Patents by Inventor Kiyokazu Shishido

Kiyokazu Shishido 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: 20240147730
    Abstract: A lateral extent of a gate electrode of a field effect transistor along a gate electrode direction that is perpendicular to a channel direction can be the same as a width of an underlying active region. A gate electrode of an additional field effect transistor may extend over a trench isolation structure that laterally surrounds the additional field effect transistor. Different types of electrodes may be formed by patterning a lower gate material layer and by patterning an upper gate material layer with different patterns such that patterned portions of the lower gate material layer are confined within areas of active regions, while patterned portions of the upper gate material layer extends outside of the areas of the active regions.
    Type: Application
    Filed: November 2, 2023
    Publication date: May 2, 2024
    Inventors: Kiyokazu SHISHIDO, Kazutaka YOSHIZAWA, Dai IWATA, Hokuto KODATE
  • Publication number: 20240111440
    Abstract: A three dimensional non-volatile memory structure includes word lines connected to non-volatile memory cells arranged in blocks. A plurality of word line switches are connected to the word lines and one or more sources of voltage. The word line switches are arranged in groups of X word line switches such that each group of X word line switches is positioned in a line under Y blocks of non-volatile memory cells and has a length that is equal to the width of the Y blocks of non-volatile memory cells. To allow closer placement of word line switches that supply different blocks and support the possible large voltage differences between their transistors, word line switches supplying different blocks are formed over a single active region and separated by an intermediate control gate set to be off.
    Type: Application
    Filed: September 30, 2022
    Publication date: April 4, 2024
    Applicant: SanDisk Technologies LLC
    Inventors: Yuki Mizutani, Kazutaka Yoshizawa, Kiyokazu Shishido, Eiichi Fujikura
  • Patent number: 11876096
    Abstract: A semiconductor structure includes at least two field effect transistors. A gate strip including a plurality of gate dielectrics and a gate electrode strip can be formed over a plurality of semiconductor active regions. Source/drain implantation is conducted using the gate strip as a mask. The gate strip is divided into gate electrodes after the implantation.
    Type: Grant
    Filed: October 7, 2021
    Date of Patent: January 16, 2024
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Takahito Fujita, Hiroyuki Ogawa, Kiyokazu Shishido
  • Patent number: 11710740
    Abstract: A semiconductor structure includes at least two field effect transistors. A gate strip including a plurality of gate dielectrics and a gate electrode strip can be formed over a plurality of semiconductor active regions. Source/drain implantation is conducted using the gate strip as a mask. The gate strip is divided into gate electrodes after the implantation.
    Type: Grant
    Filed: October 7, 2021
    Date of Patent: July 25, 2023
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Takahito Fujita, Hiroyuki Ogawa, Kiyokazu Shishido
  • Publication number: 20230111003
    Abstract: A semiconductor structure includes at least two field effect transistors. A gate strip including a plurality of gate dielectrics and a gate electrode strip can be formed over a plurality of semiconductor active regions. Deep source/drain regions are formed by implanting dopants into semiconductor active regions without implanting the dopants into inter-electrode regions of a shallow trench isolation structure. The gate strip is divided into gate stacks prior to or after formation of the deep source/drain regions.
    Type: Application
    Filed: November 18, 2021
    Publication date: April 13, 2023
    Inventors: Takahito FUJITA, Kiyokazu SHISHIDO, Hiroyuki OGAWA
  • Publication number: 20230111724
    Abstract: A semiconductor structure includes at least two field effect transistors. A gate strip including a plurality of gate dielectrics and a gate electrode strip can be formed over a plurality of semiconductor active regions. Source/drain implantation is conducted using the gate strip as a mask. The gate strip is divided into gate electrodes after the implantation.
    Type: Application
    Filed: October 7, 2021
    Publication date: April 13, 2023
    Inventors: Takahito FUJITA, Hiroyuki OGAWA, Kiyokazu SHISHIDO
  • Publication number: 20230112262
    Abstract: A semiconductor structure includes at least two field effect transistors. A gate strip including a plurality of gate dielectrics and a gate electrode strip can be formed over a plurality of semiconductor active regions. Source/drain implantation is conducted using the gate strip as a mask. The gate strip is divided into gate electrodes after the implantation.
    Type: Application
    Filed: October 7, 2021
    Publication date: April 13, 2023
    Inventors: Takahito FUJITA, Hiroyuki OGAWA, Kiyokazu SHISHIDO
  • Patent number: 11069707
    Abstract: A semiconductor die includes alternating stacks of insulating layers and electrically conductive layers that are laterally separated from each other by first backside trenches that laterally extend along a first horizontal direction, an array of memory stack structures vertically extending through the alternating sacks, an inner edge seal structure that continuously laterally surrounds the alternating stacks, an outer edge seal structure that continuously laterally surrounds the inner edge seal structure, and additional alternating stacks of insulating layers and electrically conductive layers located between the inner edge seal structure and the outer edge seal structure.
