Patents by Inventor Tadashi Saga

Tadashi Saga 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: 8012654
    Abstract: A photomask blank is provided comprising an etch stop film which is disposed on a transparent substrate and is resistant to fluorine dry etching and removable by chlorine dry etching, a light-shielding film disposed on the etch stop film and including at least one layer composed of a transition metal/silicon material, and an antireflective film disposed on the light-shielding film. When the light-shielding film is dry etched to form a pattern, pattern size variation arising from pattern density dependency is reduced, so that a photomask is produced at a high accuracy.
    Type: Grant
    Filed: June 22, 2010
    Date of Patent: September 6, 2011
    Assignees: Shin-Etsu Chemical Co., Ltd., Toppan Printing Co., Ltd.
    Inventors: Hiroki Yoshikawa, Yukio Inazuki, Satoshi Okazaki, Takashi Haraguchi, Tadashi Saga, Yosuke Kojima, Kazuaki Chiba, Yuichi Fukushima
  • Patent number: 8007964
    Abstract: A photomask blank to be used as a material for a photomask is provided with a mask pattern having a transparent area and an effectively opaque area to exposure light on a transparent substrate. On the transparent board, one or more layers of light shielding films are formed with or without other film (A) in between, at least one layer (B) which constitutes the light shielding film includes silicon and a transition metal as main component, and a molar ratio of silicon to the transition metal is silicon:metal=4-15:1 (atomic ratio). The photomask provided with the mask pattern having the transparent area and the effectively opaque area to exposure light on the transparent board is also provided.
    Type: Grant
    Filed: February 19, 2010
    Date of Patent: August 30, 2011
    Assignees: Shin-Etsu Chemical Co., Ltd., Toppan Printing Co., Ltd.
    Inventors: Hiroki Yoshikawa, Yukio Inazuki, Satoshi Okazaki, Takashi Haraguchi, Masahide Iwakata, Mikio Takagi, Yuichi Fukushima, Tadashi Saga
  • Patent number: 8003284
    Abstract: A photomask blank is provided comprising an etch stop film which is disposed on a transparent substrate and is resistant to fluorine dry etching and removable by chlorine dry etching, a light-shielding film disposed on the etch stop film and including at least one layer composed of a transition metal/silicon material, and an antireflective film disposed on the light-shielding film. When the light-shielding film is dry etched to form a pattern, pattern size variation arising from pattern density dependency is reduced, so that a photomask is produced at a high accuracy.
    Type: Grant
    Filed: June 22, 2010
    Date of Patent: August 23, 2011
    Assignees: Shin-Etsu Chemical Co., Ltd., Toppan Printing Co., Ltd.
    Inventors: Hiroki Yoshikawa, Yukio Inazuki, Satoshi Okazaki, Takashi Haraguchi, Tadashi Saga, Yosuke Kojima, Kazuaki Chiba, Yuichi Fukushima
  • Patent number: 7989124
    Abstract: A photomask blank comprises a transparent substrate, a light-shielding film deposited on the substrate and comprising a metal or metal compound susceptible to fluorine dry etching, and an etching mask film deposited on the light-shielding film and comprising another metal or metal compound resistant to fluorine dry etching. When the light-shielding film is dry etched to form a pattern, pattern size variation arising from pattern density dependency is reduced, so that a photomask is produced at a high accuracy.
    Type: Grant
    Filed: June 22, 2010
    Date of Patent: August 2, 2011
    Assignees: Toppan Printing Co., Ltd., Shin-Etsu Chemical Co., Ltd.
    Inventors: Hiroki Yoshikawa, Yukio Inazuki, Satoshi Okazaki, Takashi Haraguchi, Tadashi Saga, Yosuke Kojima, Kazuaki Chiba, Yuichi Fukushima
  • Publication number: 20100261099
    Abstract: A photomask blank comprises a transparent substrate, a light-shielding film deposited on the substrate and comprising a metal or metal compound susceptible to fluorine dry etching, and an etching mask film deposited on the light-shielding film and comprising another metal or metal compound resistant to fluorine dry etching. When the light-shielding film is dry etched to form a pattern, pattern size variation arising from pattern density dependency is reduced, so that a photomask is produced at a high accuracy.
