Patents by Inventor Hui Zang

Hui Zang 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: 11677011
    Abstract: A method of fabricating transistors with a vertical gate in trenches includes lithographing to form wide trenches; forming dielectric in the trenches and filling the trenches with flowable material; and lithography to form narrow trenches within the wide trenches thereby exposing well or substrate before epitaxially growing semiconductor strips atop substrate exposed by the narrow trenches; removing the flowable material; growing gate oxide on the semiconductor strip; forming gate conductor over the gate oxide and into gaps between the epitaxially-grown semiconductor strips and the dielectric; masking and etching the gate conductor; and implanting source and drain regions. The transistors formed have semiconductor strips extending from a source region to a drain region, the semiconductor strips within trenches, the trench walls insulated with a dielectric, a gate oxide formed on both vertical walls of the semiconductor strip; and gate material between the dielectric and gate oxide.
    Type: Grant
    Filed: December 18, 2020
    Date of Patent: June 13, 2023
    Assignee: OmniVision Technologies, Inc.
    Inventors: Yuanliang Liu, Hui Zang
  • Patent number: 11670648
    Abstract: A flicker-mitigating pixel-array substrate includes a semiconductor substrate and a metal layer. The semiconductor substrate includes a small-photodiode region. A back surface of the semiconductor substrate forms a trench surrounding the small-photodiode region in a cross-sectional plane parallel to a first back-surface region of the back surface above the small-photodiode region. The metal layer covers the first back-surface region, at least partially fills the trench, and surrounds the small-photodiode region in the cross-sectional plane. A method for fabricating a flicker-mitigating pixel-array substrate includes forming, on a back surface of a semiconductor substrate, a trench that surrounds a small-photodiode region of the semiconductor substrate in a cross-sectional plane parallel to a first back-surface region of the back surface above the small-photodiode region. The method also includes forming a metal layer on the first back-surface region and in the trench.
    Type: Grant
    Filed: December 10, 2020
    Date of Patent: June 6, 2023
    Assignee: OmniVision Technologies Inc.
    Inventors: Yuanliang Liu, Hui Zang
  • Publication number: 20230154960
    Abstract: A dark-current-inhibiting image sensor includes a semiconductor substrate, a thin and a thin junction. The semiconductor substrate includes a front surface, a back surface opposite the front surface, a photodiode, and a concave surface between the front surface and the back surface. The concave surface extends from the back surface toward the front surface, and defines a trench that surrounds the photodiode in a cross-sectional plane parallel to the back surface. The thin junction extends from the concave surface into the semiconductor substrate, and is a region of the semiconductor substrate. The semiconductor substrate includes a first substrate region, located between the thin junction and the photodiode, that has a first conductive type. The photodiode and the thin junction have a second conductive type opposite the first conductive type.
    Type: Application
    Filed: November 18, 2021
    Publication date: May 18, 2023
    Inventors: Yifei DU, Zhiqiang LIN, Hui ZANG, Seong Yeol MUN
  • Patent number: 11621336
    Abstract: Transistors include a pyramid-shaped gate trench defined by a triangular shape or a trapezoidal shape in a channel width plane and a trapezoidal shape in a channel length plane. Side wall portions of the pyramid-shaped gate trench form a channel having a triangular shape or a trapezoidal shape in the channel width plane. Advantageously, such transistors increase transconductance without increasing pixel width. Devices, image sensors, and pixels incorporating such transistors are also provided, in addition to methods of manufacturing the same.
    Type: Grant
    Filed: May 20, 2021
    Date of Patent: April 4, 2023
    Assignee: OMNIVISION TECHNOLOGIES, INC.
