Patents by Inventor Katsuro Sasaki

Katsuro Sasaki 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: 6473333
    Abstract: The present invention provides a circuit, in which a device typified by a PLED element is built into a flip-flop. In this case, a storage node of the device is low leakage. According to the present invention, it is possible to realize a SRAM that has nonvolatility while achieving high-speed operation. It is also possible to realize a flip-flop having the same characteristics. An example of a typical mode of the present invention is a storage circuit characterized by the following: a storage element is a device incorporating: a first path for a carrier; a first mode for storing a charge that generates an electric field where conductivity of the first path is changed; and a barrier structure through which a second carrier moves in response to given voltage so that the second carrier is stored in the first node; and the storage circuit includes a second node, to which information stored in the first node is outputted steadily in a state in which power is supplied.
    Type: Grant
    Filed: November 13, 2001
    Date of Patent: October 29, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Suguru Tachibana, Katsuro Sasaki, Kiyoo Itoh, Tomoyuki Ishii
  • Publication number: 20010037431
    Abstract: In a digital information system for realizing the sale of information or the like having a commercial value in the form of a digital signal, and an audio processor, and signal processor suitably used with the system, when a digital signal is received/delivered, a digital signal source is connected directly to a player for receiving and storing a specified information, which is reproduced by the player independently. A voice interval of a digital audio signal is processed to realize the slow and fast playback. The system includes a data compressor and a data extender of simple configuration. The value of the digital signal received/delivered can be exhibited directly. A selling system is constructed easily, and the player is simple in configuration and easy to operate by anyone.
    Type: Application
    Filed: June 22, 2001
    Publication date: November 1, 2001
    Inventors: Nobuo Hamamoto, Minoru Nagata, Masatoshi Ohtake, Katsutaka Kimura, Toshio Sasaki, Hiroshi Kishida, Isamu Orita, Katsuro Sasaki, Naoki Ozawa, Kazuhiro Kondo, Toshiaki Masuhara, Tadashi Onishi, Hidehito Obayashi, Kiyoshi Aiki, Hisashi Horikoshi
  • Patent number: 6282611
    Abstract: In a digital information system for realizing the sale of information or the like having a commercial value in the form of a digital signal, and an audio processor, and signal processor suitably used with the system, when a digital signal is received/delivered, a digital signal source is connected directly to a player for receiving and storing a specified information, which is reproduced by the player independently. A voice interval of a digital audio signal is processed to realize the slow and fast playback. The system includes a data compressor and a data extender of simple configuration. The value of the digital signal received/delivered can be exhibited directly. A selling system is constructed easily, and the player is simple in configuration and easy to operate by anyone.
    Type: Grant
    Filed: May 22, 1995
    Date of Patent: August 28, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Nobuo Hamamoto, Minoru Nagata, Masatoshi Ohtake, Katsutaka Kimura, Toshio Sasaki, Hiroshi Kishida, Isamu Orita, Katsuro Sasaki, Naoki Ozawa, Kazuhiro Kondo, Toshiaki Masuhara, Tadashi Onishi, Hidehito Obayashi, Kiyoshi Aiki, Hisashi Horikoshi
  • Patent number: 5834851
    Abstract: Herein disclosed is a semiconductor integrated circuit device comprising a SRAM having its memory cell composed of transfer MISFETs to be controlled through word lines and drive MISFETs. The gate electrodes of the drive MISFETs and the gate electrodes of the transfer MISFETs of the memory cell, and the word lines are individually formed of different conductive layers. The drive MISFETs and the transfer MISFETs are individually arranged to cross each other in the gate length direction. The word lines are extended in the gate length direction of the gate electrodes of the drive MISFETs and caused to cross the gate electrodes of the drive MISFETs partially.The two transfer MISFETs of the memory cell have their individual gate electrodes connected with two respective word lines spaced from each other and extended in an identical direction. The region defined by the two word lines is arranged therein with the two drive MISFETs and the source lines.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: November 10, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Shuji Ikeda, Satoshi Meguro, Soichiro Hashiba, Isamu Kuramoto, Atsuyoshi Koike, Katsuro Sasaki, Koichiro Ishibashi, Toshiaki Yamanaka, Naotaka Hashimoto, Nobuyuki Moriwaki, Shigeru Takahashi, Atsushi Hiraishi, Yutaka Kobayashi, Seigou Yukutake
