Patents by Inventor Jagdish Chandra SARASWATULA

Jagdish Chandra SARASWATULA 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: 11119060
    Abstract: Defect location accuracy can be increased using shape based grouping with pattern-based defect centering. Design based grouping of defects on a wafer can be performed. A spatial distribution of the defects around at least one structure on the wafer, such as a predicted hot spot, can be determined. At least one design based defect property for a location around the structure can be determined. The defects within an x-direction threshold and a y-direction threshold of the structure may be prioritized.
    Type: Grant
    Filed: February 25, 2018
    Date of Patent: September 14, 2021
    Assignee: KLA-Tencor Corporation
    Inventors: Jagdish Chandra Saraswatula, Martin Plihal
  • Patent number: 11035666
    Abstract: Systems and methods for determining location of critical dimension (CD) measurement or inspection are disclosed. Real-time selection of locations to take critical dimension measurements based on potential impact of critical dimension variations at the locations can be performed. The design of a semiconductor device also can be used to predict locations that may be impacted by critical dimension variations. Based on an ordered location list, which can include ranking or criticality, critical dimension can be measured at selected locations. Results can be used to refine a critical dimension location prediction model.
    Type: Grant
    Filed: February 25, 2018
    Date of Patent: June 15, 2021
    Assignee: KLA-Tencor Corporation
    Inventors: Jagdish Chandra Saraswatula, Arpit Yati, Hari Pathangi
  • Publication number: 20210158498
    Abstract: A method for providing a trained defect candidate detection algorithm includes: acquiring an optical image of a processed wafer; receiving a multi-beam scanning electron microscope (MSEM) image; covering a portion of the processed wafer corresponding to a portion of the optical image; and training a defect candidate detection algorithm based on the optical image and a result of an analysis of the MSEM image with regard to defect candidates. A wafer inspection method and an optical inspector using the trained defect candidate detection algorithm are disclosed.
    Type: Application
    Filed: November 22, 2019
    Publication date: May 27, 2021
    Inventor: Jagdish Chandra Saraswatula
  • Publication number: 20210073976
    Abstract: Wafer inspection methods and systems include converting an acquired image to a polygonal chain representation. The polygonal chain representation is converted to feature vectors. The feature vectors are compared to further feature vectors obtained based on design data.
    Type: Application
    Filed: September 9, 2019
    Publication date: March 11, 2021
    Inventors: Jagdish Chandra Saraswatula, Philipp Huethwohl
  • Patent number: 10901391
    Abstract: A method includes controlling a multi-scanning electron microscope, mSEM, to capture a first image of a wafer attached to a motorized handling stage while the motorized handling stage is in a first position. The first image includes at least a part of a notch of the wafer. The method also includes determining a radial axis of the wafer based on the first image, and controlling the motorized handling stage to shift the wafer along the radial axis by half a diameter of the wafer so that the motorized handling stage is in a second position. The method further includes controlling the mSEM to capture a second image of the wafer while the motorized handling stage is in the second position. The second image includes wafer structures.
    Type: Grant
    Filed: September 9, 2019
    Date of Patent: January 26, 2021
    Assignee: Carl Zeiss SMT GmbH
    Inventors: Jagdish Chandra Saraswatula, Jens Timo Neumann, Philipp Huethwohl, Thomas Korb, Raghavendra Hanumantha Nayak
  • Publication number: 20200402863
    Abstract: An optical tool is used to define critical regions in a wafer including a plurality of dies manufactured with different process parameters. An mSEM is used to scan the critical regions.
    Type: Application
    Filed: September 9, 2019
    Publication date: December 24, 2020
    Inventors: Jagdish Chandra Saraswatula, Raghavendra Hanumantha Nayak, Thomas Korb
  • Patent number: 10714366
    Abstract: Methods and systems for shape metric based scoring of wafer locations are provided. One method includes selecting shape based grouping (SBG) rules for at least two locations on a wafer. For one of the wafer locations, the selecting step includes modifying distances between geometric primitives in a design for the wafer with metrology data for the one location and determining metrical complexity (MC) scores for SBG rules associated with the geometric primitives in a field of view centered on the one location based on the distances. The selecting step also includes selecting one of the SBG rules for the one location based on the MC scores. The method also includes sorting the at least two locations on the wafer based on the SBG rule selected for the at least two locations.
