Patents by Inventor Masahiro Hikita

Masahiro Hikita 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).

  • Publication number: 20240112909
    Abstract: A nitride semiconductor epitaxial substrate includes: a Si substrate; a nitride semiconductor epitaxial layer disposed above the Si substrate; and a mixed crystal layer disposed between the Si substrate and the nitride semiconductor epitaxial layer, and containing Si and a group III metal element, the mixed crystal layer containing a high concentration of C. The mixed crystal layer has a concentration of at least 1.0×10+21 cm?3, and a transition metal element concentration of at most 5.0×10+16 cm?3.
    Type: Application
    Filed: January 4, 2022
    Publication date: April 4, 2024
    Inventors: Hisayoshi MATSUO, Hideyuki OKITA, Masahiro HIKITA, Yasuhiro UEMOTO, Manabu YANAGIHARA
  • Publication number: 20230411506
    Abstract: A nitride semiconductor device includes: a substrate; and a first nitride semiconductor layer, a second nitride semiconductor layer, and a third nitride semiconductor layer that are disposed above the substrate in the stated order. The first nitride semiconductor layer includes a recess. The second nitride semiconductor layer has a band gap larger than a band gap of the first nitride semiconductor layer and is disposed in a region other than the recess. The third nitride semiconductor layer has a band gap larger than the band gap of the first nitride semiconductor layer and covers the first nitride semiconductor layer and the second nitride semiconductor layer including an inner wall of the recess. A contact angle at which a side wall of the recess and an interface between the first nitride semiconductor layer and the second nitride semiconductor layer meet ranges from 140° to less than 180°.
    Type: Application
    Filed: October 7, 2021
    Publication date: December 21, 2023
    Inventors: Hideyuki OKITA, Manabu YANAGIHARA, Masahiro HIKITA
  • Publication number: 20230386978
    Abstract: A semiconductor device includes: a substrate; a first nitride semiconductor layer on the substrate; a second nitride semiconductor layer on the first nitride semiconductor layer; finger-shaped source electrodes on the second nitride semiconductor layer; finger-shaped drain electrodes disposed so as to be spaced apart from the source electrodes; and finger-shaped gate electrodes respectively disposed between the source electrodes and the drain electrodes. The gate electrodes are electrically connected, via a first gate integrated wiring, a plurality of second gate integrated wirings and a third gate integrated wiring, to gate pads located on one or both ends of the third gate integrated wiring. A plurality of source pads and the plurality of second gate integrated wirings are formed alternately in a first direction perpendicular to the longitudinal direction of the gate electrodes.
    Type: Application
    Filed: August 25, 2021
    Publication date: November 30, 2023
    Inventors: Masayuki KURODA, Takahiro SATO, Manabu YANAGIHARA, Hideyuki OKITA, Masahiro HIKITA
  • Publication number: 20230361179
    Abstract: A nitride semiconductor device includes: a first active area surrounded by an isolation area; and the following electrodes above the first active area: a source electrode; a first gate electrode and a second gate electrode, one on either side of and spaced from the source electrode in a first direction in plan view; and at least one drain electrode located in a direction opposite the source electrode relative to the first gate electrode or the second gate electrode. The source electrode, the first gate electrode, the second gate electrode, and the at least one drain electrode each include a finger-shaped portion extending in a second direction perpendicular to the first direction in the plan view. A first dielectric film is disposed above the source electrode. The first gate electrode and the second gate electrode are electrically connected by a gate electrode joiner disposed above the first dielectric film.
    Type: Application
    Filed: August 16, 2021
    Publication date: November 9, 2023
    Inventors: Manabu YANAGIHARA, Masayuki KURODA, Hiroto YAMAGIWA, Hideyuki OKITA, Masahiro HIKITA
  • Patent number: 11807044
    Abstract: A motorcycle tire for running on rough terrain includes a tread portion. The tread portion includes a base surface and a plurality of blocks. The blocks include a crown block arranged on a tire equator side and a shoulder block arranged on a tread edge side. A height of the shoulder block from the base surface is larger than a height of the crown block from the base surface. The shoulder block is provided on the base surface side with a base portion that has a locally increased cross-section taken along the base surface.
