Patents by Inventor Shoichi Onda
Shoichi Onda 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: 20240014272Abstract: A semiconductor device includes a gallium nitride substrate and a pattern film disposed on a front surface of the gallium nitride substrate. In the gallium nitride substrate, a Young's modulus in a first direction along the front surface is larger than a Young's modulus in a second direction along the front surface and orthogonal to the first direction. A first ratio R1 obtained by dividing a dimension of the gallium nitride substrate in the first direction by a dimension of the gallium nitride substrate in the second direction and a second ratio R2 obtained by dividing a dimension of the pattern film in the first direction by a dimension of the pattern film in the second direction satisfy a relationship of R1<R2.Type: ApplicationFiled: July 3, 2023Publication date: January 11, 2024Inventors: Seiya HASEGAWA, Takashi USHIJIMA, Takashi ISHIDA, Shoichi ONDA, Chiaki SASAOKA, Jun KOJIMA
-
Patent number: 11810783Abstract: A gallium nitride semiconductor device includes: a chip formation substrate made of gallium nitride and having one surface and an other surface opposite to the one surface; a one surface side element component disposed on the one surface and providing a component of an one surface side of a semiconductor element; and a metal film constituting a back surface electrode in contact with the other surface. The other surface has an irregularity provided by a plurality of convex portions with a trapezoidal cross section and a plurality of concave portions located between the convex portions; and an upper base surface of the trapezoidal cross section in each of the plurality of convex portions is opposed to the one surface.Type: GrantFiled: April 13, 2021Date of Patent: November 7, 2023Assignees: DENSO CORPORATION, HAMAMATSU PHOTONICS K.K., National University Corporation Tokai National Higher Education and Research SystemInventors: Chiaki Sasaoka, Jun Kojima, Shoichi Onda, Masatake Nagaya, Kazukuni Hara, Daisuke Kawaguchi
-
Patent number: 11810821Abstract: A semiconductor chip includes: an epitaxial film made of gallium nitride; a semiconductor element disposed in the epitaxial film; a chip formation substrate including the epitaxial film and having a first surface, a second surface opposite to the first surface, and a side surface connecting the first surface and the second surface; and a convex and a concavity on the side surface.Type: GrantFiled: April 13, 2021Date of Patent: November 7, 2023Assignees: DENSO CORPORATION, HAMAMATSU PHOTONICS K.K., National University Corporation Tokai National Higher Education and Research SystemInventors: Masatake Nagaya, Kazukuni Hara, Daisuke Kawaguchi, Toshiki Yui, Chiaki Sasaoka, Jun Kojima, Shoichi Onda
-
Publication number: 20230326748Abstract: A manufacturing method of a semiconductor device, includes: forming a gas vent recess in a first surface of a compound semiconductor substrate, which includes a plurality of device regions adjacent to the first surface, along an interface between the plurality of device regions; forming an altered layer inside the compound semiconductor substrate to extend along the first surface at a depth corresponding to a range of a depth of the gas vent recess by applying a laser beam; dividing the compound semiconductor substrate at the altered layer into a first part including the first surface and a second part including a second surface of the compound semiconductor substrate opposite to the first surface; and forming a metal film to cover a divided surface of the first part while exposing the gas vent recess.Type: ApplicationFiled: March 23, 2023Publication date: October 12, 2023Inventors: SHOSUKE NAKABAYASHI, MASATAKE NAGAYA, CHIAKI SASAOKA, SHOICHI ONDA, JUN KOJIMA, DAISUKE KAWAGUCHI, RYUJI SUGIURA, TOSHIKI YUI, KEISUKE HARA, TOMOMI ARATANI
-
Patent number: 11784039Abstract: A method for manufacturing a gallium nitride semiconductor device includes: preparing a gallium nitride wafer; forming an epitaxial growth film on the gallium nitride wafer to provide a processed wafer having chip formation regions; perform a surface side process on a one surface side of the processed wafer; removing the gallium nitride wafer and dividing the processed wafer into a chip formation wafer and a recycle wafer; and forming an other surface side element component on an other surface side of the chip formation wafer.Type: GrantFiled: April 13, 2021Date of Patent: October 10, 2023Assignees: DENSO CORPORATION, HAMAMATSU PHOTONICS K.K., National University Corporation Tokai National Higher Education and Research SystemInventors: Jun Kojima, Chiaki Sasaoka, Shoichi Onda, Masatake Nagaya, Kazukuni Hara, Daisuke Kawaguchi
