Sumitomo Electric Industries, Limited

Sony Corporation

Tohoku University

Other

Institute of Materials Research and Engineering

Masaki Ueno

Yusuke Yoshizumi

Takashi Kyono

Yohei Enya

Takamichi Sumitomo

Katsushi Akita

Takao Nakamura

Koji Katayama

Takatoshi Ikegami

Shimpei Takagi

Masahiro Adachi

Shinji Tokuyama

Kensaku Motoki

Katsunori Yanashima

Masaya Okada

Fuminori Mitsuhashi

Eiryo Takasuka

Yasunori Tateno

Hiroshi Nakajima

Toshio Ueda

Maki Suemitsu

Hirokazu Fukidome

Fumitake Nakanishi

Kunihiko Tasai

Makoto Kiyama

Toshiyuki Kuramoto

Ryu Hirota

Yu Saitoh

Takashi Ishizuka

Hiroyuki Nagasawa

Takahisa Yoshida

Hideaki Nakahata

Seiji Nakahata

Keiji Ishibashi

Koji Uematsu

Akihiro Hachigo

Takashi Matsuura

Tatsushi Hamaguchi

Noriyuki Futagawa

Kei Fujii

Masahiro Nakayama

Kazutaka Inoue

Seiji Yaegashi

Kazuhide Sumiyoshi

Yoshihiro Saito

Nobuhiro Saga

Hideki Osada

Kouhei Miura

Peng Chen

Kuniaki Ishihara

Yoko Watanabe

Yuji Furushima

Tetsuya Kumano

Mitsunori Yokoyama

Soo-Jin Chua

Manabu Okui

Yoshihiro Tsukuda

A stacked body includes: a substrate made of silicon carbide and having a first main surface forming an angle of 20&#xb0; or less with a silicon plane; and a graphene film disposed on the first main surface and having an atomic arrangement oriented in relation to an atomic arrangement of silicon carbide forming the substrate. In an exposed surface of the graphene film which is a main surface opposite to the substrate, an area ratio of a region having a full width at half maximum of G' of 40 cmor less under Raman spectroscopy analysis is 50% or more. Accordingly, the stacked body is provided that enables a high mobility to be stably ensured in an electronic device manufactured to include the graphene film forming an electrically conductive portion.

Stacked body including graphene film and electronic device including graphene film

A stacked body includes: a substrate made of silicon carbide and having a first main surface forming an angle of 20&#xb0; or less with a carbon plane; and a graphene film disposed on the first main surface and having an atomic arrangement oriented in relation to an atomic arrangement of silicon carbide forming the substrate. In an exposed surface of the graphene film as seen in plan view, 10 or less regions are present per 1 mm, the exposed surface being a main surface opposite to the substrate, and the regions each including 10 or more graphene layers and having a circumcircle with a diameter of 5 &#x3bc;m or more and 100 &#x3bc;m or less. Accordingly, the stacked body is provided that enables a high mobility to be stably ensured in an electronic device manufactured to include the graphene film forming an electrically conductive portion.

Stacked body and electronic device

A silicon carbide (SiC) structure and a method of forming the SiC structure are disclosed. The SiC structure includes an SiC substrate and a film provided on the SiC substrate. The SiC substrate contains both of a hexagonal close packed (hcp) structure and a face centered cubic (fcc) structure, and has only one of the hcp surface and the fcc surface, where the hcp surface includes atoms in the topmost layer whose rows overlap with rows of atoms in the third layer, while, the fcc surface includes atoms in the topmost layer whose rows are different from rows of atoms in the third layer.

SiC structure, semiconductor device having SiC structure, and process of forming the same

An electron device having a channel layer made of graphene is disclosed. The electron device includes a graphene layer on a substrate, and a source electrode, a drain electrode, and a gate insulating film on the graphene layer. The electron device further includes a first gate electrode on the gate insulating film between the source electrode and the drain electrode, and a second gate electrode within the substrate. For the second gate electrode, another gate insulating film is on the graphene layer, or alternatively, a part of the substrate is interposed between the second gate electrode and the channel layer.

Semiconductor device

A substrate includes: a support substrate having a first main surface and a surface layer region which includes at least the first main surface and is formed of any one material selected from the group consisting of boron nitride, molybdenum disulfide, tungsten disulfide, niobium disulfide, and aluminum nitride; and a graphene film disposed on the first main surface and having an atomic arrangement oriented in relation to an atomic arrangement of the material forming the surface layer region. Accordingly, the substrate is provided that enables a high mobility to be stably ensured in an electronic device manufactured to include the graphene film forming an electrically conductive portion.

Substrate and electronic device

A layered semiconductor includes a base layer including a substrate and a buffer layer, and a drift layer which is disposed on the base layer and is made of GaN and whose conductivity type is an n-type. The drift layer has an average n-type impurity concentration of 1.5&#xd7;10cmor less in a radial direction of the substrate, and the difference between the maximum n-type impurity concentration and the minimum n-type impurity concentration is 1.5&#xd7;10cmor less.

Layered semiconductor having base layer including GaN substrate

A laminated body includes: a substrate portion composed of silicon carbide; and a graphene film disposed on a first main surface of the substrate portion, the graphene film having an atomic arrangement oriented with respect to an atomic arrangement of the silicon carbide of the substrate portion. A region in which a value of G'/G in Raman spectrometry is not less than 1.2 is not less than 10% in an area ratio in an exposed surface of the graphene film, the exposed surface being a main surface of the graphene film opposite to the substrate portion.

