METHOD OF GROWING MONOCRYSTALS OF LANTHANUM GALLIC SILICATE Russian patent published in 1999 - IPC

FIELD: growing monocrystals of lanthanum gallic silicate used for manufacture of device of volume and surface acoustic waves. SUBSTANCE: langasite charge is synthesized by solid-phase synthesis and is placed in iridic crucible mounted in thermal unit of growth plant CRYSTAL-3M. Revolving seed crystal oriented in way of 54 deg at axis "Y" os brought in contact with surface of melt. Growth is performed in protective atmosphere at frequency of rotation of crystal holder of 1 to 7 rev/min; axial gradient ranges from 1 to 15 C/cm. After- growth annealing of crystal is performed at rate of cooling of 15 C/h for 40 hours and at rate 25 C/h for 24 hours. Method ensures growing of high-quality crystals which may be used for manufacture of crystal elements of surface acoustic wave filters. Sawing of grown bull-langasite is effected perpendicularly relative to axis of growth, thus reducing cost of crystal disks. EFFECT: enhanced efficiency. 2 dwg, 1 tbl