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: 7084020
    Abstract: A method of forming 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: December 7, 2004
    Date of Patent: August 1, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Seong-Kee Park, Shinya Yamaguchi, Mutsuko Hatano, Takeo Shiba
  • Publication number: 20060118036
    Abstract: To improve the laser annealing process for polycrystallizing amorphous silicon to form silicon thin films having large crystal particle diameters at a high throughput, the present invention is directed to a process of crystallization by irradiation of a semiconductor thin film formed on a substrate with pulsed laser light. The process 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.
    Type: Application
    Filed: January 31, 2006
    Publication date: June 8, 2006
    Inventors: Kazuo Takeda, Jun Gotou, Masakazu Saito, Makoto Ohkura, Takeshi Satou, Hiroshi Fukuda, Takeo Shiba
  • Patent number: 7022183
    Abstract: To improve the laser annealing process for polycrystallizing amorphous silicon to form silicon thin films having large crystal particle diameters at a high throughput, the present invention is directed to a process of crystallization by irradiation of a semiconductor thin film formed on a substrate with pulsed laser light. The process 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.
    Type: Grant
    Filed: June 17, 2003
    Date of Patent: April 4, 2006
    Assignee: Hiatchi, Ltd.
    Inventors: Kazuo Takeda, Jun Gotou, Masakazu Saito, Makoto Ohkura, Takeshi Satou, Hiroshi Fukuda, Takeo Shiba
  • Publication number: 20050285829
    Abstract: The invention provides an image display device that has an especially satisfactory display quality for animated images, and sufficiently suppresses the irregularities of display quality among pixels. The image display device includes a light emitting drive means that drives a light emitting means, based on an analog display signal inputted to the pixels, and a light emitting control switch for controlling a light-on or light-off of the light emitting means on one end of the light emitting drive means in each pixel.
    Type: Application
    Filed: August 5, 2005
    Publication date: December 29, 2005
    Inventors: Hajime Akimoto, Yoshirou Mikami, Kiyoshige Kinugawa, Shigeyuki Nishitani, Takeo Shiba
  • Patent number: 6969871
    Abstract: In a 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 growth speed of crystals in a Si 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: Grant
    Filed: May 16, 2003
    Date of Patent: November 29, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Shinya Yamaguchi, Mutsuko Hatano, Mitsuharu Tai, Sedng-Kee Park, Takeo Shiba
  • Publication number: 20050255679
    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 Si 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: July 22, 2005
    Publication date: November 17, 2005
    Inventors: Shinya Yamaguchi, Mutsuko Hatano, Mitsuharu Tai, Sedng-Kee Park, Takeo Shiba
  • Publication number: 20050244996
    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: July 5, 2005
    Publication date: November 3, 2005
    Inventors: Mutsuko Hatano, Shinya Yamaguchi, Takeo Shiba, Mitsuharu Tai, Hajime Akimoto
  • Patent number: 6949452
    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: Grant
    Filed: June 25, 2003
    Date of Patent: September 27, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Mutsuko Hatano, Shinya Yamaguchi, Takeo Shiba, Mitsuharu Tai, Hajime Akimoto
  • Patent number: 6949419
    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: February 17, 2004
    Date of Patent: September 27, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Takeo Shiba, Mutsuko Hatano, Shinya Yamaguchi, Seong-kee Park
  • Patent number: 6950081
    Abstract: The invention provides an image display device that has an especially satisfactory display quality for animated images, and sufficiently suppresses the irregularities of display quality among pixels. The image display device includes a light emitting drive means that drives a light emitting means, based on an analog display signal inputted to the pixels, and a light emitting control switch for controlling a light-on or light-off of the light emitting means on one end of the light emitting drive means in each pixel.
    Type: Grant
    Filed: August 6, 2002
    Date of Patent: September 27, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Hajime Akimoto, Yoshirou Mikami, Kiyoshige Kinugawa, Shigeyuki Nishitani, Takeo Shiba
  • Publication number: 20050140609
    Abstract: The invention provides an image display device that has an especially satisfactory display quality for animated images, and sufficiently suppresses the irregularities of display quality among pixels. The image display device includes a light emitting drive means that drives a light emitting means, based on an analog display signal inputted to the pixels, and a light emitting control switch for controlling a light-on or light-off of the light emitting means on one end of the light emitting drive means in each pixel.
    Type: Application
    Filed: January 26, 2005
    Publication date: June 30, 2005
    Inventors: Hajime Akimoto, Yoshirou Mikami, Kiyoshige Kinugawa, Shigeyuki Nishitani, Takeo Shiba
  • Publication number: 20050127361
    Abstract: A thin film semiconductor device has a semiconductor thin film with a film thickness of 200 nm or less. The semiconductor thin film is formed over a dielectric substrate with a warping point of 600° C. or lower. The semiconductor thin film has a region in which a first semiconductor thin film region with the defect density of 1×1017 cm?3 or less and a second semiconductor thin film region with the defect density of 1×1017 cm?3 or more are disposed alternately in the form of stripes. The width of the first semiconductor thin film region is larger than the width of the semiconductor thin film region. The grain boundaries, grain size and orientation of crystals over the dielectric substrate are controlled, so that a high quality thin film semiconductor device is obtained.
