Patents by Inventor Michiaki Sano

Michiaki Sano 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: 20200168623
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers containing word lines and drain select gate electrodes located over a substrate, and memory stack structures containing a respective vertical semiconductor channel and a memory film including a tunneling dielectric and a charge storage layer. A first portion of a first charge storage layer located in a first memory stack structure at level of a first drain select gate electrode is thicker than a first portion of a second charge storage layer located in a second memory stack structure at the level of the first drain select electrode.
    Type: Application
    Filed: November 28, 2018
    Publication date: May 28, 2020
    Inventors: Masatoshi NISHIKAWA, Michiaki SANO, Ken OOWADA, Zhixin CUI
  • Patent number: 10553599
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, memory openings vertically extending through the alternating stack, and memory opening fill structures located in the memory openings and including a respective memory-level semiconductor channel and a respective memory film. Drain-select-level gate electrodes overlie the alternating stack. Drain-select-level pillar structures extend through a respective one of the drain-select-level gate electrodes. Each drain-select-level semiconductor channel is electrically connected to an underlying one of the memory-level semiconductor channels. A planar insulating spacer layer having a homogeneous composition throughout directly contacts top surfaces of the memory films and bottom surfaces of the drain-select-level gate electrodes.
    Type: Grant
    Filed: September 26, 2018
    Date of Patent: February 4, 2020
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Zhen Chen, Michiaki Sano, Mitsuteru Mushiga
  • Patent number: 10468459
    Abstract: Systems and methods for implementing a memory array comprising vertical bit lines that are connected to different pairs of vertical thin-film transistors (TFTs) are described. A set of vertical TFTs may be formed such that a first TFT and a second TFT are spaced apart by a first separation distance and a third TFT and the second TFT are spaced apart by a second separation distance. The fabrication of the memory array includes forming a layer of conducting material with a thickness that is greater than half of the first separation distance and less than half of the second separation distance and then performing an anisotropic etch to remove portions of the conducting material such that openings in the conducting material are formed between the pairs of vertical TFTs while preventing openings from forming between the vertical TFTs of each pair of vertical TFTs.
    Type: Grant
    Filed: December 26, 2017
    Date of Patent: November 5, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yusuke Oda, Michiaki Sano
  • Publication number: 20190275459
    Abstract: A gas scrubber includes a canister having a rotatable spiral separator which provides a non-linear path configured to be filled with modular adsorbent material portions between a gas inlet and a gas outlet.
    Type: Application
    Filed: March 8, 2018
    Publication date: September 12, 2019
    Inventors: Michiaki SANO, Jo SATO
  • Patent number: 10381322
    Abstract: A first substrate has a first mesa structure that protrudes from a first bonding-side planar surface. A first metal pad structure is embedded within the first mesa structure. A second substrate has a first recess cavity that is recessed from a second bonding-side planar surface. A second metal pad structure is located at a recessed region of the first recess cavity. The first bonding-side planar surface and the second bonding-side planar surface are brought into physical contact with each other, while the first mesa structure is disposed within a volume of the first recess cavity by self-alignment. A gap is provided between the first metal pad structure and the second metal pad structure within a volume of the first recess cavity. A metal connection pad is formed by selectively growing a third metallic material from the first metal pad structure and the second metal pad structure.
    Type: Grant
    Filed: April 23, 2018
    Date of Patent: August 13, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yasunobu Azuma, Michiaki Sano
  • Publication number: 20190198568
    Abstract: Systems and methods for implementing a memory array comprising vertical bit lines that are connected to different pairs of vertical thin-film transistors (TFTs) are described. A set of vertical TFTs may be formed such that a first TFT and a second TFT are spaced apart by a first separation distance and a third TFT and the second TFT are spaced apart by a second separation distance. The fabrication of the memory array includes forming a layer of conducting material with a thickness that is greater than half of the first separation distance and less than half of the second separation distance and then performing an anisotropic etch to remove portions of the conducting material such that openings in the conducting material are formed between the pairs of vertical TFTs while preventing openings from forming between the vertical TFTs of each pair of vertical TFTs.
