Patents by Inventor Mitsuru Nakata

Mitsuru Nakata 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: 7724382
    Abstract: A laser irradiation process includes: scanning a substrate with laser having a predetermined lasing frequency at different irradiation intensities to form a plurality of first irradiation areas corresponding to the irradiation intensities; illuminating the first irradiation areas to reflected light receive from the fist irradiation areas; determining microcrystallization intensity based on the received reflected light; and determining irradiation intensity based on the thus determined microcrystallization intensity. The laser irradiation process uses the irradiation intensity for irradiating a polycrystalline film in a product semiconductor device.
    Type: Grant
    Filed: April 19, 2007
    Date of Patent: May 25, 2010
    Assignees: NEC Corporation, NEC LCD Technologies, Ltd.
    Inventors: Mitsuru Nakata, Hirofumi Shimamoto, Hiroshi Kanoh
  • Publication number: 20100123132
    Abstract: To form an oxide semiconductor TFT having a fine property, which can be utilized for driving elements of a display, on a cheap glass substrate or a resin substrate such as PET that is light and flexible with fine regenerability and yield. Through radiating pulse light to an oxide semiconductor, a fine-quality oxide semiconductor film can be formed on a glass substrate or a resin substrate such as PET. This makes it possible to manufacture thin film devices having a fine property with fine regenerability and yield.
    Type: Application
    Filed: November 18, 2009
    Publication date: May 20, 2010
    Inventors: Mitsuru Nakata, Kazushige Takechi
  • Patent number: 7714327
    Abstract: An electronic device of the present invention includes a first substrate provided with a thin film active element, having a thickness of 200 ?m or lower, and a second substrate formed with a high thermal conductivity portion. The second substrate is applied to one surface of the two surfaces of the first substrate, i.e., the surface being the side other than the side that formed with the thin film active element. The thin film active element has a maximum power consumption of 0.01 to 1 mW. The high thermal conductivity portion is a region that corresponds to the position of the thin film active element and whose thermal conductivity falls within the range from 0.1 to 4 W/cm·deg.
    Type: Grant
    Filed: August 23, 2006
    Date of Patent: May 11, 2010
    Assignee: NEC Corporation
    Inventors: Kazushige Takechi, Hiroshi Kanou, Mitsuru Nakata
  • Publication number: 20100019175
    Abstract: A manufacturing method of a semiconductor thin film decreases the number of and controls the direction of crystal grain boundaries. A first beam irradiated onto amorphous silicon produces a radial temperature gradient centered on a tip of a concave. This forms a crystal grain in the concave tip, which grows in both the beam width and length direction. After the second beam and on, growth is repeated using the crystal grain formed in the tip of the concave as the seed. This forms a band-form crystal grain with a wider than that of the conventional narrow-line beam, with the tip of the concave being the start point. Further, by setting the periphery of the concave pattern to be equal or less than the crystal grain diameter in the direction vertical to the beam scanning direction, it is possible to form the band-form crystal grain being lined continuously.
    Type: Application
    Filed: September 17, 2009
    Publication date: January 28, 2010
    Applicant: NEC CORPORATION
    Inventor: Mitsuru NAKATA
  • Patent number: 7611577
    Abstract: A manufacturing method of a semiconductor thin film decreases the number of and controls the direction of crystal grain boundaries. A first beam irradiated onto amorphous silicon produces a radial temperature gradient centered on a tip of a concave. This forms a crystal grain in the concave tip, which grows in both the beam width and length direction. After the second beam and on, growth is repeated using the crystal grain formed in the tip of the concave as the seed. This forms a band-form crystal grain with a wider than that of the conventional narrow-line beam, with the tip of the concave being the start point. Further, by setting the periphery of the concave pattern to be equal or less than the crystal grain diameter in the direction vertical to the beam scanning direction, it is possible to form the band-form crystal grain being lined continuously.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: November 3, 2009
    Assignee: NEC Corporation
    Inventor: Mitsuru Nakata
  • Patent number: 7579222
    Abstract: Method of manufacturing a thin film device substrate wherein no trench fabrication is required to be applied onto the substrate surface, and a material which is impervious to light can be used, and the substrate can be peeled off quickly. Firstly, a peeling-off film, a silicon oxide film and an amorphous silicon film are formed in succession on a glass substrate, and the amorphous silicon film is irradiated from above to obtain a polycrystalline silicon film. Subsequently, using the polycrystalline silicon film as an active layer, a TFT is formed, and then a plastic substrate is bonded thereon, and finally the glass substrate is peeled off with the peeling-off film, to complete transfer of the TFT. Because the peeling-off film has a gap space, its etching rate is high. Therefore, it is unnecessary to form a trench for supplying an etchant on the surface of the glass substrate.
