Abstract: A method for forming in particular reflection-reducing nanostructures (5) on a preferably polished surface (3) of a crystalline, in particular ionic, substrate (1) for transmission of radiation in the FUV/VUV wavelength range. The method includes: providing a surface (3, 7), which surface is not oriented along a lattice plane having a minimum surface energy, on the substrate (1) or on a layer (6) applied to the substrate (1) by a coating method, in particular vacuum vapor deposition, and introducing an energy input (E) into the surface (7) for rearranging the surface (7) to form the nanostructures (5), wherein the energy input (E) is generated by irradiating the surface (7) with electromagnetic radiation (4). Also, an optical element for transmission of radiation in the FUV/VUV wavelength range.

Abstract: A method of forming a layer (3) on a substrate (2) made of a fluoridic material includes: depositing a coating material (9) on the substrate to form the layer and generating a plasma (12) to assist the deposition of the coating material. The plasma is formed from a gas mixture (14) containing a first gas (G) and a second gas (H), wherein the second gas has an ionization energy less than an ionization energy of the first gas, the first gas is a noble gas and the second gas is a further noble gas. An associated optical element includes: a substrate (2) composed of a fluoridic material, in particular a metal fluoride, wherein the substrate has a coating (18) having a layer (3) formed by the above method. An associated optical system, in particular for the DUV wavelength range, includes at least one such optical element.

Abstract: A reflective optical element (17), in particular for reflecting EUV radiation (16), includes: a substrate (25), and a reflective coating (26) applied to the substrate (25). In one disclosed aspect, the substrate (25) is doped within its volume (V) with at least one precious metal (27). In a further disclosed aspect, the reflective coating (26) and/or a structured layer (28) that is formed between the substrate (25) and the reflective coating (26) is doped with at least one precious metal (27). Also disclosed are an optical arrangement, preferably a projection exposure apparatus for microlithography, in particular for EUV lithography, which includes at least one such reflective optical element (17), and a method of producing such a reflective optical element (17).

Abstract: A method for producing an optical element (2), in particular for a projection exposure system (400), according to which a protective layer (11) consisting of a protective material is applied to a surface of a main body (7) until a protective layer thickness is obtained. The main body (7) has a substrate (17) and a reflective layer (18) applied to the substrate (17). The protective layer (11) is at least substantially defect-free.

Abstract: Provided for herein are methods for producing reflective optical elements for the EUV wavelength range which have grating structures or which include structures that can serve as phase shifters. The methods may include the following operations: applying a structurable layer to a substrate, applying a reflective coating to the substrate that has been provided with the structurable layer, and locally irradiating the structurable layer. The structurable layer may be irradiated before or after application of the reflective coating.

Abstract: In situ dynamic protection of an optical element surface against degradation includes disposing the optical element in an interior of an optical assembly for the FUV/VUV wavelength range and supplying at least one volatile fluorine-containing compound (A, B) to the interior for dynamic deposition of a fluorine-containing protective layer on the surface. The protective layer (7) is deposited on the surface layer by layer via a molecular layer deposition process. The compound includes a fluorine-containing reactant (A) supplied to the interior in a pulsed manner. A further reactant (B) is supplied to the interior also in a pulsed manner. An associated optical assembly includes an interior in which a surface is disposed, and at least one metering apparatus (123) that supplies a reactant to the interior. The metering apparatus provides a pulsed supply of the compound as a reactant (A, B) for layer by layer molecular layer deposition.

Abstract: A mirror, e.g. for a microlithographic projection exposure apparatus, includes an optical effective surface, a mirror substrate, a reflection layer stack for reflecting electromagnetic radiation incident on the optical effective surface, at least one first electrode arrangement, at least one second electrode arrangement, and an actuator layer system situated between the first and the second electrode arrangements. The actuator layer system is arranged between the mirror substrate and the reflection layer stack, has a piezoelectric layer, and reacts to an electrical voltage applied between the first and the second electrode arrangements with a deformation response in a direction perpendicular to the optical effective surface. The deformation response varies locally by at least 20% in PV value for a predefined electrical voltage that is spatially constant across the piezoelectric layer.