    Type: Application
    Filed: December 26, 2017
    Publication date: June 27, 2019
    Applicant: SANDISK TECHNOLOGIES LLC
    Inventors: Yusuke Oda, Michiaki Sano
  • Patent number: 10290803
    Abstract: A wedge-shaped contact region can be employed to provide electrical contacts to multiple electrically conductive layers in a three-dimensional device structure. A cavity including a generally wedge-shaped region and a primary region is formed in a dielectric matrix layer over a support structure. An alternating stack of insulating layers and electrically conductive layers is formed by a series of conformal deposition processes in the cavity and over the dielectric matrix layer. The alternating stack can be planarized employing the top surface of the dielectric matrix layer as a stopping layer. A tip portion of each electrically conductive layer within remaining portions of the alternating stack is laterally offset from the tip of the generally wedge-shaped region by a respective lateral offset distance along a lateral protrusion direction. Contact via structures can be formed on the tip portions of the electrically conductive layers to provide electrical contact.
    Type: Grant
    Filed: December 2, 2016
    Date of Patent: May 14, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Michiaki Sano, Zhen Chen, Tetsuya Yamada, Akira Nakada, Yasuke Oda, Manabu Hayashi, Shigenori Sato
  • Patent number: 10217746
    Abstract: A three-dimensional memory device includes a first alternating stack of first insulating layers and first electrically conductive layers located over a top surface of a substrate, such that each of the first insulating layers and the first electrically conductive layers includes a respective horizontally-extending portion and a respective non-horizontally-extending portion, memory stack structures extending through a memory array region of the first alternating stack that includes the horizontally-extending portions of the first electrically conductive layers, such that each of the memory stack structures comprises a memory film and a vertical semiconductor channel, a mesa structure located over the substrate, such that each respective non-horizontally-extending portion of the first insulating layers and the first electrically conductive layers is located over a sidewall of the mesa structure, and contact structures that contact a respective one of the non-horizontally-extending portions of the first electric
    Type: Grant
    Filed: January 11, 2018
    Date of Patent: February 26, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Tae-Kyung Kim, Raghuveer S. Makala, Yanli Zhang, Hiroyuki Kinoshita, Daxin Mao, Jixin Yu, Yiyang Gong, Kazuto Watanabe, Michiaki Sano, Haruki Urata, Akira Takahashi
  • Patent number: 10209636
    Abstract: Pattern-dependent random deviations in measurement of optimal focus distances can be minimized by separating scan paths into multiple types of scan paths that scan only a respective predetermined image region in semiconductor dies. A substrate including in-process semiconductor dies is coated with a photoresist layer, and is located onto a stage in a lithographic exposure tool. Maps of optimal focus distances are generated by performing optimal focus distance scans that cover a respective subset of image regions having distinct image patterns. The substrate can be leveled with respect to an optics system of the lithographic exposure tool employing a weighted average of multiple maps of optimal focus distances. Once the substrate is leveled on the stage, a lithographic exposure process can be performed with enhanced uniformity in the focus distances across the in-process semiconductor dies.
    Type: Grant
    Filed: March 7, 2018
    Date of Patent: February 19, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Tohru Toda, Keisuke Izumi, Michiaki Sano
  • Patent number: 10211215
    Abstract: An alternating stack of insulating layers and spacer material layers is formed over a substrate. Each of the first insulating layers and the first sacrificial material layers includes a respective horizontally-extending portion and a respective non-horizontally-extending portion. Memory stack structures are formed through the horizontally-extending portions of the alternating stack. Regions of the non-horizontally-extending portions of the sacrificial material layers are masked with patterned etch mask portions. Unmasked first regions of the non-horizontally-extending portions of the first sacrificial material layers are selectively recessed, and the sacrificial material layers with electrically conductive layers. Each electrically conductive layer can include a vertical plate region and a protrusion region that protrudes above the vertical plate region and having a narrower lateral dimension that the vertical plate region.
