Patents by Inventor Tohru Ozaki

Tohru Ozaki 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: 8476693
    Abstract: In one embodiment, a nonvolatile semiconductor memory includes a memory cell array, a first silicon nitride film and a second silicon nitride film. The memory cell array includes NAND cell units. Each of the NAND cell units has memory cell transistors, a source-side select gate transistor and a drain-side select gate transistor. The source-side select gate transistors is disposed in such a manner as to face each other and the drain-side select gate transistors is disposed in such a manner as to face each other. The first silicon nitride film is present in a region between the source-side select gate transistors and is disposed at a position lowest from the upper surface of the semiconductor substrate. The second silicon nitride film is formed in a region between the drain-side select gate transistors and is disposed at a position lowest from the upper surface of the semiconductor substrate.
    Type: Grant
    Filed: March 17, 2011
    Date of Patent: July 2, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takayuki Toba, Tohru Ozaki
  • Publication number: 20130049098
    Abstract: In one embodiment, a nonvolatile semiconductor memory device includes a substrate, and a plurality of cell transistors, each of which includes a first insulating layer, a charge storage layer, a second insulating layer, and a control electrode successively provided on the substrate, side surfaces of the charge storage layer including inclined surfaces. The device further includes at least one insulator including a first insulator part provided on side surfaces of the cell transistors and on a top surface of the semiconductor substrate between the cell transistors, and a second insulator part continuously provided on an air gap between the cell transistors and on the cell transistors. A first distance from the top surface of the semiconductor substrate between the cell transistors to a bottom end of the air gap is greater than a thickness of the at least one insulator provided on the side surfaces of the cell transistors.
    Type: Application
    Filed: March 6, 2012
    Publication date: February 28, 2013
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tatsuo IZUMI, Tohru Ozaki
  • Patent number: 8362533
    Abstract: According to an aspect of the present invention, there is provided a semiconductor device including: a transistor including: a source, a drain and a gate; first and second plugs on the source and the drain; a third plug on the gate to have a top face higher than that of the first plug; an interlayer insulating film covering the transistor and the first to the third plugs; a ferroelectric capacitor on the interlayer insulating film, one electrode thereof being connected to the first plug; a barrier film covering surfaces of the ferroelectric capacitor and the interlayer insulating film to prevent a substance affecting the ferroelectric capacitor from entering therethrough; and fourth and fifth plugs disposed on the second and the third plugs and connected thereto through connection holes formed in the barrier film.
    Type: Grant
    Filed: August 26, 2010
    Date of Patent: January 29, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Tohru Ozaki
  • Patent number: 8283791
    Abstract: According to one embodiment, a semiconductor device includes a plurality of first interconnects, a second interconnect, a third interconnect, and a plurality of conductive members. The plurality of first interconnects are arranged periodically to extend in one direction. The second interconnect is disposed outside a group of the plurality of first interconnects to extend in the one direction. The third interconnect is provided between the group and the second interconnect. The plurality of conductive members are disposed on a side opposite to the group as viewed from the second interconnect. A shortest distance between the first interconnect and the third interconnect, a shortest distance between the third interconnect and the second interconnect, and a shortest distance between the first interconnects are equal. A shortest distance between the second interconnect and the conductive member is longer than the shortest distance between the first interconnects.
    Type: Grant
    Filed: March 18, 2011
    Date of Patent: October 9, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takayuki Toba, Tohru Ozaki, Toshiki Hisada, Hiromitsu Mashita, Takafumi Taguchi
  • Publication number: 20120139024
    Abstract: In one embodiment, a nonvolatile semiconductor memory includes a memory cell array, a first silicon nitride film and a second silicon nitride film. The memory cell array includes NAND cell units. Each of the NAND cell units has memory cell transistors, a source-side select gate transistor and a drain-side select gate transistor. The source-side select gate transistors is disposed in such a manner as to face each other and the drain-side select gate transistors is disposed in such a manner as to face each other. The first silicon nitride film is present in a region between the source-side select gate transistors and is disposed at a position lowest from the upper surface of the semiconductor substrate. The second silicon nitride film is formed in a region between the drain-side select gate transistors and is disposed at a position lowest from the upper surface of the semiconductor substrate.
