Patents by Inventor Hitoshi Saita

Hitoshi Saita 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: 8498095
    Abstract: A thin-film capacitor that is less prone to generation of internal cracking or peeling is provided. In a thin-film capacitor according to the present embodiment, because through holes H are formed in internal electrodes containing Ni as a principal component in a lamination direction, a surface area of at least some of the through holes H is in the range of 0.19 ?m2 to 7.0 ?m2, and a ratio of a surface area of the through holes H to a surface area of an entire main surface of the internal electrodes is in the range of 0.05% to 5%, peeling or cracking is suppressed from occurring at the boundaries between the internal electrodes and dielectric layers, and as a result, the yield is enhanced.
    Type: Grant
    Filed: November 30, 2010
    Date of Patent: July 30, 2013
    Assignee: TDK Corporation
    Inventors: Yoshihiko Yano, Yasunobu Oikawa, Kenji Horino, Hitoshi Saita
  • Patent number: 8315038
    Abstract: A thin-film capacitor has a high insulation resistance value with high reliability. The thin-film capacitor includes a dielectric thin film and electrodes opposing each other through the dielectric thin film, the dielectric thin film containing a perovskite-type composite oxide having a composition expressed by (1), Mn, and at least one kind of element M selected from V, Nb, and Ta; wherein the dielectric thin film has an Mn content of 0.05 to 0.45 mol with respect to 100 mol of the composite oxide; and wherein the dielectric thin film has a total element M content of 0.05 to 0.5 mol with respect to 100 mol of the composite oxide: AyBO3??(1) where A is at least one kind of element selected from Ba, Sr, Ca, and Pb, B is at least one kind of element selected from Ti, Zr, Hf, and Sn, and 0.97?y?0.995.
    Type: Grant
    Filed: April 8, 2010
    Date of Patent: November 20, 2012
    Assignee: TDK Corporation
    Inventors: Hitoshi Saita, Naoto Tsukamoto, Akira Shibue, Kenji Horino
  • Patent number: 8294036
    Abstract: In a dielectric element, the side faces are roughened so that the surface roughness Ra is 15 nm or greater. By this means, the area of contact between a glass epoxy resin substrate and insulating material is increased, adhesion with resin substrates is improved, and strength and reliability can be enhanced when buried between two resin substrates. In the dielectric element, the surface roughness Ra of side surfaces is 5000 nm or less, so that when burying the dielectric element between a glass epoxy resin substrate and insulating material, the occurrence of air bubbles between the surface of the dielectric element and the resin can be prevented.
    Type: Grant
    Filed: March 25, 2009
    Date of Patent: October 23, 2012
    Assignee: TDK Corporation
    Inventors: Shinichiro Kakei, Kenji Horino, Hitoshi Saita, Yasunobu Oikawa
  • Patent number: 8218287
    Abstract: A thin-film device comprises a base electrode made of a metal, a first dielectric layer, a first inner electrode, a second dielectric layer, a second inner electrode, and a third dielectric layer. Letting T1 be the thickness of the lowermost first dielectric layer in contact with the base electrode in the plurality of dielectric layers, and Tmin be the thickness of the thinnest dielectric layer in the plurality of dielectric layers excluding the first dielectric layer, T1>Tmin. Making the first dielectric layer thicker than the thinnest, dielectric layer in the other dielectric layers can increase the distance between a metal part projecting from a metal surface because of the surface roughness of the base electrode and the inner electrode mounted on the lowermost dielectric layer, thereby reducing leakage currents.
    Type: Grant
    Filed: March 19, 2010
    Date of Patent: July 10, 2012
    Assignee: TDK Corporation
    Inventors: Akira Shibue, Yoshihiko Yano, Hitoshi Saita, Kenji Horino
  • Patent number: 8149584
    Abstract: In a dielectric element, the angle ? made by either the top face or the bottom face and the side faces is either 0°<?<89°, or is 91°<?<180°, and is an angle other than 89°???91°. By this means, the area of contact of the side faces of the dielectric element with a glass epoxy resin substrate and with insulating material is increased, adhesion with the resin substrates is improved, and strength and reliability can be enhanced when buried between the two resin substrates.
