Synthesis of Lithium Niobate during Crystallization of Amorphous Li–Nb–O Film

Abstract

The structural and phase changes induced by heat treatment (HT) and brief lamp processing (LP) in 70- and 1500-nm-thick Li–Nb–O films similar in elemental composition to LiNbO₃, grown on the surface of unheated substrates (monocrystalline Si wafer and NaCl single crystal) by rf magnetron sputtering and ion-beam sputtering of a LiNbO₃ target have been studied by reflection high-energy electron diffraction and X‑ray diffraction. The as-grown films were extremely nanostructured and consisted of crystalline lithium oxides, niobium oxides, and LiNbO₃ as the product of reaction between them. We have demonstrated the conceptual feasibility of driving the synthesis of polycrystalline LiNbO₃ films to completion using HT or brief LP. In the case of LP, LiNbO₃ synthesis is three orders of magnitude faster than in the case of HT.