Patents by Inventor Albert Kreh

Albert Kreh 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: 20050168729
    Abstract: The invention concerns a method for inspecting the surface of a wafer, having at least a first and a second incident illumination device in order to emit respectively a first and a second incident illuminating light beam and to illuminate a region on the surface, and having at least one image sensing device in order to sense an image of the illuminated region, the first incident illumination device and the at least one image sensing device being arranged so that images of the illuminated region can be sensed in a bright-field configuration, and the second incident illumination device and the at least one image sensing device being arranged so that images of the illuminated region can be sensed in a dark-field configuration. A control device for controlling the first and the second incident illumination device and the at least one image sensing device is furthermore provided.
    Type: Application
    Filed: January 27, 2005
    Publication date: August 4, 2005
    Applicant: Leica Microsystems Semiconductor GmbH
    Inventors: Paul Jung, Albert Kreh, Henning Backhauss
  • Publication number: 20050134839
    Abstract: Defects on a wafer (26) can be detected using bright-field and/or dark-field illumination. The radiation incident onto the wafer (26) has, in this context, a substantial influence on the reliability of the measurement results. To improve the reliability of the measurement results, the wafer (26) is illuminated with an illumination device (12), adjustment of the illumination device (12), in particular its brightness and frequency, being accomplished in consideration of read-out stored illumination setpoints. These illumination setpoints are determined by way of a previous reference measurement.
    Type: Application
    Filed: December 15, 2004
    Publication date: June 23, 2005
    Inventors: Albert Kreh, Henning Backhauss, Detlef Michelsson
  • Publication number: 20050134846
    Abstract: The apparatus encompasses at least one stroboscopic incident-light illumination device for emitting a pulsed illuminating light beam onto a surface of the wafer and for illuminating a region on the surface of the wafer; and having at least one image acquisition device for acquiring an image of the respectively illuminated region on the surface of the wafer. The apparatus is characterized, according to the present invention, in that by at least one photodetection device for sensing light of the respective illuminating light beam, and a control device for controlling an image acquisition operation on the basis of the light sensed by the photodetection device, are provided. Intensity fluctuations of the light flashes of the incident-light illumination device are compensated for either by normalizing image data of the illuminated region or by controlling the duration of the light flashes.
    Type: Application
    Filed: December 15, 2004
    Publication date: June 23, 2005
    Inventors: Albert Kreh, Henning Backhauss
  • Publication number: 20050101036
    Abstract: A system for the detection of macrodefects is disclosed, the system being surrounded by a housing (50) and being subdivided into a first segment (6), a second segment (8), and a third segment (10). Provided in the second segment (8) is a stage (2), displaceable in the X direction and Y direction, on which a wafer (25) is placed. Located in the first segment (6) is an aspiration device (36) that directs aspirated air via an air guide (37) into the second segment (8), the air guide (37) encompassing several air-directing panels (38) so that an air flow (60) is guided in parallel fashion over the wafer (25).
    Type: Application
    Filed: November 2, 2004
    Publication date: May 12, 2005
    Inventors: Albert Kreh, Henning Backhauss, Rene Schenck
  • Patent number: 6875972
    Abstract: The autofocus module possesses, between the detector element (43) and the optical means, a cylindrical lens (42) that, for determination of the focus position, generates a line on the detector element (43). In addition, the detector element (43) is pivotable about an axis in such a way that it is inclined with respect to a plane defined by the surface of the specimen (20), and its inclination is adjustable. All the optical components of the autofocus module are combined in a housing (25) that can be quickly flange-mounted onto an existing microscope-based system (1).
    Type: Grant
    Filed: July 23, 2003
    Date of Patent: April 5, 2005
    Assignee: Leica Microsystems Wetzlar GmbH
    Inventor: Albert Kreh
  • Publication number: 20050002021
    Abstract: The invention concerns an apparatus for inspection of a wafer, encompassing at least one illumination device in order to radiate an illuminating light beam onto a surface of the wafer, and an image capture device in order to capture an image of an illuminated region on the surface of the wafer in a plurality of spectral regions, a color modification device being provided in order to modify the color spectrum of the illuminating light beam or of the reflected light beam. The wafer inspection apparatus is characterized in that the color modification device is designed in such a way that the color spectrum of the illuminating light beam, or that of the image that is acquired of the surface of the wafer, is adaptable to the spectral sensitivity of the image capture device.