    Type: Grant
    Filed: October 29, 2019
    Date of Patent: July 20, 2021
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Tomoka Tanabe, Hiroyuki Ogawa, Kiyokazu Shishido, Takahito Fujita
  • Publication number: 20210126008
    Abstract: A semiconductor die includes alternating stacks of insulating layers and electrically conductive layers that are laterally separated from each other by first backside trenches that laterally extend along a first horizontal direction, an array of memory stack structures vertically extending through the alternating sacks, an inner edge seal structure that continuously laterally surrounds the alternating stacks, an outer edge seal structure that continuously laterally surrounds the inner edge seal structure, and additional alternating stacks of insulating layers and electrically conductive layers located between the inner edge seal structure and the outer edge seal structure.
    Type: Application
    Filed: October 29, 2019
    Publication date: April 29, 2021
    Inventors: Tomoka TANABE, Hiroyuki OGAWA, Kiyokazu SHISHIDO, Takahito FUJITA
  • Patent number: 10804284
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, memory stack structures vertically extending through the alternating stack, each memory stack structure including a memory film and a vertical semiconductor channel, and a contact well set that includes contact wells extending through a respective upper region of the alternating stack. Each of the contact wells contains first stepped surfaces which have a stepwise descending vertical profile along a first horizontal direction and second stepped surfaces which have a stepwise descending vertical profile along a second horizontal direction which is perpendicular to the first horizontal direction.
    Type: Grant
    Filed: April 11, 2018
    Date of Patent: October 13, 2020
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yasushi Ishii, Jun Akaiwa, Kiyokazu Shishido, Hiroyuki Ogawa
  • Patent number: 10770459
    Abstract: A silicon oxide liner, a silicon nitride liner, and a planarization silicon oxide layer may be sequentially formed over p-type and n-type field effect transistors. A patterned dielectric material layer covers an entirety of the n-type field effect transistor and does not cover at least a fraction of each area of p-doped active regions. An anisotropic etch process is performed to form p-type active region via cavities extending to a respective top surface of the p-doped active regions and n-type active region via cavities having a respective bottom surface at, or within, one of the silicon nitride liner and the silicon oxide liner. Boron-doped epitaxial pillar structures may be formed on top surfaces of the p-type active regions employing a selective epitaxy process. The n-type active region via cavities are extended to top surfaces of the n-doped active regions. Contact via structures are formed in the via cavities.
    Type: Grant
    Filed: December 20, 2018
    Date of Patent: September 8, 2020
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Dai Iwata, Yasushi Ishii, Hiroshi Nakatsuji, Kiyokazu Shishido, Hiroyuki Ogawa
  • Patent number: 10515907
    Abstract: A semiconductor structure includes a semiconductor device, an overlying silicon nitride diffusion barrier layer, and an interconnect structure extending through the silicon nitride diffusion barrier layer. The interconnect structure includes a titanium diffusion barrier structure in contact with the silicon nitride diffusion barrier layer to form a continuous hydrogen diffusion barrier structure.
    Type: Grant
    Filed: May 17, 2018
    Date of Patent: December 24, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Takahito Fujita, Kiyokazu Shishido, Hiroyuki Ogawa
  • Patent number: 10515897
    Abstract: A semiconductor structure includes a semiconductor device, an overlying silicon nitride diffusion barrier layer, and an interconnect structure extending through the silicon nitride diffusion barrier layer. The interconnect structure includes a titanium diffusion barrier structure in contact with the silicon nitride diffusion barrier layer to form a continuous hydrogen diffusion barrier structure.
    Type: Grant
    Filed: May 17, 2018
    Date of Patent: December 24, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Masatoshi Nishikawa, Akio Nishida, Murshed Chowdhury, Takahito Fujita, Kiyokazu Shishido, Hiroyuki Ogawa
  • Publication number: 20190355663
    Abstract: A semiconductor structure includes a semiconductor device, an overlying silicon nitride diffusion barrier layer, and an interconnect structure extending through the silicon nitride diffusion barrier layer. The interconnect structure includes a titanium diffusion barrier structure in contact with the silicon nitride diffusion barrier layer to form a continuous hydrogen diffusion barrier structure.