-
Publication number: 20230238281Abstract: A method of manufacturing a gallium nitride substrate includes preparation of a gallium nitride wafer, formation of a transformation layer, and formation of the gallium nitride substrate. The gallium nitride has a first main surface and a second main surface on a side opposite from the first main surface. The gallium nitride wafer is made of a hexagonal crystal, and each of the first main surface and the second main surface is a {1-100} m-plane of the hexagonal crystal. The transformation layer is formed along a planar direction of the gallium nitride wafer by emitting a laser beam into the gallium nitride wafer. The gallium nitride substrate is formed from the gallium nitride wafer by dividing the gallium nitride wafer at the transformation layer. In the formation of the transformation layer, the laser beam is emitted to form an irradiation mark for forming the transformation layer.Type: ApplicationFiled: January 12, 2023Publication date: July 27, 2023Inventors: MASATAKE NAGAYA, SHOSUKE NAKABAYASHI, DAISUKE KAWAGUCHI, TOSHIKI YUI, CHIAKI SASAOKA, SHOICHI ONDA, JUN KOJIMA
-
Publication number: 20230230829Abstract: A method of manufacturing a semiconductor element includes formation of a modified layer, detection of a first region, and cutting of a semiconductor wafer. In the formation of the modified layer, a laser is irradiated on the semiconductor wafer to form the modified layer extending along a surface of the semiconductor wafer inside the semiconductor wafer. The surface of the semiconductor wafer includes a peripheral portion having the first region and a second region. The first region is a region in which the modified layer is not located, and the second region is a region in which the modified layer is formed. In the cutting of the semiconductor wafer, the semiconductor wafer is cut at the modified layer starting from the second region.Type: ApplicationFiled: December 29, 2022Publication date: July 20, 2023Inventors: SHOSUKE NAKABAYASHI, JUNJI OHARA, MASATAKE NAGAYA, CHIAKI SASAOKA, SHOICHI ONDA, JUN KOJIMA, DAISUKE KAWAGUCHI, RYUJI SUGIURA, TOSHIKI YUI, KEISUKE HARA
-
Publication number: 20230160104Abstract: A method for manufacturing a semiconductor device includes: preparing a processed wafer having a gallium nitride (GaN) wafer and an epitaxial layer on the GaN wafer; forming a device constituent part in a portion of the processes wafer adjacent to a front surface provided by the epitaxial layer; forming a modified layer inside of the processed wafer by applying a laser beam from a back surface side opposite to the front surface side: and dividing the processed wafer at the modified layer. The processed wafer prepared includes a reflective layer for reflecting the laser beam at a position separated from a planned formation position, where the modified layer is to be formed, by a predetermined distance toward the front surface side. The reflective layer contains a layer having a refractive index different from that of a GaN single crystal of an epitaxial layer.Type: ApplicationFiled: November 16, 2022Publication date: May 25, 2023Inventors: Junji OHARA, Takashi ISHIDA, Yoshitaka NAGASATO, Daisuke KAWAGUCHI, Chiaki SASAOKA, Shoichi ONDA, Jun KOJIMA
-
Publication number: 20230116302Abstract: A semiconductor chip includes a chip-constituting substrate having one surface, the other surface opposite to the one surface, and two pairs of opposing side surfaces connecting the one surface and the other surface. The one surface and the other surface are along one of a {0001} c-plane, a {1-100} m-plane, and a {11-20} a-plane. One of the two pairs of opposing side surfaces is along another one of the {0001} c-plane, the {1-100} m-plane, and the {11-20} a-plane. The other of the two pairs of opposing side surfaces is along the other of the {0001} c-plane, the {1-100} m-plane, and the {11-20} a-plane. The side surface includes an altered layer containing gallium oxide and gallium metal in a surface layer portion in a depth direction which is a normal direction to the side surface.Type: ApplicationFiled: September 20, 2022Publication date: April 13, 2023Inventors: MASATAKE NAGAYA, Hiroki Watanabe, Junji Ohara, Daisuke Kawaguchi, Keisuke Hara, Chiaki Sasaoka, Jun Kojima, Shoichi Onda