    Type: Application
    Filed: June 22, 2010
    Publication date: October 14, 2010
    Inventors: Hiroki Yoshikawa, Yukio Inazuki, Satoshi Okazaki, Takashi Haraguchi, Tadashi Saga, Yosuke Kojima, Kazuaki Chiba, Yuichi Fukushima
  • Publication number: 20100261101
    Abstract: A photomask blank is provided comprising an etch stop film which is disposed on a transparent substrate and is resistant to fluorine dry etching and removable by chlorine dry etching, a light-shielding film disposed on the etch stop film and including at least one layer composed of a transition metal/silicon material, and an antireflective film disposed on the light-shielding film. When the light-shielding film is dry etched to form a pattern, pattern size variation arising from pattern density dependency is reduced, so that a photomask is produced at a high accuracy.
    Type: Application
    Filed: June 22, 2010
    Publication date: October 14, 2010
    Inventors: Hiroki Yoshikawa, Yukio Inazuki, Satoshi Okazaki, Takashi Haraguchi, Tadashi Saga, Yosuke Kojima, Kazuaki Chiba, Yuichi Fukushima
  • Publication number: 20100261100
    Abstract: A photomask blank is provided comprising an etch stop film which is disposed on a transparent substrate and is resistant to fluorine dry etching and removable by chlorine dry etching, a light-shielding film disposed on the etch stop film and including at least one layer composed of a transition metal/silicon material, and an antireflective film disposed on the light-shielding film. When the light-shielding film is dry etched to form a pattern, pattern size variation arising from pattern density dependency is reduced, so that a photomask is produced at a high accuracy.
    Type: Application
    Filed: June 22, 2010
    Publication date: October 14, 2010
    Inventors: Hiroki YOSHIKAWA, Yukio Inazuki, Satoshi Okazaki, Takashi Haraguchi, Tadashi Saga, Yosuke Kojima, Kazuaki Chiba, Yuichi Fukushima
  • Patent number: 7790339
    Abstract: A photomask blank has a light-shielding film composed of a single layer of a material containing a transition metal, silicon and nitrogen or a plurality of layers that include at least one layer made of a material containing a transition metal, silicon and nitrogen, and has one or more chrome-based material film. The high transition metal content ensures electrical conductivity, preventing charge-up in the photomask production process, and also provides sufficient chemical stability to cleaning in photomask production. The light-shielding film has a good resistance to dry etching of the chrome-based material film in the presence of chlorine and oxygen, thus ensuring a high processing accuracy.
    Type: Grant
    Filed: April 19, 2007
    Date of Patent: September 7, 2010
    Assignees: Shin-etsu Chemical Co., Ltd., Toppan Printing Co., Ltd.
    Inventors: Hiroki Yoshikawa, Yukio Inazuki, Satoshi Okazaki, Takashi Haraguchi, Tadashi Saga, Yuichi Fukushima
  • Patent number: 7771893
    Abstract: A light-shielding film for exposure light is formed on one principal plane of a transparent substrate made of quartz or the like that serves as a photomask substrate. The light-shielding film can serve not only as the so-called “light-shielding film” but also as an anti-reflection film. In addition, the light-shielding film has a total thickness of 100 nm or less, 70% or more of which is accounted for by the thickness of a chromium compound that has an optical density (OD) per unit thickness of 0.025 nm?1 for light having a wavelength of 450 nm. In the case where the photomask blank is used for fabricating a mask designed for ArF exposure, the thickness and composition of the light-shielding film are selected in such a manner that the OD of the light-shielding film is 1.2 to 2.3 for 193 or 248 nm wavelength light.
    Type: Grant
    Filed: July 20, 2006
    Date of Patent: August 10, 2010
    Assignees: Shin-Etsu Chemical Co., Ltd., Toppan Printing Co., Ltd.
    Inventors: Hiroki Yoshikawa, Hiroshi Kubota, Yoshinori Kinase, Satoshi Okazaki, Tamotsu Maruyama, Takashi Haraguchi, Masahide Iwakata, Yuichi Fukushima, Tadashi Saga
  • Patent number: 7767366
    Abstract: A photomask blank is provided comprising an etch stop film which is disposed on a transparent substrate and is resistant to fluorine dry etching and removable by chlorine dry etching, a light-shielding film disposed on the etch stop film and including at least one layer composed of a transition metal/silicon material, and an antireflective film disposed on the light-shielding film. When the light-shielding film is dry etched to form a pattern, pattern size variation arising from pattern density dependency is reduced, so that a photomask is produced at a high accuracy.
    Type: Grant
    Filed: March 8, 2007
    Date of Patent: August 3, 2010
    Assignees: Shin-Etsu Chemical Co., Ltd., Toppan Printing Co., Ltd.
