Patents by Inventor Siguang Ma

Siguang Ma 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: 10644057
    Abstract: An image sensor includes a photodiode disposed in a first semiconductor material to absorb photons incident on the image sensor and generate image charge. A floating diffusion is disposed in the first semiconductor material and positioned to receive the image charge from the photodiode, and a transfer transistor is coupled between the photodiode and the floating diffusion to transfer the image charge out of the photodiode into floating diffusion in response to a transfer signal. A source follower transistor with a gate terminal is coupled to the floating diffusion to output an amplified signal of the image charge in the floating diffusion. The gate terminal includes a second semiconductor material in contact with the floating diffusion, and a gate oxide is partially disposed between the second semiconductor material and the first semiconductor material. The second semiconductor material extends beyond the lateral bounds of the floating diffusion.
    Type: Grant
    Filed: October 2, 2018
    Date of Patent: May 5, 2020
    Assignee: OmniVision Technologies, Inc.
    Inventors: Xin Wang, Dajiang Yang, Siguang Ma, Keiji Mabuchi, Bill Phan, Duli Mao, Dyson Tai
  • Publication number: 20190109169
    Abstract: An image sensor includes a photodiode disposed in a first semiconductor material to absorb photons incident on the image sensor and generate image charge. A floating diffusion is disposed in the first semiconductor material and positioned to receive the image charge from the photodiode, and a transfer transistor is coupled between the photodiode and the floating diffusion to transfer the image charge out of the photodiode into floating diffusion in response to a transfer signal. A source follower transistor with a gate terminal is coupled to the floating diffusion to output an amplified signal of the image charge in the floating diffusion. The gate terminal includes a second semiconductor material in contact with the floating diffusion, and a gate oxide is partially disposed between the second semiconductor material and the first semiconductor material. The second semiconductor material extends beyond the lateral bounds of the floating diffusion.
    Type: Application
    Filed: October 2, 2018
    Publication date: April 11, 2019
    Inventors: Xin Wang, Dajiang Yang, Siguang Ma, Keiji Mabuchi, Bill Phan, Duli Mao, Dyson Tai
  • Patent number: 10243015
    Abstract: A method for fabricating a photosensor array integrated circuit includes forming an isolation trench by a method comprising depositing a hard mask layer on a [110]-oriented single-crystal silicon substrate wafer, depositing, exposing, and developing a photoresist on the hard mask layer to define photoresist openings of locations for the trenches, dry plasma etching through the photoresist openings to form openings in the hard mask layer of locations for the trenches, and performing an anisotropic wet etch through the openings in the hard mask layer. In particular embodiments, the trenches are lined with P-type silicon, a silicon dioxide dielectric, and an additional oxide layer before being filled with tungsten.
    Type: Grant
    Filed: January 16, 2018
    Date of Patent: March 26, 2019
    Assignee: OmniVision Technologies, Inc.
    Inventors: Xin Wang, Dajiang Yang, Siguang Ma, Duli Mao, Dyson H. Tai
  • Patent number: 10128299
    Abstract: An image sensor includes a photodiode disposed in a first semiconductor material to absorb photons incident on the image sensor and generate image charge. A floating diffusion is disposed in the first semiconductor material and positioned to receive the image charge from the photodiode, and a transfer transistor is coupled between the photodiode and the floating diffusion to transfer the image charge out of the photodiode into floating diffusion in response to a transfer signal. A source follower transistor with a gate terminal is coupled to the floating diffusion to output an amplified signal of the image charge in the floating diffusion. The gate terminal includes a second semiconductor material in contact with the floating diffusion, and a gate oxide is partially disposed between the second semiconductor material and the first semiconductor material. The second semiconductor material extends beyond the lateral bounds of the floating diffusion.
    Type: Grant
    Filed: October 10, 2017
    Date of Patent: November 13, 2018
    Assignee: OmniVision Technologies, Inc.