  • Patent number: 5767554
    Abstract: Herein disclosed is a semiconductor integrated circuit device comprising a SRAM having its memory cell composed of transfer MISFETs to be controlled through word lines and drive MISFETs. The gate electrodes of the drive MISFETs and the gate electrodes of the transfer MISFETs of the memory cell, and the word lines are individually formed of different conductive layers. The drive MISFETs and the transfer MISFETs are individually arranged to cross each other in the gate length direction. The word lines are extended in the gate length direction of the gate electrodes of the drive MISFETs and caused to cross the gate electrodes of the drive MISFETs partially.The two transfer MISFETs of the memory cell have their individual gate electrodes connected with two respective word lines spaced from each other and extended in an identical direction. The region defined by the two word lines is arranged therein with the two drive MISFETs and the source lines.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: June 16, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Shuji Ikeda, Satoshi Meguro, Soichiro Hashiba, Isamu Kuramoto, Atsuyoshi Koike, Katsuro Sasaki, Koichiro Ishibashi, Toshiaki Yamanaka, Naotaka Hashimoto, Nobuyuki Moriwaki, Shigeru Takahashi, Atsushi Hiraishi, Yutaka Kobayashi, Seigou Yukutake
  • Patent number: 5731219
    Abstract: Herein disclosed is a semiconductor integrated circuit device comprising an SRAM having its memory cell composed of transfer MISFETs to be controlled through word lines and drive MISFETs, and a method of forming this device. The gate electrodes of the drive MISFETs and of the transfer MISFETs of the memory cell, and the word lines, are individually formed of different conductive layers. The two transfer MISFETs of the memory cell have their individual gate electrodes connected with two respective word lines spaced from each other and extended in an identical direction. The source line is formed of a conductive layer identical to that of the word line. An oxidation resisting film is formed on the gate electrodes of the drive MISFETs so as to reduce stress caused by oxidization of edge portions of these gate electrodes, and to reduce a resulting leakage current.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: March 24, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Shuji Ikeda, Satoshi Meguro, Soichiro Hashiba, Isamu Kuramoto, Atsuyoshi Koike, Katsuro Sasaki, Koichiro Ishibashi, Toshiaki Yamanaka, Naotaka Hashimoto, Nobuyuki Moriwaki, Shigeru Takahashi, Atsushi Hiraishi, Yutaka Kobayashi, Seigou Yukutake
  • Patent number: 5700704
    Abstract: A method is provided for manufacturing a semiconductor integrated circuit device which includes a capacitor element having a first electrode, a second electrode, and a dielectric film formed between said first electrode and said second electrode. In particular, the method includes the step of forming at least one of the first electrode and second electrode with a polycrystalline silicon film which is deposited over a semiconductor substrate by a CVD method and which is doped with an impurity during said deposition to decrease the resistance of the polycrystalline silicon film. The capacitor element formed by this method is particularly useful for memory cells of static random access memory devices.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: December 23, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Shuji Ikeda, Satoshi Meguro, Soichiro Hashiba, Isamu Kuramoto, Atsuyoshi Koike, Katsuro Sasaki, Koichiro Ishibashi, Toshiaki Yamanaka, Naotaka Hashimoto, Nobuyuki Moriwaki, Shigeru Takahashi, Atsushi Hiraishi, Yutaka Kobayashi, Seigou Yukutake
  • Patent number: 5687382
    Abstract: A memory system including a first memory area (MEM-A) implemented using memory units including low threshold voltage transistors powered by a low supply voltage source, and a second memory area (MEM-B) implemented using memory units including higher threshold voltage cells powered by a higher supply voltage source. The first memory area, MEM-A, is designated to contain frequently accessed variables, with less frequently accessed variables designated for storage in the second memory area, MEM-B. The most frequently accessed variables stored in MEM-A provide for fast access at a low power per access power dissipation level due to the lower supply voltage and lower threshold voltage design. Alternatively, the less frequently accessed variables stored in MEM-B require a high power per access, but negligible leakage current during static steady state conditions.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: November 11, 1997
    Assignee: Hitachi America, Ltd.
