Patents by Inventor Tetsuro Makita

Tetsuro Makita 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: 6420191
    Abstract: A semiconductor device such as DRAM including a capacitor, wherein a lower electrode of the capacitor is a metal electrode, the metal electrode being mainly composed of ruthenium or iridium, and being connected directly to a capacitor dielectric film through no oxide layer of materials of the metal electrode formed on the surface of the metal electrode. The lower electrode made of iridium or ruthenium can easily be processed as compared with the conventional case where platinum is employed to form the electrode and also can not be oxidized when the capacitor dielectric film is formed, thus reduction in the capacitance can be prevented.
    Type: Grant
    Filed: January 25, 2001
    Date of Patent: July 16, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takeharu Kuroiwa, Tsuyoshi Horikawa, Tetsuro Makita, Noboru Mikami, Teruo Shibano
  • Publication number: 20010009282
    Abstract: A semiconductor device such as DRAM including a capacitor, wherein a lower electrode of the capacitor is a metal electrode, the metal electrode being mainly composed of ruthenium or iridium, and being connected directly to a capacitor dielectric film through no oxide layer of materials of the metal electrode formed on the surface of the metal electrode. The lower electrode made of iridium or ruthenium can easily be processed as compared with the conventional case where platinum is employed to form the electrode and also can not be oxidized when the capacitor dielectric film is formed, thus reduction in the capacitance can be prevented.
    Type: Application
    Filed: January 25, 2001
    Publication date: July 26, 2001
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takeharu Kuroiwa, Tsuyoshi Horikawa, Tetsuro Makita, Noboru Mikami, Teruo Shibano
  • Patent number: 6239460
    Abstract: A semiconductor device such as DRAM including a capacitor, wherein a lower electrode of the capacitor is a metal electrode, the metal electrode being mainly composed of ruthenium or iridium, and being connected directly to a capacitor dielectric film through no oxide layer of materials of the metal electrode formed on the surface of the metal electrode. The lower electrode made of iridium or ruthenium can easily be processed as compared with the conventional case where platinum is employed to form the electrode and also can not be oxidized when the capacitor dielectric film is formed, thus reduction in the capacitance can be prevented.
    Type: Grant
    Filed: June 28, 1996
    Date of Patent: May 29, 2001
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takeharu Kuroiwa, Tsuyoshi Horikawa, Tetsuro Makita, Noboru Mikami, Teruo Shibano
  • Patent number: 6187622
    Abstract: A semiconductor memory device achieves a high capacitance value even when the elements are made extremely small as the degree of integration is increased. A method of producing such a semiconductor memory maintains a high capacitance value while achieving increased integration. A semiconductor memory device includes adjacent capacitor lower electrodes which are separated by a width of 0.2 &mgr;m while the ratio of the capacitor lower electrode height to the separation width is 1, the capacitor upper electrode covers the capacitor insulation film, and steps generated in the separated portion of the capacitor lower electrodes are filled by the upper electrode material. A method of manufacturing produces a semiconductor memory device wherein the capacitor upper electrode is formed in plasma which includes etchable gas by chemical or physical action.
    Type: Grant
    Filed: January 6, 1998
    Date of Patent: February 13, 2001
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takeharu Kuroiwa, Tsuyoshi Horikawa, Noboru Mikami, Tetsuro Makita
  • Patent number: 6165556
    Abstract: There is provided a (Ba, Sr) TiO.sub.3 film of higher dielectric constant and less leakage current for serving as a dielectric thin film of a capacitor in a semiconductor memory. DPM (dipivaloylmethanato) compounds of Ba, Sr and Ti are dissolved in THF (tetrahydrofuran) to obtain Ba(DPM).sub.2 /THF, Sr(DPM).sub.2 /THF and TiO(DPM).sub.2 /THF solutions which are used as source material solutions. A (Ba, Sr) TiO.sub.3 film is formed by a CVD method while increasing a relative percentage of a Ti source material flow rate to a sum of Ba source material flow rate and Sr source material flow rate. The film formation is carried out in multiple steps, and annealing is applied in each step after deposition of the film.
