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).

  • Patent number: 9673304
    Abstract: A method is provided that includes forming a dielectric material above a substrate, forming a hole in the dielectric material, the hole disposed in a first direction, forming a word line layer above the substrate via the hole, the word line layer disposed in a second direction perpendicular to the first direction, forming a nonvolatile memory material on a sidewall of the hole, forming a local bit line in the 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: July 15, 2016
    Date of Patent: June 6, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Michiaki Sano, Akira Nakada, Tetsuya Yamada, Manabu Hayashi, Takashi Matsubara, Sung Tae Lee, Akio Nishida
  • Patent number: 9666799
    Abstract: An alternating stack of electrically conductive layers and electrically insulating layers is formed over global bit lines formed on a substrate. The alternating stack is patterned to form a line stack of electrically conductive lines and electrically insulating lines. Trench isolation structures are formed within each trench to define a plurality of memory openings laterally spaced from one another by the line stack in one direction and by trench isolation structures in another direction. The electrically conductive lines are laterally recessed relative to sidewall surfaces of the electrically insulating lines. A read/write memory material is deposited in recesses, and is anisotropically etched so that a top surface of a global bit line is physically exposed at a bottom of each memory opening. An electrically conductive bit line is formed within each memory opening to form a resistive random access memory device.
    Type: Grant
    Filed: October 31, 2014
    Date of Patent: May 30, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Naohito Yanagida, Cheng Feng, Michiaki Sano, Akira Nakada, Steven J. Radigan, Eiji Hayashi
  • Patent number: 9620712
    Abstract: An alternating stack of electrically conductive layers and electrically insulating layers is formed over global bit lines formed on a substrate. The alternating stack is patterned to form a line stack of electrically conductive lines and electrically insulating lines. Trench isolation structures are formed within each trench to define a plurality of memory openings laterally spaced from one another by the line stack in one direction and by trench isolation structures in another direction. The electrically conductive lines are laterally recessed relative to sidewall surfaces of the electrically insulating lines. A read/write memory material is deposited in recesses, and is anisotropically etched so that a top surface of a global bit line is physically exposed at a bottom of each memory opening. An electrically conductive bit line is formed within each memory opening to form a resistive random access memory device.
    Type: Grant
    Filed: October 31, 2014
    Date of Patent: April 11, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Eiji Hayashi, Naohito Yanagida, Michiaki Sano, Akira Nakada
  • Patent number: 9601502
    Abstract: A recessed region can be formed on a semiconductor substrate, and peripheral semiconductor devices can be formed on a recessed horizontal surface of the semiconductor substrate. An alternating stack of insulating layers and sacrificial material layers are formed over the semiconductor substrate, and memory stack structures are formed therethrough. Contact openings extending to sacrificial material layers located at different depths can be formed by sequentially exposing a greater number of openings in a mask layer by iterative alternation of trimming of a slimming layer over the mask layer and an anisotropic etch that recesses pre-existing contact openings by one level. Electrically conductive via structures extending to electrically conductive electrodes located at different level can be provided with self-aligned insulating liners.
    Type: Grant
    Filed: July 15, 2016
    Date of Patent: March 21, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Michiaki Sano, Keisuke Izumi
  • Patent number: 9576967
    Abstract: Memory openings and support openings are formed through an alternating stack of insulating layers and spacer material layers over a semiconductor substrate. Deposition of a semiconductor material in the support openings during formation of epitaxial channel portions in the memory openings is prevented by Portions of the semiconductor substrate that underlie the support openings are converted into impurity-doped semiconductor material portions. During selective growth of epitaxial channel portions from the semiconductor substrate within the memory openings, growth of a semiconductor material in the support openings is suppressed due to the impurity species in the impurity-doped semiconductor material portions. Memory stack structures and support pillar structures are subsequently formed over the epitaxial channel portions and in the support openings, respectively.
    Type: Grant
    Filed: June 30, 2016
    Date of Patent: February 21, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Hajime Kimura, Seiji Shimabukuro, Shuji Minagawa, Michiaki Sano, Masanori Tsutsumi
  • Patent number: 9524901
    Abstract: A method of making multi-level contacts includes providing an in-process multilevel device having a device region and a contact region including a stack of alternating sacrificial layers and insulating layers located over a major surface of a substrate. A contact mask having contact mask openings is provided over the stack, and a first over mask having first over mask openings is provided over the contact mask. A subset of the contact mask openings is substantially aligned with the first over mask openings. Contact openings are formed through the stack, wherein each of the contact openings extends substantially perpendicular to the major surface of the substrate to a respective one of the sacrificial layers. A plurality of electrically conductive via contacts is formed in the plurality of the contact openings.
