Patents by Inventor Nobuyuki Fujimura

Nobuyuki Fujimura 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: 20240147723
    Abstract: A memory device includes source-level material layers including a source contact layer, an alternating stack of insulating layers and electrically conductive layers located over the source-level material layers, a memory opening vertically extending through the alternating stack and the source contact layer, and a memory opening fill structure located in the memory opening and including a vertical semiconductor channel including an intrinsic or first conductivity type semiconductor material, a memory film surrounding the vertical semiconductor channel, and a conical source pedestal in contact with the source contact layer and in contact with a bottom surface of the vertical semiconductor channel, such that at least portion of the conical source pedestal includes a second conductivity type semiconductor material.
    Type: Application
    Filed: July 12, 2023
    Publication date: May 2, 2024
    Inventors: Motoo OHAGA, Tadashi NAKAMURA, Takashi YUDA, Nobuyuki FUJIMURA, Hiroyuki OGAWA
  • Publication number: 20240015963
    Abstract: A semiconductor structure includes an alternating stack of insulating layers and electrically conductive layers, where the electrically conductive layers include word line electrically conductive layers and a first select-level electrically conductive layer, a memory opening vertically extending through the alternating stack, and a memory opening fill structure located in the memory opening and including a memory film and a vertical semiconductor channel. A vertical cross-sectional profile of an outer sidewall of the vertical semiconductor channel is straight throughout the word line electrically conductive layers and contains a lateral protrusion at a level of the first select-level electrically conductive layer.
    Type: Application
    Filed: July 7, 2022
    Publication date: January 11, 2024
    Inventors: Tadashi NAKAMURA, Nobuyuki FUJIMURA
  • Publication number: 20230345727
    Abstract: A method of forming a memory device includes forming an insulating layer and a composite sacrificial material layer having a vertical compositional change that is stepwise or gradual such that a bottommost portion and a topmost portion of the composite sacrificial material layer a different etch rate in an isotropic etchant than the middle portion, forming a memory opening, laterally recessing the composite sacrificial material layers selective to the insulating layers around the memory opening by introducing the isotropic etchant into the memory opening to form lateral recesses in the composite sacrificial material layers, forming a memory opening fill structure within the memory opening, where the memory opening fill structure includes a vertical stack of memory elements that are formed in the lateral recesses, a dielectric material liner, and a vertical semiconductor channel, and replacing the composite sacrificial material layers with electrically conductive layers.
    Type: Application
    Filed: July 5, 2023
    Publication date: October 26, 2023
    Inventors: Nobuyuki FUJIMURA, Satoshi SHIMIZU, Takumi MORIYAMA, Senaka KANAKAMEDALA
  • Publication number: 20230328981
    Abstract: A memory device includes a first alternating stack of first insulating layers and first electrically conductive layers located over a substrate, a memory opening vertically extending through the first alternating stack and having a tapered sidewall surface at a level of one of the first electrically conductive layers, and a memory opening fill structure located in the memory opening and comprising a vertical stack of memory elements and a vertical semiconductor channel. One of the first electrically conductive layers includes a taper-containing electrically conductive layer that is located at a level of the lateral protrusion of the memory opening and has a contoured sidewall having a tapered sidewall segment that is parallel to the tapered sidewall surface of the lateral protrusion.
    Type: Application
    Filed: April 7, 2022
    Publication date: October 12, 2023
    Inventors: Nobuyuki Fujimura, Shunsuke Takuma, Takashi Kudo, Satoshi Shimizu, Zhixin Cui
  • Publication number: 20230328984
    Abstract: A memory device includes at least one alternating stack of insulating layers and electrically conductive layers, a memory opening vertically extending through the at least one alternating stack, and a memory opening fill structure located in the memory opening and containing a vertical stack of memory elements and a vertical semiconductor channel. The memory opening fill structure includes a lateral protrusion having a tapered sidewall surface; and one of the electrically conductive layers is a taper-containing electrically conductive layer that is located at a level of the lateral protrusion of the memory opening fill structure.
    Type: Application
    Filed: December 1, 2022
    Publication date: October 12, 2023
    Inventors: Nobuyuki FUJIMURA, Takashi KUDO, Shunsuke TAKUMA, Satoshi SHIMIZU
  • Publication number: 20220344365
    Abstract: An alternating stack of insulating layers and spacer material layers is formed over a substrate. A plurality of arrays of memory opening fill structures is formed through the alternating stack. A plurality of dielectric plates is formed, which laterally surrounds a respective array of memory opening fill structures. Self-aligned drain-select-level isolation structures are formed between a respective neighboring pair of arrays of memory opening fill structures through gaps between neighboring pairs of the dielectric plates into a subset of layers within the alternating stack. Drain side select gate electrodes are provided from a divided subset of the spacer material layers.
    Type: Application
    Filed: April 22, 2021
    Publication date: October 27, 2022
    Inventors: Nobuyuki FUJIMURA, Satoshi SHIMIZU, Takumi MORIYAMA
  • Patent number: 10879260
    Abstract: A bonded assembly includes a first memory die containing a first three-dimensional memory device, a second memory die containing a second three-dimensional memory device, and a support die bonded to the first memory die and comprising a peripheral circuitry configured to control the first three-dimensional memory device and the second three-dimensional memory device. The first memory die includes multiple rows of first-die proximal bonding pads, multiple rows of first-die distal bonding pads, and a plurality of first-die laterally-shifting electrically conductive paths connecting a respective one of the first-die proximal bonding pads and a respective one of the first-die distal bonding pads that is laterally offset from the respective one of the first-die proximal bonding pads. The first memory die and the second memory die can have an identical layout, and electrical connections can be shifted through the first memory die by the offset distance.
    Type: Grant
    Filed: February 28, 2019
    Date of Patent: December 29, 2020
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Tatsuya Uryu, Satoshi Shimizu, Nobuyuki Fujimura
  • Publication number: 20200279861
    Abstract: A bonded assembly includes a first memory die containing a first three-dimensional memory device, a second memory die containing a second three-dimensional memory device, and a support die bonded to the first memory die and comprising a peripheral circuitry configured to control the first three-dimensional memory device and the second three-dimensional memory device. The first memory die includes multiple rows of first-die proximal bonding pads, multiple rows of first-die distal bonding pads, and a plurality of first-die laterally-shifting electrically conductive paths connecting a respective one of the first-die proximal bonding pads and a respective one of the first-die distal bonding pads that is laterally offset from the respective one of the first-die proximal bonding pads. The first memory die and the second memory die can have an identical layout, and electrical connections can be shifted through the first memory die by the offset distance.
    Type: Application
    Filed: February 28, 2019
    Publication date: September 3, 2020
    Inventors: Tatsuya Uryu, Satoshi Shimizu, Nobuyuki Fujimura