PURPOSE: To suppress turbulent convective flow and to grow a single crystal having a homogeneous distribution of impurities by pulling up a molten material melted by heating near the apex of a vessel from a free surface lowered by a pressure means via a member having an opening common therewith.
CONSTITUTION: A pressure tube 20 made of silica forming a chamber 21 is supported via a silica cap 14 at the center in a silica crucible 12 housing the molten silicon 16 of the apparatus 10 for pulling up the crystal and is so disposed that its opening end 22 exists near the bottom of the crucible 12. An inert gas is supplied from the port 24 of a cap 14 into an annular space 26 and the molten silicon 16 is heated by a radiation electric heater 30 disposed there. On the other hand, the inert gas is introduced from an inlet duct 50 and is discharged from an outlet duct and is controlled to a desired pressure by means of a pressure regulator 54 and a flow rate regulating valve 56 to lower the free surface 60 of the molten silicon 16. Next, the molten silicon is heated by the radiation electric heater 30 and is cooled by a cooler 32 to make the temp. gradient uniform and to stop convection and thereafter, a shaft 44 and a disk 46 are rotationally lowered and are brought into contact with the free surface 60. The molten silicon is then gradually pulled up to allow the single crystal to grow.
JIEIMUZU MAATEIN ROBAATOSON
PIITAA KORIN RABUGUROOBU
