Patents by Inventor Atsushi Kurokawa

Atsushi Kurokawa 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: 20200161226
    Abstract: A dielectric film is disposed on a semiconductor substrate, and a conductor including a bent section is arranged between the semiconductor substrate and the dielectric film. A pad is disposed on the dielectric film. The pad is covered with a protective film. The protective film has an opening through which an upper surface of the pad is exposed. The bent section in the conductor and the pad overlap each other as seen in plan view, and an inside corner and an outside corner in the bent section are chamfered.
    Type: Application
    Filed: January 22, 2020
    Publication date: May 21, 2020
    Applicant: Murata Manufacturing Co., Ltd.
    Inventors: Atsushi KUROKAWA, Hiroaki TOKUYA, Kazuya KOBAYASHI, Yuichi SANO
  • Publication number: 20200161265
    Abstract: A first wiring is disposed above operating regions of plural unit transistors formed on a substrate. A second wiring is disposed above the substrate. An insulating film is disposed on the first and second wirings. First and second cavities are formed in the insulating film. As viewed from above, the first and second cavities entirely overlap with the first and second wirings, respectively. A first bump is disposed on the insulating film and is electrically connected to the first wiring via the first cavity. A second bump is disposed on the insulating film and is electrically connected to the second wiring via the second cavity. As viewed from above, at least one of the plural operating regions is disposed within the first bump and is at least partially disposed outside the first cavity. The planar configuration of the first cavity and that of the second cavity are substantially identical.
    Type: Application
    Filed: January 24, 2020
    Publication date: May 21, 2020
    Inventors: Atsushi KUROKAWA, Masayuki AOIKE, Takayuki TSUTSUI
  • Publication number: 20200152545
    Abstract: A semiconductor chip is mounted on a substrate in a face-down manner. A metal film is arranged on a back surface of the semiconductor chip facing an opposite side from the substrate away from an edge of the back surface. A sealing resin layer seals the semiconductor chip with a part of the metal film being exposed from the sealing resin layer.
    Type: Application
    Filed: January 16, 2020
    Publication date: May 14, 2020
    Applicant: Murata Manufacturing Co., Ltd.
    Inventors: Atsushi KUROKAWA, Yuichi SANO, Toshihiro TADA
  • Patent number: 10636897
    Abstract: In a bipolar transistor, a collector layer includes three semiconductor layers: an n-type GaAs layer (Si concentration: about 5×1015 cm?3, thickness: about 350 nm), a p-type GaAs layer (C concentration: about 4.5×1015 cm?3, thickness: about 100 nm, sheet concentration: 4.5×1010 cm?2), and an n-type GaAs layer Si concentration: about 5×1015 cm?3, thickness: about 500 nm. The sheet concentration of the p-type GaAs layer is set to less than 1×1011 cm?2.
    Type: Grant
    Filed: October 25, 2018
    Date of Patent: April 28, 2020
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yasunari Umemoto, Atsushi Kurokawa, Tsunekazu Saimei
  • Publication number: 20200119171
    Abstract: A bipolar transistor has a subcollector layer and a stack of collector, base, and emitter layers on the subcollector layer. On the subcollector layer are collector electrodes. On the base layer are base electrodes. The collector layer includes multiple doped layers with graded impurity concentrations, higher on the subcollector layer side and lower on the base layer side. Of these doped layers, the one having the highest impurity concentration is in contact with the subcollector layer and has a sheet resistance less than or equal to about nine times that of the subcollector layer.
    Type: Application
    Filed: December 11, 2019
    Publication date: April 16, 2020
    Applicant: Murata Manufacturing Co., Ltd.
    Inventors: Yasunari UMEMOTO, Shigeki KOYA, Atsushi KUROKAWA
  • Patent number: 10580748
    Abstract: A first wiring is disposed above operating regions of plural unit transistors formed on a substrate. A second wiring is disposed above the substrate. An insulating film is disposed on the first and second wirings. First and second cavities are formed in the insulating film. As viewed from above, the first and second cavities entirely overlap with the first and second wirings, respectively. A first bump is disposed on the insulating film and is electrically connected to the first wiring via the first cavity. A second bump is disposed on the insulating film and is electrically connected to the second wiring via the second cavity. As viewed from above, at least one of the plural operating regions is disposed within the first bump and is at least partially disposed outside the first cavity. The planar configuration of the first cavity and that of the second cavity are substantially identical.
