Patents by Inventor Shuji Ikeda

Shuji Ikeda 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: 5780328
    Abstract: When the source and drain regions (an n.sup.- type semiconductor region and an n.sup.+ type semiconductor region) of a complementary MISFET and a p-type semiconductor region for use as a punch-through stopper are formed in a p-type well in a substrate having a p- and an n-type well, p-type impurities for the punch-through stopper are suppressed from being supplied to the feeding portion (an n.sup.+ type semiconductor region) of the n-type well.
    Type: Grant
    Filed: April 7, 1997
    Date of Patent: July 14, 1998
    Assignees: Hitachi, Ltd., Hitachi ULSI Engineering Co., Ltd.
    Inventors: Kazushi Fukuda, Yasuko Yoshida, Yutaka Hoshino, Naotaka Hashimoto, Kyoichiro Asayama, Yuuki Koide, Keiichi Yoshizumi, Eri Okamoto, Satoru Haga, Shuji Ikeda
  • Patent number: 5780910
    Abstract: In a complete CMOS SRAM having a memory cell composed of six MISFETs formed over a substrate, a capacitor element having a stack structure is formed of a lower electrode covering the memory cell, an upper electrode, and a capacitor insulating film (dielectric film) interposed between the lower electrode and the upper electrode. One electrode (the lower electrode) of the capacitor element is connected to one storage node of a flip-flop circuit, and the other electrode (the upper electrode) is connected to the other storage node. As a result, the storage node capacitance of the memory cell of the SRAM is increased to improve the soft error resistance.
    Type: Grant
    Filed: July 17, 1996
    Date of Patent: July 14, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Naotaka Hashimoto, Yutaka Hoshino, Shuji Ikeda
  • 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: 5754467
    Abstract: A SRAM of complete CMOS type having its memory cell composed of six MISFETs, in which a pair of local wiring lines for connecting the input/output terminals of CMOS inverters are formed of a refractory metal silicide layer formed over a first conducting layer constituting the individual gate electrodes of the drive MISFETs, the transfer MISFETs and the load MISFETs of the memory cell and in which a reference voltage line formed over the local wiring lines is arranged to be superposed over the local wiring lines to form a capacitor. The capacitor is formed between the local wiring lines and the first conducting layer by superposing the local wiring lines over the first conducting layer. Moreover, the local wiring lines are formed by using a structure with decreased resistance such as silicided structure. In addition, there are made common the processing for lowering the resistance of the gate electrode of the transfer MISFETs and the processing for forming the local wiring lines.
    Type: Grant
    Filed: May 25, 1995
    Date of Patent: May 19, 1998
    Assignees: Hitachi, Ltd., Hitachi ULSI Engineering Corp.
    Inventors: Shuji Ikeda, Toshiaki Yamanaka, Kenichi Kikushima, Shinichiro Mitani, Kazushige Sato, Akira Fukami, Masaya Iida, Akihiro Shimizu
  • 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: 5670793
    Abstract: A semiconductor device containing a polycrystalline silicon thin film wherein crystal grains of the silicon thin film have mainly a columnar structure and a crystal orientation of individual crystal grains is almost in a uniform direction can be produced by depositing a non-impurity-doped silicon thin film or an impurity layer on an interface of underlying film, followed by deposition of impurity-doped silicon thin film, if necessary, followed by heat treatment for polycrystallization.
    Type: Grant
    Filed: September 14, 1995
    Date of Patent: September 23, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Hideo Miura, Shunji Moribe, Hisayuki Kato, Atsuyoshi Koike, Shuji Ikeda, Asao Nishimura
  • 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: 5610856
    Abstract: An increase in the GND resistance and a drop in the resistance against electromigration are minimized when the ground voltage lines for shunting are finely constituted by using an Al wiring of the same layer as the pad layer, owing to the employment of a layout in which the arrangement of connection holes 24, 26 in a pad layer connected to one (data line) of the complementary data lines and the arrangement of connection holes in a pad layer connected to the other one (data line bar) of the complementary data lines, are inverted from each other every two bits of memory cells in the SRAM along the direction in which the complementary data lines extend.
    Type: Grant
    Filed: March 4, 1996
    Date of Patent: March 11, 1997
    Assignees: Hitachi, Ltd., Hitachi ULSI Engineering Corp.
    Inventors: Keiichi Yoshizumi, Satoru Haga, Shuji Ikeda, Kiichi Makuta, Takeshi Fukazawa
  • 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: 5543652
    Abstract: Negative characteristic MISFETs, which are of the same channel conductivity type and which have different threshold voltages, are formed in a doped silicon thin film deposited over a substrate and are connected in channel-to-channel series with each other. The pair of series-connected negative characteristic MISFETs, a resistive element, an information storage capacitive element and a transfer MISFET constitute an SRAM memory cell. Equivalently, a negative characteristic MISFET having a current-voltage characteristic defined by a negative resistance curve can be used in lieu of the pair of series-connected negative characteristic MISFETs in the formation of the individual memory cells of the SRAM. The negative resistance curve of the negative characteristic MISFET is shaped such that the linear current-voltage characteristic curve corresponding to the resistive element of the memory cell intersects the negative resistance curve at at least three location points.
    Type: Grant
    Filed: July 29, 1993
    Date of Patent: August 6, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Shuji Ikeda, Makoto Saeki
  • Patent number: 5508540
    Abstract: A SRAM having its memory cell constructed to include transfer MISFETs to be controlled by word lines and a flip-flop circuit having driver MISFETs and load MISFETs. Plate electrodes of large area fixed on predetermined power source lines are arranged over the load MISFETs such that the plate electrodes over the offset region of the load MISFETs are formed with an opening. A silicon nitride film having a thickness permeable to hydrogen but not to humidity is formed over the transfer MISFETs and the driver MISFETs formed over the main surface of a semiconductor substrate and the load MISFETs formed of a polycrystalline silicon film deposited on the driver MISFETs.