    Type: Application
    Filed: March 17, 2011
    Publication date: June 7, 2012
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Takayuki TOBA, Tohru Ozaki
  • Publication number: 20120106252
    Abstract: A nonvolatile semiconductor memory device includes a first region, a second region, and a plurality of word lines. The first region includes a plurality of electrically-rewritable memory transistors. The second region is located around the first region. The plurality of word lines are connected to the gates of the plurality of memory transistors respectively. The plurality of word lines includes interconnection portions and connection portions respectively. The interconnection portions extend in a first direction to head from the first region to the second region and are arrayed in a second direction orthogonal to the first direction with a first distance therebetween. The connection portions are extending from the interconnection portions, located in the second region, and electrically connected to contacts, respectively. The ends of the plurality of connection portions are formed along straight lines extending in the second direction.
    Type: Application
    Filed: October 27, 2011
    Publication date: May 3, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tohru OZAKI, Mitsuhiro NOGUCHI
  • Publication number: 20120020158
    Abstract: A memory cell array includes memory strings arranged in a first direction. Word-lines and select gate lines extend in a second direction perpendicular to the first direction. The select gate line also extends in the second direction. The word-lines have a first line width in the first direction and arranged with a first distance therebetween. The select gate line includes a first interconnection in the first direction, the first interconnection having a second line width larger than the first line width, and a second interconnection extending from an end portion of the first interconnection, the second interconnection having a third line width the same as the first line width. A first word-line adjacent to the select gate line is arranged having a second distance to the second interconnection, the second distance being (4N+1) times the first distance (N being an integer of 1 or more).
    Type: Application
    Filed: July 20, 2011
    Publication date: January 26, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tohru OZAKI, Mitsuhiro Noguchi, Hideaki Maekawa, Hiromitsu Mashita, Takafumi Taguchi, Kazuhito Kobayashi, Hidefumi Mukai, Hiroyuki Nitta
  • Publication number: 20120001331
    Abstract: According to one embodiment, a semiconductor device includes a plurality of first interconnects, a second interconnect, a third interconnect, and a plurality of conductive members. The plurality of first interconnects are arranged periodically to extend in one direction. The second interconnect is disposed outside a group of the plurality of first interconnects to extend in the one direction. The third interconnect is provided between the group and the second interconnect. The plurality of conductive members are disposed on a side opposite to the group as viewed from the second interconnect. A shortest distance between the first interconnect and the third interconnect, a shortest distance between the third interconnect and the second interconnect, and a shortest distance between the first interconnects are equal. A shortest distance between the second interconnect and the conductive member is longer than the shortest distance between the first interconnects.
    Type: Application
    Filed: March 18, 2011
    Publication date: January 5, 2012
    Applicant: Kabushi Kaisha Toshiba
    Inventors: Takayuki Toba, Tohru Ozaki, Toshiki Hisada, Hiromitsu Mashita, Takafumi Taguchi
  • Publication number: 20110031544
    Abstract: According to an aspect of the present invention, there is provided a semiconductor apparatus including: a semiconductor substrate; an element isolation region formed in the semiconductor substrate so as to extend in a first direction; a gate electrode formed in the semiconductor substrate so as to extend in a second direction crossing the first direction and to penetrate through the element isolation region; a gate insulating film interposed between the gate electrode and the semiconductor substrate; an interlayer dielectric film formed on the gate electrode; a ferroelectric capacitor including: first and second electrodes disposed on the interlayer dielectric film and a ferroelectric between the first and second electrodes; and first and second semiconductor pillars being in contact respectively with the first and second electrodes.
    Type: Application
    Filed: October 6, 2010
    Publication date: February 10, 2011
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Tohru OZAKI
  • Publication number: 20100320518
    Abstract: According to an aspect of the present invention, there is provided a semiconductor device including: a transistor including: a source, a drain and a gate; first and second plugs on the source and the drain; a third plug on the gate to have a top face higher than that of the first plug; an interlayer insulating film covering the transistor and the first to the third plugs; a ferroelectric capacitor on the interlayer insulating film, one electrode thereof being connected to the first plug; a barrier film covering surfaces of the ferroelectric capacitor and the interlayer insulating film to prevent a substance affecting the ferroelectric capacitor from entering therethrough; and fourth and fifth plugs disposed on the second and the third plugs and connected thereto through connection holes formed in the barrier film.