    Type: Grant
    Filed: December 5, 2018
    Date of Patent: March 3, 2020
    Assignee: MURATA MANUFACTURING CO., LTD.
    Inventors: Atsushi Kurokawa, Masayuki Aoike, Takayuki Tsutsui
  • Patent number: 10566303
    Abstract: A transistor includes a semiconductor region provided on a substrate and three different terminal electrodes. At least one terminal electrode has an isolated electrode structure composed of a plurality of conductor patterns. A bump, which electrically connects the plurality of conductor patterns to each other, is arranged on the terminal electrode having the isolated electrode structure. A stress-relaxing layer, which is composed of a metal material containing a high-melting-point metal, is arranged between the semiconductor region of the transistor and the bump. No current path for connecting the plurality of conductor patterns to each other is arranged between the conductor patterns and the bump.
    Type: Grant
    Filed: December 4, 2018
    Date of Patent: February 18, 2020
    Assignee: MURATA MANUFACTURING CO., LTD.
    Inventor: Atsushi Kurokawa
  • Patent number: 10559547
    Abstract: A semiconductor chip includes a semiconductor substrate having a main surface, first and second electrodes, a first insulating layer, and first and second bumps. The first and second electrodes are formed above the main surface of the semiconductor substrate. The first insulating layer is formed above a first portion of the first electrode. The first bump is formed above a second portion of the first electrode and above the first insulating layer and is electrically connected to the first electrode. The second bump is formed above the second electrode. The area of the second bump is larger than that of the first bump in a plan view of the main surface of the semiconductor substrate. The first insulating layer adjusts the distance from the main surface of the semiconductor substrate to the top surface of the first bump in a direction normal to the main surface.
    Type: Grant
    Filed: June 12, 2018
    Date of Patent: February 11, 2020
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Masahiro Shibata, Daisuke Tokuda, Atsushi Kurokawa, Hiroaki Tokuya, Yasunari Umemoto
  • Patent number: 10541320
    Abstract: A bipolar transistor has a subcollector layer and a stack of collector, base, and emitter layers on the subcollector layer. On the subcollector layer are collector electrodes. On the base layer are base electrodes. The collector layer includes multiple doped layers with graded impurity concentrations, higher on the subcollector layer side and lower on the base layer side. Of these doped layers, the one having the highest impurity concentration is in contact with the subcollector layer and has a sheet resistance less than or equal to about nine times that of the subcollector layer.
    Type: Grant
    Filed: April 4, 2019
    Date of Patent: January 21, 2020
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yasunari Umemoto, Shigeki Koya, Atsushi Kurokawa
  • Publication number: 20200006265
    Abstract: A target element to be protected and a protrusion are arranged on a substrate. An insulating film arranged on the substrate covers the target element and at least a side surface of the protrusion. An electrode pad for external connection is arranged on the insulating film. The electrode pad at least partially overlaps the target element and the protrusion as seen in plan view. A maximum distance between the upper surface of the protrusion and the electrode pad in the height direction is shorter than a maximum distance between the upper surface of the target element and the electrode pad in the height direction.
    Type: Application
    Filed: June 26, 2019
    Publication date: January 2, 2020
    Inventors: Kazuya KOBAYASHI, Atsushi KUROKAWA, Hiroaki TOKUYA, Isao OBU, Yuichi SAITO
  • Publication number: 20190363042
    Abstract: A semiconductor device includes a semiconductor chip mounted to a mounting substrate with an interposer interposed therebetween such that a surface of the semiconductor chip on which bumps are formed faces a surface of the mounting substrate. The mounting substrate has a plurality of metal parts formed as terminals on a surface of the mounting substrate and in contact with electrode pads connected to multilayer wiring. The semiconductor chip has a plurality of functional elements formed in an inner layer and a plurality of bumps formed in contact with element wiring lines of the functional elements such that the bumps protrude from the surface of the semiconductor chip. The interposer has a plurality of first recesses formed in the surface of the interposer facing the surface of the semiconductor chip on which the bumps are formed such that the first recesses accommodate only the bumps.
