Patents by Inventor Hiroyuki Nagashima
Hiroyuki Nagashima 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).
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Patent number: 8964447Abstract: A nonvolatile semiconductor memory device comprises a cell array including a plurality of first lines, a plurality of second lines intersecting the plurality of first lines, and a plurality of memory cells arranged in matrix and connected at intersections of the first and second lines between both lines, each memory cell containing a serial circuit of an electrically erasable programmable variable resistive element of which resistance is nonvolatilely stored as data and a non-ohmic element; and a plurality of access circuits operative to simultaneously access the memory cells physically separated from each other in the cell array.Type: GrantFiled: June 24, 2009Date of Patent: February 24, 2015Assignee: Kabushiki Kaisha ToshibaInventors: Hiroyuki Nagashima, Hirofumi Inoue
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Patent number: 8929140Abstract: According to one embodiment, a memory system includes a nonvolatile semiconductor memory device, a voltage generation unit and a control unit. The nonvolatile semiconductor memory device includes a memory cell array having a plurality of blocks each including a plurality of memory cells, and a voltage generation unit configured to change a read level of the memory cell. The control unit controls write, read, and erase of the nonvolatile semiconductor memory device. The control unit changes the read level between a start of use of the nonvolatile semiconductor memory device and a timing after an elapse of a time.Type: GrantFiled: May 2, 2012Date of Patent: January 6, 2015Assignee: Kabushiki Kaisha ToshibaInventor: Hiroyuki Nagashima
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Publication number: 20140376302Abstract: A nonvolatile semiconductor memory device comprises a cell array including plural MATs (unit cell arrays) arranged in matrix, each MAT containing a plurality of first lines, a plurality of second lines intersecting the plurality of first lines, and a plurality of memory cells connected at intersections of the first and second lines between both lines, each memory cell containing an electrically erasable programmable variable resistive element of which resistance is nonvolatilely stored as data; and a plurality of write/erase circuits connected to the MATs and operative to execute data write or erase to the memory cells inside the MATs in accordance with input data. A part of the plurality of write/erase circuits writes data to memory cells inside a corresponding MAT while another part of the plurality of write/erase circuits erases data from memory cells inside a corresponding MAT at the same time.Type: ApplicationFiled: September 8, 2014Publication date: December 25, 2014Applicant: KABUSHIKI KAISHA TOSHIBAInventors: Hiroyuki NAGASHIMA, Hirofumi INOUE
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Patent number: 8891304Abstract: According to one embodiment, a nonvolatile semiconductor memory device includes a memory cell array includes blocks, each of the blocks includes NAND strings that each comprise memory cells serially connected in a first direction, word lines respectively connected to memory cell groups arranged in a second direction in the block, and a controller configured to perform a process (A) of verifying one of states in which all of the memory cells included in the block are turned on (pass) and at least one memory cell is turned off (fail) by use of a first read voltage applied to unselected word lines in a data read time, and to perform a process (B) of reading data from the fail block by use of a second read voltage that is higher than the first read voltage and applied to the unselected word lines.Type: GrantFiled: March 3, 2011Date of Patent: November 18, 2014Assignee: Kabushiki Kaisha ToshibaInventor: Hiroyuki Nagashima
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Patent number: 8842481Abstract: A nonvolatile semiconductor memory device includes a cell array including plural MATs (unit cell arrays) arranged in matrix, each MAT containing a plurality of first lines, a plurality of second lines intersecting the plurality of first lines, and a plurality of memory cells connected at intersections of the first and second lines between both lines, each memory cell containing an electrically erasable programmable variable resistive element of which resistance is nonvolatilely stored as data; and a plurality of write/erase circuits connected to the MATs and operative to execute data write or erase to the memory cells inside the MATs in accordance with input data. A part of the plurality of write/erase circuits writes data to memory cells inside a corresponding MAT while another part of the plurality of write/erase circuits erases data from memory cells inside a corresponding MAT at the same time.Type: GrantFiled: February 15, 2013Date of Patent: September 23, 2014Assignee: Kabushiki Kaisha ToshibaInventors: Hiroyuki Nagashima, Hirofumi Inoue