    Inventors: Hirotsugu Kojima, Katsuro Sasaki
  • Patent number: 5677887
    Abstract: A semiconductor static memory device, which has an increased storage capacity without imposing an increased access time, includes first, second and third metallic layers. To begin, word lines for the transfer MOSFETS are formed of the same polysilicon layer used to form the gate electrodes of the transfer MOSFETs of the memory device. A metallic layer of the first layer is used for local word lines, with the polysilicon word lines and local word lines being connected at their ends or inside of cell arrays. A metallic layer of the second layer is used for bit layers, and a metallic layer of the third layer is used for main word lines. Consequently, the word lines have a decreased time constant, allowing fast memory access. Each of sense amplifiers used in the memory device are formed with MOSFETs, which are disposed divisionally in adjacent locations. Preferably the gate electrodes of the divided MOSFETs are located symmetrically.
    Type: Grant
    Filed: March 10, 1995
    Date of Patent: October 14, 1997
    Assignees: Hitachi, Ltd., Hitachi ULSI Engineering Corporation
    Inventors: Koichiro Ishibashi, Katsuro Sasaki, Kunihiro Komiyaji, Toshiro Aoto, Sadayuki Morita
  • Patent number: 5656836
    Abstract: Herein disclosed is a semiconductor integrated circuit device comprising a SRAM having its memory cell composed of transfer MISFETs to be controlled through word lines and drive MISFETs. The gate electrodes of the drive MISFETs and the gate electrodes of the transfer MISFETs of the memory cell, and the word lines are individually formed of different conductive layers. The drive MISFETs and the transfer MISFETs are individually arranged to cross each other in the gate length direction. The word lines are extended in the gate length direction of the gate electrodes of the drive MISFETs and caused to cross the gate electrodes of the drive MISFETs partially.The two transfer MISFETs of the memory cell have their individual gate electrodes connected-with two respective word lines spaced from each other and extended in an identical direction. The region defined by the two word lines is arranged therein with the two drive MISFETs and the source lines.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: August 12, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Shuji Ikeda, Satoshi Meguro, Soichiro Hashiba, Isamu Kuramoto, Atsuyoshi Koike, Katsuro Sasaki, Koichiro Ishibashi, Toshiaki Yamanaka, Naotaka Hashimoto, Nobuyuki Moriwaki, Shigeru Takahashi, Atsushi Hiraishi, Yutaka Kobayashi, Seigou Yukutake
  • Patent number: 5652457
    Abstract: Herein disclosed is a semiconductor integrated circuit device comprising a SRAM having its memory cell composed of transfer MISFETs to be controlled through word lines and drive MISFETs. The gate electrodes of the drive MISFETs and the gate electrodes of the transfer MISFETs of the memory cell, and the word lines are individually formed of different conductive layers. The drive MISFETs and the transfer MISFETs are individually arranged to cross each other in the gate length direction. The word lines are extended in the gate length direction of the gate electrodes of the drive MISFETs and caused to cross the gate electrodes of the drive MISFETs partially.The two transfer MISFETs of the memory cell have their individual gate electrodes connected with two respective word lines spaced from each other and extended in an identical direction. The region defined by the two word lines is arranged therein with the two drive MISFETs and the source lines.
    Type: Grant
    Filed: November 30, 1994
    Date of Patent: July 29, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Shuji Ikeda, Satoshi Meguro, Soichiro Hashiba, Isamu Kuramoto, Atsuyoshi Koike, Katsuro Sasaki, Koichiro Ishibashi, Toshiaki Yamanaka, Naotaka Hashimoto, Nobuyuki Moriwaki, Shigeru Takahashi, Atsushi Hiraishi, Yutaka Kobayashi, Seigou Yukutake
  • Patent number: 5572480
    Abstract: Herein disclosed is a semiconductor integrated circuit device comprising a SRAM having its memory cell composed of transfer MISFETs to be controlled through word lines and drive MISFETs. The gate electrodes of the drive MISFETs and the gate electrodes of the transfer MISFETs of the memory cell, and the word lines are individually formed of different conductive layers. The drive MISFETs and the transfer MISFETs are individually arranged to cross each other in the gate length direction. The word lines are extended in the gate length direction of the gate electrodes of the drive MISFETs and caused to cross the gate electrodes of the drive MISFETs partially.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: November 5, 1996
    Assignee: Hitachi Ltd.
