Toyota Jidosha Kabushiki Kaisha

Nippon Steel Sumitomo Metal Corporation

Kyoto University

Denso Corporation

Katsunori Danno

Kazuhito Kamei

Kazuhiko Kusunoki

Hironori Daikoku

Tetsuya Shoji

Akinori Seki

Tsunenobu Kimoto

Kazuaki Seki

Hiroaki Saitoh

Masayoshi Doi

Yusuke Yamashita

Nobuhiro Okada

Noritsugu Sakuma

Masaaki Ito

Daisuke Ichigozaki

Motohisa Kado

Kensaku Yamamoto

Nobuyoshi Yashiro

Akihito Kinoshita

Takayuki Shirai

Toshimasa Hara

Hayate Yamano

Reimi Sakaguchi

Kouji Moriguchi

Yoichiro Kawai

The present disclosure provides a rare earth magnet having a main phase and a grain boundary phase and a manufacturing method therefor. In the rare earth magnet of the present disclosure, the overall composition is represented by a formula (RLaCe)(FeCo)BM. (Ris a predetermined rare earth element, Mis a predetermined element, and the followings are satisfied, 0.05≤x≤0.25, 0.5≤y/(x+y)≤0.50, 13.5≤u≤20.0, 0≤z≤0.100, 5.0≤w≤10.0, and 0≤v≤2.00). The main phase has an RFeB-type crystal structure, and the average grain size and the volume fraction of the main phase are respectively 1.0 μm to 20.0 μm and 80.0% to 90.0%. The main phase and the grain boundary phase satisfy, (the existence proportion of La in the grain boundary phase)/(the existence proportion of La in the main phase)>1.30.

Rare earth magnet and manufacturing method therefor

The present disclosure relates to a semiconductor device including an n-type gallium oxide semiconductor layer that has a center region and a peripheral region having a lower donor density than the center region, an electrode layer that is laminated on the n-type gallium oxide semiconductor layer, and forms Schottky junction with the n-type gallium oxide semiconductor layer in the center region as viewed from a lamination direction, and a first p-type nickel oxide semiconductor layer that is laminated on the n-type gallium oxide semiconductor layer such that the first p-type nickel oxide semiconductor layer is partially positioned between the n-type gallium oxide semiconductor layer and the electrode layer, and has an outer peripheral end portion on a peripheral region side in the peripheral region as viewed from the lamination direction.

Semiconductor device and method of manufacturing semiconductor device

In a semiconductor device, p-type semiconductor layers are stacked on a first surface side of n-type gallium oxide semiconductor layer such that the p-type semiconductor layers are in contact with the n-type gallium oxide semiconductor layer; a first electrode layer is stacked on the first surface side of the n-type gallium oxide semiconductor layer such that the first electrode layer is in contact with the p-type semiconductor layers and is in contact with the n-type gallium oxide semiconductor layer in a portion where the p-type semiconductor layers are distant from each other; a second electrode layer is stacked on a second surface side of the n-type gallium oxide semiconductor layer such that the second electrode layer is in contact with the n-type gallium oxide semiconductor layer; and a shortest distance between two p-type semiconductor layers that are most adjacent to each other is 0.4 μm to 1.0 μm.

Semiconductor device

The present disclosure provides a method for producing a semiconductor element that can lower the potential risk of malfunction. The production method of the disclosure is a method for producing a semiconductor element which includes providing a semiconductor element precursor, the precursor having a metal electrode layer formed on the surface of a gallium oxide-based single crystal semiconductor layer and a dopant doped in at least part of an exposed portion on the surface of the gallium oxide-based single crystal semiconductor layer where the metal electrode layer is not layered, and annealing treatment of the semiconductor element precursor whereby the dopant is diffused to a portion of the gallium oxide-based single crystal semiconductor layer that are overlapping with the metal electrode layer in the layering direction, to form a Schottky junction between the gallium oxide-based single crystal semiconductor layer and the metal electrode layer.