    Type: Application
    Filed: August 26, 2010
    Publication date: December 23, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Tohru Ozaki
  • Patent number: 7821047
    Abstract: According to an aspect of the present invention, there is provided a semiconductor apparatus including: a semiconductor substrate; an element isolation region formed in the semiconductor substrate so as to extend in a first direction; a gate electrode formed in the semiconductor substrate so as to extend in a second direction crossing the first direction and to penetrate through the element isolation region; a gate insulating film interposed between the gate electrode and the semiconductor substrate; an interlayer dielectric film formed on the gate electrode; a ferroelectric capacitor including: first and second electrodes disposed on the interlayer dielectric film and a ferroelectric between the first and second electrodes; and first and second semiconductor pillars being in contact respectively with the first and second electrodes.
    Type: Grant
    Filed: September 27, 2007
    Date of Patent: October 26, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Tohru Ozaki
  • Patent number: 7816717
    Abstract: A semiconductor memory device, comprising: a semiconductor substrate; a memory cell section comprising a memory transistor provided on the semiconductor substrate, the memory transistor including a first gate electrode provided on the semiconductor substrate with a gate insulating film interposed therebetween, and a source and drain provided at both sides of the first gate electrode on the semiconductor substrate, and a ferroelectric capacitor provided above the memory transistor, the ferroelectric capacitor including a first electrode film connected to any one of a source and drain of the memory transistor, a second electrode film connected to the other one of the drain and source of the memory transistor, and a ferroelectric film provided between the first electrode film and the second electrode film, the memory cell section having the memory transistor and the ferroelectric capacitor connected in parallel to each other; and a select transistor section, comprising a select transistor provided at an end of t
    Type: Grant
    Filed: January 25, 2008
    Date of Patent: October 19, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Tohru Ozaki
  • Patent number: 7812384
    Abstract: According to an aspect of the present invention, there is provided a semiconductor device including: a transistor including: a source, a drain and a gate; first and second plugs on the source and the drain; a third plug on the gate to have a top face higher than that of the first plug; an interlayer insulating film covering the transistor and the first to the third plugs; a ferroelectric capacitor on the interlayer insulating film, one electrode thereof being connected to the first plug; a barrier film covering surfaces of the ferroelectric capacitor and the interlayer insulating film to prevent a substance affecting the ferroelectric capacitor from entering therethrough; and fourth and fifth plugs disposed on the second and the third plugs and connected thereto through connection holes formed in the barrier film.
    Type: Grant
    Filed: April 25, 2008
    Date of Patent: October 12, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Tohru Ozaki
  • Publication number: 20100193849
    Abstract: According to one embodiment, a semiconductor memory device having a ferroelectric film, includes a semiconductor substrate, a field effect transistor formed on the semiconductor substrate, an inter-layer insulating film formed on the field effect transistor and the semiconductor substrate, a plug constituted with a single-crystalline structure, the plug being formed in the inter-layer insulating film and being connected with a source or a drain of the field effect transistor, a lower electrode constituted with a single-crystalline structure formed on the plug, a ferroelectric film formed on the lower electrode an upper electrode formed on the ferroelectric film.
    Type: Application
    Filed: January 18, 2010
    Publication date: August 5, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Jun NISHIMURA, Yoshinori KUMURA, Hiroyuki KANAYA, Tohru OZAKI
  • Patent number: 7763920
    Abstract: According to an aspect of the present invention, there is provided a semiconductor memory including a lower electrode, a first insulating region formed in the same layer as the lower electrode, a ferroelectric film formed on the lower electrode and on the first insulating region, an upper electrode formed on the ferroelectric film, a second insulating region formed in the same layer as the upper electrode and a transistor. The first insulating region partitions the lower electrode. The second insulating region partitions the upper electrode. The transistor includes a first impurity region connected to the lower electrode and a second impurity region connected to the upper electrode. At least one of the first insulating region and the second insulating region is formed by insulating the lower electrode or the upper electrode.
