Patents by Inventor Mikio Hongo

Mikio Hongo 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: 7981701
    Abstract: A method of forming a semiconductor thin film includes a highly sensitive inspection method for detecting lateral crystals and a crystallizing method. In the crystallizing method, the time-based pulse width of a laser SXL is modulated and an approximate band-like crystal silicon film SPSI is formed in a desired region while scanning the substrate SUB1 bidirectionally in the X and ?X directions. In the inspection method, an inspection beam PRO1 is irradiated to the substrate just after the laser SXL is turned off. A protrusion TOKI will be formed on the silicon film portion where the laser SXL is turned off if the state of the silicon film is that of a lateral crystal SPSI. The inspection beam PRO1 is scattered by the protrusion TOKI and observed by a detector. If the state of the silicon film is granular crystal GGSI or aggregated film AGSI, such a protrusion TOKI is not observed.
    Type: Grant
    Filed: January 7, 2005
    Date of Patent: July 19, 2011
    Assignee: Hitachi Displays, Ltd.
    Inventors: Mutsuko Hatano, Shinya Yamaguchi, Mikio Hongo, Akio Yazaki, Takeshi Noda
  • Patent number: 7834353
    Abstract: A TFT device having a pixel portion and a driving circuit portion formed on a glass substrate; wherein at least the active layer (active region) of a transistor constituting said driving circuit comprises polycrystalline silicon including crystals that do not have crystal grain boundaries which cross the direction of current flow.
    Type: Grant
    Filed: January 29, 2008
    Date of Patent: November 16, 2010
    Assignee: Hitachi Displays, Ltd.
    Inventors: Mikio Hongo, Sachio Uto, Mineo Nomoto, Toshihiko Nakata, Mutsuko Hatano, Shinya Yamaguchi, Makoto Ohkura
  • Patent number: 7811910
    Abstract: In crystallization of a silicon film by annealing using a linear-shaped laser beam having a width of the short axis of the beam is ununiform, the profile (intensity distribution) of the laser beam is evaluated and the results are fed back to a condition of oscillating the laser beam or an optical condition for projecting the laser beam onto the silicon film, whereby a display device comprising a high-quality crystalline silicon film is manufactured.
    Type: Grant
    Filed: March 6, 2008
    Date of Patent: October 12, 2010
    Assignee: Hitachi Displays, Ltd.
    Inventors: Mikio Hongo, Akio Yazaki, Takahiro Kamo
  • Publication number: 20100167431
    Abstract: A laser processing apparatus which achieves both shorter TAT and reduction in processing defects. In the apparatus, a laser radiation section, an undulation measurement section for measuring undulation of a substrate or a film thickness measuring section for measuring the thickness of a thin film formed on the substrate, and an optical inspection section for optically inspecting grooves formed by laser-processing the thin film on the substrate are fixed so that their positional relationship is kept constant.
    Type: Application
    Filed: October 1, 2009
    Publication date: July 1, 2010
    Inventors: Hironaru YAMAGUCHI, Mikio Hongo, Mitsuyoshi Koizumi, Masaki Araki
  • Patent number: 7732268
    Abstract: A method of manufacturing a display device to improve the quality of a polycrystal silicon upon dehydrogenating and polycrystallizing an amorphous silicon at the outside of a display region of a substrate, by forming a plurality of pixels having TFT devices using an amorphous silicon in the display region of the substrate, and forming a plurality of driving circuits having semiconductor devices using a polycrystal silicon at the outside of the display region, the method including irradiation of a first continuous oscillation laser only to the amorphous silicon in the region for forming the driving circuit and the peripheral region thereof to conduct dehydrogenation and then irradiation of a second continuous oscillation region only to the dehydrogenated region to polycrystallize the amorphous silicon, wherein the region to which the first continuous oscillation laser is irradiated is wider than the region to which the second continuous oscillation laser is irradiated.
    Type: Grant
    Filed: August 6, 2007
    Date of Patent: June 8, 2010
    Assignee: Hitachi Displays, Ltd.