    Type: Grant
    Filed: February 2, 2021
    Date of Patent: November 7, 2023
    Assignee: SUMITOMO RUBBER INDUSTRIES, LTD.
    Inventor: Masahiro Hikita
  • Publication number: 20230141057
    Abstract: A tread surface 20 of the tire 2 includes a center portion C and a pair of shoulder portions S. A contour line of the tread surface 20 is divided into ten parts. Among the ten parts, two parts including an equator PC are represented by arcs, and two parts including ends PE of the tread surface 20, respectively, are represented by arcs. A bank angle ?b is larger than a camber angle ?c. A ratio of a degree of curvature Bs of the shoulder portion S to a width TW of the tread surface 20 is not less than 50%. A ratio of a camber height d to a tire cross-sectional height H is not less than 50%.
    Type: Application
    Filed: November 9, 2022
    Publication date: May 11, 2023
    Applicant: SUMITOMO RUBBER INDUSTRIES, LTD.
    Inventors: Masahiro HIKITA, Neill RAMPTON
  • Publication number: 20230143715
    Abstract: A tread surface 20 of the tire 2 includes a center portion C and a pair of shoulder portions S. A contour line of the tread surface 20 is divided into ten parts. Among the ten parts, two parts including an equator PC are represented by arcs, and two parts including ends PE of the tread surface 20, respectively, are represented by arcs. A degree of curvature of each shoulder portion S is higher than a degree of curvature of the center portion C. A ratio of the degree of curvature of the shoulder portion S to a width TW of the tread surface 20 is not less than 50%. A ratio of the degree of curvature of the center portion C to the width TW of the tread surface 20 is not greater than 70%.
    Type: Application
    Filed: November 9, 2022
    Publication date: May 11, 2023
    Applicant: Sumitomo Rubber Industries, Ltd.
    Inventors: Masahiro HIKITA, Neill RAMPTON
  • Patent number: 11560018
    Abstract: To improve uneven wear resistance performance while maintaining drainage performance. A tyre is provided with a plurality of inclined grooves in a tread portion. Each of the inclined grooves includes a first portion arranged on a crown region side, a second portion arranged on a shoulder region side, and a third portion connecting between the first portion and the second portion. In a ground contacting surface of the tread portion, the third portion has a groove width smaller than the first portion and the second portion. The third portion includes an outer portion arranged on the ground contacting surface side and an inner portion arranged radially inside the outer portion. The inner portion has a groove width larger than the outer portion.
    Type: Grant
    Filed: February 18, 2020
    Date of Patent: January 24, 2023
    Assignee: SUMITOMO RUBBER INDUSTRIES, LTD.
    Inventor: Masahiro Hikita
  • Patent number: 11554612
    Abstract: To improve uneven wear resistance performance while maintaining drainage performance. A tyre is provided with a plurality of inclined grooves in a tread portion. Each of the inclined grooves extends from a crown region to a shoulder region. Each of the inclined grooves includes a first portion arranged on the crown region side, a second portion arranged on the shoulder region side, and a third portion connecting between the first portion and the second portion. The third portion has a groove width smaller than the first portion and the second portion. The first portion, the second portion, and the third portion are inclined to the same side with respect to the tyre circumferential direction.
    Type: Grant
    Filed: February 18, 2020
    Date of Patent: January 17, 2023
    Assignee: SUMITOMO RUBBER INDUSTRIES, LTD.
    Inventor: Masahiro Hikita
  • Publication number: 20220392887
    Abstract: The semiconductor device includes: a semiconductor substrate; a first transistor disposed above the semiconductor substrate and including a first source electrode, a first gate region, and a first drain electrode; and a second transistor disposed above the semiconductor substrate and including a second source electrode, a second gate region, and a second drain electrode. The first source electrode, the second gate region, and the second source electrode are substantially at an identical potential. The first drain electrode and the second drain electrode are substantially at an identical potential.
