Patents by Inventor Grace H. Chen

Grace H. Chen 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: 10921262
    Abstract: Disclosed are apparatus and methods for inspecting a sample. Locations corresponding to candidate defect events on a sample are provided from an inspector operable to acquire optical images from which such candidate defect events are detected at their corresponding locations across the sample. High-resolution images are acquired from a high-resolution inspector of the candidate defect events at their corresponding locations on the sample. Each of a set of modelled optical images, which have been modeled from a set of the acquired high-resolution images, is correlated with corresponding ones of a set of the acquired optical images, to identify surface noise events, as shown in the set of high-resolution images, as sources for the corresponding candidate events in the set of acquired optical images. Otherwise, a subsurface event is identified as a likely source for a corresponding candidate defect event.
    Type: Grant
    Filed: May 28, 2020
    Date of Patent: February 16, 2021
    Assignee: KLA-Tencor Corporation
    Inventors: Qiang Zhang, Grace H. Chen
  • Publication number: 20200292468
    Abstract: Disclosed are apparatus and methods for inspecting a sample. Locations corresponding to candidate defect events on a sample are provided from an inspector operable to acquire optical images from which such candidate defect events are detected at their corresponding locations across the sample. High-resolution images are acquired from a high-resolution inspector of the candidate defect events at their corresponding locations on the sample. Each of a set of modelled optical images, which have been modeled from a set of the acquired high-resolution images, is correlated with corresponding ones of a set of the acquired optical images, to identify surface noise events, as shown in the set of high-resolution images, as sources for the corresponding candidate events in the set of acquired optical images. Otherwise, a subsurface event is identified as a likely source for a corresponding candidate defect event.
    Type: Application
    Filed: May 28, 2020
    Publication date: September 17, 2020
    Applicant: KLA-Tencor Corporation
    Inventors: Qiang Zhang, Grace H. Chen
  • Patent number: 10697900
    Abstract: Disclosed are apparatus and methods for inspecting a semiconductor sample. Locations corresponding to candidate defect events on a semiconductor sample are provided from an optical inspector operable to acquire optical images from which such candidate defect events are detected at their corresponding locations across the sample. High-resolution images are acquired from a high-resolution inspector of the candidate defect events at their corresponding locations on the sample. Each of a set of modelled optical images, which have been modeled from a set of the acquired high-resolution images, is correlated with corresponding ones of a set of the acquired optical images, to identify surface noise events, as shown in the set of high-resolution images, as sources for the corresponding candidate events in the set of acquired optical images. Otherwise, a subsurface event is identified as a likely source for a corresponding candidate defect event.
    Type: Grant
    Filed: April 25, 2019
    Date of Patent: June 30, 2020
    Assignee: KLA-Tencor Corporation
    Inventors: Qiang Zhang, Grace H. Chen
  • Publication number: 20200025689
    Abstract: A semiconductor-inspection tool scans a semiconductor die using a plurality of optical modes. A plurality of defects on the semiconductor die are identified based on results of the scanning. Respective defects of the plurality of defects correspond to respective pixel sets of the semiconductor-inspection tool. The scanning fails to resolve the respective defects. The results include multi-dimensional data based on pixel intensity for the respective pixel sets, wherein each dimension of the multi-dimensional data corresponds to a distinct mode of the plurality of optical modes. A discriminant function is applied to the results to transform the multi-dimensional data for the respective pixel sets into respective scores. Based at least in part on the respective scores, the respective defects are divided into distinct classes.
    Type: Application
    Filed: February 11, 2019
    Publication date: January 23, 2020
    Inventors: Vaibhav Gaind, Grace H. Chen, Amrit Poudel, Mark S. Wang
  • Publication number: 20190383753
    Abstract: Disclosed are apparatus and methods for inspecting a semiconductor sample. Locations corresponding to candidate defect events on a semiconductor sample are provided from an optical inspector operable to acquire optical images from which such candidate defect events are detected at their corresponding locations across the sample. High-resolution images are acquired from a high-resolution inspector of the candidate defect events at their corresponding locations on the sample. Each of a set of modelled optical images, which have been modeled from a set of the acquired high-resolution images, is correlated with corresponding ones of a set of the acquired optical images, to identify surface noise events, as shown in the set of high-resolution images, as sources for the corresponding candidate events in the set of acquired optical images. Otherwise, a subsurface event is identified as a likely source for a corresponding candidate defect event.