    Type: Grant
    Filed: March 25, 2009
    Date of Patent: April 3, 2012
    Assignee: TDK Corporation
    Inventors: Hitoshi Saita, Kenji Horino, Yasunobu Oikawa, Shinichiro Kakei
  • Publication number: 20110128669
    Abstract: A thin-film capacitor that is less prone to generation of internal cracking or peeling is provided. In a thin-film capacitor 100 according to the present embodiment, because through holes H are formed in internal electrodes 3, 5, 7, and 9 containing Ni as a principal component in a lamination direction, a surface area of at least some of the through holes H is in the range of 0.19 ?m2 to 7.0 ?m2, and a ratio of a surface area of the through holes H to a surface area of an entire main surface of the internal electrodes 3, 5, 7, and 9 is in the range of 0.05% to 5%, peeling or cracking is suppressed from occurring at the boundaries between the internal electrodes 3, 5, 7, and 9 and dielectric layers 2, 4, 6, 8, and 10, and as a result, the yield is enhanced.
    Type: Application
    Filed: November 30, 2010
    Publication date: June 2, 2011
    Applicant: TDK CORPORATION
    Inventors: Yoshihiko YANO, Yasunobu OIKAWA, Kenji HORINO, Hitoshi SAITA
  • Patent number: 7929272
    Abstract: A dielectric device having a dielectric layer and first to nth metal layers (where n is an integer of 2 or greater) in contact with the dielectric layer. At least one of the first to nth metal layers contains a base metal. Interfaces between the first to nth metal layers and the dielectric layer have respective arithmetic mean roughnesses of Ra1 to Ran (nm), while an average value Ram (nm) of the arithmetic mean roughnesses of Ra1 to Ran (nm) and a thickness T (nm) of the dielectric layer satisfy T/Ram ?1.3.
    Type: Grant
    Filed: June 4, 2007
    Date of Patent: April 19, 2011
    Assignee: TDK Corporation
    Inventors: Shinichiro Kakei, Hitoshi Saita, Kuniji Koike, Kenji Horino
  • Patent number: 7883905
    Abstract: It is an object of the invention to provide a process for production of a thin-film capacitor that can simultaneously achieve improved capacity density and reduced leakage current density for barium strontium titanate thin-films. There is provided a process for production of thin-film capacitors that includes a metal oxide thin-film forming step in which an organic dielectric starting material is fired to form a barium strontium titanate thin-film, wherein the firing atmosphere used is an oxygen-containing inert gas atmosphere, and the barium strontium titanate thin-film formed by the process has a larger capacity density than the capacity density of the barium strontium titanate thin-film fired in an oxygen atmosphere.
    Type: Grant
    Filed: July 28, 2006
    Date of Patent: February 8, 2011
    Assignee: TDK Corporation
    Inventors: Hitoshi Saita, Kiyoshi Uchida, Kenji Horino, Eri Aizawa
  • Publication number: 20100265632
    Abstract: The present invention provides a thin-film capacitor having an insulation resistance value higher than that conventionally available and high reliability. The thin-film capacitor of the present invention comprises a dielectric thin film and electrodes opposing each other through the dielectric thin film interposed therebetween; wherein the dielectric thin film contains a perovskite-type composite oxide having a composition expressed by the following chemical formula (1), Mn, and at least one kind of element M selected from the group consisting of V, Nb, and Ta; wherein the dielectric thin film has an Mn content of 0.05 to 0.45 mol with respect to 100 mol of the composite oxide; and wherein the dielectric thin film has a total element M content of 0.05 to 0.
    Type: Application
    Filed: April 8, 2010
    Publication date: October 21, 2010
    Applicant: TDK CORPORATION
    Inventors: Hitoshi SAITA, Naoto TSUKAMOTO, Akira SHIBUE, Kenji HORINO
  • Publication number: 20100246092
    Abstract: A thin-film device comprises a base electrode made of a metal, a first dielectric layer, a first inner electrode, a second dielectric layer, a second inner electrode, and a third dielectric layer. Letting T1 be the thickness of the lowermost first dielectric layer in contact with the base electrode in the plurality of dielectric layers, and Tmin be the thickness of the thinnest dielectric layer in the plurality of dielectric layers excluding the first dielectric layer, T1>Tmin. Making the first dielectric layer thicker than the thinnest, dielectric layer in the other dielectric layers can increase the distance between a metal part projecting from a metal surface because of the surface roughness of the base electrode and the inner electrode mounted on the lowermost dielectric layer, thereby reducing leakage currents.