    Type: Application
    Filed: October 29, 2020
    Publication date: December 8, 2022
    Inventors: Manabu YANAGIHARA, Takahiro SATO, Hiroto YAMAGIWA, Masahiro HIKITA
  • Publication number: 20220320091
    Abstract: An integrated semiconductor device includes an Si substrate, and a high-side transistor and a low-side transistor which configure a half-bridge. A source electrode of a unit transistor configuring the high-side transistor and a drain electrode of a unit transistor configuring the low-side transistor are integrated as a common electrode.
    Type: Application
    Filed: August 21, 2020
    Publication date: October 6, 2022
    Inventors: Manabu YANAGIHARA, Takahiro SATO, Hiroto YAMAGIWA, Masahiro HIKITA
  • Patent number: 11458773
    Abstract: A tyre for running on rough terrain includes a tread portion. The tread portion includes a crown region, middle regions, and shoulder regions. The crown region is provided with a plurality of crown blocks. The middle regions are provided with a plurality of middle blocks. The shoulder regions are provided with a plurality of shoulder blocks. Each of the middle blocks is connected with at least one of the crown blocks by a crown tie bar and connected with at least one of the shoulder blocks by a shoulder tie bar. A land ratio of the shoulder regions is 90% or more and 115% or less of a land ratio of the crown region.
    Type: Grant
    Filed: July 26, 2019
    Date of Patent: October 4, 2022
    Assignee: SUMITOMO RUBBER INDUSTRIES, LTD.
    Inventor: Masahiro Hikita
  • Publication number: 20220302259
    Abstract: A semiconductor device includes: a substrate; a first nitride semiconductor layer above the substrate; a second nitride semiconductor layer above the first nitride semiconductor layer and being greater than the first nitride semiconductor layer in band gap; and a first field-effect transistor including a first source electrode, a first drain electrode, and a first gate electrode that are above the second nitride semiconductor layer, the first source electrode and the first drain electrode being separated from each other, the first gate electrode being disposed between the first source electrode and the first drain electrode. The first field-effect transistor includes a third semiconductor layer that is above the second nitride semiconductor layer in part of a region between lower part of the first source electrode and the first gate electrode, and is separated from the first gate electrode. The third semiconductor layer and the first source electrode are electrically connected.
    Type: Application
    Filed: August 21, 2020
    Publication date: September 22, 2022
    Inventors: Hiroto YAMAGIWA, Manabu YANAGIHARA, Takahiro SATO, Masahiro HIKITA, Hiroaki UENO, Yusuke KINOSHITA
  • Publication number: 20220254902
    Abstract: A nitride semiconductor device includes a semiconductor layered structure including a substrate, a channel layer, and a barrier layer. The channel layer is formed above the substrate and made of a nitride semiconductor layer. The barrier layer is formed on the channel layer, has a wider band gap than the channel layer, and is made of a nitride semiconductor layer. The semiconductor layered structure includes an isolation region in which impurities are implanted. The position of an impurity concentration peak in the depth direction in the isolation region is deeper than the interface between the barrier layer and the channel layer. The concentration of the impurities at the interface between the barrier layer and the channel layer in the isolation region is lower than the concentration at the impurity concentration peak.
    Type: Application
    Filed: June 24, 2020
    Publication date: August 11, 2022
    Inventors: Hideyuki OKITA, Masahiro HIKITA, Manabu YANAGIHARA
  • Publication number: 20220190152
    Abstract: A semiconductor device includes: a substrate; a channel layer constituted of a single nitride semiconductor on the substrate; a first barrier layer which is a nitride semiconductor on a part of an upper surface of the channel layer and having a band gap larger than that of the channel layer; a gate layer which is a nitride semiconductor on and in contact with the first barrier layer; a second barrier layer which is a nitride semiconductor in contact with the first barrier layer in an area where the gate layer is not disposed above the channel layer, and having a band gap larger than that of the channel layer and having a thickness or a band gap independent from the first barrier layer; a gate electrode on the gate layer; and a source electrode and a drain electrode spaced apart from the gate layer and on the second barrier layer.
