Patents by Inventor Michinobu Mizumura

Michinobu Mizumura 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: 10896817
    Abstract: A laser irradiation apparatus includes a light source that generates a laser beam, a projection lens that radiates the laser beam onto a predetermined region of an amorphous silicon thin film deposited on each of a plurality of thin film transistors on a glass substrate, and a projection mask pattern provided on the projection lens and has a plurality of openings so that the laser beam is radiated onto each of the plurality of thin film transistors, wherein the projection lens radiates the laser beam onto the plurality of thin film transistors on the glass substrate, which moves in a predetermined direction, through the projection mask pattern, and the projection mask pattern is provided such that the openings are not continuous in one column orthogonal to the moving direction.
    Type: Grant
    Filed: May 13, 2019
    Date of Patent: January 19, 2021
    Assignees: V Technology Co. Ltd., Sakai Display Products Corporation
    Inventors: Michinobu Mizumura, Nobutake Nodera, Yoshiaki Matsushima, Masakazu Tanaka, Takao Matsumoto
  • Patent number: 10896978
    Abstract: In an oxide semiconductor device including an active layer region constituted by an oxide semiconductor, stability when a stress is applied is improved. The oxide semiconductor device includes an active layer region constituted by an oxide semiconductor of indium (In), gallium (Ga), and zinc (Zn), wherein the active layer region contains an element selected from titanium (Ti), zirconium (Zr), and hafnium (Hf) that are Group 4 elements, or carbon (C), silicon (Si), germanium (Ge), and tin (Sn) that are Group 14 elements at a number density in a range of 1×1016 to 1×1020 cm?3.
    Type: Grant
    Filed: September 4, 2017
    Date of Patent: January 19, 2021
    Assignees: V TECHNOLOGY CO., LTD., TOHOKU UNIVERSITY
    Inventors: Tetsuya Goto, Michinobu Mizumura
  • Publication number: 20200388495
    Abstract: A laser irradiation device includes a light source that generates laser light; a projection lens that radiates the laser light to a predetermined region of an amorphous silicon thin film deposited on a thin film transistor; and a projection mask including a plurality of opening portions disposed on the projection lens and through which the laser light passes, wherein a predetermined pattern that is able to reduce diffraction of the laser light is formed at a peripheral edge portion of each of the plurality of opening portions.
    Type: Application
    Filed: December 26, 2018
    Publication date: December 10, 2020
    Inventor: Michinobu Mizumura
  • Patent number: 10840095
    Abstract: A laser irradiation device includes a light source that generates a laser beam, a projection lens that irradiates a predetermined region of an amorphous silicon thin film, mounted on each of a plurality of thin-film transistors on a glass substrate moving in a predetermined direction, with the laser beam, and a projection mask pattern provided on the projection lens and has a plurality of columns each including a predetermined number of opening portions and provided parallel to the predetermined direction, in which the projection lens emits the laser beam through the projection mask pattern, and the projection mask pattern is configured such that at least some of the predetermined number of opening portions are not on a straight line parallel to the predetermined direction in each of the plurality of columns.
    Type: Grant
    Filed: June 25, 2019
    Date of Patent: November 17, 2020
    Assignee: V Technology Co., Ltd.
    Inventor: Michinobu Mizumura
  • Patent number: 10818492
    Abstract: The present invention provides a method for manufacturing a thin film transistor including processing of irradiating an amorphous silicon film 8 deposited on a substrate with laser light. The method comprises: a laser annealing step for forming a polysilicon film 9 including a channel region 52 by irradiating an area including a formation region of the region 52 in the film 8 with the laser light such that the area including the formation region is heated, melted, and recrystallized; and a removing step for etching off an area outside the region 52 from the polysilicon film 9. Thus, the present invention can provide a method for manufacturing a thin film transistor and a mask for use in the manufacturing method that are capable of promoting the recrystallization of the film 8 and thereby improving its electron mobility even when laser irradiation has to be performed under restricted irradiation conditions.
    Type: Grant
    Filed: August 28, 2018
    Date of Patent: October 27, 2020
    Assignee: V TECHNOLOGY CO., LTD.
    Inventor: Michinobu Mizumura
  • Publication number: 20200266062
    Abstract: A laser irradiation device includes a light source that generates laser light; and a laser head including cylindrical lenses that receive the laser light and generate a thin line laser beam parallel to a moving direction of a substrate, wherein the laser head irradiates a predetermined region of the substrate covered with an amorphous silicon thin film with the thin line laser beam and forms a polysilicon thin film in the predetermined region.
