Patents by Inventor Bruce W. Worster

Bruce W. Worster 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).

  • Patent number: 7384806
    Abstract: A method is described for characterizing defects on a test surface of a semiconductor wafer using a confocal-microscope-based automatic defect characterization (ADC) system. The surface to be tested and a reference surface are scanned using a confocal microscope to obtain three-dimensional images of the test and reference surfaces. The test and reference images are converted into sets of geometric constructs, or “primitives,” that are used to approximate features of the images. Next, the sets of test and reference primitives are compared to determine whether the set of test primitives is different from the set of reference primitives. If such a difference exists, then the difference data is used to generate defect parameters, which are then compared to a knowledge base of defect reference data. Based on this comparison, the ADC system characterizes the defect and estimates a degree of confidence in the characterization.
    Type: Grant
    Filed: December 21, 2006
    Date of Patent: June 10, 2008
    Assignee: KLA-Tencor Corporation
    Inventors: Bruce W. Worster, Ken K. Lee
  • Patent number: 7154605
    Abstract: A method is described for characterizing defects on a test surface of a semiconductor wafer using a confocal-microscope-based automatic defect characterization (ADC) system. The surface to be tested and a reference surface are scanned using a confocal microscope to obtain three-dimensional images of the test and reference surfaces. The test and reference images are converted into sets of geometric constructs, or “primitives,” that are used to approximate features of the images. Next, the sets of test and reference primitives are compared to determine whether the set of test primitives is different from the set of reference primitives. If such a difference exists, then the difference data is used to generate defect parameters, which are then compared to a knowledge base of defect reference data. Based on this comparison, the ADC system characterizes the defect and estimates a degree of confidence in the characterization.
    Type: Grant
    Filed: May 8, 2003
    Date of Patent: December 26, 2006
    Assignee: KLA-Tencor Corporation
    Inventors: Bruce W. Worster, Ken K. Lee
  • Patent number: 6661515
    Abstract: A method is described for characterizing defects on a test surface of a semiconductor wafer using a confocal-microscope-based automatic defect characterization (ADC) system. The surface to be tested and a reference surface are scanned using a confocal microscope to obtain three-dimensional images of the test and reference surfaces. The test and reference images are converted into sets of geometric constructs, or “primitives,” that are used to approximate features of the images. Next, the sets of test and reference primitives are compared to determine whether the set of test primitives is different from the set of reference primitives. If such a difference exists, then the difference data is used to generate defect parameters, which are then compared to a knowledge base of defect reference data. Based on this comparison, the ADC system characterizes the defect and estimates a degree of confidence in the characterization.
    Type: Grant
    Filed: September 11, 2001
    Date of Patent: December 9, 2003
    Assignee: KLA-Tencor Corporation
    Inventors: Bruce W. Worster, Ken K. Lee
  • Publication number: 20030203520
    Abstract: A method is described for characterizing defects on a test surface of a semiconductor wafer using a confocal-microscope-based automatic defect characterization (ADC) system. The surface to be tested and a reference surface are scanned using a confocal microscope to obtain three-dimensional images of the test and reference surfaces. The test and reference images are converted into sets of geometric constructs, or “primitives,” that are used to approximate features of the images. Next, the sets of test and reference primitives are compared to determine whether the set of test primitives is different from the set of reference primitives. If such a difference exists, then the difference data is used to generate defect parameters, which are then compared to a knowledge base of defect reference data. Based on this comparison, the ADC system characterizes the defect and estimates a degree of confidence in the characterization.
    Type: Application
    Filed: May 8, 2003
    Publication date: October 30, 2003
    Inventors: Bruce W. Worster, Ken K. Lee
  • Publication number: 20020012118
    Abstract: A method is described for characterizing defects on a test surface of a semiconductor wafer using a confocal-microscope-based automatic defect characterization (ADC) system. The surface to be tested and a reference surface are scanned using a confocal microscope to obtain three-dimensional images of the test and reference surfaces. The test and reference images are converted into sets of geometric constructs, or “primitives,” that are used to approximate features of the images. Next, the sets of test and reference primitives are compared to determine whether the set of test primitives is different from the set of reference primitives. If such a difference exists, then the difference data is used to generate defect parameters, which are then compared to a knowledge base of defect reference data. Based on this comparison, the ADC system characterizes the defect and estimates a degree of confidence in the characterization.
    Type: Application
    Filed: September 11, 2001
    Publication date: January 31, 2002
    Inventors: Bruce W. Worster, Ken K. Lee
  • Patent number: 6288782
    Abstract: A method is described for characterizing defects on a test surface of a semiconductor wafer using a confocal-microscope-based automatic defect characterization (ADC) system. The surface to be tested and a reference surface are scanned using a confocal microscope to obtain three-dimensional images of the test and reference surfaces. The test and reference images are converted into sets of geometric constructs, or “primitives,” that are used to approximate features of the images. Next, the sets of test and reference primitives are compared to determine whether the set of test primitives is different from the set of reference primitives. If such a difference a exists, then the difference data is used to generate defect parameters, which are then compared to a knowledge base of defect reference data. Based on this comparison, the ADC system characterizes the defect and estimates a degree of confidence in the characterization.