    Type: Application
    Filed: March 7, 2022
    Publication date: June 16, 2022
    Inventors: Hideyuki OKITA, Masahiro HIKITA, Yasuhiro UEMOTO
  • Patent number: 11198332
    Abstract: A tyre includes a tread portion provided with blocks each protruding toward a ground contact surface thereof from a tread bottom surface, and axially spaced side portions each extending from the tread portion to a respective bead portion. The blocks include shoulder blocks spaced. The shoulder blocks each include an overhanging portion located axially outside the corresponding side portion. The overhanging portion includes a pair of first walls extending in substantially parallel with a tyre meridian cross-section. The shoulder blocks have shoulder block lengths which are lengths in the tyre circumferential direction measured between the pair of first walls along the ground contact surface, wherein the shoulder block lengths are shorter than gap lengths which are lengths in the tyre circumferential direction measured on the tread bottom surface between adjacent shoulder blocks.
    Type: Grant
    Filed: November 29, 2018
    Date of Patent: December 14, 2021
    Assignee: SUMITOMO RUBBER INDUSTRIES, LTD.
    Inventor: Masahiro Hikita
  • Patent number: 11171228
    Abstract: A nitride semiconductor device includes: a substrate; a first nitride semiconductor layer disposed above the substrate; a second nitride semiconductor layer disposed above the first nitride semiconductor layer and having a band gap larger than a band gap of the first nitride semiconductor layer; a third nitride semiconductor layer selectively disposed above the second nitride semiconductor layer and containing a p-type first impurity element; a high resistance region disposed in the third nitride semiconductor layer, the high resistance region containing a second impurity element and having a specific resistance higher than a specific resistance of the third nitride semiconductor layer; and a gate electrode disposed above the high resistance region, wherein an end of the high resistance region is inside a surface end of the third nitride semiconductor layer.
    Type: Grant
    Filed: December 9, 2019
    Date of Patent: November 9, 2021
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Hideyuki Okita, Manabu Yanagihara, Masahiro Hikita
  • Patent number: 11152499
    Abstract: A nitride semiconductor device includes: a substrate; a first nitride semiconductor layer; a second nitride semiconductor layer having a greater band gap than the first nitride semiconductor layer; a source electrode and a drain electrode on the second nitride semiconductor layer apart from each other; a third nitride semiconductor layer, between the source electrode and the drain electrode, containing a p-type first impurity and serving as a gate; and a fourth nitride semiconductor layer, between the third nitride semiconductor layer and the drain electrode, containing a p-type second impurity, wherein the average carrier concentration of the fourth nitride semiconductor layer is lower than the average carrier concentration of the third nitride semiconductor layer.
    Type: Grant
    Filed: September 18, 2019
    Date of Patent: October 19, 2021
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Hideyuki Okita, Manabu Yanagihara, Takahiro Sato, Masahiro Hikita
  • Publication number: 20210300124
    Abstract: A motorcycle tire for running on rough terrain includes a tread portion. The tread portion includes a base surface and a plurality of blocks. The blocks include a crown block arranged on a tire equator side and a shoulder block arranged on a tread edge side. A height of the shoulder block from the base surface is larger than a height of the crown block from the base surface. The shoulder block is provided on the base surface side with a base portion that has a locally increased cross-section taken along the base surface.
    Type: Application
    Filed: February 2, 2021
    Publication date: September 30, 2021
    Applicant: Sumitomo Rubber Industries, Ltd.
    Inventor: Masahiro HIKITA
  • Patent number: 11104185
    Abstract: The disclosure provides a method of manufacturing a motorcycle tire for uneven terrain travel in which both a rigid feeling at the time of driving and a shock absorbing ability are able to be achieved. Provided is a method of manufacturing a motorcycle tire for uneven terrain travel including a process of molding a green tire including a tread portion, a pair of sidewall portions and a pair of bead portions, and a vulcanization process of vulcanizing the green tire using a mold. In the mold, a clip width, which is a distance in a tire axial direction between a pair of bead molding surfaces which form outer surfaces of the pair of bead portions, is 100% to 110% of a rim width of a normal rim to which a completed motorcycle tire is attached.
    Type: Grant
    Filed: May 17, 2018
    Date of Patent: August 31, 2021
    Assignee: SUMITOMO RUBBER INDUSTRIES, LTD.
    Inventors: Masahiro Hikita, Shizuya Aoki