Patents by Inventor Yasuhiro Okamoto

Yasuhiro Okamoto 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: 10117567
    Abstract: An endoscope includes a bending section being disposed in an insertion section, a plurality of towing members disposed in the insertion section and in an operation section from the bending section, a disk member turnably provided in the operation section and configured to turn to tow and loosen the plurality of towing members, the plurality of towing members being suspended in an outer circumference of the disk member, operation members turnably disposed in the operation section and configured to turn the disk member to bend the bending section, and a turning shaft configured to turnably axially support the disk member and the operation members with respect to the operation section in a position decentered to the distal end side by a predetermined distance d with respect to a center of the disk member in an initial state in which the bending section is linear.
    Type: Grant
    Filed: August 31, 2016
    Date of Patent: November 6, 2018
    Assignee: OLYMPUS CORPORATION
    Inventor: Yasuhiro Okamoto
  • Patent number: 10105038
    Abstract: An insertion apparatus includes: a flexible tube; an electric driving source arranged on a proximal end side of the flexible tube; a driven portion arranged on a distal end of the flexible tube; and a single driving force transmitting member inserted in the flexible tube and formed by being wound in a coil shape. For the driving force transmitting member, first torsional rigidity in a first rotating state of being rotated in a direction of being wound in the coil shape is set higher than second torsional rigidity in a second rotating state of being rotated in an opposite direction; and the driven portion performs a first motion by the first rotating state and performs a second motion requiring a larger amount of force than the first motion by the second rotating state.
    Type: Grant
    Filed: April 5, 2017
    Date of Patent: October 23, 2018
    Assignee: OLYMPUS CORPORATION
    Inventor: Yasuhiro Okamoto
  • Publication number: 20180235440
    Abstract: An endoscope includes a flexible tube section including coiled tubes, a motor disposed on a proximal side of the flexible tube section, a driving force transmission unit disposed on a distal side of the flexible tube section, and a drive shaft provided inside the flexible tube section along a long axis, the drive shaft being caused to perform rotation around the long axis by a driving force of the motor and to transmit the rotation of the motor to the driving force transmission unit, where torsional resistance of the flexible tube section around the long axis is set higher than torsional resistance between a relay gear of the motor and a drive gear of the driving force transmission unit through the drive shaft.
    Type: Application
    Filed: April 23, 2018
    Publication date: August 23, 2018
    Applicant: OLYMPUS CORPORATION
    Inventor: Yasuhiro OKAMOTO
  • Publication number: 20180233590
    Abstract: In a group III nitride-type field effect transistor, the present invention reduces a leak current component by conduction of residual carriers in a buffer layer, and achieves improvement in a break-down voltage, and enhances a carrier confinement effect (carrier confinement) of a channel to improve pinch-off characteristics (to suppress a short channel effect). For example, when applying the present invention to a GaN-type field effect transistor, besides GaN of a channel layer, a composition-modulated (composition-gradient) AlGaN layer in which aluminum composition reduces toward a top gradually or stepwise is used as a buffer layer (hetero buffer).
    Type: Application
    Filed: March 16, 2018
    Publication date: August 16, 2018
    Inventors: Takashi Inoue, Tatsuo Nakayama, Yuji Ando, Yasuhiro Murase, Kazuki Ota, Hironobu Miyamoto, Katsumi Yamanoguchi, Naotaka Kuroda, Akio Wakejima, Yasuhiro Okamoto
  • Patent number: 10050142
    Abstract: The characteristics of a semiconductor device are improved. A semiconductor device has a potential fixed layer containing a p type impurity, a channel layer, and a barrier layer, formed over a substrate, and a gate electrode arranged in a trench penetrating through the barrier layer, and reaching some point of the channel layer via a gate insulation film. Source and drain electrodes are formed on opposite sides of the gate electrode. The p type impurity-containing potential fixed layer has an inactivated region containing an inactivating element such as hydrogen between the gate and drain electrodes. Thus, while raising the p type impurity (acceptor) concentration of the potential fixed layer on the source electrode side, the p type impurity of the potential fixed layer is inactivated on the drain electrode side. This can improve the drain-side breakdown voltage while providing a removing effect of electric charges by the p type impurity.
