Patents by Inventor Hiroshi Iwata

Hiroshi Iwata 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: 20050002263
    Abstract: A writing control system providing high-speed writing to a nonvolatile semiconductor storage device, includes (a) a plurality of memory elements each having: a gate electrode provided on a semiconductor layer with an intervening gate insulating film; a channel region provided beneath the gate electrode; a diffusion region provided on both sides of the channel region, having an opposite polarity to the channel region; and a memory functioning member, provided on both sides of the gate electrode, having a function of holding electric charges, (b) a memory array including a page buffer circuit, and (c) CPU controlling writing to the memory array. The CPU loads a first plane of the page buffer circuit with a first byte of data and writes with the first byte of data stored in the first plane.
    Type: Application
    Filed: May 19, 2004
    Publication date: January 6, 2005
    Inventors: Yasuaki Iwase, Yoshifumi Yaoi, Hiroshi Iwata, Akihide Shibata, Yoshinao Morikawa, Masaru Nawaki
  • Publication number: 20050001262
    Abstract: A semiconductor storage device is provided with a gate electrode, a semiconductor layer, a gate insulating film sandwiched between the gate electrode and the semiconductor layer, a channel region under the gate electrode, diffusion regions provided respectively on two sides of the channel regions and being of the other conductivity region than the channel region, memory elements 1 provided respectively on two sides of the gate electrode and having a function of holding charges, and a word line driver circuit, in which the CMOS technique is used. The driver circuit includes a common node for supplying a potential for activating an output inverter for driving a row word line. While the semiconductor storage device is in a read mode, a CMOS inverter other than the output inverter controls a signal at the common node, the CMOS inverter connected to a read input line.
    Type: Application
    Filed: May 19, 2004
    Publication date: January 6, 2005
    Inventors: Yasuaki Iwase, Yoshifumi Yaoi, Hiroshi Iwata, Akihide Shibata, Yoshinao Morikawa, Masaru Nawaki
  • Publication number: 20050002240
    Abstract: The present invention provides a semiconductor memory device including: a memory cell array in which memory cells are arranged; a plurality of terminals for accepting commands issued by an external user; a command interface circuit for interfacing between the external user and the memory cell array; a write state machine for controlling the programming and erasing operations; and an output circuit for outputting an internal signal to the plurality of terminals, wherein the memory cell includes a gate electrode formed over a semiconductor layer via a gate insulating film, a channel region disposed below the gate electrode, diffusion regions disposed on both sides of the channel region and having a conductive type opposite to that of the channel region, and memory functional elements formed on both sides of the gate electrode and having the function of retaining charges.
    Type: Application
    Filed: May 18, 2004
    Publication date: January 6, 2005
    Applicant: Sharp Kabushiki Kaisha
    Inventors: Koji Hamaguchi, Masaru Nawaki, Yoshinao Morikawa, Hiroshi Iwata, Akihide Shibata
  • Publication number: 20050002236
    Abstract: A semiconductor storage device is provided, which comprises a memory array comprising memory elements. Each memory element comprises a gate electrode, a channel region, first and second diffusion regions, and first and second memory function sections provided an opposite aides of the gate electrode and having a function of retaining charges. The device further comprises a row decoder for selecting a word line in accordance with a row address, and a write control circuit for applying a write pulse to a bit line, which is connected to one of the first and second diffusion regions of the memory element connected to the selected word line, in accordance with a column address.
    Type: Application
    Filed: May 20, 2004
    Publication date: January 6, 2005
    Inventors: Yoshinao Morikawa, Masaru Nawaki, Hiroshi Iwata, Akihide Shibata
  • Publication number: 20040268027
    Abstract: A semiconductor memory device includes a page buffer circuit and an arrangement of memory elements each including: a gate electrode provided on a semiconductor layer with an intervening gate insulating film; a channel region provided beneath the gate electrode; a diffusion area provided on both sides of the channel region, having an opposite polarity to the channel region; and a memory functioning member provided on both sides of the gate electrodes, having a function of storing electric charge. The page buffer circuit provides a common resource shared between a memory array controller and a user. The page buffer circuit has two planes containing random access memory arrays. The page buffer circuit also includes a mode control section to facilitate access to the planes over a main bus in user mode and access to the planes by the memory array controller in memory control mode.
