Patents by Inventor Gaurab Samanta

Gaurab Samanta 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).

  • Publication number: 20250125188
    Abstract: A method for preparing semiconductor on insulator structures comprises transferring a thin layer of silicon from a donor substrate onto a handle substrate.
    Type: Application
    Filed: December 20, 2024
    Publication date: April 17, 2025
    Inventors: Gaurab Samanta, Salvador Zepeda
  • Patent number: 12247314
    Abstract: A method for producing a silicon ingot includes withdrawing a seed crystal from a melt that includes melted silicon in a crucible that is enclosed in a vacuum chamber containing a cusped magnetic field. At least one process parameter is regulated in at least two stages, including a first stage corresponding to formation of the silicon ingot up to an intermediate ingot length, and a second stage corresponding to formation of the silicon ingot from the intermediate ingot length to the total ingot length. During the second stage process parameter regulation may include reducing a crystal rotation rate, reducing a crucible rotation rate, and/or increasing a magnetic field strength relative to the first stage.
    Type: Grant
    Filed: April 4, 2024
    Date of Patent: March 11, 2025
    Assignee: GlobalWafers Co., Ltd.
    Inventors: Gaurab Samanta, Parthiv Daggolu, Sumeet Bhagavat, Soubir Basak, Nan Zhang
  • Patent number: 12183625
    Abstract: A method for preparing semiconductor on insulator structures comprises transferring a thin layer of silicon from a donor substrate onto a handle substrate.
    Type: Grant
    Filed: August 3, 2022
    Date of Patent: December 31, 2024
    Assignee: GlobalWafers Co., Ltd.
    Inventors: Gaurab Samanta, Salvador Zepeda
  • Publication number: 20240247402
    Abstract: A method for producing a silicon ingot includes withdrawing a seed crystal from a melt that includes melted silicon in a crucible that is enclosed in a vacuum chamber containing a cusped magnetic field. At least one process parameter is regulated in at least two stages, including a first stage corresponding to formation of the silicon ingot up to an intermediate ingot length, and a second stage corresponding to formation of the silicon ingot from the intermediate ingot length to the total ingot length. During the second stage process parameter regulation may include reducing a crystal rotation rate, reducing a crucible rotation rate, and/or increasing a magnetic field strength relative to the first stage.
    Type: Application
    Filed: April 4, 2024
    Publication date: July 25, 2024
    Inventors: Gaurab Samanta, Parthiv Daggolu, Sumeet Bhagavat, Soubir Basak, Nan Zhang
  • Patent number: 12037699
    Abstract: A method for producing a silicon ingot includes withdrawing a seed crystal from a melt that includes melted silicon in a crucible that is enclosed in a vacuum chamber containing a cusped magnetic field. At least one process parameter is regulated in at least two stages, including a first stage corresponding to formation of the silicon ingot up to an intermediate ingot length, and a second stage corresponding to formation of the silicon ingot from the intermediate ingot length to the total ingot length. During the second stage process parameter regulation may include reducing a crystal rotation rate, reducing a crucible rotation rate, and/or increasing a magnetic field strength relative to the first stage.
    Type: Grant
    Filed: April 11, 2023
    Date of Patent: July 16, 2024
    Assignee: GlobalWafers Co., Ltd.
    Inventors: Gaurab Samanta, Parthiv Daggolu, Sumeet Bhagavat, Soubir Basak, Nan Zhang
  • Publication number: 20230323564
    Abstract: Nitrogen-doped CZ silicon crystal ingots and wafers sliced therefrom are disclosed that provide for post epitaxial thermally treated wafers having oxygen precipitate density and size that are substantially uniformly distributed radially and exhibit the lack of a significant edge effect. Methods for producing such CZ silicon crystal ingots are also provided by controlling the pull rate from molten silicon, the temperature gradient and the nitrogen concentration. Methods for simulating the radial bulk micro defect size distribution, radial bulk micro defect density distribution and oxygen precipitation density distribution of post epitaxial thermally treated wafers sliced from nitrogen-doped CZ silicon crystals are also provided.
    Type: Application
    Filed: June 14, 2023
    Publication date: October 12, 2023
    Inventors: Zheng Lu, Gaurab Samanta, Tse-Wei Lu, Feng-Chien Tsai
  • Patent number: 11753741
    Abstract: Nitrogen-doped CZ silicon crystal ingots and wafers sliced therefrom are disclosed that provide for post epitaxial thermally treated wafers having oxygen precipitate density and size that are substantially uniformly distributed radially and exhibit the lack of a significant edge effect. Methods for producing such CZ silicon crystal ingots are also provided by controlling the pull rate from molten silicon, the temperature gradient and the nitrogen concentration. Methods for simulating the radial bulk micro defect size distribution, radial bulk micro defect density distribution and oxygen precipitation density distribution of post epitaxial thermally treated wafers sliced from nitrogen-doped CZ silicon crystals are also provided.
    Type: Grant
    Filed: March 12, 2021
    Date of Patent: September 12, 2023
    Assignee: GlobalWafers Co., Ltd.