    Inventors: Shuji Ikeda, Satoshi Meguro, Soichiro Hashiba, Isamu Kuramoto, Atsuyoshi Koike, Katsuro Sasaki, Koichiro Ishibashi, Toshiaki Yamanaka, Naotaka Hashimoto, Nobuyuki Moriwaki, Shigeru Takahashi, Atsushi Hiraishi, Yutaka Kobayashi, Seigou Yukutake
  • Patent number: 5444000
    Abstract: A method of fabricating semiconductor integrated circuits with an improved yield rate is realized, which requires no special circuits for selecting normal circuit blocks. Removable temporary wires are connected to circuit blocks, which are thus tested. After removing the temporary wires, a plurality of normally-operating circuit blocks are interconnected by new main wires. The need of a special selecting circuit for replacing defective circuit blocks with normal circuit blocks is eliminated without increasing the delay time due to redundancy. The freedom of the main wiring formed after removal of the temporary wires is so high that the functional freedom of the system constructed is improved.
    Type: Grant
    Filed: March 3, 1994
    Date of Patent: August 22, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Norio Ohkubo, Makoto Suzuki, Katsuro Sasaki, Yoshio Homma
  • Patent number: 5424972
    Abstract: A carry look ahead circuit includes a first circuit for generating a logical sum of inputs, a second circuit for generating a logical product of the inputs, and a selection circuit for selecting either one of an output of the first circuit and an output of the second circuit in accordance with a carry signal from a lower figure to produce the selected output as a carry signal. Consequently, the number of circuit elements can be reduced greatly to configure the high speed and low power consumption carry look ahead circuit.
    Type: Grant
    Filed: September 3, 1993
    Date of Patent: June 13, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Norio Ohkubo, Makoto Suzuki, Katsuro Sasaki
  • Patent number: 5422839
    Abstract: A semiconductor static memory device, which has an increased storage capacity without imposing an increased access time, includes first, second and third metallic layers. To begin, word lines for the transfer MOSFETS are formed of the same polysilicon layer used to form the gate electrodes of the transfer MOSFETs of the memory device. A metallic layer of the first layer is used for local word lines, with the polysilicon word lines and local word lines being connected at their ends or inside of cell arrays. A metallic layer of the second layer is used for bit layers, and a metallic layer of the third layer is used for main word lines. Consequently, the word lines have a decreased time constant, allowing fast memory access. Each of sense amplifiers used in the memory device are formed with MOSFETs, which are disposed divisionally in adjacent locations. Preferably the gate electrodes of the divided MOSFETs are located symmetrically.
    Type: Grant
    Filed: September 10, 1993
    Date of Patent: June 6, 1995
    Assignees: Hitachi, Ltd., Hitachi ULSI Engineering Corporation
    Inventors: Koichiro Ishibashi, Katsuro Sasaki, Kunihiro Komiyaji, Toshiro Aoto, Sadayuki Morita
  • Patent number: 5239196
    Abstract: A MOSFET Static Random Access Memory (SRAM) cell has a symmetrical construction, with a pair of word lines. The word lines are in second level polysilicon, so that they may overlap the driving transistor gates which are in first level polysilicon.
    Type: Grant
    Filed: February 11, 1991
    Date of Patent: August 24, 1993
    Inventors: Shuji Ikeda, Satoshi Meguro, Soichiro Hashiba, Isamu Kuramoto, Atsuyoshi Koike, Katsuro Sasaki, Koichiro Ishibashi, Toshiaki Yamanaka, Naotaka Hashimoto, Nobuyuki Moriwaki
  • Patent number: 5146427
    Abstract: In a semiconductor memory, a latch circuit is arranged between the outputs of a sense amplifier and the inputs of a data output buffer. First pass-gates are arranged between the outputs of the sense amplifier and the latch circuit, while second pass-gates are arranged between the latch circuit and the inputs of the data output buffer. The outputs of the sense amplifier are transmitted to the inputs of the data output buffer through signal paths which bypass the first pass-gates, the latch circuit and the second pass-gates, whereby the data output buffer generates a data output quickly. Thereafter, the first pass-gates and the second pass-gates are controllably brought to a signal-through condition, whereby the output information items of the sense amplifier are stored in the latch circuit. The data output buffer holds the data output in conformity with the stored information items of the latch circuit.
