Patents by Inventor Takeo Shiba

Takeo Shiba 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: 6861299
    Abstract: Inexpensive, unannealed glass is used as a substrate. The surface of a polycrystalline silicon film doped with boron (B) or phosphorus (P) is oxidized with ozone at a processing temperature of 500° C. or below to form a silicon oxide film of 4 to 20 nm thick on the surface of polycrystalline silicon. On account of this treatment, the level density at the interface between the gate-insulating layer and the channel layer can be made lower, and a thin-film transistor having less variations of characteristics can be formed on the unannealed glass substrate.
    Type: Grant
    Filed: April 2, 2003
    Date of Patent: March 1, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Kazuhiko Horikoshi, Klyoshi Ogata, Takuo Tamura, Miwako Nakahara, Makoto Ohkura, Ryoji Oritsuki, Yasushi Nakano, Takeo Shiba
  • Patent number: 6847069
    Abstract: A thin-film semiconductor device is provided in which an island region of an isolated single-crystal thin-film is formed on an entire surface or within a specific region of an insulating film by utilizing cohesion phenomena due to the surface tension of a melted semiconductor, wherein more than one active region of a thin-film transistor is formed in the island region.
    Type: Grant
    Filed: February 26, 2003
    Date of Patent: January 25, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Seong-Kee Park, Shinya Yamaguchi, Mutsuko Hatano, Takeo Shiba
  • Publication number: 20050007316
    Abstract: Disclosed herewith an image display device capable of displaying high quality images and preferred for reducing the manufacturing cost. The image display device is provided with illuminating state controlling state for controlling the illuminating state or non-illuminating state and constant voltage supply for supplying a constant voltage to each pixel through a signal line when the illuminating state is selected for the pixel.
    Type: Application
    Filed: January 15, 2004
    Publication date: January 13, 2005
    Inventors: Hajime Akimoto, Hiroshi Kageyama, Takeo Shiba
  • Patent number: 6835632
    Abstract: The present invention provides a polycrystalline silicon conducting structure (e.g., a resistor) whose resistance value is controlled, and can be less variable and less dependent on temperature with respect to any resistant value, and a process of producing the same. Use is made of at least a two-layer structure including a first polycrystalline silicon layer of large crystal grain size and a second polycrystalline silicon layer of small crystal grain size, and the first polycrystalline silicon layer has a positive temperature dependence of resistance while the second polycrystalline silicon layer has a negative temperature dependence of resistance, or vice versa. Moreover, the polycrystalline silicon layer of large grain size can be formed by high dose ion implantation and annealing, or by depositing the layers by chemical vapor deposition at different temperatures so as to form large-grain and small-grain layers.
    Type: Grant
    Filed: June 13, 2003
    Date of Patent: December 28, 2004
    Assignees: Hitachi, Ltd., Hitachi Device Engineering Co., Ltd.
    Inventors: Hiromi Shimamoto, Takashi Uchino, Takeo Shiba, Kazuhiro Ohnishi, Yoichi Tamaki, Takashi Kobayashi, Toshiyuki Kikuchi, Takahide Ikeda
  • Publication number: 20040257486
    Abstract: A large number of pixels PXL are arranged in a matrix fashion in a display region DSP on an insulating substrate. Disposed around the display region DSP are a drain-side pixel-driving circuit including a drain shift register DSR, a digital-to-analog converter circuit DAC, a drain level shifter DLS, a buffer BF and sampling switches SSW; and a gate-side pixel-driving circuit including a gate shift register GSR and a gate level shifter GLS, and various kinds of circuits. Current mobility of thin film transistors constituting a circuit region SX requiring high-speed operation of these pixel-driving circuits is improved by optimizing a combination of plural layouts, arrangements and configurations for the respective circuits to meet the specifications special for the respective circuits.
    Type: Application
    Filed: February 6, 2004
    Publication date: December 23, 2004
    Applicants: Hitachi., Ltd. and, Hitachi Displays, Ltd.