-
Publication number: 20210327702Abstract: A method for manufacturing a gallium nitride semiconductor device includes: preparing a gallium nitride wafer; forming an epitaxial growth film on the gallium nitride wafer to provide a processed wafer having chip formation regions; perform a surface side process on a one surface side of the processed wafer; removing the gallium nitride wafer and dividing the processed wafer into a chip formation wafer and a recycle wafer; and forming an other surface side element component on an other surface side of the chip formation wafer.Type: ApplicationFiled: April 13, 2021Publication date: October 21, 2021Inventors: Jun KOJIMA, Chiaki SASAOKA, Shoichi ONDA, Masatake NAGAYA, Kazukuni HARA, Daisuke KAWAGUCHI
-
Publication number: 20210327710Abstract: A gallium nitride semiconductor device includes: a chip formation substrate made of gallium nitride and having one surface and an other surface opposite to the one surface; a one surface side element component disposed on the one surface and providing a component of an one surface side of a semiconductor element; and a metal film constituting a back surface electrode in contact with the other surface. The other surface has an irregularity provided by a plurality of convex portions with a trapezoidal cross section and a plurality of concave portions located between the convex portions; and an upper base surface of the trapezoidal cross section in each of the plurality of convex portions is opposed to the one surface.Type: ApplicationFiled: April 13, 2021Publication date: October 21, 2021Inventors: Chiaki SASAOKA, Jun KOJIMA, Shoichi ONDA, Masatake NAGAYA, Kazukuni HARA, Daisuke KAWAGUCHI
-
Publication number: 20210327757Abstract: A semiconductor chip includes: an epitaxial film made of gallium nitride; a semiconductor element disposed in the epitaxial film; a chip formation substrate including the epitaxial film and having a first surface, a second surface opposite to the first surface, and a side surface connecting the first surface and the second surface; and a convex and a concavity on the side surface.Type: ApplicationFiled: April 13, 2021Publication date: October 21, 2021Inventors: Masatake Nagaya, Kazukuni Hara, Daisuke Kawaguchi, Toshiki Yui, Chiaki Sasaoka, Jun Kojima, Shoichi Onda
-
Patent number: 10253431Abstract: A silicon carbide single crystal includes a spiral dislocation. The spiral dislocation includes a L dislocation having a burgers vector defined as b, which satisfies an equation of b><0001>+1/3<11-20>. The L dislocation has a density equal to or lower than 300 dislocations/cm2, preferably, 100 dislocations/cm2, since the L dislocation has large distortion and causes generation of leakage current. Thus, the silicon carbide single crystal with high quality is suitable for a device production which can suppress the leakage current.Type: GrantFiled: January 13, 2014Date of Patent: April 9, 2019Assignee: DENSO CORPORATIONInventors: Hiroyuki Kondo, Shoichi Onda, Yasuo Kitou, Hiroki Watanabe
-
Patent number: 10181517Abstract: A silicon carbide single crystal includes: threading dislocations each of which having a dislocation line extending through a C-plane, and a Burgers vector including at least a component in a C-axis direction. In addition, a density of the threading dislocations having angles, each of which is formed by an orientation of the Burgers vector and an orientation of the dislocation line, larger than 0° and within 40° is set to 300 dislocations/cm2 or less. Furthermore, a density of the threading dislocations having the angles larger than 40° is set to 30 dislocations/cm2 or less.Type: GrantFiled: August 25, 2016Date of Patent: January 15, 2019Assignee: DENSO CORPORATIONInventors: Takeshi Okamoto, Hiroyuki Kondo, Takashi Kanemura, Shinichiro Miyahara, Yasuhiro Ebihara, Shoichi Onda, Hidekazu Tsuchida, Isaho Kamata, Ryohei Tanuma
-
Publication number: 20180219069Abstract: A silicon carbide single crystal includes: threading dislocations each of which having a dislocation line extending through a C-plane, and a Burgers vector including at least a component in a C-axis direction. In addition, a density of the threading dislocations having angles, each of which is formed by an orientation of the Burgers vector and an orientation of the dislocation line, larger than 0° and within 40° is set to 300 dislocations/cm2 or less. Furthermore, a density of the threading dislocations having the angles larger than 40° is set to 30 dislocations/cm2 or less.Type: ApplicationFiled: August 25, 2016Publication date: August 2, 2018Inventors: Takeshi OKAMOTO, Hiroyuki KONDO, Takashi KANEMURA, Shinichiro MIYAHARA, Yasuhiro EBIHARA, Shoichi ONDA, Hidekazu TSUCHIDA, Isaho KAMATA, Ryohei TANUMA
