| 摘要 |
PURPOSE:To prevent the sticking of an evaporated material to a quartz tube near a hole and monitor the interior of a growing furnace thoroughly, by passing an atmospheric gas through a larger clearance between a furnace for growing a single crystal and a quartz tube provided around the furnace at the position of the hole of the furnace than that at other positions. CONSTITUTION:A transparent quartz tube 1 is provided around a furnace for growing a single crystal having a noble metallic crucible 3, and a high-frequency heating coil 12 is provided around the quartz tube 1 to grow a single crystal of a highly volatile substance, e.g. tellurium dioxide. In the process, a clearance 13 between the outer peripheral surface of the furnace and the inner peripheral surface of the quartz tube 1 at the position of a hole 8 at the side of the furnace is set larger than at other positions. An atmospheric gas fed from the upper inlet 10 in the growing is passed through the clearance 13 between the outer peripheral surface of the furnace and the inner peripheral surface of the quartz tube 1 while containing the evaporated substance and then discharged from the bottom outlet 11 and partially introduced from the hole 8 into the interior of the furnace. The large clearance 13 near the hole 8 permits the increase in the flow rate of the atmospheric gas flowing into the hole 8, and the sticking of the fine evaporated particles to the quartz tube 1 is prevented. Thus, the interior of the furnace for growing the single crystal can be observed in good conditions. |