    Type: Application
    Filed: March 19, 2010
    Publication date: September 30, 2010
    Applicant: TDK Corporation
    Inventors: Akira SHIBUE, Yoshihiko Yano, Hitoshi Saita, Kenji Horino
  • Patent number: 7713877
    Abstract: A dielectric film production process comprising a baking step in which a dielectric film is formed by heating a precursor layer formed on a metal layer, wherein the metal layer contains at least one type of metal selected from the group consisting of Cu, Ni, Al, stainless steel and austenitic nickel-chromium-based superalloy and during at least part of the baking step the precursor layer is heated in a reduced pressure atmosphere.
    Type: Grant
    Filed: August 24, 2006
    Date of Patent: May 11, 2010
    Assignee: TDK Corporation
    Inventors: Yuki Miyamoto, Hitoshi Saita
  • Publication number: 20090246361
    Abstract: The present invention provides a method for manufacturing a dielectric element in which a dielectric film is formed by a chemical solution deposition method, with enhanced tolerance of the dielectric film of wet processes. A method for manufacturing a dielectric element comprises a process of heating a film of a solution of a precursor on a metal layer in an oxidizing atmosphere, to form a calcined film comprising a dielectric material generated from the precursor, and a process of annealing the calcined film to form a dielectric film comprising the dielectric material that has been crystallized. The dielectric material is a metal oxide which forms a perovskite-structure crystal having A sites and B sites. The solution of the precursor comprises an element occupying A sites and an element occupying B sites in the dielectric film, at a molar ratio of the element occupying A sites to the element occupying B sites of 0.85 or higher and 1.00 or lower.
    Type: Application
    Filed: March 24, 2009
    Publication date: October 1, 2009
    Applicant: TDK CORPORATION
    Inventors: Hitoshi SAITA, Naoto TSUKAMOTO, Akira SHIBUE, Kenji HORINO
  • Publication number: 20090242256
    Abstract: In a dielectric element, the angle ? made by either the top face or the bottom face and the side faces is either 0°<?<89°, or is 91°<?<180°, and is an angle other than 89°???91°. By this means, the area of contact of the side faces of the dielectric element with a glass epoxy resin substrate and with insulating material is increased, adhesion with the resin substrates is improved, and strength and reliability can be enhanced when buried between the two resin substrates.
    Type: Application
    Filed: March 25, 2009
    Publication date: October 1, 2009
    Applicant: TDK CORPORATION
    Inventors: Hitoshi Saita, Kenji Horino, Yasunobu Oikawa, Shinichiro Kakei
  • Publication number: 20090242257
    Abstract: In a dielectric element, the side faces are roughened so that the surface roughness Ra is 15 nm or greater. By this means, the area of contact between a glass epoxy resin substrate and insulating material is increased, adhesion with resin substrates is improved, and strength and reliability can be enhanced when buried between two resin substrates. In the dielectric element, the surface roughness Ra of side surfaces is 5000 nm or less, so that when burying the dielectric element between a glass epoxy resin substrate and insulating material, the occurrence of air bubbles between the surface of the dielectric element and the resin can be prevented.
    Type: Application
    Filed: March 25, 2009
    Publication date: October 1, 2009
    Applicant: TDK CORPORATION
    Inventors: Shinichiro KAKEI, Kenji HORINO, Hitoshi SAITA, Yasunobu OIKAWA
  • Patent number: 7561406
    Abstract: A thin film capacitor with high capacity and low leak current is provided. The thin film capacitor includes a nickel substrate with nickel (Ni) purity of 99.99 weight percent or above, and a dielectric layer and an electrode layer disposed in this order on the nickel substrate. The thin film capacitor is typically manufactured as follows. A precursor dielectric layer is formed on a nickel substrate with nickel purity of 99.99 weight percent or above, and is subjected to annealing to form a dielectric layer. The diffusion of impurities from the nickel substrate to the precursor dielectric layer during annealing is suppressed.
