Patents by Inventor Tomoko Fujiwara

Tomoko Fujiwara 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: 20130062681
    Abstract: According to one embodiment, a semiconductor memory device includes a stacked body, a semiconductor pillar, an insulating film, and a charge storage film. The stacked body includes a plurality of electrode films stacked with an inter-layer insulating film provided between the electrode films. The semiconductor pillar pierces the stacked body. The insulating film is provided between the semiconductor pillar and the electrode films on an outer side of the semiconductor pillar with a gap interposed. The charge storage film is provided between the insulating film and the electrode films. The semiconductor pillar includes germanium. An upper end portion of the semiconductor pillar is supported by an interconnect provided above the stacked body.
    Type: Application
    Filed: March 8, 2012
    Publication date: March 14, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Jun Fujiki, Yoshiaki Fukuzumi, Hideaki Aochi, Tomoko Fujiwara
  • Publication number: 20130058163
    Abstract: According to one embodiment, a semiconductor memory device includes a stacked body, a semiconductor pillar, a charge storage layer, a tunneling layer, a dividing trench and a first heating unit. The stacked body includes a plurality of first insulating films stacked alternately with a plurality of electrode films. The semiconductor pillar pierces the stacked body. The charge storage layer is provided between the electrode films and the semiconductor pillar. The tunneling layer is provided between the charge storage layer and the semiconductor pillar. The dividing trench is provided between the semiconductor pillars in one direction orthogonal to a stacking direction of the stacked body to divide the electrode films. The first heating unit is provided in an interior of the dividing trench.
    Type: Application
    Filed: March 13, 2012
    Publication date: March 7, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Masaru KITO, Tomoko FUJIWARA, Hideaki AOCHI
  • Patent number: 8374033
    Abstract: A nonvolatile semiconductor memory device includes: a memory unit; and a control unit. The memory unit includes a multilayer structure including electrode films and inter-electrode insulating films alternately stacked in a first direction; a semiconductor pillar piercing the multilayer structure in the first direction; a memory layer provided between the semiconductor pillar and the electrode films; a inner insulating film provided between the memory layer and the semiconductor pillar; a outer insulating film provided between the memory layer and the electrode films; and a wiring electrically connected to the first semiconductor pillar. In erasing operation, the control unit sets the first wiring at a first potential and sets the electrode film at a second potential lower than the first potential, and then sets the first wiring at a third potential and sets the electrode film at a fourth potential higher than the third potential.
    Type: Grant
    Filed: March 22, 2010
    Date of Patent: February 12, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masaru Kito, Ryota Katsumata, Yoshiaki Fukuzumi, Masaru Kidoh, Hiroyasu Tanaka, Yosuke Komori, Megumi Ishiduki, Junya Matsunami, Tomoko Fujiwara, Hideaki Aochi, Ryouhei Kirisawa, Yoshimasa Mikajiri, Shigeto Oota
  • Patent number: 8361862
    Abstract: A method for manufacturing a nonvolatile semiconductor memory device, the device including a stacked structural unit including a plurality of insulating films alternately stacked with a plurality of electrode films in a first direction and a semiconductor pillar piercing the stacked structural unit in the first direction, the method includes: forming a stacked unit including a core material film alternately stacked with a sacrificial film on a major surface of a substrate perpendicular to the first direction; making a trench in the stacked unit, the trench extending in the first direction and a second direction in a plane perpendicular to the first direction; filling a filling material into the trench; removing the sacrificial film to form a hollow structural unit, the hollow structural unit including a post unit supporting the core material film on the substrate, the post unit being made of the filling material; and forming the stacked structural unit by stacking one of the insulating films and one of the el
    Type: Grant
    Filed: March 1, 2010
    Date of Patent: January 29, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki Fukuzumi, Ryota Katsumata, Masaru Kito, Masaru Kidoh, Hiroyasu Tanaka, Yosuke Komori, Megumi Ishiduki, Junya Matsunami, Tomoko Fujiwara, Hideaki Aochi, Ryouhei Kirisawa
  • Publication number: 20130021848
    Abstract: A memory cell comprises a first semiconductor layer, and a first conductive layer. The first semiconductor layer extends in a perpendicular direction with respect to a semiconductor substrate. The first conductive layer sandwiches a charge storage layer with the first semiconductor layer. A control circuit executes a first program operation and then executes a second program operation. The first program operation supplies a first voltage to the body of the memory cell and supplies a second voltage larger than the first voltage to the gate of the memory cell. The second program operation renders the body of the memory cell in a floating state and supplies a third voltage which is positive to the gate of the memory cell.
