Carl Zeiss Smt Gmbh

Carl Zeiss Sms Ltd.

Carl Zeiss Ag

Ulrich Matejka

Holger Seitz

Thomas Frank

Johannes Ruoff

Christoph Husemann

Mario Laengle

Hans-Jürgen Mann

Thomas Scheruebl

Thomas Thaler

Sascha Perlitz

Dirk Doering

Markus Deguenther

Heiko Feldmann

Christof Baur

Sven Martin

Beat Marco Mout

Toralf Gruner

Karl-Heinz Schuster

Michael Totzeck

Susanne Beder

Lars Stoppe

Dirk Seidel

Bernd Geh

Norbert Rosenkranz

Jens Timo Neumann

Markus Koch

Wolfgang Harnisch

Ute Buttgereit

Joern Greif-Wuestenbecker

Axel Zibold

Thomas Scherübl

Rigo Richter

Joerg Frederik Blumrich

Asad Rasool

Shao-Chi Wei

Robert Birkner

Thomas Rademacher

Ralf Müller

Dominik Grau

Beate BÖHME

Sandro FÖRSTER

Herbert Gross

The invention relates to an apparatus and a method for characterizing a microlithographic mask. According to one aspect, an apparatus according to the invention comprises at least one light source which emits coherent light, an illumination optical unit which produces a diffraction-limited light spot on the mask from the coherent light of the at least one light source, a scanning device, by use of which it is possible to implement a scanning movement of the diffraction-limited light spot relative to the mask, a sensor unit, and an evaluation unit for evaluating the light that is incident on the sensor unit and has come from the mask, an output coupling element for coupling out a portion of the coherent light emitted by the at least one light source, and an intensity sensor for capturing the intensity of this output coupled portion.

Apparatus and method for characterizing a microlithographic mask

When detecting an object structure, at least one portion of the object is initially illuminated with illumination light of an at least partly coherent light source from at least one preferred illumination direction. At least one diffraction image of the illuminated portion is recorded by spatially resolved detection of the diffraction intensity of the illumination light, diffracted by the illuminated portion, in a detection plane. At least one portion of the object structure is reconstructed from the at least one recorded diffraction image using an iterative method. Here, the iteration diffraction image of a raw object structure is calculated starting from an iteration start value and said raw object structure is compared to the recorded diffraction image in each iteration step. The iteration start value is taken by starting from a raw object structure of the object structure to be detected, which is obtained by an iteration start value ascertainment method that is independent of the remaining detection method. This yields a method in which a detection of an object structure is designed to be insensitive at a given accuracy.

Method for detecting an object structure and apparatus for carrying out the method

The present application relates to an apparatus for a scanning probe microscope, said apparatus having: (a) at least one first measuring probe having at least one first cantilever, the free end of which has a first measuring tip; (b) at least one first reflective area arranged in the region of the free end of the at least one first cantilever and embodied to reflect at least two light beams in different directions; and (c) at least two first interferometers embodied to use the at least two light beams reflected by the at least one first reflective area to determine the position of the first measuring tip.

Apparatus and method for a scanning probe microscope

The invention relates to a method and an apparatus for characterizing a microlithographic mask. In a method according to the invention, structures of a mask intended for use in a lithography process in a microlithographic projection exposure apparatus are illuminated by an illumination optical unit, wherein the mask is imaged onto a detector unit which has a plurality of pixels by an imaging optical unit. Here, a plurality of individual imaging processes are carried out with a pixel resolution specified by the detector unit, wherein these individual imaging processes differ from one another in respect of the position of at least one polarization-optical element situated in the imaging optical unit, wherein image data recorded by the detector unit are evaluated in an evaluation unit, wherein polarization-dependent effects on account of a polarization dependence of the interference of electromagnetic radiation that takes place in the wafer plane during the operation of the microlithographic projection exposure apparatus are emulated, wherein a conversion of the image data obtained in the individual imaging processes is implemented, in each case on the basis of at least one calibration image obtained by imaging a structure-free region of the mask onto the detector unit, wherein the calibration image respectively used is chosen differently depending on the position of the at least one polarization-optical element.

Method and apparatus for characterizing a microlithographic mask

The invention relates to a device and a method for characterizing a microlithographic mask. A device according to the invention has an illumination optical unit for illuminating structures of a mask intended for use in a lithography process in a microlithographic projection exposure apparatus, a detector unit, and an evaluation unit for evaluating the data recorded by the detector unit, wherein the detector unit is configured for the spatially resolved determination of both the intensity and the polarization state of the respectively impinging light emanating from the mask.

