Patents by Inventor Isamu Asano

Isamu Asano 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: 20030141533
    Abstract: Disclosed are a semiconductor integrated circuit device and a method of manufacturing the same capable of improving the characteristics of the semiconductor integrated circuit device by reducing a leakage current of a capacitor used in a DRAM memory cell. A data storage capacitor connected to a data transfer MISFET in a memory cell forming area via plugs is formed in the following manner. That is, a lower electrode composed of an Ru film is formed in a hole in a silicon oxide film, and then, a tantalum oxide film is deposited on the lower electrode. Thereafter, a first thermal treatment in an oxidizing atmosphere is performed to the film at a temperature sufficient to repair an oxygen defect and having no influence on the materials below the tantalum oxide film. Further, a second thermal treatment in an inactive atmosphere is performed at a temperature at which the tantalum oxide film is not completely crystallized (650° C.) and higher than that applied in the later process.
    Type: Application
    Filed: January 28, 2003
    Publication date: July 31, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Yoshitaka Nakamura, Isamu Asano, Shinpei Iijima, Masahiko Hiratani, Hiroshi Sakuma
  • Publication number: 20030143864
    Abstract: With a view to preventing the oxidation of a metal film at the time of light oxidation treatment after gate patterning and at the same time to making it possible to control the reproducibility of oxide film formation and homogeneity of oxide film thickness at gate side-wall end portions, in a gate processing step using a poly-metal, a gate electrode is formed by patterning a gate electrode material which has been deposited over a semiconductor wafer 1A having a gate oxide film formed thereon and has a poly-metal structure and then, the principal surface of the semiconductor wafer 1A heated to a predetermined temperature or vicinity thereof is supplied with a hydrogen gas which contains water at a low concentration, the water having been formed from hydrogen and oxygen by a catalytic action, to selectively oxidize the principal surface of the semiconductor wafer 1A, whereby the profile of the side-wall end portions of the gate electrode is improved.
    Type: Application
    Filed: January 31, 2003
    Publication date: July 31, 2003
    Inventors: Yoshikazu Tanabe, Isamu Asano, Makoto Yoshida, Naoki Yamamoto, Masayoshi Saito, Nobuyoshi Natsuaki
  • Publication number: 20030132479
    Abstract: In order to improve connection reliability of a feeding interconnection connected to an electrode of each of the information storage capacitive elements of a DRAM, the formation of a through hole for connecting the information storage capacitive element formed over each memory cell selection MISFET and a feeding interconnection is performed in a process different from that for the formation of a through hole for connecting an interconnection of a second wiring layer in a peripheral circuit, which is formed over the information storage capacitive element and an interconnection corresponding to a first wiring layer.
    Type: Application
    Filed: January 3, 2003
    Publication date: July 17, 2003
    Inventors: Yoshitaka Nakamura, Masayoshi Hirasawa, Isamu Asano, Tsuyoshi Tamaru, Satoru Yamada, Keizo Kawakita, Toshihiro Sekiguchi, Yoshitaka Tadaki, Takuya Fukuda
  • Patent number: 6548847
    Abstract: Herein disclosed is a semiconductor integrated circuit device fabricating process for forming MISFETs over the principal surface in those active regions of a substrate, which are surrounded by inactive regions formed of an element separating insulating film and channel stopper regions, comprising: the step of for forming a first mask by a non-oxidizable mask and an etching mask sequentially over the principal surface of the active regions of the substrate; the step of forming a second mask on and in self-alignment with the side walls of the first mask by a non-oxidizable mask thinner than the non-oxidizable mask of the first mask and an etching mask respectively; the step of etching the principal surface of the inactive regions of the substrate by using the first mask and the second mask; the step of forming the element separating insulating film over the principal surface of the inactive regions of the substrate by an oxidization using the first mask and the second mask; and the step of forming the channel s
    Type: Grant
    Filed: July 9, 2001
    Date of Patent: April 15, 2003
    Assignees: Hitachi, Ltd., Hitachi VLSI Engineering Corp.