    Type: Grant
    Filed: October 20, 2017
    Date of Patent: August 14, 2018
    Assignee: Renesas Electronics Corporation
    Inventors: Tatsuo Nakayama, Hironobu Miyamoto, Ichiro Masumoto, Yasuhiro Okamoto, Shinichi Miyake, Hiroshi Kawaguchi
  • Publication number: 20180219089
    Abstract: A mesa portion of a semiconductor device, which includes a channel base layer formed of a first nitride semiconductor layer, a channel layer formed of a second nitride semiconductor layer, a barrier layer formed of a third nitride semiconductor layer, a mesa-type fourth nitride semiconductor layer, a gate insulating film that covers the mesa portion, and a gate electrode formed over the gate insulating film, is used as a co-doped layer. The mesa portion is used as the co-doped layer, so that interface charges generated at an interface between the gate insulating film and the mesa portion can be cancelled by p-type impurity or n-type impurity in the co-doped layer and a threshold potential can be improved. Further, the fourth nitride semiconductor layer is n-type until the gate insulating film is formed, and the fourth nitride semiconductor layer is made neutral or p-type after the gate insulating film is formed.
    Type: Application
    Filed: December 14, 2017
    Publication date: August 2, 2018
    Applicant: Renesas Electronics Corporation
    Inventors: Tatsuo NAKAYAMA, Hironobu MIYAMOTO, Yasuhiro OKAMOTO
  • Patent number: 10014403
    Abstract: A semiconductor device includes a first nitride semiconductor layer formed over a substrate, a second nitride semiconductor layer formed over the first nitride semiconductor layer, a third nitride semiconductor layer formed over the second nitride semiconductor layer, a fourth nitride semiconductor layer formed over the third nitride semiconductor layer, a trench that penetrates the fourth nitride semiconductor layer and reaches as far as the third nitride semiconductor layer, a gate electrode disposed by way of a gate insulation film in the trench, a first electrode and a second electrode formed respectively over the fourth nitride semiconductor layer on both sides of the gate electrode, and a coupling portion for coupling the first electrode and the first nitride semiconductor layer.
    Type: Grant
    Filed: February 21, 2017
    Date of Patent: July 3, 2018
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Tatsuo Nakayama, Hironobu Miyamoto, Yasuhiro Okamoto, Yoshinao Miura, Takashi Inoue
  • Publication number: 20180151377
    Abstract: A semiconductor device includes a first nitride semiconductor layer formed over a substrate, a second nitride semiconductor layer formed over the first nitride semiconductor layer and having a band gap wider than a band gap of the first nitride semiconductor layer, a trench penetrating through the second nitride semiconductor layer and reaching an inside of the first nitride semiconductor layer, a gate electrode placed in the trench over a gate insulating film, and a first electrode and a second electrode formed over the second nitride semiconductor layer on both sides of the gate electrode, respectively.
    Type: Application
    Filed: January 29, 2018
    Publication date: May 31, 2018
    Inventors: Takashi Inoue, Tatsuo Nakayama, Yasuhiro Okamoto, Hiroshi Kawaguchi, Toshiyuki Takewaki, Nobuhiro Nagura, Takayuki Nagai, Yoshinao Miura, Hironobu Miyamoto
  • Patent number: 9984884
    Abstract: A method of manufacturing a semiconductor device includes forming a first nitride semiconductor layer, forming thereover a second nitride semiconductor layer having a band gap wider than that of the first nitride semiconductor layer, and thereby forming a stacked body, etching the stacked body with a first film placed over the stacked body and including a first opening portion as a mask to form a trench penetrating through the second nitride semiconductor layer and reaching an inside of the first nitride semiconductor layer, causing an end portion of the first film to retreat from an end portion of the trench, forming a second film over the first film including the inside of the trench, and forming a gate electrode over the second film.
    Type: Grant
    Filed: December 20, 2016
    Date of Patent: May 29, 2018
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Takashi Inoue, Tatsuo Nakayama, Yasuhiro Okamoto, Hiroshi Kawaguchi, Toshiyuki Takewaki, Nobuhiro Nagura, Takayuki Nagai, Yoshinao Miura, Hironobu Miyamoto
  • Patent number: 9985108
    Abstract: An electrode comes in ohmic contact with an AlGaN layer. A semiconductor device SD has a nitride semiconductor layer GN2, and an AlxGa(1-x)N layer AGN (hereinafter referred to as “AlGaN layer AGN), and Al electrodes DE, SE. in the AlGaN layer AGN, 0<x?0.2 is satisfied. Also, both of a concentration of a p-type impurity and a concentration of an n-type impurity in the AlGaN layer AGN are 1×1016 cm?3 or lower. In this example, the p-type impurity is exemplified by, for example, Be, C, and Mg, and the n-type impurity is exemplified by Si, S, and Se. Also, the Al electrodes DE and SE are connected to the AlGaN layer AGN. Because a composition ratio of Al is limited to the above-mentioned range, the Al electrodes DE and SE are brought into ohmic contact with the AlGaN layer AGN.
