Abstract: An objective having a plurality of optical elements arranged to image a pattern from an object field to an image field at an image-side numerical aperture NA>0.8 with electromagnetic radiation from a wavelength band around a wavelength ? includes a number N of dioptric optical elements, each dioptric optical element i made from a transparent material having a normalized optical dispersion ?ni=ni(?0)?ni(?0+1 pm) for a wavelength variation of 1 pm from a wavelength ?0. The objective satisfies the relation ? ? i = 1 N ? ? ? ? n i ? ( s i - d i ) ? ? 0 ? NA 4 ? A for any ray of an axial ray bundle originating from a field point on an optical axis in the object field, where si is a geometrical path length of a ray in an ith dioptric optical element having axial thickness di and the sum extends on all dioptric optical elements of the objective. Where A=0.2 or below, spherochromatism is sufficiently corrected.

Abstract: A method for setting an illumination geometry for an illumination optical unit for EUV projection lithography is disclosed. The method includes defining a desired illumination geometry, followed by varying tilting angles of individual mirrors of the a facet mirror within one and the same individual-mirror group. In a first tilting position, the individual mirrors are assigned via a first group-mirror illumination channel to a first facet of a second facet mirror. In at least one further tilting position, the individual mirrors are assigned either via a further illumination channel to a further facet of the second facet mirror or to a switch-off illumination channel. The tilting angle variation is carried out until an actual illumination geometry corresponds to the desired illumination geometry within predefined tolerances.

Abstract: A method of reducing image placement errors in a microlithographic projection exposure apparatus includes providing a mask, a light sensitive layer and a microlithographic projection exposure apparatus which images features of the mask onto the light sensitive surface using projection light. Subsequently, image placement errors associated with an image of the features formed on the light sensitive surface are determined either by simulation or metrologically. Then an input state of polarization of the projection light is changed to an elliptical output state of polarization which is selected such that the image placement errors are reduced.

Abstract: An imaging optical system, in particular a projection objective, for microlithography, includes optical elements to guide electromagnetic radiation with a wavelength in a path to image an object field into an image plane. The imaging optical system includes a pupil, having coordinates (p, q), which, together with the image field, having coordinates (x, y) of the optical system, spans an extended 4-dimensional pupil space, having coordinates (x, y, p, q), as a function of which a wavefront W(x, y, p, q) of the radiation passing through the optical system is defined. The wavefront W can therefore be defined in the pupil plane as a function of an extended 4-dimensional pupil space spanned by the image field (x, y) and the pupil (p, q) as W(x, y, p, q)=W(t), with t=(x, y, p, q).

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 for EUV radiation includes a mirror body, which has at least one EUV radiation-reflecting region and at least two EUV radiation-permeable regions. A spatial separation of the illumination and imaging beam paths is possible with small angles of incidence and a large object-side numerical aperture.

Abstract: A reflective optical element e.g. for use in EUV lithography, configured for an operating wavelength in the range from 5 nm to 12 nm, includes a multilayer system with respective layers of at least two alternating materials having differing real parts of the refractive index at the operating wavelength. The material having the lower real part of the refractive index is a nitride or a carbide. “Alternatively, the material having the lower real part of the refractive index is thorium, uranium or barium and the material having the higher real part of the refractive index is boron or boron carbide.

Abstract: A hexapod system is provided for aligning an optical element in semiconductor clean rooms or in a vacuum, particularly in an illumination device for a microlithographic EUV projection exposure apparatus. The system includes six hexapod supporting structures. Using a set of at least two replaceable spacer elements having a different extent in at least one direction, at least one of the six supporting structures can be adjusted. The latter is adapted so that a spacer element can be removed or a spacer element can be added while the coupling of the first coupling end to the carrying structure and the coupling of the second coupling end to the optical element are maintained. A method for aligning an optical element in semiconductor clean rooms or in a vacuum including using a hexapod system is provided.

Abstract: Substrates suitable for mirrors which are used at wavelengths in the EUV wavelength range have a main body (2) and a polishing layer (3). The polishing layer (3) has a thickness of less than 10 ?m and a root-mean-square roughness of less than 0.5 nm and the main body (2) is produced from an aluminum alloy. Moreover, a highly reflective layer (6) is provided on the polishing layer (3) of the substrate (1) of the EUV mirror (5).

Abstract: An optical system has a housing with a mount and an opening to a receiving region, the receiving region being located within the housing and including the mount. At least one optical element is inserted into and removed from the receiving region through the opening, and at least one gas supply device provides a flow of gas in the receiving region. Alternatively or in addition, the optical system has a gas lock that receives the optical element. The opening interconnects the gas lock and the receiving region of the housing, and accommodates passage of the optical element between the gas lock and the receiving region.