    Type: Application
    Filed: March 22, 2012
    Publication date: January 24, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Hitoshi IWAI, Tomoko Fujiwara, Hideaki Aochi, Masaru Kito
  • Publication number: 20130020627
    Abstract: In one embodiment, a shift register memory includes first and second control electrodes extending in a first direction parallel to a surface of a substrate, and facing each other in a second direction perpendicular to the first direction. The memory further includes a plurality of first floating electrodes provided in a line on a first control electrode side between the first and second control electrodes. The memory further includes a plurality of second floating electrodes provided in a line on a second control electrode side between the first and second control electrodes. Each of the first and second floating electrodes has a planar shape which is mirror-asymmetric with respect to a plane perpendicular to the first direction.
    Type: Application
    Filed: March 1, 2012
    Publication date: January 24, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki FUKUZUMI, Masaru KITO, Tomoko FUJIWARA, Kaori KAWASAKI, Hideaki AOCHI
  • Publication number: 20120241846
    Abstract: According to one embodiment, a nonvolatile semiconductor memory device comprises a first conductive layer, a second conductive layer, a first inter-electrode insulating film, and a third conductive layer stacked above the first conductive layer, a memory film, a semiconductor layer, an insulating member, and a silicide layer. The memory film and the semiconductor layer is formed on the inner surface of through hole provided in the second conductive layer, the first inter-electrode insulating film, and the third conductive layer. The insulating member is buried in a slit dividing the second conductive layer, the first inter-electrode insulating film, and the third conductive layer. The silicide layer is formed on surfaces of the second conductive layer and the third conductive layer in the slit. The distance between the second conductive layer and the third conductive layer along the inner surface of the slit is longer than that of along the stacking direction.
    Type: Application
    Filed: September 18, 2011
    Publication date: September 27, 2012
    Inventors: Kaori KAWASAKI, Yoshiaki Fukuzumi, Masaru Kito, Tomoko Fujiwara, Takeshi Imamura, Ryouhei Kirisawa, Hideaki Aochi
  • Patent number: 8264031
    Abstract: A nonvolatile semiconductor memory device includes: a semiconductor substrate; a multilayer structure; a semiconductor pillar; a third insulating film; and a fourth insulating film layer. The a multilayer structure is provided on the semiconductor substrate and including a plurality of constituent multilayer bodies stacked in a first direction perpendicular to a major surface of the semiconductor substrate. Each of the plurality of constituent multilayer bodies includes an electrode film provided parallel to the major surface, a first insulating film, a charge storage layer provided between the electrode film and the first insulating film, and a second insulating film provided between the charge storage layer and the electrode film. The semiconductor pillar penetrates through the multilayer structure in the first direction. The third insulating film is provided between the semiconductor pillar and the electrode film.
