Patents by Inventor Lakshman Srinivasan

Lakshman Srinivasan 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: 7761182
    Abstract: A repair system for flat panel display (FPD) substrates performs a number of operations, such as automatic image capture and processing, automatic defect classification, automatic repair classification, and repair macro (instruction) generation software. Defect classification, repair classification, and repair macro generation are based on an open architecture and can address any number of use-cases through the use of multi-tiered classifiers, and thus a wide variety of panel designs may be repaired within a single repair tool. The multi-tiered set of classifiers, e.g., defect classifier, repair classifier, enables an efficient decision-making repair process with capability for customization. The multi-tiered classifiers are optionally extended to support statistical learning (both online & batch) and active learning, in the context of a supporting database of defects and associated tools.
    Type: Grant
    Filed: January 20, 2006
    Date of Patent: July 20, 2010
    Assignee: Photon Dynamics, Inc.
    Inventors: Harry Gallarda, Steven Barnes, Lakshman Srinivasan, Wayne Wang
  • Publication number: 20060226865
    Abstract: A repair system for flat panel display (FPD) substrates performs a number of operations, such as automatic image capture and processing, automatic defect classification, automatic repair classification, and repair macro (instruction) generation software. Defect classification, repair classification, and repair macro generation are based on an open architecture and can address any number of use-cases through the use of multi-tiered classifiers, and thus a wide variety of panel designs may be repaired within a single repair tool. The multi-tiered set of classifiers, e.g., defect classifier, repair classifier, enables an efficient decision-making repair process with capability for customization. The multi-tiered classifiers are optionally extended to support statistical learning (both online & batch) and active learning, in the context of a supporting database of defects and associated tools.
    Type: Application
    Filed: January 20, 2006
    Publication date: October 12, 2006
    Applicant: Photon Dynamics, Inc.
    Inventors: Harry Gallarda, Steven Barnes, Lakshman Srinivasan, Wayne Wang
  • Patent number: 7065239
    Abstract: A method and system for defect inspection of microfabricated structures such as semiconductor wafers, masks or reticles for micro-fabrication, flat panel displays, micro-electro-mechanical (MEMs) having repetitive array regions such as memories or pixels. In one embodiment a method of inspection of microfabricated structures includes the steps of acquiring contrast data or images from the microfabricated structures, analyzing automatically the contrast data or images to find repetitive regions of the contrast data and comparing the repetitive regions of the contrast data with reference data to detect defects in the microfabricated structures. In the analyzing step, a cell-metric such as the range, or mean or other statistical or mathematical measure of the contrast data is used to find the repetitive regions. Image or contrast data acquisition can be performed with an optical, e-beam or other microscope suited for microfabricated structures.
    Type: Grant
    Filed: October 24, 2001
    Date of Patent: June 20, 2006
    Assignee: Applied Materials, Inc.
    Inventors: Kais Jameel Maayah, Harry Stanton Gallarda, Jr., Lakshman Srinivasan, Richard Barnard, Jun Liu
  • Publication number: 20030076989
    Abstract: A method and system for defect inspection of microfabricated structures such as semiconductor wafers, masks or reticles for micro-fabrication, flat panel displays, micro-electro-mechanical (MEMs) having repetitive array regions such as memories or pixels. In one embodiment a method of inspection of microfabricated structures includes the steps of acquiring contrast data or images from the microfabricated structures, analyzing automatically the contrast data or images to find repetitive regions of the contrast data and comparing the repetitive regions of the contrast data with reference data to detect defects in the microfabricated structures. In the analyzing step, a cell-metric such as the range, or mean or other statistical or mathematical measure of the contrast data is used to find the repetitive regions. Image or contrast data acquisition can be performed with an optical, e-beam or other microscope suited for microfabricated structures.
    Type: Application
    Filed: October 24, 2001
    Publication date: April 24, 2003
    Inventors: Kais Jameel Maayah, Harry Stanton Gallarda, Lakshman Srinivasan, Richard Barnard, Jun Liu
  • 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: 5798830
    Abstract: A method is described for optimizing intensity-comparison thresholds used to compare test and reference images for defect detection. 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 27, 1996
    Date of Patent: August 25, 1998
    Assignee: Ultrapointe Corporation
    Inventor: Lakshman Srinivasan