    Inventors: Xin Wang, Dajiang Yang, Siguang Ma, Keiji Mabuchi, Bill Phan, Duli Mao, Dyson Tai
  • Patent number: 10044960
    Abstract: An image sensor for detecting light-emitting diode (LED) without flickering includes a pixel array with pixels. Each pixel including subpixels including a first and a second subpixel, dual floating diffusion (DFD) transistor, and a capacitor coupled to the DFD transistor. First subpixel includes a first photosensitive element to acquire a first image charge, and a first transfer gate transistor to selectively transfer the first image charge from the first photosensitive element to a first floating diffusion (FD) node. Second subpixel includes a second photosensitive element to acquire a second image charge, and a second transfer gate transistor to selectively transfer the second image charge from the second photosensitive element to a second FD node. DFD transistor coupled to the first and the second FD nodes. Other embodiments are also described.
    Type: Grant
    Filed: May 25, 2016
    Date of Patent: August 7, 2018
    Assignee: OmniVision Technologies, Inc.
    Inventors: Duli Mao, Trygve Willassen, Johannes Solhusvik, Keiji Mabuchi, Gang Chen, Sohei Manabe, Dyson H. Tai, Bill Phan, Oray Orkun Cellek, Zhiqiang Lin, Siguang Ma, Dajiang Yang, Boyd Albert Fowler
  • Publication number: 20170347047
    Abstract: An image sensor for detecting light-emitting diode (LED) without flickering includes a pixel array with pixels. Each pixel including subpixels including a first and a second subpixel, dual floating diffusion (DFD) transistor, and a capacitor coupled to the DFD transistor. First subpixel includes a first photosensitive element to acquire a first image charge, and a first transfer gate transistor to selectively transfer the first image charge from the first photosensitive element to a first floating diffusion (FD) node. Second subpixel includes a second photosensitive element to acquire a second image charge, and a second transfer gate transistor to selectively transfer the second image charge from the second photosensitive element to a second FD node. DFD transistor coupled to the first and the second FD nodes. Other embodiments are also described.
    Type: Application
    Filed: May 25, 2016
    Publication date: November 30, 2017
    Inventors: Duli Mao, Trygve Willassen, Johannes Solhusvik, Keiji Mabuchi, Gang Chen, Sohei Manabe, Dyson H. Tai, Bill Phan, Oray Orkun Cellek, Zhiqiang Lin, Siguang Ma, Dajiang Yang, Boyd Albert Fowler
  • Publication number: 20090001352
    Abstract: Provided is a non-volatile memory device that can be highly integrated and may have a high reliability. Some embodiments of the non-volatile memory device include a first doping layer having a first conductivity on a substrate, a semiconductor pillar extending from the first doping layer on the substrate in an upward direction and having second conductivity opposite to the first conductivity, and a control gate electrode surrounding a sidewall of the semiconductor pillar. Embodiments of the non-volatile memory device may include a charge storage layer interposed between the semiconductor pillar and the control gate electrode and a second doping layer of the first conductivity that is disposed on the semiconductor pillar and is electrically connected to the semiconductor pillar.
    Type: Application
    Filed: March 27, 2008
    Publication date: January 1, 2009
    Inventors: Jeong-hee Han, Ji-Young Kim, Chung-woo Kim, Kang Long Wang, Siguang Ma
  • Publication number: 20070235076
    Abstract: The present invention relates to embodiments of TPV cell structures based on carbon nanotube and nanowire materials. One embodiment according to the present invention is a p-n junction carbon nanotube/nanowire TPV cell, which is formed by p-n junction wires. A second embodiment according to the present invention is a carbon nanotube/nanowire used as a p-type (or n-type), and using bulk material as the other complementary type to a form p-n junction TPV cell. A third embodiment according to the present invention uses a controllable Schottky barrier height between a one-dimensional nanowire and a metal contact to form the built-in potential of the TPV cells.
    Type: Application
    Filed: November 20, 2006
    Publication date: October 11, 2007
    Inventors: Fei Liu, Siguang Ma, Kang Wang