    Type: Application
    Filed: May 19, 2004
    Publication date: December 30, 2004
    Inventors: Yoshifumi Yaoi, Yasuaki Iwase, Hiroshi Iwata, Akihide Shibata, Yoshinao Morikawa, Masaru Nawaki
  • Publication number: 20040262665
    Abstract: A semiconductor storage device comprises memory function bodies that are formed on sidewalls of gate electrode located on one side and the other side of source/drain diffusion regions and have a function to retain electric charge or polarization. A quantity of electric charge flowing in a channel region changes depending on an amount of an electric charge or polarization retained in the memory function body specified by selecting a prescribed word line and a first bit line and a second bit line.
    Type: Application
    Filed: May 18, 2004
    Publication date: December 30, 2004
    Inventors: Hiroshi Iwata, Kouichirou Adachi, Akihide Shibata
  • Publication number: 20040264257
    Abstract: A semiconductor storage device is provided, which comprises a memory array comprising a plurality of memory elements, a section for performing an erase or program operation with respect to the memory array, a section for receiving a suspend command, and in response to the suspend command, suspending the erase or program operation, and a section for receiving a resume command, and in response to the resume command, resuming the suspended erase or program operation. Each of the plurality of memory elements comprises a gate electrode provided via a gate insulating film on a semiconductor layer, a channel region provided under the gate electrode, diffusion regions provided on opposite sides of the channel region and having a conductivity type opposite to that of the channel region, and memory function sections provided on opposite sides of the gate electrode and having a function of retaining charges.
    Type: Application
    Filed: May 20, 2004
    Publication date: December 30, 2004
    Inventors: Koji Hamaguchi, Masaru Nawaki, Yoshinao Morikawa, Hiroshi Iwata, Akihide Shibata
  • Publication number: 20040266109
    Abstract: A semiconductor storage element has a memory function body on opposite sides of a gate electrode formed on a semiconductor substrate. Each end of source/drain regions is located in the semiconductor substrate just under the memory function body and offset with respect to an edge of the gate electrode in a gate length direction to improve efficiency of electric charge injection into the memory function body. A storage state in the memory function body is found by detecting a amount of current between the source/drain regions, which current changes depending on the amount of the electric charge retained in the charge retention portion.
    Type: Application
    Filed: May 19, 2004
    Publication date: December 30, 2004
    Inventors: Takayuki Ogura, Hiroshi Iwata, Akihide Shibata
  • Publication number: 20040264270
    Abstract: A semiconductor storage device includes a field effect transistor which has a gate insulator, a gate electrode and a pair of source/drain diffusion regions on a semiconductor substrate. The device also includes a coating film made of a dielectric having a function of storing electric charge and formed on the substrate in such a manner as to cover an upper surface and side surfaces of the gate electrode. The device further includes an interlayer insulator formed on and in contact with the coating film. The device still further includes contact members which extend vertically through the interlayer insulator and the coating film on the source/drain diffusion regions and which are electrically connected to the source/drain diffusion regions, respectively. The coating film and the interlayer insulator are made of materials which are selectively etchable to each other. Thus, the issues of overerase and read failures due to the overerase can be solved, and the device reliability can be enhanced.
    Type: Application
    Filed: May 13, 2004
    Publication date: December 30, 2004
    Inventors: Hiroshi Iwata, Takayuki Ogura, Akihide Shibata, Kouichirou Adachi
  • Publication number: 20040264252
    Abstract: A semiconductor memory device includes a memory cell array in which plural memory cells are arranged, a memory operation circuit, connected to the memory cell array, for executing a memory operation on the memory cell array, and a command controller, connected to the memory operation circuit, for receiving a command from the outside and generating a predetermined control signal to the memory operation circuit on the basis of the received command to control execution of the memory operation by the memory operation circuit. The memory cell includes a gate electrode formed over a semiconductor layer via a gate insulating film, a channel region disposed below the gate electrode, diffusion regions disposed on both sides of the channel region and having a conductive type opposite to that of the channel region, and memory functional units formed on both sides of the gate electrode and having the function of retaining charges.
