Patents by Inventor Daniel Kraehmer

Daniel Kraehmer has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20080043331
    Abstract: Projection objectives of micro-lithographic projection exposure apparatuses, as well as related methods and components, are disclosed.
    Type: Application
    Filed: August 15, 2007
    Publication date: February 21, 2008
    Applicant: CARL ZEISS SMT AG
    Inventors: Daniel Kraehmer, Johannes Ruoff
  • Patent number: 7317508
    Abstract: An optical system of a microlithographic exposure apparatus comprises at least one optical element (L1 to L16, 15, 16, 24) having a locally varying birefringence direction distribution that is caused by stress-induced birefringence and is at least substantially rotationally symmetrical. At least one birefringent correcting element (K1, K2; K?) is made of a crystal having a location independent birefringence direction distribution that is at least substantially rotationally symmetrical. The crystal has a crystal lattice orientation that is oriented such that its birefringence direction distribution is at least substantially perpendicular to the locally varying birefringence direction distribution of the at least one optical element (L1 to L16, 15, 16, 24).
    Type: Grant
    Filed: November 24, 2004
    Date of Patent: January 8, 2008
    Assignee: Carl Zeiss SMT AG
    Inventors: Daniel Kraehmer, Wilhelm Ulrich
  • Publication number: 20080002167
    Abstract: The invention concerns a method for operating a projection exposure apparatus to project the image of a structure of an object (5) arranged in an object plane (6) onto a substrate (10) arranged in an image plane (8). The object (5) is illuminated with light of an operating wavelength of the projection exposure apparatus according to one of several adjustable exposure modes. The light produces changes in at least one optical element (9) of the projection exposure apparatus, by which the optical properties of the projection exposure apparatus are influenced. The operation of the projection exposure apparatus makes allowance for the influencing of the optical properties of the projection exposure apparatus or a quantity dependent on the former, being calculated approximately on the basis of the exposure mode used and the structure of the object (5).
    Type: Application
    Filed: June 28, 2006
    Publication date: January 3, 2008
    Applicant: Carl Zeiss SMT AG
    Inventors: Toralf Gruner, Olaf Conradi, Nils Dieckmann, Markus Schwab, Olaf Hmann, Michael Totzeck, Daniel Kraehmer, Vladimir Kamenov
  • Publication number: 20070242250
    Abstract: Objective, in particular a projection objective for a microlithography projection-exposure installation, with at least one fluoride crystal lens. A reduction in the detrimental influence of birefringence is achieved if this lens is a (100)-lens with a lens axis which is approximately perpendicular to the {100} crystallographic planes or to the crystallographic planes equivalent thereto of the fluoride crystal. In the case of objectives with at least two fluoride crystal lenses, it is favorable if the fluoride crystal lenses are arranged such that they are rotated with respect to one another. The lens axes of the fluoride crystal lenses may in this case point not only in the <100> crystallographic direction but also in the <111> crystallographic direction or in the <110> crystallographic direction.
    Type: Application
    Filed: June 19, 2007
    Publication date: October 18, 2007
    Applicant: CARL ZEISS SMT AG
    Inventors: Aksel Goehnermeier, Alexandra Pazidis, Birgit Kuerz, Christoph Zaczek, Daniel Kraehmer
  • Publication number: 20070211246
    Abstract: The disclosure relates to a method of manufacturing a polarization-modulating optical element, wherein the element causes, for light passing through the element and due to stress-induced birefringence, a distribution of retardation between orthogonal states of polarization, the method comprising joining a first component and a second component, wherein a non-plane surface of the first component being provided with a defined height profile is joined with a plane surface of the second component, whereby a mechanical stress causing the stress-induced birefringence is produced in the such formed polarization-modulating optical element.
    Type: Application
    Filed: April 24, 2007
    Publication date: September 13, 2007
    Applicant: CARL ZEISS SMT AG
    Inventors: Daniel Kraehmer, Ralf Mueller
  • Publication number: 20070195423
    Abstract: A method of determining materials of lenses contained in an optical system of a projection exposure apparatus is described. First, for each lens of a plurality of the lenses, a susceptibility factor KLT/LH is determined. This factor is a measure of the susceptibility of the respective lens to deteriorations caused by at least one of lifetime effects and lens heating effects. Then a birefringent fluoride crystal is selected as a material for each lens for which the susceptibility factor KLT/LH is above a predetermined threshold. Theses lenses are assigned to a first set of lenses. For these lenses, measures are determined for reducing adverse effects caused by birefringence inherent to the fluoride crystals.
