PRODUCTION OF COMPOUND SEMICONDUCTOR SINGLE CRYSTAL

摘要

PURPOSE:To maintain the cooling rate of a solid-liquid interface at a constant level in the growth of a single crystal by vertical coagulation process and to stabilize the quality of the single crystal, by lifting a heater at the outer circumference of a growth vessel while fixing a crucible containing molten liquid of semiconductor and a growth vessel. CONSTITUTION:A crucible 15 is coaxially placed in a vertically disposed growth vessel 13. A seed crystal 49 is inserted into a tubular part 15a attached to the bottom part of the crucible and set to a prescribed position. A polycrystalline raw material 51 for compound semiconductor is filled in the crucible 15. After filling a group V element 53 in a lower vessel 17, the crucible 15 and a pressure vessel 11 are evacuated, filled with an inert gas to a prescribed pressure and covered with a lid 21. The raw material 51 is melted with a main heater 31 and the crystal 49 is made to contact with the molten liquid to effect the seeding. The vapor pressure of the element 53 is controlled with a subsidiary heater 37. Thereafter, a heater-supporting shaft 43 is slowly raised to life only the heater 31 and effect the growth of a single crystal from the seeded part upward.