Method for producing semiconductor element

A switching element may include a SiC substrate including an off-angle; a trench provided in an upper surface of the SiC substrate and extending along an off-direction of the SiC substrate in a plan view of the upper surface; a gate insulating film; and a gate electrode. The SiC substrate may include a source region of n-type; a contact region of p-type; a body region of p-type being in contact with the gate insulating film below the source region; a drift region of n-type being in contact with the gate insulating film below the body region; and low lifetime regions located in a range between the drift region and at least one of the source region and the contact region. The low lifetime regions may be arranged along the off-direction with intervals, and at least a part of the body region may be provided in the intervals.

Switching element and method of manufacturing the same

A high-quality SiC single crystal and a method for producing such a SiC single crystal is provided. In the SiC single crystal, the threading dislocation density including screw dislocation, edge dislocation and micropipe defect is reduced. The method for producing the SiC single crystal according to a solution technique involves bringing an SiC seed crystal into contact with an Si&#x2014;C solution having a temperature gradient in which a temperature of the Si&#x2014;C solution is lower towards the surface of the SiC seed crystal. Growing an SiC single crystal includes setting the temperature gradient of the surface region of the Si&#x2014;C solution to 10&#xb0; C/cm or below, bringing the (1-100) face of the SiC seed crystal into contact with the Si&#x2014;C solution, and growing an SiC single crystal on the (1-100) face of the seed crystal at a ratio (single crystal growth rate/temperature gradient) of less than 20&#xd7;10cm/h&#xb7;&#xb0; C.

SiC single crystal and production method thereof

A method for producing a SiC single crystal with few dislocations and defects and a large diameter enlargement ratio is provided. A method for producing a SiC single crystal by solution process, wherein a bottom face of a seed crystal is (0001) or (000-1) face and has circular shape with at least a partially removed section and a circular arc-shaped section on an outer periphery, the number of the removed sections is one or more, shapes of the removed sections are bow-shaped with a minor arc or semi-circumference removed along a chord connecting two points on the circular arc, a central angle formed by a center of the circular shape and the two points is 40&#xb0; or greater, and a total of the central angles of the removed sections is no greater than 180&#xb0;, the method comprising forming a meniscus and growing the single crystal from the bottom face.

Method for producing silicon carbide single crystal in a solution process using a seed crystal having a bottom face with a circular shape and at least a partially removed section

Provided is a method for producing a SiC single crystal which can suppress generation of SiC polycrystals. The method according to the present embodiment is in accordance with a solution growth method. The method for producing a SiC single crystal according to the present embodiment comprises a power-output increasing step, a contact step, and a growth step. In the power-output increasing step, high-frequency power output of an induction heating device is increased to crystal-growth high-frequency power output. In the contact step, a SiC seed crystal is brought into contact with a Si&#x2014;C solution. The high-frequency power output of the induction heating device in the contact step is more than 80% of the crystal-growth high-frequency power output. The temperature of the Si&#x2014;C solution in the contact step is less than a crystal growth temperature. In the growth step, the SiC single crystal is grown at the crystal growth temperature.

Method for producing SiC single crystal

A production method according an embodiment of the present invention is to produce a SiC single crystal by a solution growth technique, and includes a formation step and a growth step. In the formation step, material of Si&#x2014;C solution contained in a crucible is melted, and a Si&#x2014;C solution is formed. In the growth step, a SiC seed crystal attached to a bottom end of a seed shaft is brought into contact with the Si&#x2014;C solution, and a SiC single crystal is grown on a crystal growth surface of the SiC seed crystal. In the growth step, while a temperature of the Si&#x2014;C solution is being raised, the SiC single crystal is grown. The SiC single crystal production method according to the embodiment facilitates production of a SiC single crystal of a desired polytype.

