Patents by Inventor Hawren Fang

Hawren Fang 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: 11468553
    Abstract: A system for characterizing a specimen is disclosed. In one embodiment, the system includes a controller configured to: receive training images of one or more defects of the specimen; generate a machine learning classifier based on the training images; receive product images of one or more defects of a specimen; determine one or more defect type classifications of one or more defects with the machine learning classifier; filter the product images with one or more smoothing filters; perform binarization processes to generate binarized product images; perform morphological image processing operations on the binarized product images; determine one or more algorithm-estimated defect sizes of the one or more defects based on the binarized product images; and determine one or more refined estimates of one or more defect sizes of the one or more defects based on the one or more algorithm-estimated defect sizes and the one or more defect type classifications.
    Type: Grant
    Filed: September 17, 2019
    Date of Patent: October 11, 2022
    Assignee: KLA Corporation
    Inventors: Ramaprasad Kulkarni, Ge Cong, Hawren Fang
  • Publication number: 20220084179
    Abstract: Disclosed are methods and apparatus for inspecting a photolithographic reticle. A plurality of reference far field images are simulated by inputting a plurality of reference near field images into a physics-based model, and the plurality of reference near field images are generated by a trained deep learning model from a test portion of the design database that was used to fabricate a test area of a test reticle. The test area of a test reticle, which was fabricated from the design database, is inspected for defects via a die-to-database process that includes comparing the plurality of reference far field reticle images simulated by the physic-based model to a plurality of test images acquired by the inspection system from the test area of the test reticle.
    Type: Application
    Filed: November 24, 2021
    Publication date: March 17, 2022
    Applicant: KLA-Tencor Corporation
    Inventors: Hawren Fang, Abdurrahman Sezginer, Rui-fang Shi
  • Patent number: 11270430
    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: Grant
    Filed: May 4, 2018
    Date of Patent: March 8, 2022
    Assignee: KLA-TENCOR CORPORATION
    Inventors: Abdurrahman Sezginer, Xiaochun Li, Pavan Kumar, Junqing Huang, Lisheng Gao, Grace H. Chen, Yalin Xiong, Hawren Fang
  • Patent number: 11257207
    Abstract: Disclosed are methods and apparatus for inspecting a photolithographic reticle. A near field reticle image is generated via a deep learning process based on a reticle database image produced from a design database, and a far field reticle image is simulated at an image plane of an inspection system via a physics-based process based on the near field reticle image. The deep learning process includes training a deep learning model based on minimizing differences between the far field reticle images and a plurality of corresponding training reticle images acquired by imaging a training reticle fabricated from the design database, and such training reticle images are selected for pattern variety and are defect-free.
    Type: Grant
    Filed: November 27, 2018
    Date of Patent: February 22, 2022
    Assignee: KLA-TENCOR CORPORATION
    Inventors: Hawren Fang, Abdurrahman Sezginer, Rui-fang Shi
  • Publication number: 20200143528
    Abstract: A system for characterizing a specimen is disclosed. In one embodiment, the system includes a controller configured to: receive training images of one or more defects of the specimen; generate a machine learning classifier based on the training images; receive product images of one or more defects of a specimen; determine one or more defect type classifications of one or more defects with the machine learning classifier; filter the product images with one or more smoothing filters; perform binarization processes to generate binarized product images; perform morphological image processing operations on the binarized product images; determine one or more algorithm-estimated defect sizes of the one or more defects based on the binarized product images; and determine one or more refined estimates of one or more defect sizes of the one or more defects based on the one or more algorithm-estimated defect sizes and the one or more defect type classifications.
    Type: Application
    Filed: September 17, 2019
    Publication date: May 7, 2020
    Inventors: Ramaprasad Kulkarni, Ge Cong, Hawren Fang
  • Publication number: 20190206041
    Abstract: Disclosed are methods and apparatus for inspecting a photolithographic reticle. A near field reticle image is generated via a deep learning process based on a reticle database image produced from a design database, and a far field reticle image is simulated at an image plane of an inspection system via a physics-based process based on the near field reticle image. The deep learning process includes training a deep learning model based on minimizing differences between the far field reticle images and a plurality of corresponding training reticle images acquired by imaging a training reticle fabricated from the design database, and such training reticle images are selected for pattern variety and are defect-free.
    Type: Application
    Filed: November 27, 2018
    Publication date: July 4, 2019
    Applicant: KLA-Tencor Corporation
    Inventors: Hawren Fang, Abdurrahman Sezginer, Rui-fang Shi
  • 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: 10074036
    Abstract: Disclosed are methods and apparatus for inspecting a photolithographic reticle. Modeled images of a plurality of target features of the reticle are obtained based on a design database for fabricating the reticle. An inspection tool is used to obtain a plurality of actual images of the target features of the reticle. The modelled and actual images are binned into a plurality of bins based on image properties of the modelled and actual images, and at least some of the image properties are affected by one or more neighbor features of the target features on the reticle in a same manner. The modelled and actual images from at least one of the bins are analyzed to generate a feature characteristic uniformity map for the reticle.
    Type: Grant
    Filed: October 15, 2015
    Date of Patent: September 11, 2018
    Assignee: KLA-Tencor Corporation
    Inventors: Yanwei Liu, Hawren Fang
  • Publication number: 20160110858
    Abstract: Disclosed are methods and apparatus for inspecting a photolithographic reticle. Modeled images of a plurality of target features of the reticle are obtained based on a design database for fabricating the reticle. An inspection tool is used to obtain a plurality of actual images of the target features of the reticle. The modelled and actual images are binned into a plurality of bins based on image properties of the modelled and actual images, and at least some of the image properties are affected by one or more neighbor features of the target features on the reticle in a same manner. The modelled and actual images from at least one of the bins are analyzed to generate a feature characteristic uniformity map for the reticle.
    Type: Application
    Filed: October 15, 2015
    Publication date: April 21, 2016
    Applicant: KLA-Tencor Corporation
    Inventors: Yanwei Liu, Hawren Fang