APPARATUS FOR PRODUCING SINGLE CRYSTAL OF HIGH DISSOCIATION PRESSURE COMPOUND

摘要

PURPOSE:To improve the yield of a single crystal of a high dissociation pressure compd. by forming a surface part for forming a sealing vessel for a gaseous component to be interposed in the visual field in a sealing vessel for gaseous volatile component in such a manner that said part exists at a specific angle with the optical axis of a peep window. CONSTITUTION:A crucible 8 is supported rotatably by a crucible rotating and lifting shaft 9 and a heater is disposed to enclose the crucible 8 in a furnace wall 1. The transparent cup-shaped sealing vessel 3 for the gaseous volatile component is disposed around a rotatable pulling up shaft 5. The front end part of the downward facing vessel is formed to the shape to fit into the inside of the crucible 8 so that this front end part is held dipped in a liquid sealant 7 covering a raw material melt during the operation. The top of the vessel 3 is interposed with the liquid sealant 7 between said part and the shaft 5 to maintain evaporated; for example, gaseous As, in a sealed state and produces the single crystal by a CZ method. The peep window 2 is provided through the furnace wall 1. The surface 3' forming a part of the sealing vessel 3 for the gaseous volatile component is so formed as to exist nearly perpendicularly to the optical axis 12 in the visual field of the window 2 or at the angle within 5 deg. therewith. The sealing vessel constituted in the above-mentioned manner is used.