-
Publication number: 20150361586Abstract: A silicon carbide single crystal includes a spiral dislocation. The spiral dislocation includes a L dislocation having a burgers vector defined as b, which satisfies an equation of b><0001>+1/3<11-20>. The L dislocation has a density equal to or lower than 300 dislocations/cm2, preferably, 100 dislocations/cm2, since the L dislocation has large distortion and causes generation of leakage current. Thus, the silicon carbide single crystal with high quality is suitable for a device production which can suppress the leakage current.Type: ApplicationFiled: January 13, 2014Publication date: December 17, 2015Inventors: Hiroyuki KONDO, Shoichi ONDA, Yasuo KITOU, Hiroki WATANABE
-
Patent number: 7147714Abstract: When a SiC substrate is heated up to around 1800°C., sublimation of SiC occurs from the SiC substrate. Moreover, temperature of the front surface of the SiC substrate is lower than that of the back surface of the SiC substrate. Therefore, sublimation gas sublimed from a back-surface vicinity of the substrate, where temperature is high, moves to a front-surface vicinity of the substrate, where temperature is low, through the hollow micro-pipe defect. Epitaxial growth proceeds on the front surface of the substrate while the sublimation gas is recrystallized at the front-surface vicinity of the substrate, so that the micro-pipe defect is occluded.Type: GrantFiled: April 27, 2004Date of Patent: December 12, 2006Assignee: Denso CorporationInventors: Masami Naito, Kazukuni Hara, Fusao Hirose, Shoichi Onda
-
Patent number: 7112242Abstract: A crucible, which has first member and second cylindrical body, is disposed in a lower chamber. A pedestal is disposed inside the first member, and a seed crystal is fixed to the pedestal. A second heat insulator is provided between an inlet conduit and a crucible. A first heat insulator is provided at a halfway portion of the inlet conduit. With these heat insulators, a temperature gradient occurs in the inlet conduit at a portion thereof that is closer to the crucible. A mixture gas is introduced into the crucible. The mixture gas is heated up gradually when passing through the inlet conduit and is introduced into the crucible to form SiC single crystals in high quality.Type: GrantFiled: June 22, 2004Date of Patent: September 26, 2006Assignee: Denso CorporationInventors: Kazukuni Hara, Masao Nagakubo, Shoichi Onda
-
Patent number: 6830618Abstract: A crucible, which has first member and second cylindrical body, is disposed in a lower chamber. A pedestal is disposed inside the first member, and a seed crystal is fixed to the pedestal. A second heat insulator is provided between an inlet conduit and a crucible. A first heat insulator is provided at a halfway portion of the inlet conduit. With these heat insulators, a temperature gradient occurs in the inlet conduit at a portion thereof that is closer to the crucible. A mixture gas is introduced into the crucible. The mixture gas is heated up gradually when passing through the inlet conduit and is introduced into the crucible to form SiC single crystals in high quality.Type: GrantFiled: November 1, 2001Date of Patent: December 14, 2004Assignee: Denso CorporationInventors: Kazukuni Hara, Masao Nagakubo, Shoichi Onda
-
Publication number: 20040231583Abstract: A crucible, which has first member and second cylindrical body, is disposed in a lower chamber. A pedestal is disposed inside the first member, and a seed crystal is fixed to the pedestal. A second heat insulator is provided between an inlet conduit and a crucible. A first heat insulator is provided at a halfway portion of the inlet conduit. With these heat insulators, a temperature gradient occurs in the inlet conduit at a portion thereof that is closer to the crucible. A mixture gas is introduced into the crucible. The mixture gas is heated up gradually when passing through the inlet conduit and is introduced into the crucible to form SiC single crystals in high quality.Type: ApplicationFiled: June 22, 2004Publication date: November 25, 2004Inventors: Kazukuni Hara, Masao Nagakubo, Shoichi Onda