a second direction, and the guide member configured to guide the gas blown out from the blowing port to the optical path space, and the guide member includes a plate member extended on a side of the first direction of the blowing port so as to be arranged along the second direction.

Degradation of the reflectivity of one or more reflective optical elements in a system for generating EUV radiation is reduced by the controlled introduction of a gas into a vacuum chamber containing the optical element. The gas may be added to the flow of another gas such as hydrogen or alternated with the introduction of hydrogen radicals.

The invention relates to a device for measuring a substrate for semiconductor lithography with a reference interferometer for ascertaining the change in the ambient conditions, wherein the reference interferometer comprises a means for changing the optical path length of a measurement section of the reference interferometer, wherein the means is configured to bring about a change in the refractive index.

Furthermore, the invention relates to a method for correcting cyclic error components of a reference interferometer, wherein the reference interferometer comprises a means for changing the optical path length of a measurement section of the reference interferometer, comprising the following method steps: starting up the reference interferometer, continuously detecting measurement values of the reference interferometer, changing the optical path length of the measurement section of the reference interferometer until a path length change of at least one quarter of the wavelength of the reference interferometer is detected, determining the cyclic errors on the basis of the continuously detected measurement values of the reference interferometer, and correcting the current measurement values ascertained by the reference interferometer on the basis of the cyclic errors ascertained.

A method for producing a reflecting optical element for a projection exposure apparatus (1). The element has a substrate (30) with a substrate surface (31), a protection layer (38) and a layer partial system (39) suitable for the EUV wavelength range. The method includes: (a) measuring the substrate surface (31), (b) irradiating the substrate (30) with electrons (36), and (c) tempering the substrate (30). Furthermore, an associated reflective optical element for the EUV wavelength range, a projection lens with a mirror (18, 19, 20) as reflective optical element, and a projection exposure apparatus (1) including such a projection lens.

An extreme ultraviolet light concentrating mirror may include a substrate, a multilayer reflection film provided on the substrate and configured to reflect extreme ultraviolet light, and a protective film provided on the multilayer reflection film. Here, the protective film may include a mixed film in which a network-forming oxide is mixed with an amorphous titanium oxide, or a mixed film in which two or more amorphous titanium oxide layers and two or more network-forming oxide layers are each alternately laminated.

A vacuum system includes a wall of a vacuum chamber, a flange of the vacuum chamber, an outer seal disposed between the wall and the flange, and an inner seal disposed between the wall and the flange. The outer seal includes a first material; the inner seal includes a second material distinct from the first material. The inner seal is closer to the interior of the vacuum chamber than the outer seal and is separated from the outer seal by a gap. The outer seal may be capable of providing tighter vacuum sealing between the wall and the flange than the inner seal. The inner seal may be more resistant than the outer seal to a gas to be used to clean the interior of the vacuum chamber. The vacuum system also includes a path to couple the gap to a first vacuum pump, to evacuate the gap.