    Type: Application
    Filed: May 8, 2020
    Publication date: August 20, 2020
    Inventor: Michinobu Mizumura
  • Publication number: 20200194260
    Abstract: A laser irradiation device includes a light source that generates laser light, a projection lens that radiates the laser light to a predetermined region of an amorphous silicon thin film deposited on a substrate, and a projection mask pattern provided on the projection lens and having a plurality of opening portions so that a predetermined region of the amorphous silicon thin film is irradiated with the laser light, wherein each of the plurality of opening portions has a transmittance based on a projection magnification of the projection lens.
    Type: Application
    Filed: February 25, 2020
    Publication date: June 18, 2020
    Inventor: Michinobu Mizumura
  • Publication number: 20200176284
    Abstract: A laser irradiation device is provided with a light source that generates a laser beam, a projection lens that irradiates a prescribed region of an amorphous silicon thin film deposited on a substrate with the laser beam, and a projection mask pattern that is disposed on the projection lens and provided with a plurality of opening portions such that the prescribed region of the amorphous silicon thin film is irradiated with the laser beam; wherein the projection lens irradiates the prescribed region of the amorphous silicon thin film on the substrate moving in a prescribed direction with the laser beam through the projection mask pattern and the areas of at least neighboring opening portions in the projection mask pattern differ from each other in one row orthogonal to the movement direction.
    Type: Application
    Filed: February 11, 2020
    Publication date: June 4, 2020
    Inventors: Michinobu Mizumura, Makoto Hatanaka, Toshinari Arai
  • Publication number: 20200171601
    Abstract: A laser irradiation device includes a light source for generating a laser beam, a projection lens for irradiating a prescribed region of an amorphous silicon thin film deposited on a substrate with the laser beam, and a projection mask pattern that is disposed on the projection lens and that includes a rectangular transmission region for transmitting the laser beam in a prescribed projection pattern; and is characterized in that a short side of the rectangular transmission region has a length that causes the irradiation energy of the laser beam passing through the projection mask pattern to become substantially uniform in the prescribed region.
    Type: Application
    Filed: February 5, 2020
    Publication date: June 4, 2020
    Inventors: Michinobu Mizumura, Makoto Hatanaka, Toshinari Arai
  • Publication number: 20200171602
    Abstract: A laser annealing device includes a light source that generates laser light; a fly-eye lens that makes an intensity distribution of the laser light uniform; a projection mask that masks the laser light having passed through the fly-eye lens; and a projection lens that forms a laser beam that irradiates a predetermined range of a substrate with the laser light having passed through the projection mask, wherein an arrangement orientation of the fly-eye lens is rotated by a predetermined angle with respect to an arrangement of a mask pattern of the projection mask to reduce moire that may be generated by interference fringes generated when the laser light passes through the projection mask passing through the fly-eye lens.
    Type: Application
    Filed: February 11, 2020
    Publication date: June 4, 2020
    Inventor: Michinobu Mizumura
  • Publication number: 20200168642
    Abstract: A laser irradiation device is provided with a light source that generates laser light, and a projection lens for applying the laser light to predetermined regions of an amorphous silicon thin film deposited on a substrate. The laser irradiation device also arranged such that the projection lens includes a first projection lens for applying the laser light to first regions corresponding to a channel region of a thin film transistor, the first regions being a part of the predetermined regions, and a second projection lens for applying the laser light to second regions corresponding to predetermined elements included in a gate driver, the second regions being a part of the predetermined regions.
    Type: Application
    Filed: February 3, 2020
    Publication date: May 28, 2020
    Inventor: Michinobu Mizumura
  • Patent number: 10651294
    Abstract: The present invention provides a laser annealing method for irradiating laser light L to an amorphous silicon thin film deposited on a substrate to obtain polysilicon, the method including: multiply irradiating the laser light L while changing an irradiation area of the laser light L on the amorphous silicon thin film to achieve such a grain size distribution that a crystal grain size of the polysilicon decreases from a central portion to a side edge portion at least along a center line C of the irradiation area of the laser light L. The above laser annealing method can reduce a leak current through a simple process.
    Type: Grant
    Filed: April 17, 2019
    Date of Patent: May 12, 2020
    Assignee: V TECHNOLOGY CO., LTD.
    Inventor: Michinobu Mizumura
  • Publication number: 20200144303
    Abstract: Cracking or chipping in a substrate can be prevented while improving durability of a TFT with respect to external force caused by bending, winding, and the like. In a flexible substrate, a recessed portion is formed in a second surface opposite to a first surface in which a thin film transistor is formed, and the recessed portion is disposed at a position not overlapping with the thin film transistor as viewed in a first direction substantially orthogonal to the first surface.