    Type: Application
    Filed: February 2, 2005
    Publication date: June 16, 2005
    Inventors: Mutsuko Hatano, Shinya Yamaguchi, Takeo Shiba
  • Publication number: 20050121673
    Abstract: This invention provides a manufacturing method for fabricating on the same substrate both high voltage thin film transistors suitable for driving liquid crystal and low voltage drive high performance thin film transistors. In addition, this invention provides a thin film transistor substrate where the area occupied by a storage capacitor in each pixel is reduced to raise the aperture ratio of the display unit. One aspect of this invention provides a manufacturing method characterized in that the impurity regions of both high voltage thin film transistors and high performance thin film transistors which differ in the thickness of gate insulation are formed by implanting a dopant through the same two-layered film. Another aspect of this invention reduces the area occupied by the drive circuit in the display unit by utilizing an extension of one layer of the insulation film included in each thin film transistor.
    Type: Application
    Filed: January 11, 2005
    Publication date: June 9, 2005
    Inventors: Takeshi Satou, Toshihiko Itoga, Takeo Shiba
  • Patent number: 6903368
    Abstract: A thin film made of silicon or another IV-group crystals (crystals and mixed crystals of C, Ge, Sn, and Pb) is twice scanned with a laser beam moving in two lateral directions in which crystal grains grow larger in order to form high-quality polycrystals in exact positions in the thin film, while defects uncontrollable by the prior arts are being reduced significantly, to realize a high-quality TFT device. The laser-scanning directions are defined by the crystallization face orientations.
    Type: Grant
    Filed: July 9, 2002
    Date of Patent: June 7, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Shinya Yamaguchi, Mutsuko Hatano, Takeo Shiba
  • Publication number: 20050101097
    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: December 1, 2004
    Publication date: May 12, 2005
    Inventors: Hiromi Shimamoto, Takashi Uchino, Takeo Shiba, Kazuhiro Ohnishi, Yoichi Tamaki, Takashi Kobayashi, Toshiyuki Kikuchi, Takahide Ikeda
  • Publication number: 20050095822
    Abstract: A method of forming 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: Application
    Filed: December 7, 2004
    Publication date: May 5, 2005
    Inventors: Seong-Kee Park, Shinya Yamaguchi, Mutsuko Hatano, Takeo Shiba
  • Publication number: 20050085021
    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: November 9, 2004
    Publication date: April 21, 2005
    Inventors: Takeo Shiba, Mutsuko Hatano, Shinya Yamaguchi, Seong-kee Park
  • Patent number: 6872977
    Abstract: A thin film semiconductor device has a semiconductor thin film with a film thickness of 200 nm or less. The semiconductor thin film is formed over a dielectric substrate with a warping point of 600° C. or lower. The semiconductor thin film has a region in which a first semiconductor thin film region with the defect density of 1×1017 cm?3 or less and a second semiconductor thin film region with the defect density of 1×1017 cm?3 or more are disposed alternately in the form of stripes. The width of the first semiconductor thin film region is larger than the width of the semiconductor thin film region. The grain boundaries, grain size and orientation of crystals over the dielectric substrate are controlled, so that a high quality thin film semiconductor device is obtained.
    Type: Grant
    Filed: July 5, 2002
    Date of Patent: March 29, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Mutsuko Hatano, Shinya Yamaguchi, Takeo Shiba
  • Publication number: 20050051081
    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 irradiation 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: Application
    Filed: September 17, 2004
    Publication date: March 10, 2005
    Inventors: Kazuo Takeda, Masakazu Saito, Yukio Takasaki, Hironobu Abe, Makoto Ohkura, Yoshinobu Kimura, Takeo Shiba
  • Patent number: 6864134
    Abstract: This invention provides a manufacturing method for fabricating on the same substrate both high voltage thin film transistors suitable for driving liquid crystal and low voltage drive high performance thin film transistors. In addition, this invention provides a thin film transistor substrate where the area occupied by a storage capacitor in each pixel is reduced to raise the aperture ratio of the display unit. One aspect of this invention provides a manufacturing method characterized in that the impurity regions of both high voltage thin film transistors and high performance thin film transistors which differ in the thickness of gate insulation are formed by implanting a dopant through the same two-layered film. Another aspect of this invention reduces the area occupied by the drive circuit in the display unit by utilizing an extension of one layer of the insulation film included in each thin film transistor.
    Type: Grant
    Filed: April 29, 2003
    Date of Patent: March 8, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Takeshi Satou, Toshihiko Itoga, Takeo Shiba