    Inventors: Hideaki Shimmoto, Mikio Hongo, Akio Yazaki, Takeshi Noda, Takuo Kaitoh
  • Patent number: 7723135
    Abstract: In crystallization of a silicon film by annealing with a linear-shaped laser beam having an ununiform width of the short axis of the beam, the profile (intensity distribution) of the laser beam is evaluated, and the result is fed back to an oscillating condition of the laser beam or an optical condition which projects this onto the silicon film, whereby a display device comprising a high-quality crystalline silicon film is produced.
    Type: Grant
    Filed: January 30, 2008
    Date of Patent: May 25, 2010
    Assignee: Hitachi Displays, Ltd.
    Inventors: Akio Yazaki, Mikio Hongo, Takeshi Sato, Takahiro Kamo
  • Patent number: 7456428
    Abstract: A semiconductor thin film is manufactured by scanning laser light or a substrate onto an arbitrary region of the semiconductor thin film and irradiating a laser thereon. The semiconductor thin film is formed by the substantially belt-shaped crystal being crystallized such that crystalline grains grow in the scanning direction, on the substrate, on XY coordinates where value x of beam size W (?m) of the laser light measured in substantially the same direction as the scanning direction is defined as X axis, and where value y of scanning velocity Vs (m/s) is defined as Y axis, the crystallization processing is performed within a region where all of the following conditions hold: condition 1: the beam size W is larger than wavelength of the laser beam, condition 2: the scanning velocity Vs is smaller than upper-limit of crystal growth speed, and condition 3: x×(1/y)<25 ?s.
    Type: Grant
    Filed: February 28, 2007
    Date of Patent: November 25, 2008
    Assignee: Hitachi Displays, Ltd.
    Inventors: Mutsuko Hatano, Mikio Hongo, Akio Yazaki, Mitsuharu Tai, Takeshi Noda, Yukio Takasaki
  • Publication number: 20080227274
    Abstract: In crystallization of a silicon film by annealing using a linear-shaped laser beam having a width of the short axis of the beam is ununiform, the profile (intensity distribution) of the laser beam is evaluated and the results are fed back to a condition of oscillating the laser beam or an optical condition for projecting the laser beam onto the silicon film, whereby a display device comprising a high-quality crystalline silicon film is manufactured.
    Type: Application
    Filed: March 6, 2008
    Publication date: September 18, 2008
    Inventors: Mikio HONGO, Akio Yazaki, Takahiro Kamo
  • Publication number: 20080188012
    Abstract: In crystallization of a silicon film by annealing with a linear-shaped laser beam having an ununiform width of the short axis of the beam, the profile (intensity distribution) of the laser beam is evaluated, and the result is fed back to an oscillating condition of the laser beam or an optical condition which projects this onto the silicon film, whereby a display device comprising a high-quality crystalline silicon film is produced.
    Type: Application
    Filed: January 30, 2008
    Publication date: August 7, 2008
    Inventors: Akio Yazaki, Mikio Hongo, Takeshi Sato, Takahiro Kamo
  • Patent number: 7397831
    Abstract: A laser beam temporally modulated in amplitude by a modulator and shaped into a long and narrow shape by a beam shaper is rotated around the optical axis of an image rotator inserted between the beam shaper and a substrate. Thus, the longitudinal direction of the laser beam having the long and narrow shape is rotated around the optical axis on the substrate. In order to perform annealing in a plurality of directions on the substrate, the laser beam shaped into the long and narrow shape is rotated on the substrate while a stage mounted with the substrate is moved only in two directions, that is, X- and Y-directions. In such a manner, the substrate can be scanned at a high speed with a continuous wave laser beam modulated temporally in amplitude and shaped into a long and narrow shape, without rotating the substrate. Thus, a semiconductor film can be annealed.
    Type: Grant
    Filed: November 15, 2004
    Date of Patent: July 8, 2008
    Assignee: Hitachi Displays, Ltd.
    Inventors: Mikio Hongo, Akio Yazaki, Mutsuko Hatano
  • Publication number: 20080121894
    Abstract: A TFT device having a pixel portion and a driving circuit portion formed on a glass substrate; wherein at least the active layer (active region) of a transistor constituting said driving circuit comprises polycrystalline silicon including crystals that do not have crystal grain boundaries which cross the direction of current flow.