    Type: Grant
    Filed: August 14, 2006
    Date of Patent: August 25, 2009
    Assignee: NEC Corporation
    Inventors: Mitsuru Nakata, Kazushige Takechi, Hiroshi Kanoh
  • Publication number: 20080237724
    Abstract: To provide a semiconductor thin film on which crystal grains with large diameters are formed over a wide range. A beam pattern including a plurality of recessed patterns is scan-irradiated to amorphous silicon in a first scanning direction (first crystallization step). Then, a beam pattern is scan-irradiated in a second scanning direction that is different from the first scanning direction by 90 degrees (second crystallization step). As a result, by having band-shape crystal grains formed in the first crystallization step as seeds, the crystal grain diameters thereof are expanded in the second scanning direction. That is, it is possible to obtain new band-shape crystal grains with the expanded grain diameters.
    Type: Application
    Filed: March 19, 2008
    Publication date: October 2, 2008
    Applicant: NEC LCD Technologies, Ltd.
    Inventor: Mitsuru NAKATA
  • Publication number: 20080135785
    Abstract: A method of manufacturing a semiconductor thin film includes (A) forming an amorphous semiconductor film on a substrate, (B) irradiating a beam to a surface of the amorphous semiconductor film such that a predetermined region of the amorphous semiconductor film is melted and solidified to form a crystallized semiconductor film, and (C) scanning the beam in a first direction. A second direction is a direction on the surface of the amorphous semiconductor film perpendicular to the first direction. A length along the second direction of a cross section of the beam is substantially equal to or less than two times a width along the second direction of the crystallized semiconductor film.
    Type: Application
    Filed: January 7, 2008
    Publication date: June 12, 2008
    Inventors: Hiromichi Takaoka, Mitsuru Nakata
  • Patent number: 7354810
    Abstract: A method of manufacturing a semiconductor thin film includes (A) forming an amorphous semiconductor film on a substrate, (B) irradiating a beam to a surface of the amorphous semiconductor film such that a predetermined region of the amorphous semiconductor film is melted and solidified to form a crystallized semiconductor film, and (C) scanning the beam in a first direction. A second direction is a direction on the surface of the amorphous semiconductor film perpendicular to the first direction. A length along the second direction of a cross section of the beam is substantially equal to or less than two times a width along the second direction of the crystallized semiconductor film.
    Type: Grant
    Filed: May 28, 2004
    Date of Patent: April 8, 2008
    Assignee: NEC Corporation
    Inventors: Hiromichi Takaoka, Mitsuru Nakata
  • Publication number: 20080038882
    Abstract: A thin-film device includes a first electrical insulator, an oxide-semiconductor film formed on the first electrical insulator, and a second electrical insulator formed on the oxide-semiconductor film, the oxide-semiconductor film defining an active layer. The oxide-semiconductor film is comprised of a first interface layer located at an interface with the first electrical insulating insulator, a second interface layer located at an interface with the second electrical insulator, and a bulk layer other than the first and second interface layers. A density of oxygen holes in at least one of the first and second interlayer layers is smaller than a density of oxygen holes in the bulk layer.