    Type: Application
    Filed: May 14, 2019
    Publication date: November 28, 2019
    Inventors: Yuichi SANO, Atsushi KUROKAWA
  • Publication number: 20190267479
    Abstract: A semiconductor device includes a semiconductor element including a bipolar transistor disposed on a compound semiconductor substrate, a collector electrode, a base electrode, and an emitter electrode, the bipolar transistor including a collector layer, a base layer, and an emitter layer, the collector electrode being in contact with the collector layer, the base electrode being in contact with the base layer, the emitter electrode being in contact with the emitter layer; a protective layer disposed on one surface of the semiconductor element; an emitter redistribution layer electrically connected to the emitter electrode via a contact hole in the protective layer; and a stress-relieving layer disposed between the emitter redistribution layer and the emitter layer in a direction perpendicular to a surface of the compound semiconductor substrate.
    Type: Application
    Filed: February 6, 2019
    Publication date: August 29, 2019
    Inventors: Atsushi KUROKAWA, Yuichi SANO
  • Publication number: 20190237566
    Abstract: A bipolar transistor has a subcollector layer and a stack of collector, base, and emitter layers on the subcollector layer. On the subcollector layer are collector electrodes. On the base layer are base electrodes. The collector layer includes multiple doped layers with graded impurity concentrations, higher on the subcollector layer side and lower on the base layer side. Of these doped layers, the one having the highest impurity concentration is in contact with the subcollector layer and has a sheet resistance less than or equal to about nine times that of the subcollector layer.
    Type: Application
    Filed: April 4, 2019
    Publication date: August 1, 2019
    Applicant: Murata Manufacturing Co., Ltd.
    Inventors: Yasunari UMEMOTO, Shigeki KOYA, Atsushi KUROKAWA
  • Publication number: 20190172773
    Abstract: A wiring is disposed above operating regions of plural unit transistors arranged on a substrate in a first direction. An insulating film is disposed on the wiring. A cavity entirely overlapping with the wiring as viewed from above is formed in the insulating film. A metal member electrically connected to the wiring via the cavity is disposed on the insulating film. The centroid of the cavity is displaced from that of the operating region of the corresponding unit transistor in the first direction. When the cavity having a centroid the closest to the operating region of a unit transistor is defined as the closest proximity cavity, the amount of deviation of the centroid of the closest proximity cavity from that of the operating region of the corresponding unit transistor in the first direction becomes greater from the center to the ends of the arrangement direction of the unit transistors.
    Type: Application
    Filed: December 5, 2018
    Publication date: June 6, 2019
    Inventors: Atsushi KUROKAWA, Masayuki AOIKE, Takayuki TSUTSUI
  • Publication number: 20190172807
    Abstract: A first wiring is disposed above operating regions of plural unit transistors formed on a substrate. A second wiring is disposed above the substrate. An insulating film is disposed on the first and second wirings. First and second cavities are formed in the insulating film. As viewed from above, the first and second cavities entirely overlap with the first and second wirings, respectively. A first bump is disposed on the insulating film and is electrically connected to the first wiring via the first cavity. A second bump is disposed on the insulating film and is electrically connected to the second wiring via the second cavity. As viewed from above, at least one of the plural operating regions is disposed within the first bump and is at least partially disposed outside the first cavity. The planar configuration of the first cavity and that of the second cavity are substantially identical.
