METHOD OF GROWING PIEZOELECTRIC LANTHANIDE GALLIUM CRYSTALS

摘要

A method for producing piezoelectric lanthanide gallium crystals includes pulling a crystal through a forming mould dipped into a crucible containing a melt, which controls a heat and mass transfer, as the crystal is grown. While a lanthanide gallium single crystal is growing, a charge of mixed oxides, having a composition of the melt may be continuously added to the melt such that the quantity of melt is maintained substantially stable. Crystals produced by this method exhibit less variability in piezoelectric properties. The growth direction of the crystal is aligned along an axis perpendicular to such a crystallographic plane of lanthanide gallium crystal that an improved temperature stability, lowered power flow angle, and reduced diffraction would be present in surface acoustic wave (SAW) devices made in this crystallographic plane. Such crystals are more suitable for the mass-production slicing wafers, for example over 2 inches in diameter, for SAW devices.