    Type: Application
    Filed: January 25, 2007
    Publication date: August 23, 2007
    Inventors: Vladimir Kamenov, Daniel Kraehmer, Michael Totzeck, Toralf Gruner, Aurelian Dodoc, David Shafer, Wilhelm Ulrich, Rudolf Buenau, Hans-Juergen Mann, Alexander Epple
  • Patent number: 7239447
    Abstract: An objective, in particular a projection objective for a microlithography projection-exposure installation, with at least one fluoride crystal lens is disclosed. A reduction in the detrimental influence of birefringence is achieved if this lens is a (100)-lens with a lens axis which is approximately perpendicular to the {100} crystallographic planes or to the crystallographic planes equivalent thereto of the fluoride crystal. A further reduction in the detrimental influence of birefringence is obtained by covering an optical element with a compensation coating.
    Type: Grant
    Filed: September 1, 2004
    Date of Patent: July 3, 2007
    Assignee: Carl Zeiss SMT AG
    Inventors: Aksel Goehnermeier, Alexandra Pazidis, Birgit Kuerz, Christoph Zaczek, Daniel Kraehmer
  • Patent number: 7239450
    Abstract: A method of determining materials of lenses contained in an optical system of a projection exposure apparatus is described. First, for each lens of a plurality of the lenses, a susceptibility factor KLT/LH is determined. This factor is a measure of the susceptibility of the respective lens to deteriorations caused by at least one of lifetime effects and lens heating effects. Then a birefringent fluoride crystal is selected as a material for each lens for which the susceptibility factor KLT/LH is above a predetermined threshold. Theses lenses are assigned to a first set of lenses. For these lenses, measures are determined for reducing adverse effects caused by birefringence inherent to the fluoride crystals.
    Type: Grant
    Filed: July 14, 2005
    Date of Patent: July 3, 2007
    Assignee: Carl Zeiss SMT AG
    Inventors: Vladimir Kamenov, Daniel Kraehmer, Michael Totzeck, Toralf Gruner, Aurelian Dodoc
  • Patent number: 7180667
    Abstract: An objective for a microlithography projection system has at least one fluoride crystal lens. The effects of birefringence, which are detrimental to the image quality, are reduced if the lens axis of the crystal lens is oriented substantially perpendicular to the {100}-planes or {100}-equivalent crystallographic planes of the fluoride crystal. If two or more fluoride crystal lenses are used, they should have lens axes oriented in the (100)-, (111)-, or (110)-direction of the crystallographic structure, and they should be oriented at rotated positions relative to each other. The birefringence-related effects are further reduced by using groups of mutually rotated (100)-lenses in combination with groups of mutually rotated (111)- or (110)-lenses. A further improvement is also achieved by applying a compensation coating to at least one optical element of the objective.
    Type: Grant
    Filed: April 1, 2004
    Date of Patent: February 20, 2007
    Assignee: Carl Zeiss SMT AG
    Inventors: Daniel Krähmer, Toralf Gruner, Wilhelm Ulrich, Birgit Enkisch, Michael Gerhard, Martin Brunotte, Christian Wagner, Winfried Kaiser, Manfred Maul, Christof Zaczek
  • Publication number: 20070007491
    Abstract: The invention concerns an optical element, in particular for an objective or an illumination system of a microlithographic projection exposure apparatus, including a substrate which for light of a predetermined working wavelength which passes through the substrate causes a first retardation between mutually perpendicular polarization states, and a layer which is epitaxially grown on the substrate and which is made from a material with non-cubic crystal structure, which by virtue of natural birefringence causes a second retardation between mutually perpendicular polarization states, which at least partially compensates for the first retardation caused in the substrate.
    Type: Application
    Filed: April 28, 2006
    Publication date: January 11, 2007
    Inventors: Ralf Mueller, Olaf Dittmann, Michael Totzeck, Daniel Kraehmer, Christoph Zaczek, Karl-Heinz Schuster
  • Patent number: 7145720
    Abstract: An objective for a microlithography projection system has at least one fluoride crystal lens. The effects of birefringence, which are detrimental to the image quality, are reduced if the lens axis of the crystal lens is oriented substantially perpendicular to the {100}-planes or {100}-equivalent crystallographic planes of the fluoride crystal. If two or more fluoride crystal lenses are used, they should have lens axes oriented in the (100)-, (111)-, or (110)-direction of the crystallographic structure, and they should be oriented at rotated positions relative to each other. The birefringence-related effects are further reduced by using groups of mutually rotated (100)-lenses in combination with groups of mutually rotated (111)- or (110)-lenses. A further improvement is also achieved by applying a compensation coating to at least one optical element of the objective.
