Patents by Inventor Hitoshi Iwai
Hitoshi Iwai 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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Publication number: 20150029791Abstract: A control circuit is configured to execute an erasing operation on a selected cell unit in a selected memory block. In the erasing operation, the control circuit raises the voltage of the bodies of the first memory transistors included in the selected cell unit to a first voltage, sets the voltage of the bodies of the first memory transistors included in the non-selected cell unit to a second voltage lower than the first voltage, and applies a third voltage equal to or lower than the second voltage to the gates of the first memory transistors included in the selected cell unit and the non-selected cell unit.Type: ApplicationFiled: October 13, 2014Publication date: January 29, 2015Applicant: KABUSHIKI KAISHA TOSHIBAInventors: Kiyotaro ITAGAKI, Masaru KITO, Ryu OGIWARA, Hitoshi IWAI
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Publication number: 20140369127Abstract: According to one embodiment, a semiconductor memory device includes a first string; a second string; and a controller. The first string is coupled with a first bit line and includes first memory cells. The second string is coupled with a second bit line and includes second memory cells. The controller executes writing first data into the first memory cells and writing second data into the second memory cells simultaneously. The controller reads data from the first and second strings after writing the first and second data.Type: ApplicationFiled: September 17, 2013Publication date: December 18, 2014Applicant: Kabushiki Kaisha ToshibaInventors: Tokumasa HARA, Naoya Tokiwa, Hiroshi Sukegawa, Hitoshi Iwai, Toshifumi Shano, Shirou Fujita
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Patent number: 8902657Abstract: According to one embodiment, a semiconductor memory device includes a plurality of blocks. The blocks includes a first selection transistor, a second selection transistor, a plurality of memory cell transistors, a first selection gate line and a second selection gate line, and word lines. One of the blocks holds information on a word line, a first selection gate line and/or a second selection gate line including a short-circuiting defect.Type: GrantFiled: March 15, 2013Date of Patent: December 2, 2014Assignee: Kabushiki Kaisha ToshibaInventors: Hitoshi Iwai, Shirou Fujita, Hiroshi Sukegawa, Toshio Fujisawa, Tokumasa Hara
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Patent number: 8873296Abstract: A control circuit is configured to execute an erasing operation on a selected cell unit in a selected memory block. In the erasing operation, the control circuit raises the voltage of the bodies of the first memory transistors included in the selected cell unit to a first voltage, sets the voltage of the bodies of the first memory transistors included in the non-selected cell unit to a second voltage lower than the first voltage, and applies a third voltage equal to or lower than the second voltage to the gates of the first memory transistors included in the selected cell unit and the non-selected cell unit.Type: GrantFiled: July 29, 2013Date of Patent: October 28, 2014Assignee: Kabushiki Kaisha ToshibaInventors: Kiyotaro Itagaki, Masaru Kito, Ryu Ogiwara, Hitoshi Iwai
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Publication number: 20140313829Abstract: A nonvolatile semiconductor memory device comprises a plurality of memory blocks, each including a plurality of cell units and each configured as a unit of execution of an erase operation. Each of the cell units comprises a memory string, a first transistor, a second transistor, and a diode. The first transistor has one end connected to one end of the memory string. The second transistor is provided between the other end of the memory string and a second line. The diode is provided between the other end of the first transistor and a first line. The diode comprises a second semiconductor layer of a first conductivity type and a third semiconductor layer of a second conductivity type.Type: ApplicationFiled: July 1, 2014Publication date: October 23, 2014Applicant: Kabushiki Kaisha ToshibaInventors: Hitoshi IWAI, Tomoki HIGASHI, Shinichi OOSERA
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Publication number: 20140284674Abstract: According to one embodiment, a semiconductor storage device includes a first capacitor, a second capacitor, a first selector gate, and a second selector gate. The first capacitor has first and second ends, the first end is electrically connected to an input end of a clock signal. The second capacitor as a spare has third and fourth ends and is electrically connected to the input end. The first selector gate is electrically connected between the second end of the first capacitor and a first node of the voltage generating circuit. The second selector gate is connected between the fourth end of the second capacitor and the first node of the voltage generating circuit. The first and second selector gates are switched based on an output voltage of the voltage generating circuit.Type: ApplicationFiled: September 6, 2013Publication date: September 25, 2014Inventor: Hitoshi IWAI
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Patent number: 8830765Abstract: A control circuit is configured to, during an erase operation, set a voltage of a first line connected to a selected cell unit to a voltage larger than a voltage of a gate of a first transistor included in the selected cell unit by an amount of a first voltage; set a voltage difference between a voltage of a first line connected to an unselected cell unit and a voltage of a gate of a first transistor included in the unselected cell unit to a second voltage, the first and second voltages being different; apply in the selected and unselected cell units a third voltage to a gate of at least one of dummy transistors in a dummy memory string; and apply a fourth voltage to a gate of another one of the dummy transistors in the dummy memory string, the fourth voltage being lower than the third voltage.Type: GrantFiled: April 25, 2013Date of Patent: September 9, 2014Assignee: Kabushiki Kaisha ToshibaInventor: Hitoshi Iwai