    Inventors: Jun Sugiura, Osamu Tsuchiya, Makoto Ogasawara, Fumio Ootsuka, Kazuyoshi Torii, Isamu Asano, Nobuo Owada, Mitsuaki Horiuchi, Tsuyoshi Tamaru, Hideo Aoki, Nobuhiro Otsuka, Seiichirou Shirai, Masakazu Sagawa, Yoshihiro Ikeda, Masatoshi Tsuneoka, Toru Kaga, Tomotsugu Shimmyo, Hidetsugu Ogishi, Osamu Kasahara, Hiromichi Enami, Atsushi Wakahara, Hiroyuki Akimori, Sinichi Suzuki, Keisuke Funatsu, Yoshinao Kawasaki, Tunehiko Tubone, Takayoshi Kogano, Ken Tsugane
  • Publication number: 20030064578
    Abstract: [Object] To prevent Al wiring formed on a via-hole in which a CVD-TiN film is embedded from corroding.
    Type: Application
    Filed: November 5, 2002
    Publication date: April 3, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Yoshitaka Nakamura, Tsuyoshi Tamaru, Naoki Fukuda, Hidekazu Goto, Isamu Asano, Hideo Aoki, Keizo Kawakita, Satoru Yamada, Katsuhiko Tanaka, Hiroshi Sakuma, Masayoshi Hirasawa
  • Patent number: 6528888
    Abstract: An integrated circuit. The circuit includes a memory cell array including wordlines 201 formed on a substrate and bitlines 200 and capacitors 203 formed over the wordlines. The bitlines have a first thickness and pitch. The circuit also includes circuits peripheral to the array including transistors formed in the substrate and conductors 202 over the transistors. The conductors have a second thickness and pitch. The circuit is further characterized in that the bitlines and conductors are formed in a common conductive layer. In further embodiments, the first thickness and pitch are smaller than the second thickness and pitch.
    Type: Grant
    Filed: February 2, 2001
    Date of Patent: March 4, 2003
    Assignee: Texas Instruments Incorporated
    Inventors: Chih-Chen Cho, Jeffrey A. McKee, William R. McKee, Isamu Asano, Robert Y. Tsu
  • Patent number: 6528403
    Abstract: With a view to preventing the oxidation of a metal film at the time of light oxidation treatment after gate patterning and at the same time to making it possible to control the reproducibility of oxide film formation and homogeneity of oxide film thickness at gate side-wall end portions, in a gate processing step using a poly-metal, a gate electrode is formed by patterning a gate electrode material which has been deposited over a semiconductor wafer 1A having a gate oxide film formed thereon and has a poly-metal structure and then, the principal surface of the semiconductor wafer 1A heated to a predetermined temperature or vicinity thereof is supplied with a hydrogen gas which contains water at a low concentration, the water having been formed from hydrogen and oxygen by a catalytic action, to selectively oxidize the principal surface of the semiconductor wafer 1A, whereby the profile of the side-wall end portions of the gate electrode is improved.
    Type: Grant
    Filed: December 13, 2001
    Date of Patent: March 4, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Yoshikazu Tanabe, Isamu Asano, Makoto Yoshida, Naoki Yamamoto, Masayoshi Saito, Nobuyoshi Natsuaki
  • Patent number: 6521932
    Abstract: It is an object of the present invention to provide a high-reliability semiconductor device having a storage capacitor and wiring using copper for a main conductive film. Under the above object, the present invention provides a semiconductor device comprising: a semiconductor substrate; a storage capacitor formed on the main surface side of the semiconductor substrate and being a first electrode and a second electrode arranged so as to put a capacitor insulation film; a wiring conductor formed on the main surface side of the semiconductor substrate and including the copper (Cu) element; and a first film formed on the surface of the wiring conductor; wherein a material configuring the first film and a material configuring the first electrode and/or the second electrode include the same element.