    Type: Grant
    Filed: February 2, 1994
    Date of Patent: April 16, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Shuji Ikeda, Koichi Imato, Kazuo Yoshizaki, Kohji Yamasaki, Soichiro Hashiba, Keiichi Yoshizumi, Yasuko Yoshida, Kousuke Okuyama, Mitsugu Oshima, Kazushi Tomita, Tsuyoshi Tabata, Kazushi Fukuda, Junichi Takano, Toshiaki Yamanaka, Chiemi Hashimoto, Motoko Kawashima, Fumiyuki Kanai, Takashi Hashimoto
  • Patent number: 5444012
    Abstract: In depositing a silicon oxide film which constitutes part of a final passivation film onto a bonding pad formed on an interlayer insulating film, the silicon oxide depositing step is divided in two stages, and after the first deposition, the bonding pad is once exposed by etching, then the second deposition is performed, whereby the silicon oxide film which has thus been deposited in two stages is formed over a fuse element formed under the interlayer insulating film, while on the bonding pad is formed only the silicon oxide film deposited in the second stage. As a result, at the time of etching polyimide resin, silicon nitride film and silicon oxide film successively to expose the bonding pad, there remains a sufficient thickness of insulating film between the bottom of an aperture which is formed at the same time and the fuse element. Thereafter, an electrical test is conducted while applying a probe to the bonding pad and, where required, the fuse element located under the aperture is cut.
    Type: Grant
    Filed: July 20, 1994
    Date of Patent: August 22, 1995
    Assignees: Hitachi, Ltd., Hitachi ULSI Engineering Corp.
    Inventors: Keiichi Yoshizumi, Kazushi Fukuda, Seiichi Ariga, Shuji Ikeda, Makoto Saeki, Kiyoshi Nagai, Soichiro Hashiba, Shinji Nishihara, Fumiyuki Kanai
  • Patent number: 5396100
    Abstract: Herein disclosed is a semiconductor integrated circuit device which has a memory array or a memory mat formed of memory cells arranged regularly in a matrix shape. At the end portion or inside of the memory array or memory cell in the region of the device where the patterning of the memory cells is discontinued or interrupted, the shape of an element isolating insulating film, which is formed for regulating the memory cells having pattern interruptions, is made substantially identical to the shape of the element isolating insulating film for regulating the memory cells in the region of the device where the patternings of the memory cells are of an uninterrupted regular form. In the location on the chip front face where the regular patterns associated with the memory area are discontinued, there is formed a dummy pattern having a shape made substantially identical to that of a gate electrode arranged at the end portion of the location where the regular patterns are interrupted.
    Type: Grant
    Filed: March 31, 1992
    Date of Patent: March 7, 1995
    Assignees: Hitachi, Ltd., Hitachi VLSI Engineering Corp.
    Inventors: Kohji Yamasaki, Nobuyuki Moriwaki, Shuji Ikeda, Hideaki Nakamura, Shigeru Honjo
  • 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: 5122857
    Abstract: A static RAM having first word lines each defined by extended gate electrodes of MISFETs constituting memory cells, and second word lines which are separate from the first word lines. The RAM further has a wiring for supplying a fixed potential such as a ground potential to the memory cells, the wiring being formed from the same layer as that for forming the second word lines.
    Type: Grant
    Filed: January 8, 1991
    Date of Patent: June 16, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Shuji Ikeda, Katsuro Sasaki, Kouichi Nagasawa, Satoshi Meguro
  • Patent number: 5087956
    Abstract: An SRAM including a memory cell having a high-resistance load element. The load element is formed from a polysilicon film, and an impurity is introduced into at least a part of the polysilicon film for the purpose of increasing the threshold voltage of a parasitic MISFET formed using the load element as its channel region. Alternatively, the deposition of the polysilicon film is carried out at a relatively high temperature, thereby preventing any increase in the current flowing through the load element, and thus reducing the power dissipation in the SRAM.
    Type: Grant
    Filed: May 30, 1989
    Date of Patent: February 11, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Shuji Ikeda, Satoshi Meguro, Kotaro Nishimura, Sho Yamamoto, Nobuyoshi Tanimura
  • Patent number: 5079611
    Abstract: Herein disclosed is a semiconductor integrated circuit device having a SRAM, in which two MISFETs of a flip-flop circuit of a memory cell are connected directly with an n.sup.+ -type drain region so that they are cross coupled; and in which a p.sup.+ -type semiconductor region is formed below a direct contact part by making use of the mask used in the step of forming contact holes for the direct contact part. The p.sup.+ -type semiconductor region aids as a barrier to prevent soft errors of the SRAM due to .alpha.-particles.
    Type: Grant
    Filed: October 18, 1990
    Date of Patent: January 7, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Shuji Ikeda, Satoshi Meguro, Makoto Motoyoshi, Osamu Minato
  • Patent number: 5055420
    Abstract: After contact holes for the P- and N-type source or drain regions of P- and N-channel MOSFETs have been made at a common step, an N-type impurity is ion-implanted into at least the N-type source or drain regions through the contact holes. The N-type impurity is annealed to fornm an N-type region which is deeper than the N-type source or drain regions. During the annealing treatment, the N-type source or drain regions are covered with an insulating film.
    Type: Grant
    Filed: May 9, 1989
    Date of Patent: October 8, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Shuji Ikeda, Kouichi Nagasawa, Makoto Motoyoshi, Kiyoshi Nagai, Satoshi Meguro