    Type: Application
    Filed: August 6, 2007
    Publication date: February 14, 2008
    Inventors: Kazushige Takechi, Mitsuru Nakata
  • Publication number: 20080035920
    Abstract: A thin-film transistor array includes an electrically insulating substrate, a plurality of thin-film transistors arranged in a matrix on the substrate, and each including a channel, a source, and a drain each comprised of an oxide-semiconductor film, a pixel electrode integrally formed with the drain, a source signal line through which a source signal is transmitted to a group of thin-film transistors, a gate signal line through which a gate signal is transmitted to a group of thin-film transistors, a source terminal formed at an end of the source signal line, and a gate terminal formed at an end of the gate signal line. The source terminal and the gate terminal are formed in the same layer as a layer in which the channel is formed. The source terminal and the gate terminal have the same electric conductivity as that of the pixel electrode.
    Type: Application
    Filed: August 7, 2007
    Publication date: February 14, 2008
    Applicants: NEC Corporation, NEC LCD Technologies, Ltd.
    Inventors: Kazushige Takechi, Mitsuru Nakata
  • Publication number: 20070248774
    Abstract: A printing medium includes: a rectangular lens sheet that has a surface formed in a predetermined lens shape; and a thin base that is fixed to a rear surface of the lens sheet on which no lens is formed and has an extending portion extending from one side of the lens sheet to the outside. In the printing medium, when a region corresponding to the rear surface of the lens sheet is referred to as a unit region, the extending portion includes a plurality of unit regions adjacent to one another with adjacent portions, which are common sides, interposed therebetween, and a first printing surface and a second printing surface having predetermined images formed thereon are formed in corresponding unit regions on one surface of the base that is fixed to the rear surface of the lens sheet or the other surface of the base. In addition, at least one unit region is additionally interposed between the unit region where the first printing surface is formed and the unit region where the second printing surface is formed.
    Type: Application
    Filed: April 24, 2007
    Publication date: October 25, 2007
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Katsuhito SUZUKI, Mitsuaki YOSHIZAWA, Mitsuru NAKATA, Fumiaki MUKAIYAMA
  • Publication number: 20070249134
    Abstract: A laser irradiation process includes: scanning a substrate with laser having a predetermined lasing frequency at different irradiation intensities to form a plurality of first irradiation areas corresponding to the irradiation intensities; illuminating the first irradiation areas to reflected light receive from the fist irradiation areas; determining microcrystallization intensity based on the received reflected light; and determining irradiation intensity based on the thus determined microcrystallization intensity. The laser irradiation process uses the irradiation intensity for irradiating a polycrystalline film in a product semiconductor device.
    Type: Application
    Filed: April 19, 2007
    Publication date: October 25, 2007
    Applicants: NEC CORPORATION, NEC LCD Technologies, Ltd.
    Inventors: MITSURU NAKATA, Hirofumi Shimamoto, Hiroshi Kanoh
  • Patent number: 7256102
    Abstract: An object of the present invention is to prevent the thin film device formed by laser annealing from making, due to overheat, abnormal operations. Firstly, on a glass substrate 101. a heat insulating film, a silicon oxide film and an amorphous silicon film are formed in succession, and the amorphous silicon film is irradiated from above with a laser beam of an excimer laser. After being molten, the amorphous silicon film undergoes recrystallization to form a polycrystalline silicon film. Subsequently, using the polycrystalline silicon film as an active layer, a TFT is formed, and then a plastic substrate is bonded onto the TFT, and finally the glass substrate is peeled off by way of the heat insulating film, whereby a transfer of the TFT is completed. Because the heat insulating film is removed, abnormality caused by overheat at the time of operation is well prevented from occurring.
    Type: Grant
    Filed: November 1, 2004
    Date of Patent: August 14, 2007
    Assignee: NEC Corporation
    Inventors: Mitsuru Nakata, Kazushige Takechi, Hiroshi Kanoh
  • Publication number: 20070049061
    Abstract: An electronic device of the present invention includes a first substrate provided with a thin film active element, having a thickness of 200 ?m or lower, and a second substrate formed with a high thermal conductivity portion. The second substrate is applied to one surface of the two surfaces of the first substrate, i.e., the surface being the side other than the side that formed with the thin film active element. The thin film active element has a maximum power consumption of 0.01 to 1 mW. The high thermal conductivity portion is a region that corresponds to the position of the thin film active element and whose thermal conductivity falls within the range from 0.1 to 4 W/cm·deg.
