| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a single crystal pulling apparatus capable of detecting in a short time from occurrence, melting of the outer surface of a crucible or overflow of raw material melt from the crucible. <P>SOLUTION: This single crystal pulling apparatus 1 includes: an upper heater 30 provided so as to enclose a crucible 20 for holding alumina melt 300, for heating the crucible 20 from a wall part 22; a facing part provided below the crucible 20, positioned inside an image formed by projecting the crucible 20 in the vertical direction, and facing to a bottom part 21; and a peripheral part projected to the outside of the image formed by projecting the crucible 20 in the vertical direction, and also includes: a lower heater 35 for heating the crucible 20 from the bottom part 21; a pulling rod 40 for pulling a sapphire ingot 200 from the alumina melt 300; a measuring part 96 for measuring a current flowing in the lower heater 35 or a voltage; and a determination part 97 for determining existence of a falling object onto the lower heater 35 from the crucible 20 based on the current or the voltage measured by the measuring part 96. <P>COPYRIGHT: (C)2013,JPO&INPIT |