Abstract: A method for in situ protection of a surface (7a) of an aluminum layer (7) of a VUV radiation reflecting coating (6) of an optical element (4), arranged in an interior of an optical arrangement, against the growth of an aluminum oxide layer (8), including carrying out an atomic layer etching process for layer-by-layer removal of the aluminum oxide layer from the surface. The etching process includes a surface modification step and a material detachment step. At least one boron halide is supplied as a surface modifying reactant to the interior in pulsed fashion during the surface modification step. A plasma is generated at a surface (8a) of the aluminum oxide layer, at least during the material detachment step. The atomic layer etching process is performed until the aluminum oxide layer reaches a given thickness (D), or the aluminum oxide layer is kept below that thickness (D) by the process.

Abstract: A mirror that has a mirror substrate (12), a reflection layer stack (21) reflecting electromagnetic radiation incident on the optical effective surface (11), and at least one piezoelectric layer (16) arranged between the mirror substrate and the reflection layer stack and to which an electric field for producing a locally variable deformation is applied by way of a first electrode arrangement and a second electrode arrangement situated on alternate sides of the piezoelectric layer. In one aspect, both the first and the second electrode arrangements have a plurality of electrodes (20a, 20b), to each of which an electrical voltage relative to the respective other electrode arrangement can be applied via leads (19a, 19b). Separate mediator layers (17a, 17b) set continuous electrical potential profiles along the respective electrode arrangement, and where said mediator layers differ from one another in their average electrical resistance by a factor of at least 1.5.

Abstract: Treating a reflective optical element (104) for the EUV wavelength range that has a reflective coating on a substrate. The reflective optical element in a holder (106) is irradiated with at least one radiation pulse of a radiation source (102) having a duration of between 1 ?s and 1 s. At least one radiation source (102) and the reflective optical element move relative to one another. Preferably, this is carried out directly after applying the reflective coating in a coating chamber (100). Reflective optical elements of this type are suitable in particular for use in EUV lithography or in EUV inspection of masks or wafers, for example.

Abstract: In situ dynamic protection of an optical element surface against degradation includes disposing the optical element in an interior of an optical assembly for the FUV/VUV wavelength range and supplying at least one volatile fluorine-containing compound (A, B) to the interior for dynamic deposition of a fluorine-containing protective layer on the surface. The protective layer (7) is deposited on the surface layer by layer via a molecular layer deposition process. The compound includes a fluorine-containing reactant (A) supplied to the interior in a pulsed manner. A further reactant (B) is supplied to the interior also in a pulsed manner. An associated optical assembly includes an interior in which a surface is disposed, and at least one metering apparatus (123) that supplies a reactant to the interior. The metering apparatus provides a pulsed supply of the compound as a reactant (A, B) for layer by layer molecular layer deposition.

Abstract: A method for forming in particular reflection-reducing nanostructures (5) on a preferably polished surface (3) of a crystalline, in particular ionic, substrate (1) for transmission of radiation in the FUV/VUV wavelength range. The method includes: providing a surface (3, 7), which surface is not oriented along a lattice plane having a minimum surface energy, on the substrate (1) or on a layer (6) applied to the substrate (1) by a coating method, in particular vacuum vapor deposition, and introducing an energy input (E) into the surface (7) for rearranging the surface (7) to form the nanostructures (5), wherein the energy input (E) is generated by irradiating the surface (7) with electromagnetic radiation (4). Also, an optical element for transmission of radiation in the FUV/VUV wavelength range.

Abstract: A method for in situ protection of a surface (7a) of an aluminum layer (7) of a VUV radiation reflecting coating (6) of an optical element (4), arranged in an interior of an optical arrangement, against the growth of an aluminum oxide layer (8), including carrying out an atomic layer etching process for layer-by-layer removal of the aluminum oxide layer from the surface. The etching process includes a surface modification step and a material detachment step. At least one boron halide is supplied as a surface modifying reactant to the interior in pulsed fashion during the surface modification step. A plasma is generated at a surface (8a) of the aluminum oxide layer, at least during the material detachment step. The atomic layer etching process is performed until the aluminum oxide layer reaches a given thickness (D), or the aluminum oxide layer is kept below that thickness (D) by the process.