    Type: Application
    Filed: April 25, 2019
    Publication date: December 19, 2019
    Applicant: KLA-Tencor Corporation
    Inventors: Qiang Zhang, Grace H. Chen
  • Publication number: 20180342051
    Abstract: Systems and methods increase the signal to noise ratio of optical inspection of wafers to obtain higher inspection sensitivity. The computed reference image can minimize a norm of the difference of the test image and the computed reference image. A difference image between the test image and a computed reference image is determined. The computed reference image includes a linear combination of a second set of images.
    Type: Application
    Filed: May 4, 2018
    Publication date: November 29, 2018
    Inventors: Abdurrahman Sezginer, Xiaochun Li, Pavan Kumar, Junqing Huang, Lisheng Gao, Grace H. Chen, Yalin Xiong, Hawren Fang
  • Patent number: 10132760
    Abstract: Disclosed are methods and apparatus for optimizing a mode of an inspection tool. A first image or signal for each of a plurality of first apertures of the inspection tool is obtained, and each first image or signal pertains to a defect area. For each of a plurality of combinations of the first apertures and their first images or signals, a composite image or signal is obtained. Each composite image or signal is analyzed to determine an optimum one of the combinations of the first apertures based on a defect detection characteristic of each composite image. In one aspect, determining an optimum one of the combinations of the first apertures includes selecting a set of one or more individual apertures that result in the highest signal to noise ratio for the defect area, and the method includes setting the optimum combination of the first apertures on the inspection tool and inspecting a sample using such optimum combination of the first apertures.
    Type: Grant
    Filed: July 6, 2017
    Date of Patent: November 20, 2018
    Assignee: KLA-Tencor Corporation
    Inventors: Pavel Kolchin, Richard Wallingford, Lisheng Gao, Grace H. Chen, Markus B. Huber, Robert M. Danen
  • Patent number: 9816940
    Abstract: Disclosed are methods and apparatus for detecting defects in a semiconductor sample. An inspection tool is used to collect intensity data sets at a plurality of focus settings from each of a plurality of xy positions of the sample. A polynomial equation having a plurality of coefficients is extracted for each of the xy position's collected intensity data sets as a function of focus setting. Each of the coefficients' set of values for the plurality of xy positions is represented with a corresponding coefficient image plane. A target set of coefficient image planes and a reference set of coefficient image planes are then analyzed to detect defects on the sample.
    Type: Grant
    Filed: January 19, 2016
    Date of Patent: November 14, 2017
    Assignee: KLA-Tencor Corporation
    Inventors: Grace H. Chen, Keith Buckley Wells, Markus B. Huber, Se Baek Oh
  • Publication number: 20170307545
    Abstract: Disclosed are methods and apparatus for optimizing a mode of an inspection tool. A first image or signal for each of a plurality of first apertures of the inspection tool is obtained, and each first image or signal pertains to a defect area. For each of a plurality of combinations of the first apertures and their first images or signals, a composite image or signal is obtained. Each composite image or signal is analyzed to determine an optimum one of the combinations of the first apertures based on a defect detection characteristic of each composite image. In one aspect, determining an optimum one of the combinations of the first apertures includes selecting a set of one or more individual apertures that result in the highest signal to noise ratio for the defect area, and the method includes setting the optimum combination of the first apertures on the inspection tool and inspecting a sample using such optimum combination of the first apertures.
    Type: Application
    Filed: July 6, 2017
    Publication date: October 26, 2017
    Applicant: KLA-Tencor Corporation
    Inventors: Pavel Kolchin, Richard Wallingford, Lisheng Gao, Grace H. Chen, Markus B. Huber, Robert M. Danen
  • Patent number: 9726617
    Abstract: Disclosed are methods and apparatus for optimizing a mode of an inspection tool. A first image or signal for each of a plurality of first apertures of the inspection tool is obtained, and each first image or signal pertains to a defect area. For each of a plurality of combinations of the first apertures and their first images or signals, a composite image or signal is obtained. Each composite image or signal is analyzed to determine an optimum one of the combinations of the first apertures based on a defect detection characteristic of each composite image.
    Type: Grant
    Filed: November 8, 2013
    Date of Patent: August 8, 2017
    Assignee: KLA-Tencor Corporation
    Inventors: Pavel Kolchin, Richard Wallingford, Lisheng Gao, Grace H. Chen, Markus B. Huber, Robert M. Danen
  • Patent number: 9523646
    Abstract: In an optical inspection tool, an illumination aperture is opened at each of a plurality of aperture positions of an illumination pupil area one at a time across the illumination pupil area. For each aperture opening position, an incident beam is directed towards the illumination pupil area so as to selectively pass a corresponding ray bundle of the illumination beam at a corresponding set of one or more incident angles towards the sample and an output beam, which is emitted from the sample in response to the corresponding ray bundle of the incident beam impinging on the sample at the corresponding set of one or more incident angles, is detected. A defect detection characteristic for each aperture position is determined based on the output beam detected for each aperture position. An optimum aperture configuration is determined based on the determined defect detection characteristic for each aperture position.
