Patents by Inventor Shohei Kamisaka

Shohei Kamisaka 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: 11751391
    Abstract: A process for building a 3-Dimensional NOR memory array avoids the challenge of etching a conductor material that is aimed at providing local word lines at a fine pitch. The process defines the local word lines between isolation shafts that may be carried out at a lower aspect ratio than would be required for etching the conductor material.
    Type: Grant
    Filed: July 21, 2021
    Date of Patent: September 5, 2023
    Assignee: SUNRISE MEMORY CORPORATION
    Inventors: Vinod Purayath, Yosuke Nosho, Shohei Kamisaka, Michiru Nakane, Eli Harari
  • Publication number: 20230247831
    Abstract: A process for building a 3-Dimensional NOR memory array avoids the challenge of etching a conductor material that is aimed at providing local word lines at a fine pitch. The process defines the local word lines between isolation shafts that may be carried out at a lower aspect ratio than would be required for etching the conductor material.
    Type: Application
    Filed: July 21, 2021
    Publication date: August 3, 2023
    Inventors: Vinod Purayath, Yosuke Nosho, Shohei Kamisaka, Michiru Nakane, Eli Harari
  • Publication number: 20220383953
    Abstract: A method for forming a three-dimensional memory structure above a semiconductor substrate includes forming two or more active stack sections, each formed on top of each other and separated by a dielectric buffer layer, where each active stack section includes multilayers separated by isolation dielectric layers and trenches with shafts filled with a sacrificial material. After the multiple active stack sections are formed, the method removes the sacrificial material in the shafts and removes portions of the dielectric buffer layer between shafts of adjacent active stack sections. The method fills the openings with a gate dielectric layer and a gate conductor. In some embodiments, the gate dielectric layer is discontinuous in the shaft over the depth of the multiple active stack sections.
    Type: Application
    Filed: April 26, 2022
    Publication date: December 1, 2022
    Inventors: Shohei Kamisaka, Vinod Purayath, Jie Zhou
  • Publication number: 20220343980
    Abstract: A process for fabricating a three-dimensional NOR memory string of storage transistors implements a channel-last fabrication process with channel replacement using silicon germanium (SiGe). In particular, the process uses silicon germanium as a sacrificial layer, to be replaced with the channel material after the charge-storage layer of the storage transistors is formed. In this manner, the channel region is prevented from experiencing excessive high-temperature processing steps, such as during the annealing of the charge-storage layer.
    Type: Application
    Filed: April 18, 2022
    Publication date: October 27, 2022
    Inventors: Shohei Kamisaka, Vinod Purayath
  • Publication number: 20220238536
    Abstract: A memory device includes source-drain structure bodies and gate structure bodies arranged along a first direction, and global word lines. The source-drain structure body includes a bit line, and first to third semiconductor layers. The first and second semiconductor layers are of first conductivity type and the first semiconductor layer is connected to the bit line. The third semiconductor layer of a second conductivity type contacts the first and second semiconductor layers. The gate structure body includes a local word line and a charge storage film. A first source-drain structure body includes a bit line forming a first reference bit line. A first global word line connects to the local word lines in the gate structure bodies formed on both sides of the first reference bit line and to the local word lines formed in alternate gate structure bodies that are formed between the remaining plurality of source-drain structure bodies.
    Type: Application
    Filed: January 14, 2022
    Publication date: July 28, 2022
    Inventors: Yosuke Nosho, Takashi Ohashi, Shohei Kamisaka, Takashi Hirotani
  • Publication number: 20220199532
    Abstract: A conductor-filled via formed between an interconnection conductor layer and a buried contact above a planar surface of a semiconductor substrate, includes: (a) a first portion that extends from the interconnection conductor layer through a first isolation layer to a step in a staircase structure formed above the buried contacts, wherein (i) the step of the staircase structure is aligned to the buried contact along a first direction substantially normal to the planar surface of the semiconductor substrate, (ii) at the top of the step, the step comprises a bit line layer, a source line layer and a second isolation layer between the bit line layer and the source line layer, and (iii) the first portion electrically contacting the layer at the top of the step; and (b) a second portion extending from a portion of the step below the layer at the top of the step to the buried contact, wherein a spacer insulator lines sidewalls of the conductor-filled via.
    Type: Application
    Filed: December 10, 2021
    Publication date: June 23, 2022
    Inventors: Shohei Kamisaka, Yosuke Nosho
  • Publication number: 20220028886
    Abstract: A process for building a 3-Dimensional NOR memory array avoids the challenge of etching a conductor material that is aimed at providing local word lines at a fine pitch. The process defines the local word lines between isolation shafts that may be carried out at a lower aspect ratio than would be required for etching the conductor material.
    Type: Application
    Filed: July 21, 2021
    Publication date: January 27, 2022
    Inventors: Vinod Purayath, Yosuke Nosho, Shohei Kamisaka, Michiru Nakane, Eli Harari