    Type: Application
    Filed: January 29, 2008
    Publication date: May 29, 2008
    Inventors: Mikio HONGO, Sachio Uto, Mineo Nomoto, Toshihiko Nakata, Mutsuko Hatano, Shinya Yamaguchi, Makoto Ohkura
  • Publication number: 20080050893
    Abstract: A method of manufacturing a display device to improve the quality of a polycrystal silicon upon dehydrogenating and polycrystallizing an amorphous silicon at the outside of a display region of a substrate, by forming a plurality of pixels having TFT devices using an amorphous silicon in the display region of the substrate, and forming a plurality of driving circuits having semiconductor devices using a polycrystal silicon at the outside of the display region, the method including irradiation of a first continuous oscillation laser only to the amorphous silicon in the region for forming the driving circuit and the peripheral region thereof to conduct dehydrogenation and then irradiation of a second continuous oscillation region only to the dehydrogenated region to polycrystallize the amorphous silicon, wherein the region to which the first continuous oscillation laser is irradiated is wider than the region to which the second continuous oscillation laser is irradiated.
    Type: Application
    Filed: August 6, 2007
    Publication date: February 28, 2008
    Inventors: Hideaki Shimmoto, Mikio Hongo, Akio Yazaki, Takeshi Noda, Takuo Kaitoh
  • Patent number: 7326623
    Abstract: Arrangements (e.g., methods) for manufacturing a display device, including irradiating an amorphous semiconductor film formed on a substrate with an excimer laser beam to convert the amorphous semiconductor film into a polycrystalline semiconductor film; and irradiating predetermined areas of the polycrystalline semiconductor film intermittently with a continuous wave laser beam while a position of the substrate with respect to the continuous wave laser beam is scanned, crystal grains larger than those of the polycrystalline semiconductor film other than the predetermined areas are formed in each of the predetermined areas locally in the polycrystalline semiconductor film, wherein first thin film transistors are formed in the predetermined areas while second thin film transistors are formed in the polycrystalline semiconductor film other than the predetermined areas thereof.
    Type: Grant
    Filed: August 24, 2005
    Date of Patent: February 5, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Mikio Hongo, Sachio Uto, Mineo Nomoto, Toshihiko Nakata, Mutsuko Hatano, Shinya Yamaguchi, Makoto Ohkura
  • Patent number: 7258586
    Abstract: When any of pixels is not lit in an organic EL display having an organic EL layer between a first electrode and a second electrode, an organic layer of the pixel is observed. If the organic layer of the pixel contains foreign matter, the second electrode is separated into a region in contact with the foreign matter and a region not in contact with both the contact region and the foreign matter. Thus, not-lit display regions are reduced as less as possible, making it possible to manufacture an organic EL display excellent in display performance.
    Type: Grant
    Filed: June 29, 2004
    Date of Patent: August 21, 2007
    Assignee: Hitachi Displays, Ltd.
    Inventors: Takuo Tamura, Mikio Hongo, Masaaki Okunaka, Shinichi Kato, Eiji Matsuzaki, Masato Ito, Masatomo Terakado
  • Patent number: 7253864
    Abstract: A laser beam is selectively directed to an amorphous silicon film of a pixel portion on an active-matrix substrate of a display device to modify the amorphous silicon film into a polysilicon film. Pixel circuits such as thin film transistors are formed on the modified polysilicon film. Thus, it is possible to realize remarkably economically the display device provided with the active-matrix substrate having the high performance thin film transistor circuits.
    Type: Grant
    Filed: October 11, 2005
    Date of Patent: August 7, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Hiroshi Kikuchi, Mikio Hongo, Mutsuko Hatano, Makoto Ohkura
  • Publication number: 20070155140
    Abstract: A semiconductor thin film is manufactured by scanning laser light or a substrate onto an arbitrary region of the semiconductor thin film and irradiating a laser thereon. The semiconductor thin film is formed by the substantially belt-shaped crystal being crystallized such that crystalline grains grow in the scanning direction, on the substrate, on XY coordinates where value x of beam size W (?m) of the laser light measured in substantially the same direction as the scanning direction is defined as X axis, and where value y of scanning velocity Vs (m/s) is defined as Y axis, the crystallization processing is performed within a region where all of the following conditions hold: condition 1: the beam size W is larger than wavelength of the laser beam, condition 2: the scanning velocity Vs is smaller than upper-limit of crystal growth speed, and condition 3: x×(1/y)<25 ?s.
