| 摘要 |
PURPOSE:To suppress turbulent convection of raw material melt and to grow single crystal of low dislocation density in high yield, by carrying out crystal growth in such a way that the separated position of a first and a second heaters is not made higher than the liquid level of raw material melt. CONSTITUTION:Raw material melt 3 and a liquid sealing agent 4 in a crucible 16 are kept in a melt state by the heat of heaters 1 and 2. In the operation, a separated position Z of the first heater 1 and the second heater 2 is made not lower than melt liquid level W, namely, Z >= W. Since the raw material melt is heated by one heater, no turbulent convection will occur and stable steady convection exists. When seed is immersed, W = Z is kept. When crystal is grown while maintaining height of lower axis constant, the melt liquid level W naturally lowers and correlation W < Z is attained. On the contrary, it is also possible to raise the lower axis and to make the position of solid-liquid interface invariable and the correlation is always W <= Z in this case. High- quality single crystal with low dislocation density can be obtained and single crystal can be grown in high yield.
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