Patent ID: 7524375
Filing Date: 2009-04-28
Classification: C30B,Y10S,Y10T

Abstract:
1. An apparatus for crystal growth comprising, a) a vessel configured to hold seed crystal therein below with precursor charge or melt thereon, b) means for installing said seed crystal and said charge in said vessel, with said crystal below said charge for bottom-seeded crystal growth, c) a small inner elongated electrode mounted within said vessel at or near the vertical axis thereof, which electrode extends into said charge or melt but does not contact said crystal, d) an outer electrode of graphite which extends substantially around said inner electrode, and proximate the inner walls of said vessel, e) heater means to heat said charge to a molten state to form a melt, f) means for applying a voltage across said electrodes to generate a radial electric current in said melt, g) an induction coil mounted around the vessel and h) means to stir said melt non mechanically by applying voltage to said coil to impose magnetic field lines in said melt such that the flow of said radial electric current crosses said magnetic field lines to impart a stirring force to said melt for greater uniformity in melt and crystal.