Conclusions

Abstract

In this study, Synthesis of a homogeneous KN film was difficult because of the evaporation of K₂O during the growth process. The KN film should be deposited at RT to avoid the evaporation of K₂O since the K-deficient K_2.88Nb₅O₁₅ secondary phase was formed in the KN film grown at the very low temperature of 100 °C. Moreover, the annealing of KN films should be conducted at 800 °C, because when the annealing temperature is greater than that, a K-deficient K_2.88Nb₅O₁₅ secondary phase is also formed. Moreover, a transient KNb₃O₈ secondary phase was formed when the annealing temperature was less than 800 °C.