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Patent number: 8830289Abstract: At the time of forming an image, a rise in a temperature of a drive motor generates distortion in a bottom of a optical box of an optical scanning apparatus. If an opening is formed on the optical box to release heat, the optical box becomes easily distorted. To solve such a problem, according to the present invention, the optical scanning apparatus includes a rib which crosses over the opening formed at the bottom of the optical box.Type: GrantFiled: April 2, 2012Date of Patent: September 9, 2014Assignee: Canon Kabushiki KaishaInventor: Hitoshi Iwai
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Publication number: 20140233323Abstract: A control circuit is configured to, during an erase operation, set a voltage of a first line connected to a selected cell unit to a voltage larger than a voltage of a gate of a first transistor included in the selected cell unit by an amount of a first voltage. The control circuit is configured to, during the erase operation, set a voltage difference between a voltage of a first line connected to an unselected cell unit and a voltage of a gate of a first transistor included in the unselected cell unit to a second voltage, the second voltage differing from the first voltage. In addition, the control circuit is configured to, during the erase operation, apply in the selected cell unit and the unselected cell unit a third voltage to a gate of at least one of dummy memory transistors in a dummy memory string, and apply a fourth voltage to a gate of another one of the dummy memory transistors in the dummy memory string, the fourth voltage being lower than the third voltage.Type: ApplicationFiled: April 28, 2014Publication date: August 21, 2014Applicant: KABUSHIKI KAISHA TOSHIBAInventor: Hitoshi IWAI
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Patent number: 8804427Abstract: A nonvolatile semiconductor memory device comprises a plurality of memory blocks, each including a plurality of cell units and each configured as a unit of execution of an erase operation. Each of the cell units comprises a memory string, a first transistor, a second transistor, and a diode. The first transistor has one end connected to one end of the memory string. The second transistor is provided between the other end of the memory string and a second line. The diode is provided between the other end of the first transistor and a first line. The diode comprises a second semiconductor layer of a first conductivity type and a third semiconductor layer of a second conductivity type.Type: GrantFiled: December 2, 2013Date of Patent: August 12, 2014Assignee: Kabushiki Kaisha ToshibaInventors: Hitoshi Iwai, Tomoki Higashi, Shinichi Oosera
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Patent number: 8760924Abstract: 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: GrantFiled: March 22, 2012Date of Patent: June 24, 2014Assignee: Kabushiki Kaisha ToshibaInventors: Hitoshi Iwai, Tomoko Fujiwara, Hideaki Aochi, Masaru Kito
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Patent number: 8724383Abstract: A control circuit controls erase operation to erase data of memory transistors, correction write operation, and correction write verify operation. In the correction write operation, a erase threshold level of a memory transistor is moved to a positive threshold level after the erase operation. In the correction write verify operation, whether or not a threshold level of the result of the correction write operation reaches a first value is determined. In the correction write operation, the control circuit executes the correction write operation with respect to plural memory units connected to a common one of the bit lines as a group. The control circuit sequentially executes the correction write verify operation with respect to plural memory units in which the correction write operation is executed.Type: GrantFiled: January 26, 2012Date of Patent: May 13, 2014Assignee: Kabushiki Kaisha ToshibaInventor: Hitoshi Iwai
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Publication number: 20140085991Abstract: A nonvolatile semiconductor memory device comprises a plurality of memory blocks, each including a plurality of cell units and each configured as a unit of execution of an erase operation. Each of the cell units comprises a memory string, a first transistor, a second transistor, and a diode. The first transistor has one end connected to one end of the memory string. The second transistor is provided between the other end of the memory string and a second line. The diode is provided between the other end of the first transistor and a first line. The diode comprises a second semiconductor layer of a first conductivity type and a third semiconductor layer of a second conductivity type.Type: ApplicationFiled: December 2, 2013Publication date: March 27, 2014Applicant: Kabushiki Kaisha ToshibaInventors: Hitoshi IWAI, Tomoki HIGASHI, Shinichi OOSERA
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Publication number: 20140071756Abstract: According to one embodiment, a semiconductor memory device includes a plurality of blocks. The blocks includes a first selection transistor, a second selection transistor, a plurality of memory cell transistors, a first selection gate line and a second selection gate line, and word lines. One of the blocks holds information on a word line, a first selection gate line and/or a second selection gate line including a short-circuiting defect.Type: ApplicationFiled: March 15, 2013Publication date: March 13, 2014Applicant: KABUSHIKI KAISHA TOSHIBAInventors: Hitoshi Iwai, Shirou Fujita, Hiroshi Sukegawa, Toshio Fujisawa, Tokumasa Hara