    Type: Application
    Filed: January 6, 2020
    Publication date: May 7, 2020
    Inventors: Koichi KAJIYAMA, Michinobu MIZUMURA
  • Patent number: 10644133
    Abstract: The present invention provides a laser annealing method for irradiating laser light L to an amorphous silicon thin film deposited on a substrate to obtain polysilicon, the method including: multiply irradiating the laser light L while changing an irradiation area of the laser light L on the amorphous silicon thin film to achieve such a grain size distribution that a crystal grain size of the polysilicon decreases from a central portion to a side edge portion at least along a center line C of the irradiation area of the laser light L. The above laser annealing method can reduce a leak current through a simple process.
    Type: Grant
    Filed: April 17, 2019
    Date of Patent: May 5, 2020
    Assignee: V TECHNOLOGY CO., LTD.
    Inventor: Michinobu Mizumura
  • Patent number: 10626491
    Abstract: The present invention provides a method for manufacturing a deposition mask, which irradiates laser light L to a resin film 20 to form an opening pattern 4 having a polygonal shape in a plan view, the method including a step of irradiating the laser light L that is shaped using a beam-shaping mask 10 having a light transmissive window 18 that allows the laser light L to pass therethrough with light transmittance gradually reducing with distance from an edge of the light transmissive window 18 on at least one of opposing sides thereof within an area outside the light transmissive window 18 to thereby form the opening pattern 4 having at least one pair of opposing side walls 4a that are inclined to open wide toward a surface of the film 20 to be irradiated with the laser light L, from a surface opposite to the irradiated surface.
    Type: Grant
    Filed: November 16, 2018
    Date of Patent: April 21, 2020
    Assignee: V TECHNOLOGY CO., LTD.
    Inventor: Michinobu Mizumura
  • Patent number: 10622484
    Abstract: The present invention provides a thin film transistor including a gate electrode, a source electrode, a drain electrode, and a semiconductor layer, which are laminated on a substrate. The semiconductor layer is a polysilicon thin film. The polysilicon thin film in regions corresponding to the source electrode and the drain electrode has a smaller crystal grain size than that of the polysilicon thin film in a channel region between the source electrode and the drain electrode.
    Type: Grant
    Filed: November 7, 2018
    Date of Patent: April 14, 2020
    Assignee: V TECHNOLOGY CO., LTD.
    Inventors: Michinobu Mizumura, Makoto Hatanaka, Tetsuya Kiguchi
  • Patent number: 10608115
    Abstract: A laser beam irradiation device includes a light source that emits a laser beam; and a projection lens that irradiates a plurality of different areas of an amorphous silicon thin film attached to a thin-film transistor with the laser beam, wherein the projection lens irradiates the plurality of different areas of the amorphous silicon thin film with the laser beam such that a source electrode and a drain electrode of the thin-film transistor are connected in parallel to each other by a plurality of channel regions.
    Type: Grant
    Filed: January 18, 2019
    Date of Patent: March 31, 2020
    Assignee: V Technology Co., Ltd.
    Inventor: Michinobu Mizumura
  • Publication number: 20200066518
    Abstract: A laser annealing method is for irradiating an amorphous silicon film formed on a substrate 6 with laser beams and crystallizing the amorphous silicon film, wherein a plurality of first and second TFT formation portions 23, 24 on the substrate 6 are irradiated with laser beams at differing irradiation doses so as to crystallize the amorphous silicon film in the first TFT formation portions 23 into a polysilicon film having a crystalline state and crystallize the amorphous silicon film in the second TFT formation portions 24 into a polysilicon film having another crystalline state that is different from that of the polysilicon film in the first TFT formation portions 23.
    Type: Application
    Filed: November 1, 2019
    Publication date: February 27, 2020
    Inventor: Michinobu MIZUMURA
  • Publication number: 20200066517
    Abstract: A laser annealing method is for irradiating an amorphous silicon film formed on a substrate 6 with laser beams and crystalizing the amorphous silicon film, wherein a plurality of first and second TFT formation portions 23, 24 on the substrate 6 are irradiated with laser beams at differing irradiation doses so as to crystalize the amorphous silicon film in the first TFT formation portions 23 into a polysilicon film having a crystalline state and crystalize the amorphous silicon film in the second TFT formation portions 24 into a polysilicon film having another crystalline state that is different from that of the polysilicon film in the first TFT formation portions 23.
    Type: Application
    Filed: November 1, 2019
    Publication date: February 27, 2020
    Inventor: Michinobu MIZUMURA
  • Publication number: 20200020530
    Abstract: A laser irradiation device includes a light source that generates laser light; a projection lens that emits the laser light onto a predetermined area of an amorphous silicon thin film deposited on a thin film transistor; and a projection mask pattern that is disposed in the projection lens and transmits the laser light in a predetermined projection pattern, wherein the projection mask pattern includes auxiliary patterns disposed in the surroundings of a transmission area corresponding to the predetermined area in addition to the transmission area and transmits the laser light.
    Type: Application
    Filed: February 20, 2018
    Publication date: January 16, 2020
    Inventor: Michinobu Mizumura