    Inventors: Hiroki Yoshikawa, Yukio Inazuki, Satoshi Okazaki, Takashi Haraguchi, Tadashi Saga, Yosuke Kojima, Kazuaki Chiba, Yuichi Fukushima
  • Patent number: 7767367
    Abstract: A photomask blank comprises a transparent substrate, a light-shielding film deposited on the substrate and comprising a metal or metal compound susceptible to fluorine dry etching, and an etching mask film deposited on the light-shielding film and comprising another metal or metal compound resistant to fluorine dry etching. When the light-shielding film is dry etched to form a pattern, pattern size variation arising from pattern density dependency is reduced, so that a photomask is produced at a high accuracy.
    Type: Grant
    Filed: March 8, 2007
    Date of Patent: August 3, 2010
    Assignees: Toppan Printing Co., Ltd., Shin-Etsu Chemical Co., Ltd.
    Inventors: Hiroki Yoshikawa, Yukio Inazuki, Satoshi Okazaki, Takashi Haraguchi, Tadashi Saga, Yosuke Kojima, Kazuaki Chiba, Yuichi Fukushima
  • Publication number: 20100155819
    Abstract: A method of fabricating a semiconductor device, includes forming an element isolation trench by processing a silicon substrate and a film to be processed, and filling the element isolation trench with an insulating film by a thermal CVD method. The thermal CVD method in filling the trench is executed under a film forming condition that the insulating film filling a part of the trench that is level with or is located lower than an upper surface of the silicon substrate has a porosity set so as to be not less than 5% and that the insulating film filling a part of the trench located higher than the upper surface of the silicon substrate has a lower deposition rate than the insulating film filling said part of the trench that is level with or is located lower than the upper surface of the silicon substrate.
    Type: Application
    Filed: September 22, 2009
    Publication date: June 24, 2010
    Inventors: Masayuki OGOSHI, Tadashi SAGA
  • Publication number: 20100143831
    Abstract: A photomask blank to be used as a material for a photomask is provided with a mask pattern having a transparent area and an effectively opaque area to exposure light on a transparent substrate. On the transparent board, one or more layers of light shielding films are formed with or without other film (A) in between, at least one layer (B) which constitutes the light shielding film includes silicon and a transition metal as main component, and a molar ratio of silicon to the transition metal is silicon:metal=4-15:1 (atomic ratio). The photomask provided with the mask pattern having the transparent area and the effectively opaque area to exposure light on the transparent board is also provided.
    Type: Application
    Filed: February 19, 2010
    Publication date: June 10, 2010
    Inventors: Hiroki Yoshikawa, Yukio Inazuki, Satoshi Okazaki, Takashi Haraguchi, Masahide Iwakata, Mikio Takagi, Yuichi Fukushima, Tadashi Saga
  • Patent number: 7691546
    Abstract: A photomask blank to be used as a material for a photomask is provided with a mask pattern having a transparent area and an effectively opaque area to exposure light on a transparent substrate. On the transparent board, one or more layers of light shielding films are formed with or without other film (A) in between, at least one layer (B) which constitutes the light shielding film includes silicon and a transition metal as main component, and a molar ratio of silicon to the transition metal is silicon:metal=4-15:1 (atomic ratio). The photomask provided with the mask pattern having the transparent area and the effectively opaque area to exposure light on the transparent board is also provided.
    Type: Grant
    Filed: September 8, 2005
    Date of Patent: April 6, 2010
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hiroki Yoshikawa, Yukio Inazuki, Satoshi Okazaki, Takashi Haraguchi, Masahide Iwakata, Mikio Takagi, Yuichi Fukushima, Tadashi Saga
  • Patent number: 7625677
    Abstract: A half-tone stacked film is designed so as to have a stacked structure of a first half-tone film and a second half-tone film, and the film thickness d, the refractive index n to exposure light and the extinction coefficient k of these half-tone films are designed so that one of these half-tone films becomes a phase advancement film and the other becomes a phase retardation film. When the film thickness (nm), the refractive index, and the extinction coefficient of the phase advancement film are represented by d(+), n(+) and k(+), respectively; and the film thickness (nm), the refractive index, and the extinction coefficient of the phase retardation film are d(?), n(?), and k(?), respectively; the phase advancement film has the relationship of k(+)>a1·n(+)+b1, and the phase retardation film has the relationship of k(?)<a2·n(?)+b2.
    Type: Grant
    Filed: February 3, 2006
    Date of Patent: December 1, 2009
    Assignees: Shin-Etsu Chemical Co., Ltd., Toppan Printing Co., Ltd.
