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.

A crucible having a tubular inner surface is prepared. A source material is arranged so as to make contact with the inner surface, and a seed crystal is arranged in the crucible so as to face the source material. A silicon carbide single crystal grows on the seed crystal by sublimation of the source material. The inner surface is formed of a first region surrounding the source material and a second region other than the first region. In the growing a silicon carbide single crystal, an amount of heat per unit area in the first region is smaller than an amount of heat per unit area in the second region.

A crucible having a tubular inner surface is prepared. A source material is arranged so as to make contact with the inner surface, and a seed crystal is arranged in the crucible so as to face the source material. A silicon carbide single crystal grows on the seed crystal by sublimation of the source material. The inner surface is formed of a first region surrounding the source material and a second region other than the first region. In the growing a silicon carbide single crystal, an amount of heat per unit area in the first region is smaller than an amount of heat per unit area in the second region.

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.

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.

An effusion cell includes a crucible for containing material to be evaporated or sublimated, a delivery tube configured to deliver evaporated or sublimated material originating from the crucible into a chamber, a supply tube extending from the crucible, the supply tube located and configured to trap condensate originating from the evaporated or sublimated material and to deliver the condensate back to the crucible, and at least one heating element located and configured to heat material in the crucible so as to cause evaporation or sublimation of the material and flow of the evaporated or sublimated material through the delivery tube and out from the effusion cell. The effusion cell is configured such that the crucible can be filled with the material to be evaporated or sublimated without removing the effusion cell from the process vacuum chamber. Semiconductor substrate processing systems may include such effusion cells.

Methods of passivating at least one facet of a multilayer waveguide structure can include: cleaning, in a first chamber of a multi-chamber ultra-high vacuum (UHV) system, a first facet of the multilayer waveguide structure; transferring the cleaned multilayer waveguide structure from the first chamber to a second chamber of the multi-chamber UHV system; forming, in the second chamber, a first single crystalline passivation layer on the first facet; transferring the multilayer waveguide structure from the second chamber to a third chamber of the multi-chamber UHV system; and forming, in the third chamber, a first dielectric coating on the first single crystalline passivation layer, in which the methods are performed in an UHV environment of the multi-chamber UHV system without removing the multilayer waveguide structure from the UHV environment.

Quality of a silicon carbide single crystal is improved. A crucible having first and second sides is prepared. A solid source material for growing silicon carbide with a sublimation method is arranged on the first side. A seed crystal made of silicon carbide is arranged on the second side. The crucible is arranged in a heat insulating container. The heat insulating container has an opening facing the second side. The crucible is heated such that the solid source material sublimes. A temperature on the second side is measured through the opening in the heat insulating container. The opening has a tapered inner surface narrowed toward the outside of the heat insulating container.

In one instance, the invention provides a bulk crystal of group III nitride having a thickness of more than 1 mm without cracking above the sides of a seed crystal. This bulk group III nitride crystal is expressed as Ga.sub.x1Al.sub.y1In.sub.1-x1-y1N (0≦x1≦1, 0≦x1+y1≦1) and the seed crystal is expressed as Ga.sub.x2Al.sub.y2In.sub.1-x2-y2N (0≦x2≦1, 0≦x2+y2≦1). The bulk crystal of group III nitride can be grown in supercritical ammonia or a melt of group III metal using at least one seed crystal having basal planes of c-orientation and sidewalls of m-orientation. By exposing only c-planes and m-planes in this instance, cracks originating from the sides of the seed crystal are avoided.

A group 13 element source, a flux comprising at least one of an alkali metal and an alkaline earth metal, and an additive being liquid at an ambient temperature are placed in a crystal growing vessel. The crystal growing vessel is heated and pressurized under a nitrogen atom-containing gas atmosphere to form a melt containing the group 13 element source, the flux and the additive. Evaporation of the additive is prevented until the flux is melted. The crystal of the nitride of the group 13 element is then grown in the melt.