A SiC single crystal comprising no polycrystals, and no cracking other than at the side edges is provided. A method for producing SiC single crystal in which seed crystal held at bottom end face of holding shaft is contacted with Si&#x2014;C solution having temperature gradient to grow SiC single crystal, wherein the contour of the end face of the holding shaft is smaller than the contour of the top face of the seed crystal, the top face of the seed crystal has center section held in contact with the entire surface of the end face of the holding shaft and outer peripheral section that is not in contact with the end face of the holding shaft, and carbon sheet is disposed on the top face of the seed crystal so as to cover at least the outer peripheral section, among the center section and the outer peripheral section.

SiC single crystal and method for producing same

A SiC single crystal having high crystallinity and a large diameter is provided. A SiC single crystal comprising a seed crystal with a c-plane and a non-c-plane, and a c-plane growth portion and an enlarged diameter portion that have grown from the c-plane and the non-c-plane of the seed crystal as origins in the direction of the c-plane and the direction of the non-c-plane, wherein a continuous region free of threading dislocations is present in a peripheral portion of a plane that is parallel to the c-plane of the seed crystal, and contains the seed crystal and the enlarged diameter portion, wherein the area of the continuous region occupies 50% or more of the total area of the plane.

SiC single crystal and method of producing same

A SiC single crystal having low density of threading screw dislocations, threading edge dislocations, micropipe defects, base plane dislocations and stacking faults is provided. This is achieved by a method for producing a SiC single crystal in which a SiC seed crystal substrate is contacted with a Si&#x2014;C solution having a temperature gradient such that the temperature decreases from the interior toward the surface, to grow a SiC single crystal, the method including: a first step in which a SiC single crystal is grown with a (1-100) plane as the growth surface, a second step in which a {0001} plane is exposed from the grown SiC single crystal, and a third step in which the SiC single crystal having the exposed {0001} plane is used as a seed crystal, and the {0001} plane is used as the growth surface for growth of a SiC single crystal.

Method for producing sic single crystal having low defects by solution process

Provided is a method for producing a SiC single crystal wherein generation of polycrystals can be inhibited even if the temperature of the Si&#x2014;C solution is changed after seed touching. This is achieved by a method for producing a SiC single crystal wherein a SiC seed crystal substrate held on a seed crystal holding shaft is contacted with a Si&#x2014;C solution having a temperature gradient in which the temperature decreases from the interior toward the surface, to grow a SiC single crystal, comprising the steps of: (A) bringing the temperature of the solution to a first temperature, (B) contacting the substrate held on the holding shaft with the solution, (C) bringing the temperature of the solution to a second temperature after the contacting the substrate with the solution, and (D) moving the substrate held on the holding shaft in the vertical direction according to the change in liquid surface height of the solution when the temperature of the solution is brought from the first temperature to the second temperature.

A method for producing a SiC substrate with an epitaxial layer, which can prevent inventory of wafers from unduly increasing and wasteful production, is provided. This is achieved by a method for producing a SiC substrate with an epitaxial layer one at a time, the method comprising growing an epitaxial layer and growing a SiC substrate on a seed crystal substrate, and the method further comprising removing the obtained SiC substrate with the epitaxial layer from the seed crystal substrate.

Method for producing SiC substrate

A method for producing a SiC single crystal, comprising using a Si&#x2014;C solution having a temperature gradient in which the temperature decreases from the interior toward the surface to grow a SiC single crystal from a seed crystal substrate, wherein the Si&#x2014;C solution includes Si and Cr, the boron density difference Bs&#x2212;Bg between the boron density Bs in the seed crystal substrate and the boron density Bg in the growing single crystal is 1&#xd7;10/cmor greater, the chromium density difference Crg&#x2212;Crs between the chromium density Crs in the seed crystal substrate and the chromium density Crg in the growing single crystal is 1&#xd7;10/cmor greater, and the nitrogen density difference Ng&#x2212;Ns between the nitrogen density Ns in the seed crystal substrate and the nitrogen density Ng in the growing single crystal is 3.5&#xd7;10/cmto 5.8&#xd7;10/cm.

Growing community of inventors

Susono, Japan

Katsunori Danno