Carl Zeiss Smt Gmbh

Walter Pauls

Norbert Wabra

Boris Bittner

Sonja Schneider

Hendrik Wagner

Ricarda Schoemer

Rumen Iliew

Renzo Capelli

Christian Wald

Christoph Petri

Florian Ahles

Toralf Gruner

Thomas Schicketanz

Matthias Manger

Dirk Hellweg

Steffen Fritzsche

Martin Weiser

Markus Koch

Matthias Roesch

Klaus Gwosch

Holger Schmidt

Steffen Bezold

Ricarda Schneider

Sebastian Vauth

Udo Kubon

Matthias Kaes

Pavel Alexeev

Grizelda Kersteen

When measuring a reflectivity of an object for measurement light, initially the object and a reflectivity measurement apparatus are provided. The latter includes a measurement light source, an object holder for holding the object and a spatially resolving detector for capturing measurement light reflected by the object. A measurement light beam impinges on a section of the object within a field of view of the measurement apparatus. The reflected measurement light coming from the impinged-upon section of the object is captured. A surface area of the captured section is at most 50 μm×50 μm. The measurement is performed by the detector. Next, at least one reflectivity parameter of the object is determined on the basis of an intensity of the captured measurement light. The result is a measurement method and a metrology system operating therewith, whereby reflectivities in particular of very finely structured objects, such as lithography masks, can be measured with sufficient precision.

Method for measuring a reflectivity of an object for measurement light and metrology system for carrying out the method

To measure an effect of a wavelength-dependent measuring light reflectivity Rof a lithography mask, a measuring light beam is caused to impinge on said lithography mask within a field of view of a measuring apparatus. The measuring light has a wavelength bandwidth between a wavelength lower limit and a wavelength upper limit differing therefrom. The reflected measuring light emanating from an impinged section of the lithography mask is captured by a detector. A filter with a wavelength-dependent transmission within the wavelength bandwidth is introduced into a beam path of the measuring light beam between the measuring light source and the detector. The measuring light reflected by the lithography mask is captured again by the detector once the filter has been introduced. The wavelength-dependent reflectivity R, or an effect of the wavelength-dependent reflectivity Ris determined on the basis of the capture results. In comparison with the prior art, this yields an improved method for measuring an effect of a measuring light reflectivity on a lithography mask. Additionally, a method for measuring an effect of a polarization of measuring light on a measuring light impingement on a lithography mask is specified, wherein as a result of this the effect of the lithography mask on measuring light is made accessible in respect of further optical parameters of a measurement.

Method for measuring an effect of a wavelength-dependent measuring light reflectivity and an effect of a polarization of measuring light on a measuring light impingement on a lithography mask

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

Method for producing a reflecting optical element of a projection exposure apparatus and reflecting optical element for a projection exposure apparatus, projection lens and projection exposure apparatus

A method for changing a shape of a surface of an optical element by particle irradiation includes: modelling the problem of determining a resulting change of the surface shape of the optical element from a control variable; determining a predefinition for the control variable of the particle irradiation from a predefined desired change of a surface shape of the optical element by ascertaining an extremum of a merit function; and radiating particles onto the surface of the optical element with a locally resolved effect distribution corresponding to the determined predefinition for the control variable, for the purpose of producing local surface changes at the surface of the optical element. Ascertaining the extremum corresponds to the solution of an Euler equation. The Euler equation defines an integral operator. The eigenvalues of the integral operator are determined, and the predefinition is a linear combination of a finite number of eigenfunctions of the integral operator.

Method for changing a surface via particle irradiation

The disclosure relates to a device for changing a shape of a surface of an optical element via electron irradiation. The device includes an electron irradiation unit for radiating electrons onto the surface with a locally resolved energy dose distribution for the purpose of producing local material densifications in the optical element. Furthermore, the device includes a control unit for determining a locally resolved energy dose distribution from a predefined desired change of a surface shape of the optical element by optimization via a minimization of a merit function, in such a way that a difference between the desired change and an actual change of the surface shape of the optical element, the actual change being brought about on account of the predefinition determined, is minimized.

Device for changing a surface shape of an optical element via electron irradiation

A film element of an EUV-transmitting wavefront correction device is arranged in a beam path and includes a first layer of first layer material having a first complex refractive index n=(1&#x2212;&#x3b4;)+i&#xdf;, with a first optical layer thickness, which varies locally over the used region in accordance with a first layer thickness profile, and a second layer of second layer material having a second complex refractive index n=(1&#x2212;&#x3b4;)+i&#xdf;, with a second optical layer thickness, which varies locally over the used region in accordance with a second layer thickness profile. The first and second layer thickness profiles differ. The deviation &#x3b4;of the real part of the first refractive index from 1 is large relative to the absorption coefficient &#xdf;of the first layer material and the deviation &#x3b4;of the real part of the second refractive index from 1 is small relative to the absorption coefficient &#xdf;of the second layer material.

Projection lens for EUV microlithography, film element and method for producing a projection lens comprising a film element

An optical assembly, in particular for a lithography system for imaging lithographic micro- or nanostructures, includes at least two optical elements arranged successively in a beam path of the optical assembly, an acquisition device designed to acquire radiation signals from marking elements on or at the at least two optical elements, and a control device coupled to the acquisition device and which is designed to determine the plurality of properties of the optically active surface of the at least two optical elements as a function of the information contained in the radiation signals originating from the marking elements. The disclosure also relates to a method for operating the optical assembly.

Optical assembly

A mirror arrangement for an EUV projection exposure apparatus for microlithography comprises a plurality of mirrors each having a layer which is reflective in the EUV spectral range and to which EUV radiation can be applied, and having a main body. In this case, at least one mirror of the plurality of mirrors has at least one layer comprising a material having a negative coefficient of thermal expansion. Moreover, a method for operating the mirror arrangement and a projection exposure apparatus are described. At least one heat source is arranged, in order to locally apply heat in a targeted manner to the at least one layer having a negative coefficient of thermal expansion of the at least one mirror.

Mirror arrangement for an EUV projection exposure apparatus, method for operating the same, and EUV projection exposure apparatus

A reflective optical element for a microlithographic projection exposure apparatus, a mask inspection apparatus or the like. The reflective optical element has an optically effective surface, an element substrate (), a reflection layer system () and at least one deformation reduction layer (). When the optically effective surface () is irradiated with electromagnetic radiation, a maximum deformation level of the reflection layer system is reduced in comparison with a deformation level of an analogously constructed reflective optical element without the deformation reduction layer.

Reflective optical element

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Huettlingen, Germany

Walter Pauls