A crystal growth apparatus includes: a chamber including a gas inlet, a gas outlet, a welded portion, and a water-cooling portion configured to water-cool a portion at least including the welded portion; an exhaust pump connected to the gas outlet; a dew point instrument disposed between the gas outlet and the exhaust pump, the dew point instrument being configured to measure a dew point of gas passing through the gas outlet.

A crystal growth apparatus includes: a chamber including a gas inlet, a gas outlet, a welded portion, and a water-cooling portion configured to water-cool a portion at least including the welded portion; an exhaust pump connected to the gas outlet; a dew point instrument disposed between the gas outlet and the exhaust pump, the dew point instrument being configured to measure a dew point of gas passing through the gas outlet.

In various embodiments, controlled heating and/or cooling conditions are utilized during the fabrication of aluminum nitride single crystals and aluminum nitride bulk polycrystalline ceramics. Thermal treatments may also be utilized to control properties of aluminum nitride crystals after fabrication.

The purpose of the present is to provide a modified AlN source for suppressing downfall defects. This manufacturing method of a modified aluminum nitride source involves a heat treatment step for heat treating an aluminum nitride source and generating an aluminum nitride sintered body.

Provided is a method of enhancing silicon carbide monocrystalline growth yield, including the steps of: (A) filling a bottom of a graphite crucible with a silicon carbide raw material selected; (B) performing configuration modification on a graphite seed crystal platform; (C) fastening a silicon carbide seed crystal to the modified graphite seed crystal platform with a graphite clamping accessory; (D) placing the graphite crucible containing the silicon carbide raw material and the silicon carbide seed crystal in an inductive high-temperature furnace; (E) performing silicon carbide crystal growth process by physical vapor transport; and (F) obtaining silicon carbide monocrystalline crystals. The geometric configuration of the surface of the graphite seed crystal platform is modified to eradicate development of peripheral grain boundary.

The present disclosure provides a method for growing a seed crystal, including: obtaining a plurality of orthohexagonal seed crystals in a hexagonal crystal system by performing a first cutting on a plurality of seed crystals in the hexagonal crystal system to be expanded, respectively; splicing the plurality of orthohexagonal seed crystals in the hexagonal crystal system; obtaining a seed crystal in the hexagonal crystal system to be grown by performing a second cutting on the plurality of spliced orthohexagonal seed crystals in the hexagonal crystal system; obtaining an intermediate seed crystal in the hexagonal crystal system by performing a gap growth on the seed crystal in the hexagonal crystal system to be grown under a first setting condition; and obtaining a target seed crystal in the hexagonal crystal system by performing an epitaxial growth on the intermediate seed crystal in the hexagonal crystal system under a second setting condition.

The present disclosure provides a method for growing a seed crystal, including: obtaining a plurality of orthohexagonal seed crystals in a hexagonal crystal system by performing a first cutting on a plurality of seed crystals in the hexagonal crystal system to be expanded, respectively; splicing the plurality of orthohexagonal seed crystals in the hexagonal crystal system; obtaining a seed crystal in the hexagonal crystal system to be grown by performing a second cutting on the plurality of spliced orthohexagonal seed crystals in the hexagonal crystal system; obtaining an intermediate seed crystal in the hexagonal crystal system by performing a gap growth on the seed crystal in the hexagonal crystal system to be grown under a first setting condition; and obtaining a target seed crystal in the hexagonal crystal system by performing an epitaxial growth on the intermediate seed crystal in the hexagonal crystal system under a second setting condition.

A bulk SiC single crystal is produced by placing an SiC seed crystal in a crystal growth region of a growth crucible, and introducing SiC source material into an SiC reservoir region, and the bulk SiC single crystal is grown on from an SiC growth gas phase by deposition. The growth crucible is surrounded by an insulation that extends rotationally symmetrically and axially towards the central middle longitudinal axis. The insulation has mutually concentric insulation cylinder components and the insulation is notionally divided into insulation ring segments that are in turn notionally divided into volume elements. The insulation cylinder components are selected and positioned relative to one another such that every volume element of the insulation ring segment in question has a volume element density varying by not more than 10% from an average insulation ring segment density of the insulation ring segment in question.

A bulk SiC single crystal is produced by placing an SiC seed crystal in a crystal growth region of a growth crucible, and introducing SiC source material into an SiC reservoir region, and the bulk SiC single crystal is grown on from an SiC growth gas phase by deposition. The growth crucible is surrounded by an insulation that extends rotationally symmetrically and axially towards the central middle longitudinal axis. The insulation has mutually concentric insulation cylinder components and the insulation is notionally divided into insulation ring segments that are in turn notionally divided into volume elements. The insulation cylinder components are selected and positioned relative to one another such that every volume element of the insulation ring segment in question has a volume element density varying by not more than 10% from an average insulation ring segment density of the insulation ring segment in question.

A shielding member placed between a SiC source loading portion and a crystal installation portion in an apparatus for single crystal growth, including a crystal growth container including the loading portion which accommodates a SiC source in an inner bottom portion; a crystal installation portion facing the loading portion, and a heating unit configured to heat the crystal growth container. The device grows a single crystal of the SiC source on a crystal installed on the crystal installation portion by sublimating the SiC source from the loading portion. The shielding member includes a plurality of shielding plates, wherein each area of the plurality of shielding plates is 40% or less of a base area of the crystal growth container. When the SiC source loading portion is filled with a SiC source, a shielding ratio provided by a projection surface of the plurality of shielding plates is 0.5 or more.