| 摘要 |
PURPOSE:To prepare a single crystal of good quality with a variation in diameter controlled in a minute range in the preparation of the single crystal of a compound of an element selected from Groups III-V in which the diameter of the single crystal cannot be easily controlled, by controlling the temperature based on the time differential of deviation in the weight of the single crystal. CONSTITUTION:A crystal 4 is pulled up from a liquid capsule 2 of a GaP melt 1 contained in a crucible 6 of a high-pressure vessel 9 with a seed crystal 3 by a pulling up shaft 5. The weight of the crystal 4 is sensed by a sensor 10, and the sensed values and an output from a standard weight signal generator 11 synchronized with the pulling are input to a deviation sensing apparatus 12 to calculate the deviation in weight. The deviation output is differentiated in the first differentiating apparatus 13 with respect to time to give the first differential, which is then corrected by a standard diameter signal generator 14 and secondarily differetiated by the second differentiating apparatus 15. The first and the second differential signals are input to a phase compensating apparatus 16 and then heating apparatus controlling circuit 17 to control the heating apparatus 18 of a heater 7 and adjust the temperature of the melt 1. |
