| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress the forming of a projection at the tail of a sapphire single crystal when growing the sapphire single crystal from a melt of aluminum oxide. Ž<P>SOLUTION: A method for producing the sapphire single crystal includes: a melting step to obtain the alumina melt by melting aluminum oxide in a crucible; a shoulder forming step to form a shoulder at the downward of a seed crystal by pulling the seed crystal being in contact with the alumina melt; a cylindrical part forming step to form a cylindrical part by pulling the sapphire single crystal from the melt; and a tail forming step to form the tail by supplying a mixed gas containing oxygen and an inert gas and having a predetermined oxygen concentration of 1.0 vol.% or more and 5.0 vol.% or less and by drawing the sapphire single crystal from the melt. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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