    Inventors: Hiroki Yoshikawa, Yukio Inazuki, Yoshinori Kinase, Satoshi Okazaki, Motohiko Morita, Tadashi Saga
  • Patent number: 7618753
    Abstract: A metal film is provided as a light shielding layer on one principle surface of a photomask substrate. The metal film cannot be substantially etched by chlorine-based dry etching containing oxygen ((Cl+O)-based dry etching) and can be etched by chlorine-based dry etching not containing oxygen (Cl-based dry etching) and fluorine-based dry etching (F-based dry etching). On the light shielding layer, a metal compound film as an antireflective layer. The metal compound film cannot be substantially etched by chlorine-based dry etching not containing oxygen (Cl based) and can be etched by at least one of chlorine-based dry etching containing oxygen ((Cl+O) based) and fluorine-based dry etching (F based).
    Type: Grant
    Filed: August 10, 2005
    Date of Patent: November 17, 2009
    Assignees: Shin-Etsu Chemical Co., Ltd., Toppan Printing Co., Ltd.
    Inventors: Hiroki Yoshikawa, Yukio Inazuki, Yoshinori Kinase, Satoshi Okazaki, Takashi Haraguchi, Masahide Iwakata, Mikio Takagi, Yuichi Fukushima, Tadashi Saga
  • Patent number: 7598004
    Abstract: For the manufacture of a halftone phase shift mask blank comprising a transparent substrate and a translucent film of one or more layers having a controlled phase and transmittance, at least one layer of the translucent film comprising Si, Mo and Zr at the same time, a target comprising at least Zr and Mo in a molar ratio Zr/Mo between 0.05 and 5 is useful.
    Type: Grant
    Filed: March 30, 2005
    Date of Patent: October 6, 2009
    Assignees: Shin-Etsu Chemical Co., Ltd., Toppan Printing Co., Ltd.
    Inventors: Hiroki Yoshikawa, Toshinobu Ishihara, Satoshi Okazaki, Yukio Inazuki, Tadashi Saga, Kimihiro Okada, Masahide Iwakata, Takashi Haraguchi, Yuichi Fukushima
  • Patent number: 7556892
    Abstract: In a halftone phase shift mask blank comprising a substrate, a light absorbing film, and a phase shifter film, the light absorbing film contains a metal element of Group 4A in a distribution having a higher metal element content in an upper region than in a lower region. Also provided is a halftone phase shift mask blank comprising a transparent substrate and a halftone phase shift film of a single layer or multiple layers having a preselected phase difference and transmittance, wherein at least one layer of the halftone phase shift film contains at least 90 atom % of silicon and a plurality of metal elements, typically Mo and Zr or Hf.
    Type: Grant
    Filed: March 30, 2005
    Date of Patent: July 7, 2009
    Assignees: Shin-Etsu Chemical Co., Ltd., Toppan Printing Co., Ltd.
    Inventors: Kimihiro Okada, Masahide Iwakata, Takashi Haraguchi, Mikio Takagi, Yuichi Fukushima, Hiroki Yoshikawa, Toshinobu Ishihara, Satoshi Okazaki, Yukio Inazuki, Tadashi Saga
  • Publication number: 20090057143
    Abstract: A film-depositing target for use in the manufacture of a halftone phase shift mask blank includes a transparent substrate and a translucent film of one or more layers having a controlled phase and transmittance, at least one layer of the translucent film including silicon, molybdenum and zirconium at the same time as constituent elements, and at least two elements, zirconium and molybdenum in a molar ratio Zr/Mo between 0.05 and 5.
    Type: Application
    Filed: October 28, 2008
    Publication date: March 5, 2009
    Inventors: Hiroki YOSHIKAWA, Toshinobu ISHIHARA, Satoshi OKAZAKI, Yukio INAZUKI, Tadashi SAGA, Kimihiro OKADA, Masahide IWAKATA, Takashi HARAGUCHI, Yuichi FUKUSHIMA
  • Patent number: 7351505
    Abstract: In a phase shift mask blank comprising a phase shift multilayer film on a substrate, the phase shift multilayer film consists of at least one layer of light absorption function film and at least one layer of phase shift function film, and the light absorption function film has an extinction coefficient k which increases as the wavelength changes from 157 nm to 260 nm, and has a thickness of up to 15 nm. The phase shift mask blank has minimized wavelength dependency of transmittance and can be processed with a single dry etching gas.
    Type: Grant
    Filed: October 21, 2004
    Date of Patent: April 1, 2008
    Assignees: Shin-Etsu Chemical Co., Ltd, Toppan Printing Co., Ltd
    Inventors: Hiroki Yoshikawa, Yukio Inazuki, Satoshi Okazaki, Takashi Haraguchi, Yuichi Fukushima, Yoshihiro Ii, Tadashi Saga