    Type: Grant
    Filed: January 21, 1992
    Date of Patent: September 8, 1992
    Assignees: Hitachi Ltd., Hitachi VISI Engineering Corp.
    Inventors: Katsuro Sasaki, Nobuyuki Moriwaki, Shigeru Honjo, Hideaki Nakamura
  • Patent number: 5134581
    Abstract: In order to obtain a highly stable SRAM cell having a small cell area, a cell ratio R is set to be R=(W.sub.DEFF /L.sub.DEFF)/(W.sub.TEFF /L.sub.TEFF)<3 where L.sub.DEFF and W.sub.DEFF denote an effective channel length and an effective channel width of two driver MOSFETs 3 and 4 respectively, and L.sub.TEFF and W.sub.TEFF denote an effective channel length and an effective channel width of two transfer MOSFETs 5 and 6 respectively. Further, a maximum current I.sub.R flowing into the active loads MOSFETs 1 and 2 is set to be greater than a current I.sub.L (1.times.10.sup.-8 A) that flows into the driver MOSFET 5 when a threshold voltage is applied across the gate and the cource of the MOSFET 5. The pair of active load MOSFETs 1 and 2 are stacked on the driver MOSFETs 3 and 4 and on the transfer MOSFETs 5 and 6.
    Type: Grant
    Filed: October 29, 1990
    Date of Patent: July 28, 1992
    Assignees: Hitachi, Ltd., Hitachi VLSI Engineering Corp.
    Inventors: Koichiro Ishibashi, Katsuro Sasaki, Katsuhiro Shimohigashi, Toshiaki Yamanaka, Naotaka Hashimoto, Takashi Hashimoto, Akihiro Shimizu
  • Patent number: 5132771
    Abstract: A semiconductor static random access memory having a high .alpha.-ray immunity and a high packing density is provided which is also capable of high-speed operation. A semiconductor memory device comprises static random access memory cells each including a flip-flop circuit. Storage nodes of each flip-flop circuit have respective pn-junctions formed at regions sandwiched between gate electrodes of first insulated gate field effect transistors and gate electrodes of second insulated gate field effect transistors, respectively. The pn-junction has an area smaller than that of a channel portion of the first or second insulated gate field effect transistor.
    Type: Grant
    Filed: April 4, 1990
    Date of Patent: July 21, 1992
    Assignees: Hitachi, Ltd., Hitachi VLSI Engineering Corporation
    Inventors: Toshiaki Yamanaka, Naotaka Hashimoto, Takashi Hashimoto, Akihiro Shimizu, Koichiro Ishibashi, Katsuro Sasaki, Katsuhiro Shimohigashi, Eiji Takeda, Yoshio Sakai, Takashi Nishida, Osamu Minato, Toshiaki Masuhara, Shoji Hanamura, Shigeru Honjo, Nobuyuki Moriwaki
  • Patent number: 5126974
    Abstract: A MOS transistor sense amplifier employs cross coupled positive feedback for the load circuit of a differential amplifier with an equalizing switch at the amplifier output, and preferably also at the input. This basis amplifier circuit may be repeated in stages. When stages are employed, it is desirable that the first stage employs current mirror loading of the differential amplifier to reduce the data delay. Data delay is further reduced by providing strong amplification during the sense portion of the read cycle with a preamplifier, which preamplifier has its amplification reduced, preferably to unity by being turned off, when the sense portion of the cycle is finished, and most preferably when the input and output data lines are directly connected independently of the preamplifier, so that the preamplifier may be completely turned off to lower power consumption.
    Type: Grant
    Filed: January 16, 1990
    Date of Patent: June 30, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Katsuro Sasaki, Katsuhiro Shimohigashi, Koichiro Ishibashi, Shoji Hanamura