    Type: Grant
    Filed: September 30, 2014
    Date of Patent: December 20, 2016
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Keisuke Izumi, Michiaki Sano, Hiroshi Sasaki
  • Publication number: 20160322374
    Abstract: A recessed region can be formed on a semiconductor substrate, and peripheral semiconductor devices can be formed on a recessed horizontal surface of the semiconductor substrate. An alternating stack of insulating layers and sacrificial material layers are formed over the semiconductor substrate, and memory stack structures are formed therethrough. Contact openings extending to sacrificial material layers located at different depths can be formed by sequentially exposing a greater number of openings in a mask layer by iterative alternation of trimming of a slimming layer over the mask layer and an anisotropic etch that recesses pre-existing contact openings by one level. Electrically conductive via structures extending to electrically conductive electrodes located at different level can be provided with self-aligned insulating liners.
    Type: Application
    Filed: July 15, 2016
    Publication date: November 3, 2016
    Inventors: Michiaki SANO, Keisuke IZUMI
  • Patent number: 9437543
    Abstract: A contact via cavity can be filled with a lower structure and an upper structure. The lower structure can be a conductive structure that is formed by depositing a conformal conductive material, and subsequently removing an upper portion of the conformal conductive material. A disposable material portion can be formed at a bottom of the cavity to protect the bottom portion of the conformal conductive layer during removal of the upper portion. After removal of the disposable material, at least one conductive material can fill the remainder of the cavity to form the upper structure. The upper structure and the lower structure collectively constitute a contact via structure. Alternatively, the lower structure can be a dielectric spacer with an opening therethrough. The upper structure can be a conductive structure that extends through the dielectric spacer, and provides an electrically conductive vertical connection.
    Type: Grant
    Filed: January 22, 2015
    Date of Patent: September 6, 2016
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Akira Nakada, Michiaki Sano, Motoki Kawasaki, Sung Tae Lee
  • Patent number: 9412753
    Abstract: A method of making multi-level contacts includes providing an in-process multilevel device having a device region and a contact region including a stack of a plurality of alternating sacrificial layers and insulator layers located over a major surface of a substrate. A contact mask with at least one contact mask opening and at least one first terrace mask opening is provided over the stack, where the at least one first terrace mask opening is larger than the at least one contact mask opening. At least one first contact opening and at least one first terrace opening are simultaneously formed extending substantially perpendicular to the major surface of the substrate through the stack to a first sacrificial layer by etching a portion of the stack through the at least one contact mask opening and the at least one first terrace mask opening. A first electrically conductive via contact is deposited in the at least one first contact opening.
    Type: Grant
    Filed: September 30, 2014
    Date of Patent: August 9, 2016
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Keisuke Izumi, Michiaki Sano, Hiroshi Sasaki
  • Publication number: 20160218059
    Abstract: A contact via cavity can be filled with a lower structure and an upper structure. The lower structure can be a conductive structure that is formed by depositing a conformal conductive material, and subsequently removing an upper portion of the conformal conductive material. A disposable material portion can be formed at a bottom of the cavity to protect the bottom portion of the conformal conductive layer during removal of the upper portion. After removal of the disposable material, at least one conductive material can fill the remainder of the cavity to form the upper structure. The upper structure and the lower structure collectively constitute a contact via structure. Alternatively, the lower structure can be a dielectric spacer with an opening therethrough. The upper structure can be a conductive structure that extends through the dielectric spacer, and provides an electrically conductive vertical connection.
    Type: Application
    Filed: January 22, 2015
    Publication date: July 28, 2016
    Inventors: Akira NAKADA, Michiaki SANO, Motoki KAWASAKI, Sung Tae LEE
  • Patent number: 9401309
    Abstract: Contact openings extending to sacrificial layers located at different depths can be formed by sequentially exposing a greater number of openings in a mask layer by iterative alternation of trimming of a slimming layer over the mask layer and an anisotropic etch that recesses pre-existing contact openings by one level. In one embodiment, pairs of an electrically conductive via contact and electrically conductive electrodes can be simultaneously formed as integrated line and via structures. In another embodiment, encapsulated unfilled cavities can be formed in the contact openings by non-conformal deposition of a material layer, electrically conductive electrodes can be formed by replacement of portions of the sacrificial layers, and the electrically conductive via contacts can be subsequently formed on the electrically conductive electrodes. Electrically conductive via contacts extending to electrically conductive electrodes located at different level can be provided with self-aligned insulating liner.
