Method of manufacturing potassium niobate single crystal thin film, surface acoustic wave element, frequency filter, frequency oscillator, electronic circuit, and electronic apparatus

摘要

A method of manufacturing KNbO₃ single crystal thin film having single-phase high quality and excellent morphology on each of single crystal substrates. A surface acoustic wave element, frequency filter, frequency oscillator, electronics circuit, and electronic device employ the thin film manufactured by the method, and have high k², and are wideband, reduced in size and economical in power consumption. A plasma plume containing K, Nb, and O in the range 0.5≦x≦x_E is supplied to a substrate, where x is a mole ratio of niobium (Nb) to potassium (K) in K_xNb_1-xO_y, and x_E is a mole composition ratio at the eutectic point for KNbO₃ and 3K₂O.Nb₂O₅ under a predetermined oxygen partial pressure. Maintaining the temperature T_s of the substrate in the range T_E≦T_s≦T_m where T_E represents the temperature at the eutectic point and T_m represents a complete melting temperature, the KNbO3 single crystal is precipitated from the K_xNb_1-xO_y deposited on the substrate.