    Type: Grant
    Filed: November 8, 1999
    Date of Patent: December 26, 2000
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takaaki Kawahara, Mikio Yamamuka, Tetsuro Makita, Tsuyoshi Horikawa, Akimasa Yuuki, Teruo Shibano
  • Patent number: 6101085
    Abstract: There is provided a (Ba, Sr) TiO.sub.3 film of higher dielectric constant and less leakage current for serving as a dielectric thin film of a capacitor in a semiconductor memory. DPM (dipivaloylmethanato) compounds of Ba, Sr and Ti are dissolved in THF (tetrahydrofuran) to obtain Ba(DPM).sub.2 /THF, Sr(DPM).sub.2 /THF and TiO(DPM).sub.2 /THF solutions which are used as source material solutions. A (Ba, Sr) TiO.sub.3 film is formed by a CVD method while increasing a relative percentage of a Ti source material flow rate to a sum of Ba source material flow rate and Sr source material flow rate. The film formation is carried out in multiple steps, and annealing is applied in each step after deposition of the film.
    Type: Grant
    Filed: September 12, 1997
    Date of Patent: August 8, 2000
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takaaki Kawahara, Mikio Yamamuka, Tetsuro Makita, Tsuyoshi Horikawa, Akimasa Yuuki, Teruo Shibano
  • Patent number: 6096133
    Abstract: An apparatus for depositing a thin film on a substrate by chemical vapor deposition (CVD) includes a material container for containing a liquid CVD source material; a material feeder for feeding the liquid CVD source material from the material container to a vaporizer while keeping the CVD source material liquid; a vaporizer for vaporizing the liquid CVD source material fed from the material feeder by heating the liquid CVD source material to a high temperature to form a CVD source material gas; a reaction chamber connected to the vaporizer by a pipe for forming a thin film on a substrate using the CVD source material gas; and a thermostatic box surrounding the reaction chamber, wherein both of the vaporizer and piping connecting the vaporizer to the reaction chamber are located within the thermostatic box.
    Type: Grant
    Filed: January 6, 2000
    Date of Patent: August 1, 2000
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Akimasa Yuuki, Takaaki Kawahara, Tetsuro Makita, Mikio Yamamuka, Koichi Ono, Tomonori Okudaira
  • Patent number: 6049103
    Abstract: A thin film capacitor structure of a random access memory includes plurality of capacitors formed on an interlayer insulating film. The capacitor structure includes a plurality of lower electrodes formed on the interlayer insulating film, a first dielectric film formed over the plurality of lower electrodes and portions of the interlayer insulating film between lower electrodes, a second dielectric film formed on the first dielectric film, and an upper electrode formed on the second dielectric layer. A silicon oxide film is formed at the step portions of the first dielectric film which result at the periphery of the lower electrodes to prevent leakage current between adjacent capacitors.
    Type: Grant
    Filed: March 22, 1996
    Date of Patent: April 11, 2000
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tsuyoshi Horikawa, Yoshikazu Tsunemine, Takeharu Kuroiwa, Tetsuro Makita, Noboru Mikami
  • Patent number: 6033732
    Abstract: A method of depositing a thin film on a substrate by chemical vapor deposition (CVD) including feeding a liquid CVD source material, including a solution in which at least one organometallic complex is dissolved in a solvent, at a constant flow rate to a vaporizer while keeping the CVD source material in a liquid state; vaporizing the liquid CVD source material by heating to form a CVD source material gas; and forming a thin film of a metal oxide on a substrate using the CVD material source gas in a reaction chamber, the thin film including at least titanium, including using TTIP and TiO(Dpm).sub.2 together as the organometallic complex.