    Inventors: Hui Zang, Gang Chen
  • Patent number: 11610965
    Abstract: A gate cut isolation including an air gap and an IC including the same are disclosed. A method of forming the gate cut isolation may include forming an opening in a dummy gate that extends over a plurality of spaced active regions, the opening positioned between and spaced from a pair of active regions. The opening is filled with a fill material, and the dummy gate is removed. A metal gate is formed in a space vacated by the dummy gate on each side of the fill material, and the fill material is removed to form a preliminary gate cut opening. A liner is deposited in the preliminary gate cut opening, creating a gate cut isolation opening, which is then sealed by depositing a sealing layer. The sealing layer closes an upper end of the gate cut isolation opening and forms the gate cut isolation including an air gap.
    Type: Grant
    Filed: February 25, 2021
    Date of Patent: March 21, 2023
    Assignee: GLOBALFOUNDRIES U.S. INC.
    Inventors: Hong Yu, Hui Zang, Jiehui Shu
  • Publication number: 20230067685
    Abstract: A pixel of an image sensor includes a semiconductor substrate having a front surface and a back surface opposing the front surface, a photodiode and floating diffusion (FD) region formed in the substrate along a first pixel axis parallel to the front surface and a transfer gate formed in the front surface of the substrate between the photodiode and the FD region. The transfer gate includes a planar gate on the front surface of the substrate, a vertical transfer gate extending into the substrate from the planar gate, the vertical transfer gate further including a trench and a layer of doped semiconductor material epitaxially grown on the sides and bottom of the trench. The semiconductor substrate and the epitaxial layer comprise a first conductive type, and the photodiode and the FD region comprise a second conductive type. An image sensor and method of forming the vertical transfer gate are disclosed.
    Type: Application
    Filed: August 25, 2021
    Publication date: March 2, 2023
    Inventors: Hui ZANG, Gang CHEN
  • Publication number: 20230053960
    Abstract: A method for forming a contact pad of a semiconductor device is disclosed. The method includes providing a semiconductor substrate including a first side and a second side. The semiconductor device includes a shallow trench isolation structure, disposed between the first side and the second side, and an intermetal dielectric stack coupled to the second side. The intermetal dielectric stack includes a first metal interconnect. The method further includes etching a first trench into the semiconductor substrate, depositing a dielectric material into the first trench to form a dielectric spacer extending along side walls of the first trench, etching a second trench aligned with the first trench, and depositing a metal material into the second trench to form the contact pad that contacts the first metal interconnect.
    Type: Application
    Filed: August 20, 2021
    Publication date: February 23, 2023
    Inventor: Hui Zang
  • Patent number: 11588033
    Abstract: Transistors having nonplanar electron channels in the channel width plane have one or more features that cause the different parts of the nonplanar electron channel to turn on at substantially the same threshold voltage. Advantageously, such transistors have substantially uniform threshold voltage across the nonplanar electron channel. Devices, image sensors, and pixels incorporating such transistors are also provided, in addition to methods of manufacturing the same.
    Type: Grant
    Filed: May 20, 2021
    Date of Patent: February 21, 2023
    Assignee: OMNIVISION TECHNOLOGIES, INC.
    Inventors: Hui Zang, Gang Chen
  • Patent number: 11574947
    Abstract: A photodiode array has buried photodiodes and vertical selection transistors. Trenches are lined with gate oxide and metallic plugs of first material lie within the trenches. Gate contacts of second material contact the metallic plugs, with photodiode diffusion regions adjacent the trenches as sources of vertical transistors, the metallic plugs form gates of the vertical transistors, and buried photodiode regions form sources of the vertical transistors. In embodiments, the first conductive material is tungsten, titanium nitride, titanium carbide, or aluminum and the second conductive material is polysilicon. The array is formed by trenching, growing gate oxide, and depositing first material in the trenches. The first material is etched to define metallic plugs, the second material is deposited onto the metallic plugs then masked and etched; and drain regions implanted. Etching the second material is performed by a reactive ion etch that stops upon reaching the metallic plugs.
    Type: Grant
    Filed: August 18, 2020
    Date of Patent: February 7, 2023
    Assignee: OmniVision Technologies, Inc.