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Publication number: 20140247669Abstract: According to one embodiment, there is provided a memory system including a non-volatile memory device, a monitoring unit, and a changing unit. The non-volatile memory device stores data. The monitoring unit monitors a characteristic of the non-volatile memory device when writing and erasing processes are performed to write and erase the data to and from the non-volatile memory device. The changing unit changes at least one of a value of a writing start voltage and an increase width of a writing voltage in the writing process in accordance with the monitored characteristic so that a time for the writing process is substantially identical to a target value. The writing process is a process in which a writing operation and a verification operation are alternately repeated.Type: ApplicationFiled: May 13, 2014Publication date: September 4, 2014Applicant: KABUSHIKI KAISHA TOSHIBAInventor: Hiroyuki NAGASHIMA
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Patent number: 8817552Abstract: A semiconductor memory device comprises a plurality of memory layers arranged in multilayer, each memory layer including a cell array, the cell array containing a plurality of first parallel lines, a plurality of second parallel lines arranged crossing the first lines, and a plurality of memory cells connected at intersections of the first lines and the second lines; a pulse generator operative to generate pulses required for data access to the memory cell; and a control means operative to control the pulse generator such that the pulse output from the pulse generator has energy in accordance with the memory layer to which the access target memory cell belongs.Type: GrantFiled: April 16, 2013Date of Patent: August 26, 2014Assignee: Kabushiki Kaisha ToshibaInventors: Hiroyuki Nagashima, Naoya Tokiwa
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Patent number: 8792278Abstract: A non-volatile semiconductor memory device includes: a cell array including a plurality of first wirings, a plurality of second wirings that intersects the plurality of first wirings, and memory cells that are formed at intersections of the first wirings and the second wirings and are connected between the first and second wirings; a first contact plug that comes into contact with a side portion of the first wiring provided at a first position and extends to the first wiring provided at a second position higher than the first position in a laminated direction; and a second contact plug that comes into contact with a side portion of the second wiring provided at a third position between the first position and the second position and extends to the second wiring provided at a fourth position higher than the second position in the laminated direction.Type: GrantFiled: December 17, 2012Date of Patent: July 29, 2014Assignee: Kabushiki Kaisha ToshibaInventor: Hiroyuki Nagashima
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Patent number: 8755233Abstract: According to one embodiment, there is provided memory system including a non-volatile memory device, a monitoring unit, and a changing unit. The non-volatile memory device stores data. The monitoring unit monitors a characteristic of the non-volatile memory device when writing and erasing processes are performed to write and erase the data to and from the non-volatile memory device. The changing unit changes at least one of a value of a writing start voltage and an increase width of a writing voltage in the writing process in accordance with the monitored characteristic so that a time for the writing process is substantially identical to a target value. The writing process is a process in which a writing operation and a verification operation are alternately repeated.Type: GrantFiled: September 22, 2011Date of Patent: June 17, 2014Assignee: Kabushiki Kaisha ToshibaInventor: Hiroyuki Nagashima
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Publication number: 20140063943Abstract: According to one embodiment, a memory system includes a semiconductor memory including a memory core having first and second circuits and an input/output circuit, a control device, a voltage control circuit which generates first to third drive voltages, and the first to third power supply lines separated from each other. The voltage control circuit supplies the first drive voltage to the first circuit through the first power supply line, the second drive voltage lower than the first drive voltage to the input/output circuit and the control device through the second power supply line, and the third drive voltage to the second circuit through the third power supply line.Type: ApplicationFiled: September 4, 2013Publication date: March 6, 2014Inventor: Hiroyuki NAGASHIMA