    Type: Grant
    Filed: July 14, 2014
    Date of Patent: May 29, 2018
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Tatsuo Nakayama, Masaaki Kanazawa, Yasuhiro Okamoto, Takashi Inoue, Hironobu Miyamoto, Ryohei Nega
  • Patent number: 9954087
    Abstract: In a group III nitride-type field effect transistor, the present invention reduces a leak current component by conduction of residual carriers in a buffer layer, and achieves improvement in a break-down voltage, and enhances a carrier confinement effect (carrier confinement) of a channel to improve pinch-off characteristics (to suppress a short channel effect). For example, when applying the present invention to a GaN-type field effect transistor, besides GaN of a channel layer, a composition-modulated (composition-gradient) AlGaN layer in which aluminum composition reduces toward a top gradually or stepwise is used as a buffer layer (hetero buffer).
    Type: Grant
    Filed: August 27, 2014
    Date of Patent: April 24, 2018
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Takashi Inoue, Tatsuo Nakayama, Yuji Ando, Yasuhiro Murase, Kazuki Ota, Hironobu Miyamoto, Katsumi Yamanoguchi, Naotaka Kuroda, Akio Wakejima, Yasuhiro Okamoto
  • Patent number: 9936860
    Abstract: A bending apparatus includes: a bending portion; an operation element erected vertically from an operation portion having a longitudinal axis and has a shaft portion in which a tilt direction and tilt angle are changeable; a pulling member having one end connected to the bending portion; a pulley on which a rotary body around which the pulling member is wound is arranged; a motor that generates a driving force that rotates the pulley to pull the pulling member wound around the rotary body in a winding direction; a hanging frame that extends in a diameter direction of the shaft portion, and includes an attachment portion to which the other end of the pulling member is attached; and an attachment path setting member provided inside the operation portion, which changes a path of the pulling to the longitudinal axis direction and guides the pulling member to the attachment portion.
    Type: Grant
    Filed: February 25, 2015
    Date of Patent: April 10, 2018
    Assignee: OLYMPUS CORPORATION
    Inventors: Yasuhiro Okamoto, Hiroki Moriyama
  • Publication number: 20180061983
    Abstract: The characteristics of a semiconductor device are improved. A semiconductor device has a potential fixed layer containing a p type impurity, a channel layer, and a barrier layer, formed over a substrate, and a gate electrode arranged in a trench penetrating through the barrier layer, and reaching some point of the channel layer via a gate insulation film. Source and drain electrodes are formed on opposite sides of the gate electrode. The p type impurity-containing potential fixed layer has an inactivated region containing an inactivating element such as hydrogen between the gate and drain electrodes. Thus, while raising the p type impurity (acceptor) concentration of the potential fixed layer on the source electrode side, the p type impurity of the potential fixed layer is inactivated on the drain electrode side. This can improve the drain-side breakdown voltage while providing a removing effect of electric charges by the p type impurity.
    Type: Application
    Filed: October 20, 2017
    Publication date: March 1, 2018
    Applicant: Renesas Electronics Corporation
    Inventors: Tatsuo NAKAYAMA, Hironobu MIYAMOTO, Ichiro MASUMOTO, Yasuhiro OKAMOTO, Shinichi MIYAKE, Hiroshi KAWAGUCHI
  • Patent number: 9895052
    Abstract: An insertion instrument includes an insertion portion having a curving portion, and an operation portion body coupled to the proximal side of the insertion portion. The operation portion body includes a first surface, and a second surface extending from the first surface and extending in a direction different from the direction in which the first surface extends. A finger side other than a thumb of a grasping hand is located in the second surface. The operation portion body includes a first curving operation portion which is provided in the first surface and which curves the curving portion in a first direction, a functional switch which is provided in the second surface and which operates a predetermined function of the insertion instrument, and a second curving operation portion which is provided in the second surface.
    Type: Grant
    Filed: March 4, 2016
    Date of Patent: February 20, 2018
    Assignee: OLYMPUS CORPORATION
    Inventor: Yasuhiro Okamoto
  • Publication number: 20180042455
    Abstract: An attachment unit includes a tube main body attached to an insertion section of an endoscope and disposed to be rotatable around a longitudinal axis of the insertion section and a fin section protrudingly provided on an outer circumferential surface of the tube main body and spirally extended along a longitudinal axis of the tube main body. In the fin section, a first force amount necessary for bringing down the fin section toward an insertion section distal end side direction and a second force amount necessary for bringing down the fin section toward an insertion section proximal end side direction, which is an opposite direction of the insertion section distal end side direction, are different. In the fin section provided on the tube main body, the first force amount is smaller than the second force amount.