    Type: Application
    Filed: June 30, 2004
    Publication date: January 6, 2005
    Inventors: Albert Kreh, Henning Backhauss
  • Publication number: 20050001900
    Abstract: The invention concerns an apparatus for inspection of a wafer, encompassing at least two incident-light illumination devices that radiate a respective illuminating light beam which is incident obliquely onto the surface of a wafer to be inspected and respectively defines an illumination axis, an image capture device for capturing an image of the surface in a dark-field arrangement, and a wafer receiving device for receiving the wafer, on whose surface linearly extending features are configured, in a definable orientation. The apparatus is characterized in that the illumination axes are oriented perpendicular to one another, and the apparatus is designed in such a way that a projection of the respective illumination axis onto the surface of the wafer is oriented substantially perpendicular to respective linear features on the surface of the wafer. With the apparatus, macrodefects can be detected and the quality of the edge profile of features configured on the surface of the wafer can be assessed.
    Type: Application
    Filed: June 30, 2004
    Publication date: January 6, 2005
    Inventors: Albert Kreh, Henning Backhauss
  • Publication number: 20050002023
    Abstract: The invention concerns an apparatus for inspection of a wafer, encompassing at least one incident-light illumination device that radiates an illuminating light beam which is incident obliquely onto a surface of a wafer to be inspected, and an image capture device for capturing an image of the surface in a dark-field arrangement. The wafer inspection apparatus is characterized in that at least one deflection device is provided in order to deflect an associated illuminating light beam onto the surface of the wafer.
    Type: Application
    Filed: May 27, 2004
    Publication date: January 6, 2005
    Inventors: Albert Kreh, Henning Backhauss
  • Publication number: 20040239920
    Abstract: An apparatus for wafer inspection is described, comprising an incident-light illumination device (5) having an illumination axis and an imaging device (9) having an image axis, both of which are inclined with respect to one another and are directed onto a region to be inspected of the surface (42) of a wafer (2). According to the present invention, the apparatus is characterized in that the incident-light illumination device (5) and the imaging device (9, 19) each have associated with them a polarizing means whose transmission axes are oriented at a predetermined angle to one another.
    Type: Application
    Filed: May 17, 2004
    Publication date: December 2, 2004
    Applicant: LEICA MICROSYSTEMS SEMICONDUCTOR GmbH
    Inventors: Albert Kreh, Henning Backhauss
  • Patent number: 6812446
    Abstract: An autofocus module (30) for a microscope-based system (1) is equipped in such a way that a light source (31) which generates a measurement light bundle (32) is provided. A first axicon (34a) generates an eccentrically extending annularly divergent measurement light beam bundle (32a). A second axicon (34a) is provided in order to parallelize the remitted divergent measurement light beam bundle (32b). A differential diode (42) is mounted in the module (30) for determination of the focus position.
    Type: Grant
    Filed: July 23, 2003
    Date of Patent: November 2, 2004
    Assignee: Leica Microsystems Semiconductor GmbH
    Inventor: Albert Kreh
  • Publication number: 20040135061
    Abstract: An autofocus module (30) for a microscope-based system (1) is equipped in such a way that a light source (31) which generates a measurement light bundle (32) is provided. A first axicon (34a) generates an eccentrically extending annularly divergent measurement light beam bundle (32a). A second axicon (34a) is provided in order to parallelize the remitted divergent measurement light beam bundle (32b). A differential diode (42) is mounted in the module (30) for determination of the focus position.
    Type: Application
    Filed: July 23, 2003
    Publication date: July 15, 2004
    Inventor: Albert Kreh
  • Publication number: 20040124334
    Abstract: The autofocus module possesses, between the detector element (43) and the optical means, a cylindrical lens (42) that, for determination of the focus position, generates a line on the detector element (43). In addition, the detector element (43) is pivotable about an axis in such a way that it is inclined with respect to a plane defined by the surface of the specimen (20), and its inclination is adjustable. All the optical components of the autofocus module are combined in a housing (25) that can be quickly flange-mounted onto an existing microscope-based system (1).
    Type: Application
    Filed: July 23, 2003
    Publication date: July 1, 2004
    Inventor: Albert Kreh