    Inventors: Mitsuharu Tai, Mutsuko Hatano, Shinya Yamaguchi, Takeo Shiba, Hideo Sato
  • Publication number: 20040258866
    Abstract: The image display device has a display section formed of plural pixels and a control section which controls the display section, and is provided with nonvolatile phase-change type pixel memories in respective ones of the pixels, or is provided with a nonvolatile phase-change type frame memory in the control section. Each of the nonvolatile phase-change type pixel memories is formed of one or more switches and a variable-resistance memory element fabricated from a chalcogenide material for storing display data for at least a specified period of time. The nonvolatile phase-change type frame memory is formed of one or more switches and a variable-resistance memory element fabricated from a chalcogenide material for retaining display data for one frame.
    Type: Application
    Filed: February 6, 2004
    Publication date: December 23, 2004
    Applicants: Hitachi., Ltd., Hitachi Displays, Ltd.
    Inventors: Takeo Shiba, Motoyasu Terao, Hideyuki Matsuoka
  • Patent number: 6806099
    Abstract: The present invention provides a process for producing a polycrystal silicon film which comprises a step of forming a polycrystal silicon film by light irraditation of a silicon film set on a substrate, and a step of selecting substrate samples having an average grain size in a plane of the sample of 500 nm or more. According to the present invention, stable production of a high-performance poly-silicon TFT liquid crystal display becomes possible.
    Type: Grant
    Filed: January 31, 2002
    Date of Patent: October 19, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Kazuo Takeda, Masakazu Saito, Yukio Takasaki, Hironobu Abe, Makoto Ohkura, Yoshinobu Kimura, Takeo Shiba
  • Publication number: 20040185605
    Abstract: An image display device which includes a display pixel block and circuit blocks peripheral thereto. Each block has a circuit made of high-performance thin film transistors. The display pixel block and the peripheral circuit blocks including the four corners of the display device are formed on an image display device substrate of circuit-built-in type thin film transistors having a small circuit occupation surface area. A circuit including thin film transistors of a polycrystalline silicon film anisotropically crystal-grown and having crystal grains aligned in its longitudinal direction with a current direction is provided in the whole or partial surface of the display pixel block and circuit blocks. The longitudinal direction is aligned with a horizontal or vertical direction within the block, and blocks aligned in the horizontal and vertical directions can be arranged as mixed when viewed from an identical straight line.
    Type: Application
    Filed: February 17, 2004
    Publication date: September 23, 2004
    Applicant: Hitachi, Ltd.
    Inventors: Takeo Shiba, Mutsuko Hatano, Shinya Yamaguchi, Seong-kee Park
  • Publication number: 20040082090
    Abstract: There is provided a method for fabricating an image display device having an active matrix substrate including high-performance transistor circuits operating with high mobility as drive circuits for driving pixel portions which are arranged as a matrix. The portion of a polysilicon film formed in a drive circuit region DAR1 provided on the periphery of the pixel region PAR of the active matrix substrate SUB1 composing the image display device is irradiated and scanned with a pulse modulated laser beam or a pseudo CW laser beam to be reformed into a quasi-strip-like-crystal silicon film having a crystal boundary continuous in the scanning direction so that discrete reformed regions each composed of the quasi-strip-like-crystal silicon film are formed.
    Type: Application
    Filed: June 25, 2003
    Publication date: April 29, 2004
    Applicant: Hitachi, Ltd.
    Inventors: Mutsuko Hatano, Shinya Yamaguchi, Takeo Shiba, Mitsuharu Tai, Hajime Akimoto
  • Patent number: 6716726
    Abstract: The present invention relates to a thin film transistor, in a low-temperature poly-Si thin film becoming an elemental material of the thin film transistor, an object of the invention is to provide the thin film transistor suitable for realizing an image display device having a high performance and a large area at low cost by realizing a poly-crystalline thin film having a crystal structure restraining current scattering in a grain boundary, lessening surface roughness, and capable of realizing high mobility even to a positive hole current.
