Abstract: A low defect (e.g., dislocation and micropipe) density silicon carbide (SiC) is provided as well as an apparatus and method for growing the same. The SiC crystal, grown using sublimation techniques, is preferably divided into two stages of growth. During the first stage of growth, the crystal grows in a normal direction while simultaneously expanding laterally. Although dislocations and other material defects may propagate within the axially grown material, defect propagation and generation in the laterally grown material are substantially reduced, if not altogether eliminated. After the crystal has expanded to the desired diameter, the second stage of growth begins in which lateral growth is suppressed and normal growth is enhanced. A substantially reduced defect density is maintained within the axially grown material that is based on the laterally grown first stage material.

Abstract: A low defect (e.g., dislocation and micropipe) density silicon carbide (SiC) is provided as well as an apparatus and method for growing the same. The SiC crystal, grown using sublimation techniques, is preferably divided into two stages of growth. During the first stage of growth, the crystal grows in a normal direction while simultaneously expanding laterally. Although dislocations and other material defects may propagate within the axially grown material, defect propagation and generation in the laterally grown material are substantially reduced, if not altogether eliminated. After the crystal has expanded to the desired diameter, the second stage of growth begins in which lateral growth is suppressed and normal growth is enhanced. A substantially reduced defect density is maintained within the axially grown material that is based on the laterally grown first stage material.

Abstract: A method and apparatus for axially growing single crystal silicon carbide is provided. Utilizing the system, silicon carbide can be grown with a dislocation density of less than 104 per square centimeter, a micropipe density of less than 10 per square centimeter, and a secondary phase inclusion density of less than 10 per cubic centimeter. As disclosed, a SiC source and a SiC seed crystal of the desired polytype are co-located within a crucible, the growth zone being defined by the substantially parallel surfaces of the source and the seed in combination with the sidewalls of the crucible. Prior to reaching the growth temperature, the crucible is evacuated and sealed, either directly or through the use of a secondary container housing the crucible. The crucible is comprised of tantalum or niobium that has been specially treated.

Abstract: A method and apparatus for axially growing single crystal silicon carbide is provided. Utilizing the system, silicon carbide can be grown with a dislocation density of less than 104 per square centimeter, a micropipe density of less than 10 per square centimeter, and a secondary phase inclusion density of less than 10 per cubic centimeter. As disclosed, a SiC source and a SiC seed crystal of the desired polytype are co-located within a crucible, the growth zone being defined by the substantially parallel surfaces of the source and the seed in combination with the sidewalls of the crucible. Prior to reaching the growth temperature, the crucible is evacuated and sealed, either directly or through the use of a secondary container housing the crucible. The crucible is comprised of tantalum or niobium that has been specially treated.

Abstract: A method and apparatus for axially growing single crystal silicon carbide is provided. Utilizing the system, silicon carbide can be grown with a dislocation density of less than 104 per square centimeter, a micropipe density of less than 10 per square centimeter, and a secondary phase inclusion density of less than 10 per cubic centimeter. As disclosed, a SiC source and a SiC seed crystal of the desired polytype are co-located within a crucible, the growth zone being defined by the substantially parallel surfaces of the source and the seed in combination with the sidewalls of the crucible. Prior to reaching the growth temperature, the crucible is evacuated and sealed, either directly or through the use of a secondary container housing the crucible. The crucible is comprised of tantalum or niobium that has been specially treated.

Abstract: A method and apparatus for axially growing single crystal silicon carbide is provided. Utilizing the system, silicon carbide can be grown with a dislocation density of less than 104 per square centimeter, a micropipe density of less than 10 per square centimeter, and a secondary phase inclusion density of less than 10 per cubic centimeter. As disclosed, a SiC source and a SiC seed crystal of the desired polytype are co-located within a crucible, the growth zone being defined by the substantially parallel surfaces of the source and the seed in combination with the sidewalls of the crucible. Prior to reaching the growth temperature, the crucible is evacuated and sealed, either directly or through the use of a secondary container housing the crucible. The crucible is comprised of tantalum or niobium that has been specially treated.

Abstract: A low defect (e.g., dislocation and micropipe) density silicon carbide (SiC) is provided as well as an apparatus and method for growing the same. The SiC crystal, grown using sublimation techniques, is preferably divided into two stages of growth. During the first stage of growth, the crystal grows in a normal direction while simultaneously expanding laterally. Although dislocations and other material defects may propagate within the axially grown material, defect propagation and generation in the laterally grown material are substantially reduced, if not altogether eliminated. After the crystal has expanded to the desired diameter, the second stage of growth begins in which lateral growth is suppressed and normal growth is enhanced. A substantially reduced defect density is maintained within the axially grown material that is based on the laterally grown first stage material.

Abstract: A low defect (e.g., dislocation and micropipe) density silicon carbide (SiC) is provided as well as an apparatus and method for growing the same. The SiC crystal, grown using sublimation techniques, is preferably divided into two stages of growth. During the first stage of growth, the crystal grows in a normal direction while simultaneously expanding laterally. Although dislocations and other material defects may propagate within the axially grown material, defect propagation and generation in the laterally grown material are substantially reduced, if not altogether eliminated. After the crystal has expanded to the desired diameter, the second stage of growth begins in which lateral growth is suppressed and normal growth is enhanced. A substantially reduced defect density is maintained within the axially grown material that is based on the laterally grown first stage material.

Abstract: A method and an apparatus for growing monocrystalline aluminum nitride are provided, the method and apparatus allowing high single crystal growth rates to be achieved. In one aspect, the seed crystal and the aluminum source are placed in a growth chamber such that the growth surface of the seed crystal is substantially parallel to the evaporating surface of the aluminum surface. In another aspect, the inner surfaces of the growth chamber are comprised of an alloy of tantalum and carbon. In another aspect, during crystal growth the aluminum source is kept at a temperature higher than the seed crystal in order to maintain an axial temperature gradient within the growth chamber. In another aspect, during crystal growth the nitrogen pressure within the growth chamber is at least equal to the pressure exerted by the aluminum-nitrogen vapor mixture.