    Type: Application
    Filed: December 5, 2018
    Publication date: June 6, 2019
    Inventors: Atsushi KUROKAWA, Masayuki AOIKE, Takayuki TSUTSUI
  • Publication number: 20190172806
    Abstract: A transistor includes a semiconductor region provided on a substrate and three different terminal electrodes. At least one terminal electrode has an isolated electrode structure composed of a plurality of conductor patterns. A bump, which electrically connects the plurality of conductor patterns to each other, is arranged on the terminal electrode having the isolated electrode structure. A stress-relaxing layer, which is composed of a metal material containing a high-melting-point metal, is arranged between the semiconductor region of the transistor and the bump. No current path for connecting the plurality of conductor patterns to each other is arranged between the conductor patterns and the bump.
    Type: Application
    Filed: December 4, 2018
    Publication date: June 6, 2019
    Inventor: Atsushi KUROKAWA
  • Patent number: 10297680
    Abstract: A bipolar transistor has a subcollector layer and a stack of collector, base, and emitter layers on the subcollector layer. On the subcollector layer are collector electrodes. On the base layer are base electrodes. The collector layer includes multiple doped layers with graded impurity concentrations, higher on the subcollector layer side and lower on the base layer side. Of these doped layers, the one having the highest impurity concentration is in contact with the subcollector layer and has a sheet resistance less than or equal to about nine times that of the subcollector layer.
    Type: Grant
    Filed: April 19, 2018
    Date of Patent: May 21, 2019
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yasunari Umemoto, Shigeki Koya, Atsushi Kurokawa
  • Publication number: 20190067460
    Abstract: In a bipolar transistor, a collector layer includes three semiconductor layers: an n-type GaAs layer (Si concentration: about 5×1015 cm?3, thickness: about 350 nm), a p-type GaAs layer (C concentration: about 4.5×1015 cm?3, thickness: about 100 nm, sheet concentration: 4.5×1010 cm?2), and an n-type GaAs layer Si concentration: about 5×1015 cm?3, thickness: about 500 nm. The sheet concentration of the p-type GaAs layer is set to less than 1×1011 cm?2.
    Type: Application
    Filed: October 25, 2018
    Publication date: February 28, 2019
    Applicant: Murata Manufacturing Co., Ltd.
    Inventors: Yasunari UMEMOTO, Atsushi KUROKAWA, Tsunekazu SAIMEI
  • Patent number: 10209645
    Abstract: A developing device includes a casing to contain developer, a developer bearer, an upper and lower developer conveyors to convey the developer to one side in an axial direction of rotation shafts thereof, a communicating portion disposed on a first end side on which an input gear is disposed, to fall the developer from the upper developer conveyor to the lower developer conveyor, bearings to receive end portions the upper and lower developer conveyors, and first and second end seals to seal gaps in the bearings on the upper and lower developer conveyors, respectively. The first end seals and the second end are disposed on the first end side and a second end side, respectively. A sliding friction between the rotation shaft and at least one of the first end seals is smaller than a sliding friction between the rotation shaft and the second end seal.
    Type: Grant
    Filed: September 6, 2017
    Date of Patent: February 19, 2019
    Assignee: RICOH COMPANY, LTD.
    Inventors: Yuuki Tsuchiya, Masayuki Yamane, Keiichi Yoshida, Atsushi Kurokawa, Toshiki Hayashi, Tatsuya Ohhira
  • Publication number: 20190006306
    Abstract: A semiconductor chip includes a semiconductor substrate having a main surface, first and second electrodes, a first insulating layer, and first and second bumps. The first and second electrodes are formed above the main surface of the semiconductor substrate. The first insulating layer is formed above a first portion of the first electrode. The first bump is formed above a second portion of the first electrode and above the first insulating layer and is electrically connected to the first electrode. The second bump is formed above the second electrode. The area of the second bump is larger than that of the first bump in a plan view of the main surface of the semiconductor substrate. The first insulating layer adjusts the distance from the main surface of the semiconductor substrate to the top surface of the first bump in a direction normal to the main surface.
    Type: Application
    Filed: June 12, 2018
    Publication date: January 3, 2019
    Applicant: Murata Manufacturing Co., Ltd.
    Inventors: Masahiro SHIBATA, Daisuke TOKUDA, Atsushi KUROKAWA, Hiroaki TOKUYA, Yasunari UMEMOTO