    Type: Grant
    Filed: April 30, 1998
    Date of Patent: March 7, 2000
    Assignee: Mitsushita Denki Kabushiki Kaisha
    Inventors: Akimasa Yuuki, Takaaki Kawahara, Tetsuro Makita, Mikio Yamamuka, Koichi Ono, Tomonori Okudaira
  • Patent number: 6015989
    Abstract: A semiconductor device includes a semiconductor substrate having a major surface; a first interlayer insulating film formed on the semiconductor substrate and having an opening defined therein so as to open at the major surface of the semiconductor substrate; a connecting member made of Si as a principal component and embedded in the opening; a lower capacitor electrode connected electrically with the major surface of the semiconductor substrate through the connecting member; a capacitor dielectric film formed on the lower capacitor electrode; an upper capacitor electrode formed on the capacitor dielectric film; and a second interlayer insulating film formed on the capacitor upper electrode. The lower capacitor electrode referred to above is made of a principal component selected from the group consisting of ruthenium and iridium and contains oxygen in a quantity of 0.001 to 0.1% by atom and/or at least one impurity element in a quantity of 0.1 to 5% by atom.
    Type: Grant
    Filed: December 20, 1996
    Date of Patent: January 18, 2000
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tsuyosi Horikawa, Tetsuro Makita, Takeharu Kuroiwa, Noboru Mikami, Teruo Shibano
  • Patent number: 5989635
    Abstract: There is provided a (Ba, Sr) TiO.sub.3 film of higher dielectric constant and less leakage current for serving as a dielectric thin film of a capacitor in a semiconductor memory. DPM (dipivaloylmethanato) compounds of Ba, Sr and Ti are dissolved in THF (tetrahydrofuran) to obtain Ba(DPM).sub.2 /THF, Sr(DPM).sub.2 /THF and TiO(DPM).sub.2 /THF solutions which are used as source material solutions. A (Ba, Sr) TiO.sub.3 film is formed by a CVD method while increasing a relative percentage of a Ti source material flow rate to a sum of Ba source material flow rate and Sr source material flow rate. The film formation is carried out in multiple steps, and annealing is applied in each step after deposition of the film.
    Type: Grant
    Filed: September 12, 1997
    Date of Patent: November 23, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takaaki Kawahara, Mikio Yamamuka, Tetsuro Makita, Tsuyoshi Horikawa, Akimasa Yuuki, Teruo Shibano
  • Patent number: 5939744
    Abstract: In a thin film capacitor of a random access memory including a lower electrode, a dielectric film and an upper electrode, generation of defects in the dielectric film is suppressed. In another way, impurity diffusion into the dielectric film is prevented. In still another way, lattice matching of the dielectric film and the electrodes is realized. Thus, a reduced dielectric constant of the capacitor is prevented, and a quality of the semiconductor device is increased.
    Type: Grant
    Filed: October 17, 1997
    Date of Patent: August 17, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tsuyoshi Horikawa, Yoshikazu Tsunemine, Takeharu Kuroiwa, Tetsuro Makita, Noboru Mikami
  • Patent number: 5882410
    Abstract: There is provided a (Ba, Sr) TiO.sub.3 film of higher dielectric constant and less leakage current for serving as a dielectric thin film of a capacitor in a semiconductor memory. DPM (dipivaloylmethanato) compounds of Ba, Sr and Ti are dissolved in THF (tetrahydrofuran) to obtain Ba(DPM).sub.2 /THF, Sr(DPM).sub.2 /THF and TiO(DPM).sub.2 /THF solutions which are used as source material solutions. A (Ba, Sr) TiO.sub.3 film is formed by a CVD method while increasing a relative percentage of a Ti source material flow rate to a sum of Ba source material flow rate and Sr source material flow rate. The film formation is carried out in multiple steps, and annealing is applied in each step after deposition of the film.