    Type: Grant
    Filed: February 13, 2018
    Date of Patent: February 19, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yashushi Ishii, Kazuto Watanabe, Michiaki Sano, Haruki Urata, Akira Takahashi, Tae-Kyung Kim
  • Patent number: 10181442
    Abstract: A three-dimensional memory device includes an alternating stack of L-shaped insulating layers and L-shaped electrically conductive layers located over a top surface of a substrate, such that each of the L-shaped insulating layers and the L-shaped electrically conductive layers includes a respective horizontally-extending portion and a respective non-horizontally-extending portion, memory stack structures extending through a memory array region of the alternating stack that includes the horizontally-extending portions of the L-shaped electrically conductive layers, such that each of the memory stack structures includes a memory film and a vertical semiconductor channel, dielectric spacers non-horizontally extending between neighboring pairs of a non-horizontally-extending portion of an L-shaped insulating layer and a non-horizontally-extending portion of an L-shaped electrically conductive layer, and contact via structures that contact a respective one of the non-horizontally-extending portions of the L-shaped
    Type: Grant
    Filed: November 30, 2017
    Date of Patent: January 15, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Kazuto Watanabe, Michiaki Sano, Haruki Urata, Akira Takahashi
  • Patent number: 10115770
    Abstract: A method is provided that includes forming a dielectric material and a first sacrificial material above a substrate, forming a second sacrificial material above the substrate and disposed adjacent the dielectric material and the first sacrificial material, forming a first hole in the second sacrificial material, the first hole disposed in a first direction, forming a word line layer above the substrate via the first hole, the word line layer disposed in a second direction perpendicular to the first direction, forming a first portion of a nonvolatile memory material on peripheral sides of the word line layer via the first hole, forming a second hole in the second sacrificial material, forming a second portion of the nonvolatile memory material on a sidewall of the second hole, forming a local bit line in the second hole, and forming a memory cell including the nonvolatile memory material at an intersection of the local bit line and the word line layer.
    Type: Grant
    Filed: February 28, 2017
    Date of Patent: October 30, 2018
    Assignee: SanDisk Technologies LLC
    Inventors: Jongsun Sel, Daewung Kang, Michiaki Sano, Yohei Yamada, Mitsuteru Mushiga, Tuan Pham
  • Patent number: 10115735
    Abstract: A semiconductor device includes a silicon surface, a titanium silicide layer contacting the silicon surface, a first titanium nitride layer located over the titanium silicide layer, a titanium oxynitride layer contacting the first titanium nitride layer, a second titanium nitride layer contacting the titanium oxynitride layer, and a metal fill layer located over the second titanium nitride layer.
    Type: Grant
    Filed: June 8, 2017
    Date of Patent: October 30, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Fumitaka Amano, Kensuke Ishikawa, Shinya Inoue, Michiaki Sano
  • Patent number: 10083982
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, the alternating stack having a memory array region and a contact region containing stepped surfaces, and memory stack structures having a semiconductor channel and a memory film extending through the memory array region of the alternating stack. The electrically conductive layers include a drain select gate electrode and word lines, where the drain select gate electrode is thicker than each of the word lines.
    Type: Grant
    Filed: April 25, 2017
    Date of Patent: September 25, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Keisuke Shigemura, Junichi Ariyoshi, Masanori Tsutsumi, Michiaki Sano, Yanli Zhang, Raghuveer S. Makala
  • Patent number: 10083877
    Abstract: A two-dimensional array of vertical field effect transistors is provided, which includes a first-tier structure and a second-tier structure. The first-tier structure includes a laterally alternating sequence of semiconductor rail structures and first dielectric isolation rails that alternates along a first horizontal direction. A first gate dielectric and a first gate electrode that laterally extend along a second horizontal direction are disposed between each neighboring pair of a semiconductor rail structure and a first dielectric isolation rail. The second-tier structure includes a laterally alternating sequence of composite rail structures and second dielectric isolation rails that alternates along the second horizontal direction. Each of the composite rail structures includes a laterally alternating plurality of semiconductor pillar structures and dielectric pillar structures.
