Patents by Inventor Sonam SHERPA

Sonam SHERPA 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).

  • Method for atomic layer etching
    Patent number: 9881807
    Abstract: A method of etching a layer on a substrate includes disposing a substrate in a plasma processing system configured to facilitate an etching process, performing an atomic layer etching process cycle to etch a monolayer of an exposed surface of the substrate, and repeating the atomic layer etching process cycle until a target depth is reached. Each process cycle etches the monolayer from the exposed surface.
    Type: Grant
    Filed: March 29, 2016
    Date of Patent: January 30, 2018
    Assignee: Tokyo Electron Limited
    Inventors: Alok Ranjan, Sonam Sherpa, Mingmei Wang
  • Method and apparatus for ESC charge control for wafer clamping
    Patent number: 9530626
    Abstract: A plasma processing method and apparatus are provided in which current spikes associated with application of a voltage to an electrostatic chuck (ESC) are minimized or reduced when the processing plasma is present. According to an example, the voltage is applied to the ESC after the processing plasma is struck, however the voltage is ramped or increased in a step-wise manner to achieve the desired final ESC voltage. In an alternate embodiment, the ESC voltage is at least partially applied before striking of the plasma for processing the wafer. By reducing current spikes associated with application of the voltage to the ESC during the presence of the processing plasma, transfer or deposition of particles on the wafer can be reduced.
    Type: Grant
    Filed: July 23, 2015
    Date of Patent: December 27, 2016
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Jason Marion, Sonam Sherpa, Sergey A. Voronin, Alok Ranjan, Yoshio Ishikawa, Takashi Enomoto
  • METHOD FOR ATOMIC LAYER ETCHING
    Publication number: 20160293432
    Abstract: A method of etching a layer on a substrate includes disposing a substrate in a plasma processing system configured to facilitate an etching process, performing an atomic layer etching process cycle to etch a monolayer of an exposed surface of the substrate, and repeating the atomic layer etching process cycle until a target depth is reached. Each process cycle etches the monolayer from the exposed surface.
    Type: Application
    Filed: March 29, 2016
    Publication date: October 6, 2016
    Inventors: Alok Ranjan, Sonam Sherpa, Mingmei Wang
  • METHOD AND APPARATUS FOR ESC CHARGE CONTROL FOR WAFER CLAMPING
    Publication number: 20160027620
    Abstract: A plasma processing method and apparatus are provided in which current spikes associated with application of a voltage to an electrostatic chuck (ESC) are minimized or reduced when the processing plasma is present. According to an example, the voltage is applied to the ESC after the processing plasma is struck, however the voltage is ramped or increased in a step-wise manner to achieve the desired final ESC voltage. In an alternate embodiment, the ESC voltage is at least partially applied before striking of the plasma for processing the wafer. By reducing current spikes associated with application of the voltage to the ESC during the presence of the processing plasma, transfer or deposition of particles on the wafer can be reduced.
    Type: Application
    Filed: July 23, 2015
    Publication date: January 28, 2016
    Applicant: TOKYO ELECTRON LIMITED
    Inventors: Jason MARION, Sonam SHERPA, Sergey A. VORONIN, Alok RANJAN, Yoshio ISHIKAWA, Takashi ENOMOTO