    Type: Grant
    Filed: March 14, 2000
    Date of Patent: February 18, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Yukihiro Kumagai, Hideo Miura, Hiroyuki Ohta, Tomio Iwasaki, Isamu Asano
  • Publication number: 20030030088
    Abstract: It is an object of the present invention to provide a high-reliability semiconductor device having a storage capacitor and wiring using copper for a main conductive film. Under the above object, the present invention provides a semiconductor device comprising: a semiconductor substrate; a storage capacitor formed on the main surface side of the semiconductor substrate and being a first electrode and a second electrode arranged so as to put a capacitor insulation film; a wiring conductor formed on the main surface side of the semiconductor substrate and including the copper (Cu) element; and a first film formed on the surface of the wiring conductor; wherein a material configuring the first film and a material configuring the first electrode and/or the second electrode include the same element.
    Type: Application
    Filed: September 27, 2002
    Publication date: February 13, 2003
    Inventors: Yukihiro Kumagai, Hideo Miura, Hiroyuki Ohta, Tomio Iwasaki, Isamu Asano
  • Publication number: 20030006441
    Abstract: In a peripheral circuit region of a DRAM, two connection holes 17a, 17b for connecting a first layer line 14 and a second layer line 26 electrically are opened separately in two processes. After forming the connection holes 17a and 17b, plugs 18a and 215a are formed in the connection holes 17a and 17b, respectively.
    Type: Application
    Filed: December 10, 1998
    Publication date: January 9, 2003
    Inventors: YOSHITAKA NAKAMURA, ISAMU ASANO, KEIZOU KAWAKITA, SATORU YAMADA
  • Patent number: 6503819
    Abstract: With a view to preventing the oxidation of a metal film at the time of light oxidation treatment after gate patterning and at the same time to making it possible to control the reproducibility of oxide film formation and homogeneity of oxide film thickness at gate side-wall end portions, in a gate processing step using a poly-metal, a gate electrode is formed by patterning a gate electrode material which has been deposited over a semiconductor wafer 1A having a gate oxide film formed thereon and has a poly-metal structure and then, the principal surface of the semiconductor wafer 1A heated to a predetermined temperature or vicinity thereof is supplied with a hydrogen gas which contains water at a low concentration, the water having been formed from hydrogen and oxygen by a catalytic action, to selectively oxidize the principal surface of the semiconductor wafer 1A, whereby the profile of the side-wall end portions of the gate electrode is improved.
    Type: Grant
    Filed: January 31, 2001
    Date of Patent: January 7, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Yoshikazu Tanabe, Isamu Asano, Makoto Yoshida, Naoki Yamamoto, Masayoshi Saito, Nobuyoshi Natsuaki
  • Publication number: 20030001214
    Abstract: An active region (L) with a metal insulator semiconductor field effect transistor (MISFET) (Qs) formed therein for selection of a DRAM memory cell, which makes up a memory cell of the DRAM, is arranged to have an island-like pattern that linearly extends in an X direction on one principal surface of a semiconductor substrate (1). The memory-cell selection MISFET (Qs) has an insulated gate electrode (7) (word line WL) that extends along a Y direction on the principal surface of the semiconductor substrate (1) with the same width kept along the length thereof, which gate electrode is arranged to oppose another gate electrode (7) (word line WL) adjacent thereto at a prespecified distance or pitch that is narrower than said width.
    Type: Application
    Filed: August 27, 2002
    Publication date: January 2, 2003
    Inventors: Makoto Yoshida, Takahiro Kumauchi, Yoshitaka Tadaki, Isamu Asano, Norio Hasegawa, Keizo Kawakita
  • Patent number: 6492730
    Abstract: The semiconductor device is formed according to the following steps. A TiN film 71 and a W film 72 are deposited on a silicon oxide film 64 including the inside of a via-hole 66 by the CVD method and thereafter, the W film 72 and TiN film 71 on the silicon oxide film 64 are etched back to leave only the inside of the via-hole 66 and form a plug 73. Then, a TiN film 74, Al-alloy film 75, and Ti film 76 are deposited on the silicon oxide film 64 including the surface of the plug 73 by the sputtering method and thereafter, the Ti film 76, Al-alloy film 75, and TiN film 74 are patterned to form second-layer wirings 77 and 78.