    Inventors: Hui Zang, Gang Chen
  • Patent number: 11569356
    Abstract: The present disclosure relates to semiconductor structures and, more particularly, to a scaled gate contact and source/drain cap and methods of manufacture. The structure includes: a gate structure comprising an active region; source and drain contacts adjacent to the gate structure; a capping material over the source and drain contacts; a gate contact formed directly above the active region of the gate structure and over the capping material; a U-shape dielectric material around the gate contact, above the source and drain contacts; and a contact in direct electrical contact to the source and drain contacts.
    Type: Grant
    Filed: November 13, 2020
    Date of Patent: January 31, 2023
    Assignee: GLOBALFOUNDRIES U.S. INC.
    Inventors: Hui Zang, Ruilong Xie, Jae Gon Lee
  • Publication number: 20220416054
    Abstract: One illustrative integrated circuit (IC) product disclosed herein includes a first conductive source/drain contact structure of a first transistor with an insulating source/drain cap positioned above at least a portion of an upper surface of the first conductive source/drain contact structure and a gate-to-source/drain (GSD) contact structure that is conductively coupled to the first conductive source/drain contact structure and a first gate structure of a second transistor. In this example, the product also includes a gate contact structure that is conductively coupled to a second gate structure of a third transistor, wherein an upper surface of each of the GSD contact structure and the gate contact structure is positioned at a first level that is at a level that is above a level of an upper surface of the insulating source/drain cap.
    Type: Application
    Filed: September 2, 2022
    Publication date: December 29, 2022
    Inventors: Ruilong Xie, Youngtag Woo, Daniel Chanemougame, Bipul C. Paul, Lars W. Liebmann, Heimanu Niebojewski, Xuelian Zhu, Lei Sun, Hui Zang
  • Patent number: 11538836
    Abstract: A pixel cell includes a photodiode disposed proximate to a front side of a semiconductor layer to generate image charge in response to incident light directed through a backside of the semiconductor layer. A cell deep trench isolation (CDTI) structure is disposed along an optical path of the incident light to the photodiode and proximate to the backside of the semiconductor layer. The CDTI structure includes a plurality of portions arranged in the semiconductor layer. Each of the plurality of portions extends a respective depth from the backside towards the front side of the semiconductor layer. The respective depth of each of the plurality of portions is different than a respective depth of a neighboring one of the plurality of portions. Each of the plurality of portions is laterally separated and spaced apart from said neighboring one of the plurality of portions in the semiconductor layer.
    Type: Grant
    Filed: August 13, 2020
    Date of Patent: December 27, 2022
    Assignee: OmniVision Technologies, Inc.
    Inventors: Hui Zang, Gang Chen, Chao Niu, Zhiqiang Lin
  • Patent number: 11522005
    Abstract: Methods of forming trench structures of different depths in a semiconductor substrate are provided. A first mask forming a first opening and a second opening is provided on the semiconductor substrate. The semiconductor substrate is etched through the first and second openings, thereby forming a first trench and a second trench. Trench structure material is deposited in the first and second trenches, thereby forming first and second trench structures. A second mask is provided on the first mask, wherein the second mask covers the first opening and has a third opening superimposed over the second opening of the first mask. The second trench structure is etched through the second opening of the first mask and through the third opening of the second mask.
    Type: Grant
    Filed: August 18, 2021
    Date of Patent: December 6, 2022
    Assignee: OMNIVISION TECHNOLOGIES, INC.
    Inventor: Hui Zang
  • Publication number: 20220376069
    Abstract: Transistors having nonplanar electron channels in the channel width plane have one or more features that cause the different parts of the nonplanar electron channel to turn on at substantially the same threshold voltage. Advantageously, such transistors have substantially uniform threshold voltage across the nonplanar electron channel. Devices, image sensors, and pixels incorporating such transistors are also provided, in addition to methods of manufacturing the same.
    Type: Application
    Filed: May 20, 2021
    Publication date: November 24, 2022
    Applicant: OMNIVISION TECHNOLOGIES, INC.