    Type: Grant
    Filed: September 11, 2007
    Date of Patent: July 27, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshinori Kumura, Tohru Ozaki, Iwao Kunishima
  • Publication number: 20100163943
    Abstract: A memory includes a first interlayer on transistors; a first and second plugs connected to the transistor; ferroelectric capacitors; a second interlayer covering a side surface of the capacitor; a local interconnection connecting the second plug to the upper electrode, wherein two upper electrodes adjacent to each other on the second plug are connected to the second plug, the lower electrodes adjacent to each other on the first plug are connected to the first plug, cell blocks comprising the connected capacitors are arranged, cell blocks adjacent to each other are arranged to be shifted by a half pitch of the local interconnection, a first gap between two capacitors adjacent to each other on the second plug is larger than twice a thickness of the second interlayer, and a second gap between the cell blocks adjacent to each other is smaller than twice the thickness of the second interlayer.
    Type: Application
    Filed: September 14, 2009
    Publication date: July 1, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Tohru Ozaki
  • Publication number: 20100123177
    Abstract: According to an aspect of the present invention, there is provided a semiconductor memory device, including a TC unit series-type FeRAM in which a plurality of memory cells, each of the memory cells comprising a memory transistor and a ferroelectric capacitor connected each other in parallel, are serially connected, including, a first electrode over and electrically connected to one of a source and a drain in the memory transistor, a second electrode opposed to the first electrode over and electrically connected to the other of the source and the drain in the memory transistor, a third electrode on both sidewalls of the second electrode other than an under portion of the second electrode, and a ferroelectric film between the first electrode and the two electrodes, the second electrode and the third electrode, wherein the ferroelectric capacitor comprises the first and the third electrode, and the ferroelectric film.
    Type: Application
    Filed: November 17, 2009
    Publication date: May 20, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Tohru OZAKI
  • Publication number: 20100117128
    Abstract: A semiconductor memory device has a semiconductor substrate, an impurity diffusion layer that is formed at a surface portion of the semiconductor substrate, an interlayer insulating film that is formed on the semiconductor substrate, a contact plug that penetrates the interlayer insulating film, has a top surface formed higher than a top surface of the interlayer insulating film, a region having a convex shape formed higher than the top surface of the interlayer insulating film, and contacts the impurity diffusion layer, a lower capacitor electrode film that is formed on the contact plug and a predetermined region of the interlayer insulating film, a ferroelectric film that is formed on the lower capacitor electrode film, and an upper capacitor electrode film that is formed on the ferroelectric film.
    Type: Application
    Filed: September 22, 2009
    Publication date: May 13, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Saku Hashiura, Yoshinori Kumura, Tohru Ozaki
  • Publication number: 20100072525
    Abstract: According to a method for manufacturing a semiconductor memory device of the present invention, a capacitor lower electrode film is left on the wiring layer located above a dummy transistor. In this manner, when processing of the capacitors is performed by removing a capacitor upper electrode film and a ferroelectric film, removal of the wiring layer can be prevented, and the connection between the diffusion layer of a select transistor and a bit line can be secured.
    Type: Application
    Filed: September 3, 2009
    Publication date: March 25, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshiro Shimojo, Tohru Ozaki, Yoshinori Kumura
  • Publication number: 20100072527
    Abstract: A semiconductor memory device includes: a transistor on a semiconductor substrate; an interlayer dielectric film covering the transistor; a ferroelectric capacitor comprising a first upper electrode, a ferroelectric film, and a lower electrode on the interlayer dielectric film; a contact plug which is in the interlayer dielectric film and electrically connects the lower electrode to the transistor; a second upper electrode on the first upper electrode, a side surface of the second upper electrode being formed in a forward tapered shape; and an interconnection electrically connected via the second upper electrode to the first upper electrode.
    Type: Application
    Filed: September 14, 2009
    Publication date: March 25, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Tohru OZAKI