    Type: Application
    Filed: May 19, 2004
    Publication date: December 30, 2004
    Applicant: Sharp Kabushiki Kaisha
    Inventors: Yoshinao Morikawa, Masaru Nawaki, Hiroshi Iwata, Akihide Shibata
  • Publication number: 20040262650
    Abstract: A semiconductor device 1910 comprises a semiconductor substrate 100 including an isolation region 101 and an active region 102, a gate electrode 104 provided on the active region 102 via a gate insulating film 103, part of a side of the gate electrode 104 being covered with a gate electrode side wall insulating film 105, and a source region 106 and a drain region 106 provided on opposite sides of the gate electrode 104 via the gate electrode side wall insulating film 105. At least one of the source region 106 and the drain region 106 has a second surface for contacting a contact conductor. The second surface is tilted with respect to a first surface A-A′. An angle between the second surface and a surface of the isolation region is 80 degrees or less.
    Type: Application
    Filed: July 27, 2004
    Publication date: December 30, 2004
    Applicant: Sharp Kabushiki Kaisha
    Inventors: Hiroshi Iwata, Akihide Shibata, Seizo Kakimoto, Kouichiro Adachi, Masayuki Nakano
  • Publication number: 20040262666
    Abstract: A semiconductor storage device is provided, which comprises a memory array comprising memory elements, a write state machine for applying a first voltage for performing a write or erase operation, with respect to one of the memory elements, to the memory element via a bit line connected thereto, and thereafter, applying a second voltage for verifying whether or not the write or erase operation has been performed, to the memory element via the bit line, and a reset portion for grounding the bit line connected to the memory element after the write state machine has applied the first voltage and before the write state machine has applied the second voltage. Each memory element comprises a gate electrode, a channel region, diffusion regions, and memory function sections provided on opposite sides of the gate electrode and having a function of retaining charges.
    Type: Application
    Filed: May 20, 2004
    Publication date: December 30, 2004
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Nobuaki Matsuoka, Masaru Nawaki, Yoshinao Morikawa, Hiroshi Iwata, Akihide Shibata
  • Publication number: 20040257875
    Abstract: A semiconductor memory device includes a memory cell including a gate electrode formed on a semiconductor layer via a gate insulating film, a channel region disposed under the gate electrode, diffusion regions disposed on both sides of the channel region and having a conductive type opposite to that of the channel region, and memory functional units formed on both sides of the gate electrode and having a function of retaining charges; a switching transistor circuit including a negative voltage switching circuit for applying a negative voltage to the gate electrode of the memory cell, and a switching transistor connected to an output of the negative voltage switching circuit and a first voltage source for outputting a voltage having a voltage level lower than zero volt; a pull-up circuit connected to a control terminal of the switching transistor and selectively connected to a second voltage source for outputting a voltage having a voltage level higher than zero volt; and a pull-down circuit connected to the f
    Type: Application
    Filed: May 13, 2004
    Publication date: December 23, 2004
    Inventors: Yoshifumi Yaoi, Hiroshi Iwata, Akihide Shibata, Yoshinao Morikawa, Masaru Nawaki
  • Publication number: 20040256653
    Abstract: A semiconductor switching element and a semiconductor storage element each have a gate electrode, a pair of source/drain regions and a channel forming region. Memory function bodies having a function of storing electric charges are provided on opposite sides of the gate electrode of the semiconductor storage element. In the semiconductor storage element, an amount of current that flows from one of the source/drain regions to the other of the source/drain regions upon application of a voltage to the gate electrode is variable depending on an amount of electric charges retained in the memory function body.
    Type: Application
    Filed: May 11, 2004
    Publication date: December 23, 2004
    Inventors: Hiroshi Iwata, Takayuki Ogura, Akihide Shibata
  • Publication number: 20040257878
    Abstract: A semiconductor storage device to provided, which comprises a memory array comprising memory elements, a write state machine for performing a sequence of a program or erase operation with respect to the memory array, a decoder for decoding a signal indicating a current state of the write state machine, which is output from the write state machine, and outputting a status signal indicating a status of the program or erase operation with respect to the memory array, a status register for storing the status signal, and an output circuit for outputting the status signal stored in the status register. Each memory element comprises a gate electrode, a channel region, diffusion regions, and memory function sections provided on opposite sides of the gate electrode and having a function of retaining charges.