    Type: Application
    Filed: August 23, 2006
    Publication date: March 1, 2007
    Applicant: NEC Corporation
    Inventors: Kazushige Takechi, Hiroshi Kanou, Mitsuru Nakata
  • Publication number: 20060276007
    Abstract: Method of manufacturing a thin film device substrate wherein no trench fabrication is required to be applied onto the substrate surface, and a material which is impervious to light can be used, and the substrate can be peeled off quickly. Firstly, a peeling-off film, a silicon oxide film and an amorphous silicon film are formed in succession on a glass substrate, and the amorphous silicon film is irradiated from above to obtain a polycrystalline silicon film. Subsequently, using the polycrystalline silicon film as an active layer, a TFT is formed, and then a plastic substrate is bonded thereon, and finally the glass substrate is peeled off with the peeling-off film, to complete transfer of the TFT. Because the peeling-off film has a gap space, its etching rate is high. Therefore, it is unnecessary to form a trench for supplying an etchant on the surface of the glass substrate.
    Type: Application
    Filed: August 14, 2006
    Publication date: December 7, 2006
    Applicant: NEC CORPORATION
    Inventors: Mitsuru Nakata, Kazushige Takechi, Hiroshi Kanoh
  • Publication number: 20050221569
    Abstract: A manufacturing method of a semiconductor thin film decreases the number of and controls the direction of crystal grain boundaries. A first beam irradiated onto amorphous silicon produces a radial temperature gradient centered on a tip of a concave. This forms a crystal grain in the concave tip, which grows in both the beam width and length direction. After the second beam and on, growth is repeated using the crystal grain formed in the tip of the concave as the seed. This forms a band-form crystal grain with a wider than that of the conventional narrow-line beam, with the tip of the concave being the start point. Further, by setting the periphery of the concave pattern to be equal or less than the crystal grain diameter in the direction vertical to the beam scanning direction, it is possible to form the band-form crystal grain being lined continuously.
    Type: Application
    Filed: March 31, 2005
    Publication date: October 6, 2005
    Applicant: NEC CORPORATION
    Inventor: Mitsuru Nakata
  • Publication number: 20050095755
    Abstract: An object of the present invention is to prevent the thin film device formed by laser annealing from making, due to overheat, abnormal operations. Firstly, on a glass substrate 101. a heat insulating film, a silicon oxide film and an amorphous silicon film are formed in succession, and the amorphous silicon film is irradiated from above with a laser beam of an excimer laser. After being molten, the amorphous silicon film undergoes recrystallization to form a polycrystalline silicon film. Subsequently, using the polycrystalline silicon film as an active layer, a TFT is formed, and then a plastic substrate is bonded onto the TFT, and finally the glass substrate is peeled off by way of the heat insulating film, whereby a transfer of the TFT is completed. Because the heat insulating film is removed, abnormality caused by overheat at the time of operation is well prevented from occurring.
    Type: Application
    Filed: November 1, 2004
    Publication date: May 5, 2005
    Applicant: NEC CORPORATON
    Inventors: Mitsuru Nakata, Kazushige Takechi, Hiroshi Kanoh
  • Publication number: 20050003591
    Abstract: A method of manufacturing a semiconductor thin film includes (A) forming an amorphous semiconductor film on a substrate, (B) irradiating a beam to a surface of the amorphous semiconductor film such that a predetermined region of the amorphous semiconductor film is melted and solidified to form a crystallized semiconductor film, and (C) scanning the beam in a first direction. A second direction is a direction on the surface of the amorphous semiconductor film perpendicular to the first direction. A length along the second direction of a cross section of the beam is substantially equal to or less than two times a width along the second direction of the crystallized semiconductor film.
    Type: Application
    Filed: May 28, 2004
    Publication date: January 6, 2005
    Inventors: Hiromichi Takaoka, Mitsuru Nakata