    Type: Grant
    Filed: May 18, 2016
    Date of Patent: December 20, 2016
    Assignee: KLA-Tencor Corporation
    Inventors: Grace H. Chen, Rudolf Brunner, Lisheng Gao, Robert M. Danen, Lu Chen
  • Publication number: 20160266047
    Abstract: In an optical inspection tool, an illumination aperture is opened at each of a plurality of aperture positions of an illumination pupil area one at a time across the illumination pupil area. For each aperture opening position, an incident beam is directed towards the illumination pupil area so as to selectively pass a corresponding ray bundle of the illumination beam at a corresponding set of one or more incident angles towards the sample and an output beam, which is emitted from the sample in response to the corresponding ray bundle of the incident beam impinging on the sample at the corresponding set of one or more incident angles, is detected. A defect detection characteristic for each aperture position is determined based on the output beam detected for each aperture position. An optimum aperture configuration is determined based on the determined defect detection characteristic for each aperture position.
    Type: Application
    Filed: May 18, 2016
    Publication date: September 15, 2016
    Applicant: KLA-Tencor Corporation
    Inventors: Grace H. Chen, Rudolf Brunner, Lisheng Gao, Robert M. Danen, Lu Chen
  • Publication number: 20160209334
    Abstract: Disclosed are methods and apparatus for detecting defects in a semiconductor sample. An inspection tool is used to collect intensity data sets at a plurality of focus settings from each of a plurality of xy positions of the sample. A polynomial equation having a plurality of coefficients is extracted for each of the xy position's collected intensity data sets as a function of focus setting. Each of the coefficients' set of values for the plurality of xy positions is represented with a corresponding coefficient image plane. A target set of coefficient image planes and a reference set of coefficient image planes are then analyzed to detect defects on the sample.
    Type: Application
    Filed: January 19, 2016
    Publication date: July 21, 2016
    Applicant: KLA-Tencor Corporation
    Inventors: Grace H. Chen, Keith Buckley Wells, Markus B. Huber, Se Baek Oh
  • Patent number: 9389166
    Abstract: Disclosed are apparatus and methods for inspecting or measuring a specimen. An incident beam is directed across a plurality of consecutive scan portions of a specimen so that an output beam profile from each scan portion is consecutively collected by a photomultiplier tube (PMT), and the scan portions include at least one or more first scan portions and a next scan portion that is scanned after the one or more first scan portions. After or while the incident beam is directed to the one or more first scan portions of the specimen, an output signal for each first scan portion is obtained based on the output beam profile that is collected by the PMT for each first scan portion. An expected output beam profile for the next scan portion is determined based on the output signal that is obtained for each one or more first scan portions.
    Type: Grant
    Filed: November 13, 2012
    Date of Patent: July 12, 2016
    Assignee: KLA-Tencor Corporation
    Inventors: Ralph C. Wolf, Grace H. Chen, Kai Cao, Jamie M. Sullivan, Paul J. Donders, Derek C. Mackay
  • Patent number: 9347891
    Abstract: In an optical inspection tool, an illumination aperture is opened at each of a plurality of aperture positions of an illumination pupil area one at a time across the illumination pupil area. For each aperture opening position, an incident beam is directed towards the illumination pupil area so as to selectively pass a corresponding ray bundle of the illumination beam at a corresponding set of one or more incident angles towards the sample and an output beam, which is emitted from the sample in response to the corresponding ray bundle of the incident beam impinging on the sample at the corresponding set of one or more incident angles, is detected. A defect detection characteristic for each aperture position is determined based on the output beam detected for each aperture position. An optimum aperture configuration is determined based on the determined defect detection characteristic for each aperture position.
    Type: Grant
    Filed: March 1, 2013
    Date of Patent: May 24, 2016
    Assignee: KLA-Tencor Corporation
    Inventors: Grace H. Chen, Rudolf Brunner, Lisheng Gao, Robert M. Danen, Lu Chen
  • Patent number: 8989479
    Abstract: The present invention includes searching imagery data in order to identify one or more patterned regions on a semiconductor wafer, generating one or more virtual Fourier filter (VFF) working areas, acquiring an initial set of imagery data from the VFF working areas, defining VFF training blocks within the identified patterned regions of the VFF working areas utilizing the initial set of imagery data, wherein each VFF training block is defined to encompass a portion of the identified patterned region displaying a selected repeating pattern, calculating an initial spectrum for each VFF training block utilizing the initial set of imagery data from the VFF training blocks, and generating a VFF for each training block by identifying frequencies of the initial spectrum having maxima in the frequency domain, wherein the VFF is configured to null the magnitude of the initial spectrum at the frequencies identified to display spectral maxima.