    Type: Grant
    Filed: October 25, 2017
    Date of Patent: September 25, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Michiaki Sano, Tetsuya Yamada
  • Publication number: 20180247976
    Abstract: A method is provided that includes forming a dielectric material and a first sacrificial material above a substrate, forming a second sacrificial material above the substrate and disposed adjacent the dielectric material and the first sacrificial material, forming a first hole in the second sacrificial material, the first hole disposed in a first direction, forming a word line layer above the substrate via the first hole, the word line layer disposed in a second direction perpendicular to the first direction, forming a first portion of a nonvolatile memory material on peripheral sides of the word line layer via the first hole, forming a second hole in the second sacrificial material, forming a second portion of the nonvolatile memory material on a sidewall of the second hole, forming a local bit line in the second hole, and forming a memory cell including the nonvolatile memory material at an intersection of the local bit line and the word line layer.
    Type: Application
    Filed: February 28, 2017
    Publication date: August 30, 2018
    Applicant: SANDISK TECHNOLOGIES LLC
    Inventors: Jongsun Sel, Daewung Kang, Michiaki Sano, Yohei Yamada, Mitsuteru Mushiga, Tuan Pham
  • Publication number: 20180247954
    Abstract: A semiconductor device includes a silicon surface, a titanium silicide layer contacting the silicon surface, a first titanium nitride layer located over the titanium silicide layer, a titanium oxynitride layer contacting the first titanium nitride layer, a second titanium nitride layer contacting the titanium oxynitride layer, and a metal fill layer located over the second titanium nitride layer.
    Type: Application
    Filed: June 8, 2017
    Publication date: August 30, 2018
    Inventors: Fumitaka Amano, Kensuke Ishikawa, Shinya Inoue, Michiaki Sano
  • Publication number: 20180158873
    Abstract: A wedge-shaped contact region can be employed to provide electrical contacts to multiple electrically conductive layers in a three-dimensional device structure. A cavity including a generally wedge-shaped region and a primary region is formed in a dielectric matrix layer over a support structure. An alternating stack of insulating layers and electrically conductive layers is formed by a series of conformal deposition processes in the cavity and over the dielectric matrix layer. The alternating stack can be planarized employing the top surface of the dielectric matrix layer as a stopping layer. A tip portion of each electrically conductive layer within remaining portions of the alternating stack is laterally offset from the tip of the generally wedge-shaped region by a respective lateral offset distance along a lateral protrusion direction. Contact via structures can be formed on the tip portions of the electrically conductive layers to provide electrical contact.
    Type: Application
    Filed: December 2, 2016
    Publication date: June 7, 2018
    Inventors: Michiaki SANO, Zhen CHEN, Tetsuya YAMADA, Akira NAKADA, Yasuke ODA, Manabu HAYASHI, Shigenori SATO
  • Publication number: 20180138194
    Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, the alternating stack having a memory array region and a contact region containing stepped surfaces, and memory stack structures having a semiconductor channel and a memory film extending through the memory array region of the alternating stack. The electrically conductive layers include a drain select gate electrode and word lines, where the drain select gate electrode is thicker than each of the word lines.
    Type: Application
    Filed: April 25, 2017
    Publication date: May 17, 2018
    Inventors: Keisuke SHIGEMURA, Junichi ARIYOSHI, Masanori TSUTSUMI, Michiaki SANO, Yanli ZHANG, Raghuveer S. MAKALA
  • Patent number: 9911790
    Abstract: A plurality of alternating stacks laterally spaced apart by line trenches is provided over a substrate. Each alternating stack includes respective word lines and respective dielectric material layers. An alternating sequence of vertical bit lines and inter-bit-line cavities is formed within each of the line trenches. Resistive memory material layers including resistive memory elements are provided at intersection regions between the word lines and the vertical bit lines. Air gaps are formed by removing at least a predominant portion of each of the dielectric material layers selective to the word lines, the vertical bit lines, and the resistive memory material layers, thereby forming a plurality of alternating stacks of the word lines and air gaps. A dielectric isolation layer including vertically-extending voids can be formed over the plurality of alternating stacks in the inter-bit-line cavities.
    Type: Grant
    Filed: January 20, 2017
    Date of Patent: March 6, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Seiji Shimabukuro, Michiaki Sano, Kan Fujiwara