    Type: Grant
    Filed: April 4, 2019
    Date of Patent: July 14, 2020
    Assignee: KLA-Tencor Corp.
    Inventors: Saibal Banerjee, Jagdish Chandra Saraswatula
  • Patent number: 10503078
    Abstract: Techniques are provided that can select defects based on criticality of design pattern as well as defect attributes for process window qualification (PWQ). Defects are sorted into categories based on process conditions and similarity of design. Shape based grouping can be performed on the random defects. Highest design based grouping scores can be assigned to the bins, which are then sorted. Particular defects can be selected from the bins. These defects may be reviewed.
    Type: Grant
    Filed: February 23, 2018
    Date of Patent: December 10, 2019
    Assignee: KLA-Tencor Corporation
    Inventors: Jagdish Chandra Saraswatula, Saibal Banerjee, Ashok Kulkarni
  • Publication number: 20190318949
    Abstract: Methods and systems for shape metric based scoring of wafer locations are provided. One method includes selecting shape based grouping (SBG) rules for at least two locations on a wafer. For one of the wafer locations, the selecting step includes modifying distances between geometric primitives in a design for the wafer with metrology data for the one location and determining metrical complexity (MC) scores for SBG rules associated with the geometric primitives in a field of view centered on the one location based on the distances. The selecting step also includes selecting one of the SBG rules for the one location based on the MC scores. The method also includes sorting the at least two locations on the wafer based on the SBG rule selected for the at least two locations.
    Type: Application
    Filed: April 4, 2019
    Publication date: October 17, 2019
    Inventors: Saibal Banerjee, Jagdish Chandra Saraswatula
  • Publication number: 20190279914
    Abstract: Processes to generate regions of interest for critical dimension uniformity measurement are disclosed. A pattern description based on historical data or a coordinate may be used as input. A pattern of interest can be determined, and then a region of interest can be determined. Instructions can be sent to a wafer inspection tool to image the region of interest on the semiconductor wafer.
    Type: Application
    Filed: July 20, 2018
    Publication date: September 12, 2019
    Inventors: Jagdish Chandra Saraswatula, Hari Pathangi Sriraman, Arpit Yati
  • Publication number: 20190072858
    Abstract: Techniques are provided that can select defects based on criticality of design pattern as well as defect attributes for process window qualification (PWQ). Defects are sorted into categories based on process conditions and similarity of design. Shape based grouping can be performed on the random defects. Highest design based grouping scores can be assigned to the bins, which are then sorted. Particular defects can be selected from the bins. These defects may be reviewed.
    Type: Application
    Filed: February 23, 2018
    Publication date: March 7, 2019
    Inventors: Jagdish Chandra SARASWATULA, Saibal BANERJEE, Ashok KULKARNI
  • Publication number: 20190072505
    Abstract: Defect location accuracy can be increased using shape based grouping with pattern-based defect centering. Design based grouping of defects on a wafer can be performed. A spatial distribution of the defects around at least one structure on the wafer, such as a predicted hot spot, can be determined. At least one design based defect property for a location around the structure can be determined. The defects within an x-direction threshold and a y-direction threshold of the structure may be prioritized.
    Type: Application
    Filed: February 25, 2018
    Publication date: March 7, 2019
    Inventors: Jagdish Chandra SARASWATULA, Martin PLIHAL
  • Publication number: 20190041202
    Abstract: Systems and methods for determining location of critical dimension (CD) measurement or inspection are disclosed. Real-time selection of locations to take critical dimension measurements based on potential impact of critical dimension variations at the locations can be performed. The design of a semiconductor device also can be used to predict locations that may be impacted by critical dimension variations. Based on an ordered location list, which can include ranking or criticality, critical dimension can be measured at selected locations. Results can be used to refine a critical dimension location prediction model.
    Type: Application
    Filed: February 25, 2018
    Publication date: February 7, 2019
    Inventors: Jagdish Chandra SARASWATULA, Arpit YATI, Hari PATHANGI