    Type: Grant
    Filed: January 29, 2010
    Date of Patent: September 11, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masaru Kidoh, Hiroyasu Tanaka, Tomoko Fujiwara, Megumi Ishiduki, Yosuke Komori, Masaru Kito, Yoshiaki Fukuzumi, Ryota Katsumata, Ryouhei Kirisawa, Junya Matsunami, Hideaki Aochi
  • Publication number: 20120195128
    Abstract: According to one embodiment, a nonvolatile semiconductor memory device includes a memory unit and a control unit. The memory unit includes a multilayer structure, a semiconductor pillar, a storage layer, an inner insulating film, an outer insulating film, a memory cell transistor. The control unit performs control of setting the thresholds of the memory transistor to either positive or negative, and performs control so that, with one of the thresholds most distant from 0 volts being defined as n-th threshold, width of distribution of m-th threshold (m being an integer of 1 or more smaller than n) having a sign being same as the n-th threshold is set narrower than width of distribution of the n-th threshold.
    Type: Application
    Filed: July 7, 2011
    Publication date: August 2, 2012
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Tomoko FUJIWARA, Masaru Kito, Yoshiaki Fukuzumi, Hideaki Aochi
  • Patent number: 8218358
    Abstract: According to one embodiment, a nonvolatile semiconductor memory device includes a substrate, a stacked body, a semiconductor pillar, a charge storage film, and a drive circuit. The stacked body is provided on the substrate. The stacked body includes a plurality of insulating films alternately stacked with a plurality of electrode films. A through-hole is made in the stacked body to align in a stacking direction. The semiconductor pillar is buried in an interior of the through-hole. The charge storage film is provided between the electrode film and the semiconductor pillar. The drive circuit supplies a potential to the electrode film. The diameter of the through-hole differs by a position in the stacking direction. The drive circuit supplies a potential to reduce a potential difference with the semiconductor pillar as a diameter of the through-hole piercing the electrode film decreases.
    Type: Grant
    Filed: August 5, 2010
    Date of Patent: July 10, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Ryota Katsumata, Hideaki Aochi, Hiroyasu Tanaka, Masaru Kito, Yoshiaki Fukuzumi, Masaru Kidoh, Yosuke Komori, Megumi Ishiduki, Junya Matsunami, Tomoko Fujiwara, Ryouhei Kirisawa, Yoshimasa Mikajiri, Shigeto Oota
  • Patent number: 8203884
    Abstract: A nonvolatile semiconductor memory device, includes: a stacked structural unit including electrode films alternately stacked with inter-electrode insulating films; a first and second semiconductor pillars piercing the stacked structural unit; a connection portion semiconductor layer to electrically connect the first and second semiconductor pillars; a connection portion conductive layer opposing the connection portion semiconductor layer; a memory layer, an inner insulating film, and an outer insulating film provided between the first and second semiconductor layers and the electrode films and between the connection portion semiconductor layer and the connection portion conductive layer. At least a portion of a face of the connection portion conductive layer opposing the outer insulating film is a curved surface having a recessed configuration on a side of the outer insulating film.
    Type: Grant
    Filed: March 19, 2010
    Date of Patent: June 19, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masaru Kito, Ryota Katsumata, Yoshiaki Fukuzumi, Masaru Kidoh, Hiroyasu Tanaka, Yosuke Komori, Megumi Ishiduki, Tomoko Fujiwara, Hideaki Aochi
  • Patent number: 8199573
    Abstract: A nonvolatile semiconductor memory device comprises: a bit line; a source line; a memory string having a plurality of electrically data-rewritable memory transistors connected in series; a first select transistor provided between one end of the memory string and the bit line; a second select transistor provided between the other end of the memory string and the source line; and a control circuit configured to control a read operation. A plurality of the memory strings connected to one bit line via a plurality of the first select transistors. During reading of data from a selected one of the memory strings, the control circuit renders conductive the first select transistor connected to an unselected one of the memory strings and renders non-conductive the second select transistor connected to unselected one of the memory strings.