    Type: Grant
    Filed: January 11, 2000
    Date of Patent: December 10, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Yoshitaka Nakamura, Tsuyoshi Tamaru, Naoki Fukuda, Hidekazu Goto, Isamu Asano, Hideo Aoki, Keizo Kawakita, Satoru Yamada, Katsuhiko Tanaka, Hiroshi Sakuma, Masayoshi Hirasawa
  • Publication number: 20020182798
    Abstract: In a DRAM having a capacitor-over-bitline structure in which the capacitive insulating film of an information storing capacitive element C is formed of a high dielectric material such as Ta2O5 (tantalum oxide) film 46, the portions of bit lines BL and first-layer interconnect lines 23 to 26 of a peripheral circuit which are in contact with at least an underlying silicon oxide film 28 are formed of a W film, the bit lines BL and the interconnect lines 23 to 26 being arranged below the information storing capacitive element C, whereby the adhesion at the interface between the bit lines BL and the interconnect lines 23 to 26 and the silicon oxide film is improved in terms of high-temperature heat treatment to be performed when the capacitive insulating film is being formed.
    Type: Application
    Filed: May 31, 2002
    Publication date: December 5, 2002
    Inventors: Masayoshi Saito, Yoshitaka Nakamura, Hidekazu Goto, Keizo Kawakita, Satoru Yamada, Toshihiro Sekiguchi, Isamu Asano, Yoshitaka Tadaki, Takuya Fukuda, Masayuki Suzuki, Tsuyoshi Tamaru, Naoki Fukuda, Hideo Aoki, Masayoshi Hirasawa
  • Patent number: 6483136
    Abstract: An active region (L) with a metal insulator semiconductor field effect transistor (MISFET) (Qs) formed therein for selection of a DRAM memory cell, which makes up a memory cell of the DRAM, is arranged to have an island-like pattern that linearly extends in an X direction on one principal surface of a semiconductor substrate (1). The memory-cell selection MISFET (Qs) has an insulated gate electrode (7) (word line WL) that extends along a Y direction on the principal surface of the semiconductor substrate (1) with the same width kept along the length thereof, which gate electrode is arranged to oppose another gate electrode (7) (word line WL) adjacent thereto at a prespecified distance or pitch that is narrower than said width.
    Type: Grant
    Filed: April 14, 2000
    Date of Patent: November 19, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Makoto Yoshida, Takahiro Kumauchi, Yoshitaka Tadaki, Isamu Asano, Norio Hasegawa, Keizo Kawakita
  • Publication number: 20020155662
    Abstract: In semiconductor integrated circuit device having a DRAM including a memory cell portion formed at a first portion of a main surface of a semiconductor substrate and a peripheral circuit portion formed at a second portion of the main surface of the semiconductor substrate, bit line conductors and first level interconnect conductors in the peripheral circuit portion for connecting the memory cell portion and the peripheral circuit portion so as to exchange signals between them are constituted by conductor layers that are formed simultaneously and hence, exist at the same level. The conductor layers exist at an outside position of the memory cell portion such as in the peripheral circuit portion, and the thickness of portions of the conductor layers constituting the first level interconnect conductors of the peripheral circuit portion is greater than the thickness of portions of the conductor layers constituting the bit line conductors.