    Inventors: Zheng Lu, Gaurab Samanta, Tse-Wei Lu, Feng-Chien Tsai
  • Publication number: 20230250551
    Abstract: A method for producing a silicon ingot includes withdrawing a seed crystal from a melt that includes melted silicon in a crucible that is enclosed in a vacuum chamber containing a cusped magnetic field. At least one process parameter is regulated in at least two stages, including a first stage corresponding to formation of the silicon ingot up to an intermediate ingot length, and a second stage corresponding to formation of the silicon ingot from the intermediate ingot length to the total ingot length. During the second stage process parameter regulation may include reducing a crystal rotation rate, reducing a crucible rotation rate, and/or increasing a magnetic field strength relative to the first stage.
    Type: Application
    Filed: April 11, 2023
    Publication date: August 10, 2023
    Inventors: Gaurab Samanta, Parthiv Daggolu, Sumeet Bhagavat, Soubir Basak, Nan Zhang
  • Patent number: 11668020
    Abstract: A method for producing a silicon ingot includes withdrawing a seed crystal from a melt that includes melted silicon in a crucible that is enclosed in a vacuum chamber containing a cusped magnetic field. At least one process parameter is regulated in at least two stages, including a first stage corresponding to formation of the silicon ingot up to an intermediate ingot length, and a second stage corresponding to formation of the silicon ingot from the intermediate ingot length to the total ingot length. During the second stage process parameter regulation may include reducing a crystal rotation rate, reducing a crucible rotation rate, and/or increasing a magnetic field strength relative to the first stage.
    Type: Grant
    Filed: July 20, 2021
    Date of Patent: June 6, 2023
    Assignee: GlobalWafers Co., Ltd.
    Inventors: Gaurab Samanta, Parthiv Daggolu, Sumeet Bhagavat, Soubir Basak, Nan Zhang
  • Publication number: 20220375784
    Abstract: A method for preparing semiconductor on insulator structures comprises transferring a thin layer of silicon from a donor substrate onto a handle substrate.
    Type: Application
    Filed: August 3, 2022
    Publication date: November 24, 2022
    Inventors: Gaurab Samanta, Salvador Zepeda
  • Patent number: 11443978
    Abstract: A method for preparing semiconductor on insulator structures comprises transferring a thin layer of silicon from a donor substrate onto a handle substrate.
    Type: Grant
    Filed: September 18, 2020
    Date of Patent: September 13, 2022
    Assignee: GlobalWafers Co., Ltd.
    Inventors: Gaurab Samanta, Salvador Zepeda
  • Patent number: 11313049
    Abstract: A crystal pulling system for growing a monocrystalline ingot from a melt of semiconductor or solar-grade material includes a crucible for containing the melt of material, a pulling mechanism configured to pull the ingot from the melt along a pull axis, and a multi-stage heat exchanger defining a central passage for receiving the ingot as the ingot is pulled by the pulling mechanism. The heat exchanger defines a plurality of cooling zones arranged vertically along the pull axis of the crystal pulling system. The plurality of cooling zones includes two enhanced-rate cooling zones and a reduced-rate cooling zone disposed vertically between the two enhanced-rate cooling zones.
    Type: Grant
    Filed: October 19, 2016
    Date of Patent: April 26, 2022
    Assignee: GlobalWafers Co., Ltd.
    Inventors: Soubir Basak, Gaurab Samanta, Parthiv Daggolu, Benjamin Michael Meyer, William L. Luter, Jae Woo Ryu, Eric Michael Gitlin
  • Publication number: 20210348298
    Abstract: A method for producing a silicon ingot includes withdrawing a seed crystal from a melt that includes melted silicon in a crucible that is enclosed in a vacuum chamber containing a cusped magnetic field. At least one process parameter is regulated in at least two stages, including a first stage corresponding to formation of the silicon ingot up to an intermediate ingot length, and a second stage corresponding to formation of the silicon ingot from the intermediate ingot length to the total ingot length. During the second stage process parameter regulation may include reducing a crystal rotation rate, reducing a crucible rotation rate, and/or increasing a magnetic field strength relative to the first stage.
    Type: Application
    Filed: July 20, 2021
    Publication date: November 11, 2021
    Inventors: Gaurab Samanta, Parthiv Daggolu, Sumeet Bhagavat, Soubir Basak, Nan Zhang
  • Publication number: 20210340691
    Abstract: A crystal pulling system for growing a monocrystalline ingot from a melt of semiconductor or solar-grade material includes a crucible for containing the melt of material, a pulling mechanism configured to pull the ingot from the melt along a pull axis, and a multi-stage heat exchanger defining a central passage for receiving the ingot as the ingot is pulled by the pulling mechanism. The heat exchanger defines a plurality of cooling zones arranged vertically along the pull axis of the crystal pulling system. The plurality of cooling zones includes two enhanced-rate cooling zones and a reduced-rate cooling zone disposed vertically between the two enhanced-rate cooling zones.