    Type: Grant
    Filed: February 12, 2003
    Date of Patent: December 5, 2006
    Assignee: Carl Zeiss SMT AG
    Inventors: Daniel Krähmer, Toralf Gruner, Wilhelm Ulrich, Birgit Enkisch, Michael Gerhard, Martin Brunotte, Christian Wagner, Winfried Kaiser, Manfred Maul, Christof Zaczek
  • Publication number: 20060238735
    Abstract: An optical system of a microlithographic exposure apparatus has a pupil plane, a field plane and at least one intrinsically birefringent optical element that is positioned in or in close proximity to the field plane. A force application unit exerts mechanical forces to a correction optical element, which is positioned in or in close proximity to the pupil plane. The forces cause stress that induces a birefringence in the correction optical element such that a retardance distribution in an exit pupil is at least substantially rotationally symmetrical. An optical surface may be aspherically deformed such that a wavefront error, which is as result of deformations caused by the application of forces, is at least substantially corrected.
    Type: Application
    Filed: April 10, 2006
    Publication date: October 26, 2006
    Inventors: Vladimir Kamenov, Erwin Gaber, Daniel Kraehmer, Toralf Gruner
  • Patent number: 7126765
    Abstract: An objective for a microlithography projection system has at least one fluoride crystal lens. The effects of birefringence, which are detrimental to the image quality, are reduced if the lens axis of the crystal lens is oriented substantially perpendicular to the {100}-planes or {100}-equivalent crystallographic planes of the fluoride crystal. If two or more fluoride crystal lenses are used, they should have lens axes oriented in the (100)-, (111)-, or (110)-direction of the crystallographic structure, and they should be oriented at rotated positions relative to each other. The birefringence-related effects are further reduced by using groups of mutually rotated (100)-lenses in combination with groups of mutually rotated (111)- or (110)-lenses. A further improvement is also achieved by applying a compensation coating to at least one optical element of the objective.
    Type: Grant
    Filed: January 5, 2005
    Date of Patent: October 24, 2006
    Assignee: Carl Zeiss SMT AG
    Inventors: Daniel Krähmer, Toralf Gruner, Wilhelm Ulrich, Birgit Enkisch, Michael Gerhard, Martin Brunotte, Christian Wagner, Winfried Kaiser, Manfred Maul, Christof Zaczek
  • Publication number: 20060109560
    Abstract: A method of determining materials of lenses contained in an optical system of a projection exposure apparatus is described. First, for each lens of a plurality of the lenses, a susceptibility factor KLT/LH is determined. This factor is a measure of the susceptibility of the respective lens to deteriorations caused by at least one of lifetime effects and lens heating effects. Then a birefringent fluoride crystal is selected as a material for each lens for which the susceptibility factor KLT/LH is above a predetermined threshold. Theses lenses are assigned to a first set of lenses. For these lenses, measures are determined for reducing adverse effects caused by birefringence inherent to the fluoride crystals.
    Type: Application
    Filed: July 14, 2005
    Publication date: May 25, 2006
    Inventors: Vladimir Kamenov, Daniel Kraehmer, Michael Totzeck, Toralf Gruner, Aurelian Dodoc
  • Patent number: 6992753
    Abstract: Radiation-induced damage to a lens material in a projection exposure system is reduced by selection of maximum design fluence values HD for lenses and at least one lens made of a material having a characteristic transition point TRC after exposure to a given amount of radiation, wherein, for instance, TRC<0.8. HD among other relationships and/or characteristics of the lenses.
    Type: Grant
    Filed: December 24, 2003
    Date of Patent: January 31, 2006
    Assignee: Carl Zeiss SMT AG
    Inventors: Daniel Krähmer, Eric Eva
  • Patent number: 6992834
    Abstract: Objective (1, 601), in particular a projection objective for a microlithography projection apparatus, with first birefringent lenses (L108, L109, L129, L130) and with second birefringent lenses (L101–L107, L110–L128). The first lenses (L108, L109, L129, L130) are distinguished from the second lenses (L101–L107, L110–L128) by the lens material used or by the material orientation. After passing through the first lenses (L108, L109, L129, L130) and the second lenses (L101–L107, L110–L128), an outer aperture ray (5, 7) and a principal ray (9) are subject to optical path differences for two mutually orthogonal states of polarization. The difference between these optical path differences is smaller than 25% of the working wavelength. In at least one first lens (L129, L130), the aperture angle of the outer aperture ray (5, 7) is at least 70% of the largest aperture angle occurring for said aperture ray in all of the first lenses (L108, L109, L129, L130) and second lenses (L101–L107, L110–L128).