    Type: Grant
    Filed: August 1, 2011
    Date of Patent: March 24, 2015
    Assignee: KLA-Tencor Corporation
    Inventors: Lisheng Gao, Kenong Wu, Allen Park, Ellis Chang, Khurram Zafar, Junqing Huang, Ping Gu, Christopher Maher, Grace H. Chen, Songnian Rong, Liu-Ming Wu
  • Publication number: 20150015874
    Abstract: In an optical inspection tool, an illumination aperture is opened at each of a plurality of aperture positions of an illumination pupil area one at a time across the illumination pupil area. For each aperture opening position, an incident beam is directed towards the illumination pupil area so as to selectively pass a corresponding ray bundle of the illumination beam at a corresponding set of one or more incident angles towards the sample and an output beam, which is emitted from the sample in response to the corresponding ray bundle of the incident beam impinging on the sample at the corresponding set of one or more incident angles, is detected. A defect detection characteristic for each aperture position is determined based on the output beam detected for each aperture position. An optimum aperture configuration is determined based on the determined defect detection characteristic for each aperture position.
    Type: Application
    Filed: March 1, 2013
    Publication date: January 15, 2015
    Applicant: KLA-Tencor Corporation
    Inventors: Grace H. Chen, Rudolf Brunner, Lisheng Gao, Robert M. Danen, Lu Chen
  • Publication number: 20140354983
    Abstract: Disclosed are methods and apparatus for optimizing a mode of an inspection tool. A first image or signal for each of a plurality of first apertures of the inspection tool is obtained, and each first image or signal pertains to a defect area. For each of a plurality of combinations of the first apertures and their first images or signals, a composite image or signal is obtained. Each composite image or signal is analyzed to determine an optimum one of the combinations of the first apertures based on a defect detection characteristic of each composite image.
    Type: Application
    Filed: November 8, 2013
    Publication date: December 4, 2014
    Applicant: KLA-Tencor Corporation
    Inventors: Pavel Kolchin, Richard Wallingford, Lisheng Gao, Grace H. Chen, Markus b. Huber, Robert M. Danen
  • Publication number: 20120141013
    Abstract: The present invention includes searching imagery data in order to identify one or more patterned regions on a semiconductor wafer, generating one or more virtual Fourier filter (VFF) working areas, acquiring an initial set of imagery data from the VFF working areas, defining VFF training blocks within the identified patterned regions of the VFF working areas utilizing the initial set of imagery data, wherein each VFF training block is defined to encompass a portion of the identified patterned region displaying a selected repeating pattern, calculating an initial spectrum for each VFF training block utilizing the initial set of imagery data from the VFF training blocks, and generating a VFF for each training block by identifying frequencies of the initial spectrum having maxima in the frequency domain, wherein the VFF is configured to null the magnitude of the initial spectrum at the frequencies identified to display spectral maxima.
    Type: Application
    Filed: August 1, 2011
    Publication date: June 7, 2012
    Applicant: KLA-TENCOR CORPORATION
    Inventors: Lisheng Gao, Kenong Wu, Allen Park, Ellis Chang, Khurram Zafar, Junqing Huang, Ping Gu, Christopher Maher, Grace H. Chen, Songnian Rong, Liu-Ming Wu
  • Patent number: 7505619
    Abstract: A dark field surface inspection tool and system are disclosed herein. The tool includes an illumination source capable of scanning a light beam onto an inspection surface. Light scattered by each inspection point is captured as image data by a photo detector array arranged at a fourier plane. The images captured are adaptively filtered to remove a portion of the bright pixels from the images to generate filtered images. The filtered images are then analyzed to detect defects in the inspection surface. Methods of the invention include using die-to-die comparison to identify bright portions of scattering patterns and generate unique image filters associated with those patterns. The associated images are then filtered to generate filtered images which are then used to detect defects. Also, data models of light scattering behavior can be used to generate filters.
    Type: Grant
    Filed: December 20, 2005
    Date of Patent: March 17, 2009
    Assignee: KLA-Tencor Technologies Corporation
    Inventors: Evan R. Mapoles, Grace H. Chen, Christopher F. Bevis, David W. Shortt