SOLID-PHASE EPITAXIAL-GROWTH OF LITHIUM TANTALATE THIN-FILMS DEPOSITED BY SPRAY-METALORGANIC CHEMICAL-VAPOR-DEPOSITION

We demonstrate the solid-phase epitaxial crystallization of thin films of lithium tantalate deposited on lithium niobate and sapphire substr ates. An organometallic compound, formed by reaction of lithium dipiva loylmethanate and tantalum(V) ethoxide, is used as a single-source pre cursor for the deposition of amorphous thin films of lithium tantalate using a spray-metalorganic chemical vapor deposition process. Anneali ng of the amorphous films results in their epitaxial alignment with re spect to the underlying LiNbO3 or Al2O3 substrates. X-ray diffraction, ion channeling, and scanning electron microscopy are used to evaluate and compare the crystalline quality of the films produced by this sol id-phase epitaxial process to films that are crystalline as deposited.