PRODUCTION OF GAAS SINGLE CRYSTAL

摘要

PURPOSE:To obtain the titled GaAs single crystal having high uniformity and suitably used in a substrate for a high-speed and highly integrated circuit by synthesizing the melt of raw materials directly from Ga and As which are charged in a specified ratio of the numbers of atoms under a liq. capsule agent. CONSTITUTION:High-purity Ga and high-purity As are charged into a crucible 4 so that the ratio of the numbers of the atoms Ga/As is regulated to 0.9-0.925 and a liq. capsule agent 5 (e.g., boron oxide) is placed thereon. Then the inside of a high-pressure vessel 1 is evacuated by a vacuum pump and an inert gas (e.g., nitrogen and argon) is introduced at about 15-20atm. The materials are heated by a heater 2 and Ga and As are combined under the liq. capsule agent 5. The compd. is further heated to form the melt 6 of GaAs and a seed crytal 7 provided to a pulling shaft is brought into contact with the melt 6 and then pulled up to obtain the desired GaAs single crystal 8.