Characterization of LiNbO3 crystals by line-focus-beam acoustic microscopy

Abstract

Line-focus-beam (LFB) acoustic microscopy is applied to quantitative characterization of piezoelectric LiNbO3 crystals to demonstrate the usefulness of this new analytical technique. Experimental relations between chemical composition ratios of Li/Nb and leaky surface acoustic wave (LSAW) velocities for 128°YX LiNbO3 wafers are determined. LSAW velocity measurements are carried out for commercial wafers obtained from a series of crystal growths. Small changes of 0.092% are detected due to the compositional variation. It is estimated that the ‘‘effective’’ congruent composition in the production line is 48.440 Li2O mol% with the density of 4647.4 kg/m3.