    Type: Grant
    Filed: October 22, 2002
    Date of Patent: April 6, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Shinya Yamaguchi, Takeo Shiba, Mutsuko Hatano, Seong-Kee Park
  • Publication number: 20040060504
    Abstract: Improving the laser annealing method which is the process of polycrystallizing amorphous silicon, thereby forming with a high throughput silicon thin film in which the crystal particle diameter is sufficiently large. In a process of crystallization by irradiation of a semiconductor thin film formed on a substrate with pulsed laser light, one produces a semiconductor thin film which comprises having a means to shape laser light into a linear beam and a means to periodically and spatially modulate the intensity of pulsed laser in the direction of the long axis of the linear beam by passing through a phase-shifting stripy pattern perpendicular to the long axis, and collectively forming for each shot a polycrystalline film composed of crystals which have grown in a certain direction over the entire region irradiated with the linear beam. The crystal grain size is ½ of the hillock interval.
    Type: Application
    Filed: June 17, 2003
    Publication date: April 1, 2004
    Applicant: Hitachi, Ltd.
    Inventors: Kazuo Takeda, Jun Gotou, Masakazu Saito, Makoto Ohkura, Takeshi Satou, Hiroshi Fukuda, Takeo Shiba
  • Patent number: 6713324
    Abstract: An image display device which includes a display pixel block and circuit blocks peripheral thereto. Each block has a circuit made of high-performance thin film transistors. The display pixel block and the peripheral circuit blocks including the four corners of the display device are formed on an image display device substrate of circuit-built-in type thin film transistors having a small circuit occupation surface area. A circuit including thin film transistors of a polycrystalline silicon film anisotropically crystal-grown and having crystal grains aligned in its longitudinal direction with a current direction is provided in the whole or partial surface of the display pixel block and circuit blocks. The longitudinal direction is aligned with a horizontal or vertical direction within the block, and blocks aligned in the horizontal and vertical directions can be arranged as mixed when viewed from an identical straight line.
    Type: Grant
    Filed: July 3, 2002
    Date of Patent: March 30, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Takeo Shiba, Mutsuko Hatano, Shinya Yamaguchi, Seong-kee Park
  • Patent number: 6690064
    Abstract: A thin film transistor is provided containing polycrystalline Si—Ge alloy. A high performance TFT may be provided having crystal structure restraining both current scattering in a grain boundary and surface roughness by introduction of Ge into Si. An image display device may be realized having a high performance and a large area at a low cost.
    Type: Grant
    Filed: October 22, 2002
    Date of Patent: February 10, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Shinya Yamaguchi, Takeo Shiba, Mutsuko Hatano, Seong-Kee Park
  • Publication number: 20040017365
    Abstract: An image display device has an active matrix substrate provided with a drive circuit formed of high-performance active elements such as thin film transistors which operate with high mobility for driving pixel sections arranged in a matrix configuration. The image display device has discontinuous converted regions (virtual tiles) TL formed of roughly-band-shaped-crystal silicon films in circuit sections constituting a drive circuit DDR disposed around a pixel region PAR on the active matrix substrate SUB1, and has the drive circuit DDR formed of active elements such as thin film transistors fabricated in the discontinuous converted regions TL with their channel direction in a direction of growth direction of the roughly-band-shaped-crystal silicon films.
    Type: Application
    Filed: June 24, 2003
    Publication date: January 29, 2004
    Applicant: Hitachi, Ltd.
    Inventors: Mutsuko Hatano, Shinya Yamaguchi, Takeo Shiba, Mitsuharu Tai, Hajime Akimoto
  • Publication number: 20040005747
    Abstract: A thin-film semiconductor device is such that an island region of an isolated single-crystal thin-film is formed on an entire surface or within a specific region of an insulating film by utilizing cohesion phenomena due to the surface tension of a melted semiconductor, wherein more than one active region of a thin-film transistor is formed in this island region.
    Type: Application
    Filed: February 26, 2003
    Publication date: January 8, 2004
    Inventors: Seong-Kee Park, Shinya Yamaguchi, Mutsuko Hatano, Takeo Shiba
  • Publication number: 20030213957
    Abstract: In a thin film semiconductor device according to the present invention, a continuous oscillating light beam from a solid laser or the like is modulated on time axis and spatially, thereby realizing crystal growth that is nearly optimum for a crystal structure and a growth speed of crystals in a Sin thin film. Crystal grains with a large diameter, flatness with no projections at their grain boundaries, and controlled surface orientations are thereby formed. By forming channels with these crystal grains, high-mobility semiconductor devices and an image display device using these semiconductor devices are realized.