    Type: Grant
    Filed: August 26, 2014
    Date of Patent: July 26, 2016
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Keisuke Izumi, Naohito Yanagida, Michiaki Sano, Takehiro Yamazaki, Hiroaki Iuchi, Akio Yanai, Genta Mizuno, Minoru Yamaguchi
  • Patent number: 9368601
    Abstract: A fabrication process for a vertical channel transistor provides a desired control gate-to-drain overlap and sufficient isolation between the control gate and an underlying metal line. A body of the transistor is formed on a metal line, such as in a pillar shape. The metal line is oxidized to form metal oxide regions having an expanded volume. A gate insulator material and a control gate material are then deposited. The resulting structure is etched to form separate control gates for each transistor, and to expose the metal oxide. A further etch is performed to remove the metal oxide, forming voids under and around the control gates. An insulation fills the voids. An example implementation is a vertical bit line memory device in which the transistors connect a vertical bit line to a horizontal bit line.
    Type: Grant
    Filed: February 28, 2014
    Date of Patent: June 14, 2016
    Assignee: SanDisk Technologies Inc.
    Inventors: Michiaki Sano, Kensuke Yamaguchi, Akira Nakada, Naohito Yanagida
  • Publication number: 20160148835
    Abstract: A trench can be formed through a stack of alternating plurality of first material layers and second material layers. A dielectric material liner and a trench fill material portion can be formed in the trench. The dielectric material liner and portions of first material layer can be simultaneously etched to form laterally-extending cavities having level-dependent lateral extents. A set of stepped surfaces can be formed by removing unmasked portions of the second material layers. Alternately, an alternating sequence of processing steps including vertical etch processes and lateral recess processes can be employed to laterally recess second material layers and to form laterally-extending cavities having level-dependent lateral extents. Lateral cavities can be simultaneously formed in multiple levels such that levels having laterally-extending cavities of a same lateral extent are offset across multiple integrated cavities.
    Type: Application
    Filed: November 26, 2014
    Publication date: May 26, 2016
    Inventors: Seiji SHIMABUKURO, Hiroaki IUCHI, Michiaki SANO, Naoki TAKEGUCHI
  • Publication number: 20160126292
    Abstract: An alternating stack of electrically conductive layers and electrically insulating layers is formed over global bit lines formed on a substrate. The alternating stack is patterned to form a line stack of electrically conductive lines and electrically insulating lines. Trench isolation structures are formed within each trench to define a plurality of memory openings laterally spaced from one another by the line stack in one direction and by trench isolation structures in another direction. The electrically conductive lines are laterally recessed relative to sidewall surfaces of the electrically insulating lines. A read/write memory material is deposited in recesses, and is anisotropically etched so that a top surface of a global bit line is physically exposed at a bottom of each memory opening. An electrically conductive bit line is formed within each memory opening to form a resistive random access memory device.
    Type: Application
    Filed: October 31, 2014
    Publication date: May 5, 2016
    Inventors: Naohito Yanagida, Cheng Feng, Michiaki Sano, Akira Nakada, Steven J. Radigan, Eiji Hayashi
  • Publication number: 20160126455
    Abstract: An alternating stack of electrically conductive layers and electrically insulating layers is formed over global bit lines formed on a substrate. The alternating stack is patterned to form a line stack of electrically conductive lines and electrically insulating lines. Trench isolation structures are formed within each trench to define a plurality of memory openings laterally spaced from one another by the line stack in one direction and by trench isolation structures in another direction. The electrically conductive lines are laterally recessed relative to sidewall surfaces of the electrically insulating lines. A read/write memory material is deposited in recesses, and is anisotropically etched so that a top surface of a global bit line is physically exposed at a bottom of each memory opening. An electrically conductive bit line is formed within each memory opening to form a resistive random access memory device.
    Type: Application
    Filed: October 31, 2014
    Publication date: May 5, 2016
    Inventors: Eiji Hayashi, Naohito Yanagida, Michiaki Sano, Akira Nakada
  • Publication number: 20160111439
    Abstract: A method of minimizing an overetch or damage to a semiconductor surface underneath a memory opening is provided. A first blocking dielectric layer is formed in a memory opening through a stack of an alternating plurality of material layers and insulator layers. A sacrificial liner is formed over the first blocking dielectric layer. An opening is formed through a horizontal portion of the sacrificial liner. A horizontal portion of the first blocking dielectric layer at a bottom of the memory opening can be etched through the opening in the sacrificial liner. A semiconductor surface of the substrate can be physically exposed at a bottom of the memory opening with minimal overetch and/or surface damage. A second blocking dielectric layer can be formed, before or after formation of the sacrificial liner, to provide a multilayer blocking dielectric.
