Effects of excess amount of K and Na on properties of (K _0.48Na _0.52)NbO ₃ thin films

The excess amounts of K and Na in precursor solutions are very important for the phase structure and performance of (K _0.48Na _0.52)NbO ₃ (KNN) thin films because of their volatilization loss. However, there are no identical opinions have been reported that could describe which element is easily volatile. In this paper, different excessive amounts of K and Na are added simultaneously in precursor solutions, the lead-free KNN thin films are prepared by metallorganic compound decomposition (MOD) method. Through comparison of phase structures, dielectric properties, J-E characteristic and ferroelectric P-E hysteresis loops, the effects of chemical componential fluctuation of K and Na on properties of KNN thin films are discussed systematically.