Abstract: An optical arrangement, e.g. a projection exposure apparatus (1) for EUV lithography, includes: a housing (2) enclosing an interior space (15); at least one, preferably reflective optical element (4-10, 12, 14.1-14.6) arranged in the housing (2); at least one vacuum generating unit (3) for the interior space (15) of the housing (2); and at least one vacuum housing (18, 18.1-18.10) arranged in the interior space (15) and enclosing at least the optical surface (17, 17.1, 17.2) of the optical element (4-10, 12, 14.1-14.5). A contamination reduction unit is associated with the vacuum housing (18.1-18.10) and 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: A method for qualifying optics (16; 14, 16) of a projection exposure tool (10) for microlithography. The optics include (16; 14, 16) at least one mirror element (14-1 to 14-7, 16-1 to 16-6) with a reflective coating (52) disposed on the latter. The method includes: irradiating electromagnetic radiation (13, 42) of at least two different wavelengths onto the optics (16; 14, 16), a penetration depth of the radiation into the coating (52) of the mirror element varying between the individual wavelengths, taking an optical measurement on the optics (16; 14, 16) for each of the wavelengths, and evaluating the measurement results for the different wavelengths taking into consideration a respective penetration depth of the radiation into the coating (52) of the mirror element for each of the different wavelengths.

Abstract: A projection lens of an EUV-lithographic projection exposure system with at least two reflective optical elements each comprising a body and a reflective surface for projecting an object field on a reticle onto an image field on a substrate if the projection lens is exposed with an exposure power of EUV light, wherein the bodies of at least two reflective optical elements comprise a material with a temperature dependent coefficient of thermal expansion which is zero at respective zero cross temperatures, and wherein the absolute value of the difference between the zero cross temperatures is more than 6K.

Abstract: The disclosure provides a positioning unit for an optical element in a microlithographic projection exposure installation having a first connecting area for connection to the optical element, and having a second connecting area for connection to an object in the vicinity of the optical element.

Abstract: A microlithographic projection exposure apparatus has a measuring device, by which a sequence of measurement values can be generated, and a processing unit for processing the measurement values. The processing unit has a processing chain which includes a plurality of digital signal processors. The first digital signal processor in the processing chain is connected to the measuring device to receive the sequence of measurement values. Each subsequent digital signal processor in the processing chain is connected to a respectively preceding digital signal processor in the processing chain. The digital signal processors are programmed so that each digital signal processor processes only a fraction of the measurement values and generates processing results therefrom, and forwards the remaining fraction of the measurement values to the respective next digital signal processor in the processing chain for processing.

Abstract: A multi facet mirror of a microlithographic projection exposure apparatus includes a plurality of mirror facet units. Each unit includes a mirror member with a body, a reflective coating provided at one end of the body and an actuating surface provided at an opposite end. The unit further includes a rest member on which the actuating surface rests while the mirror member is not moving, and an actuator that tilts the mirror member about a tilting axis. The actuator has a contact surface and a lifting member which moves the actuating surface along a lifting direction. In a first operating state of the lifting member the actuating surface rests on the rest member and in a second operating state on the contact surface. A displacement member displaces the contact surface along a lateral direction only while the lifting member is in the second operating state.

Abstract: An imaging optical system for a projection exposure system has at least one anamorphically imaging optical element. This allows a complete illumination of an image field in a first direction with a large object-side numerical aperture in this direction, without the extent of the reticle to be imaged having to be enlarged and without a reduction in the throughput of the projection exposure system occurring.

Abstract: A beam control apparatus for an illumination beam includes an imaging illumination optical unit assembly for imaging an intermediate focus of the illumination beam onto an object field to be illuminated. A control component that influences a beam path of the illumination beam is displaceable in at least one degree of freedom by at least one displacement actuator. A position sensor device of the beam control apparatus detects a position of the intermediate focus. A control device of the beam control apparatus is signal-connected to the position sensor device and the displacement actuator. From an intermediate focus position signal received from the position sensor device, the control device calculates control signals for the displacement actuator and forwards the latter to the displacement actuator for controlling the position of the intermediate focus. This results in a beam control apparatus which makes well-controllable illumination possible together with a simple construction.

Abstract: For the production of mirrors for EUV lithography, substrates are suggested having a mean relative thermal longitudinal expansion of no more than 10 ppb across a temperature difference ?T of 15° C. and a zero-crossing temperature in the range between 20° C. and 40° C. For this purpose, at least one first and one second material having low thermal expansion coefficients and opposite gradients of the relative thermal expansion as a function of temperature are selected and a substrate is produced by mixing and bonding these materials.

Abstract: A catadioptric projection objective for imaging an off-axis object field arranged in an object surface of the projection objective onto an off-axis image field arranged in an image surface of the projection objective has a front lens group, a mirror group comprising four mirrors and having an object side mirror group entry, an image side mirror group exit, and a mirror group plane aligned transversely to the optical axis and arranged geometrically between the mirror group entry and the mirror group exit; and a rear lens group.