    Type: Application
    Filed: October 21, 2014
    Publication date: April 21, 2016
    Inventors: Masanori Tsutsumi, Hiroshi Sasaki, Hiroyuki Ogawa, Michiaki Sano, Masato Miyamoto, Kensuke Yamaguchi, Seiji Shimabukuro
  • Patent number: 9305937
    Abstract: A method of minimizing an overetch or damage to a semiconductor surface underneath a memory opening is provided. A first blocking dielectric layer is formed in a memory opening through a stack of an alternating plurality of material layers and insulator layers. A sacrificial liner is formed over the first blocking dielectric layer. An opening is formed through a horizontal portion of the sacrificial liner. A horizontal portion of the first blocking dielectric layer at a bottom of the memory opening can be etched through the opening in the sacrificial liner. A semiconductor surface of the substrate can be physically exposed at a bottom of the memory opening with minimal overetch and/or surface damage. A second blocking dielectric layer can be formed, before or after formation of the sacrificial liner, to provide a multilayer blocking dielectric.
    Type: Grant
    Filed: October 21, 2014
    Date of Patent: April 5, 2016
    Assignee: SANDISK TECHNOLOGIES INC.
    Inventors: Masanori Tsutsumi, Hiroshi Sasaki, Hiroyuki Ogawa, Michiaki Sano, Masato Miyamoto, Kensuke Yamaguchi, Seiji Shimabukuro
  • Publication number: 20160093626
    Abstract: A method of making multi-level contacts includes providing an in-process multilevel device having a device region and a contact region including a stack of a plurality of alternating sacrificial layers and insulator layers located over a major surface of a substrate. A contact mask with at least one contact mask opening and at least one first terrace mask opening is provided over the stack, where the at least one first terrace mask opening is larger than the at least one contact mask opening. At least one first contact opening and at least one first terrace opening are simultaneously formed extending substantially perpendicular to the major surface of the substrate through the stack to a first sacrificial layer by etching a portion of the stack through the at least one contact mask opening and the at least one first terrace mask opening. A first electrically conductive via contact is deposited in the at least one first contact opening.
    Type: Application
    Filed: September 30, 2014
    Publication date: March 31, 2016
    Inventors: Keisuke Izumi, Michiaki Sano, Hiroshi Sasaki
  • Publication number: 20160093524
    Abstract: A method of making multi-level contacts includes providing an in-process multilevel device having a device region and a contact region including a stack of alternating sacrificial layers and insulating layers located over a major surface of a substrate. A contact mask having contact mask openings is provided over the stack, and a first over mask having first over mask openings is provided over the contact mask. A subset of the contact mask openings is substantially aligned with the first over mask openings. Contact openings are formed through the stack, wherein each of the contact openings extends substantially perpendicular to the major surface of the substrate to a respective one of the sacrificial layers. A plurality of electrically conductive via contacts is formed in the plurality of the contact openings.
    Type: Application
    Filed: September 30, 2014
    Publication date: March 31, 2016
    Inventors: Keisuke Izumi, Michiaki Sano, Hiroshi Sasaki
  • Publication number: 20160064281
    Abstract: Contact openings extending to sacrificial layers located at different depths can be formed by sequentially exposing a greater number of openings in a mask layer by iterative alternation of trimming of a slimming layer over the mask layer and an anisotropic etch that recesses pre-existing contact openings by one level. In one embodiment, pairs of an electrically conductive via contact and electrically conductive electrodes can be simultaneously formed as integrated line and via structures. In another embodiment, encapsulated unfilled cavities can be formed in the contact openings by non-conformal deposition of a material layer, electrically conductive electrodes can be formed by replacement of portions of the sacrificial layers, and the electrically conductive via contacts can be subsequently formed on the electrically conductive electrodes. Electrically conductive via contacts extending to electrically conductive electrodes located at different level can be provided with self-aligned insulating liner.
    Type: Application
    Filed: August 26, 2014
    Publication date: March 3, 2016
    Inventors: Keisuke Izumi, Naohito Yanagida, Michiaki Sano, Takehiro Yamazaki, Hiroaki Iuchi, Akio Yanai, Genta Mizuno, Minoru Yamaguchi