    Type: Application
    Filed: May 17, 2018
    Publication date: November 21, 2019
    Inventors: Masatoshi NISHIKAWA, Akio NISHIDA, Murshed CHOWDHURY, Takahito FUJITA, Kiyokazu SHISHIDO, Hiroyuki OGAWA
  • Publication number: 20190355672
    Abstract: A semiconductor structure includes a semiconductor device, an overlying silicon nitride diffusion barrier layer, and an interconnect structure extending through the silicon nitride diffusion barrier layer. The interconnect structure includes a titanium diffusion barrier structure in contact with the silicon nitride diffusion barrier layer to form a continuous hydrogen diffusion barrier structure.
    Type: Application
    Filed: May 17, 2018
    Publication date: November 21, 2019
    Inventors: Takahito FUJITA, Kiyokazu SHISHIDO, Hiroyuki OGAWA
  • Publication number: 20190319040
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, memory stack structures vertically extending through the alternating stack, each memory stack structure including a memory film and a vertical semiconductor channel, and a contact well set that includes contact wells extending through a respective upper region of the alternating stack. Each of the contact wells contains first stepped surfaces which have a stepwise descending vertical profile along a first horizontal direction and second stepped surfaces which have a stepwise descending vertical profile along a second horizontal direction which is perpendicular to the first horizontal direction.
    Type: Application
    Filed: April 11, 2018
    Publication date: October 17, 2019
    Inventors: Yasushi Ishii, Jun Akaiwa, Kiyokazu Shishido, Hiroyuki Ogawa
  • Publication number: 20190296012
    Abstract: A silicon oxide liner, a silicon nitride liner, and a planarization silicon oxide layer may be sequentially formed over p-type and n-type field effect transistors. A patterned dielectric material layer covers an entirety of the n-type field effect transistor and does not cover at least a fraction of each area of p-doped active regions. An anisotropic etch process is performed to form p-type active region via cavities extending to a respective top surface of the p-doped active regions and n-type active region via cavities having a respective bottom surface at, or within, one of the silicon nitride liner and the silicon oxide liner. Boron-doped epitaxial pillar structures may be formed on top surfaces of the p-type active regions employing a selective epitaxy process. The n-type active region via cavities are extended to top surfaces of the n-doped active regions. Contact via structures are formed in the via cavities.
    Type: Application
    Filed: December 20, 2018
    Publication date: September 26, 2019
    Inventors: Dai Iwata, Yasushi Ishii, Hiroshi Nakatsuji, Kiyokazu Shishido, Hiroyuki Ogawa
  • Patent number: 10355017
    Abstract: A CMOS device includes a p-type field effect transistor containing p-doped active regions, an n-type field effect transistor containing n-doped active regions, a silicon oxide layer overlying the n-type field effect transistor and not overlying the p-type field effect transistor, boron-doped epitaxial pillar structures contacting a top surface of, and epitaxially aligned to, a respective one of the p-doped active regions, first active region contact via structures contacting a top surface of a respective one of the boron-doped epitaxial pillar structures, and second active region contact via structures contacting a top surface of a respective one of the n-doped active regions.
    Type: Grant
    Filed: June 13, 2018
    Date of Patent: July 16, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Hiroshi Nakatsuji, Kiyokazu Shishido, Hiroyuki Ogawa
  • Patent number: 10256099
    Abstract: A semiconductor structure, such as a CMOS device, includes a first field effect transistor and a second field effect transistor. The first field effect transistor includes a first composite gate electrode containing a first vertical stack of a p-doped semiconductor gate electrode, a first interfacial dielectric layer, and a first metallic gate electrode. The second field effect transistor includes a second composite gate electrode containing a second vertical stack that includes an n-doped semiconductor gate electrode and a second metallic gate electrode. A second interfacial dielectric layer having a second thickness that is thinner than the first interfacial dielectric layer may, or may not, be present in the second composite gate electrode.
    Type: Grant
    Filed: March 9, 2018
    Date of Patent: April 9, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Jun Akaiwa, Kiyokazu Shishido, Hiroyuki Ogawa
  • Patent number: 9607997
    Abstract: A wide trench having a width W1 and narrow trenches having a width W2 that is less than W1 are formed in a dielectric layer, the wide trench extending deeper in outer regions than in a central region. A trench modification step changes the width of the wide trench and reduces a depth difference between the outer regions and the central region of the wide trench.
    Type: Grant
    Filed: September 8, 2015
    Date of Patent: March 28, 2017
    Assignee: SANDISK TECHNOLOGIES INC.
    Inventors: Katsuo Yamada, Yuji Takahashi, Noritaka Fukuo, Masami Uozaki, Kiyokazu Shishido, Takuya Futase, Shunsuke Watanabe