    Type: Grant
    Filed: July 15, 1998
    Date of Patent: March 16, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takaaki Kawahara, Mikio Yamamuka, Tetsuro Makita, Tsuyoshi Horikawa, Akimasa Yuuki, Teruo Shibano
  • Patent number: 5834060
    Abstract: There is provided a (Ba, Sr) TiO.sub.3 film of higher dielectric constant and less leakage current for serving as a dielectric thin film of a capacitor in a semiconductor memory. DPM (dipivaloylmethanato) compounds of Ba, Sr and Ti are dissolved in THF (tetrahydrofuran) to obtain Ba(DPM).sub.2 /THF, Sr(DPM).sub.2 /THF and TiO(DPM).sub.2 /THF solutions which are used as source material solutions. A (Ba, Sr) TiO.sub.3 film is formed by a CVD method while increasing a relative percentage of a Ti source material flow rate to a sum of Ba source material flow rate and Sr source material flow rate. The film formation is carried out in multiple steps, and annealing is applied in each step after deposition of the film.
    Type: Grant
    Filed: October 1, 1996
    Date of Patent: November 10, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takaaki Kawahara, Mikio Yamamuka, Tetsuro Makita, Tsuyoshi Horikawa, Akimasa Yuuki, Teruo Shibano
  • Patent number: 5776254
    Abstract: A chemical vapor deposition (CVD) apparatus for depositing a thin film on a substrate by CVD has a material container for containing a liquid CVD source material, a material feeder for feeding the liquid CVD source material to a vaporizer for vaporizing the liquid CVD source material, and a reaction chamber for forming the thin film on the substrate using the CVD source material gas. Both the vaporizer and piping between the vaporizer and the reaction chamber are located in a thermostatic box surrounding the reaction chamber. Thus, the structure of the apparatus is simplified and also the heat efficiency of the apparatus is improved.
    Type: Grant
    Filed: December 27, 1995
    Date of Patent: July 7, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Akimasa Yuuki, Takaaki Kawahara, Tetsuro Makita, Mikio Yamamuka, Koichi Ono, Tomonori Okudaira
  • Patent number: 5293262
    Abstract: In a liquid crystal display device with a drive circuit board connected to the peripheral portion of a liquid crystal display panel, the circuit board is disposed behind the liquid crystal display panel and also the circuit board is connected with the liquid crystal display panel by means of a connecting member in film form, whereby the liquid crystal display device is miniaturized and efficiency of the assembly work is improved. Further, the circuit board is made up of plural drive circuit modules of the same type whereby the efficiency in the assembly and inspection process is still improved.
    Type: Grant
    Filed: August 17, 1992
    Date of Patent: March 8, 1994
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kohei Adachi, Hideaki Otsuki, Kenichi Niki, Hayato Takasago, Tetsuro Makita
  • Patent number: 5029984
    Abstract: In a liquid crystal display device with a drive circuit board connected to the peripheral portion of a liquid crystal display panel, the circuit board is disposed behind the liquid crystal display panel and also the circuit board is connected with the liquid crystal display panel by means of a connecting member in film form, whereby the liquid crystal display device is miniaturized and efficiency of the assembly work is improved. Further, the circuit board is made up of plural drive circuit modules of the same type whereby the efficiency in the assembly and inspection process is still improved.
    Type: Grant
    Filed: February 8, 1989
    Date of Patent: July 9, 1991
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kohei Adachi, Hideaki Otsuki, Kenichi Niki, Hayato Takasago, Tetsuro Makita
  • Patent number: 4854230
    Abstract: A screen printing apparatus comprising a screen having an opening or openings of a desired print pattern and having a lower surface being positioned adjacent to a substrate to be printed, and a nonflexible squeegee comprising a cavity for containing a material to be printed on the substrate. The cavity is defined by the interior surfaces of surrounding walls extending generally vertically from the lower extremities at which the squeegee directly contacts the upper surface of the screen. While the squeegee travels with respect to the screen the material to be printed flows from the cavity into the openings of the screen, and thereby onto the substrate. The squeegee may be formed of stainless steel, a ceramic material or a synthetic resin.
    Type: Grant
    Filed: May 11, 1988
    Date of Patent: August 8, 1989
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kenichi Niki, Tetsuro Makita, Hayato Takasago