    Type: Application
    Filed: June 11, 2002
    Publication date: October 24, 2002
    Inventors: Isamu Asano, Robert Tsu
  • Publication number: 20020127793
    Abstract: A semiconductor integrated circuit device having a switching MISFET, and a capacitor element formed over the semiconductor substrate, such as a DRAM, is disclosed. In a first aspect of the present invention, the impurity concentration of the semiconductor region of the switching MISFET to which the capacitor element is connected is less than the impurity concentration of semiconductor regions of MISFETs of peripheral circuitry. In a second aspect, the Y-select signal line overlaps the lower electrode layer of the capacitor element. In a third aspect, a potential barrier layer, provided at least under the semiconductor region of the switching MISFET to which the capacitor element is connected, is formed by diffusion of an impurity for a channel stopper region. In a fourth aspect, the dielectric film of the capacitor element is co-extensive with the capacitor electrode layer over it.
    Type: Application
    Filed: December 3, 2001
    Publication date: September 12, 2002
    Inventors: Jun Murata, Yoshitaka Tadaki, Isamu Asano, Mitsuaki Horiuchi, Jun Sugiura, Hiroko Kaneko, Shinji Shimizu, Atsushi Hiraiwa, Hidetsugu Ogishi, Masakazu Sagawa, Masami Ozawa, Toshihiro Sekiguchi
  • Publication number: 20020123190
    Abstract: A semiconductor integrated circuit device and a manufacturing method therefor provide advantages that undulations are prevented from being produced in polycrystal silicon plugs in bit line contact holes and that the undesired phenomenon of transversally etching silicide film at contacts of the bit lines and the polycrystal silicon plugs is avoided. The bit lines formed when forming a first wiring layer are made of a laminate film having a titanium film, a titanium nitride film and a tungsten film, and a titanium silicide film containing nitrogen or oxygen is formed in contact areas of the bit lines and plugs. A titanium silicide film containing nitrogen or oxygen is also formed in contact areas of the first wiring layer and semiconductor substrate. The titanium silicide film may be replaced by silicide film containing nitrogen or oxygen, cobalt silicide film containing nitrogen or oxygen or cobalt silicide film.
    Type: Application
    Filed: May 3, 2002
    Publication date: September 5, 2002
    Inventors: Yoshitaka Nakamura, Hideo Aoki, Yoshikazu Ohira, Tadashi Umezawa, Satoru Yamada, Keizou Kawakita, Isamu Asano, Naoki Fukuda, Tsuyoshi Tamaru, Hidekazu Goto, Nobuyoshi Kobayashi
  • Patent number: 6426255
    Abstract: After formation of a groove in a silicon oxide film, a Pt film is formed inside of the groove by electroplating using a conductive underlying film, which has been formed in advance below the silicon oxide film, as a cathode electrode. The silicon oxide film is then removed by etching, followed by dry etching of the conductive underlying film with the Pt film as a mask, whereby a lower electrode of a capacitor is formed from the Pt film and the conductive underlying film which has remained below the Pt film.
    Type: Grant
    Filed: April 13, 2000
    Date of Patent: July 30, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Isamu Asano, Yoshitaka Nakamura, Yuzuru Ohji, Tatsuyuki Saito, Takashi Yunogami
  • Patent number: 6417045
    Abstract: In semiconductor integrated circuit device having a DRAM including a memory cell portion formed at a first portion of a main surface of a semiconductor substrate and a peripheral circuit portion formed at a second portion of the main surface of the semiconductor substrate, bit line conductors and first level interconnect conductors in the peripheral circuit portion for connecting the memory cell portion and the peripheral circuit portion so as to exchange signals between them are constituted by conductor layers that are formed simultaneously and hence, exist at the same level. The conductor layers exist at an outside position of the memory cell portion such as in the peripheral circuit portion, and the thickness of portions of the conductor layers constituting the first level interconnect conductors of the peripheral circuit portion is greater than the thickness of portions of the conductor layers constituting the bit line conductors.
    Type: Grant
    Filed: August 22, 2000
    Date of Patent: July 9, 2002
    Assignees: Hitachi, Ltd., Texas Instruments Incorporated
    Inventors: Isamu Asano, Robert Tsu