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Patent number: 8655254Abstract: A lubricant applicator includes: a lubricant application unit that is arranged so as to be in contact with a surface of an image carrier, scrapes a solid lubricant, and applies the solid lubricant onto the surface of the image carrier while moving a surface of the lubricant application unit; a lubricant holding member that holds the solid lubricant; and a lubricant biasing unit that biases the solid lubricant against the lubricant application unit. The lubricant biasing unit is housed in a housing under a state that one end of the lubricant biasing unit is held by the lubricant holding member so that a position of the one end of the lubricant biasing unit is restricted, and another end of the lubricant biasing unit is held by a biasing-unit holding member that is provided to restrict a position of the another end of the lubricant biasing unit.Type: GrantFiled: September 16, 2010Date of Patent: February 18, 2014Assignee: Ricoh Company, LimitedInventors: Yuji Arai, Ken Amemiya, Toshio Koike, Michiya Okamoto, Takuma Iwasaki, Hiroyuki Nagashima, Fumihito Itoh, Hiroshi Ono, Masahiko Shakuto, Kaoru Yoshino, Satoshi Hatori, Yuta Azeyanagi
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Patent number: 8644072Abstract: There is provided a semiconductor memory device having a plurality of memory cell layers which can be used even if part of the memory cell layers is determined as defective.Type: GrantFiled: December 22, 2008Date of Patent: February 4, 2014Assignee: Kabushiki Kaisha ToshibaInventor: Hiroyuki Nagashima
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Patent number: 8612824Abstract: A semiconductor memory device includes: plural semiconductor memory chips to store information depending on an amount of accumulated charge; plural parameter storage units provided in correspondence with the semiconductor memory chips, each parameter to store therein a parameter that defines an electrical characteristic of a signal used for writing information into or reading information from a corresponding one of the semiconductor memory chips; an error correction encoding unit configured to generate a first correction code capable of correcting an error in the information stored in a number of semiconductor memory chips no greater than a predetermined number out of the semiconductor memory chips, from the information stored in the semiconductor memory chips; and a parameter processing unit configured to change the parameters respectively corresponding to the number of semiconductor memory chips no greater than the predetermined number, and write the parameters changed into the parameter storage units, respType: GrantFiled: March 2, 2011Date of Patent: December 17, 2013Assignee: Kabushiki Kaisha ToshibaInventors: Kazumasa Yamamoto, Shinichi Kanno, Shigehiro Asano, Hiroyuki Nagashima
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Patent number: 8575590Abstract: According to one embodiment, there is provided a nonvolatile semiconductor memory device including a first interconnection layer, memory cell modules each of which is formed by laminating a non-ohmic element layer with an MIM structure having an insulating film sandwiched between metal films and a variable resistance element layer, and a second interconnection layer formed on the memory cell modules, the insulating film of the non-ohmic element layer includes plural layers whose electron barriers and dielectric constants are different, or contains impurity atoms that form defect levels in the insulating film or contains semiconductor or metal dots. The nonvolatile semiconductor memory device using non-ohmic elements and variable resistance elements in which memory cells can be miniaturized and formed at low temperatures is realized by utilizing the above structures.Type: GrantFiled: March 2, 2011Date of Patent: November 5, 2013Assignee: Kabushiki Kaisha ToshibaInventors: Koichi Muraoka, Hiroyuki Nagashima
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Patent number: 8575589Abstract: A nonvolatile semiconductor memory device includes a plurality of first lines; a plurality of second lines crossing the plurality of first lines; a plurality of memory cells each connected at an intersection of the first and second lines between both lines and including a variable resistor operative to store information in accordance with a variation in resistance; and a protection film covering the side of the variable resistor to suppress migration of cations at the side of the variable resistor.Type: GrantFiled: November 14, 2008Date of Patent: November 5, 2013Assignee: Kabushiki Kaisha ToshibaInventors: Hiroyuki Nagashima, Koichi Kubo, Hirofumi Inoue