Laminated body and electronic device

A method of fabricating a single crystal gallium nitride substrate the step of cutting an ingot of single crystal gallium nitride along predetermined planes to make one or more signal crystal gallium nitride substrates. The ingot of single crystal gallium nitride is grown by vapor phase epitaxy in a direction of a predetermined axis. Each predetermined plane is inclined to the predetermined axis. Each substrate has a minor polished primary surface. The primary surface has a first area and a second area. The first area is between an edge of the substrate and a line 3 millimeter away from the edge. The first area surrounds the second area. An qaxis perpendicular to the primary surface forms an off-angle with c-axis of the substrate. The off-angle takes a minimum value at a first position in the first area of the primary surface.

Gallium nitride semiconductor substrate with semiconductor film formed therein

A Group III nitride semiconductor device comprises: a Group III nitride semiconductor layer having a primary surface, inclined with respect to a c-plane of the Group III nitride semiconductor at an angle in a range of 50 degrees or more and 80 degrees or less, of a Group III nitride semiconductor; a p-type Group III nitride semiconductor laminate including first to third p-type Group III nitride semiconductor layers, the first to third p-type Group III nitride semiconductor layers being provided on the primary surface of the Group III nitride semiconductor layer, the first and third p-type Group III nitride semiconductor layers sandwiching the second p-type Group III nitride semiconductor layer such that the second p-type Group III nitride semiconductor layer incorporates strain; and an electrode provided on the p-type Group III nitride semiconductor laminate. The electrode is in contact with the first p-type Group III nitride semiconductor layer.

Group III nitride semiconductor device, p-type contact structure, and method for fabricating group III nitride semiconductor device

Disclosed is a gallium nitride crystal substrate having a top surface, a bottom surface, regions of higher oxygen concentrations measured by SIMS, and other regions of lower oxygen concentrations measured by SIMS. The top surface is a C-plane surface. The ratio of the highest oxygen concentration to the lowest oxygen concentration is equal to or more than fifty.

Oxygen-doped gallium nitride crystal substrate

A method of fabricating a single crystal gallium nitride substrate the step of cutting an ingot of single crystal gallium nitride along predetermined planes to make one or more signal crystal gallium nitride substrates. The ingot of single crystal gallium nitride is grown by vapor phase epitaxy in a direction of a predetermined axis. Each predetermined plane is inclined to the predetermined axis. Each substrate has a minor polished primary surface. The primary surface has a first area and a second area. The first area is between an edge of the substrate and a line 3 millimeter away from the edge. The first area surrounds the second area. An axis perpendicular to the primary surface forms an off-angle with c-axis of the substrate. The off-angle takes a minimum value at a first position in the first area of the primary surface.

A group III nitride semiconductor laser device includes a laser structure, an insulating layer, an electrode and dielectric multilayers. The laser structure includes a semiconductor region on a semi-polar primary surface of a hexagonal group III nitride semiconductor support base. The dielectric multilayers are on first and second end-faces for the laser cavity. The c-axis of the group III nitride tilts by an angle ALPHA from the normal axis of the primary surface in the waveguide axis direction from the first end-face to the second end-faces. A pad electrode has first to third portions provided on the first to third regions of the semiconductor regions, respectively. An ohmic electrode is in contact with the third region through an opening of the insulating layer. The first portion has a first arm, which extends to the first end-face edge. The third portion is away from the first end-face edge.

Group III nitride semiconductor light emitting device

There are provided a semiconductor device in which a drain leak current can be reduced in the transistor operation while high vertical breakdown voltage is achieved and a method for producing the semiconductor device. In the semiconductor device, an openingthat extends from an n-type contact layerand reaches an n-type drift layerthrough a p-type barrier layeris formed. The semiconductor device includes a regrown layerlocated so as to cover portions of the p-type barrier layerand the like that are exposed to the opening, the regrown layerincluding an undoped GaN channel layerand a carrier supply layer; an insulating layerlocated so as to cover the regrown layer; and a gate electrode G located on the insulating layer. In the p-type barrier layer, the Mg concentration A (cm)and the hydrogen concentration B (cm) satisfy 0.1&#x3c;B/A&#x3c;0.9 . . . (1).

Semiconductor device including GaN-based compound semiconductor stacked layer and method for producing the same

A vertical semiconductor device in which pinch-off characteristics and breakdown voltage characteristics can be stably improved by fixing the electric potential of a p-type GaN barrier layer with certainty is provided. The semiconductor device includes a GaN-based stacked layer having an opening, a regrown layer including a channel located so as to cover a wall surface of the opening, an n-type source layer that is in ohmic contact with the source electrode, a p-type GaN barrier layer, and a p-type GaN-based supplementary layer located between the p-type GaN barrier layer and the n-type source layer. The p-type GaN-based supplementary layer and the n-type source layer form a tunnel junction to fix the electric potential of the p-type GaN barrier layer at a source potential.

Vertical GaN-based semiconductor device

A Group III nitride semiconductor laser device includes a laser structure including a support substrate with a semipolar primary surface of a hexagonal Group III nitride semiconductor, and a semiconductor region thereon, and an electrode, provided on the semiconductor region, extending in a direction of a waveguide axis in the laser device. The c-axis of the nitride semiconductor is inclined at an angle ALPHA relative to a normal axis to the semipolar surface toward the waveguide axis direction. The laser structure includes first and second fractured faces intersecting with the waveguide axis. A laser cavity of the laser device includes the first and second fractured faces extending from edges of first and second faces. The first fractured face includes a step provided at an end face of an InGaN layer of the semiconductor region and extending in a direction from one side face to the other of the laser device.

III-nitride semiconductor laser device and method for fabricating III-nitride semiconductor laser device

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Itami, Japan

Masaki Ueno