METHOD AND DEVICE FOR CONTROLLING GROWING MONOCRYSTALS FROM MELT Russian patent published in 1999 - IPC

FIELD: crystal growth. SUBSTANCE: invention relates to growing monocrystals from melt according to a special technique and can be employed in semiconductors production when manufacturing monocrystalline germanium ingots. Device consists of vertical rod on which growing monocrystal is fixed, pot with melt, power regulator, heater, melt level indicator (laser light source and photoelectric transducer), and programming level change commander. When specified- diameter monocrystal is pulled, melt level in pot is lowered, which is continuously controlled by melt level indicator. Change in diameter is constantly compensated by varying heat power of heat supplied to melt or varying crystal pulling velocity depending on intensity of signal associated with continuously measuring change in melt surface height. Measurement data are entered into power regulator connected with commander programmed in accordance with desired monocrystal diameter. Device also comprises flow chart: melt level indicator, growth velocity transducer, programming level change velocity commander, heater power (or pulling velocity) regulator. EFFECT: stabilized specified surface of growing crystal and enabled growth control. 2 cl