A silicon carbide single crystal manufacturing apparatus includes a crucible constituted by a crucible body and a crucible lid; and a base that is placed on the underside of the crucible lid and holds a silicon carbide seed crystal, wherein the base has a structure in which a plurality of graphite plates having anisotropy of the thermal expansion coefficient are laminated and bonded, and when viewed in a plan view from the lamination direction, in the plurality of graphite plates, the maximum directional axes of the thermal expansion coefficient between adjacent graphite plates are orthogonal to each other or the maximum directional axes intersect within an angle range of ±15° from orthogonal.

The present disclosure provides a device for preparing a crystal and a method for growing a crystal. The device may include a growth chamber configured to execute a crystal growth; and a temperature control system configured to heat the growth chamber to cause that a radial temperature difference in the growth chamber does not exceed a first preset range of an average temperature in the growth chamber during the crystal growth. The method may include placing a seed crystal and a source material in a growth chamber to grow a crystal; and controlling a heating component based on information of a temperature sensing component, to cause that a radial temperature difference in the growth chamber does not exceed a first preset range of an average temperature in the growth chamber during a crystal growth.

A molecular beam epitaxial growth apparatus of the present disclosure includes a stage, a first molecular beam source irradiates a substrate surface with a first molecular beam, a second molecular beam source irradiates the substrate surface with a second molecular beam, a shutter shields the first molecular beam or the second molecular beam, and a control unit controls the shutter and relative positions of the stage with respect to the first molecular beam source and the second molecular beam source. The radiation direction of the first molecular beam emitted from the first molecular beam source and the radiation direction of the second molecular beam emitted from the second molecular beam source are vertical to the substrate surface. Under the control of the control unit, the second molecular beam is shielded while the first molecular beam is radiated on the substrate surface, and the first molecular beam is shielded while the second molecular beam is radiated on the substrate surface.

There is a method for forming a semiconductor nanostructure on a substrate. The method includes placing a substrate and a semiconductor material in a pulsed laser deposition chamber; selecting parameters including a fluence of a laser beam, a pressure P inside the chamber, a temperature T of the substrate, a distance d between the semiconductor material and the substrate, and a gas molecule diameter a.sub.0 of a gas to be placed inside the chamber so that conditions for a Stranski-Krastanov nucleation are created; and applying the laser beam with the selected fluence to the semiconductor material to form a plume of the semiconductor material. The selected parameters determine the formation, from the plume, of (1) a nanolayer that covers the substrate, (2) a polycrystalline wetting layer over the nanolayer, and (3) a single-crystal nanofeature over the polycrystalline wetting layer, and the single-crystal nanofeature is grown free of any catalyst or seeding layer.

The method of preparing a silicon carbide ingot includes: disposing a raw material and a silicon carbide seed crystal to be separated in a reactor having an internal space; adjusting a temperature, a pressure, and an atmosphere of the internal space for sublimating the raw material and growing the silicon carbide ingot on the silicon carbide seed crystal; and cooling the reactor and retrieving the silicon carbide ingot, wherein the adjusting proceeds in a first inert gas atmosphere having a flow quantity of 100 sccm to 300 sccm, the cooling proceeds in a second inert gas atmosphere having a flow quantity of 1 sccm to 250 sccm, and the reactor has a thermal conductivity of 120 W/mK or less.

A silicon carbide ingot manufacturing method and a silicon carbide ingot manufacturing system are provided. The silicon carbide ingot manufacturing method and the silicon carbide ingot manufacturing system may change a temperature gradient depending on the growth of an ingot by implementing a guide which has a tilted angle to an external direction from the interior of a reactor, in an operation to grow an ingot during a silicon carbide ingot manufacturing process.

A silicon carbide ingot is provided, which includes a seed end, and a dome end opposite to the seed end. In the silicon carbide ingot, a ratio of the vanadium concentration to the nitrogen concentration at the seed end is in a range of 5:1 to 11:1, and a ratio of the vanadium concentration to the nitrogen concentration at the dome end is in a range of 2:1 to 11:1.

A method for manufacturing a SiC single crystal having a growth container surrounded by a heat-insulating material, a seed crystal substrate disposed inside a top at a center of the container, a silicon carbide raw material disposed at a bottom of the container to sublimate and grow a SiC crystal to allow a center of the hole to deviate from a center position of the seed substrate to a position on a periphery side, a SiC substrate having a main surface tilted from a {0001} plane wherein a basal plane is used and grown with the seed substrate so that a direction of a component of a normal vector of the basal plane of the seed substrate parallel to the main surface and an eccentric direction of the hole are opposite directions in a cross-sectional view including the center of the seed substrate and the center of the hole.

A silicon carbide ingot producing method is provided. The method produces a silicon carbide ingot in which an internal space of a reactor is depressurized and heated to create a predetermined difference in temperature between upper and lower portions of the internal space. The method produces a silicon carbide ingot in which a plane of a seed crystal corresponding to the rear surface of the silicon carbide ingot is lost minimally. Additionally, the method produces a silicon carbide ingot with few defects and good crystal quality.

The embodiments of the present disclosure disclose a method and an apparatus for crystal growth. The method for crystal growth may include: placing a seed crystal and a target source material in a growth chamber of an apparatus for crystal growth; executing a growth of a crystal based on the seed crystal and the target source material according to physical vapor transport; determining whether a preset condition is satisfied during the crystal growth process; and in response to determining that the preset condition is satisfied, replacing a sublimated target source material with a candidate source material. In the present disclosure, by replacing the sublimated target source material with the candidate source material, a crystal with large-size and high-quality can be grown.