Abstract: A main object of the present disclosure is to provide an active material wherein an expansion upon intercalation of a metal ion such as a Li ion is suppressed. The present disclosure achieves the object by providing an active material comprising a silicon clathrate type crystal phase, and the active material includes a Na element, a Si element and a M element that is a metal element with an ion radius larger than the Si element, and a proportion of the M element to a total of the Si element and the M element is 0.1 atm % or more and 5 atm % or less.

Abstract: A main object of the present disclosure is to provide an active material wherein an expansion upon intercalation of a metal ion such as a Li ion is suppressed. The present disclosure achieves the object by providing an active material comprising a silicon clathrate type crystal phase, and the active material includes a Na element, a Si element and a M element that is a metal element with an ion radius larger than the Si element, and a proportion of the M element to a total of the Si element and the M element is 0.1 atm % or more and 5 atm % or less.

Abstract: A main object of the present disclosure is to provide an active material wherein an expansion upon intercalation of a metal ion such as a Li ion is suppressed. The present disclosure achieves the object by providing an active material comprising a silicon clathrate type crystal phase, and the active material includes a Na element, a Si element and a M element that is a metal element with an ion radius larger than the Si element, and a proportion of the M element to a total of the Si element and the M element is 0.1 atm % or more and 5 atm % or less.

Abstract: A method for a SiC single crystal that allow prolonged growth to be achieved are provided. A method for producing a SiC single crystal in which a seed crystal substrate held on a seed crystal holding shaft is contacted with a Si—C solution having a temperature gradient such that a temperature of the Si—C solution decreases from an interior of the Si—C solution toward a liquid level of the Si—C solution, in a graphite crucible, to grow a SiC single crystal, wherein the method comprises the steps of: electromagnetic stirring of the Si—C solution with an induction coil to produce a flow, and heating of a lower part of the graphite crucible with a resistance heater.

Abstract: A main object of the present disclosure is to provide an active material wherein an expansion upon intercalation of a metal ion such as a Li ion is suppressed. The present disclosure achieves the object by providing an active material comprising a silicon clathrate type crystal phase, and the active material includes a Na element, a Si element and a M element that is a metal element with an ion radius larger than the Si element, and a proportion of the M element to a total of the Si element and the M element is 0.1 atm % or more and 5 atm % or less.

Abstract: A method for a SiC single crystal that allow prolonged growth to be achieved are provided. A method for producing a SiC single crystal in which a seed crystal substrate held on a seed crystal holding shaft is contacted with a Si—C solution having a temperature gradient such that a temperature of the Si—C solution decreases from an interior of the Si—C solution toward a liquid level of the Si—C solution, in a graphite crucible, to grow a SiC single crystal, wherein the method comprises the steps of: electromagnetic stirring of the Si—C solution with an induction coil to produce a flow, and heating of a lower part of the graphite crucible with a resistance heater.

Abstract: Provided is a SiC single crystal that has a large growth thickness and contains no inclusions. A SiC single crystal grown by a solution process, wherein the total length M of the outer peripheral section formed by the {1-100} faces on the {0001} growth surface of the SiC single crystal, and the length P of the outer periphery of the growth surface of the SiC single crystal, satisfy the relationship M/P?0.70, and the length in the growth direction of the SiC single crystal is 2 mm or greater.

Abstract: 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—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—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.

Abstract: 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—C solution contained in a crucible is melted, and a Si—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—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—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.

Abstract: A method for a SiC single crystal that allow prolonged growth to be achieved are provided. A method for producing a SiC single crystal in which a seed crystal substrate held on a seed crystal holding shaft is contacted with a Si—C solution having a temperature gradient such that a temperature of the Si—C solution decreases from an interior of the Si—C solution toward a liquid level of the Si—C solution, in a graphite crucible, to grow a SiC single crystal, wherein the method comprises the steps of: electromagnetic stirring of the Si—C solution with an induction coil to produce a flow, and heating of a lower part of the graphite crucible with a resistance heater.

Abstract: An apparatus (10) for producing an SiC single crystal is used in the solution growth includes a seed shaft (28) and a crucible (14). The seed shaft (28) has a lower end surface (28S) to which an SiC seed crystal (32) is to be attached. The crucible (14) holds an Si—C solution (15). The seed shaft (28) includes a cylinder part (28A), a bottom part (28B), and a low heat conductive member (28C). The bottom part (28B) is located at the lower end of the cylinder part (28A) and has the lower end surface (28S). The low heat conductive member (28C) is arranged on the upper surface of the bottom part (28B) and has a thermal conductivity lower than that of the bottom part (28B). This production apparatus can make the temperature within the crystal growth surface of the SiC seed crystal less liable to vary.

