MANUFACTURING METHOD OF SAPPHIRE SINGLE CRYSTAL

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method of a sapphire single crystal that grows a high-quality sapphire single crystal easily and at a low cost by a unidirectional solidification method.SOLUTION: A crucible 1 is made of W, Mo or a W-Mo alloy and has an inclined part or a round part formed in a boundary 4 between an inner bottom surface 3 and an inner peripheral surface 2. A seed crystal 6a is housed in the crucible 1 and a raw material 9 is loaded on the seed crystal 6a to grow a sapphire single crystal by a unidirectional solidification method. A spacer 12 composed of at least one flat plate and having an area of an undersurface 14 of 70-100% of that of a flat part 5 of the inner bottom surface 3 of the crucible 1 is arranged between the flat part 5 and an undersurface 8a of the seed crystal 6a so that the undersurface 8a of the seed crystal 6a may not touch the boundary 4 and that the spacer 12 may support the seed crystal 6a.