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Patent number: 8659947Abstract: A nonvolatile semiconductor memory device comprises a plurality of memory blocks, each including a plurality of cell units and each configured as a unit of execution of an erase operation. Each of the cell units comprises a memory string, a first transistor, a second transistor, and a diode. The first transistor has one end connected to one end of the memory string. The second transistor is provided between the other end of the memory string and a second line. The diode is provided between the other end of the first transistor and a first line. The diode comprises a second semiconductor layer of a first conductivity type and a third semiconductor layer of a second conductivity type.Type: GrantFiled: April 25, 2013Date of Patent: February 25, 2014Assignee: Kabushiki Kaisha ToshibaInventors: Hitoshi Iwai, Tomoki Higashi, Shinichi Oosera
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Publication number: 20130342628Abstract: An optical scanning apparatus includes a light source configured to emit a light beam, a rotating polygon mirror configured to deflect the light beam such that the light beam scans a photosensitive member, an optical box to which the rotating polygon mirror is attached and which includes a first portion, and a holding member configured to hold the light source, including a second portion and a protrusion portion, and attached to the optical box such that the first portion of the optical box and the second portion of the holding member form a gap therebetween, wherein the holding member is attached to the optical box with an adhesive poured into the gap, and the protrusion portion is arranged toward the optical box from the holding member along a position in the gap into which the adhesive is poured to prevent the adhesive from falling off the position.Type: ApplicationFiled: June 20, 2013Publication date: December 26, 2013Inventor: Hitoshi Iwai
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Publication number: 20130314994Abstract: A control circuit is configured to execute an erasing operation on a selected cell unit in a selected memory block. In the erasing operation, the control circuit raises the voltage of the bodies of the first memory transistors included in the selected cell unit to a first voltage, sets the voltage of the bodies of the first memory transistors included in the non-selected cell unit to a second voltage lower than the first voltage, and applies a third voltage equal to or lower than the second voltage to the gates of the first memory transistors included in the selected cell unit and the non-selected cell unit.Type: ApplicationFiled: July 29, 2013Publication date: November 28, 2013Applicant: KABUSHIKI KAISHA TOSHIBAInventors: Kiyotaro ITAGAKI, Masaru Kito, Ryu Ogiwara, Hitoshi Iwai
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Patent number: 8531901Abstract: A semiconductor memory device comprises a cell array, voltage generation circuits, and a control circuit. The cell array comprises memory cell strings. The voltage generation circuits are arranged below the cell array. Each of the memory cell strings comprises a semiconductor layer, control gates, and memory cell transistors. The semiconductor layer comprises a pair of pillar portions, and a connecting portion. The control gates intersect the pillar portion. The memory cell transistors are formed at intersections of the pillar portion and the control gates. In a write operation and a read operation, the control circuit does not drive voltage generation circuits which give noise to memory cell strings as a write target and a read target, and drives voltage generation circuits which do not give noise to the memory cell strings as the write target and the read target.Type: GrantFiled: August 2, 2011Date of Patent: September 10, 2013Assignee: Kabushiki Kaisha ToshibaInventors: Ryu Ogiwara, Hitoshi Iwai, Kiyotaro Itagaki
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Publication number: 20130229876Abstract: A nonvolatile semiconductor memory device comprises a plurality of memory blocks, each including a plurality of cell units and each configured as a unit of execution of an erase operation. Each of the cell units comprises a memory string, a first transistor, a second transistor, and a diode. The first transistor has one end connected to one end of the memory string. The second transistor is provided between the other end of the memory string and a second line. The diode is provided between the other end of the first transistor and a first line. The diode comprises a second semiconductor layer of a first conductivity type and a third semiconductor layer of a second conductivity type.Type: ApplicationFiled: April 25, 2013Publication date: September 5, 2013Applicant: Kabushiki Kaisha ToshibaInventors: Hitoshi IWAI, Tomoki Higashi, Shinichi Oosera
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Patent number: 8514627Abstract: A control circuit is configured to execute an erasing operation on a selected cell unit in a selected memory block. In the erasing operation, the control circuit raises the voltage of the bodies of the first memory transistors included in the selected cell unit to a first voltage, sets the voltage of the bodies of the first memory transistors included in the non-selected cell unit to a second voltage lower than the first voltage, and applies a third voltage equal to or lower than the second voltage to the gates of the first memory transistors included in the selected cell unit and the non-selected cell unit.Type: GrantFiled: September 18, 2011Date of Patent: August 20, 2013Assignee: Kabushiki Kaisha ToshibaInventors: Kiyotaro Itagaki, Masaru Kito, Ryu Ogiwara, Hitoshi Iwai