    Type: Grant
    Filed: January 27, 2010
    Date of Patent: June 12, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki Fukuzumi, Ryota Katsumata, Masaru Kito, Masaru Kidoh, Hiroyasu Tanaka, Tomoko Fujiwara, Megumi Ishiduki, Yosuke Komori, Yoshimasa Mikajiri, Shigeto Oota, Ryouhei Kirisawa, Hideaki Aochi
  • Publication number: 20120132981
    Abstract: According to one embodiment, a columnar semiconductor, a floating gate electrode formed on a side surface of the columnar semiconductor via a tunnel dielectric film, and a control gate electrode formed to surround the floating gate electrode via a block dielectric film are provided.
    Type: Application
    Filed: May 20, 2011
    Publication date: May 31, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Takeshi Imamura, Yoshiaki Fukuzumi, Hideaki Aochi, Masaru Kito, Tomoko Fujiwara, Kaori Kawasaki, Ryouhei Kirisawa
  • Patent number: 8188530
    Abstract: A semiconductor memory device provided with a cell array section and a peripheral circuit section, the device includes: a back gate electrode; a stacked body provided on the back gate electrode; a plurality of semiconductor pillars extending in a stacking direction; connection members, each of the connection members connecting one of the semiconductor pillars to another one of the semiconductor pillars; a back-gate electrode contact applying a potential to the back gate electrode; a gate electrode provided in the peripheral circuit section; and a gate electrode contact applying a potential to the gate electrode, the back gate electrode and the gate electrode respectively including: a lower semiconductor layer; a conductive layer provided on the lower semiconductor layer; and an upper semiconductor layer provided on the conductive layer, the connection members being provided in or on the upper semiconductor layer, the back-gate electrode contact and the gate electrode contact being in contact with the conducti
    Type: Grant
    Filed: March 22, 2010
    Date of Patent: May 29, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroyasu Tanaka, Ryota Katsumata, Hideaki Aochi, Masaru Kito, Yoshiaki Fukuzumi, Masaru Kidoh, Yosuke Komori, Megumi Ishiduki, Junya Matsunami, Tomoko Fujiwara, Ryouhei Kirisawa, Yoshimasa Mikajiri, Shigeto Oota
  • Patent number: 8189371
    Abstract: According to one embodiment, a nonvolatile semiconductor memory device includes a memory cell array and a control circuit. The memory cell array includes a stacked body, a through-hole, a semiconductor pillar, and a charge storage film. The stacked body includes a plurality of insulating films alternately stacked with a plurality of electrode films. The through-hole is made in the stacked body to align in a stacking direction. The semiconductor pillar is buried in the through-hole. The charge storage film is provided between the electrode films and the semiconductor pillar. Memory cells are formed at each intersection between the electrode films and the semiconductor pillar.
    Type: Grant
    Filed: August 5, 2010
    Date of Patent: May 29, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Ryota Katsumata, Hideaki Aochi, Hiroyasu Tanaka, Masaru Kito, Yoshiaki Fukuzumi, Masaru Kidoh, Yosuke Komori, Megumi Ishiduki, Junya Matsunami, Tomoko Fujiwara, Ryouhei Kirisawa, Yoshimasa Mikajiri, Shigeto Oota
  • Patent number: 8178919
    Abstract: A nonvolatile semiconductor memory device, includes: a stacked structural unit including electrode films alternately stacked with inter-electrode insulating films; first and second semiconductor pillars piercing the stacked structural unit; a connection portion semiconductor layer electrically connect the first and second semiconductor pillars; a connection portion conductive layer provided to oppose the connection portion semiconductor layer; a memory layer and an inner insulating film provided between the first and semiconductor pillars and each of the electrode films, and between the connection portion conductive layer and the connection portion semiconductor layer; an outer insulating film provided between the memory layer and each of the electrode films; and a connection portion outer insulating film provided between the memory layer and the connection portion conductive layer. The connection portion outer insulating film has a film thickness thicker than a film thickness of the outer insulating film.