Abstract: A cost-effective method for repairing reflective optical elements for EUV lithography. These optical elements (60) have a substrate (61) and a coating (62) that reflects at a working wavelength in the range between 5 nm and 20 nm and is damaged as a result of formation of hydrogen bubbles. The method includes: localizing a damaged area (63, 64, 65, 66) in the coating (62) and covering the damaged area (63, 64, 65, 66) with one or more materials having low hydrogen permeability by applying a cover element to the damaged area. The cover element is formed of a surface structure, a convex or concave surface, or a coating corresponding to the coating of the reflective optical element, or a combination thereof. The method is particularly suitable for collector mirrors (70) for EUV lithography. After the repair, the optical elements have cover elements (71, 72, 73).

Abstract: An optical element for an optical system, in particular an optical system of a microlithographic projection exposure apparatus or mask inspection apparatus, and a method for correcting the wavefront effect of an optical element. The optical element has at least one correction layer (12, 22) and a manipulator that manipulates the layer stress in this correction layer such that a wavefront aberration present in the optical system is at least partially corrected by this manipulation. The manipulator has a radiation source for spatially resolved irradiation of the correction layer with electromagnetic radiation (5). This spatially resolved irradiation enables a plurality of spaced apart regions (12a, 12b, 12c, . . . ; 22a, 22b, 22c, . . . ) to be generated, equally modified in terms of their respective structures, in the correction layer.

Abstract: A mirror that has a mirror substrate (12), a reflection layer stack (21) reflecting electromagnetic radiation incident on the optical effective surface (11), and at least one piezoelectric layer (16) arranged between the mirror substrate and the reflection layer stack and to which an electric field for producing a locally variable deformation is applied by way of a first electrode arrangement and a second electrode arrangement situated on alternate sides of the piezoelectric layer. In one aspect, both the first and the second electrode arrangements have a plurality of electrodes (20a, 20b), to each of which an electrical voltage relative to the respective other electrode arrangement can be applied via leads (19a, 19b). Separate mediator layers (17a, 17b) set continuous electrical potential profiles along the respective electrode arrangement, and where said mediator layers differ from one another in their average electrical resistance by a factor of at least 1.5.

Abstract: An optical element for an optical system, in particular an optical system of a microlithographic projection exposure apparatus or mask inspection apparatus, and a method for correcting the wavefront effect of an optical element. The optical element has at least one correction layer (12, 22) and a manipulator that manipulates the layer stress in this correction layer such that a wavefront aberration present in the optical system is at least partially corrected by this manipulation. The manipulator has a radiation source for spatially resolved irradiation of the correction layer with electromagnetic radiation (5). This spatially resolved irradiation enables a plurality of spaced apart regions (12a, 12b, 12c, . . . ; 22a, 22b, 22c, . . . ) to be generated, equally modified in terms of their respective structures, in the correction layer.

Abstract: In order to prevent delamination of a reflective coating from the substrate under the influence of reactive hydrogen, a reflective optical element (50) for EUV lithography is provided, which has a substrate (51) and a reflective coating (54) for reflecting radiation in the wavelength range of 5 nm to 20 nm. A functional layer (60) is arranged between the reflective coating (54) and the substrate (51). With the functional layer, the concentration of hydrogen in atom % at the side of the substrate facing the reflective coating is reduced by at least a factor of 2.

Abstract: In order to make possible both good laser resistance and good antireflection properties, an optical element, in particular for UV lithography, comprising a substrate and a coating on the substrate having at least four layers, is proposed, wherein a first layer comprising a low refractive index inorganic fluoride compound is arranged on the substrate, a layer comprising an inorganic oxide-containing compound is arranged as a layer the most distant from the substrate, and at least two further layers each comprising an inorganic fluoride compound or an inorganic oxide-containing compound are arranged alternately between the first and the most distant layers.

Abstract: An optical grating (8) includes a substrate (9), on the surface (9a) of which a periodic structure (10) is formed that is embodied to diffract incident radiation (11), in particular incident EUV radiation, with a specified wavelength (??) into a predetermined order of diffraction, in particular into the first order of diffraction (m=+1). The optical grating also has a coating (12) applied onto the periodic structure with at least one layer (13, 14) that is embodied to suppress the diffraction of the incident radiation into at least one higher order of diffraction (m=+2, . . . ) than the predetermined order of diffraction.