    Type: Grant
    Filed: May 5, 1999
    Date of Patent: September 11, 2001
    Assignee: Ultrapointe Corporation
    Inventors: Bruce W. Worster, Ken K. Lee
  • Patent number: 6167148
    Abstract: An improved wafer surface inspection system is disclosed. In one embodiment, the object surface inspection system includes a translation stage that generates relative motion between an object viewing device such as an objective lens and the surface of the object being inspected. A translation stage controller controls the relative movement of the object surface and the object viewing device. The translation stage controller determines current coordinates for the object surface and the object viewing device, compares the current coordinates to target coordinates generated by a processor, and generates a trigger signal in response to a match between the current coordinates to the target coordinates. A camera receives an image through the object viewing device and captures the image in response to the trigger signal while the translation stage generates relative motion between the object surface and the object viewing device.
    Type: Grant
    Filed: June 30, 1998
    Date of Patent: December 26, 2000
    Assignee: Ultrapointe Corporation
    Inventors: Louis D. Calitz, Kexing Cecilia Du, M. Kent Norton, Bruce W. Worster
  • Patent number: 5963314
    Abstract: A laser imaging system is used to analyze defects on semiconductor wafers that have been detected by patterned wafer defect detecting systems (wafer scanners). The laser imaging system replaces optical microscope review stations now utilized in the semiconductor fab environment to examine detected optical anomalies that may represent wafer defects. In addition to analyzing defects, the laser imaging system can perform a variety of microscopic inspection functions including defect detection and metrology. The laser imaging system uses confocal laser scanning microscopy techniques, and operates under class 1 cleanroom conditions and without exposure of the wafers to operator contamination or airflow.
    Type: Grant
    Filed: October 15, 1996
    Date of Patent: October 5, 1999
    Assignee: Ultrapointe Corporation
    Inventors: Bruce W. Worster, Dale E. Crane, Hans J. Hansen, Christopher R. Fairley, Ken K. Lee
  • Patent number: 5923430
    Abstract: A method is described for characterizing defects on a test surface of a semiconductor wafer using a confocal-microscope-based automatic defect characterization (ADC) system. The surface to be tested and a reference surface are scanned using a confocal microscope to obtain three-dimensional images of the test and reference surfaces. The test and reference images are converted into sets of geometric constructs, or "primitives," that are used to approximate features of the images. Next, the sets of test and reference primitives are compared to determine whether the set of test primitives is different from the set of reference primitives. If such a difference exists, then the difference data is used to generate defect parameters, which are then compared to a knowledge base of defect reference data. Based on this comparison, the ADC system characterizes the defect and estimates a degree of confidence in the characterization.
    Type: Grant
    Filed: February 3, 1997
    Date of Patent: July 13, 1999
    Assignee: Ultrapointe Corporation
    Inventors: Bruce W. Worster, Ken K. Lee
  • Patent number: 5808735
    Abstract: 10A method is described for detecting and characterizing defects on a test surface of a semiconductor wafer. A three-dimensional image of the test surface is aligned and compared with a three-dimensional image of a defect-free reference surface. Intensity differences between corresponding pixels in the two images that exceed a predefined threshold value are deemed defect pixels. According to the method, the pixels of the reference image are grouped according to their respective z values (elevation) to identify different physical layers of the reference surface. Because different surface layers can have different image properties, such as reflectance and image texture, the groups of pixels are analyzed separately to determine an optimal threshold value for each of the groups, and therefore for each layer of the reference surface.
    Type: Grant
    Filed: November 26, 1996
    Date of Patent: September 15, 1998
    Assignee: Ultrapointe Corporation
    Inventors: Ken K. Lee, Ke Han, Lakshman Srinivasan, Bruce W. Worster
  • Patent number: 5479252
    Abstract: A laser imaging system is used to analyze defects on semiconductor wafers that have been detected by patterned wafer defect detecting systems (wafer scanners). The laser imaging system replaces optical microscope review stations now utilized in the semiconductor fab environment to examine detected optical anomalies that may represent wafer defects. In addition to analyzing defects, the laser imaging system can perform a variety of microscopic inspection functions including defect detection and metrology. The laser imaging system uses confocal laser scanning microscopy techniques, and operates under class 1 cleanroom conditions and without exposure of the wafers to operator contamination or airflow.
    Type: Grant
    Filed: June 17, 1993
    Date of Patent: December 26, 1995
    Assignee: Ultrapointe Corporation
    Inventors: Bruce W. Worster, Dale E. Crane, Hans J. Hansen, Christopher R. Fairley, Ken K. Lee