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Patent number: 8565661Abstract: A cleaning device that can be incorporated in an image forming apparatus which includes an image carrier configured to form a toner image, and a cleaning device configured to clean residual toner on the surface of the image carrier. The cleaning device includes a cleaning blade having a blade member provided to contact the surface of the image carrier and a holder to hold the blade member. The cleaning device further includes a frame to hold the cleaning blade and a vibration suppression member provided across the cleaning blade and the frame to couple the cleaning blade and the frame together and suppress vibration.Type: GrantFiled: September 21, 2009Date of Patent: October 22, 2013Assignee: Ricoh Company, Ltd.Inventors: Michiya Okamoto, Hiroyuki Nagashima, Fumihito Itoh, Hiroshi Ono, Ken Amemiya, Masahiko Shakuto, Toshio Koike, Yuji Arai, Kaoru Yoshino, Takuma Iwasaki
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Patent number: 8507889Abstract: A nonvolatile semiconductor memory device includes a memory cell array where a plurality of memory cell layers having a plurality of first and second wires which cross each other and a memory cell provided at each intersection of these first and second wires are laminated on top of each other, wherein the memory cells have a variable resistance element and a non-ohmic element laminated in the direction in which the memory cell layers are laminated and tapered in such a manner that the area in a cross section gradually becomes smaller from the bottom memory cell layer towards the top memory cell layer, and the variable resistance element and the non-ohmic element in the memory cells in a certain memory cell layer are laminated in the same order as the variable resistance element and the non-ohmic element of the memory cells in another memory cell layer.Type: GrantFiled: March 18, 2010Date of Patent: August 13, 2013Assignee: Kabushiki Kaisha ToshibaInventor: Hiroyuki Nagashima
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Patent number: 8477542Abstract: A semiconductor memory device comprises a plurality of memory layers arranged in multilayer, each memory layer including a cell array, the cell array containing a plurality of first parallel lines, a plurality of second parallel lines arranged crossing the first lines, and a plurality of memory cells connected at intersections of the first lines and the second lines; a pulse generator operative to generate pulses required for data access to the memory cell; and a control means operative to control the pulse generator such that the pulse output from the pulse generator has energy in accordance with the memory layer to which the access target memory cell belongs.Type: GrantFiled: October 12, 2011Date of Patent: July 2, 2013Assignee: Kabushiki Kaisha ToshibaInventors: Hiroyuki Nagashima, Naoya Tokiwa
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Patent number: 8446782Abstract: A semiconductor memory device comprises a plurality of memory layers arranged in multilayer, each memory layer including a cell array, the cell array containing a plurality of first parallel lines, a plurality of second parallel lines arranged crossing the first lines, and a plurality of memory cells connected at intersections of the first lines and the second lines; a pulse generator operative to generate pulses required for data access to the memory cell; and a control means operative to control the pulse generator such that the pulse output from the pulse generator has energy in accordance with the memory layer to which the access target memory cell belongs.Type: GrantFiled: October 12, 2011Date of Patent: May 21, 2013Assignee: Kabushiki Kaisha ToshibaInventors: Hiroyuki Nagashima, Naoya Tokiwa
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Patent number: 8441040Abstract: A semiconductor memory device according to an embodiment includes: a cell array block having, above a semiconductor substrate, a plurality of first and second wirings intersecting with one another, and a plurality of memory cells, the first and second wirings being separately formed in a plurality of layers in a perpendicular direction to the semiconductor substrate; and a first via wiring, connecting the first wiring in an n1-th layer of the cell array block with the first wiring in an n2-th layer, the semiconductor substrate or another metal wiring, and extending in a laminating direction of the cell array block. The first via wiring has a cross section orthogonal to the laminating direction of the cell array block. The cross section has an elliptical shape and a longer diameter in a direction perpendicular to the first wiring direction.Type: GrantFiled: September 20, 2010Date of Patent: May 14, 2013Assignee: Kabushiki Kaisha ToshibaInventors: Yoichi Minemura, Hiroyuki Nagashima