    Inventors: Hui Zang, Gang Chen
  • Publication number: 20220375788
    Abstract: A semiconductor device includes one or more fins extending from a substrate, the one or more fins having source/drain epitaxial grown material (S/D epitaxy) thereon that merges one or more fins, a gate formed over the one or more fins, the gate including high k metal gate disposed between gate spacers and a metal liner over the S/D epitaxy and sides of the gate spacers. The gate includes a self-aligned contact cap over the HKMG and the metal liner.
    Type: Application
    Filed: August 4, 2022
    Publication date: November 24, 2022
    Inventors: Andrew Greene, Ruilong Xie, Laertis Economikos, Veeraraghavan S. Basker, Chanro Park, Hui Zang
  • Publication number: 20220375977
    Abstract: Transistors having nonplanar electron channels in the channel width plane have one or more features that cause the different parts of the nonplanar electron channel to turn on at substantially the same threshold voltage. Advantageously, such transistors have substantially uniform threshold voltage across the nonplanar electron channel. Devices, image sensors, and pixels incorporating such transistors are also provided, in addition to methods of manufacturing the same.
    Type: Application
    Filed: May 20, 2021
    Publication date: November 24, 2022
    Applicant: OMNIVISION TECHNOLOGIES, INC.
    Inventors: Hui Zang, Gang Chen
  • Publication number: 20220376068
    Abstract: Transistors include a pyramid-shaped gate trench defined by a triangular shape or a trapezoidal shape in a channel width plane and a trapezoidal shape in a channel length plane. Side wall portions of the pyramid-shaped gate trench form a channel having a triangular shape or a trapezoidal shape in the channel width plane. Advantageously, such transistors increase transconductance without increasing pixel width. Devices, image sensors, and pixels incorporating such transistors are also provided, in addition to methods of manufacturing the same.
    Type: Application
    Filed: May 20, 2021
    Publication date: November 24, 2022
    Applicant: OMNIVISION TECHNOLOGIES, INC.
    Inventors: Hui Zang, Gang Chen
  • Publication number: 20220359581
    Abstract: Process to release Silicon stress in forming CMOS image sensor. In one embodiment, a method for manufacturing an image sensor includes providing a first wafer that is a semiconductor substrate, where the first wafer has a first side and a second side opposite from the first side. The method also includes attaching a second wafer to the second side of the first wafer. The method further includes forming isolation structures in the second wafer by etching. The isolation structures are bounded by the second side of the first wafer. The method also includes growing an epitaxial layer between individual isolation structures.
    Type: Application
    Filed: May 4, 2021
    Publication date: November 10, 2022
    Inventors: Yuanliang Liu, Hui Zang
  • Publication number: 20220352220
    Abstract: An image sensor comprises a first photodiode region and circuitry. The first photodiode region is disposed within a semiconductor substrate proximate to a first side of the semiconductor substrate to form a first pixel. The first photodiode region includes a first segment coupled to a second segment. The circuitry includes at least a first electrode associated with a first transistor. The first electrode is disposed, at least in part, between the first segment and the second segment of the first photodiode region such that the circuity is at least partially surrounded by the first photodiode region when viewed from the first side of the semiconductor substrate.
    Type: Application
    Filed: April 28, 2021
    Publication date: November 3, 2022
    Inventors: Hui Zang, Yuanliang Liu, Keiji Mabuchi, Gang Chen, Bill Phan, Duli Mao, Takeshi Takeda
  • Publication number: 20220344212
    Abstract: The present disclosure relates to semiconductor structures and, more particularly, to a single diffusion cut for gate structures and methods of manufacture. The structure includes: a plurality of fin structures; a plurality of gate structures extending over the plurality of fin structures; a plurality of diffusion regions adjacent to the each of the plurality of gate structures; a single diffusion break between the diffusion regions of the adjacent gate structures; and a liner separating the single diffusion break from the diffusion regions.
    Type: Application
    Filed: July 11, 2022
    Publication date: October 27, 2022
    Inventors: Hui ZANG, Ruilong XIE