Large Diameter Silicon Carbide Single Crystals and Apparatus and Method of Manufacture Thereof

A PVT growth apparatus for PVT growing an SiC single crystal comprising:

• a growth chamber;
• a growth crucible positioned in the growth chamber, the growth crucible configured to be charged with a SiC source material at a bottom of the growth crucible and a single crystal SiC seed at a top or lid of the growth crucible with the SiC source material and the single crystal SiC seed in spaced relation;
• thermal insulation surrounding the growth crucible inside of the growth chamber, the thermal insulation including a side insulation piece between a side of the growth crucible and a side of the growth chamber, a bottom insulation piece between the bottom of the growth crucible and a bottom of the growth chamber, a top insulation piece between the top of the growth crucible and a top of the growth chamber, and an insulation insert positioned in an opening in the top insulation piece, wherein the insulation insert has a thickness between 20 mm and 50 mm and a largest dimension between 90% and 120% of a largest dimension of the single crystal SiC seed;
• and
• a heater positioned between the bottom of the growth crucible and the bottom insulation piece, wherein a geometry of the insulation insert is tuned to control heat flux in the SiC single crystal that grows on the single crystal SiC seed in use of the PVT growth apparatus.