Patents by Inventor Wenfei Gu

Wenfei Gu 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: 11727556
    Abstract: Methods and systems for detecting defects on a mask are provided. One method includes generating a database reference image for a multi-die mask by simulation and detecting first defects on the mask by comparing the database reference image to images of the mask generated by an imaging subsystem for a first of the multiple dies. The method also includes generating a die reference image for the first of the multiple dies by applying one or more parameters of the imaging subsystem learned by generating the database reference image to the images generated by the imaging subsystem of one or more of the multiple dies other than the first multiple die. In addition, the method includes detecting second defects on the mask by comparing the die reference image to the images of the mask generated by the imaging subsystem for the first of the multiple dies.
    Type: Grant
    Filed: September 29, 2021
    Date of Patent: August 15, 2023
    Assignee: KLA Corp.
    Inventors: Wenfei Gu, Pei-Chun Chiang, Weston Sousa
  • Publication number: 20230098730
    Abstract: Methods and systems for detecting defects on a mask are provided. One method includes generating a database reference image for a multi-die mask by simulation and detecting first defects on the mask by comparing the database reference image to images of the mask generated by an imaging subsystem for a first of the multiple dies. The method also includes generating a die reference image for the first of the multiple dies by applying one or more parameters of the imaging subsystem learned by generating the database reference image to the images generated by the imaging subsystem of one or more of the multiple dies other than the first multiple die. In addition, the method includes detecting second defects on the mask by comparing the die reference image to the images of the mask generated by the imaging subsystem for the first of the multiple dies.
    Type: Application
    Filed: September 29, 2021
    Publication date: March 30, 2023
    Inventors: Wenfei Gu, Pei-Chun Chiang, Weston Sousa
  • Patent number: 10140698
    Abstract: Disclosed are methods and apparatus for providing feature classification for inspection of a photolithographic mask. A design database for fabrication of a mask includes polygons that are each defined by a set of vertices. Any of the polygons that abut each other are grouped together. Any grouped polygons are healed so as to eliminate interior edges of each set of grouped polygons to obtain a polygon corresponding to a covering region of such set of grouped polygons. Geometric constraints that specify requirements for detecting a plurality of feature classes are provided and used for detecting a plurality of feature classes in the polygons of the design database. The detected features classes are used to detect defects in the mask.
    Type: Grant
    Filed: August 8, 2016
    Date of Patent: November 27, 2018
    Assignee: KLA-Tencor Corporation
    Inventors: Yin Xu, Wenfei Gu, Rui-fang Shi
  • Publication number: 20170046471
    Abstract: Disclosed are methods and apparatus for providing feature classification for inspection of a photolithographic mask. A design database for fabrication of a mask includes polygons that are each defined by a set of vertices. Any of the polygons that abut each other are grouped together. Any grouped polygons are healed so as to eliminate interior edges of each set of grouped polygons to obtain a polygon corresponding to a covering region of such set of grouped polygons. Geometric constraints that specify requirements for detecting a plurality of feature classes are provided and used for detecting a plurality of feature classes in the polygons of the design database. The detected features classes are used to detect defects in the mask.
    Type: Application
    Filed: August 8, 2016
    Publication date: February 16, 2017
    Applicant: KLA-Tencor Corporation
    Inventors: Yin Xu, Wenfei Gu, Rui-fang Shi