    Type: Application
    Filed: May 16, 2003
    Publication date: November 20, 2003
    Inventors: Shinya Yamaguchi, Mutsuko Hatano, Mitsuharu Tai, Sedng-Kee Park, Takeo Shiba
  • Publication number: 20030207544
    Abstract: The present invention provides a polycrystalline silicon conducting structure (e.g., a resistor) whose resistance value is controlled, and can be less variable and less dependent on temperature with respect to any resistant value, and a process of producing the same. Use is made of at least a two-layer structure including a first polycrystalline silicon layer of large crystal grain size and a second polycrystalline silicon layer of small crystal grain size, and the first polycrystalline silicon layer has a positive temperature dependence of resistance while the second polycrystalline silicon layer has a negative temperature dependence of resistance, or vice versa. Moreover, the polycrystalline silicon layer of large grain size can be formed by high dose ion implantation and annealing, or by depositing the layers by chemical vapor deposition at different temperatures so as to form large-grain and small-grain layers.
    Type: Application
    Filed: June 13, 2003
    Publication date: November 6, 2003
    Inventors: Hiromi Shimamoto, Takashi Uchino, Takeo Shiba, Kazuhiro Ohnishi, Yoichi Tamaki, Takashi Kobayashi, Toshiyuki Kikuchi, Takahide Ikeda
  • Publication number: 20030197666
    Abstract: An image display device having a group of pixels of two or more types, each pixel including light source whose primary wavelength is specific to the type of the pixel, a generating device for generating analog pixel signals to be input to the group of pixels from input digital pixel data, wherein said generating device having a converter to convert input digital pixel data into different output digital pixel data appropriate for each type of pixel where the output digital pixel data contains more bits than the input digital pixel data; and an input device for inputting the analog pixel signals to the group of pixels, each pixel including a light emission driver for driving the light source according to the analog pixel signal. The organic EL display device has individual R, G, and B light emission elements and enables display in desired colors and controllable tones with reduced packaging area for the components of the organic EL display.
    Type: Application
    Filed: January 13, 2003
    Publication date: October 23, 2003
    Inventors: Hajime Akimoto, Takahiro Nagano, Takeo Shiba
  • Publication number: 20030189205
    Abstract: Inexpensive, unannealed glass is used as a substrate. The surface of a polycrystalline silicon film doped with boron (B) or phosphorus (P) is oxidized with ozone at a processing temperature of 500° C. or below to form a silicon oxide film of 4 to 20 nm thick on the surface of polycrystalline silicon. On account of this treatment, the level density at the interface between the gate-insulating layer and the channel layer can be made lower, and a thin-film transistor having less variations of characteristics can be formed on the unannealed glass substrate.
    Type: Application
    Filed: April 2, 2003
    Publication date: October 9, 2003
    Inventors: Kazuhiko Horikoshi, Klyoshi Ogata, Takuo Tamura, Miwako Nakahara, Makoto Ohkura, Ryoji Oritsuki, Yasushi Nakano, Takeo Shiba
  • Patent number: 6610569
    Abstract: The present invention provides a polycrystalline silicon conducting structure (e.g., a resistor) whose resistance value is controlled, and can be less variable and less dependent on temperature with respect to any resistant value, and a process of producing the same. Use is made of at least a two-layer structure including a first polycrystalline silicon layer of large crystal grain size and a second polycrystalline silicon layer of small crystal grain size, and the polycrystalline first silicon layer has a positive in temperature dependence of resist while the second polycrystalline layer has a negative temperature dependence of resistance, or vice versa. Moreover, the polycrystalline silicon layer of large grain size can be formed by high dose ion implantation and annealing, or by depositing the layers by chemical vapor deposition at different temperatures so as to form large-grain and small-grain layers.
    Type: Grant
    Filed: August 28, 2000
    Date of Patent: August 26, 2003
    Assignees: Hitachi, Ltd., Hitachi Device Engineering Co., Ltd.
    Inventors: Hiromi Shimamoto, Takashi Uchino, Takeo Shiba, Kazuhiro Ohnishi, Yoichi Tamaki, Takashi Kobayashi, Toshiyuki Kikuchi, Takahide Ikeda