    Type: Grant
    Filed: March 29, 2007
    Date of Patent: July 14, 2009
    Assignee: TDK Corporation
    Inventors: Hitoshi Saita, Yuko Saya, Kiyoshi Uchida, Kenji Horino
  • Publication number: 20090176345
    Abstract: It is an object of the invention to provide a process for production of a thin-film capacitor that can simultaneously achieve improved capacity density and reduced leakage current density for barium strontium titanate thin-films. There is provided a process for production of thin-film capacitors that includes a metal oxide thin-film forming step in which an organic dielectric starting material is fired to form a barium strontium titanate thin-film, wherein the firing atmosphere used is an oxygen-containing inert gas atmosphere, and the barium strontium titanate thin-film formed by the process has a larger capacity density than the capacity density of the barium strontium titanate thin-film fired in an oxygen atmosphere.
    Type: Application
    Filed: July 28, 2006
    Publication date: July 9, 2009
    Applicant: TDK CORPORATION
    Inventors: Hitoshi Saita, Kiyoshi Uchida, Kenji Horino, Eri Aizawa
  • Patent number: 7539005
    Abstract: A capacitor provided with a dielectric film, and a first electrode and second electrode formed sandwiching it and facing each other, wherein the dielectric film has a density exceeding 72% of the theoretical density calculated based on the lattice constant, and either or both of said first electrode and said second electrode contain at least one metal selected from the group consisting of Cu, Ni, Al, stainless steel and a nickel-based alloy.
    Type: Grant
    Filed: July 26, 2006
    Date of Patent: May 26, 2009
    Assignee: TDK Corporation
    Inventors: Kiyoshi Uchida, Kenji Horino, Hitoshi Saita
  • Patent number: 7382013
    Abstract: To provide a dielectric thin with a high dielectric constant, a low leakage current, and stable physical properties and electrical properties and to provide a thin film capacitor or other thin film dielectric device with a high capacitance and high reliability and a method of production of the same, a dielectric thin film containing oxides such as barium strontium titanate expressed by the formula (BaxSr(1-x))aTiO3 (0.5<x?1.0, 0.96<a?1.00) and having a thickness of not more than 500 nm and a method of production of a thin film dielectric device including a step of annealing the dielectric thin film in an atmosphere of an oxidizing gas after forming a dielectric thin film on a conductive electrode.
    Type: Grant
    Filed: September 28, 2005
    Date of Patent: June 3, 2008
    Assignee: TDK Corporation
    Inventors: Kiyoshi Uchida, Kenji Horino, Hitoshi Saita
  • Publication number: 20070278627
    Abstract: A dielectric device comprises a dielectric layer and first to nth metal layers (where n is an integer of 2 or greater) in contact with the dielectric layer. At least one of the first to nth metal layers contains a base metal. Interfaces between the first to nth metal layers and the dielectric layer have respective arithmetic mean roughnesses of Ra1 to Ran (nm), while an average value Ram (nm) of the arithmetic mean roughnesses of Ra1 to Ran (nm) and a thickness T (nm) of the dielectric layer satisfy T/Ram?1.3.
    Type: Application
    Filed: June 4, 2007
    Publication date: December 6, 2007
    Applicant: TDK CORPORATION
    Inventors: Shinichiro Kakei, Hitoshi Saita, Kuniji Koike, Kenji Horino
  • Publication number: 20070230086
    Abstract: A thin film capacitor with high capacity and low leak current is provided. The thin film capacitor includes a nickel substrate with nickel (Ni) purity of 99.99 weight percent or above, and a dielectric layer and an electrode layer disposed in this order on the nickel substrate. The thin film capacitor is typically manufactured as follows. A precursor dielectric layer is formed on a nickel substrate with nickel purity of 99.99 weight percent or above, and is subjected to annealing to form a dielectric layer. The diffusion of impurities from the nickel substrate to the precursor dielectric layer during annealing is suppressed.
    Type: Application
    Filed: March 29, 2007
    Publication date: October 4, 2007
    Applicant: TDK CORPORATION
    Inventors: Hitoshi Saita, Yuko Saya, Kiyoshi Uchida, Kenji Horino