    Type: Application
    Filed: May 20, 2004
    Publication date: December 23, 2004
    Inventors: Yoshinao Morikawa, Masaru Nawaki, Hiroshi Iwata, Akihide Shibata
  • Publication number: 20040245564
    Abstract: A semiconductor storage device includes a field effect transistor having a gate insulator, a gate electrode and a pair of source/drain diffusion regions which are formed on a semiconductor substrate. Recesses are formed so as to increasingly widening sideways in cross section between opposite side portions of the gate electrode and the semiconductor substrate surface, respectively. Memory function bodies each of which is composed of a charge retention part made of a material having a function of storing electric charge, and an anti-dissipation dielectric having a function of preventing dissipation of stored electric charge, are formed on opposite sides of the gate electrode in such a fashion that the recesses are thereby buried. Thus, the semiconductor storage device is capable of solving the issues of overerase and read failures due to the overerase and enhancing the reliability.
    Type: Application
    Filed: May 18, 2004
    Publication date: December 9, 2004
    Inventors: Takayuki Ogura, Hiroshi Iwata, Akihide Shibata
  • Patent number: 6825528
    Abstract: A semiconductor device 1910 comprises a semiconductor substrate 100 including an isolation region 101 and an active region 102, a gate electrode 104 provided on the active region 102 via a gate insulating film 103, part of a side of the gate electrode 104 being covered with a gate electrode side wall insulating film 105, and a source region 106 and a drain region 106 provided on opposite sides of the gate electrode 104 via the gate electrode side wall insulating film 105. At least one of the source region 106 and the drain region 106 has a second surface for contacting a contact conductor. The second surface is tilted with respect to a first surface A-A′. An angle between the second surface and a surface of the isolation region is 80 degrees or less.
    Type: Grant
    Filed: August 12, 2002
    Date of Patent: November 30, 2004
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Hiroshi Iwata, Akihide Shibata, Seizo Kakimoto, Kouichiro Adachi, Masayuki Nakano
  • Publication number: 20040233724
    Abstract: A semiconductor memory device includes a field-effect transistor provided on a surface of a P-type transistor substrate. The field-effect transistor includes two N-type diffusion layer regions, a gate electrode, and a charge storage section. By applying a reference voltage to one of the N-type diffusion layer regions, a voltage higher than the reference voltage to the other of the N-type diffusion layer regions, a voltage lower than the reference voltage to the gate electrode, and a voltage higher than the reference voltage to the P-type semiconductor substrate, holes are injected into the charge storage section. Because the forward voltage is applied to a PN junction between one of the N-type diffusion layer regions and the P-type semiconductor substrate, it is possible to inject the holes into the charge storage section at the voltages lower than the voltages required if the forward voltage is not applied. Therefore, it is possible to decrease operating voltages of the semiconductor memory device.
    Type: Application
    Filed: May 10, 2004
    Publication date: November 25, 2004
    Inventors: Akihide Shibata, Hiroshi Iwata
  • Publication number: 20040233725
    Abstract: A method for programming a nonvolatile memory cell includes the steps of: applying a first pulse to a nonvolatile memory cell to accumulate a first amount of charge which is smaller than a target amount of charge; in the case where the accumulated first amount of charge is smaller than a second amount of charge, applying a second pulse train to the nonvolatile memory cell, so that charges in an amount close to the second amount of charge are accumulated in the nonvolatile memory cell; when the nonvolatile memory cell is determined as retaining charges larger than the second amount of charge, applying a third pulse train until charges within an allowable error range of the target amount of charge is stored in the memory cell.
    Type: Application
    Filed: May 18, 2004
    Publication date: November 25, 2004
    Inventors: Yasuaki Iwase, Yoshifumi Yaoi, Hiroshi Iwata, Akihide Shibata, Yoshinao Morikawa, Masaru Nawaki
  • Publication number: 20040233729
    Abstract: A semiconductor memory device includes a controller for programming a nonvolatile memory cell by applying a first pulse so that a first amount of charge which is smaller than a target amount of charge is accumulated in the nonvolatile memory cell, a second pulse train of pulses so that a second amount of charge which is smaller than the target amount of charge and larger than the first amount of charge is accumulated in the nonvolatile memory cell, a third pulse train of pulses so that a third amount of charge which falls within an allowable error range of the target amount of charge is accumulated in the nonvolatile memory cell.
    Type: Application
    Filed: May 18, 2004
    Publication date: November 25, 2004
    Inventors: Yasuaki Iwase, Yoshifumi Yaoi, Hiroshi Iwata, Akihide Shibata, Yoshinao Morikawa, Masaru Nawaki