Growth of piezoelectric single crystals by the pulling-down method

Abstract

Li/sub 2/B/sub 4/O/sub 7/ and LiNbO/sub 3/ single crystals were grown by the pulling-down (PD) method. By the method, single crystals can be easily obtained by solidifying the melt flowing out of a hole at the bottom of a crucible. The bubble free Li/sub 2/B/sub 4/O/sub 7/ crystals were obtained by using the PD method. Dislocation density was estimated to be about 1/spl sim/5/spl times/10/sup 4/ cm/sup -2/, which was somewhat more than that obtained by other methods. Crack free LiNbO/sub 3/ crystals have also successfully grown by the PD method. The as-grown crystals were transparent with slightly yellow in color. The crystals had stoichiometric composition because of feeding stoichiometric powder.