Abstract: A low defect (e.g., dislocation and micropipe) density silicon carbide (SiC) is provided as well as an apparatus and method for growing the same. The SiC crystal, growing using sublimation techniques, is preferably divided into two stages of growth. During the first stage of growth, the crystal grows in a normal direction while simultaneously expanding laterally. Although dislocation and other material defects may propagate within the axially grown material, defect propagation and generation in the laterally grown material are substantially reduced, if not altogether eliminated. After the crystal has expanded to the desired diameter, the second stage of growth begins in which lateral growth is suppressed and normal growth is enhanced. A substantially reduced defect density is maintained within the axially grown material that is based on the laterally grown first stage material.

Abstract: A method and apparatus for axially growing single crystal silicon carbide is provided. Utilizing the system, silicon carbide can be grown with a dislocation density of less than 104 per square centimeter, a micropipe density of less than 10 per square centimeter, and a secondary phase inclusion density of less than 10 per cubic centimeter. As disclosed, a SiC source and a SiC seed crystal of the desired polytype are co-located within a crucible, the growth zone being defined by the substantially parallel surfaces of the source and the seed in combination with the sidewalls of the crucible. Prior to reaching the growth temperature, the crucible is evacuated and sealed, either directly or through the use of a secondary container housing the crucible. The crucible is comprised of tantalum or niobium that has been specially treated.

Abstract: A method and apparatus for axially growing single crystal silicon carbide is provided. Utilizing the system, silicon carbide can be grown with a dislocation density of less than 104 per square centimeter, a micropipe density of less than 10 per square centimeter, and a secondary phase inclusion density of less than 10 per cubic centimeter. As disclosed, a SiC source and a SiC seed crystal of the desired polytype are co-located within a crucible, the growth zone being defined by the substantially parallel surfaces of the source and the seed in combination with the sidewalls of the crucible. Prior to reaching the growth temperature, the crucible is evacuated and sealed, either directly or through the use of a secondary container housing the crucible. The crucible is comprised of tantalum or niobium that has been specially treated.

Abstract: A method and apparatus for axially growing single crystal silicon carbide is provided. Utilizing the system, silicon carbide can be grown with a dislocation density of less than 104 per square centimeter, a micropipe density of less than 10 per square centimeter, and a secondary phase inclusion density of less than 10 per cubic centimeter. As disclosed, a SiC source and a SiC seed crystal of the desired polytype are co-located within a crucible, the growth zone being defined by the substantially parallel surfaces of the source and the seed in combination with the sidewalls of the crucible. Prior to reaching the growth temperature, the crucible is evacuated and sealed, either directly or through the use of a secondary container housing the crucible. The crucible is comprised of tantalum or niobium that has been specially treated.

Abstract: A method and apparatus for axially growing single crystal silicon carbide is provided. Utilizing the system, silicon carbide can be grown with a dislocation density of less than 104 per square centimeter, a micropipe density of less than 10 per square centimeter, and a secondary phase inclusion density of less than 10 per cubic centimeter. As disclosed, a SiC source and a SiC seed crystal of the desired polytype are co-located within a crucible, the growth zone being defined by the substantially parallel surfaces of the source and the seed in combination with the sidewalls of the crucible. Prior to reaching the growth temperature, the crucible is evacuated and sealed, either directly or through the use of a secondary container housing the crucible. The crucible is comprised of tantalum or niobium that has been specially treated.

Abstract: A low dislocation density silicon carbide (SiC) is provided as well as an apparatus and method for growing the same. The SiC crystal, grown using sublimation techniques, is preferably divided into two stages of growth. During the first stage of growth, the crystal grows in a normal direction while simultaneously expanding laterally. Although dislocations and other material defects may propagate within the axially grown material, defect propagation and generation in the laterally grown material are substantially reduced, if not altogether eliminated. After the crystal has expanded to the desired diameter, the second stage of growth begins in which lateral growth is suppressed and normal growth is enhanced. A substantially reduced defect density is maintained within the axially grown material that is based on the laterally grown first stage material.

Abstract: A low dislocation density silicon carbide (SiC) is provided as well as an apparatus and method for growing the same. The SiC crystal, grown using sublimation techniques, is preferably divided into two stages of growth. During the first stage of growth, the crystal grows in a normal direction while simultaneously expanding laterally. Although dislocations and other material defects may propagate within the axially grown material, defect propagation and generation in the laterally grown material are substantially reduced, if not altogether eliminated. After the crystal has expanded to the desired diameter, the second stage of growth begins in which lateral growth is suppressed and normal growth is enhanced. A substantially reduced defect density is maintained within the axially grown material that is based on the laterally grown first stage material.

Abstract: A sublimation technique of growing silicon carbide single crystals, comprising a parallel arrangement, opposite each other, of the evaporating surface of a silicon carbide source (1) and the growing surface of at least one seed crystal (2) of a specified politype, to define a growth zone (4), and generation of a reduced pressure and an operating temperature field with an axial gradient in the direction from the seed crystal (2) towards the source (1), providing evaporation of silicon carbide of the source (1) and vapour-phase crystallization of silicon carbide on the growing surface of the seed crystal (2). The growth zone (4) is here sealed before the operating temperatures are reached therein, and the process is run with a solid solution of tantalum and silicon carbides in tantalum and their chemical compounds present in the growth zone (4). The material of the source (1) employed for implementing the sublimation technique of growing silicon carbide crystals is silison carbide ceramics.