    Type: Grant
    Filed: March 19, 2010
    Date of Patent: May 15, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomoko Fujiwara, Ryota Katsumata, Masaru Kito, Yoshiaki Fukuzumi, Masaru Kidoh, Hiroyasu Tanaka, Yosuke Komori, Megumi Ishiduki, Junya Matsunami, Hideaki Aochi, Ryouhei Kirisawa, Yoshimasa Mikajiri, Shigeto Oota
  • Patent number: 8169826
    Abstract: A nonvolatile semiconductor memory device comprises: a plurality of first memory strings; a first select transistor having one end thereof connected to one end of the first memory strings; a first line commonly connected to the other end of a plurality of the first select transistors; a switch circuit having one end thereof connected to the first line; and a second line commonly connected to the other end of a plurality of the switch circuits. The switch circuit controls electrical connection between the second line and the first line.
    Type: Grant
    Filed: March 18, 2010
    Date of Patent: May 1, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomoo Hishida, Yoshihisa Iwata, Megumi Ishiduki, Ryota Katsumata, Yoshiaki Fukuzumi, Masaru Kito, Masaru Kidoh, Hiroyasu Tanaka, Yosuke Komori, Junya Matsunami, Tomoko Fujiwara, Hideaki Aochi, Ryouhei Kirisawa, Yoshimasa Mikajiri, Shigeto Oota
  • Publication number: 20120026775
    Abstract: According to one embodiment, a method of operating a semiconductor memory device is disclosed. The method can include storing read-only data in at least one selected from a memory cell of an uppermost layer and a memory cell of a lowermost layer of a plurality of memory cells connected in series via a channel body. The channel body extends upward from a substrate to intersect a plurality of electrode layers stacked on the substrate. The method can include prohibiting a data erase operation of the read-only memory cell having the read-only data stored in the read-only memory cell.
    Type: Application
    Filed: March 21, 2011
    Publication date: February 2, 2012
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Kunihiro Yamada, Hideaki Aochi, Masaru Kito, Tomoko Fujiwara, Yoshiaki Fukuzumi, Ryouhei Kirisawa, Yoshimasa Mikajiri, Kaori Kawasaki
  • Publication number: 20110188321
    Abstract: According to one embodiment, a nonvolatile semiconductor memory device includes a memory unit and a control unit. The memory unit includes a charge storage film, a first insulating film provided adjacent to one surface of the charge storage film, a second insulating film provided adjacent to one other surface of the charge storage film, a semiconductor portion provided adjacent to the first insulating film and a plurality of electrode portions provided adjacent to the second insulating film. The control unit performs a control of applying a first voltage to electrode portions adjacent to each other in one direction at different timing respectively, in an erasing. The erasing is performed by at least one selected from injecting electron holes into the charge storage film and removing electrons from the charge storage film. The first voltage is applied from one of the electrode portions to the charge storage film to be erased.
    Type: Application
    Filed: February 1, 2011
    Publication date: August 4, 2011
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Masaru Kito, Tomoko Fujiwara, Yoshimasa Mikajiri
  • Publication number: 20110103149
    Abstract: According to one embodiment, a nonvolatile semiconductor memory device includes a memory cell array and a control circuit. The memory cell array includes a stacked body, a through-hole, a semiconductor pillar, and a charge storage film. The stacked body includes a plurality of insulating films alternately stacked with a plurality of electrode films. The through-hole is made in the stacked body to align in a stacking direction. The semiconductor pillar is buried in the through-hole. The charge storage film is provided between the electrode films and the semiconductor pillar. Memory cells are formed at each intersection between the electrode films and the semiconductor pillar.
    Type: Application
    Filed: August 5, 2010
    Publication date: May 5, 2011
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Ryota KATSUMATA, Hideaki Aochi, Hiroyasu Tanaka, Masaru Kito, Yoshiaki Fukuzumi, Masaru Kidoh, Yosuke Komori, Megumi Ishiduki, Junya Matsunami, Tomoko Fujiwara, Ryouhei Kirisawa, Yoshimasa Mikajiri, Shigeto Oota