    Type: Application
    Filed: July 16, 2021
    Publication date: November 4, 2021
    Inventors: Soubir Basak, Gaurab Samanta, Parthiv Daggolu, Benjamin Michael Meyer, William L. Luter, Jae Woo Ryu, Eric Michael Gitlin
  • Patent number: 11136691
    Abstract: A method for producing a silicon ingot includes withdrawing a seed crystal from a melt that includes melted silicon in a crucible that is enclosed in a vacuum chamber containing a cusped magnetic field. At least one process parameter is regulated in at least two stages, including a first stage corresponding to formation of the silicon ingot up to an intermediate ingot length, and a second stage corresponding to formation of the silicon ingot from the intermediate ingot length to the total ingot length. During the second stage process parameter regulation may include reducing a crystal rotation rate, reducing a crucible rotation rate, and/or increasing a magnetic field strength relative to the first stage.
    Type: Grant
    Filed: June 30, 2020
    Date of Patent: October 5, 2021
    Assignee: GlobalWafers Co., Ltd.
    Inventors: Gaurab Samanta, Parthiv Daggolu, Sumeet Bhagavat, Soubir Basak, Nan Zhang
  • Patent number: 11111602
    Abstract: Nitrogen-doped CZ silicon crystal ingots and wafers sliced therefrom are disclosed that provide for post epitaxial thermally treated wafers having oxygen precipitate density and size that are substantially uniformly distributed radially and exhibit the lack of a significant edge effect. Methods for producing such CZ silicon crystal ingots are also provided by controlling the pull rate from molten silicon, the temperature gradient and the nitrogen concentration. Methods for simulating the radial bulk micro defect size distribution, radial bulk micro defect density distribution and oxygen precipitation density distribution of post epitaxial thermally treated wafers sliced from nitrogen-doped CZ silicon crystals are also provided.
    Type: Grant
    Filed: July 29, 2015
    Date of Patent: September 7, 2021
    Assignee: GlobalWafers Co., Ltd.
    Inventors: Zheng Lu, Gaurab Samanta, Tse-Wei Lu, Feng-Chien Tsai
  • Patent number: 11072870
    Abstract: A crystal pulling system for growing a monocrystalline ingot from a melt of semiconductor or solar-grade material includes a crucible for containing the melt of material, a pulling mechanism configured to pull the ingot from the melt along a pull axis, and a multi-stage heat exchanger defining a central passage for receiving the ingot as the ingot is pulled by the pulling mechanism. The heat exchanger defines a plurality of cooling zones arranged vertically along the pull axis of the crystal pulling system. The plurality of cooling zones includes two enhanced-rate cooling zones and a reduced-rate cooling zone disposed vertically between the two enhanced-rate cooling zones.
    Type: Grant
    Filed: December 31, 2018
    Date of Patent: July 27, 2021
    Assignee: GlobalWafers Co., Ltd.
    Inventors: Soubir Basak, Gaurab Samanta, Parthiv Daggolu, Benjamin Michael Meyer, William L. Luter, Jae Woo Ryu, Eric Michael Gitlin
  • Publication number: 20210198805
    Abstract: Nitrogen-doped CZ silicon crystal ingots and wafers sliced therefrom are disclosed that provide for post epitaxial thermally treated wafers having oxygen precipitate density and size that are substantially uniformly distributed radially and exhibit the lack of a significant edge effect. Methods for producing such CZ silicon crystal ingots are also provided by controlling the pull rate from molten silicon, the temperature gradient and the nitrogen concentration. Methods for simulating the radial bulk micro defect size distribution, radial bulk micro defect density distribution and oxygen precipitation density distribution of post epitaxial thermally treated wafers sliced from nitrogen-doped CZ silicon crystals are also provided.
    Type: Application
    Filed: March 12, 2021
    Publication date: July 1, 2021
    Inventors: Zheng Lu, Gaurab Samanta, Tse-Wei Lu, Feng-Chien Tsai
  • Patent number: 10988859
    Abstract: Nitrogen-doped CZ silicon crystal ingots and wafers sliced therefrom are disclosed that provide for post epitaxial thermally treated wafers having oxygen precipitate density and size that are substantially uniformly distributed radially and exhibit the lack of a significant edge effect. Methods for producing such CZ silicon crystal ingots are also provided by controlling the pull rate from molten silicon, the temperature gradient and the nitrogen concentration. Methods for simulating the radial bulk micro defect size distribution, radial bulk micro defect density distribution and oxygen precipitation density distribution of post epitaxial thermally treated wafers sliced from nitrogen-doped CZ silicon crystals are also provided.
    Type: Grant
    Filed: May 18, 2018
    Date of Patent: April 27, 2021
    Assignee: GlobalWafers Co., Ltd.
    Inventors: Zheng Lu, Gaurab Samanta, Tse-Wei Lu, Feng-Chien Tsai
  • Publication number: 20210005508
    Abstract: A method for preparing semiconductor on insulator structures comprises transferring a thin layer of silicon from a donor substrate onto a handle substrate.
    Type: Application
    Filed: September 18, 2020
    Publication date: January 7, 2021
    Inventors: Gaurab Samanta, Salvador Zepeda