Abstract: Provided is a method for producing a SiC single crystal having a concave growth surface and containing no inclusions, even when conducting large diameter crystal growth. This is achieved by a method for producing a SiC single crystal in which a seed crystal substrate held on a seed crystal holding shaft is contacted with a Si—C solution having a temperature gradient such that the temperature decreases from the interior toward the liquid level, to cause crystal growth of a SiC single crystal, wherein the seed crystal holding shaft has a shaft portion and a seed crystal holding portion at the bottom end of the shaft portion, and the ratio of the diameter D1 of the shaft portion to the diameter D2 of the seed crystal holding portion (D1/D2) is no greater than 0.28.

Abstract: 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—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—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.

Abstract: 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—C solution contained in a crucible is melted, and a Si—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—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—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.

Abstract: The production method of an SiC single crystal is a production method of an SiC single crystal by a solution growth process. The production method includes a contact step A, a contact step B, and a growth step. In the contact step A, a partial region of the principal surface is brought into contact with a stored Si—C solution. In the contact step B, a contact region between the principal surface and the stored Si—C solution expands, due to a wetting phenomenon, starting from an initial contact region which is the partial region brought into contact in the contact step A. In the growth step, an SiC single crystal is grown on the principal surface which is in contact with the stored Si—C solution.

Abstract: An apparatus for producing SiC single crystals where the quality of the SiC single crystals is improved, and a production method using such an apparatus are provided. The apparatus for producing SiC single crystals according to an embodiment of the present invention is employed to produce an SiC single crystal by the solution growth method. The production apparatus includes a crucible and a support shaft. The crucible accommodates an Si—C solution. The support shaft supports the crucible. The support shaft includes a heat removing portion for removing heat from a bottom portion of the crucible. The heat removing portion includes one of (a) a contact portion having a thermal conductivity not less than that of the bottom portion and contacting at least a portion of the bottom portion and (b) a space adjacent to at least a portion of the contact portion or the bottom portion.

Abstract: A method for producing a SiC single crystal by a solution process is provided, which allows generation of miscellaneous crystals to be reduced. Method for producing a SiC single crystal wherein a crucible has thickness Lu in horizontal direction at same height as liquid level of Si—C solution, and thickness Ld in horizontal direction at same height as bottom inner wall, Ld/Lu is 2.00 to 4.21, and thickness in horizontal direction of crucible monotonously increases between Lu and Ld from Lu toward Ld, wall thickness of crucible is 1 mm or greater, bottom thickness Lb in vertical direction of crucible is between 1 mm and 15 mm, bottom outer wall of crucible has flat section with area of 100 mm2 or greater, depth of Si—C solution from bottom inner wall is 30 mm or greater, and method includes heating and electromagnetic stirring Si—C solution with high-frequency coil.

Abstract: Provided is a method for producing a SiC single crystal wherein a 4H—SiC single crystal is grown by minimizing generation of polytypes other than 4H. A method for producing a SiC single crystal by a solution process, wherein a seed crystal is 4H—SiC, and a (000-1) face of the seed crystal is a growth surface, wherein the method includes: setting a temperature at a center section of a region of a surface of a Si—C solution where the growth surface of the seed crystal contacts to 1900° C. or higher, and limiting a ?Tc/?Ta to 1.7 or greater, wherein the ?Tc/?Ta is a ratio of a temperature gradient ?Tc between the center section and a location 10 mm below the center section in the vertical direction, with respect to a temperature gradient ?Ta between the center section and a location 10 mm from the center section in the horizontal direction.

Abstract: An object of the present invention is to provide a SIC single crystal production apparatus that stirs and heats a Si—C solution easily. The apparatus includes a crucible capable of containing a Si—C solution, a seed shaft, and an induction heater. The crucible includes a tubular portion and a bottom portion. The tubular portion includes an outer peripheral surface and an inner peripheral surface. The bottom portion is disposed at a lower end of the tubular portion. The bottom portion defines an inner bottom surface of the crucible. The outer peripheral surface includes a groove extending in a direction crossing the circumferential direction of the tubular portion.

Abstract: The provided by the disclosure is a SiC single crystal production method permitting suppression of temperature variation of a Si—C solution even in a case of long-time crystal growth. The SiC single crystal production method includes: a preparation step of preparing a production apparatus including a crucible, a seed shaft, and an internal lid; a formation step of heating the material in the crucible to form the Si—C solution; a growth step of bringing the seed crystal into contact with the Si—C solution to produce the Si—C single crystal on the seed crystal; an internal lid adjustment step of vertically moving one of the internal lid and the crucible relative to the other during the growth step to keep an amount of variation in vertical distance between the internal lid and the Si—C solution within a first reference range.