Device and method for characterizing a microlithographic mask

In detecting the structure of a lithography mask, a portion of the lithography mask is firstly illuminated with illumination light of an at least partially coherent light source in the at least one preferred illumination direction. A diffraction image of the illuminated portion is then recorded by spatially resolved detection of a diffraction intensity of the illumination light diffracted from the illuminated portion in a detection plane. The steps of 'illuminating' and 'recording the diffraction image' are then carried out for further portions of the lithography mask. Between at least two portions of the lithography mask that are thereby detected, there is in each case an overlap region whose surface extent measures at least 5% or more of the smaller of the two portions of the lithography mask. The repetition takes place until the detected portions of the lithography mask completely cover a region of the lithography mask to be detected. The structure of the lithography mask is calculated from the recorded diffraction images of the illuminated portions. A device for carrying out the structure detection method is also specified, which comprises a light source, a spatially-resolving detector and a mask holder. This results in a method and a device for detecting the structure of a lithography mask, in which the demands placed on an optical unit arranged downstream in the beam path from the illumination light of the lithography mask are reduced.

Method for detecting a structure of a lithography mask and device for carrying out the method

A detection device serves for detecting a structure on an area portion of a lithography mask. The detection device has a first spatially resolving detector and also a further spatially resolving detector arranged separately therefrom. The first spatially resolving detector is embodied as a high-intensity (HI) detector and is arranged in an HI beam path of the detection light which emanates from the mask area portion. The further spatially resolving detector is embodied as a low-intensity (LI) detector and is arranged in an LI beam path of the detection light. The HI beam path on the one hand and the LI beam path on the other hand are embodied such that the HI detector is illuminated with a detection light intensity that is at least twice the magnitude of the detection light intensity with which the LI detector is illuminated. The two spatially resolving detectors are embodied for simultaneously detecting the detection light. The result is a detection device whose dynamic range is increased without limitations of a spatial resolution. Alternatively or additionally, the detection device, by way of the two spatially resolving detectors, can also be embodied for the polarization-resolved measurement of the detection light.

Detection device for detecting a structure on an area portion of a lithography mask, and apparatus comprising a detection device of this type

The invention relates to a method and a device for characterizing a mask for microlithography. In a method according to the invention, structures of a mask intended for use in a lithography process in a microlithographic projection exposure apparatus are illuminated by an illumination optical unit, wherein the mask is imaged onto a detector unit by an imaging optical unit, wherein image data recorded by the detector unit are evaluated in an evaluation unit. In this case, for emulating an illumination setting predefined for the lithography process in the microlithographic projection exposure apparatus, the imaging of the mask onto the detector unit is carried out in a plurality of individual imagings which differ from one another with regard to the illumination setting set in the illumination optical unit or the polarization-influencing effect set in the imaging optical unit.

Method and device for characterizing a mask for microlithography

In a method for three-dimensionally measuring a 3D aerial image in the region around an image plane during the imaging of a lithography mask, which is arranged in an object plane, a selectable imaging scale ratio in mutually perpendicular directions (x, y) is taken into account. For this purpose, an electromagnetic wavefront of imaging light is reconstructed after interaction thereof with the lithography mask. An influencing variable that corresponds to the imaging scale ratio is included. Finally, the 3D aerial image measured with the inclusion of the influencing variable is output. This results in a measuring method with which lithography masks that are optimized for being used with an anamorphic projection optical unit during projection exposure can also be measured.

Method for three-dimensionally measuring a 3D aerial image of a lithography mask

An imaging optical unit serves within a metrology system for examining a lithography mask. The lithography mask can be arranged in an object field of the imaging optical unit. The object field is defined by two mutually perpendicular object field coordinates. The imaging optical unit has an aperture stop of which the aspect ratio in the direction of the two object field coordinates differs from 1. This results in an imaging optical unit which can be used for the examination of lithography masks that are designed for projection exposure with an anamorphic projection optical unit.

Imaging optical unit for a metrology system for examining a lithography mask

An illumination optical unit serves for illuminating objects to be examined by a metrology system. The illumination optical unit has an optical pupil shaping assembly for generating a defined distribution of illumination angles of illumination light over an object field in which an object to be examined can be arranged. An optical field shaping assembly for generating a defined intensity distribution of the illumination light over the object field is disposed downstream of the pupil shaping assembly in the beam path of the illumination light. The field shaping assembly has at least one optical field shaping element arranged in the region of a pupil plane of the illumination optical unit. This results in an illumination optical unit which ensures an illumination which can be set in a defined manner with regard to an intensity distribution and an illumination angle distribution over the entire object field.

Illumination optical unit for a metrology system and metrology system comprising such an illumination optical unit

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Jena, Germany

Ulrich Matejka