    Type: Application
    Filed: October 23, 2017
    Publication date: February 15, 2018
    Applicant: OLYMPUS CORPORATION
    Inventor: Yasuhiro OKAMOTO
  • Publication number: 20180042456
    Abstract: An attachment unit includes a tube main body attached to an insertion section of an endoscope and disposed to be rotatable around a longitudinal axis of the insertion section and a fin section protrudingly provided on an outer circumferential surface of the tube main body and spirally extended along a longitudinal axis of the tube main body. In the fin section, a first force amount necessary for bringing down the fin section toward a distal end side direction and a second force amount necessary for bringing down the fin section toward a proximal end side direction, which is an opposite direction of the distal end side, are different. In the fin section provided on the tube main body, the first force amount is larger than the second force amount.
    Type: Application
    Filed: October 23, 2017
    Publication date: February 15, 2018
    Applicant: OLYMPUS CORPORATION
    Inventor: Yasuhiro OKAMOTO
  • Publication number: 20180026099
    Abstract: Properties of a semiconductor device are improved. A semiconductor device is configured so as to include a voltage clamp layer, a channel underlayer, a channel layer, and a barrier layer, which are formed in order above a substrate, a trench that extends up to the middle of the channel layer while penetrating through the barrier layer, a gate electrode disposed within the trench with a gate insulating film in between, a source electrode and a drain electrode formed above the barrier layer on both sides of the gate electrode, and a fourth electrode electrically coupled to the voltage clamp layer. The fourth electrode is electrically isolated from the source electrode, and a voltage applied to the fourth electrode is different from a voltage applied to the source electrode. Consequently, threshold control can be performed. For example, a threshold of a MISFET can be increased.
    Type: Application
    Filed: May 25, 2017
    Publication date: January 25, 2018
    Applicant: Renesas Electronics Corporation
    Inventors: Hironobu MIYAMOTO, Tatsuo NAKAYAMA, Atsushi TSUBOI, Yasuhiro OKAMOTO, Hiroshi KAWAGUCHI
  • Patent number: 9861264
    Abstract: A rigid endoscope includes a first insertion section extending along longitudinal directions, a first needle defining an outer edge of a first opening, and a first functional section provided in a vicinity of the first opening of a first lumen, and configured to perform some part of functions. The rigid endoscope includes a second insertion section extending along the longitudinal directions, and located apart from the first insertion section in directions perpendicular to the longitudinal directions, a second needle defining an outer edge of a second opening, and a second functional section provided in a vicinity of the second opening of a second lumen, and configured to perform some part of the functions different from the functions performed by the first functional section.
    Type: Grant
    Filed: July 20, 2012
    Date of Patent: January 9, 2018
    Assignee: OLYMPUS CORPORATION
    Inventors: Yasuhiro Okamoto, Kazuo Banju, Hiroki Moriyama
  • Publication number: 20170358652
    Abstract: In order to improve the characteristics of a semiconductor device including: a channel layer and a barrier layer formed above a substrate; and a gate electrode arranged over the barrier layer via a gate insulating film, the semiconductor device is configured as follows. A silicon nitride film is provided over the barrier layer between a source electrode and the gate electrode, and is also provided over the barrier layer between a drain electrode and the gate electrode GE. The surface potential of the barrier layer is reduced by the silicon nitride film, thereby allowing two-dimensional electron gas to be formed. Thus, by selectively forming two-dimensional electron gas only in a region where the silicon nitride film is formed, a normally-off operation can be performed even if a trench gate structure is not adopted.
    Type: Application
    Filed: August 7, 2017
    Publication date: December 14, 2017
    Inventor: Yasuhiro OKAMOTO
  • Patent number: 9837519
    Abstract: The semiconductor device includes a trench that penetrates a barrier layer, and reaches a middle portion of a channel layer among an n+ layer, an n-type layer, a p-type layer, the channel layer, and the barrier layer which are formed above a substrate, a gate electrode arranged within the groove through a gate insulating film, and a source electrode and a drain electrode which are formed above the barrier layer on both sides of the gate electrode. The n-type layer and the drain electrode are electrically coupled by a connection portion that reaches the n+ layer. The p-type layer and the source electrode are electrically coupled by a connection portion that reaches the p-type layer. A diode including a p-type layer and an n-type layer is provided between the source electrode and the drain electrode, to thereby prevent the breaking of an element caused by an avalanche breakdown.
    Type: Grant
    Filed: November 8, 2016
    Date of Patent: December 5, 2017
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Tatsuo Nakayama, Hironobu Miyamoto, Yasuhiro Okamoto, Yoshinao Miura, Takashi Inoue