| 摘要 |
PROBLEM TO BE SOLVED: To provide a high quality polycrystal silicon at good productivity and high yield by accurately detecting the timing for melting whole raw material in a melting crucible in every time, controlling the molten silicon temperature in the melting crucible before tapping off in good reappearance for short time and tapping off. SOLUTION: A casting apparatus for polycrystal silicon, is provided with the melting crucible 1 for forming the molten silicon by heating and melting the raw material silicon held in the inner part, heating means 5, 6 for heating and melting the raw material silicon, a first thermocouple 10 for detecting the raw material temperature for silicon, held in the inner part of the melting crucible 1, a second thermocouple 11 for detecting the outer surface temperature of the melting crucible 1 and a molten liquid temperature control means 12 for controlling the heating means 5, 6 so that the raw material temperature measured with the temperature detecting means becomes a prescribed target value when becoming a second prescribed value or higher after a changing ratio with timeΔT/Δt of the outer surface temperature measured with the second thermocouple 11 is passed through the state of less than a first prescribed value. COPYRIGHT: (C)2006,JPO&NCIPI
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