    Type: Application
    Filed: February 28, 2007
    Publication date: July 5, 2007
    Inventors: Mutsuko Hatano, Mikio Hongo, Akio Yazaki, Mitsuharu Tai, Takeshi Noda, Yukio Takasaki
  • Publication number: 20070131962
    Abstract: A display panel includes an insulating substrate, a pixel portion, a gate driver circuit portion, and a drain driver circuit portion. The pixel portion, gate driver circuit portion and drain driver circuit portion are formed out of thin film transistors on the insulating substrate, and the thin film transistors forming the pixel portion, the gate driver circuit portion and the drain driver circuit portion are built in poly-crystalline silicon films, respectively. Each of the poly-crystalline silicon films forming the thin film transistors is formed out of one of at least two kinds of crystal grains different in grain size.
    Type: Application
    Filed: February 15, 2007
    Publication date: June 14, 2007
    Inventors: Akio Yazaki, Mikio Hongo, Mutsuko Hatano, Hiroshi Saito, Makoto Ohkura
  • Patent number: 7202144
    Abstract: A semiconductor thin film is manufactured by scanning laser light or a substrate onto an arbitrary region of the semiconductor thin film and irradiating a laser thereon. The semiconductor thin film is formed by the substantially belt-shaped crystal being crystallized such that crystalline grains grow in the scanning direction, on the substrate, on XY coordinates where value x of beam size W (?m) of the laser light measured in substantially the same direction as the scanning direction is defined as X axis, and where value y of scanning velocity Vs (m/s) is defined as Y axis, the crystallization processing is performed within a region where all of the following conditions hold: condition 1: the beam size W is larger than wavelength of the laser beam, condition 2: the scanning velocity Vs is smaller than upper-limit of crystal growth speed, and condition 3: x×(1/y)<25 ?s.
    Type: Grant
    Filed: December 9, 2004
    Date of Patent: April 10, 2007
    Assignee: Hitachi Displays, Ltd.
    Inventors: Mutsuko Hatano, Mikio Hongo, Akio Yazaki, Mitsuharu Tai, Takeshi Noda, Yukio Takasaki
  • Patent number: 7193693
    Abstract: A mechanism for always measuring the spatial intensity distribution of a laser beam and displacement of the optical axis of the laser beam is provided so that a measured signal is processed when the laser beam incident on a laser beam shaping optical element is out of a predetermined condition. The shape, diameter and incidence position of the laser beam incident on the laser beam shaping optical element are always kept in the predetermined condition by a spatial filter disposed at the position of a focal point of lenses forming a beam expander disposed in the optical axis, on the basis of a result of the signal processing. In this manner, silicon thin films uniform in crystallinity can be formed stably with a high yield on an insulating substrate which forms display panels of flat panel display devices.
    Type: Grant
    Filed: November 19, 2004
    Date of Patent: March 20, 2007
    Assignee: Hitachi Displays, Ltd.
    Inventors: Akio Yazaki, Mikio Hongo, Mutsuko Hatano, Takeshi Noda
  • Patent number: 7183148
    Abstract: An amorphous silicon film on an insulating substrate portion to be formed as an individual display panel in a large-sized insulating substrate is irradiated with a continuous-wave (CW) solid-state laser beam condensed linearly, while being scanned therewith at a fixed speed in the width direction of the condensed laser beam. A pixel portion and a peripheral circuit portion in the same insulating substrate portion are irradiated with the laser beam temporally modulated to have a power density high enough to provide predetermined crystallinity. The amorphous silicon film is transformed into a silicon film having crystallinity corresponding to performance required for thin film transistors to be built in each of the pixel portion and the peripheral circuit portion. In such a manner, a thin film transistor circuit having optimum crystallinity required in the pixel or peripheral circuit portion can be obtained while high throughput is kept.
    Type: Grant
    Filed: August 10, 2004
    Date of Patent: February 27, 2007
    Assignee: Hitachi Displays, Ltd.
    Inventors: Akio Yazaki, Mikio Hongo, Mutsuko Hatano, Hiroshi Saito, Makoto Ohkura