Patents by Inventor Chengxiang Ji

Chengxiang Ji 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: 9653266
    Abstract: An apparatus for generating plasma includes a plasma discharge tube and a conductive coil helically wound around an outer surface of the plasma discharge tube. A waveguide is coupled to a microwave cavity surrounding the plasma discharge tube to guide the microwave energy into the plasma discharge tube such that the plasma is generated in the plasma discharge tube. The waveguide is positioned such that an electric field of the microwave energy is oriented at a predetermined angle with respect to the longitudinal axis of the plasma discharge tube. A resulting induced electric current in the conductive coil affects power absorption in the plasma discharge tube, the predetermined angle being selectable such that power absorption in the plasma discharge tube is according to a predetermined profile with respect to the longitudinal axis of the plasma discharge tube.
    Type: Grant
    Filed: March 12, 2015
    Date of Patent: May 16, 2017
    Assignee: MKS Instruments, Inc.
    Inventors: Xing Chen, Chengxiang Ji, Erin Madden, Ilya Pokidov, Kevin W. Wenzel
  • Publication number: 20150318148
    Abstract: An apparatus for generating plasma includes a plasma discharge tube and a conductive coil helically wound around an outer surface of the plasma discharge tube. A waveguide is coupled to a microwave cavity surrounding the plasma discharge tube to guide the microwave energy into the plasma discharge tube such that the plasma is generated in the plasma discharge tube. The waveguide is positioned such that an electric field of the microwave energy is oriented at a predetermined angle with respect to the longitudinal axis of the plasma discharge tube. A resulting induced electric current in the conductive coil affects power absorption in the plasma discharge tube, the predetermined angle being selectable such that power absorption in the plasma discharge tube is according to a predetermined profile with respect to the longitudinal axis of the plasma discharge tube.
    Type: Application
    Filed: March 12, 2015
    Publication date: November 5, 2015
    Applicant: MKS INSTRUMENTS, INC.
    Inventors: Xing Chen, Chengxiang Ji, Erin Madden, IIya Pokidov, Kevin W. Wenzel
  • Publication number: 20150279626
    Abstract: An apparatus for generating plasma includes a plasma discharge tube and a conductive coil helically wound around an outer surface of the plasma discharge tube. A waveguide is coupled to a microwave cavity surrounding the plasma discharge tube to guide the microwave energy into the plasma discharge tube such that the plasma is generated in the plasma discharge tube. The waveguide is positioned such that an electric field of the microwave energy is oriented at a predetermined angle with respect to the longitudinal axis of the plasma discharge tube. A resulting induced electric current in the conductive coil affects power absorption in the plasma discharge tube, the predetermined angle being selectable such that power absorption in the plasma discharge tube is according to a predetermined profile with respect to the longitudinal axis of the plasma discharge tube.
    Type: Application
    Filed: March 27, 2014
    Publication date: October 1, 2015
    Applicant: MKS INSTRUMENTS, INC.
    Inventors: Xing Chen, Chengxiang Ji, Erin Madden, Ilya Pokidov, Kevin W. Wenzel
  • Patent number: 8888982
    Abstract: A method for creating an oxide layer having a reduced copper concentration over a surface of an object comprising aluminum and copper for use in a semiconductor processing system. The oxide layer produced using a plasma electrolytic oxidation process has a reduced copper peak concentration, which decreases a risk of copper contamination, and includes magnesium oxides that can be converted to magnesium halide upon exposure to an excited halogen-comprising gas or halogen-comprising plasma to increase the erosion/corrosion resistance of the oxide layer.
    Type: Grant
    Filed: June 4, 2010
    Date of Patent: November 18, 2014
    Assignee: MKS Instruments Inc.
    Inventors: Xing Chen, Chengxiang Ji, Chiu-Ying Tai
  • Publication number: 20130146225
    Abstract: A plasma chamber for use with a reactive gas source that includes a first conduit comprising a wall, an inlet, an outlet, an inner and outer surface, and a plurality of openings through the wall, the inlet receives a first gas for generating a reactive gas in the first conduit with a plasma formed in the first conduit. The plasma chamber also includes a second conduit that includes a wall, an inlet, and an inner surface. The first conduit is disposed in the second conduit defining a channel between the outer surface of the first conduit and the inner surface of the second conduit. A second gas provided to the inlet of the second conduit flows along the channel and through the plurality of openings of the wall of the first conduit into the first conduit to surround the reactive gas and plasma in the first conduit.
    Type: Application
    Filed: December 8, 2011
    Publication date: June 13, 2013
    Applicant: MKS INSTRUMENTS, INC.
    Inventors: Xing Chen, Youfan Gu, Chengxiang Ji, Paul Ashby Loomis, Ilya Pokidov, Kevin Wayne Wenzel
  • Publication number: 20110297319
    Abstract: A method for creating an oxide layer having a reduced copper concentration over a surface of an object comprising aluminum and copper for use in a semiconductor processing system. The oxide layer produced using a plasma electrolytic oxidation process has a reduced copper peak concentration, which decreases a risk of copper contamination, and includes magnesium oxides that can be converted to magnesium halide upon exposure to an excited halogen-comprising gas or halogen-comprising plasma to increase the erosion/corrosion resistance of the oxide layer.
    Type: Application
    Filed: June 4, 2010
    Publication date: December 8, 2011
    Applicant: MKS Instruments, Inc.
    Inventors: Xing Chen, Chengxiang Ji, Chiu-Ying Tai