    Type: Grant
    Filed: March 2, 2005
    Date of Patent: January 31, 2006
    Assignee: Carl Zeiss SMT AG
    Inventors: Michael Totzeck, Vladimer Kamenov, Daniel Kraehmer, Wilhelm Ulrich
  • Publication number: 20050200966
    Abstract: Objective (1, 601), in particular a projection objective for a microlithography projection apparatus, with first birefringent lenses (L108, L109, L129, L130) and with second birefringent lenses (L101-L107, L110-L128). The first lenses (L108, L109, L129, L130) are distinguished from the second lenses (L101-L107, L110-L128) by the lens material used or by the material orientation. After passing through the first lenses (L108, L109, L129, L130) and the second lenses (L101-L107, L110-L128), an outer aperture ray (5, 7) and a principal ray (9) are subject to optical path differences for two mutually orthogonal states of polarization. The difference between these optical path differences is smaller than 25% of the working wavelength. In at least one first lens (L129, L130), the aperture angle of the outer aperture ray (5, 7) is at least 70% of the largest aperture angle occurring for said aperture ray in all of the first lenses (L108, L109, L129, L130) and second lenses (L101-L107, L110-L128).
    Type: Application
    Filed: March 2, 2005
    Publication date: September 15, 2005
    Inventors: Michael Totzeck, Vladimer Kamenov, Daniel Kraehmer, Wilhelm Ulrich
  • Publication number: 20050157401
    Abstract: Objective, in particular a projection objective for a microlithography projection-exposure installation, with at least one fluoride crystal lens. A reduction in the detrimental influence of birefringence is achieved if this lens is a (100)-lens with a lens axis which is approximately perpendicular to the {100} crystallographic planes or to the crystallographic planes equivalent thereto of the fluoride crystal. In the case of objectives with at least two fluoride crystal lenses, it is favorable if the fluoride crystal lenses are arranged such that they are rotated with respect to one another. The lens axes of the fluoride crystal lenses may in this case point not only in the <100> crystallographic direction but also in the <111> crystallographic direction or in the <110> crystallographic direction.
    Type: Application
    Filed: September 1, 2004
    Publication date: July 21, 2005
    Inventors: Aksel Goehnermeier, Alexandra Pazidis, Birgit Kuerz, Christoph Zaczek, Daniel Kraehmer
  • Publication number: 20050146798
    Abstract: An optical system of a microlithographic exposure apparatus comprises at least one optical element (L1 to L16, 15, 16, 24) having a locally varying birefringence direction distribution that is caused by stress-induced birefringence and is at least substantially rotationally symmetrical. At least one birefringent correcting element (K1, K2; K?) is made of a crystal having a location independent birefringence direction distribution that is at least substantially rotationally symmetrical. The crystal has a crystal lattice orientation that is oriented such that its birefringence direction distribution is at least substantially perpendicular to the locally varying birefringence direction distribution of the at least one optical element (L1 to L16, 15, 16, 24).
    Type: Application
    Filed: November 24, 2004
    Publication date: July 7, 2005
    Inventors: Daniel Kraehmer, Wilhelm Ulrich
  • Publication number: 20050146704
    Abstract: In an exposure method for exposing a substrate which is arranged in the area of an image plane of a projection objective as well as in a projection exposure system for performing that method, output radiation directed at the substrate and having an output polarization state is produced. Through variable adjustment of the output polarization state with the aid of at least one polarization manipulation device, the output polarization state can be formed to approach a nominal output polarization state. The polarization manipulation can be performed in a control loop on the basis of polarization-optical measuring data.
    Type: Application
    Filed: September 27, 2004
    Publication date: July 7, 2005
    Inventors: Toralf Gruner, Daniel Kraehmer, Michael Totzeck, Johannes Wangler, Markus Brotsack, Nils Dieckmann, Aksel Goehnermeier, Markus Schwab, Damian Fiolka, Markus Zenzinger